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'AES' -- Possible downref: Non-RFC (?) normative reference: ref. 'DSS' ** Downref: Normative reference to an Informational RFC: RFC 2104 ** Obsolete normative reference: RFC 2898 (Obsoleted by RFC 8018) ** Downref: Normative reference to an Informational RFC: RFC 3394 ** Downref: Normative reference to an Informational RFC: RFC 6090 ** Obsolete normative reference: RFC 7159 (Obsoleted by RFC 8259) -- Possible downref: Non-RFC (?) normative reference: ref. 'SEC1' -- Possible downref: Non-RFC (?) normative reference: ref. 'SHS' -- Possible downref: Non-RFC (?) normative reference: ref. 'USASCII' == Outdated reference: A later version (-18) exists of draft-ietf-precis-saslprepbis-07 == Outdated reference: A later version (-05) exists of draft-mcgrew-aead-aes-cbc-hmac-sha2-04 -- Obsolete informational reference (is this intentional?): RFC 3447 (Obsoleted by RFC 8017) -- Obsolete informational reference (is this intentional?): RFC 5226 (Obsoleted by RFC 8126) Summary: 5 errors (**), 0 flaws (~~), 4 warnings (==), 29 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 JOSE Working Group M. Jones 3 Internet-Draft Microsoft 4 Intended status: Standards Track April 30, 2014 5 Expires: November 1, 2014 7 JSON Web Algorithms (JWA) 8 draft-ietf-jose-json-web-algorithms-26 10 Abstract 12 The JSON Web Algorithms (JWA) specification registers cryptographic 13 algorithms and identifiers to be used with the JSON Web Signature 14 (JWS), JSON Web Encryption (JWE), and JSON Web Key (JWK) 15 specifications. It defines several IANA registries for these 16 identifiers. 18 Status of this Memo 20 This Internet-Draft is submitted in full conformance with the 21 provisions of BCP 78 and BCP 79. 23 Internet-Drafts are working documents of the Internet Engineering 24 Task Force (IETF). Note that other groups may also distribute 25 working documents as Internet-Drafts. The list of current Internet- 26 Drafts is at http://datatracker.ietf.org/drafts/current/. 28 Internet-Drafts are draft documents valid for a maximum of six months 29 and may be updated, replaced, or obsoleted by other documents at any 30 time. It is inappropriate to use Internet-Drafts as reference 31 material or to cite them other than as "work in progress." 33 This Internet-Draft will expire on November 1, 2014. 35 Copyright Notice 37 Copyright (c) 2014 IETF Trust and the persons identified as the 38 document authors. All rights reserved. 40 This document is subject to BCP 78 and the IETF Trust's Legal 41 Provisions Relating to IETF Documents 42 (http://trustee.ietf.org/license-info) in effect on the date of 43 publication of this document. Please review these documents 44 carefully, as they describe your rights and restrictions with respect 45 to this document. Code Components extracted from this document must 46 include Simplified BSD License text as described in Section 4.e of 47 the Trust Legal Provisions and are provided without warranty as 48 described in the Simplified BSD License. 50 Table of Contents 52 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 5 53 1.1. Notational Conventions . . . . . . . . . . . . . . . . . . 5 54 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5 55 3. Cryptographic Algorithms for Digital Signatures and MACs . . . 6 56 3.1. "alg" (Algorithm) Header Parameter Values for JWS . . . . 6 57 3.2. HMAC with SHA-2 Functions . . . . . . . . . . . . . . . . 7 58 3.3. Digital Signature with RSASSA-PKCS1-V1_5 . . . . . . . . . 8 59 3.4. Digital Signature with ECDSA . . . . . . . . . . . . . . . 9 60 3.5. Digital Signature with RSASSA-PSS . . . . . . . . . . . . 10 61 3.6. Using the Algorithm "none" . . . . . . . . . . . . . . . . 11 62 4. Cryptographic Algorithms for Key Management . . . . . . . . . 12 63 4.1. "alg" (Algorithm) Header Parameter Values for JWE . . . . 12 64 4.2. Key Encryption with RSAES-PKCS1-V1_5 . . . . . . . . . . . 14 65 4.3. Key Encryption with RSAES OAEP . . . . . . . . . . . . . . 14 66 4.4. Key Wrapping with AES Key Wrap . . . . . . . . . . . . . . 15 67 4.5. Direct Encryption with a Shared Symmetric Key . . . . . . 15 68 4.6. Key Agreement with Elliptic Curve Diffie-Hellman 69 Ephemeral Static (ECDH-ES) . . . . . . . . . . . . . . . . 15 70 4.6.1. Header Parameters Used for ECDH Key Agreement . . . . 16 71 4.6.1.1. "epk" (Ephemeral Public Key) Header Parameter . . 16 72 4.6.1.2. "apu" (Agreement PartyUInfo) Header Parameter . . 17 73 4.6.1.3. "apv" (Agreement PartyVInfo) Header Parameter . . 17 74 4.6.2. Key Derivation for ECDH Key Agreement . . . . . . . . 17 75 4.7. Key Encryption with AES GCM . . . . . . . . . . . . . . . 19 76 4.7.1. Header Parameters Used for AES GCM Key Encryption . . 19 77 4.7.1.1. "iv" (Initialization Vector) Header Parameter . . 19 78 4.7.1.2. "tag" (Authentication Tag) Header Parameter . . . 20 79 4.8. Key Encryption with PBES2 . . . . . . . . . . . . . . . . 20 80 4.8.1. Header Parameters Used for PBES2 Key Encryption . . . 21 81 4.8.1.1. "p2s" (PBES2 salt input) Parameter . . . . . . . . 21 82 4.8.1.2. "p2c" (PBES2 count) Parameter . . . . . . . . . . 21 83 5. Cryptographic Algorithms for Content Encryption . . . . . . . 21 84 5.1. "enc" (Encryption Algorithm) Header Parameter Values 85 for JWE . . . . . . . . . . . . . . . . . . . . . . . . . 21 86 5.2. AES_CBC_HMAC_SHA2 Algorithms . . . . . . . . . . . . . . . 22 87 5.2.1. Conventions Used in Defining AES_CBC_HMAC_SHA2 . . . . 23 88 5.2.2. Generic AES_CBC_HMAC_SHA2 Algorithm . . . . . . . . . 23 89 5.2.2.1. AES_CBC_HMAC_SHA2 Encryption . . . . . . . . . . . 23 90 5.2.2.2. AES_CBC_HMAC_SHA2 Decryption . . . . . . . . . . . 25 91 5.2.3. AES_128_CBC_HMAC_SHA_256 . . . . . . . . . . . . . . . 25 92 5.2.4. AES_192_CBC_HMAC_SHA_384 . . . . . . . . . . . . . . . 26 93 5.2.5. AES_256_CBC_HMAC_SHA_512 . . . . . . . . . . . . . . . 26 94 5.2.6. Content Encryption with AES_CBC_HMAC_SHA2 . . . . . . 27 95 5.3. Content Encryption with AES GCM . . . . . . . . . . . . . 27 96 6. Cryptographic Algorithms for Keys . . . . . . . . . . . . . . 28 97 6.1. "kty" (Key Type) Parameter Values . . . . . . . . . . . . 28 98 6.2. Parameters for Elliptic Curve Keys . . . . . . . . . . . . 28 99 6.2.1. Parameters for Elliptic Curve Public Keys . . . . . . 28 100 6.2.1.1. "crv" (Curve) Parameter . . . . . . . . . . . . . 29 101 6.2.1.2. "x" (X Coordinate) Parameter . . . . . . . . . . . 29 102 6.2.1.3. "y" (Y Coordinate) Parameter . . . . . . . . . . . 29 103 6.2.2. Parameters for Elliptic Curve Private Keys . . . . . . 29 104 6.2.2.1. "d" (ECC Private Key) Parameter . . . . . . . . . 30 105 6.3. Parameters for RSA Keys . . . . . . . . . . . . . . . . . 30 106 6.3.1. Parameters for RSA Public Keys . . . . . . . . . . . . 30 107 6.3.1.1. "n" (Modulus) Parameter . . . . . . . . . . . . . 30 108 6.3.1.2. "e" (Exponent) Parameter . . . . . . . . . . . . . 30 109 6.3.2. Parameters for RSA Private Keys . . . . . . . . . . . 30 110 6.3.2.1. "d" (Private Exponent) Parameter . . . . . . . . . 31 111 6.3.2.2. "p" (First Prime Factor) Parameter . . . . . . . . 31 112 6.3.2.3. "q" (Second Prime Factor) Parameter . . . . . . . 31 113 6.3.2.4. "dp" (First Factor CRT Exponent) Parameter . . . . 31 114 6.3.2.5. "dq" (Second Factor CRT Exponent) Parameter . . . 31 115 6.3.2.6. "qi" (First CRT Coefficient) Parameter . . . . . . 31 116 6.3.2.7. "oth" (Other Primes Info) Parameter . . . . . . . 32 117 6.4. Parameters for Symmetric Keys . . . . . . . . . . . . . . 32 118 6.4.1. "k" (Key Value) Parameter . . . . . . . . . . . . . . 33 119 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 33 120 7.1. JSON Web Signature and Encryption Algorithms Registry . . 34 121 7.1.1. Registration Template . . . . . . . . . . . . . . . . 34 122 7.1.2. Initial Registry Contents . . . . . . . . . . . . . . 35 123 7.2. JWE Header Parameter Names Registration . . . . . . . . . 41 124 7.2.1. Registry Contents . . . . . . . . . . . . . . . . . . 41 125 7.3. JSON Web Encryption Compression Algorithms Registry . . . 42 126 7.3.1. Registration Template . . . . . . . . . . . . . . . . 42 127 7.3.2. Initial Registry Contents . . . . . . . . . . . . . . 43 128 7.4. JSON Web Key Types Registry . . . . . . . . . . . . . . . 43 129 7.4.1. Registration Template . . . . . . . . . . . . . . . . 43 130 7.4.2. Initial Registry Contents . . . . . . . . . . . . . . 44 131 7.5. JSON Web Key Parameters Registration . . . . . . . . . . . 44 132 7.5.1. Registry Contents . . . . . . . . . . . . . . . . . . 44 133 7.6. JSON Web Key Elliptic Curve Registry . . . . . . . . . . . 47 134 7.6.1. Registration Template . . . . . . . . . . . . . . . . 47 135 7.6.2. Initial Registry Contents . . . . . . . . . . . . . . 48 136 8. Security Considerations . . . . . . . . . . . . . . . . . . . 48 137 8.1. Algorithms and Key Sizes will be Deprecated . . . . . . . 49 138 8.2. Key Lifetimes . . . . . . . . . . . . . . . . . . . . . . 49 139 8.3. RSAES-PKCS1-v1_5 Security Considerations . . . . . . . . . 49 140 8.4. AES GCM Security Considerations . . . . . . . . . . . . . 49 141 8.5. Plaintext JWS Security Considerations . . . . . . . . . . 50 142 8.6. Differences between Digital Signatures and MACs . . . . . 50 143 8.7. Denial of Service Attacks . . . . . . . . . . . . . . . . 51 144 8.8. Reusing Key Material when Encrypting Keys . . . . . . . . 51 145 8.9. Password Considerations . . . . . . . . . . . . . . . . . 51 147 9. Internationalization Considerations . . . . . . . . . . . . . 52 148 10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 52 149 10.1. Normative References . . . . . . . . . . . . . . . . . . . 52 150 10.2. Informative References . . . . . . . . . . . . . . . . . . 54 151 Appendix A. Algorithm Identifier Cross-Reference . . . . . . . . 55 152 A.1. Digital Signature/MAC Algorithm Identifier 153 Cross-Reference . . . . . . . . . . . . . . . . . . . . . 56 154 A.2. Key Management Algorithm Identifier Cross-Reference . . . 56 155 A.3. Content Encryption Algorithm Identifier Cross-Reference . 57 156 Appendix B. Test Cases for AES_CBC_HMAC_SHA2 Algorithms . . . . . 58 157 B.1. Test Cases for AES_128_CBC_HMAC_SHA_256 . . . . . . . . . 59 158 B.2. Test Cases for AES_192_CBC_HMAC_SHA_384 . . . . . . . . . 60 159 B.3. Test Cases for AES_256_CBC_HMAC_SHA_512 . . . . . . . . . 61 160 Appendix C. Example ECDH-ES Key Agreement Computation . . . . . . 62 161 Appendix D. Acknowledgements . . . . . . . . . . . . . . . . . . 64 162 Appendix E. Document History . . . . . . . . . . . . . . . . . . 65 163 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 74 165 1. Introduction 167 The JSON Web Algorithms (JWA) specification registers cryptographic 168 algorithms and identifiers to be used with the JSON Web Signature 169 (JWS) [JWS], JSON Web Encryption (JWE) [JWE], and JSON Web Key (JWK) 170 [JWK] specifications. It defines several IANA registries for these 171 identifiers. All these specifications utilize JavaScript Object 172 Notation (JSON) [RFC7159] based data structures. This specification 173 also describes the semantics and operations that are specific to 174 these algorithms and key types. 176 Registering the algorithms and identifiers here, rather than in the 177 JWS, JWE, and JWK specifications, is intended to allow them to remain 178 unchanged in the face of changes in the set of Required, Recommended, 179 Optional, and Deprecated algorithms over time. This also allows 180 changes to the JWS, JWE, and JWK specifications without changing this 181 document. 183 Names defined by this specification are short because a core goal is 184 for the resulting representations to be compact. 186 1.1. Notational Conventions 188 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 189 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 190 "OPTIONAL" in this document are to be interpreted as described in Key 191 words for use in RFCs to Indicate Requirement Levels [RFC2119]. If 192 these words are used without being spelled in uppercase then they are 193 to be interpreted with their normal natural language meanings. 195 BASE64URL(OCTETS) denotes the base64url encoding of OCTETS, per 196 Section 2. 198 UTF8(STRING) denotes the octets of the UTF-8 [RFC3629] representation 199 of STRING. 201 ASCII(STRING) denotes the octets of the ASCII [USASCII] 202 representation of STRING. 204 The concatenation of two values A and B is denoted as A || B. 206 2. Terminology 208 These terms defined by the JSON Web Signature (JWS) [JWS] 209 specification are incorporated into this specification: "JSON Web 210 Signature (JWS)", "JWS Header", "JWS Payload", "JWS Signature", "JWS 211 Protected Header", "Base64url Encoding", and "JWS Signing Input". 213 These terms defined by the JSON Web Encryption (JWE) [JWE] 214 specification are incorporated into this specification: "JSON Web 215 Encryption (JWE)", "Authenticated Encryption", "Plaintext", 216 "Ciphertext", "Additional Authenticated Data (AAD)", "Authentication 217 Tag", "Content Encryption Key (CEK)", "JWE Header", "JWE Encrypted 218 Key", "JWE Initialization Vector", "JWE Ciphertext", "JWE 219 Authentication Tag", "JWE Protected Header", "Key Management Mode", 220 "Key Encryption", "Key Wrapping", "Direct Key Agreement", "Key 221 Agreement with Key Wrapping", and "Direct Encryption". 223 These terms defined by the JSON Web Key (JWK) [JWK] specification are 224 incorporated into this specification: "JSON Web Key (JWK)" and "JSON 225 Web Key Set (JWK Set)". 227 These terms are defined for use by this specification: 229 Header Parameter 230 A name/value pair that is member of a JWS Header or JWE Header. 232 3. Cryptographic Algorithms for Digital Signatures and MACs 234 JWS uses cryptographic algorithms to digitally sign or create a 235 Message Authentication Codes (MAC) of the contents of the JWS Header 236 and the JWS Payload. 238 3.1. "alg" (Algorithm) Header Parameter Values for JWS 240 The table below is the set of "alg" (algorithm) header parameter 241 values defined by this specification for use with JWS, each of which 242 is explained in more detail in the following sections: 244 +---------------+------------------------------+--------------------+ 245 | alg Parameter | Digital Signature or MAC | Implementation | 246 | Value | Algorithm | Requirements | 247 +---------------+------------------------------+--------------------+ 248 | HS256 | HMAC using SHA-256 | Required | 249 | HS384 | HMAC using SHA-384 | Optional | 250 | HS512 | HMAC using SHA-512 | Optional | 251 | RS256 | RSASSA-PKCS-v1_5 using | Recommended | 252 | | SHA-256 | | 253 | RS384 | RSASSA-PKCS-v1_5 using | Optional | 254 | | SHA-384 | | 255 | RS512 | RSASSA-PKCS-v1_5 using | Optional | 256 | | SHA-512 | | 257 | ES256 | ECDSA using P-256 and | Recommended+ | 258 | | SHA-256 | | 259 | ES384 | ECDSA using P-384 and | Optional | 260 | | SHA-384 | | 261 | ES512 | ECDSA using P-521 and | Optional | 262 | | SHA-512 | | 263 | PS256 | RSASSA-PSS using SHA-256 and | Optional | 264 | | MGF1 with SHA-256 | | 265 | PS384 | RSASSA-PSS using SHA-384 and | Optional | 266 | | MGF1 with SHA-384 | | 267 | PS512 | RSASSA-PSS using SHA-512 and | Optional | 268 | | MGF1 with SHA-512 | | 269 | none | No digital signature or MAC | Optional | 270 | | performed | | 271 +---------------+------------------------------+--------------------+ 273 The use of "+" in the Implementation Requirements indicates that the 274 requirement strength is likely to be increased in a future version of 275 the specification. 277 See Appendix A.1 for a table cross-referencing the JWS digital 278 signature and MAC "alg" (algorithm) values defined in this 279 specification with the equivalent identifiers used by other standards 280 and software packages. 282 3.2. HMAC with SHA-2 Functions 284 Hash-based Message Authentication Codes (HMACs) enable one to use a 285 secret plus a cryptographic hash function to generate a Message 286 Authentication Code (MAC). This can be used to demonstrate that 287 whoever generated the MAC was in possession of the MAC key. The 288 algorithm for implementing and validating HMACs is provided in RFC 289 2104 [RFC2104]. 291 A key of the same size as the hash output (for instance, 256 bits for 292 "HS256") or larger MUST be used with this algorithm. 294 The HMAC SHA-256 MAC is generated per RFC 2104, using SHA-256 as the 295 hash algorithm "H", using the JWS Signing Input as the "text" value, 296 and using the shared key. The HMAC output value is the JWS 297 Signature. 299 The following "alg" (algorithm) Header Parameter values are used to 300 indicate that the JWS Signature is an HMAC value computed using the 301 corresponding algorithm: 303 +---------------------+--------------------+ 304 | alg Parameter Value | MAC Algorithm | 305 +---------------------+--------------------+ 306 | HS256 | HMAC using SHA-256 | 307 | HS384 | HMAC using SHA-384 | 308 | HS512 | HMAC using SHA-512 | 309 +---------------------+--------------------+ 311 The HMAC SHA-256 MAC for a JWS is validated by computing an HMAC 312 value per RFC 2104, using SHA-256 as the hash algorithm "H", using 313 the received JWS Signing Input as the "text" value, and using the 314 shared key. This computed HMAC value is then compared to the result 315 of base64url decoding the received encoded JWS Signature value. 316 Alternatively, the computed HMAC value can be base64url encoded and 317 compared to the received encoded JWS Signature value, as this 318 comparison produces the same result as comparing the unencoded 319 values. In either case, if the values match, the HMAC has been 320 validated. 322 Securing content and validation with the HMAC SHA-384 and HMAC SHA- 323 512 algorithms is performed identically to the procedure for HMAC 324 SHA-256 -- just using the corresponding hash algorithms with 325 correspondingly larger minimum key sizes and result values: 384 bits 326 each for HMAC SHA-384 and 512 bits each for HMAC SHA-512. 328 An example using this algorithm is shown in Appendix A.1 of [JWS]. 330 3.3. Digital Signature with RSASSA-PKCS1-V1_5 332 This section defines the use of the RSASSA-PKCS1-V1_5 digital 333 signature algorithm as defined in Section 8.2 of RFC 3447 [RFC3447] 334 (commonly known as PKCS #1), using SHA-2 [SHS] hash functions. 336 A key of size 2048 bits or larger MUST be used with these algorithms. 