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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group M. Nottingham 3 Internet-Draft Fastly 4 Intended status: Informational P. Sikora 5 Expires: August 24, 2019 Google 6 February 20, 2019 8 The Proxy-Status HTTP Header Field 9 draft-nottingham-proxy-status-00 11 Abstract 13 This document defines the Proxy-Status HTTP header field to convey 14 the details of errors generated by HTTP intermediaries. 16 Note to Readers 18 _RFC EDITOR: please remove this section before publication_ 20 The issues list for this draft can be found at 21 https://github.com/mnot/I-D/labels/proxy-status [1]. 23 The most recent (often, unpublished) draft is at 24 https://mnot.github.io/I-D/proxy-status/ [2]. 26 See also the draft's current status in the IETF datatracker, at 27 https://datatracker.ietf.org/doc/draft-nottingham-proxy-status/ [3]. 29 Precursors that informed this work include (but are not limited to): 31 o https://docs.fastly.com/guides/debugging/common-503-errors 33 o https://support.cloudflare.com/hc/en-us/sections/200820298-Error- 34 Pages 36 o https://cloud.google.com/load-balancing/docs/https/https-logging- 37 monitoring 39 o https://docs.google.com/document/ 40 d/1fMEK80KlpHcL4CwhniOupgQu4MDsxK4y4dKhthjjCMA 42 Status of This Memo 44 This Internet-Draft is submitted in full conformance with the 45 provisions of BCP 78 and BCP 79. 47 Internet-Drafts are working documents of the Internet Engineering 48 Task Force (IETF). Note that other groups may also distribute 49 working documents as Internet-Drafts. The list of current Internet- 50 Drafts is at https://datatracker.ietf.org/drafts/current/. 52 Internet-Drafts are draft documents valid for a maximum of six months 53 and may be updated, replaced, or obsoleted by other documents at any 54 time. It is inappropriate to use Internet-Drafts as reference 55 material or to cite them other than as "work in progress." 57 This Internet-Draft will expire on August 24, 2019. 59 Copyright Notice 61 Copyright (c) 2019 IETF Trust and the persons identified as the 62 document authors. All rights reserved. 64 This document is subject to BCP 78 and the IETF Trust's Legal 65 Provisions Relating to IETF Documents 66 (https://trustee.ietf.org/license-info) in effect on the date of 67 publication of this document. Please review these documents 68 carefully, as they describe your rights and restrictions with respect 69 to this document. Code Components extracted from this document must 70 include Simplified BSD License text as described in Section 4.e of 71 the Trust Legal Provisions and are provided without warranty as 72 described in the Simplified BSD License. 74 Table of Contents 76 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 77 1.1. Notational Conventions . . . . . . . . . . . . . . . . . 4 78 2. The Proxy-Status HTTP Header Field . . . . . . . . . . . . . 4 79 2.1. Generic Proxy Status Parameters . . . . . . . . . . . . . 5 80 3. Proxy Status Types . . . . . . . . . . . . . . . . . . . . . 6 81 3.1. DNS Timeout . . . . . . . . . . . . . . . . . . . . . . . 6 82 3.2. DNS Error . . . . . . . . . . . . . . . . . . . . . . . . 6 83 3.3. Destination Not Found . . . . . . . . . . . . . . . . . . 6 84 3.4. Destination Unavailable . . . . . . . . . . . . . . . . . 7 85 3.5. Destination IP Prohibited . . . . . . . . . . . . . . . . 7 86 3.6. Destination IP Unroutable . . . . . . . . . . . . . . . . 7 87 3.7. Connection Refused . . . . . . . . . . . . . . . . . . . 7 88 3.8. Connection Terminated . . . . . . . . . . . . . . . . . . 8 89 3.9. Connection Timeout . . . . . . . . . . . . . . . . . . . 8 90 3.10. Connection Read Timeout . . . . . . . . . . . . . . . . . 8 91 3.11. Connection Write Timeout . . . . . . . . . . . . . . . . 8 92 3.12. Connection Limit Reached . . . . . . . . . . . . . . . . 9 93 3.13. HTTP Response Status . . . . . . . . . . . . . . . . . . 9 94 3.14. HTTP Incomplete Response . . . . . . . . . . . . . . . . 9 95 3.15. HTTP Protocol Error . . . . . . . . . . . . . . . . . . . 9 96 3.16. HTTP Response Header Block Too Large . . . . . . . . . . 10 97 3.17. HTTP Response Header Too Large . . . . . . . . . . . . . 10 98 3.18. HTTP Response Body Too Large . . . . . . . . . . . . . . 