Table of Contents
1 Introduction.............................................7
1.1 Purpose ..............................................7
1.2 Requirements .........................................7
1.3 Terminology ..........................................8
1.4 Overall Operation ...................................11
2 Notational Conventions and Generic Grammar..............13
2.1 Augmented BNF .......................................13
2.2 Basic Rules .........................................15
3 Protocol Parameters.....................................17
3.1 HTTP Version ........................................17
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RFC 2068 HTTP/1.1 January 1997
3.2 Uniform Resource Identifiers ........................18
3.2.1 General Syntax ...................................18
3.2.2 http URL .........................................19
3.2.3 URI Comparison ...................................20
3.3 Date/Time Formats ...................................21
3.3.1 Full Date ........................................21
3.3.2 Delta Seconds ....................................22
3.4 Character Sets ......................................22
3.5 Content Codings .....................................23
3.6 Transfer Codings ....................................24
3.7 Media Types .........................................25
3.7.1 Canonicalization and Text Defaults ...............26
3.7.2 Multipart Types ..................................27
3.8 Product Tokens ......................................28
3.9 Quality Values ......................................28
3.10 Language Tags ......................................28
3.11 Entity Tags ........................................29
3.12 Range Units ........................................30
4 HTTP Message............................................30
4.1 Message Types .......................................30
4.2 Message Headers .....................................31
4.3 Message Body ........................................32
4.4 Message Length ......................................32
4.5 General Header Fields ...............................34
5 Request.................................................34
5.1 Request-Line ........................................34
5.1.1 Method ...........................................35
5.1.2 Request-URI ......................................35
5.2 The Resource Identified by a Request ................37
5.3 Request Header Fields ...............................37
6 Response................................................38
6.1 Status-Line .........................................38
6.1.1 Status Code and Reason Phrase ....................39
6.2 Response Header Fields ..............................41
7 Entity..................................................41
7.1 Entity Header Fields ................................41
7.2 Entity Body .........................................42
7.2.1 Type .............................................42
7.2.2 Length ...........................................43
8 Connections.............................................43
8.1 Persistent Connections ..............................43
8.1.1 Purpose ..........................................43
8.1.2 Overall Operation ................................44
8.1.3 Proxy Servers ....................................45
8.1.4 Practical Considerations .........................45
8.2 Message Transmission Requirements ...................46
9 Method Definitions......................................48
9.1 Safe and Idempotent Methods .........................48
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RFC 2068 HTTP/1.1 January 1997
9.1.1 Safe Methods .....................................48
9.1.2 Idempotent Methods ...............................49
9.2 OPTIONS .............................................49
9.3 GET .................................................50
9.4 HEAD ................................................50
9.5 POST ................................................51
9.6 PUT .................................................52
9.7 DELETE ..............................................53
9.8 TRACE ...............................................53
10 Status Code Definitions................................53
10.1 Informational 1xx ..................................54
10.1.1 100 Continue ....................................54
10.1.2 101 Switching Protocols .........................54
10.2 Successful 2xx .....................................54
10.2.1 200 OK ..........................................54
10.2.2 201 Created .....................................55
10.2.3 202 Accepted ....................................55
10.2.4 203 Non-Authoritative Information ...............55
10.2.5 204 No Content ..................................55
10.2.6 205 Reset Content ...............................56
10.2.7 206 Partial Content .............................56
10.3 Redirection 3xx ....................................56
10.3.1 300 Multiple Choices ............................57
10.3.2 301 Moved Permanently ...........................57
10.3.3 302 Moved Temporarily ...........................58
10.3.4 303 See Other ...................................58
10.3.5 304 Not Modified ................................58
10.3.6 305 Use Proxy ...................................59
10.4 Client Error 4xx ...................................59
10.4.1 400 Bad Request .................................60
10.4.2 401 Unauthorized ................................60
10.4.3 402 Payment Required ............................60
10.4.4 403 Forbidden ...................................60
10.4.5 404 Not Found ...................................60
10.4.6 405 Method Not Allowed ..........................61
10.4.7 406 Not Acceptable ..............................61
10.4.8 407 Proxy Authentication Required ...............61