338 The RSASSA-PKCS1-V1_5 SHA-256 digital signature is generated as 339 follows: Generate a digital signature of the JWS Signing Input using 340 RSASSA-PKCS1-V1_5-SIGN and the SHA-256 hash function with the desired 341 private key. This is the JWS Signature value. 343 The following "alg" (algorithm) Header Parameter values are used to 344 indicate that the JWS Signature is a digital signature value computed 345 using the corresponding algorithm: 347 +---------------------+--------------------------------+ 348 | alg Parameter Value | Digital Signature Algorithm | 349 +---------------------+--------------------------------+ 350 | RS256 | RSASSA-PKCS-v1_5 using SHA-256 | 351 | RS384 | RSASSA-PKCS-v1_5 using SHA-384 | 352 | RS512 | RSASSA-PKCS-v1_5 using SHA-512 | 353 +---------------------+--------------------------------+ 355 The RSASSA-PKCS1-V1_5 SHA-256 digital signature for a JWS is 356 validated as follows: Submit the JWS Signing Input, the JWS 357 Signature, and the public key corresponding to the private key used 358 by the signer to the RSASSA-PKCS1-V1_5-VERIFY algorithm using SHA-256 359 as the hash function. 361 Signing and validation with the RSASSA-PKCS1-V1_5 SHA-384 and RSASSA- 362 PKCS1-V1_5 SHA-512 algorithms is performed identically to the 363 procedure for RSASSA-PKCS1-V1_5 SHA-256 -- just using the 364 corresponding hash algorithms instead of SHA-256. 366 An example using this algorithm is shown in Appendix A.2 of [JWS]. 368 3.4. Digital Signature with ECDSA 370 The Elliptic Curve Digital Signature Algorithm (ECDSA) [DSS] provides 371 for the use of Elliptic Curve cryptography, which is able to provide 372 equivalent security to RSA cryptography but using shorter key sizes 373 and with greater processing speed. This means that ECDSA digital 374 signatures will be substantially smaller in terms of length than 375 equivalently strong RSA digital signatures. 377 This specification defines the use of ECDSA with the P-256 curve and 378 the SHA-256 cryptographic hash function, ECDSA with the P-384 curve 379 and the SHA-384 hash function, and ECDSA with the P-521 curve and the 380 SHA-512 hash function. The P-256, P-384, and P-521 curves are 381 defined in [DSS]. 383 The ECDSA P-256 SHA-256 digital signature is generated as follows: 385 1. Generate a digital signature of the JWS Signing Input using ECDSA 386 P-256 SHA-256 with the desired private key. The output will be 387 the pair (R, S), where R and S are 256 bit unsigned integers. 389 2. Turn R and S into octet sequences in big endian order, with each 390 array being be 32 octets long. The octet sequence 391 representations MUST NOT be shortened to omit any leading zero 392 octets contained in the values. 394 3. Concatenate the two octet sequences in the order R and then S. 395 (Note that many ECDSA implementations will directly produce this 396 concatenation as their output.) 398 4. The resulting 64 octet sequence is the JWS Signature value. 400 The following "alg" (algorithm) Header Parameter values are used to 401 indicate that the JWS Signature is a digital signature value computed 402 using the corresponding algorithm: 404 +---------------------+-------------------------------+ 405 | alg Parameter Value | Digital Signature Algorithm | 406 +---------------------+-------------------------------+ 407 | ES256 | ECDSA using P-256 and SHA-256 | 408 | ES384 | ECDSA using P-384 and SHA-384 | 409 | ES512 | ECDSA using P-521 and SHA-512 | 410 +---------------------+-------------------------------+ 412 The ECDSA P-256 SHA-256 digital signature for a JWS is validated as 413 follows: 415 1. The JWS Signature value MUST be a 64 octet sequence. If it is 416 not a 64 octet sequence, the validation has failed. 418 2. Split the 64 octet sequence into two 32 octet sequences. The 419 first octet sequence represents R and the second S. The values R 420 and S are represented as octet sequences using the Integer-to- 421 OctetString Conversion defined in Section 2.3.7 of SEC1 [SEC1] 422 (in big endian octet order). 424 3. Submit the JWS Signing Input R, S and the public key (x, y) to 425 the ECDSA P-256 SHA-256 validator. 427 Signing and validation with the ECDSA P-384 SHA-384 and ECDSA P-521 428 SHA-512 algorithms is performed identically to the procedure for 429 ECDSA P-256 SHA-256 -- just using the corresponding hash algorithms 430 with correspondingly larger result values. For ECDSA P-384 SHA-384, 431 R and S will be 384 bits each, resulting in a 96 octet sequence. For 432 ECDSA P-521 SHA-512, R and S will be 521 bits each, resulting in a 433 132 octet sequence. 435 Examples using these algorithms are shown in Appendices A.3 and A.4 436 of [JWS]. 438 3.5. Digital Signature with RSASSA-PSS 440 This section defines the use of the RSASSA-PSS digital signature 441 algorithm as defined in Section 8.1 of RFC 3447 [RFC3447] with the 442 MGF1 mask generation function and SHA-2 hash functions, always using 443 the same hash function for both the RSASSA-PSS hash function and the 444 MGF1 hash function. The size of the salt value is the same size as 445 the hash function output. All other algorithm parameters use the 446 defaults specified in Section A.2.3 of RFC 3447. 448 A key of size 2048 bits or larger MUST be used with this algorithm. 450 The RSASSA-PSS SHA-256 digital signature is generated as follows: 451 Generate a digital signature of the JWS Signing Input using RSASSA- 452 PSS-SIGN, the SHA-256 hash function, and the MGF1 mask generation 453 function with SHA-256 with the desired private key. This is the JWS 454 signature value. 456 The following "alg" (algorithm) Header Parameter values are used to 457 indicate that the JWS Signature is a digital signature value computed 458 using the corresponding algorithm: 460 +---------------------+---------------------------------------------+ 461 | alg Parameter Value | Digital Signature Algorithm | 462 +---------------------+---------------------------------------------+ 463 | PS256 | RSASSA-PSS using SHA-256 and MGF1 with | 464 | | SHA-256 | 465 | PS384 | RSASSA-PSS using SHA-384 and MGF1 with | 466 | | SHA-384 | 467 | PS512 | RSASSA-PSS using SHA-512 and MGF1 with | 468 | | SHA-512 | 469 +---------------------+---------------------------------------------+ 471 The RSASSA-PSS SHA-256 digital signature for a JWS is validated as 472 follows: Submit the JWS Signing Input, the JWS Signature, and the 473 public key corresponding to the private key used by the signer to the 474 RSASSA-PSS-VERIFY algorithm using SHA-256 as the hash function and 475 using MGF1 as the mask generation function with SHA-256. 477 Signing and validation with the RSASSA-PSS SHA-384 and RSASSA-PSS 478 SHA-512 algorithms is performed identically to the procedure for 479 RSASSA-PSS SHA-256 -- just using the alternative hash algorithm in 480 both roles. 482 3.6. Using the Algorithm "none" 484 JWSs MAY also be created that do not provide integrity protection. 485 Such a JWS is called a "Plaintext JWS". A Plaintext JWS MUST use the 486 "alg" value "none", and is formatted identically to other JWSs, but 487 MUST use the empty octet sequence as its JWS Signature value. 488 Receivers MUST verify that the JWS Signature value is the empty octet 489 sequence. See Section 8.5 for security considerations associated 490 with using this algorithm. 492 4. Cryptographic Algorithms for Key Management 494 JWE uses cryptographic algorithms to encrypt or determine the Content 495 Encryption Key (CEK). 497 4.1. "alg" (Algorithm) Header Parameter Values for JWE 499 The table below is the set of "alg" (algorithm) Header Parameter 500 values that are defined by this specification for use with JWE. 501 These algorithms are used to encrypt the CEK, producing the JWE 502 Encrypted Key, or to use key agreement to agree upon the CEK. 504 +-------------------+-----------------+------------+----------------+ 505 | alg Parameter | Key Management | Additional | Implementation | 506 | Value | Algorithm | Header | Requirements | 507 | | | Parameters | | 508 +-------------------+-----------------+------------+----------------+ 509 | RSA1_5 | RSAES-PKCS1-V1_ | (none) | Required | 510 | | 5 | | | 511 | RSA-OAEP | RSAES OAEP | (none) | Optional | 512 | | using default | | | 513 | | parameters | | | 514 | RSA-OAEP-256 | RSAES OAEP | (none) | Optional | 515 | | using SHA-256 | | | 516 | | and MGF1 with | | | 517 | | SHA-256 | | | 518 | A128KW | AES Key Wrap | (none) | Recommended | 519 | | with default | | | 520 | | initial value | | | 521 | | using 128 bit | | | 522 | | key | | | 523 | A192KW | AES Key Wrap | (none) | Optional | 524 | | with default | | | 525 | | initial value | | | 526 | | using 192 bit | | | 527 | | key | | | 528 | A256KW | AES Key Wrap | (none) | Recommended | 529 | | with default | | | 530 | | initial value | | | 531 | | using 256 bit | | | 532 | | key | | | 533 | dir | Direct use of a | (none) | Recommended | 534 | | shared | | | 535 | | symmetric key | | | 536 | | as the CEK | | | 537 | ECDH-ES | Elliptic Curve | "epk", | Recommended+ | 538 | | Diffie-Hellman | "apu", | | 539 | | Ephemeral | "apv" | | 540 | | Static key | | | 541 | | agreement using | | | 542 | | Concat KDF | | | 543 | ECDH-ES+A128KW | ECDH-ES using | "epk", | Recommended | 544 | | Concat KDF and | "apu", | | 545 | | CEK wrapped | "apv" | | 546 | | with "A128KW" | | | 547 | ECDH-ES+A192KW | ECDH-ES using | "epk", | Optional | 548 | | Concat KDF and | "apu", | | 549 | | CEK wrapped | "apv" | | 550 | | with "A192KW" | | | 551 | ECDH-ES+A256KW | ECDH-ES using | "epk", | Recommended | 552 | | Concat KDF and | "apu", | | 553 | | CEK wrapped | "apv" | | 554 | | with "A256KW" | | | 555 | A128GCMKW | Key wrapping | "iv", | Optional | 556 | | with AES GCM | "tag" | | 557 | | using 128 bit | | | 558 | | key | | | 559 | A192GCMKW | Key wrapping | "iv", | Optional | 560 | | with AES GCM | "tag" | | 561 | | using 192 bit | | | 562 | | key | | | 563 | A256GCMKW | Key wrapping | "iv", | Optional | 564 | | with AES GCM | "tag" | | 565 | | using 256 bit | | | 566 | | key | | | 567 | PBES2-HS256+A128K | PBES2 with HMAC | "p2s", | Optional | 568 | W | SHA-256 and | "p2c" | | 569 | | "A128KW" | | | 570 | | wrapping | | | 571 | PBES2-HS384+A192K | PBES2 with HMAC | "p2s", | Optional | 572 | W | SHA-384 and | "p2c" | | 573 | | "A192KW" | | | 574 | | wrapping | | | 575 | PBES2-HS512+A256K | PBES2 with HMAC | "p2s", | Optional | 576 | W | SHA-512 and | "p2c" | | 577 | | "A256KW" | | | 578 | | wrapping | | | 579 +-------------------+-----------------+------------+----------------+ 581 The Additional Header Parameters column indicates what additional 582 Header Parameters are used by the algorithm, beyond "alg", which all 583 use. All but "dir" and "ECDH-ES" also produce a JWE Encrypted Key 584 value. 586 The use of "+" in the Implementation Requirements indicates that the 587 requirement strength is likely to be increased in a future version of 588 the specification. 590 See Appendix A.2 for a table cross-referencing the JWE "alg" 591 (algorithm) values defined in this specification with the equivalent 592 identifiers used by other standards and software packages. 594 4.2. Key Encryption with RSAES-PKCS1-V1_5 596 This section defines the specifics of encrypting a JWE CEK with 597 RSAES-PKCS1-V1_5 [RFC3447]. The "alg" Header Parameter value 598 "RSA1_5" is used for this algorithm. 600 A key of size 2048 bits or larger MUST be used with this algorithm. 602 An example using this algorithm is shown in Appendix A.2 of [JWE]. 604 4.3. Key Encryption with RSAES OAEP 606 This section defines the specifics of encrypting a JWE CEK with RSAES 607 using Optimal Asymmetric Encryption Padding (OAEP) [RFC3447]. Two 608 sets of parameters for using OAEP are defined, which use different 609 hash functions. In the first case, the default parameters specified 610 by RFC 3447 in Section A.2.1 are used. (Those default parameters are 611 the SHA-1 hash function and the MGF1 with SHA-1 mask generation 612 function.) In the second case, the SHA-256 hash function and the 613 MGF1 with SHA-256 mask generation function are used. 615 The following "alg" (algorithm) Header Parameter values are used to 616 indicate that the JWE Encrypted Key is the result of encrypting the 617 CEK using the corresponding algorithm: 619 +---------------------+---------------------------------------------+ 620 | alg Parameter Value | Key Management Algorithm | 621 +---------------------+---------------------------------------------+ 622 | RSA-OAEP | RSAES OAEP using default parameters | 623 | RSA-OAEP-256 | RSAES OAEP using SHA-256 and MGF1 with | 624 | | SHA-256 | 625 +---------------------+---------------------------------------------+ 627 A key of size 2048 bits or larger MUST be used with these algorithms. 629 An example using RSAES OAEP with the default parameters is shown in 630 Appendix A.1 of [JWE]. 632 4.4. Key Wrapping with AES Key Wrap 634 This section defines the specifics of encrypting a JWE CEK with the 635 Advanced Encryption Standard (AES) Key Wrap Algorithm [RFC3394] using 636 the default initial value specified in Section 2.2.3.1. 638 The following "alg" (algorithm) Header Parameter values are used to 639 indicate that the JWE Encrypted Key is the result of encrypting the 640 CEK using the corresponding algorithm and key size: 642 +------------------+------------------------------------------------+ 643 | alg Parameter | Key Management Algorithm | 644 | Value | | 645 +------------------+------------------------------------------------+ 646 | A128KW | AES Key Wrap with default initial value using | 647 | | 128 bit key | 648 | A192KW | AES Key Wrap with default initial value using | 649 | | 192 bit key | 650 | A256KW | AES Key Wrap with default initial value using | 651 | | 256 bit key | 652 +------------------+------------------------------------------------+ 654 An example using this algorithm is shown in Appendix A.3 of [JWE]. 656 4.5. Direct Encryption with a Shared Symmetric Key 658 This section defines the specifics of directly performing symmetric 659 key encryption without performing a key wrapping step. In this case, 660 the shared symmetric key is used directly as the Content Encryption 661 Key (CEK) value for the "enc" algorithm. An empty octet sequence is 662 used as the JWE Encrypted Key value. The "alg" Header Parameter 663 value "dir" is used in this case. 665 Refer to the security considerations on key lifetimes in Section 8.2 666 and AES GCM in Section 8.4 when considering utilizing direct 667 encryption. 669 4.6. Key Agreement with Elliptic Curve Diffie-Hellman Ephemeral Static 670 (ECDH-ES) 672 This section defines the specifics of key agreement with Elliptic 673 Curve Diffie-Hellman Ephemeral Static [RFC6090], in combination with 674 the Concat KDF, as defined in Section 5.8.1 of [NIST.800-56A]. The 675 key agreement result can be used in one of two ways: 677 1. directly as the Content Encryption Key (CEK) for the "enc" 678 algorithm, in the Direct Key Agreement mode, or 680 2. as a symmetric key used to wrap the CEK with the "A128KW", 681 "A192KW", or "A256KW" algorithms, in the Key Agreement with Key 682 Wrapping mode. 684 A new ephemeral public key value MUST be generated for each key 685 agreement operation. 687 In Direct Key Agreement mode, the output of the Concat KDF MUST be a 688 key of the same length as that used by the "enc" algorithm. In this 689 case, the empty octet sequence is used as the JWE Encrypted Key 690 value. The "alg" Header Parameter value "ECDH-ES" is used in the 691 Direct Key Agreement mode. 693 In Key Agreement with Key Wrapping mode, the output of the Concat KDF 694 MUST be a key of the length needed for the specified key wrapping 695 algorithm. In this case, the JWE Encrypted Key is the CEK wrapped 696 with the agreed upon key. 698 The following "alg" (algorithm) Header Parameter values are used to 699 indicate that the JWE Encrypted Key is the result of encrypting the 700 CEK using the result of the key agreement algorithm as the key 701 encryption key for the corresponding key wrapping algorithm: 703 +-------------------+-----------------------------------------------+ 704 | alg Parameter | Key Management Algorithm | 705 | Value | | 706 +-------------------+-----------------------------------------------+ 707 | ECDH-ES+A128KW | ECDH-ES using Concat KDF and CEK wrapped with | 708 | | "A128KW" | 709 | ECDH-ES+A192KW | ECDH-ES using Concat KDF and CEK wrapped with | 710 | | "A192KW" | 711 | ECDH-ES+A256KW | ECDH-ES using Concat KDF and CEK wrapped with | 712 | | "A256KW" | 713 +-------------------+-----------------------------------------------+ 715 4.6.1. Header Parameters Used for ECDH Key Agreement 717 The following Header Parameter names are used for key agreement as 718 defined below. 720 4.6.1.1. "epk" (Ephemeral Public Key) Header Parameter 722 The "epk" (ephemeral public key) value created by the originator for 723 the use in key agreement algorithms. This key is represented as a 724 JSON Web Key [JWK] public key value. It MUST contain only public key 725 parameters and SHOULD contain only the minimum JWK parameters 726 necessary to represent the key; other JWK parameters included can be 727 checked for consistency and honored or can be ignored. This Header 728 Parameter MUST be present and MUST be understood and processed by 729 implementations when these algorithms are used. 731 4.6.1.2. "apu" (Agreement PartyUInfo) Header Parameter 733 The "apu" (agreement PartyUInfo) value for key agreement algorithms 734 using it (such as "ECDH-ES"), represented as a base64url encoded 735 string. When used, the PartyUInfo value contains information about 736 the sender. Use of this Header Parameter is OPTIONAL. This Header 737 Parameter MUST be understood and processed by implementations when 738 these algorithms are used. 740 4.6.1.3. "apv" (Agreement PartyVInfo) Header Parameter 742 The "apv" (agreement PartyVInfo) value for key agreement algorithms 743 using it (such as "ECDH-ES"), represented as a base64url encoded 744 string. When used, the PartyVInfo value contains information about 745 the receiver. Use of this Header Parameter is OPTIONAL. This Header 746 Parameter MUST be understood and processed by implementations when 747 these algorithms are used. 749 4.6.2. Key Derivation for ECDH Key Agreement 751 The key derivation process derives the agreed upon key from the 752 shared secret Z established through the ECDH algorithm, per Section 753 6.2.2.2 of [NIST.800-56A]. 