10 99 3.19. HTTP Response Transfer-Coding Error . . . . . . . . . . . 11 100 3.20. HTTP Response Content-Coding Error . . . . . . . . . . . 11 101 3.21. HTTP Response Timeout . . . . . . . . . . . . . . . . . . 11 102 3.22. TLS Handshake Error . . . . . . . . . . . . . . . . . . . 12 103 3.23. TLS Untrusted Peer Certificate . . . . . . . . . . . . . 12 104 3.24. TLS Expired Peer Certificate . . . . . . . . . . . . . . 12 105 3.25. TLS Unexpected Peer Certificate . . . . . . . . . . . . . 12 106 3.26. TLS Unexpected Peer Identity . . . . . . . . . . . . . . 13 107 3.27. TLS Missing Proxy Certificate . . . . . . . . . . . . . . 13 108 3.28. TLS Rejected Proxy Certificate . . . . . . . . . . . . . 13 109 3.29. TLS Error . . . . . . . . . . . . . . . . . . . . . . . . 13 110 3.30. HTTP Request Error . . . . . . . . . . . . . . . . . . . 14 111 3.31. HTTP Request Denied . . . . . . . . . . . . . . . . . . . 14 112 3.32. HTTP Upgrade Failed . . . . . . . . . . . . . . . . . . . 14 113 3.33. Proxy Internal Error . . . . . . . . . . . . . . . . . . 14 114 4. Defining New Proxy Status Types . . . . . . . . . . . . . . . 15 115 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16 116 6. Security Considerations . . . . . . . . . . . . . . . . . . . 16 117 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 16 118 7.1. Normative References . . . . . . . . . . . . . . . . . . 16 119 7.2. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 17 120 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17 122 1. Introduction 124 HTTP intermediaries - including both forward proxies and gateways 125 (also known as "reverse proxies") - have become an increasingly 126 significant part of HTTP deployments. In particular, reverse proxies 127 and Content Delivery Networks (CDNs) form part of the critical 128 infrastructure of many Web sites. 130 Typically, HTTP intermediaries forward requests towards the origin 131 server and then forward their responses back to clients. However, if 132 an error occurs, the response is generated by the intermediary 133 itself. 135 HTTP accommodates these types of errors with a few status codes; for 136 example, 502 Bad Gateway and 504 Gateway Timeout. However, 137 experience has shown that more information is necessary to aid 138 debugging and communicate what's happened to the client. 140 To address this, Section 2 defines a new HTTP response header field 141 to convey such information, using the Proxy Status Types defined in 142 Section 3. Section 4 explains how to define new Proxy Status Types. 144 1.1. Notational Conventions 146 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 147 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 148 "OPTIONAL" in this document are to be interpreted as described in BCP 149 14 [RFC2119] [RFC8174] when, and only when, they appear in all 150 capitals, as shown here. 152 This specification uses Structured Headers 153 [I-D.ietf-httpbis-header-structure] to specify syntax. The terms sh- 154 param-list, sh-item, sh-string, sh-token and sh-integer refer to the 155 structured types defined therein. 157 Note that in this specification, "proxy" is used to indicate both 158 forward and reverse proxies, otherwise known as gateways. "Next hop" 159 indicates the connection in the direction leading to the origin 160 server for the request. 162 2. The Proxy-Status HTTP Header Field 164 The Proxy-Status HTTP response header field allows an intermediary to 165 indicate the nature and details of an error condition it encounters 166 when servicing a request. 168 It is a Structured Headers [I-D.ietf-httpbis-header-structure] 169 Parameterised List, where each item in the list indicates an error 170 condition. Typically, it will have only one param-item (the error 171 condition that triggered generation of the response it occurs 172 within), but more than one value is not prohibited. 174 Each param-item's primary-id is a Proxy Status Type, a registered 175 value that indicates the nature of the error. 177 Each param-item can have zero to many parameters. Section 2.1 lists 178 parameters that can be used with all Proxy Status Types; individual 179 types can define additional parameters to use with them. All 180 parameters are optional; see Section 6 for their potential security 181 impact. 