10.4.9 408 Request Timeout .............................62
10.4.10 409 Conflict ...................................62
10.4.11 410 Gone .......................................62
10.4.12 411 Length Required ............................63
10.4.13 412 Precondition Failed ........................63
10.4.14 413 Request Entity Too Large ...................63
10.4.15 414 Request-URI Too Long .......................63
10.4.16 415 Unsupported Media Type .....................63
10.5 Server Error 5xx ...................................64
10.5.1 500 Internal Server Error .......................64
10.5.2 501 Not Implemented .............................64
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10.5.3 502 Bad Gateway .................................64
10.5.4 503 Service Unavailable .........................64
10.5.5 504 Gateway Timeout .............................64
10.5.6 505 HTTP Version Not Supported ..................65
11 Access Authentication..................................65
11.1 Basic Authentication Scheme ........................66
11.2 Digest Authentication Scheme .......................67
12 Content Negotiation....................................67
12.1 Server-driven Negotiation ..........................68
12.2 Agent-driven Negotiation ...........................69
12.3 Transparent Negotiation ............................70
13 Caching in HTTP........................................70
13.1.1 Cache Correctness ...............................72
13.1.2 Warnings ........................................73
13.1.3 Cache-control Mechanisms ........................74
13.1.4 Explicit User Agent Warnings ....................74
13.1.5 Exceptions to the Rules and Warnings ............75
13.1.6 Client-controlled Behavior ......................75
13.2 Expiration Model ...................................75
13.2.1 Server-Specified Expiration .....................75
13.2.2 Heuristic Expiration ............................76
13.2.3 Age Calculations ................................77
13.2.4 Expiration Calculations .........................79
13.2.5 Disambiguating Expiration Values ................80
13.2.6 Disambiguating Multiple Responses ...............80
13.3 Validation Model ...................................81
13.3.1 Last-modified Dates .............................82
13.3.2 Entity Tag Cache Validators .....................82
13.3.3 Weak and Strong Validators ......................82
13.3.4 Rules for When to Use Entity Tags and Last-
modified Dates..........................................85
13.3.5 Non-validating Conditionals .....................86
13.4 Response Cachability ...............................86
13.5 Constructing Responses From Caches .................87
13.5.1 End-to-end and Hop-by-hop Headers ...............88
13.5.2 Non-modifiable Headers ..........................88
13.5.3 Combining Headers ...............................89
13.5.4 Combining Byte Ranges ...........................90
13.6 Caching Negotiated Responses .......................90
13.7 Shared and Non-Shared Caches .......................91
13.8 Errors or Incomplete Response Cache Behavior .......91
13.9 Side Effects of GET and HEAD .......................92
13.10 Invalidation After Updates or Deletions ...........92
13.11 Write-Through Mandatory ...........................93
13.12 Cache Replacement .................................93
13.13 History Lists .....................................93
14 Header Field Definitions...............................94
14.1 Accept .............................................95
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14.2 Accept-Charset .....................................97
14.3 Accept-Encoding ....................................97
14.4 Accept-Language ....................................98
14.5 Accept-Ranges ......................................99
14.6 Age ................................................99
14.7 Allow .............................................100
14.8 Authorization .....................................100
14.9 Cache-Control .....................................101
14.9.1 What is Cachable ...............................103
14.9.2 What May be Stored by Caches ...................103
14.9.3 Modifications of the Basic Expiration Mechanism 104
14.9.4 Cache Revalidation and Reload Controls .........105
14.9.5 No-Transform Directive .........................107
14.9.6 Cache Control Extensions .......................108
14.10 Connection .......................................109
14.11 Content-Base .....................................109
14.12 Content-Encoding .................................110
14.13 Content-Language .................................110
14.14 Content-Length ...................................111
14.15 Content-Location .................................112
14.16 Content-MD5 ......................................113
14.17 Content-Range ....................................114
14.18 Content-Type .....................................116
14.19 Date .............................................116
14.20 ETag .............................................117
14.21 Expires ..........................................117
14.22 From .............................................118
14.23 Host .............................................119
14.24 If-Modified-Since ................................119
14.25 If-Match .........................................121
14.26 If-None-Match ....................................122
14.27 If-Range .........................................123
14.28 If-Unmodified-Since ..............................124
14.29 Last-Modified ....................................124
14.30 Location .........................................125
14.31 Max-Forwards .....................................125
14.32 Pragma ...........................................126
14.33 Proxy-Authenticate ...............................127