755 Key derivation is performed using the Concat KDF, as defined in 756 Section 5.8.1 of [NIST.800-56A], where the Digest Method is SHA-256. 757 The Concat KDF parameters are set as follows: 759 Z 760 This is set to the representation of the shared secret Z as an 761 octet sequence. 763 keydatalen 764 This is set to the number of bits in the desired output key. For 765 "ECDH-ES", this is length of the key used by the "enc" algorithm. 766 For "ECDH-ES+A128KW", "ECDH-ES+A192KW", and "ECDH-ES+A256KW", this 767 is 128, 192, and 256, respectively. 769 AlgorithmID 770 The AlgorithmID value is of the form Datalen || Data, where Data 771 is a variable-length string of zero or more octets, and Datalen is 772 a fixed-length, big endian 32 bit counter that indicates the 773 length (in octets) of Data. In the Direct Key Agreement case, 774 Data is set to the octets of the UTF-8 representation of the "enc" 775 Header Parameter value. In the Key Agreement with Key Wrapping 776 case, Data is set to the octets of the UTF-8 representation of the 777 "alg" Header Parameter value. 779 PartyUInfo 780 The PartyUInfo value is of the form Datalen || Data, where Data is 781 a variable-length string of zero or more octets, and Datalen is a 782 fixed-length, big endian 32 bit counter that indicates the length 783 (in octets) of Data. If an "apu" (agreement PartyUInfo) Header 784 Parameter is present, Data is set to the result of base64url 785 decoding the "apu" value and Datalen is set to the number of 786 octets in Data. Otherwise, Datalen is set to 0 and Data is set to 787 the empty octet sequence. 789 PartyVInfo 790 The PartyVInfo value is of the form Datalen || Data, where Data is 791 a variable-length string of zero or more octets, and Datalen is a 792 fixed-length, big endian 32 bit counter that indicates the length 793 (in octets) of Data. If an "apv" (agreement PartyVInfo) Header 794 Parameter is present, Data is set to the result of base64url 795 decoding the "apv" value and Datalen is set to the number of 796 octets in Data. Otherwise, Datalen is set to 0 and Data is set to 797 the empty octet sequence. 799 SuppPubInfo 800 This is set to the keydatalen represented as a 32 bit big endian 801 integer. 803 SuppPrivInfo 804 This is set to the empty octet sequence. 806 Applications need to specify how the "apu" and "apv" parameters are 807 used for that application. The "apu" and "apv" values MUST be 808 distinct, when used. Applications wishing to conform to 809 [NIST.800-56A] need to provide values that meet the requirements of 810 that document, e.g., by using values that identify the sender and 811 recipient. Alternatively, applications MAY conduct key derivation in 812 a manner similar to The Diffie-Hellman Key Agreement Method 813 [RFC2631]: In that case, the "apu" field MAY either be omitted or 814 represent a random 512-bit value (analogous to PartyAInfo in 815 Ephemeral-Static mode in RFC 2631) and the "apv" field SHOULD NOT be 816 present. 818 See Appendix C for an example key agreement computation using this 819 method. 821 4.7. Key Encryption with AES GCM 823 This section defines the specifics of encrypting a JWE Content 824 Encryption Key (CEK) with Advanced Encryption Standard (AES) in 825 Galois/Counter Mode (GCM) [AES] [NIST.800-38D]. 827 Use of an Initialization Vector of size 96 bits is REQUIRED with this 828 algorithm. The Initialization Vector is represented in base64url 829 encoded form as the "iv" (initialization vector) Header Parameter 830 value. 832 The Additional Authenticated Data value used is the empty octet 833 string. 835 The requested size of the Authentication Tag output MUST be 128 bits, 836 regardless of the key size. 838 The JWE Encrypted Key value is the Ciphertext output. 840 The Authentication Tag output is represented in base64url encoded 841 form as the "tag" (authentication tag) Header Parameter value. 843 The following "alg" (algorithm) Header Parameter values are used to 844 indicate that the JWE Encrypted Key is the result of encrypting the 845 CEK using the corresponding algorithm and key size: 847 +---------------------+---------------------------------------------+ 848 | alg Parameter Value | Key Management Algorithm | 849 +---------------------+---------------------------------------------+ 850 | A128GCMKW | Key wrapping with AES GCM using 128 bit key | 851 | A192GCMKW | Key wrapping with AES GCM using 192 bit key | 852 | A256GCMKW | Key wrapping with AES GCM using 256 bit key | 853 +---------------------+---------------------------------------------+ 855 4.7.1. Header Parameters Used for AES GCM Key Encryption 857 The following Header Parameters are used for AES GCM key encryption. 859 4.7.1.1. "iv" (Initialization Vector) Header Parameter 861 The "iv" (initialization vector) Header Parameter value is the 862 base64url encoded representation of the Initialization Vector value 863 used for the key encryption operation. This Header Parameter MUST be 864 present and MUST be understood and processed by implementations when 865 these algorithms are used. 867 4.7.1.2. "tag" (Authentication Tag) Header Parameter 869 The "tag" (authentication tag) Header Parameter value is the 870 base64url encoded representation of the Authentication Tag value 871 resulting from the key encryption operation. This Header Parameter 872 MUST be present and MUST be understood and processed by 873 implementations when these algorithms are used. 875 4.8. Key Encryption with PBES2 877 This section defines the specifies of performing password-based 878 encryption of a JWE CEK, by first deriving a key encryption key from 879 a user-supplied password using PBES2 schemes as specified in Section 880 6.2 of [RFC2898], then by encrypting the JWE CEK using the derived 881 key. 883 These algorithms use HMAC SHA-2 algorithms as the Pseudo-Random 884 Function (PRF) for the PBKDF2 key derivation and AES Key Wrap 885 [RFC3394] for the encryption scheme. The PBES2 password input is an 886 octet sequence; if the password to be used is represented as a text 887 string rather than an octet sequence, the UTF-8 encoding of the text 888 string MUST be used as the octet sequence. The salt parameter MUST 889 be computed from the "p2s" (PBES2 salt input) Header Parameter value 890 and the "alg" (algorithm) Header Parameter value as specified in the 891 "p2s" definition below. The iteration count parameter MUST be 892 provided as the "p2c" Header Parameter value. The algorithms 893 respectively use HMAC SHA-256, HMAC SHA-384, and HMAC SHA-512 as the 894 PRF and use 128, 192, and 256 bit AES Key Wrap keys. Their derived- 895 key lengths respectively are 16, 24, and 32 octets. 897 The following "alg" (algorithm) Header Parameter values are used to 898 indicate that the JWE Encrypted Key is the result of encrypting the 899 CEK using the result of the corresponding password-based encryption 900 algorithm as the key encryption key for the corresponding key 901 wrapping algorithm: 903 +---------------------+---------------------------------------------+ 904 | alg Parameter Value | Key Management Algorithm | 905 +---------------------+---------------------------------------------+ 906 | PBES2-HS256+A128KW | PBES2 with HMAC SHA-256 and "A128KW" | 907 | | wrapping | 908 | PBES2-HS384+A192KW | PBES2 with HMAC SHA-384 and "A192KW" | 909 | | wrapping | 910 | PBES2-HS512+A256KW | PBES2 with HMAC SHA-512 and "A256KW" | 911 | | wrapping | 912 +---------------------+---------------------------------------------+ 914 See Appendix C of JSON Web Key (JWK) [JWK] for an example key 915 encryption computation using "PBES2-HS256+A128KW". 917 4.8.1. Header Parameters Used for PBES2 Key Encryption 919 The following Header Parameters are used for Key Encryption with 920 PBES2. 922 4.8.1.1. "p2s" (PBES2 salt input) Parameter 924 The "p2s" (PBES2 salt input) Header Parameter encodes a Salt Input 925 value, which is used as part of the PBKDF2 salt value. The "p2s" 926 value is BASE64URL(Salt Input). This Header Parameter MUST be 927 present and MUST be understood and processed by implementations when 928 these algorithms are used. 930 The salt expands the possible keys that can be derived from a given 931 password. A Salt Input value containing 8 or more octets MUST be 932 used. A new Salt Input value MUST be generated randomly for every 933 encryption operation; see [RFC4086] for considerations on generating 934 random values. The salt value used is (UTF8(Alg) || 0x00 || Salt 935 Input), where Alg is the "alg" Header Parameter value. 937 4.8.1.2. "p2c" (PBES2 count) Parameter 939 The "p2c" (PBES2 count) Header Parameter contains the PBKDF2 940 iteration count, represented as a positive integer. This Header 941 Parameter MUST be present and MUST be understood and processed by 942 implementations when these algorithms are used. 944 The iteration count adds computational expense, ideally compounded by 945 the possible range of keys introduced by the salt. A minimum 946 iteration count of 1000 is RECOMMENDED. 948 5. Cryptographic Algorithms for Content Encryption 950 JWE uses cryptographic algorithms to encrypt the Plaintext. 952 5.1. "enc" (Encryption Algorithm) Header Parameter Values for JWE 954 The table below is the set of "enc" (encryption algorithm) Header 955 Parameter values that are defined by this specification for use with 956 JWE. These algorithms are used to encrypt the Plaintext, which 957 produces the Ciphertext. 959 +-------------+------------------------+------------+---------------+ 960 | enc | Content Encryption | Additional | Implementatio | 961 | Parameter | Algorithm | Header | nRequirements | 962 | Value | | Parameters | | 963 +-------------+------------------------+------------+---------------+ 964 | A128CBC-HS2 | AES_128_CBC_HMAC_SHA_2 | (none) | Required | 965 | 56 | 56 authenticated | | | 966 | | encryption algorithm, | | | 967 | | as defined in | | | 968 | | Section 5.2.3 | | | 969 | A192CBC-HS3 | AES_192_CBC_HMAC_SHA_3 | (none) | Optional | 970 | 84 | 84 authenticated | | | 971 | | encryption algorithm, | | | 972 | | as defined in | | | 973 | | Section 5.2.4 | | | 974 | A256CBC-HS5 | AES_256_CBC_HMAC_SHA_5 | (none) | Required | 975 | 12 | 12 authenticated | | | 976 | | encryption algorithm, | | | 977 | | as defined in | | | 978 | | Section 5.2.5 | | | 979 | A128GCM | AES GCM using 128 bit | (none) | Recommended | 980 | | key | | | 981 | A192GCM | AES GCM using 192 bit | (none) | Optional | 982 | | key | | | 983 | A256GCM | AES GCM using 256 bit | (none) | Recommended | 984 | | key | | | 985 +-------------+------------------------+------------+---------------+ 987 The Additional Header Parameters column indicates what additional 988 Header Parameters are used by the algorithm, beyond "enc", which all 989 use. All also use a JWE Initialization Vector value and produce JWE 990 Ciphertext and JWE Authentication Tag values. 992 See Appendix A.3 for a table cross-referencing the JWE "enc" 993 (encryption algorithm) values defined in this specification with the 994 equivalent identifiers used by other standards and software packages. 996 5.2. AES_CBC_HMAC_SHA2 Algorithms 998 This section defines a family of authenticated encryption algorithms 999 built using a composition of Advanced Encryption Standard (AES) in 1000 Cipher Block Chaining (CBC) mode with PKCS #5 padding [AES] 1001 [NIST.800-38A] operations and HMAC [RFC2104] [SHS] operations. This 1002 algorithm family is called AES_CBC_HMAC_SHA2. It also defines three 1003 instances of this family, the first using 128 bit CBC keys and HMAC 1004 SHA-256, the second using 192 bit CBC keys and HMAC SHA-384, and the 1005 third using 256 bit CBC keys and HMAC SHA-512. Test cases for these 1006 algorithms can be found in Appendix B. 1008 These algorithms are based upon Authenticated Encryption with AES-CBC 1009 and HMAC-SHA [I-D.mcgrew-aead-aes-cbc-hmac-sha2], performing the same 1010 cryptographic computations, but with the Initialization Vector and 1011 Authentication Tag values remaining separate, rather than being 1012 concatenated with the Ciphertext value in the output representation. 1013 This option is discussed in Appendix B of that specification. This 1014 algorithm family is a generalization of the algorithm family in 1015 [I-D.mcgrew-aead-aes-cbc-hmac-sha2], and can be used to implement 1016 those algorithms. 1018 5.2.1. Conventions Used in Defining AES_CBC_HMAC_SHA2 1020 We use the following notational conventions. 1022 CBC-PKCS5-ENC(X, P) denotes the AES CBC encryption of P using PKCS 1023 #5 padding using the cipher with the key X. 1025 MAC(Y, M) denotes the application of the Message Authentication 1026 Code (MAC) to the message M, using the key Y. 1028 5.2.2. Generic AES_CBC_HMAC_SHA2 Algorithm 1030 This section defines AES_CBC_HMAC_SHA2 in a manner that is 1031 independent of the AES CBC key size or hash function to be used. 1032 Section 5.2.2.1 and Section 5.2.2.2 define the generic encryption and 1033 decryption algorithms. Section 5.2.3 and Section 5.2.5 define 1034 instances of AES_CBC_HMAC_SHA2 that specify those details. 1036 5.2.2.1. AES_CBC_HMAC_SHA2 Encryption 1038 The authenticated encryption algorithm takes as input four octet 1039 strings: a secret key K, a plaintext P, additional authenticated data 1040 A, and an initialization vector IV. The authenticated ciphertext 1041 value E and the authentication tag value T are provided as outputs. 1042 The data in the plaintext are encrypted and authenticated, and the 1043 additional authenticated data are authenticated, but not encrypted. 1045 The encryption process is as follows, or uses an equivalent set of 1046 steps: 1048 1. The secondary keys MAC_KEY and ENC_KEY are generated from the 1049 input key K as follows. Each of these two keys is an octet 1050 string. 1052 MAC_KEY consists of the initial MAC_KEY_LEN octets of K, in 1053 order. 1055 ENC_KEY consists of the final ENC_KEY_LEN octets of K, in 1056 order. 1058 Here we denote the number of octets in the MAC_KEY as 1059 MAC_KEY_LEN, and the number of octets in ENC_KEY as ENC_KEY_LEN; 1060 the values of these parameters are specified by the AEAD 1061 algorithms (in Section 5.2.3 and Section 5.2.5). The number of 1062 octets in the input key K is the sum of MAC_KEY_LEN and 1063 ENC_KEY_LEN. When generating the secondary keys from K, MAC_KEY 1064 and ENC_KEY MUST NOT overlap. Note that the MAC key comes before 1065 the encryption key in the input key K; this is in the opposite 1066 order of the algorithm names in the identifier 1067 "AES_CBC_HMAC_SHA2". 1069 2. The Initialization Vector (IV) used is a 128 bit value generated 1070 randomly or pseudorandomly for use in the cipher. 1072 3. The plaintext is CBC encrypted using PKCS #5 padding using 1073 ENC_KEY as the key, and the IV. We denote the ciphertext output 1074 from this step as E. 1076 4. The octet string AL is equal to the number of bits in A expressed 1077 as a 64-bit unsigned integer in network byte order. 1079 5. A message authentication tag T is computed by applying HMAC 1080 [RFC2104] to the following data, in order: 1082 the additional authenticated data A, 1084 the initialization vector IV, 1086 the ciphertext E computed in the previous step, and 1088 the octet string AL defined above. 1090 The string MAC_KEY is used as the MAC key. We denote the output 1091 of the MAC computed in this step as M. The first T_LEN bits of M 1092 are used as T. 1094 6. The Ciphertext E and the Authentication Tag T are returned as the 1095 outputs of the authenticated encryption. 1097 The encryption process can be illustrated as follows. Here K, P, A, 1098 IV, and E denote the key, plaintext, additional authenticated data, 1099 initialization vector, and ciphertext, respectively. 1101 MAC_KEY = initial MAC_KEY_LEN bytes of K, 1102 ENC_KEY = final ENC_KEY_LEN bytes of K, 1104 E = CBC-PKCS5-ENC(ENC_KEY, P), 1106 M = MAC(MAC_KEY, A || IV || E || AL), 1108 T = initial T_LEN bytes of M. 1110 5.2.2.2. AES_CBC_HMAC_SHA2 Decryption 1112 The authenticated decryption operation has four inputs: K, A, E, and 1113 T as defined above. It has only a single output, either a plaintext 1114 value P or a special symbol FAIL that indicates that the inputs are 1115 not authentic. The authenticated decryption algorithm is as follows, 1116 or uses an equivalent set of steps: 1118 1. The secondary keys MAC_KEY and ENC_KEY are generated from the 1119 input key K as in Step 1 of Section 5.2.2.1. 1121 2. The integrity and authenticity of A and E are checked by 1122 computing an HMAC with the inputs as in Step 5 of 1123 Section 5.2.2.1. The value T, from the previous step, is 1124 compared to the first MAC_KEY length bits of the HMAC output. If 1125 those values are identical, then A and E are considered valid, 1126 and processing is continued. Otherwise, all of the data used in 1127 the MAC validation are discarded, and the AEAD decryption 1128 operation returns an indication that it failed, and the operation 1129 halts. (But see Section 11 of [JWE] for security considerations 1130 on thwarting timing attacks.) 1132 3. The value E is decrypted and the PKCS #5 padding is removed. The 1133 value IV is used as the initialization vector. The value ENC_KEY 1134 is used as the decryption key. 1136 4. The plaintext value is returned. 1138 5.2.3. AES_128_CBC_HMAC_SHA_256 1140 This algorithm is a concrete instantiation of the generic 1141 AES_CBC_HMAC_SHA2 algorithm above. It uses the HMAC message 1142 authentication code [RFC2104] with the SHA-256 hash function [SHS] to 1143 provide message authentication, with the HMAC output truncated to 128 1144 bits, corresponding to the HMAC-SHA-256-128 algorithm defined in 1145 [RFC4868]. For encryption, it uses AES in the Cipher Block Chaining 1146 (CBC) mode of operation as defined in Section 6.2 of [NIST.800-38A], 1147 with PKCS #5 padding and a 128 bit initialization vector (IV) value. 1149 The AES_CBC_HMAC_SHA2 parameters specific to AES_128_CBC_HMAC_SHA_256 1150 are: 1152 The input key K is 32 octets long. 1154 ENC_KEY_LEN is 16 octets. 1156 MAC_KEY_LEN is 16 octets. 1158 The SHA-256 hash algorithm is used for the HMAC. 1160 The HMAC-SHA-256 output is truncated to T_LEN=16 octets, by 1161 stripping off the final 16 octets. 