183 For example: 185 HTTP/1.1 504 Gateway Timeout 186 Proxy-Status: connection_timeout; proxy=SomeCDN; origin=abc; tries=3 188 indicates the specific nature of the timeout as a connect timeout to 189 the origin with the identifier "abc", and that is was generated by 190 the intermediary that identifies itself as "FooCDN." Furthermore, 191 three connection attempts were made. 193 Or: 195 HTTP/1.1 429 Too Many Requests 196 Proxy-Status: http_request_error; proxy=SomeReverseProxy 198 indicates that this 429 Too Many Requests response was generated by 199 the intermediary, not the origin. 201 Each Proxy Status Type has a Recommended HTTP Status Code. When 202 generating a HTTP response containing Proxy-Status, its HTTP status 203 code SHOULD be set to the Recommended HTTP Status Code. However, 204 there may be circumstances (e.g., for backwards compatibility with 205 previous behaviours) when another status code might be used. 207 Section 3 lists the Proxy Status Types defined in this document; new 208 ones can be defined using the procedure outlined in Section 4. 210 Proxy-Status MAY be sent in HTTP trailers, but - as with all trailers 211 - it might be silently discarded along the path to the user agent, 212 this SHOULD NOT be done unless it is not possible to send it in 213 headers. For example, if an intermediary is streaming a response and 214 the upstream connection suddenly terminates, Proxy-Status can be 215 appended to the trailers of the outgoing message (since the headers 216 have already been sent). 218 Note that there are various security considerations for 219 intermediaries using the Proxy-Status header field; see Section 6. 221 Origin servers MUST NOT generate the Proxy-Status header field. 223 2.1. Generic Proxy Status Parameters 225 This section lists parameters that are potentially applicable to most 226 Proxy Status Types. 228 o proxy - a sh-token identifying the HTTP intermediary generating 229 this response. 231 o origin - a sh-token identifying the origin server whose behaviour 232 triggered this response. 234 o protocol - a sh-token indicating the ALPN protocol identifier 235 [RFC7301] used to connect to the next hop. This is only 236 applicable when that connection was actually established. 238 o tries - a sh-integer indicating the number of times that the error 239 has occurred before this response. 241 o details - a sh-string containing additional information not 242 captured anywhere else. This can include implementation-specific 243 or deployment-specific information. 245 3. Proxy Status Types 247 This section lists the Proxy Status Types defined by this document. 248 See Section 4 for information about defining new Proxy Status Types. 250 3.1. DNS Timeout 252 o Name: dns_timeout 254 o Description: The intermediary encountered a timeout when trying to 255 find an IP address for the destination hostname. 257 o Extra Parameters: None. 259 o Recommended HTTP status code: 504 261 3.2. DNS Error 263 o Name: dns_error 265 o Description: The intermediary encountered a DNS error when trying 266 to find an IP address for the destination hostname. 268 o Extra Parameters: 270 * rcode: A sh-string conveying the DNS RCODE that indicates the 271 error type. See [RFC8499], Section 3. 273 o Recommended HTTP status code: 502 275 3.3. Destination Not Found 277 o Name: destination_not_found 279 o Description: The intermediary cannot determine the appropriate 280 destination to use for this request; for example, it may not be 281 configured. Note that this error is specific to gateways, which 282 typically require specific configuration to identify the "backend" 283 server; forward proxies use in-band information to identify the 284 origin server. 286 o Extra Parameters: None. 288 o Recommended HTTP status code: 500 290 3.4. Destination Unavailable 292 o Name: destination_unavailable 294 o Description: The intermediary considers the next hop to be 295 unavailable; e.g., recent attempts to communicate with it may have 296 failed, or a health check may indicate that it is down. 298 o Extra Parameters: 300 o Recommended HTTP status code: 503 302 3.5. Destination IP Prohibited 304 o Name: destination_ip_prohibited 306 o Description: The intermediary is configured to prohibit 307 connections to the destination IP address. 