14.34 Proxy-Authorization ..............................127
14.35 Public ...........................................127
14.36 Range ............................................128
14.36.1 Byte Ranges ...................................128
14.36.2 Range Retrieval Requests ......................130
14.37 Referer ..........................................131
14.38 Retry-After ......................................131
14.39 Server ...........................................132
14.40 Transfer-Encoding ................................132
14.41 Upgrade ..........................................132
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14.42 User-Agent .......................................134
14.43 Vary .............................................134
14.44 Via ..............................................135
14.45 Warning ..........................................137
14.46 WWW-Authenticate .................................139
15 Security Considerations...............................139
15.1 Authentication of Clients .........................139
15.2 Offering a Choice of Authentication Schemes .......140
15.3 Abuse of Server Log Information ...................141
15.4 Transfer of Sensitive Information .................141
15.5 Attacks Based On File and Path Names ..............142
15.6 Personal Information ..............................143
15.7 Privacy Issues Connected to Accept Headers ........143
15.8 DNS Spoofing ......................................144
15.9 Location Headers and Spoofing .....................144
16 Acknowledgments.......................................144
17 References............................................146
18 Authors' Addresses....................................149
19 Appendices............................................150
19.1 Internet Media Type message/http ..................150
19.2 Internet Media Type multipart/byteranges ..........150
19.3 Tolerant Applications .............................151
19.4 Differences Between HTTP Entities and
MIME Entities...........................................152
19.4.1 Conversion to Canonical Form ...................152
19.4.2 Conversion of Date Formats .....................153
19.4.3 Introduction of Content-Encoding ...............153
19.4.4 No Content-Transfer-Encoding ...................153
19.4.5 HTTP Header Fields in Multipart Body-Parts .....153
19.4.6 Introduction of Transfer-Encoding ..............154
19.4.7 MIME-Version ...................................154
19.5 Changes from HTTP/1.0 .............................154
19.5.1 Changes to Simplify Multi-homed Web Servers and
Conserve IP Addresses .................................155
19.6 Additional Features ...............................156
19.6.1 Additional Request Methods .....................156
19.6.2 Additional Header Field Definitions ............156
19.7 Compatibility with Previous Versions ..............160
19.7.1 Compatibility with HTTP/1.0 Persistent
Connections............................................161
目录
1 引论.............................................7
1.1 目的..............................................7
1.2 要求 .........................................7
1.3 术语 ..........................................8
1.4 总体操作 ...................................11
2 符号惯例和一般用法..............13
2.1 扩充BNF .......................................13
2.2 基本规则 .........................................15
3 协议参数 .....................................17
3.1 HTTP版本 ........................................17
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3.2 Uniform Resource Identifiers ........................18
3.2.1 General Syntax ...................................18
3.2.2 http URL .........................................19
3.2.3 URI Comparison ...................................20
3.3 Date/Time Formats ...................................21
3.3.1 Full Date ........................................21
3.3.2 Delta Seconds ....................................22
3.4 Character Sets ......................................22
3.5 Content Codings .....................................23
3.6 Transfer Codings ....................................24
3.7 Media Types .........................................25
3.7.1 Canonicalization and Text Defaults ...............26
3.7.2 Multipart Types ..................................27
3.8 Product Tokens ......................................28
3.9 Quality Values ......................................28
3.10 Language Tags ......................................28
3.11 Entity Tags ........................................29
3.12 Range Units ........................................30
4 HTTP Message............................................30
4.1 Message Types .......................................30
4.2 Message Headers .....................................31
4.3 Message Body ........................................32
4.4 Message Length ......................................32
4.5 General Header Fields ...............................34
5 Request.................................................34
5.1 Request-Line ........................................34
5.1.1 Method ...........................................35
5.1.2 Request-URI ......................................35
5.2 The Resource Identified by a Request ................37
5.3 Request Header Fields ...............................37
6 Response................................................38
6.1 Status-Line .........................................38
6.1.1 Status Code and Reason Phrase ....................39
6.2 Response Header Fields ..............................41
7 Entity..................................................41
7.1 Entity Header Fields ................................41
7.2 Entity Body .........................................42
7.2.1 Type .............................................42
7.2.2 Length ...........................................43