1163 5.2.4. AES_192_CBC_HMAC_SHA_384 1165 AES_192_CBC_HMAC_SHA_384 is based on AES_128_CBC_HMAC_SHA_256, but 1166 with the following differences: 1168 The input key K is 48 octets long instead of 32. 1170 ENC_KEY_LEN is 24 octets instead of 16. 1172 MAC_KEY_LEN is 24 octets instead of 16. 1174 SHA-384 is used for the HMAC instead of SHA-256. 1176 The HMAC SHA-384 value is truncated to T_LEN=24 octets instead of 1177 16. 1179 5.2.5. AES_256_CBC_HMAC_SHA_512 1181 AES_256_CBC_HMAC_SHA_512 is based on AES_128_CBC_HMAC_SHA_256, but 1182 with the following differences: 1184 The input key K is 64 octets long instead of 32. 1186 ENC_KEY_LEN is 32 octets instead of 16. 1188 MAC_KEY_LEN is 32 octets instead of 16. 1190 SHA-512 is used for the HMAC instead of SHA-256. 1192 The HMAC SHA-512 value is truncated to T_LEN=32 octets instead of 1193 16. 1195 5.2.6. Content Encryption with AES_CBC_HMAC_SHA2 1197 This section defines the specifics of performing authenticated 1198 encryption with the AES_CBC_HMAC_SHA2 algorithms. 1200 The CEK is used as the secret key K. 1202 The following "enc" (encryption algorithm) Header Parameter values 1203 are used to indicate that the JWE Ciphertext and JWE Authentication 1204 Tag values have been computed using the corresponding algorithm: 1206 +---------------+---------------------------------------------------+ 1207 | enc Parameter | Content Encryption Algorithm | 1208 | Value | | 1209 +---------------+---------------------------------------------------+ 1210 | A128CBC-HS256 | AES_128_CBC_HMAC_SHA_256 authenticated encryption | 1211 | | algorithm, as defined in Section 5.2.3 | 1212 | A192CBC-HS384 | AES_192_CBC_HMAC_SHA_384 authenticated encryption | 1213 | | algorithm, as defined in Section 5.2.4 | 1214 | A256CBC-HS512 | AES_256_CBC_HMAC_SHA_512 authenticated encryption | 1215 | | algorithm, as defined in Section 5.2.5 | 1216 +---------------+---------------------------------------------------+ 1218 5.3. Content Encryption with AES GCM 1220 This section defines the specifics of performing authenticated 1221 encryption with Advanced Encryption Standard (AES) in Galois/Counter 1222 Mode (GCM) [AES] [NIST.800-38D]. 1224 The CEK is used as the encryption key. 1226 Use of an initialization vector of size 96 bits is REQUIRED with this 1227 algorithm. 1229 The requested size of the Authentication Tag output MUST be 128 bits, 1230 regardless of the key size. 1232 The following "enc" (encryption algorithm) Header Parameter values 1233 are used to indicate that the JWE Ciphertext and JWE Authentication 1234 Tag values have been computed using the corresponding algorithm and 1235 key size: 1237 +---------------------+------------------------------+ 1238 | enc Parameter Value | Content Encryption Algorithm | 1239 +---------------------+------------------------------+ 1240 | A128GCM | AES GCM using 128 bit key | 1241 | A192GCM | AES GCM using 192 bit key | 1242 | A256GCM | AES GCM using 256 bit key | 1243 +---------------------+------------------------------+ 1245 An example using this algorithm is shown in Appendix A.1 of [JWE]. 1247 6. Cryptographic Algorithms for Keys 1249 A JSON Web Key (JWK) [JWK] is a JSON data structure that represents a 1250 cryptographic key. These keys can be either asymmetric or symmetric. 1251 They can hold both public and private information about the key. 1252 This section defines the parameters for keys using the algorithms 1253 specified by this document. 1255 6.1. "kty" (Key Type) Parameter Values 1257 The table below is the set of "kty" (key type) parameter values that 1258 are defined by this specification for use in JWKs. 1260 +--------------+--------------------------------+-------------------+ 1261 | kty | Key Type | Implementation | 1262 | Parameter | | Requirements | 1263 | Value | | | 1264 +--------------+--------------------------------+-------------------+ 1265 | EC | Elliptic Curve [DSS] | Recommended+ | 1266 | RSA | RSA [RFC3447] | Required | 1267 | oct | Octet sequence (used to | Required | 1268 | | represent symmetric keys) | | 1269 +--------------+--------------------------------+-------------------+ 1271 The use of "+" in the Implementation Requirements indicates that the 1272 requirement strength is likely to be increased in a future version of 1273 the specification. 1275 6.2. Parameters for Elliptic Curve Keys 1277 JWKs can represent Elliptic Curve [DSS] keys. In this case, the 1278 "kty" member value MUST be "EC". 1280 6.2.1. Parameters for Elliptic Curve Public Keys 1282 An elliptic curve public key is represented by a pair of coordinates 1283 drawn from a finite field, which together define a point on an 1284 elliptic curve. The following members MUST be present for elliptic 1285 curve public keys: 1287 o "crv" 1288 o "x" 1289 o "y" 1291 SEC1 [SEC1] point compression is not supported for any values. 1293 6.2.1.1. "crv" (Curve) Parameter 1295 The "crv" (curve) member identifies the cryptographic curve used with 1296 the key. Curve values from [DSS] used by this specification are: 1298 o "P-256" 1299 o "P-384" 1300 o "P-521" 1302 These values are registered in the IANA JSON Web Key Elliptic Curve 1303 registry defined in Section 7.6. Additional "crv" values MAY be 1304 used, provided they are understood by implementations using that 1305 Elliptic Curve key. The "crv" value is a case-sensitive string. 1307 6.2.1.2. "x" (X Coordinate) Parameter 1309 The "x" (x coordinate) member contains the x coordinate for the 1310 elliptic curve point. It is represented as the base64url encoding of 1311 the octet string representation of the coordinate, as defined in 1312 Section 2.3.5 of SEC1 [SEC1]. The length of this octet string MUST 1313 be the full size of a coordinate for the curve specified in the "crv" 1314 parameter. For example, if the value of "crv" is "P-521", the octet 1315 string must be 66 octets long. 1317 6.2.1.3. "y" (Y Coordinate) Parameter 1319 The "y" (y coordinate) member contains the y coordinate for the 1320 elliptic curve point. It is represented as the base64url encoding of 1321 the octet string representation of the coordinate, as defined in 1322 Section 2.3.5 of SEC1 [SEC1]. The length of this octet string MUST 1323 be the full size of a coordinate for the curve specified in the "crv" 1324 parameter. For example, if the value of "crv" is "P-521", the octet 1325 string must be 66 octets long. 1327 6.2.2. Parameters for Elliptic Curve Private Keys 1329 In addition to the members used to represent Elliptic Curve public 1330 keys, the following member MUST be present to represent Elliptic 1331 Curve private keys. 1333 6.2.2.1. "d" (ECC Private Key) Parameter 1335 The "d" (ECC private key) member contains the Elliptic Curve private 1336 key value. It is represented as the base64url encoding of the octet 1337 string representation of the private key value, as defined in 1338 Sections C.4 and 2.3.7 of SEC1 [SEC1]. The length of this octet 1339 string MUST be ceiling(log-base-2(n)/8) octets (where n is the order 1340 of the curve). 1342 6.3. Parameters for RSA Keys 1344 JWKs can represent RSA [RFC3447] keys. In this case, the "kty" 1345 member value MUST be "RSA". 1347 6.3.1. Parameters for RSA Public Keys 1349 The following members MUST be present for RSA public keys. 1351 6.3.1.1. "n" (Modulus) Parameter 1353 The "n" (modulus) member contains the modulus value for the RSA 1354 public key. It is represented as the base64url encoding of the 1355 value's unsigned big endian representation as an octet sequence. The 1356 octet sequence MUST utilize the minimum number of octets to represent 1357 the value. 1359 6.3.1.2. "e" (Exponent) Parameter 1361 The "e" (exponent) member contains the exponent value for the RSA 1362 public key. It is represented as the base64url encoding of the 1363 value's unsigned big endian representation as an octet sequence. The 1364 octet sequence MUST utilize the minimum number of octets to represent 1365 the value. For instance, when representing the value 65537, the 1366 octet sequence to be base64url encoded MUST consist of the three 1367 octets [1, 0, 1]. 1369 6.3.2. Parameters for RSA Private Keys 1371 In addition to the members used to represent RSA public keys, the 1372 following members are used to represent RSA private keys. The 1373 parameter "d" is REQUIRED for RSA private keys. The others enable 1374 optimizations and SHOULD be included by producers of JWKs 1375 representing RSA private keys. If the producer includes any of the 1376 other private key parameters, then all of the others MUST be present, 1377 with the exception of "oth", which MUST only be present when more 1378 than two prime factors were used. The consumer of a JWK MAY choose 1379 to accept an RSA private key that does not contain a complete set of 1380 the private key parameters other than "d", including JWKs in which 1381 "d" is the only RSA private key parameter included. 1383 6.3.2.1. "d" (Private Exponent) Parameter 1385 The "d" (private exponent) member contains the private exponent value 1386 for the RSA private key. It is represented as the base64url encoding 1387 of the value's unsigned big endian representation as an octet 1388 sequence. The octet sequence MUST utilize the minimum number of 1389 octets to represent the value. 1391 6.3.2.2. "p" (First Prime Factor) Parameter 1393 The "p" (first prime factor) member contains the first prime factor, 1394 a positive integer. It is represented as the base64url encoding of 1395 the value's unsigned big endian representation as an octet sequence. 1396 The octet sequence MUST utilize the minimum number of octets to 1397 represent the value. 1399 6.3.2.3. "q" (Second Prime Factor) Parameter 1401 The "q" (second prime factor) member contains the second prime 1402 factor, a positive integer. It is represented as the base64url 1403 encoding of the value's unsigned big endian representation as an 1404 octet sequence. The octet sequence MUST utilize the minimum number 1405 of octets to represent the value. 1407 6.3.2.4. "dp" (First Factor CRT Exponent) Parameter 1409 The "dp" (first factor CRT exponent) member contains the Chinese 1410 Remainder Theorem (CRT) exponent of the first factor, a positive 1411 integer. It is represented as the base64url encoding of the value's 1412 unsigned big endian representation as an octet sequence. The octet 1413 sequence MUST utilize the minimum number of octets to represent the 1414 value. 1416 6.3.2.5. "dq" (Second Factor CRT Exponent) Parameter 1418 The "dq" (second factor CRT exponent) member contains the Chinese 1419 Remainder Theorem (CRT) exponent of the second factor, a positive 1420 integer. It is represented as the base64url encoding of the value's 1421 unsigned big endian representation as an octet sequence. The octet 1422 sequence MUST utilize the minimum number of octets to represent the 1423 value. 1425 6.3.2.6. "qi" (First CRT Coefficient) Parameter 1427 The "dp" (first CRT coefficient) member contains the Chinese 1428 Remainder Theorem (CRT) coefficient of the second factor, a positive 1429 integer. It is represented as the base64url encoding of the value's 1430 unsigned big endian representation as an octet sequence. The octet 1431 sequence MUST utilize the minimum number of octets to represent the 1432 value. 1434 6.3.2.7. "oth" (Other Primes Info) Parameter 1436 The "oth" (other primes info) member contains an array of information 1437 about any third and subsequent primes, should they exist. When only 1438 two primes have been used (the normal case), this parameter MUST be 1439 omitted. When three or more primes have been used, the number of 1440 array elements MUST be the number of primes used minus two. Each 1441 array element MUST be an object with the following members: 1443 6.3.2.7.1. "r" (Prime Factor) 1445 The "r" (prime factor) parameter within an "oth" array member 1446 represents the value of a subsequent prime factor, a positive 1447 integer. It is represented as the base64url encoding of the value's 1448 unsigned big endian representation as an octet sequence. The octet 1449 sequence MUST utilize the minimum number of octets to represent the 1450 value. 1452 6.3.2.7.2. "d" (Factor CRT Exponent) 1454 The "d" (Factor CRT Exponent) parameter within an "oth" array member 1455 represents the CRT exponent of the corresponding prime factor, a 1456 positive integer. It is represented as the base64url encoding of the 1457 value's unsigned big endian representation as an octet sequence. The 1458 octet sequence MUST utilize the minimum number of octets to represent 1459 the value. 1461 6.3.2.7.3. "t" (Factor CRT Coefficient) 1463 The "t" (factor CRT coefficient) parameter within an "oth" array 1464 member represents the CRT coefficient of the corresponding prime 1465 factor, a positive integer. It is represented as the base64url 1466 encoding of the value's unsigned big endian representation as an 1467 octet sequence. The octet sequence MUST utilize the minimum number 1468 of octets to represent the value. 1470 6.4. Parameters for Symmetric Keys 1472 When the JWK "kty" member value is "oct" (octet sequence), the member 1473 "k" is used to represent a symmetric key (or another key whose value 1474 is a single octet sequence). An "alg" member SHOULD also be present 1475 to identify the algorithm intended to be used with the key, unless 1476 the application uses another means or convention to determine the 1477 algorithm used. 1479 6.4.1. "k" (Key Value) Parameter 1481 The "k" (key value) member contains the value of the symmetric (or 1482 other single-valued) key. It is represented as the base64url 1483 encoding of the octet sequence containing the key value. 1485 7. IANA Considerations 1487 The following registration procedure is used for all the registries 1488 established by this specification. 1490 Values are registered with a Specification Required [RFC5226] after a 1491 two-week review period on the [TBD]@ietf.org mailing list, on the 1492 advice of one or more Designated Experts. However, to allow for the 1493 allocation of values prior to publication, the Designated Expert(s) 1494 may approve registration once they are satisfied that such a 1495 specification will be published. 1497 Registration requests must be sent to the [TBD]@ietf.org mailing list 1498 for review and comment, with an appropriate subject (e.g., "Request 1499 for access token type: example"). [[ Note to the RFC Editor: The name 1500 of the mailing list should be determined in consultation with the 1501 IESG and IANA. Suggested name: jose-reg-review. ]] 1503 Within the review period, the Designated Expert(s) will either 1504 approve or deny the registration request, communicating this decision 1505 to the review list and IANA. Denials should include an explanation 1506 and, if applicable, suggestions as to how to make the request 1507 successful. Registration requests that are undetermined for a period 1508 longer than 21 days can be brought to the IESG's attention (using the 1509 iesg@iesg.org mailing list) for resolution. 1511 Criteria that should be applied by the Designated Expert(s) includes 1512 determining whether the proposed registration duplicates existing 1513 functionality, determining whether it is likely to be of general 1514 applicability or whether it is useful only for a single application, 1515 and whether the registration makes sense. 1517 IANA must only accept registry updates from the Designated Expert(s) 1518 and should direct all requests for registration to the review mailing 1519 list. 1521 It is suggested that multiple Designated Experts be appointed who are 1522 able to represent the perspectives of different applications using 1523 this specification, in order to enable broadly-informed review of 1524 registration decisions. In cases where a registration decision could 1525 be perceived as creating a conflict of interest for a particular 1526 Expert, that Expert should defer to the judgment of the other 1527 Expert(s). 1529 7.1. JSON Web Signature and Encryption Algorithms Registry 1531 This specification establishes the IANA JSON Web Signature and 1532 Encryption Algorithms registry for values of the JWS and JWE "alg" 1533 (algorithm) and "enc" (encryption algorithm) Header Parameters. The 1534 registry records the algorithm name, the algorithm usage locations, 1535 implementation requirements, and a reference to the specification 1536 that defines it. The same algorithm name can be registered multiple 1537 times, provided that the sets of usage locations are disjoint. 1539 It is suggested that when algorithms can use keys of different 1540 lengths, that the length of the key be included in the algorithm 1541 name. This allows readers of the JSON text to easily make security 1542 consideration decisions. 1544 The implementation requirements of an algorithm MAY be changed over 1545 time by the Designated Experts(s) as the cryptographic landscape 1546 evolves, for instance, to change the status of an algorithm to 1547 Deprecated, or to change the status of an algorithm from Optional to 1548 Recommended+ or Required. Changes of implementation requirements are 1549 only permitted on a Specification Required basis, with the new 1550 specification defining the revised implementation requirements level. 1552 7.1.1. Registration Template 1554 Algorithm Name: 1555 The name requested (e.g., "example"). This name is case- 1556 sensitive. Names may not match other registered names in a case- 1557 insensitive manner unless the Designated Expert(s) state that 1558 there is a compelling reason to allow an exception in this 1559 particular case. 1561 Algorithm Description: 1562 Brief description of the Algorithm (e.g., "Example description"). 1564 Algorithm Usage Location(s): 1565 The algorithm usage location. This must be one or more of the 1566 values "alg" or "enc" if the algorithm is to be used with JWS or 1567 JWE. The value "JWK" is used if the algorithm identifier will be 1568 used as a JWK "alg" member value, but will not be used with JWS or 1569 JWE; this could be the case, for instance, for non-authenticated 1570 encryption algorithms. Other values may be used with the approval 1571 of a Designated Expert. 1573 JOSE Implementation Requirements: 1574 The algorithm implementation requirements for JWS and JWE, which 1575 must be one the words Required, Recommended, Optional, Deprecated, 1576 or Prohibited. Optionally, the word can be followed by a "+" or 1577 "-". The use of "+" indicates that the requirement strength is 1578 likely to be increased in a future version of the specification. 