309 o Extra Parameters: None. 311 o Recommended HTTP status code: 502 313 3.6. Destination IP Unroutable 315 o Name: destination_ip_unroutable 317 o Description: The intermediary cannot find a route to the 318 destination IP address. 320 o Extra Parameters: None. 322 o Recommended HTTP status code: 502 324 3.7. Connection Refused 326 o Name: connection_refused 328 o Description: The intermediary's connection to the next hop was 329 refused. 331 o Extra Parameters: None. 333 o Recommended HTTP status code: 502 335 3.8. Connection Terminated 337 o Name: connection_terminated 339 o Description: The intermediary's connection to the next hop was 340 closed before any part of the response was received. If some part 341 was received, see http_response_incomplete. 343 o Extra Parameters: None. 345 o Recommended HTTP status code: 502 347 3.9. Connection Timeout 349 o Name: connection_timeout 351 o Description: The intermediary's attempt to open a connection to 352 the next hop timed out. 354 o Extra Parameters: None. 356 o Recommended HTTP status code: 504 358 3.10. Connection Read Timeout 360 o Name: connection_read_timeout 362 o Description: The intermediary was expecting data on a connection 363 (e.g., part of a response), but did not receive any new data in a 364 configured time limit. 366 o Extra Parameters: None. 368 o Recommended HTTP status code: 504 370 3.11. Connection Write Timeout 372 o Name: connection_write_timeout 374 o Description: The intermediary was attempting to write data to a 375 connection, but was not able to (e.g., because its buffers were 376 full). 378 o Extra Parameters: None. 380 o Recommended HTTP status code: 504 382 3.12. Connection Limit Reached 384 o Name: connnection_limit_reached 386 o Description: The intermediary is configured to limit the number of 387 connections it has to the next hop, and that limit has been 388 passed. 390 o Extra Parameters: None. 392 o Recommended HTTP status code: 394 3.13. HTTP Response Status 396 o Name: http_response_status 398 o Description: The intermediary has received a 4xx or 5xx status 399 code from the next hop and forwarded it to the client. 401 o Extra Parameters: None. 403 o Recommended HTTP status code: 405 3.14. HTTP Incomplete Response 407 o Name: http_response_incomplete 409 o Description: The intermediary received an incomplete response to 410 the request from the next hop. 412 o Extra Parameters: None. 414 o Recommended HTTP status code: 502 416 3.15. HTTP Protocol Error 418 o Name: http_protocol_error 420 o Description: The intermediary encountered a HTTP protocol error 421 when communicating with the next hop. This error should only be 422 used when a more specific one is not defined. 424 o Extra Parameters: 426 * details: a sh-string containing details about the error 427 condition. For example, this might be the HTTP/2 error code or 428 free-form text describing the condition. 430 o Recommended HTTP status code: 502 432 3.16. HTTP Response Header Block Too Large 434 o Name: http_response_header_block_size 436 o Description: The intermediary received a response to the request 437 whose header block was considered too large. 439 o Extra Parameters: 441 * header_block_size: a sh-integer indicating how large the 442 headers received were. Note that they might not be complete; 443 i.e., the intermediary may have discarded or refused additional 444 data. 446 o Recommended HTTP status code: 502 448 3.17. HTTP Response Header Too Large 450 o Name: http_response_header_size 452 o Description: The intermediary received a response to the request 453 containing an individual header line that was considered too 454 large. 456 o Extra Parameters: 458 * header_name: a sh-string indicating the name of the header that 459 triggered the error. 461 o Recommended HTTP status code: 502 463 3.18. HTTP Response Body Too Large 465 o Name: http_response_body_size 467 o Description: The intermediary received a response to the request 468 whose body was considered too large. 470 o Extra Parameters: 472 * body_size: a sh-integer indicating how large the body received 473 was. Note that it may not have been complete; i.e., the 474 intermediary may have discarded or refused additional data. 476 o Recommended HTTP status code: 502 478 3.19. HTTP Response Transfer-Coding Error 480 o Name: http_response_transfer_coding 482 o Description: The intermediary encountered an error decoding the 483 transfer-coding of the response. 