8 Connections.............................................43
8.1 Persistent Connections ..............................43
8.1.1 Purpose ..........................................43
8.1.2 Overall Operation ................................44
8.1.3 Proxy Servers ....................................45
8.1.4 Practical Considerations .........................45
8.2 Message Transmission Requirements ...................46
9 Method Definitions......................................48
9.1 Safe and Idempotent Methods .........................48
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RFC 2068 HTTP/1.1 January 1997
9.1.1 Safe Methods .....................................48
9.1.2 Idempotent Methods ...............................49
9.2 OPTIONS .............................................49
9.3 GET .................................................50
9.4 HEAD ................................................50
9.5 POST ................................................51
9.6 PUT .................................................52
9.7 DELETE ..............................................53
9.8 TRACE ...............................................53
10 Status Code Definitions................................53
10.1 Informational 1xx ..................................54
10.1.1 100 Continue ....................................54
10.1.2 101 Switching Protocols .........................54
10.2 Successful 2xx .....................................54
10.2.1 200 OK ..........................................54
10.2.2 201 Created .....................................55
10.2.3 202 Accepted ....................................55
10.2.4 203 Non-Authoritative Information ...............55
10.2.5 204 No Content ..................................55
10.2.6 205 Reset Content ...............................56
10.2.7 206 Partial Content .............................56
10.3 Redirection 3xx ....................................56
10.3.1 300 Multiple Choices ............................57
10.3.2 301 Moved Permanently ...........................57
10.3.3 302 Moved Temporarily ...........................58
10.3.4 303 See Other ...................................58
10.3.5 304 Not Modified ................................58
10.3.6 305 Use Proxy ...................................59
10.4 Client Error 4xx ...................................59
10.4.1 400 Bad Request .................................60
10.4.2 401 Unauthorized ................................60
10.4.3 402 Payment Required ............................60
10.4.4 403 Forbidden ...................................60
10.4.5 404 Not Found ...................................60
10.4.6 405 Method Not Allowed ..........................61
10.4.7 406 Not Acceptable ..............................61
10.4.8 407 Proxy Authentication Required ...............61
10.4.9 408 Request Timeout .............................62
10.4.10 409 Conflict ...................................62
10.4.11 410 Gone .......................................62
10.4.12 411 Length Required ............................63
10.4.13 412 Precondition Failed ........................63
10.4.14 413 Request Entity Too Large ...................63
10.4.15 414 Request-URI Too Long .......................63
10.4.16 415 Unsupported Media Type .....................63
10.5 Server Error 5xx ...................................64
10.5.1 500 Internal Server Error .......................64
10.5.2 501 Not Implemented .............................64
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10.5.3 502 Bad Gateway .................................64
10.5.4 503 Service Unavailable .........................64
10.5.5 504 Gateway Timeout .............................64
10.5.6 505 HTTP Version Not Supported ..................65
11 Access Authentication..................................65
11.1 Basic Authentication Scheme ........................66
11.2 Digest Authentication Scheme .......................67
12 Content Negotiation....................................67
12.1 Server-driven Negotiation ..........................68
12.2 Agent-driven Negotiation ...........................69
12.3 Transparent Negotiation ............................70
13 Caching in HTTP........................................70
13.1.1 Cache Correctness ...............................72
13.1.2 Warnings ........................................73
13.1.3 Cache-control Mechanisms ........................74
13.1.4 Explicit User Agent Warnings ....................74
13.1.5 Exceptions to the Rules and Warnings ............75
13.1.6 Client-controlled Behavior ......................75
13.2 Expiration Model ...................................75
13.2.1 Server-Specified Expiration .....................75
13.2.2 Heuristic Expiration ............................76
13.2.3 Age Calculations ................................77
13.2.4 Expiration Calculations .........................79
13.2.5 Disambiguating Expiration Values ................80
13.2.6 Disambiguating Multiple Responses ...............80
13.3 Validation Model ...................................81
13.3.1 Last-modified Dates .............................82
13.3.2 Entity Tag Cache Validators .....................82
13.3.3 Weak and Strong Validators ......................82
13.3.4 Rules for When to Use Entity Tags and Last-
modified Dates..........................................85
13.3.5 Non-validating Conditionals .....................86
13.4 Response Cachability ...............................86
13.5 Constructing Responses From Caches .................87
13.5.1 End-to-end and Hop-by-hop Headers ...............88
13.5.2 Non-modifiable Headers ..........................88
13.5.3 Combining Headers ...............................89
13.5.4 Combining Byte Ranges ...........................90
13.6 Caching Negotiated Responses .......................90