1579 The use of "-" indicates that the requirement strength is likely 1580 to be decreased in a future version of the specification. Any 1581 identifiers registered for non-authenticated encryption algorithms 1582 or other algorithms that are otherwise unsuitable for direct use 1583 as JWS or JWE algorithms must be registered as "Prohibited". 1585 Change Controller: 1586 For Standards Track RFCs, state "IESG". For others, give the name 1587 of the responsible party. Other details (e.g., postal address, 1588 email address, home page URI) may also be included. 1590 Specification Document(s): 1591 Reference to the document(s) that specify the parameter, 1592 preferably including URI(s) that can be used to retrieve copies of 1593 the document(s). An indication of the relevant sections may also 1594 be included but is not required. 1596 7.1.2. Initial Registry Contents 1598 o Algorithm Name: "HS256" 1599 o Algorithm Description: HMAC using SHA-256 1600 o Algorithm Usage Location(s): "alg" 1601 o JOSE Implementation Requirements: Required 1602 o Change Controller: IESG 1603 o Specification Document(s): Section 3.1 of [[ this document ]] 1605 o Algorithm Name: "HS384" 1606 o Algorithm Description: HMAC using SHA-384 1607 o Algorithm Usage Location(s): "alg" 1608 o JOSE Implementation Requirements: Optional 1609 o Change Controller: IESG 1610 o Specification Document(s): Section 3.1 of [[ this document ]] 1612 o Algorithm Name: "HS512" 1613 o Algorithm Description: HMAC using SHA-512 1614 o Algorithm Usage Location(s): "alg" 1615 o JOSE Implementation Requirements: Optional 1616 o Change Controller: IESG 1617 o Specification Document(s): Section 3.1 of [[ this document ]] 1618 o Algorithm Name: "RS256" 1619 o Algorithm Description: RSASSA-PKCS-v1_5 using SHA-256 1620 o Algorithm Usage Location(s): "alg" 1621 o JOSE Implementation Requirements: Recommended 1622 o Change Controller: IESG 1623 o Specification Document(s): Section 3.1 of [[ this document ]] 1625 o Algorithm Name: "RS384" 1626 o Algorithm Description: RSASSA-PKCS-v1_5 using SHA-384 1627 o Algorithm Usage Location(s): "alg" 1628 o JOSE Implementation Requirements: Optional 1629 o Change Controller: IESG 1630 o Specification Document(s): Section 3.1 of [[ this document ]] 1632 o Algorithm Name: "RS512" 1633 o Algorithm Description: RSASSA-PKCS-v1_5 using SHA-512 1634 o Algorithm Usage Location(s): "alg" 1635 o JOSE Implementation Requirements: Optional 1636 o Change Controller: IESG 1637 o Specification Document(s): Section 3.1 of [[ this document ]] 1639 o Algorithm Name: "ES256" 1640 o Algorithm Description: ECDSA using P-256 and SHA-256 1641 o Algorithm Usage Location(s): "alg" 1642 o JOSE Implementation Requirements: Recommended+ 1643 o Change Controller: IESG 1644 o Specification Document(s): Section 3.1 of [[ this document ]] 1646 o Algorithm Name: "ES384" 1647 o Algorithm Description: ECDSA using P-384 and SHA-384 1648 o Algorithm Usage Location(s): "alg" 1649 o JOSE Implementation Requirements: Optional 1650 o Change Controller: IESG 1651 o Specification Document(s): Section 3.1 of [[ this document ]] 1653 o Algorithm Name: "ES512" 1654 o Algorithm Description: ECDSA using P-521 and SHA-512 1655 o Algorithm Usage Location(s): "alg" 1656 o JOSE Implementation Requirements: Optional 1657 o Change Controller: IESG 1658 o Specification Document(s): Section 3.1 of [[ this document ]] 1660 o Algorithm Name: "PS256" 1661 o Algorithm Description: RSASSA-PSS using SHA-256 and MGF1 with SHA- 1662 256 1663 o Algorithm Usage Location(s): "alg" 1664 o JOSE Implementation Requirements: Optional 1665 o Change Controller: IESG 1666 o Specification Document(s): Section 3.1 of [[ this document ]] 1668 o Algorithm Name: "PS384" 1669 o Algorithm Description: RSASSA-PSS using SHA-384 and MGF1 with SHA- 1670 384 1671 o Algorithm Usage Location(s): "alg" 1672 o JOSE Implementation Requirements: Optional 1673 o Change Controller: IESG 1674 o Specification Document(s): Section 3.1 of [[ this document ]] 1676 o Algorithm Name: "PS512" 1677 o Algorithm Description: RSASSA-PSS using SHA-512 and MGF1 with SHA- 1678 512 1679 o Algorithm Usage Location(s): "alg" 1680 o JOSE Implementation Requirements: Optional 1681 o Change Controller: IESG 1682 o Specification Document(s): Section 3.1 of [[ this document ]] 1684 o Algorithm Name: "none" 1685 o Algorithm Description: No digital signature or MAC performed 1686 o Algorithm Usage Location(s): "alg" 1687 o JOSE Implementation Requirements: Optional 1688 o Change Controller: IESG 1689 o Specification Document(s): Section 3.1 of [[ this document ]] 1691 o Algorithm Name: "RSA1_5" 1692 o Algorithm Description: RSAES-PKCS1-V1_5 1693 o Algorithm Usage Location(s): "alg" 1694 o JOSE Implementation Requirements: Required 1695 o Change Controller: IESG 1696 o Specification Document(s): Section 4.1 of [[ this document ]] 1698 o Algorithm Name: "RSA-OAEP" 1699 o Algorithm Description: RSAES OAEP using default parameters 1700 o Algorithm Usage Location(s): "alg" 1701 o JOSE Implementation Requirements: Optional 1702 o Change Controller: IESG 1703 o Specification Document(s): Section 4.1 of [[ this document ]] 1705 o Algorithm Name: "RSA-OAEP-256" 1706 o Algorithm Description: RSAES OAEP using SHA-256 and MGF1 with SHA- 1707 256 1708 o Algorithm Usage Location(s): "alg" 1709 o JOSE Implementation Requirements: Optional 1710 o Change Controller: IESG 1711 o Specification Document(s): Section 4.1 of [[ this document ]] 1713 o Algorithm Name: "A128KW" 1714 o Algorithm Description: AES Key Wrap using 128 bit key 1715 o Algorithm Usage Location(s): "alg" 1716 o JOSE Implementation Requirements: Recommended 1717 o Change Controller: IESG 1718 o Specification Document(s): Section 4.1 of [[ this document ]] 1720 o Algorithm Name: "A192KW" 1721 o Algorithm Description: AES Key Wrap using 192 bit key 1722 o Algorithm Usage Location(s): "alg" 1723 o JOSE Implementation Requirements: Optional 1724 o Change Controller: IESG 1725 o Specification Document(s): Section 4.1 of [[ this document ]] 1727 o Algorithm Name: "A256KW" 1728 o Algorithm Description: AES Key Wrap using 256 bit key 1729 o Algorithm Usage Location(s): "alg" 1730 o JOSE Implementation Requirements: Recommended 1731 o Change Controller: IESG 1732 o Specification Document(s): Section 4.1 of [[ this document ]] 1734 o Algorithm Name: "dir" 1735 o Algorithm Description: Direct use of a shared symmetric key 1736 o Algorithm Usage Location(s): "alg" 1737 o JOSE Implementation Requirements: Recommended 1738 o Change Controller: IESG 1739 o Specification Document(s): Section 4.1 of [[ this document ]] 1741 o Algorithm Name: "ECDH-ES" 1742 o Algorithm Description: ECDH-ES using Concat KDF 1743 o Algorithm Usage Location(s): "alg" 1744 o JOSE Implementation Requirements: Recommended+ 1745 o Change Controller: IESG 1746 o Specification Document(s): Section 4.1 of [[ this document ]] 1748 o Algorithm Name: "ECDH-ES+A128KW" 1749 o Algorithm Description: ECDH-ES using Concat KDF and "A128KW" 1750 wrapping 1751 o Algorithm Usage Location(s): "alg" 1752 o JOSE Implementation Requirements: Recommended 1753 o Change Controller: IESG 1754 o Specification Document(s): Section 4.1 of [[ this document ]] 1755 o Algorithm Name: "ECDH-ES+A192KW" 1756 o Algorithm Description: ECDH-ES using Concat KDF and "A192KW" 1757 wrapping 1758 o Algorithm Usage Location(s): "alg" 1759 o JOSE Implementation Requirements: Optional 1760 o Change Controller: IESG 1761 o Specification Document(s): Section 4.1 of [[ this document ]] 1763 o Algorithm Name: "ECDH-ES+A256KW" 1764 o Algorithm Description: ECDH-ES using Concat KDF and "A256KW" 1765 wrapping 1766 o Algorithm Usage Location(s): "alg" 1767 o JOSE Implementation Requirements: Recommended 1768 o Change Controller: IESG 1769 o Specification Document(s): Section 4.1 of [[ this document ]] 1771 o Algorithm Name: "A128GCMKW" 1772 o Algorithm Description: Key wrapping with AES GCM using 128 bit key 1773 o Algorithm Usage Location(s): "alg" 1774 o JOSE Implementation Requirements: Optional 1775 o Change Controller: IESG 1776 o Specification Document(s): Section 4.7 of [[ this document ]] 1778 o Algorithm Name: "A192GCMKW" 1779 o Algorithm Description: Key wrapping with AES GCM using 192 bit key 1780 o Algorithm Usage Location(s): "alg" 1781 o JOSE Implementation Requirements: Optional 1782 o Change Controller: IESG 1783 o Specification Document(s): Section 4.7 of [[ this document ]] 1785 o Algorithm Name: "A256GCMKW" 1786 o Algorithm Description: Key wrapping with AES GCM using 256 bit key 1787 o Algorithm Usage Location(s): "alg" 1788 o JOSE Implementation Requirements: Optional 1789 o Change Controller: IESG 1790 o Specification Document(s): Section 4.7 of [[ this document ]] 1792 o Algorithm Name: "PBES2-HS256+A128KW" 1793 o Algorithm Description: PBES2 with HMAC SHA-256 and "A128KW" 1794 wrapping 1795 o Algorithm Usage Location(s): "alg" 1796 o JOSE Implementation Requirements: Optional 1797 o Change Controller: IESG 1798 o Specification Document(s): Section 4.8 of [[ this document ]] 1800 o Algorithm Name: "PBES2-HS384+A192KW" 1801 o Algorithm Description: PBES2 with HMAC SHA-384 and "A192KW" 1802 wrapping 1803 o Algorithm Usage Location(s): "alg" 1804 o JOSE Implementation Requirements: Optional 1805 o Change Controller: IESG 1806 o Specification Document(s): Section 4.8 of [[ this document ]] 1808 o Algorithm Name: "PBES2-HS512+A256KW" 1809 o Algorithm Description: PBES2 with HMAC SHA-512 and "A256KW" 1810 wrapping 1811 o Algorithm Usage Location(s): "alg" 1812 o JOSE Implementation Requirements: Optional 1813 o Change Controller: IESG 1814 o Specification Document(s): Section 4.8 of [[ this document ]] 1816 o Algorithm Name: "A128CBC-HS256" 1817 o Algorithm Description: AES_128_CBC_HMAC_SHA_256 authenticated 1818 encryption algorithm 1819 o Algorithm Usage Location(s): "enc" 1820 o JOSE Implementation Requirements: Required 1821 o Change Controller: IESG 1822 o Specification Document(s): Section 5.1 of [[ this document ]] 1824 o Algorithm Name: "A192CBC-HS384" 1825 o Algorithm Description: AES_192_CBC_HMAC_SHA_384 authenticated 1826 encryption algorithm 1827 o Algorithm Usage Location(s): "enc" 1828 o JOSE Implementation Requirements: Optional 1829 o Change Controller: IESG 1830 o Specification Document(s): Section 5.1 of [[ this document ]] 1832 o Algorithm Name: "A256CBC-HS512" 1833 o Algorithm Description: AES_256_CBC_HMAC_SHA_512 authenticated 1834 encryption algorithm 1835 o Algorithm Usage Location(s): "enc" 1836 o JOSE Implementation Requirements: Required 1837 o Change Controller: IESG 1838 o Specification Document(s): Section 5.1 of [[ this document ]] 1840 o Algorithm Name: "A128GCM" 1841 o Algorithm Description: AES GCM using 128 bit key 1842 o Algorithm Usage Location(s): "enc" 1843 o JOSE Implementation Requirements: Recommended 1844 o Change Controller: IESG 1845 o Specification Document(s): Section 5.1 of [[ this document ]] 1846 o Algorithm Name: "A192GCM" 1847 o Algorithm Description: AES GCM using 192 bit key 1848 o Algorithm Usage Location(s): "enc" 1849 o JOSE Implementation Requirements: Optional 1850 o Change Controller: IESG 1851 o Specification Document(s): Section 5.1 of [[ this document ]] 1853 o Algorithm Name: "A256GCM" 1854 o Algorithm Description: AES GCM using 256 bit key 1855 o Algorithm Usage Location(s): "enc" 1856 o JOSE Implementation Requirements: Recommended 1857 o Change Controller: IESG 1858 o Specification Document(s): Section 5.1 of [[ this document ]] 1860 7.2. JWE Header Parameter Names Registration 1862 This specification registers the Header Parameter names defined in 1863 Section 4.6.1, Section 4.7.1, and Section 4.8.1 in the IANA JSON Web 1864 Signature and Encryption Header Parameters registry defined in [JWS]. 1866 7.2.1. Registry Contents 1868 o Header Parameter Name: "epk" 1869 o Header Parameter Description: Ephemeral Public Key 1870 o Header Parameter Usage Location(s): JWE 1871 o Change Controller: IESG 1872 o Specification Document(s): Section 4.6.1.1 of [[ this document ]] 1874 o Header Parameter Name: "apu" 1875 o Header Parameter Description: Agreement PartyUInfo 1876 o Header Parameter Usage Location(s): JWE 1877 o Change Controller: IESG 1878 o Specification Document(s): Section 4.6.1.2 of [[ this document ]] 1880 o Header Parameter Name: "apv" 1881 o Header Parameter Description: Agreement PartyVInfo 1882 o Header Parameter Usage Location(s): JWE 1883 o Change Controller: IESG 1884 o Specification Document(s): Section 4.6.1.3 of [[ this document ]] 1886 o Header Parameter Name: "iv" 1887 o Header Parameter Description: Initialization Vector 1888 o Header Parameter Usage Location(s): JWE 1889 o Change Controller: IESG 1890 o Specification Document(s): Section 4.7.1.1 of [[ this document ]] 1891 o Header Parameter Name: "tag" 1892 o Header Parameter Description: Authentication Tag 1893 o Header Parameter Usage Location(s): JWE 1894 o Change Controller: IESG 1895 o Specification Document(s): Section 4.7.1.2 of [[ this document ]] 1897 o Header Parameter Name: "p2s" 1898 o Header Parameter Description: PBES2 salt 1899 o Header Parameter Usage Location(s): JWE 1900 o Change Controller: IESG 1901 o Specification Document(s): Section 4.8.1.1 of [[ this document ]] 1903 o Header Parameter Name: "p2c" 1904 o Header Parameter Description: PBES2 count 1905 o Header Parameter Usage Location(s): JWE 1906 o Change Controller: IESG 1907 o Specification Document(s): Section 4.8.1.2 of [[ this document ]] 1909 7.3. JSON Web Encryption Compression Algorithms Registry 1911 This specification establishes the IANA JSON Web Encryption 1912 Compression Algorithms registry for JWE "zip" member values. The 1913 registry records the compression algorithm value and a reference to 1914 the specification that defines it. 1916 7.3.1. Registration Template 1918 Compression Algorithm Value: 1919 The name requested (e.g., "example"). Because a core goal of this 1920 specification is for the resulting representations to be compact, 1921 it is RECOMMENDED that the name be short -- not to exceed 8 1922 characters without a compelling reason to do so. This name is 1923 case-sensitive. Names may not match other registered names in a 1924 case-insensitive manner unless the Designated Expert(s) state that 1925 there is a compelling reason to allow an exception in this 1926 particular case. 1928 Compression Algorithm Description: 1929 Brief description of the compression algorithm (e.g., "Example 1930 description"). 1932 Change Controller: 1933 For Standards Track RFCs, state "IESG". For others, give the name 1934 of the responsible party. Other details (e.g., postal address, 1935 email address, home page URI) may also be included. 1937 Specification Document(s): 1938 Reference to the document(s) that specify the parameter, 1939 preferably including URI(s) that can be used to retrieve copies of 1940 the document(s). An indication of the relevant sections may also 1941 be included but is not required. 1943 7.3.2. Initial Registry Contents 1945 o Compression Algorithm Value: "DEF" 1946 o Compression Algorithm Description: DEFLATE 1947 o Change Controller: IESG 1948 o Specification Document(s): JSON Web Encryption (JWE) [JWE] 1950 7.4. JSON Web Key Types Registry 1952 This specification establishes the IANA JSON Web Key Types registry 1953 for values of the JWK "kty" (key type) parameter. The registry 1954 records the "kty" value, implementation requirements, and a reference 1955 to the specification that defines it. 1957 The implementation requirements of a key type MAY be changed over 1958 time by the Designated Experts(s) as the cryptographic landscape 1959 evolves, for instance, to change the status of a key type to 1960 Deprecated, or to change the status of a key type from Optional to 1961 Recommended+ or Required. Changes of implementation requirements are 1962 only permitted on a Specification Required basis, with the new 1963 specification defining the revised implementation requirements level. 1965 7.4.1. Registration Template 1967 "kty" Parameter Value: 1968 The name requested (e.g., "example"). Because a core goal of this 1969 specification is for the resulting representations to be compact, 1970 it is RECOMMENDED that the name be short -- not to exceed 8 1971 characters without a compelling reason to do so. This name is 1972 case-sensitive. Names may not match other registered names in a 1973 case-insensitive manner unless the Designated Expert(s) state that 1974 there is a compelling reason to allow an exception in this 1975 particular case. 1977 Key Type Description: 1978 Brief description of the Key Type (e.g., "Example description"). 1980 Change Controller: 1981 For Standards Track RFCs, state "IESG". For others, give the name 1982 of the responsible party. Other details (e.g., postal address, 1983 email address, home page URI) may also be included. 1985 JOSE Implementation Requirements: 1986 The key type implementation requirements for JWS and JWE, which 1987 must be one the words Required, Recommended, Optional, Deprecated, 1988 or Prohibited. Optionally, the word can be followed by a "+" or 1989 "-". The use of "+" indicates that the requirement strength is 1990 likely to be increased in a future version of the specification. 1991 The use of "-" indicates that the requirement strength is likely 1992 to be decreased in a future version of the specification. 1994 Specification Document(s): 1995 Reference to the document(s) that specify the parameter, 1996 preferably including URI(s) that can be used to retrieve copies of 1997 the document(s). An indication of the relevant sections may also 1998 be included but is not required. 2000 7.4.2. Initial Registry Contents 2002 This specification registers the values defined in Section 6.1. 