485 o Extra Parameters: 487 * coding: a sh-token containing the specific coding that caused 488 the error. 490 * details: a sh-string containing details about the error 491 condition. 493 o Recommended HTTP status code: 502 495 3.20. HTTP Response Content-Coding Error 497 o Name: http_response_content_coding 499 o Description: The intermediary encountered an error decoding the 500 content-coding of the response. 502 o Extra Parameters: 504 * coding: a sh-token containing the specific coding that caused 505 the error. 507 * details: a sh-string containing details about the error 508 condition. 510 o Recommended HTTP status code: 502 512 3.21. HTTP Response Timeout 514 o Name: http_response_timeout 516 o Description: The intermediary reached a configured time limit 517 waiting for the complete response. 519 o Extra Parameters: None. 521 o Recommended HTTP status code: 504 523 3.22. TLS Handshake Error 525 o Name: tls_handshake_error 527 o Description: The intermediary encountered an error during TLS 528 handshake with the next hop. 530 o Extra Parameters: 532 * alert_message: a sh-token containing the applicable description 533 string from the TLS Alerts registry. 535 o Recommended HTTP status code: 502 537 3.23. TLS Untrusted Peer Certificate 539 o Name: tls_untrusted_peer_certificate 541 o Description: The intermediary received untrusted peer certificate 542 during TLS handshake with the next hop. 544 o Extra Parameters: None. 546 o Recommended HTTP status code: 502 548 3.24. TLS Expired Peer Certificate 550 o Name: tls_expired_peer_certificate 552 o Description: The intermediary received expired peer certificate 553 during TLS handshake with the next hop. 555 o Extra Parameters: None. 557 o Recommended HTTP status code: 502 559 3.25. TLS Unexpected Peer Certificate 561 o Name: tls_unexpected_peer_certificate 563 o Description: The intermediary received unexpected peer certificate 564 (e.g., SPKI doesn't match) during TLS handshake with the next hop. 566 o Extra Parameters: 568 * details: a sh-string containing the checksum or SPKI of the 569 certificate received from the next hop. 571 o Recommended HTTP status code: 502 573 3.26. TLS Unexpected Peer Identity 575 o Name: tls_unexpected_peer_identity 577 o Description: The intermediary received peer certificate with 578 unexpected identity (e.g., Subject Alternative Name doesn't match) 579 during TLS handshake with the next hop. 581 o Extra Parameters: 583 * details: a sh-string containing the identity of the next hop. 585 o Recommended HTTP status code: 502 587 3.27. TLS Missing Proxy Certificate 589 o Name: tls_missing_proxy_certificate 591 o Description: The next hop requested client certificate from the 592 intermediary during TLS handshake, but it wasn't configured with 593 one. 595 o Extra Parameters: None. 597 o Recommended HTTP status code: 500 599 3.28. TLS Rejected Proxy Certificate 601 o Name: tls_rejected_proxy_certificate 603 o Description: The next hop rejected client certificate provided by 604 the intermediary during TLS handshake. 606 o Extra Parameters: None. 608 o Recommended HTTP status code: 500 610 3.29. TLS Error 612 o Name: tls_error 614 o Description: The intermediary encountered a TLS error when 615 communicating with the next hop. 617 o Extra Parameters: 619 * alert_message: a sh-token containing the applicable description 620 string from the TLS Alerts registry. 622 o Recommended HTTP status code: 502 624 3.30. HTTP Request Error 626 o Name: http_request_error 628 o Description: The intermediary is generating a client (4xx) 629 response on the origin's behalf. Applicable status codes include 630 (but are not limited to) 400, 403, 405, 406, 408, 411, 413, 414, 631 415, 416, 417, 429. This proxy status type helps distinguish 632 between responses generated by intermediaries from those generated 633 by the origin. 635 o Extra Parameters: None. 637 o Recommended HTTP status code: The applicable 4xx status code 639 3.31. HTTP Request Denied 641 o Name: http_request_denied 643 o Description: The intermediary rejected HTTP request based on its 644 configuration and/or policy settings. The request wasn't 645 forwarded to the next hop. 647 o Extra Parameters: None. 649 o Recommended HTTP status code: 400 651 3.32. HTTP Upgrade Failed 653 o Name: http_upgrade_failed 655 o Description: The HTTP Upgrade between the intermediary and the 656 next hop failed. 