13.7 Shared and Non-Shared Caches .......................91
13.8 Errors or Incomplete Response Cache Behavior .......91
13.9 Side Effects of GET and HEAD .......................92
13.10 Invalidation After Updates or Deletions ...........92
13.11 Write-Through Mandatory ...........................93
13.12 Cache Replacement .................................93
13.13 History Lists .....................................93
14 Header Field Definitions...............................94
14.1 Accept .............................................95
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14.2 Accept-Charset .....................................97
14.3 Accept-Encoding ....................................97
14.4 Accept-Language ....................................98
14.5 Accept-Ranges ......................................99
14.6 Age ................................................99
14.7 Allow .............................................100
14.8 Authorization .....................................100
14.9 Cache-Control .....................................101
14.9.1 What is Cachable ...............................103
14.9.2 What May be Stored by Caches ...................103
14.9.3 Modifications of the Basic Expiration Mechanism 104
14.9.4 Cache Revalidation and Reload Controls .........105
14.9.5 No-Transform Directive .........................107
14.9.6 Cache Control Extensions .......................108
14.10 Connection .......................................109
14.11 Content-Base .....................................109
14.12 Content-Encoding .................................110
14.13 Content-Language .................................110
14.14 Content-Length ...................................111
14.15 Content-Location .................................112
14.16 Content-MD5 ......................................113
14.17 Content-Range ....................................114
14.18 Content-Type .....................................116
14.19 Date .............................................116
14.20 ETag .............................................117
14.21 Expires ..........................................117
14.22 From .............................................118
14.23 Host .............................................119
14.24 If-Modified-Since ................................119
14.25 If-Match .........................................121
14.26 If-None-Match ....................................122
14.27 If-Range .........................................123
14.28 If-Unmodified-Since ..............................124
14.29 Last-Modified ....................................124
14.30 Location .........................................125
14.31 Max-Forwards .....................................125
14.32 Pragma ...........................................126
14.33 Proxy-Authenticate ...............................127
14.34 Proxy-Authorization ..............................127
14.35 Public ...........................................127
14.36 Range ............................................128
14.36.1 Byte Ranges ...................................128
14.36.2 Range Retrieval Requests ......................130
14.37 Referer ..........................................131
14.38 Retry-After ......................................131
14.39 Server ...........................................132
14.40 Transfer-Encoding ................................132
14.41 Upgrade ..........................................132
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14.42 User-Agent .......................................134
14.43 Vary .............................................134
14.44 Via ..............................................135
14.45 Warning ..........................................137
14.46 WWW-Authenticate .................................139
15 Security Considerations...............................139
15.1 Authentication of Clients .........................139
15.2 Offering a Choice of Authentication Schemes .......140
15.3 Abuse of Server Log Information ...................141
15.4 Transfer of Sensitive Information .................141
15.5 Attacks Based On File and Path Names ..............142
15.6 Personal Information ..............................143
15.7 Privacy Issues Connected to Accept Headers ........143
15.8 DNS Spoofing ......................................144
15.9 Location Headers and Spoofing .....................144
16 Acknowledgments.......................................144
17 References............................................146
18 Authors' Addresses....................................149
19 Appendices............................................150
19.1 Internet Media Type message/http ..................150
19.2 Internet Media Type multipart/byteranges ..........150
19.3 Tolerant Applications .............................151
19.4 Differences Between HTTP Entities and
MIME Entities...........................................152
19.4.1 Conversion to Canonical Form ...................152
19.4.2 Conversion of Date Formats .....................153
19.4.3 Introduction of Content-Encoding ...............153
19.4.4 No Content-Transfer-Encoding ...................153
19.4.5 HTTP Header Fields in Multipart Body-Parts .....153
19.4.6 Introduction of Transfer-Encoding ..............154
19.4.7 MIME-Version ...................................154
19.5 Changes from HTTP/1.0 .............................154
19.5.1 Changes to Simplify Multi-homed Web Servers and
Conserve IP Addresses .................................155
19.6 Additional Features ...............................156
19.6.1 Additional Request Methods .....................156
19.6.2 Additional Header Field Definitions ............156
19.7 Compatibility with Previous Versions ..............160
19.7.1 Compatibility with HTTP/1.0 Persistent
Connections............................................161