2004 o "kty" Parameter Value: "EC" 2005 o Key Type Description: Elliptic Curve 2006 o JOSE Implementation Requirements: Recommended+ 2007 o Change Controller: IESG 2008 o Specification Document(s): Section 6.2 of [[ this document ]] 2010 o "kty" Parameter Value: "RSA" 2011 o Key Type Description: RSA 2012 o JOSE Implementation Requirements: Required 2013 o Change Controller: IESG 2014 o Specification Document(s): Section 6.3 of [[ this document ]] 2016 o "kty" Parameter Value: "oct" 2017 o Key Type Description: Octet sequence 2018 o JOSE Implementation Requirements: Required 2019 o Change Controller: IESG 2020 o Specification Document(s): Section 6.4 of [[ this document ]] 2022 7.5. JSON Web Key Parameters Registration 2024 This specification registers the parameter names defined in Sections 2025 6.2, 6.3, and 6.4 in the IANA JSON Web Key Parameters registry 2026 defined in [JWK]. 2028 7.5.1. Registry Contents 2030 o Parameter Name: "crv" 2031 o Parameter Description: Curve 2032 o Used with "kty" Value(s): "EC" 2033 o Parameter Information Class: Public 2034 o Change Controller: IESG 2035 o Specification Document(s): Section 6.2.1.1 of [[ this document ]] 2037 o Parameter Name: "x" 2038 o Parameter Description: X Coordinate 2039 o Used with "kty" Value(s): "EC" 2040 o Parameter Information Class: Public 2041 o Change Controller: IESG 2042 o Specification Document(s): Section 6.2.1.2 of [[ this document ]] 2044 o Parameter Name: "y" 2045 o Parameter Description: Y Coordinate 2046 o Used with "kty" Value(s): "EC" 2047 o Parameter Information Class: Public 2048 o Change Controller: IESG 2049 o Specification Document(s): Section 6.2.1.3 of [[ this document ]] 2051 o Parameter Name: "d" 2052 o Parameter Description: ECC Private Key 2053 o Used with "kty" Value(s): "EC" 2054 o Parameter Information Class: Private 2055 o Change Controller: IESG 2056 o Specification Document(s): Section 6.2.2.1 of [[ this document ]] 2058 o Parameter Name: "n" 2059 o Parameter Description: Modulus 2060 o Used with "kty" Value(s): "RSA" 2061 o Parameter Information Class: Public 2062 o Change Controller: IESG 2063 o Specification Document(s): Section 6.3.1.1 of [[ this document ]] 2065 o Parameter Name: "e" 2066 o Parameter Description: Exponent 2067 o Used with "kty" Value(s): "RSA" 2068 o Parameter Information Class: Public 2069 o Change Controller: IESG 2070 o Specification Document(s): Section 6.3.1.2 of [[ this document ]] 2072 o Parameter Name: "d" 2073 o Parameter Description: Private Exponent 2074 o Used with "kty" Value(s): "RSA" 2075 o Parameter Information Class: Private 2076 o Change Controller: IESG 2077 o Specification Document(s): Section 6.3.2.1 of [[ this document ]] 2079 o Parameter Name: "p" 2080 o Parameter Description: First Prime Factor 2081 o Used with "kty" Value(s): "RSA" 2082 o Parameter Information Class: Private 2083 o Change Controller: IESG 2084 o Specification Document(s): Section 6.3.2.2 of [[ this document ]] 2086 o Parameter Name: "q" 2087 o Parameter Description: Second Prime Factor 2088 o Used with "kty" Value(s): "RSA" 2089 o Parameter Information Class: Private 2090 o Change Controller: IESG 2091 o Specification Document(s): Section 6.3.2.3 of [[ this document ]] 2093 o Parameter Name: "dp" 2094 o Parameter Description: First Factor CRT Exponent 2095 o Used with "kty" Value(s): "RSA" 2096 o Parameter Information Class: Private 2097 o Change Controller: IESG 2098 o Specification Document(s): Section 6.3.2.4 of [[ this document ]] 2100 o Parameter Name: "dq" 2101 o Parameter Description: Second Factor CRT Exponent 2102 o Used with "kty" Value(s): "RSA" 2103 o Parameter Information Class: Private 2104 o Change Controller: IESG 2105 o Specification Document(s): Section 6.3.2.5 of [[ this document ]] 2107 o Parameter Name: "qi" 2108 o Parameter Description: First CRT Coefficient 2109 o Used with "kty" Value(s): "RSA" 2110 o Parameter Information Class: Private 2111 o Change Controller: IESG 2112 o Specification Document(s): Section 6.3.2.6 of [[ this document ]] 2114 o Parameter Name: "oth" 2115 o Parameter Description: Other Primes Info 2116 o Used with "kty" Value(s): "RSA" 2117 o Parameter Information Class: Private 2118 o Change Controller: IESG 2119 o Specification Document(s): Section 6.3.2.7 of [[ this document ]] 2121 o Parameter Name: "k" 2122 o Parameter Description: Key Value 2123 o Used with "kty" Value(s): "oct" 2124 o Parameter Information Class: Private 2125 o Change Controller: IESG 2126 o Specification Document(s): Section 6.4.1 of [[ this document ]] 2128 7.6. JSON Web Key Elliptic Curve Registry 2130 This specification establishes the IANA JSON Web Key Elliptic Curve 2131 registry for JWK "crv" member values. The registry records the curve 2132 name, implementation requirements, and a reference to the 2133 specification that defines it. This specification registers the 2134 parameter names defined in Section 6.2.1.1. 2136 The implementation requirements of a curve MAY be changed over time 2137 by the Designated Experts(s) as the cryptographic landscape evolves, 2138 for instance, to change the status of a curve to Deprecated, or to 2139 change the status of a curve from Optional to Recommended+ or 2140 Required. Changes of implementation requirements are only permitted 2141 on a Specification Required basis, with the new specification 2142 defining the revised implementation requirements level. 2144 7.6.1. Registration Template 2146 Curve Name: 2147 The name requested (e.g., "example"). Because a core goal of this 2148 specification is for the resulting representations to be compact, 2149 it is RECOMMENDED that the name be short -- not to exceed 8 2150 characters without a compelling reason to do so. This name is 2151 case-sensitive. Names may not match other registered names in a 2152 case-insensitive manner unless the Designated Expert(s) state that 2153 there is a compelling reason to allow an exception in this 2154 particular case. 2156 Curve Description: 2157 Brief description of the curve (e.g., "Example description"). 2159 JOSE Implementation Requirements: 2160 The curve implementation requirements for JWS and JWE, which must 2161 be one the words Required, Recommended, Optional, Deprecated, or 2162 Prohibited. Optionally, the word can be followed by a "+" or "-". 2163 The use of "+" indicates that the requirement strength is likely 2164 to be increased in a future version of the specification. The use 2165 of "-" indicates that the requirement strength is likely to be 2166 decreased in a future version of the specification. 2168 Change Controller: 2169 For Standards Track RFCs, state "IESG". For others, give the name 2170 of the responsible party. Other details (e.g., postal address, 2171 email address, home page URI) may also be included. 2173 Specification Document(s): 2174 Reference to the document(s) that specify the parameter, 2175 preferably including URI(s) that can be used to retrieve copies of 2176 the document(s). An indication of the relevant sections may also 2177 be included but is not required. 2179 7.6.2. Initial Registry Contents 2181 o Curve Name: "P-256" 2182 o Curve Description: P-256 curve 2183 o JOSE Implementation Requirements: Recommended+ 2184 o Change Controller: IESG 2185 o Specification Document(s): Section 6.2.1.1 of [[ this document ]] 2187 o Curve Name: "P-384" 2188 o Curve Description: P-384 curve 2189 o JOSE Implementation Requirements: Optional 2190 o Change Controller: IESG 2191 o Specification Document(s): Section 6.2.1.1 of [[ this document ]] 2193 o Curve Name: "P-521" 2194 o Curve Description: P-521 curve 2195 o JOSE Implementation Requirements: Optional 2196 o Change Controller: IESG 2197 o Specification Document(s): Section 6.2.1.1 of [[ this document ]] 2199 8. Security Considerations 2201 All of the security issues faced by any cryptographic application 2202 must be faced by a JWS/JWE/JWK agent. Among these issues are 2203 protecting the user's private and symmetric keys, preventing various 2204 attacks, and helping the user avoid mistakes such as inadvertently 2205 encrypting a message for the wrong recipient. The entire list of 2206 security considerations is beyond the scope of this document, but 2207 some significant considerations are listed here. 2209 The security considerations in [AES], [DSS], [JWE], [JWK], [JWS], 2210 [NIST.800-38A], [NIST.800-38D], [NIST.800-56A], [RFC2104], [RFC3394], 2211 [RFC3447], [RFC5116], [RFC6090], and [SHS] apply to this 2212 specification. 2214 Algorithms of matching strengths should be used together whenever 2215 possible. For instance, when AES Key Wrap is used with a given key 2216 size, using the same key size is recommended when AES GCM is also 2217 used. 2219 8.1. Algorithms and Key Sizes will be Deprecated 2221 Eventually the algorithms and/or key sizes currently described in 2222 this specification will no longer be considered sufficiently secure 2223 and will be deprecated. Therefore, implementers and deployments must 2224 be prepared for this eventuality. 2226 8.2. Key Lifetimes 2228 Many algorithms have associated security considerations related to 2229 key lifetimes and/or the number of times that a key may be used. 2230 Those security considerations continue to apply when using those 2231 algorithms with JOSE data structures. 2233 8.3. RSAES-PKCS1-v1_5 Security Considerations 2235 While Section 8 of RFC 3447 [RFC3447] explicitly calls for people not 2236 to adopt RSASSA-PKCS-v1_5 for new applications and instead requests 2237 that people transition to RSASSA-PSS, this specification does include 2238 RSASSA-PKCS-v1_5, for interoperability reasons, because it commonly 2239 implemented. 2241 Keys used with RSAES-PKCS1-v1_5 must follow the constraints in 2242 Section 7.2 of RFC 3447 [RFC3447]. In particular, keys with a low 2243 public key exponent value must not be used. 2245 8.4. AES GCM Security Considerations 2247 Keys used with AES GCM must follow the constraints in Section 8.3 of 2248 [NIST.800-38D], which states: "The total number of invocations of the 2249 authenticated encryption function shall not exceed 2^32, including 2250 all IV lengths and all instances of the authenticated encryption 2251 function with the given key". In accordance with this rule, AES GCM 2252 MUST NOT be used with the same key value more than 2^32 times. 2254 An Initialization Vector value MUST never be used multiple times with 2255 the same AES GCM key. One way to prevent this is to store a counter 2256 with the key and increment it with every use. The counter can also 2257 be used to prevent exceeding the 2^32 limit above. 2259 This security consideration does not apply to the composite AES-CBC 2260 HMAC SHA-2 or AES Key Wrap algorithms. 2262 8.5. Plaintext JWS Security Considerations 2264 Plaintext JWSs (JWSs that use the "alg" value "none") provide no 2265 integrity protection. Thus, they must only be used in contexts where 2266 the payload is secured by means other than a digital signature or MAC 2267 value, or need not be secured. 2269 Implementations that support plaintext JWS objects MUST NOT accept 2270 such objects as valid unless the application specifies that it is 2271 acceptable for a specific object to not be integrity-protected. 2272 Implementations MUST NOT accept plaintext JWS objects by default. 2273 For example, the "verify" method of a hypothetical JWS software 2274 library might have a Boolean "acceptUnsigned" parameter that 2275 indicates "none" is an acceptable "alg" value. As another example, 2276 the "verify" method might take a list of algorithms that are 2277 acceptable to the application as a parameter and would reject 2278 plaintext JWS values if "none" is not in that list. 2280 In order to mitigate downgrade attacks, applications MUST NOT signal 2281 acceptance of plaintext JWS objects at a global level, and SHOULD 2282 signal acceptance on a per-object basis. For example, suppose an 2283 application accepts JWS objects over two channels, (1) HTTP and (2) 2284 HTTPS with client authentication. It requires a JWS signature on 2285 objects received over HTTP, but accepts plaintext JWS objects over 2286 HTTPS. If the application were to globally indicate that "none" is 2287 acceptable, then an attacker could provide it with an unsigned object 2288 over HTTP and still have that object successfully validate. Instead, 2289 the application needs to indicate acceptance of "none" for each 2290 object received over HTTPS (e.g., by setting "acceptUnsigned" to 2291 "true" for the first hypothetical JWS software library above), but 2292 not for each object received over HTTP. 2294 8.6. Differences between Digital Signatures and MACs 2296 While in many cases, MACs and digital signatures can be used for 2297 integrity checking, there are some significant differences between 2298 the security properties that each of them provides. These need to be 2299 taken into consideration when designing protocols and selecting the 2300 algorithms to be used in protocols. 2302 Both signatures and MACs provide for integrity checking -- verifying 2303 that the message has not been modified since the integrity value was 2304 computed. However, MACs provide for origination identification only 2305 under specific circumstances. It can normally be assumed that a 2306 private key used for a signature is only in the hands of a single 2307 entity (although perhaps a distributed entity, in the case of 2308 replicated servers); however, a MAC key needs to be in the hands of 2309 all the entities that use it for integrity computation and checking. 2311 This means that origination can only be determined if a MAC key is 2312 known only to two entities and the receiver knows that it did not 2313 create the message. MAC validation cannot be used to prove 2314 origination to a third party. 2316 8.7. Denial of Service Attacks 2318 Receiving agents that validate signatures and sending agents that 2319 encrypt messages need to be cautious of cryptographic processing 2320 usage when validating signatures and encrypting messages using keys 2321 larger than those mandated in this specification. An attacker could 2322 send certificates with keys that would result in excessive 2323 cryptographic processing, for example, keys larger than those 2324 mandated in this specification, which could swamp the processing 2325 element. Agents that use such keys without first validating the 2326 certificate to a trust anchor are advised to have some sort of 2327 cryptographic resource management system to prevent such attacks. 2329 8.8. Reusing Key Material when Encrypting Keys 2331 It is NOT RECOMMENDED to reuse the same key material (Key Encryption 2332 Key, Content Encryption Key, Initialization Vector, etc.) to encrypt 2333 multiple JWK or JWK Set objects, or to encrypt the same JWK or JWK 2334 Set object multiple times. One suggestion for preventing re-use is 2335 to always generate a new set key material for each encryption 2336 operation, based on the considerations noted in this document as well 2337 as from [RFC4086]. 2339 8.9. Password Considerations 2341 Passwords are vulnerable to a number of attacks. To help mitigate 2342 some of these limitations, this document applies principles from 2343 [RFC2898] to derive cryptographic keys from user-supplied passwords. 2345 However, the strength of the password still has a significant impact. 2346 A high-entropy password has greater resistance to dictionary attacks. 2347 [NIST-800-63-1] contains guidelines for estimating password entropy, 2348 which can help applications and users generate stronger passwords. 2350 An ideal password is one that is as large as (or larger than) the 2351 derived key length. However, passwords larger than a certain 2352 algorithm-specific size are first hashed, which reduces an attacker's 2353 effective search space to the length of the hash algorithm. It is 2354 RECOMMENDED that a password used for "PBES2-HS256+A128KW" be no 2355 shorter than 16 octets and no longer than 128 octets and a password 2356 used for "PBES2-HS512+A256KW" be no shorter than 32 octets and no 2357 longer than 128 octets long. 2359 Still, care needs to be taken in where and how password-based 2360 encryption is used. These algorithms can still be susceptible to 2361 dictionary-based attacks if the iteration count is too small; this is 2362 of particular concern if these algorithms are used to protect data 2363 that an attacker can have indefinite number of attempts to circumvent 2364 the protection, such as protected data stored on a file system. 2366 9. Internationalization Considerations 2368 Passwords obtained from users are likely to require preparation and 2369 normalization to account for differences of octet sequences generated 2370 by different input devices, locales, etc. It is RECOMMENDED that 2371 applications to perform the steps outlined in 2372 [I-D.ietf-precis-saslprepbis] to prepare a password supplied directly 2373 by a user before performing key derivation and encryption. 2375 10. References 2377 10.1. Normative References 2379 [AES] National Institute of Standards and Technology (NIST), 2380 "Advanced Encryption Standard (AES)", FIPS PUB 197, 2381 November 2001. 2383 [DSS] National Institute of Standards and Technology, "Digital 2384 Signature Standard (DSS)", FIPS PUB 186-4, July 2013. 2386 [JWE] Jones, M. and J. Hildebrand, "JSON Web Encryption (JWE)", 2387 draft-ietf-jose-json-web-encryption (work in progress), 2388 April 2014. 2390 [JWK] Jones, M., "JSON Web Key (JWK)", 2391 draft-ietf-jose-json-web-key (work in progress), 2392 April 2014. 2394 [JWS] Jones, M., Bradley, J., and N. Sakimura, "JSON Web 2395 Signature (JWS)", draft-ietf-jose-json-web-signature (work 2396 in progress), April 2014. 2398 [NIST.800-38A] 2399 National Institute of Standards and Technology (NIST), 2400 "Recommendation for Block Cipher Modes of Operation", 2401 NIST PUB 800-38A, December 2001. 2403 [NIST.800-38D] 2404 National Institute of Standards and Technology (NIST), 2405 "Recommendation for Block Cipher Modes of Operation: 2406 Galois/Counter Mode (GCM) and GMAC", NIST PUB 800-38D, 2407 December 2001. 2409 [NIST.800-56A] 2410 National Institute of Standards and Technology (NIST), 2411 "Recommendation for Pair-Wise Key Establishment Schemes 2412 Using Discrete Logarithm Cryptography", NIST Special 2413 Publication 800-56A, Revision 2, May 2013. 2415 [RFC2104] Krawczyk, H., Bellare, M., and R. Canetti, "HMAC: Keyed- 2416 Hashing for Message Authentication", RFC 2104, 2417 February 1997. 2419 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 2420 Requirement Levels", BCP 14, RFC 2119, March 1997. 2422 [RFC2898] Kaliski, B., "PKCS #5: Password-Based Cryptography 2423 Specification Version 2.0", RFC 2898, September 2000. 