658 o Extra Parameters: None. 660 o Recommended HTTP status code: 502 662 3.33. Proxy Internal Error 664 o Name: proxy_internal_error 665 o Description: The intermediary encountered an internal error 666 unrelated to the origin. 668 o Extra Parameters: 670 * details: a sh-string containing details about the error 671 condition. 673 o Recommended HTTP status code: 500 675 4. Defining New Proxy Status Types 677 New Proxy Status Types can be defined by registering them in the HTTP 678 Proxy Status Types registry. 680 Registration requests are reviewed and approved by a Designated 681 Expert, as per [RFC8126] Section 4.5. A specification document is 682 appreciated, but not required. 684 The Expert(s) should consider the following factors when evaluating 685 requests: 687 o Community feedback 689 o If the value is sufficiently well-defined 691 o If the value is generic; vendor-specific, application-specific and 692 deployment-specific values are discouraged 694 Registration requests should use the following template: 696 o Name: [a name for the Proxy Status Type that is allowable as a sh- 697 param-list key] 699 o Description: [a description of the conditions that generate the 700 Proxy Status Types] 702 o Extra Parameters: [zero or more optional parameters, typed using 703 one of the types available in sh-item] 705 o Recommended HTTP status code: [the appropriate HTTP status code 706 for this entry] 708 See the registry at https://iana.org/assignments/http-proxy-statuses 709 [4] for details on where to send registration requests. 711 5. IANA Considerations 713 Upon publication, please create the HTTP Proxy Status Types registry 714 at https://iana.org/assignments/http-proxy-statuses [5] and populate 715 it with the types defined in Section 3; see Section 4 for its 716 associated procedures. 718 6. Security Considerations 720 One of the primary security concerns when using Proxy-Status is 721 leaking information that might aid an attacker. 723 As a result, care needs to be taken when deciding to generate a 724 Proxy-Status header. Note that intermediaries are not required to 725 generate a Proxy-Status header field in any response, and can 726 conditionally generate them based upon request attributes (e.g., 727 authentication tokens, IP address). 729 Likewise, generation of all parameters is optional. 731 Special care needs to be taken in generating proxy and origin 732 parameters, as they can expose information about the intermediary's 733 configuration and back-end topology. 735 7. References 737 7.1. Normative References 739 [I-D.ietf-httpbis-header-structure] 740 Nottingham, M. and P. Kamp, "Structured Headers for HTTP", 741 draft-ietf-httpbis-header-structure-09 (work in progress), 742 December 2018. 744 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 745 Requirement Levels", BCP 14, RFC 2119, 746 DOI 10.17487/RFC2119, March 1997, 747 . 749 [RFC7301] Friedl, S., Popov, A., Langley, A., and E. Stephan, 750 "Transport Layer Security (TLS) Application-Layer Protocol 751 Negotiation Extension", RFC 7301, DOI 10.17487/RFC7301, 752 July 2014, . 754 [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for 755 Writing an IANA Considerations Section in RFCs", BCP 26, 756 RFC 8126, DOI 10.17487/RFC8126, June 2017, 757 . 759 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 760 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 761 May 2017, . 763 [RFC8499] Hoffman, P., Sullivan, A., and K. Fujiwara, "DNS 764 Terminology", BCP 219, RFC 8499, DOI 10.17487/RFC8499, 765 January 2019, . 767 7.2. URIs 769 [1] https://github.com/mnot/I-D/labels/proxy-status 771 [2] https://mnot.github.io/I-D/proxy-status/ 773 [3] https://datatracker.ietf.org/doc/draft-nottingham-proxy-status/ 775 [4] https://iana.org/assignments/http-proxy-statuses 777 [5] https://iana.org/assignments/http-proxy-statuses 779 Authors' Addresses 781 Mark Nottingham 782 Fastly 784 Email: mnot@mnot.net 785 URI: https://www.mnot.net/ 787 Piotr Sikora 788 Google 790 Email: piotrsikora@google.com