2425 [RFC3394] Schaad, J. and R. Housley, "Advanced Encryption Standard 2426 (AES) Key Wrap Algorithm", RFC 3394, September 2002. 2428 [RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO 2429 10646", STD 63, RFC 3629, November 2003. 2431 [RFC4868] Kelly, S. and S. Frankel, "Using HMAC-SHA-256, HMAC-SHA- 2432 384, and HMAC-SHA-512 with IPsec", RFC 4868, May 2007. 2434 [RFC6090] McGrew, D., Igoe, K., and M. Salter, "Fundamental Elliptic 2435 Curve Cryptography Algorithms", RFC 6090, February 2011. 2437 [RFC7159] Bray, T., "The JavaScript Object Notation (JSON) Data 2438 Interchange Format", RFC 7159, March 2014. 2440 [SEC1] Standards for Efficient Cryptography Group, "SEC 1: 2441 Elliptic Curve Cryptography", May 2009. 2443 [SHS] National Institute of Standards and Technology, "Secure 2444 Hash Standard (SHS)", FIPS PUB 180-3, October 2008. 2446 [USASCII] American National Standards Institute, "Coded Character 2447 Set -- 7-bit American Standard Code for Information 2448 Interchange", ANSI X3.4, 1986. 2450 10.2. Informative References 2452 [CanvasApp] 2453 Facebook, "Canvas Applications", 2010. 2455 [I-D.ietf-precis-saslprepbis] 2456 Saint-Andre, P. and A. Melnikov, "Preparation and 2457 Comparison of Internationalized Strings Representing 2458 Usernames and Passwords", draft-ietf-precis-saslprepbis-07 2459 (work in progress), March 2014. 2461 [I-D.mcgrew-aead-aes-cbc-hmac-sha2] 2462 McGrew, D., Foley, J., and K. Paterson, "Authenticated 2463 Encryption with AES-CBC and HMAC-SHA", 2464 draft-mcgrew-aead-aes-cbc-hmac-sha2-04 (work in progress), 2465 February 2014. 2467 [I-D.miller-jose-jwe-protected-jwk] 2468 Miller, M., "Using JavaScript Object Notation (JSON) Web 2469 Encryption (JWE) for Protecting JSON Web Key (JWK) 2470 Objects", draft-miller-jose-jwe-protected-jwk-02 (work in 2471 progress), June 2013. 2473 [I-D.rescorla-jsms] 2474 Rescorla, E. and J. Hildebrand, "JavaScript Message 2475 Security Format", draft-rescorla-jsms-00 (work in 2476 progress), March 2011. 2478 [JCA] Oracle, "Java Cryptography Architecture", 2013. 2480 [JSE] Bradley, J. and N. Sakimura (editor), "JSON Simple 2481 Encryption", September 2010. 2483 [JSS] Bradley, J. and N. Sakimura (editor), "JSON Simple Sign", 2484 September 2010. 2486 [MagicSignatures] 2487 Panzer (editor), J., Laurie, B., and D. Balfanz, "Magic 2488 Signatures", January 2011. 2490 [NIST-800-63-1] 2491 National Institute of Standards and Technology (NIST), 2492 "Electronic Authentication Guideline", NIST 800-63-1, 2493 December 2011. 2495 [RFC2631] Rescorla, E., "Diffie-Hellman Key Agreement Method", 2496 RFC 2631, June 1999. 2498 [RFC3275] Eastlake, D., Reagle, J., and D. Solo, "(Extensible Markup 2499 Language) XML-Signature Syntax and Processing", RFC 3275, 2500 March 2002. 2502 [RFC3447] Jonsson, J. and B. Kaliski, "Public-Key Cryptography 2503 Standards (PKCS) #1: RSA Cryptography Specifications 2504 Version 2.1", RFC 3447, February 2003. 2506 [RFC4086] Eastlake, D., Schiller, J., and S. Crocker, "Randomness 2507 Requirements for Security", BCP 106, RFC 4086, June 2005. 2509 [RFC5116] McGrew, D., "An Interface and Algorithms for Authenticated 2510 Encryption", RFC 5116, January 2008. 2512 [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an 2513 IANA Considerations Section in RFCs", BCP 26, RFC 5226, 2514 May 2008. 2516 [W3C.NOTE-xmldsig-core2-20130411] 2517 Eastlake, D., Reagle, J., Solo, D., Hirsch, F., Roessler, 2518 T., Yiu, K., Datta, P., and S. Cantor, "XML Signature 2519 Syntax and Processing Version 2.0", World Wide Web 2520 Consortium Note NOTE-xmldsig-core2-20130411, April 2013, 2521 . 2523 [W3C.REC-xmlenc-core-20021210] 2524 Eastlake, D. and J. Reagle, "XML Encryption Syntax and 2525 Processing", World Wide Web Consortium Recommendation REC- 2526 xmlenc-core-20021210, December 2002, 2527 . 2529 [W3C.REC-xmlenc-core1-20130411] 2530 Eastlake, D., Reagle, J., Hirsch, F., and T. Roessler, 2531 "XML Encryption Syntax and Processing Version 1.1", World 2532 Wide Web Consortium Recommendation REC-xmlenc-core1- 2533 20130411, April 2013, 2534 . 2536 Appendix A. Algorithm Identifier Cross-Reference 2538 This appendix contains tables cross-referencing the cryptographic 2539 algorithm identifier values defined in this specification with the 2540 equivalent identifiers used by other standards and software packages. 2541 See XML DSIG [RFC3275], XML DSIG 2.0 2542 [W3C.NOTE-xmldsig-core2-20130411], XML Encryption 2543 [W3C.REC-xmlenc-core-20021210], XML Encryption 1.1 2544 [W3C.REC-xmlenc-core1-20130411], and Java Cryptography Architecture 2546 [JCA] for more information about the names defined by those 2547 documents. 2549 A.1. Digital Signature/MAC Algorithm Identifier Cross-Reference 2551 This section contains a table cross-referencing the JWS digital 2552 signature and MAC "alg" (algorithm) values defined in this 2553 specification with the equivalent identifiers used by other standards 2554 and software packages. 2556 +-----+-------------------------------+--------------+--------------+ 2557 | JWS | XML DSIG | JCA | OID | 2558 +-----+-------------------------------+--------------+--------------+ 2559 | HS2 | http://www.w3.org/2001/04/xml | HmacSHA256 | 1.2.840.1135 | 2560 | 56 | dsig-more#hmac-sha256 | | 49.2.9 | 2561 | HS3 | http://www.w3.org/2001/04/xml | HmacSHA384 | 1.2.840.1135 | 2562 | 84 | dsig-more#hmac-sha384 | | 49.2.10 | 2563 | HS5 | http://www.w3.org/2001/04/xml | HmacSHA512 | 1.2.840.1135 | 2564 | 12 | dsig-more#hmac-sha512 | | 49.2.11 | 2565 | RS2 | http://www.w3.org/2001/04/xml | SHA256withRS | 1.2.840.1135 | 2566 | 56 | dsig-more#rsa-sha256 | A | 49.1.1.11 | 2567 | RS3 | http://www.w3.org/2001/04/xml | SHA384withRS | 1.2.840.1135 | 2568 | 84 | dsig-more#rsa-sha384 | A | 49.1.1.12 | 2569 | RS5 | http://www.w3.org/2001/04/xml | SHA512withRS | 1.2.840.1135 | 2570 | 12 | dsig-more#rsa-sha512 | A | 49.1.1.13 | 2571 | ES2 | http://www.w3.org/2001/04/xml | SHA256withEC | 1.2.840.1004 | 2572 | 56 | dsig-more#ecdsa-sha256 | DSA | 5.4.3.2 | 2573 | ES3 | http://www.w3.org/2001/04/xml | SHA384withEC | 1.2.840.1004 | 2574 | 84 | dsig-more#ecdsa-sha384 | DSA | 5.4.3.3 | 2575 | ES5 | http://www.w3.org/2001/04/xml | SHA512withEC | 1.2.840.1004 | 2576 | 12 | dsig-more#ecdsa-sha512 | DSA | 5.4.3.4 | 2577 | PS2 | http://www.w3.org/2007/05/xml | SHA256withRS | 1.2.840.1135 | 2578 | 56 | dsig-more#sha256-rsa-MGF1 | AandMGF1 | 49.1.1.10 | 2579 | PS3 | http://www.w3.org/2007/05/xml | SHA384withRS | 1.2.840.1135 | 2580 | 84 | dsig-more#sha384-rsa-MGF1 | AandMGF1 | 49.1.1.10 | 2581 | PS5 | http://www.w3.org/2007/05/xml | SHA512withRS | 1.2.840.1135 | 2582 | 12 | dsig-more#sha512-rsa-MGF1 | AandMGF1 | 49.1.1.10 | 2583 +-----+-------------------------------+--------------+--------------+ 2585 A.2. Key Management Algorithm Identifier Cross-Reference 2587 This section contains a table cross-referencing the JWE "alg" 2588 (algorithm) values defined in this specification with the equivalent 2589 identifiers used by other standards and software packages. 2591 +-------+------------------------+--------------------+-------------+ 2592 | JWE | XML ENC | JCA | OID | 2593 +-------+------------------------+--------------------+-------------+ 2594 | RSA1_ | http://www.w3.org/2001 | RSA/ECB/PKCS1Paddi | 1.2.840.113 | 2595 | 5 | /04/xmlenc#rsa-1_5 | ng | 549.1.1.1 | 2596 | RSA-O | http://www.w3.org/2001 | RSA/ECB/OAEPWithSH | 1.2.840.113 | 2597 | AEP | /04/xmlenc#rsa-oaep-mg | A-1AndMGF1Padding | 549.1.1.7 | 2598 | | f1p | | | 2599 | RSA-O | http://www.w3.org/2009 | RSA/ECB/OAEPWithSH | 1.2.840.113 | 2600 | AEP-2 | /xmlenc11#rsa-oaep | A-256AndMGF1Paddin | 549.1.1.7 | 2601 | 56 | | g | | 2602 | ECDH- | http://www.w3.org/2009 | | 1.3.132.1.1 | 2603 | ES | /xmlenc11#ECDH-ES | | 2 | 2604 | A128K | http://www.w3.org/2001 | | 2.16.840.1. | 2605 | W | /04/xmlenc#kw-aes128 | | 101.3.4.1.5 | 2606 | A192K | http://www.w3.org/2001 | | 2.16.840.1. | 2607 | W | /04/xmlenc#kw-aes192 | | 101.3.4.1.2 | 2608 | | | | 5 | 2609 | A256K | http://www.w3.org/2001 | | 2.16.840.1. | 2610 | W | /04/xmlenc#kw-aes256 | | 101.3.4.1.4 | 2611 | | | | 5 | 2612 +-------+------------------------+--------------------+-------------+ 2614 A.3. Content Encryption Algorithm Identifier Cross-Reference 2616 This section contains a table cross-referencing the JWE "enc" 2617 (encryption algorithm) values defined in this specification with the 2618 equivalent identifiers used by other standards and software packages. 2620 For the composite algorithms "A128CBC-HS256", "A192CBC-HS384", and 2621 "A256CBC-HS512", the corresponding AES CBC algorithm identifiers are 2622 listed. 2624 +---------+-------------------------+--------------+----------------+ 2625 | JWE | XML ENC | JCA | OID | 2626 +---------+-------------------------+--------------+----------------+ 2627 | A128CBC | http://www.w3.org/2001/ | AES/CBC/PKCS | 2.16.840.1.101 | 2628 | -HS256 | 04/xmlenc#aes128-cbc | 5Padding | .3.4.1.2 | 2629 | A192CBC | http://www.w3.org/2001/ | AES/CBC/PKCS | 2.16.840.1.101 | 2630 | -HS384 | 04/xmlenc#aes192-cbc | 5Padding | .3.4.1.22 | 2631 | A256CBC | http://www.w3.org/2001/ | AES/CBC/PKCS | 2.16.840.1.101 | 2632 | -HS512 | 04/xmlenc#aes256-cbc | 5Padding | .3.4.1.42 | 2633 | A128GCM | http://www.w3.org/2009/ | AES/GCM/NoPa | 2.16.840.1.101 | 2634 | | xmlenc11#aes128-gcm | dding | .3.4.1.6 | 2635 | A192GCM | http://www.w3.org/2009/ | AES/GCM/NoPa | 2.16.840.1.101 | 2636 | | xmlenc11#aes192-gcm | dding | .3.4.1.26 | 2637 | A256GCM | http://www.w3.org/2009/ | AES/GCM/NoPa | 2.16.840.1.101 | 2638 | | xmlenc11#aes256-gcm | dding | .3.4.1.46 | 2639 +---------+-------------------------+--------------+----------------+ 2641 Appendix B. Test Cases for AES_CBC_HMAC_SHA2 Algorithms 2643 The following test cases can be used to validate implementations of 2644 the AES_CBC_HMAC_SHA2 algorithms defined in Section 5.2. They are 2645 also intended to correspond to test cases that may appear in a future 2646 version of [I-D.mcgrew-aead-aes-cbc-hmac-sha2], demonstrating that 2647 the cryptographic computations performed are the same. 2649 The variable names are those defined in Section 5.2. All values are 2650 hexadecimal. 2652 B.1. Test Cases for AES_128_CBC_HMAC_SHA_256 2654 AES_128_CBC_HMAC_SHA_256 2656 K = 00 01 02 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f 2657 10 11 12 13 14 15 16 17 18 19 1a 1b 1c 1d 1e 1f 2659 MAC_KEY = 00 01 02 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f 2661 ENC_KEY = 10 11 12 13 14 15 16 17 18 19 1a 1b 1c 1d 1e 1f 2663 P = 41 20 63 69 70 68 65 72 20 73 79 73 74 65 6d 20 2664 6d 75 73 74 20 6e 6f 74 20 62 65 20 72 65 71 75 2665 69 72 65 64 20 74 6f 20 62 65 20 73 65 63 72 65 2666 74 2c 20 61 6e 64 20 69 74 20 6d 75 73 74 20 62 2667 65 20 61 62 6c 65 20 74 6f 20 66 61 6c 6c 20 69 2668 6e 74 6f 20 74 68 65 20 68 61 6e 64 73 20 6f 66 2669 20 74 68 65 20 65 6e 65 6d 79 20 77 69 74 68 6f 2670 75 74 20 69 6e 63 6f 6e 76 65 6e 69 65 6e 63 65 2672 IV = 1a f3 8c 2d c2 b9 6f fd d8 66 94 09 23 41 bc 04 2674 A = 54 68 65 20 73 65 63 6f 6e 64 20 70 72 69 6e 63 2675 69 70 6c 65 20 6f 66 20 41 75 67 75 73 74 65 20 2676 4b 65 72 63 6b 68 6f 66 66 73 2678 AL = 00 00 00 00 00 00 01 50 2680 E = c8 0e df a3 2d df 39 d5 ef 00 c0 b4 68 83 42 79 2681 a2 e4 6a 1b 80 49 f7 92 f7 6b fe 54 b9 03 a9 c9 2682 a9 4a c9 b4 7a d2 65 5c 5f 10 f9 ae f7 14 27 e2 2683 fc 6f 9b 3f 39 9a 22 14 89 f1 63 62 c7 03 23 36 2684 09 d4 5a c6 98 64 e3 32 1c f8 29 35 ac 40 96 c8 2685 6e 13 33 14 c5 40 19 e8 ca 79 80 df a4 b9 cf 1b 2686 38 4c 48 6f 3a 54 c5 10 78 15 8e e5 d7 9d e5 9f 2687 bd 34 d8 48 b3 d6 95 50 a6 76 46 34 44 27 ad e5 2688 4b 88 51 ff b5 98 f7 f8 00 74 b9 47 3c 82 e2 db 2690 M = 65 2c 3f a3 6b 0a 7c 5b 32 19 fa b3 a3 0b c1 c4 2691 e6 e5 45 82 47 65 15 f0 ad 9f 75 a2 b7 1c 73 ef 2693 T = 65 2c 3f a3 6b 0a 7c 5b 32 19 fa b3 a3 0b c1 c4 2695 B.2. Test Cases for AES_192_CBC_HMAC_SHA_384 2697 K = 00 01 02 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f 2698 10 11 12 13 14 15 16 17 18 19 1a 1b 1c 1d 1e 1f 2699 20 21 22 23 24 25 26 27 28 29 2a 2b 2c 2d 2e 2f 2701 MAC_KEY = 00 01 02 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f 2702 10 11 12 13 14 15 16 17 2704 ENC_KEY = 18 19 1a 1b 1c 1d 1e 1f 20 21 22 23 24 25 26 27 2705 28 29 2a 2b 2c 2d 2e 2f 2707 P = 41 20 63 69 70 68 65 72 20 73 79 73 74 65 6d 20 2708 6d 75 73 74 20 6e 6f 74 20 62 65 20 72 65 71 75 2709 69 72 65 64 20 74 6f 20 62 65 20 73 65 63 72 65 2710 74 2c 20 61 6e 64 20 69 74 20 6d 75 73 74 20 62 2711 65 20 61 62 6c 65 20 74 6f 20 66 61 6c 6c 20 69 2712 6e 74 6f 20 74 68 65 20 68 61 6e 64 73 20 6f 66 2713 20 74 68 65 20 65 6e 65 6d 79 20 77 69 74 68 6f 2714 75 74 20 69 6e 63 6f 6e 76 65 6e 69 65 6e 63 65 2716 IV = 1a f3 8c 2d c2 b9 6f fd d8 66 94 09 23 41 bc 04 2718 A = 54 68 65 20 73 65 63 6f 6e 64 20 70 72 69 6e 63 2719 69 70 6c 65 20 6f 66 20 41 75 67 75 73 74 65 20 2720 4b 65 72 63 6b 68 6f 66 66 73 2722 AL = 00 00 00 00 00 00 01 50 2724 E = ea 65 da 6b 59 e6 1e db 41 9b e6 2d 19 71 2a e5 2725 d3 03 ee b5 00 52 d0 df d6 69 7f 77 22 4c 8e db 2726 00 0d 27 9b dc 14 c1 07 26 54 bd 30 94 42 30 c6 2727 57 be d4 ca 0c 9f 4a 84 66 f2 2b 22 6d 17 46 21 2728 4b f8 cf c2 40 0a dd 9f 51 26 e4 79 66 3f c9 0b 2729 3b ed 78 7a 2f 0f fc bf 39 04 be 2a 64 1d 5c 21 2730 05 bf e5 91 ba e2 3b 1d 74 49 e5 32 ee f6 0a 9a 2731 c8 bb 6c 6b 01 d3 5d 49 78 7b cd 57 ef 48 49 27 2732 f2 80 ad c9 1a c0 c4 e7 9c 7b 11 ef c6 00 54 e3 2734 M = 84 90 ac 0e 58 94 9b fe 51 87 5d 73 3f 93 ac 20 2735 75 16 80 39 cc c7 33 d7 45 94 f8 86 b3 fa af d4 2736 86 f2 5c 71 31 e3 28 1e 36 c7 a2 d1 30 af de 57 2738 T = 84 90 ac 0e 58 94 9b fe 51 87 5d 73 3f 93 ac 20 2739 75 16 80 39 cc c7 33 d7 2741 B.3. Test Cases for AES_256_CBC_HMAC_SHA_512 2743 K = 00 01 02 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f 2744 10 11 12 13 14 15 16 17 18 19 1a 1b 1c 1d 1e 1f 2745 20 21 22 23 24 25 26 27 28 29 2a 2b 2c 2d 2e 2f 2746 30 31 32 33 34 35 36 37 38 39 3a 3b 3c 3d 3e 3f 2748 MAC_KEY = 00 01 02 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f 2749 10 11 12 13 14 15 16 17 18 19 1a 1b 1c 1d 1e 1f 2751 ENC_KEY = 20 21 22 23 24 25 26 27 28 29 2a 2b 2c 2d 2e 2f 2752 30 31 32 33 34 35 36 37 38 39 3a 3b 3c 3d 3e 3f 2754 P = 41 20 63 69 70 68 65 72 20 73 79 73 74 65 6d 20 2755 6d 75 73 74 20 6e 6f 74 20 62 65 20 72 65 71 75 2756 69 72 65 64 20 74 6f 20 62 65 20 73 65 63 72 65 2757 74 2c 20 61 6e 64 20 69 74 20 6d 75 73 74 20 62 2758 65 20 61 62 6c 65 20 74 6f 20 66 61 6c 6c 20 69 2759 6e 74 6f 20 74 68 65 20 68 61 6e 64 73 20 6f 66 2760 20 74 68 65 20 65 6e 65 6d 79 20 77 69 74 68 6f 2761 75 74 20 69 6e 63 6f 6e 76 65 6e 69 65 6e 63 65 2763 IV = 1a f3 8c 2d c2 b9 6f fd d8 66 94 09 23 41 bc 04 2765 A = 54 68 65 20 73 65 63 6f 6e 64 20 70 72 69 6e 63 2766 69 70 6c 65 20 6f 66 20 41 75 67 75 73 74 65 20 2767 4b 65 72 63 6b 68 6f 66 66 73 2769 AL = 00 00 00 00 00 00 01 50 2771 E = 4a ff aa ad b7 8c 31 c5 da 4b 1b 59 0d 10 ff bd 2772 3d d8 d5 d3 02 42 35 26 91 2d a0 37 ec bc c7 bd 2773 82 2c 30 1d d6 7c 37 3b cc b5 84 ad 3e 92 79 c2 2774 e6 d1 2a 13 74 b7 7f 07 75 53 df 82 94 10 44 6b 2775 36 eb d9 70 66 29 6a e6 42 7e a7 5c 2e 08 46 a1 2776 1a 09 cc f5 37 0d c8 0b fe cb ad 28 c7 3f 09 b3 2777 a3 b7 5e 66 2a 25 94 41 0a e4 96 b2 e2 e6 60 9e 2778 31 e6 e0 2c c8 37 f0 53 d2 1f 37 ff 4f 51 95 0b 2779 be 26 38 d0 9d d7 a4 93 09 30 80 6d 07 03 b1 f6 2781 M = 4d d3 b4 c0 88 a7 f4 5c 21 68 39 64 5b 20 12 bf 2782 2e 62 69 a8 c5 6a 81 6d bc 1b 26 77 61 95 5b c5 2783 fd 30 a5 65 c6 16 ff b2 f3 64 ba ec e6 8f c4 07 2784 53 bc fc 02 5d de 36 93 75 4a a1 f5 c3 37 3b 9c 2786 T = 4d d3 b4 c0 88 a7 f4 5c 21 68 39 64 5b 20 12 bf 2787 2e 62 69 a8 c5 6a 81 6d bc 1b 26 77 61 95 5b c5 2789 Appendix C. Example ECDH-ES Key Agreement Computation 2791 This example uses ECDH-ES Key Agreement and the Concat KDF to derive 2792 the Content Encryption Key (CEK) in the manner described in 2793 Section 4.6. In this example, the ECDH-ES Direct Key Agreement mode 2794 ("alg" value "ECDH-ES") is used to produce an agreed upon key for AES 2795 GCM with a 128 bit key ("enc" value "A128GCM"). 2797 In this example, a sender Alice is encrypting content to a recipient 2798 Bob. The sender (Alice) generates an ephemeral key for the key 2799 agreement computation. Alice's ephemeral key (in JWK format) used 2800 for the key agreement computation in this example (including the 2801 private part) is: 2803 {"kty":"EC", 2804 "crv":"P-256", 2805 "x":"gI0GAILBdu7T53akrFmMyGcsF3n5dO7MmwNBHKW5SV0", 2806 "y":"SLW_xSffzlPWrHEVI30DHM_4egVwt3NQqeUD7nMFpps", 2807 "d":"0_NxaRPUMQoAJt50Gz8YiTr8gRTwyEaCumd-MToTmIo" 2808 } 2810 The recipient's (Bob's) key (in JWK format) used for the key 2811 agreement computation in this example (including the private part) 2812 is: 2814 {"kty":"EC", 2815 "crv":"P-256", 2816 "x":"weNJy2HscCSM6AEDTDg04biOvhFhyyWvOHQfeF_PxMQ", 2817 "y":"e8lnCO-AlStT-NJVX-crhB7QRYhiix03illJOVAOyck", 2818 "d":"VEmDZpDXXK8p8N0Cndsxs924q6nS1RXFASRl6BfUqdw" 2819 } 2821 Header Parameter values used in this example are as follows. In this 2822 example, the "apu" (agreement PartyUInfo) parameter value is the 2823 base64url encoding of the UTF-8 string "Alice" and the "apv" 2824 (agreement PartyVInfo) parameter value is the base64url encoding of 2825 the UTF-8 string "Bob". The "epk" parameter is used to communicate 2826 the sender's (Alice's) ephemeral public key value to the recipient 2827 (Bob). 2829 {"alg":"ECDH-ES", 2830 "enc":"A128GCM", 2831 "apu":"QWxpY2U", 2832 "apv":"Qm9i", 2833 "epk": 2834 {"kty":"EC", 2835 "crv":"P-256", 2836 "x":"gI0GAILBdu7T53akrFmMyGcsF3n5dO7MmwNBHKW5SV0", 2837 "y":"SLW_xSffzlPWrHEVI30DHM_4egVwt3NQqeUD7nMFpps" 2838 } 2839 } 2841 The resulting Concat KDF [NIST.800-56A] parameter values are: 2843 Z 2844 This is set to the ECDH-ES key agreement output. (This value is 2845 often not directly exposed by libraries, due to NIST security 2846 requirements, and only serves as an input to a KDF.) In this 2847 example, Z is following the octet sequence (using JSON array 2848 notation): 2849 [158, 86, 217, 29, 129, 113, 53, 211, 114, 131, 66, 131, 191, 132, 2850 38, 156, 251, 49, 110, 163, 218, 128, 106, 72, 246, 218, 167, 121, 2851 140, 254, 144, 196]. 2853 keydatalen 2854 This value is 128 - the number of bits in the desired output key 2855 (because "A128GCM" uses a 128 bit key). 2857 AlgorithmID 2858 This is set to the octets representing the 32 bit big endian value 2859 7 - [0, 0, 0, 7] - the number of octets in the AlgorithmID content 2860 "A128GCM", followed, by the octets representing the UTF-8 string 2861 "A128GCM" - [65, 49, 50, 56, 71, 67, 77]. 2863 PartyUInfo 2864 This is set to the octets representing the 32 bit big endian value 2865 5 - [0, 0, 0, 5] - the number of octets in the PartyUInfo content 2866 "Alice", followed, by the octets representing the UTF-8 string 2867 "Alice" - [65, 108, 105, 99, 101]. 2869 PartyVInfo 2870 This is set to the octets representing the 32 bit big endian value 2871 3 - [0, 0, 0, 3] - the number of octets in the PartyUInfo content 2872 "Bob", followed, by the octets representing the UTF-8 string "Bob" 2873 - [66, 111, 98]. 2875 SuppPubInfo 2876 This is set to the octets representing the 32 bit big endian value 2877 128 - [0, 0, 0, 128] - the keydatalen value. 2879 SuppPrivInfo 2880 This is set to the empty octet sequence. 2882 Concatenating the parameters AlgorithmID through SuppPubInfo results 2883 in an OtherInfo value of: 2884 [0, 0, 0, 7, 65, 49, 50, 56, 71, 67, 77, 0, 0, 0, 5, 65, 108, 105, 2885 99, 101, 0, 0, 0, 3, 66, 111, 98, 0, 0, 0, 128] 2887 Concatenating the round number 1 ([0, 0, 0, 1]), Z, and the OtherInfo 2888 value results in the Concat KDF round 1 hash input of: 2889 [0, 0, 0, 1, 2890 158, 86, 217, 29, 129, 113, 53, 211, 114, 131, 66, 131, 191, 132, 38, 2891 156, 251, 49, 110, 163, 218, 128, 106, 72, 246, 218, 167, 121, 140, 2892 254, 144, 196, 2893 0, 0, 0, 7, 65, 49, 50, 56, 71, 67, 77, 0, 0, 0, 5, 65, 108, 105, 99, 2894 101, 0, 0, 0, 3, 66, 111, 98, 0, 0, 0, 128] 2896 The resulting derived key, which is the first 128 bits of the round 1 2897 hash output is: 2898 [86, 170, 141, 234, 248, 35, 109, 32, 92, 34, 40, 205, 113, 167, 16, 2899 26] 2901 The base64url encoded representation of this derived key is: 2903 VqqN6vgjbSBcIijNcacQGg 2905 Appendix D. Acknowledgements 2907 Solutions for signing and encrypting JSON content were previously 2908 explored by Magic Signatures [MagicSignatures], JSON Simple Sign 2909 [JSS], Canvas Applications [CanvasApp], JSON Simple Encryption [JSE], 2910 and JavaScript Message Security Format [I-D.rescorla-jsms], all of 2911 which influenced this draft. 2913 The Authenticated Encryption with AES-CBC and HMAC-SHA 2914 [I-D.mcgrew-aead-aes-cbc-hmac-sha2] specification, upon which the 2915 AES_CBC_HMAC_SHA2 algorithms are based, was written by David A. 2916 McGrew and Kenny Paterson. The test cases for AES_CBC_HMAC_SHA2 are 2917 based upon those for [I-D.mcgrew-aead-aes-cbc-hmac-sha2] by John 2918 Foley. 2920 Matt Miller wrote Using JavaScript Object Notation (JSON) Web 2921 Encryption (JWE) for Protecting JSON Web Key (JWK) Objects 2923 [I-D.miller-jose-jwe-protected-jwk], which the password-based 2924 encryption content of this draft is based upon. 2926 This specification is the work of the JOSE Working Group, which 2927 includes dozens of active and dedicated participants. In particular, 2928 the following individuals contributed ideas, feedback, and wording 2929 that influenced this specification: 2931 Dirk Balfanz, Richard Barnes, John Bradley, Brian Campbell, Breno de 2932 Medeiros, Vladimir Dzhuvinov, Yaron Y. Goland, Dick Hardt, Joe 2933 Hildebrand, Jeff Hodges, Edmund Jay, James Manger, Matt Miller, Tony 2934 Nadalin, Axel Nennker, John Panzer, Emmanuel Raviart, Eric Rescorla, 2935 Nat Sakimura, Jim Schaad, Hannes Tschofenig, and Sean Turner. 2937 Jim Schaad and Karen O'Donoghue chaired the JOSE working group and 2938 Sean Turner, Stephen Farrell, and Kathleen Moriarty served as 2939 Security area directors during the creation of this specification. 2941 Appendix E. Document History 2943 [[ to be removed by the RFC Editor before publication as an RFC ]] 2945 -26 2947 o Added algorithm identifier "RSA-OAEP-256" for RSAES OAEP using 2948 SHA-256 and MGF1 with SHA-256. 2950 o Clarified that the ECDSA signature values R and S are represented 2951 as octet sequences as defined in Section 2.3.7 of SEC1 [SEC1]. 2953 o Noted that octet sequences are depicted using JSON array notation. 2955 o Updated references, including to W3C specifications. 2957 -25 2959 o Corrected an external section number reference that had changed. 2961 -24 2963 o Replaced uses of the term "associated data" wherever it was used 2964 to refer to a data value with "additional authenticated data", 2965 since both terms were being used as synonyms, causing confusion. 2967 o Updated the JSON reference to RFC 7159. 2969 -23 2970 o No changes were made, other than to the version number and date. 2972 -22 2974 o Corrected RFC 2119 terminology usage. 2976 o Replaced references to draft-ietf-json-rfc4627bis with RFC 7158. 2978 -21 2980 o Compute the PBES2 salt parameter as (UTF8(Alg) || 0x00 || Salt 2981 Input), where the "p2s" Header Parameter encodes the Salt Input 2982 value and Alg is the "alg" Header Parameter value. 2984 o Changed some references from being normative to informative, 2985 addressing issue #90. 2987 -20 2989 o Replaced references to RFC 4627 with draft-ietf-json-rfc4627bis, 2990 addressing issue #90. 2992 -19 2994 o Used tables to show the correspondence between algorithm 2995 identifiers and algorithm descriptions and parameters in the 2996 algorithm definition sections, addressing issue #183. 2998 o Changed the "Implementation Requirements" registry field names to 2999 "JOSE Implementation Requirements" to make it clear that these 3000 implementation requirements apply only to JWS and JWE 3001 implementations. 3003 -18 3005 o Changes to address editorial and minor issues #129, #134, #135, 3006 #158, #161, #185, #186, and #187. 3008 o Added and used Description registry fields. 3010 -17 3012 o Explicitly named all the logical components of a JWS and JWE and 3013 defined the processing rules and serializations in terms of those 3014 components, addressing issues #60, #61, and #62. 3016 o Removed processing steps in algorithm definitions that duplicated 3017 processing steps in JWS or JWE, addressing issue #56. 3019 o Replaced verbose repetitive phases such as "base64url encode the 3020 octets of the UTF-8 representation of X" with mathematical 3021 notation such as "BASE64URL(UTF8(X))". 3023 o Terms used in multiple documents are now defined in one place and 3024 incorporated by reference. Some lightly used or obvious terms 3025 were also removed. This addresses issue #58. 3027 o Changes to address minor issue #53. 3029 -16 3031 o Added a DataLen prefix to the AlgorithmID value in the Concat KDF 3032 computation. 3034 o Added OIDs for encryption algorithms, additional signature 3035 algorithm OIDs, and additional XML DSIG/ENC URIs in the algorithm 3036 cross-reference tables. 3038 o Changes to address editorial and minor issues #28, #36, #39, #52, 3039 #53, #55, #127, #128, #136, #137, #141, #150, #151, #152, and 3040 #155. 3042 -15 3044 o Changed statements about rejecting JWSs to statements about 3045 validation failing, addressing issue #35. 3047 o Stated that changes of implementation requirements are only 3048 permitted on a Specification Required basis, addressing issue #38. 3050 o Made "oct" a required key type, addressing issue #40. 3052 o Updated the example ECDH-ES key agreement values. 3054 o Changes to address editorial and minor issues #34, #37, #49, #63, 3055 #123, #124, #125, #130, #132, #133, #138, #139, #140, #142, #143, 3056 #144, #145, #148, #149, #150, and #162. 3058 -14 3060 o Removed "PBKDF2" key type and added "p2s" and "p2c" header 3061 parameters for use with the PBES2 algorithms. 3063 o Made the RSA private key parameters that are there to enable 3064 optimizations be RECOMMENDED rather than REQUIRED. 3066 o Added algorithm identifiers for AES algorithms using 192 bit keys 3067 and for RSASSA-PSS using HMAC SHA-384. 3069 o Added security considerations about key lifetimes, addressing 3070 issue #18. 3072 o Added an example ECDH-ES key agreement computation. 3074 -13 3076 o Added key encryption with AES GCM as specified in 3077 draft-jones-jose-aes-gcm-key-wrap-01, addressing issue #13. 3079 o Added security considerations text limiting the number of times 3080 that an AES GCM key can be used for key encryption or direct 3081 encryption, per Section 8.3 of NIST SP 800-38D, addressing issue 3082 #28. 3084 o Added password-based key encryption as specified in 3085 draft-miller-jose-jwe-protected-jwk-02. 3087 -12 3089 o In the Direct Key Agreement case, the Concat KDF AlgorithmID is 3090 set to the octets of the UTF-8 representation of the "enc" header 3091 parameter value. 3093 o Restored the "apv" (agreement PartyVInfo) parameter. 3095 o Moved the "epk", "apu", and "apv" Header Parameter definitions to 3096 be with the algorithm descriptions that use them. 3098 o Changed terminology from "block encryption" to "content 3099 encryption". 3101 -11 3103 o Removed the Encrypted Key value from the AAD computation since it 3104 is already effectively integrity protected by the encryption 3105 process. The AAD value now only contains the representation of 3106 the JWE Encrypted Header. 3108 o Removed "apv" (agreement PartyVInfo) since it is no longer used. 3110 o Added more information about the use of PartyUInfo during key 3111 agreement. 3113 o Use the keydatalen as the SuppPubInfo value for the Concat KDF 3114 when doing key agreement, as RFC 2631 does. 3116 o Added algorithm identifiers for RSASSA-PSS with SHA-256 and SHA- 3117 512. 3119 o Added a Parameter Information Class value to the JSON Web Key 3120 Parameters registry, which registers whether the parameter conveys 3121 public or private information. 3123 -10 3125 o Changed the JWE processing rules for multiple recipients so that a 3126 single AAD value contains the header parameters and encrypted key 3127 values for all the recipients, enabling AES GCM to be safely used 3128 for multiple recipients. 3130 -09 3132 o Expanded the scope of the JWK parameters to include private and 3133 symmetric key representations, as specified by 3134 draft-jones-jose-json-private-and-symmetric-key-00. 3136 o Changed term "JWS Secured Input" to "JWS Signing Input". 3138 o Changed from using the term "byte" to "octet" when referring to 8 3139 bit values. 3141 o Specified that AES Key Wrap uses the default initial value 3142 specified in Section 2.2.3.1 of RFC 3394. This addressed issue 3143 #19. 3145 o Added Key Management Mode definitions to terminology section and 3146 used the defined terms to provide clearer key management 3147 instructions. This addressed issue #5. 3149 o Replaced "A128CBC+HS256" and "A256CBC+HS512" with "A128CBC-HS256" 3150 and "A256CBC-HS512". The new algorithms perform the same 3151 cryptographic computations as [I-D.mcgrew-aead-aes-cbc-hmac-sha2], 3152 but with the Initialization Vector and Authentication Tag values 3153 remaining separate from the Ciphertext value in the output 3154 representation. Also deleted the header parameters "epu" 3155 (encryption PartyUInfo) and "epv" (encryption PartyVInfo), since 3156 they are no longer used. 3158 o Changed from using the term "Integrity Value" to "Authentication 3159 Tag". 3161 -08 3163 o Changed the name of the JWK key type parameter from "alg" to 3164 "kty". 3166 o Replaced uses of the term "AEAD" with "Authenticated Encryption", 3167 since the term AEAD in the RFC 5116 sense implied the use of a 3168 particular data representation, rather than just referring to the 3169 class of algorithms that perform authenticated encryption with 3170 associated data. 3172 o Applied editorial improvements suggested by Jeff Hodges. Many of 3173 these simplified the terminology used. 3175 o Added seriesInfo information to Internet Draft references. 3177 -07 3179 o Added a data length prefix to PartyUInfo and PartyVInfo values. 3181 o Changed the name of the JWK RSA modulus parameter from "mod" to 3182 "n" and the name of the JWK RSA exponent parameter from "xpo" to 3183 "e", so that the identifiers are the same as those used in RFC 3184 3447. 3186 o Made several local editorial changes to clean up loose ends left 3187 over from to the decision to only support block encryption methods 3188 providing integrity. 3190 -06 3192 o Removed the "int" and "kdf" parameters and defined the new 3193 composite Authenticated Encryption algorithms "A128CBC+HS256" and 3194 "A256CBC+HS512" to replace the former uses of AES CBC, which 3195 required the use of separate integrity and key derivation 3196 functions. 3198 o Included additional values in the Concat KDF calculation -- the 3199 desired output size and the algorithm value, and optionally 3200 PartyUInfo and PartyVInfo values. Added the optional header 3201 parameters "apu" (agreement PartyUInfo), "apv" (agreement 3202 PartyVInfo), "epu" (encryption PartyUInfo), and "epv" (encryption 3203 PartyVInfo). 3205 o Changed the name of the JWK RSA exponent parameter from "exp" to 3206 "xpo" so as to allow the potential use of the name "exp" for a 3207 future extension that might define an expiration parameter for 3208 keys. (The "exp" name is already used for this purpose in the JWT 3209 specification.) 3211 o Applied changes made by the RFC Editor to RFC 6749's registry 3212 language to this specification. 3214 -05 3216 o Support both direct encryption using a shared or agreed upon 3217 symmetric key, and the use of a shared or agreed upon symmetric 3218 key to key wrap the CMK. Specifically, added the "alg" values 3219 "dir", "ECDH-ES+A128KW", and "ECDH-ES+A256KW" to finish filling in 3220 this set of capabilities. 3222 o Updated open issues. 3224 -04 3226 o Added text requiring that any leading zero bytes be retained in 3227 base64url encoded key value representations for fixed-length 3228 values. 3230 o Added this language to Registration Templates: "This name is case 3231 sensitive. Names that match other registered names in a case 3232 insensitive manner SHOULD NOT be accepted." 3234 o Described additional open issues. 3236 o Applied editorial suggestions. 3238 -03 3240 o Always use a 128 bit "authentication tag" size for AES GCM, 3241 regardless of the key size. 3243 o Specified that use of a 128 bit IV is REQUIRED with AES CBC. It 3244 was previously RECOMMENDED. 3246 o Removed key size language for ECDSA algorithms, since the key size 3247 is implied by the algorithm being used. 3249 o Stated that the "int" key size must be the same as the hash output 3250 size (and not larger, as was previously allowed) so that its size 3251 is defined for key generation purposes. 3253 o Added the "kdf" (key derivation function) header parameter to 3254 provide crypto agility for key derivation. The default KDF 3255 remains the Concat KDF with the SHA-256 digest function. 3257 o Clarified that the "mod" and "exp" values are unsigned. 3259 o Added Implementation Requirements columns to algorithm tables and 3260 Implementation Requirements entries to algorithm registries. 3262 o Changed AES Key Wrap to RECOMMENDED. 3264 o Moved registries JSON Web Signature and Encryption Header 3265 Parameters and JSON Web Signature and Encryption Type Values to 3266 the JWS specification. 3268 o Moved JSON Web Key Parameters registry to the JWK specification. 3270 o Changed registration requirements from RFC Required to 3271 Specification Required with Expert Review. 3273 o Added Registration Template sections for defined registries. 3275 o Added Registry Contents sections to populate registry values. 3277 o No longer say "the UTF-8 representation of the JWS Secured Input 3278 (which is the same as the ASCII representation)". Just call it 3279 "the ASCII representation of the JWS Secured Input". 3281 o Added "Collision Resistant Namespace" to the terminology section. 3283 o Numerous editorial improvements. 3285 -02 3287 o For AES GCM, use the "additional authenticated data" parameter to 3288 provide integrity for the header, encrypted key, and ciphertext 3289 and use the resulting "authentication tag" value as the JWE 3290 Authentication Tag. 3292 o Defined minimum required key sizes for algorithms without 3293 specified key sizes. 3295 o Defined KDF output key sizes. 3297 o Specified the use of PKCS #5 padding with AES CBC. 3299 o Generalized text to allow key agreement to be employed as an 3300 alternative to key wrapping or key encryption. 3302 o Clarified that ECDH-ES is a key agreement algorithm. 3304 o Required implementation of AES-128-KW and AES-256-KW. 3306 o Removed the use of "A128GCM" and "A256GCM" for key wrapping. 3308 o Removed "A512KW" since it turns out that it's not a standard 3309 algorithm. 3311 o Clarified the relationship between "typ" header parameter values 3312 and MIME types. 3314 o Generalized language to refer to Message Authentication Codes 3315 (MACs) rather than Hash-based Message Authentication Codes (HMACs) 3316 unless in a context specific to HMAC algorithms. 3318 o Established registries: JSON Web Signature and Encryption Header 3319 Parameters, JSON Web Signature and Encryption Algorithms, JSON Web 3320 Signature and Encryption "typ" Values, JSON Web Key Parameters, 3321 and JSON Web Key Algorithm Families. 3323 o Moved algorithm-specific definitions from JWK to JWA. 3325 o Reformatted to give each member definition its own section 3326 heading. 3328 -01 3330 o Moved definition of "alg":"none" for JWSs here from the JWT 3331 specification since this functionality is likely to be useful in 3332 more contexts that just for JWTs. 3334 o Added Advanced Encryption Standard (AES) Key Wrap Algorithm using 3335 512 bit keys ("A512KW"). 3337 o Added text "Alternatively, the Encoded JWS Signature MAY be 3338 base64url decoded to produce the JWS Signature and this value can 3339 be compared with the computed HMAC value, as this comparison 3340 produces the same result as comparing the encoded values". 3342 o Corrected the Magic Signatures reference. 3344 o Made other editorial improvements suggested by JOSE working group 3345 participants. 3347 -00 3349 o Created the initial IETF draft based upon 3350 draft-jones-json-web-signature-04 and 3351 draft-jones-json-web-encryption-02 with no normative changes. 3353 o Changed terminology to no longer call both digital signatures and 3354 HMACs "signatures". 3356 Author's Address 3358 Michael B. Jones 3359 Microsoft 3361 Email: mbj@microsoft.com 3362 URI: http://self-issued.info/