{"Entry":{"collection":"protocol","key":"authenticationmd5password-b","name":"AuthenticationMD5Password","aliases":["AuthenticationMD5Password","Byte1('R')"],"metadata":{"aliases":["AuthenticationMD5Password","Byte1('R')"],"category":"Backend messages","content_hash":"0cd3e47266cf87553c44283748196489400c33df76aabe330af113e26fca7744","derived_content_hash":"9fee1c9d8200d1f5280104695e3f0d9845d3f6ab882e3fe999c8b3ed92f4e1f9","imported_at":"2026-09-30T00:40:44.411288+08:00","name":"AuthenticationMD5Password","name_zh":"","slug":"authenticationmd5password-b","summary":"AuthenticationMD5Password is a backend protocol message. Identifies the message as an authentication request."}},"Definition":{"Collection":"protocol","Key":"authenticationmd5password-b","SourceDatabase":"center","Version":"18","SourceTable":"protocol_message","SourceKey":"authenticationmd5password-b","SourceRevision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","Facts":{"comparison_data":{"direction":"B","fields":[{"description":"Identifies the message as an authentication request.","format":"Byte1('R')"},{"description":"Length of message contents in bytes, including self.","format":"Int32(12)"},{"description":"Specifies that an MD5-encrypted password is required.","format":"Int32(5)"},{"description":"The salt to use when encrypting the password.","format":"Byte4"}]},"comparison_hash":"f4b0a0c4c5091293fbc74f31e4f3b8435cca26b55168b64ffcc7401066af2275","description":["AuthenticationMD5Password is a backend protocol message. 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A numbered table row is a documented field definition, not a fixed byte offset. Integer encodings and flow rules follow the same-version protocol chapter."],"title":"Framing and repetition"}],"sections_zh":[{"paragraphs":["下方完整定义保留重复项、计数与条件字段。表格行号表示文档中的字段定义，并非固定字节偏移量。整数编码与交互流程以同版本协议章节为准。"],"title":"消息边界与重复字段"}],"signature":"AuthenticationMD5Password (B)","sources":[{"label":"PostgreSQL 18 English manual","path":"protocol-message-formats.html","sha256":"53f37652ac2c089e30ada87d8aee7bdd0f26695b03f275302e526a807d2a1f23","url":"/docs/18/protocol-message-formats.html#PROTOCOL-MESSAGE-FORMATS-AUTHENTICATIONMD5PASSWORD"}],"tables":[{"columns":[{"key":"c0","label":"Position"},{"key":"c1","label":"Format"},{"key":"c2","label":"Meaning"}],"key":"fields","rows":[{"c0":"1","c1":"Byte1('R')","c2":"Identifies the message as an authentication request."},{"c0":"2","c1":"Int32(12)","c2":"Length of message contents in bytes, including self."},{"c0":"3","c1":"Int32(5)","c2":"Specifies that an MD5-encrypted password is required."},{"c0":"4","c1":"Byte4","c2":"The salt to use when encrypting the password."}],"title":"Wire fields in documented order"}],"tables_zh":[{"columns":[{"key":"c0","label":"位置"},{"key":"c1","label":"格式"},{"key":"c2","label":"含义"}],"key":"fields","rows":[{"c0":"1","c1":"Byte1('R')","c2":"将该消息标识为认证请求。"},{"c0":"2","c1":"Int32(12)","c2":"消息内容的长度（以字节为单位），包括其自身。"},{"c0":"3","c1":"Int32(5)","c2":"表示需要经过 MD5 加密的密码。"},{"c0":"4","c1":"Byte4","c2":"加密密码时使用的盐。"}],"title":"按手册顺序排列的线上协议字段"}],"zh_from":{"authored_translation":"source-derived-identity","body_sha256":"3579060801d3163e4f9fe96b690a9833f01e6e3c0f167e809e56b25013d60e62","kind":"same-version-chinese-manual-with-source-derived-identity","manual":{"anchor":"PROTOCOL-MESSAGE-FORMATS-AUTHENTICATIONMD5PASSWORD","build_id":107,"extraction":"exact-definition","fragment_sha256":"077ad444a1d8497f3a242964b40278fcbe6e7dda0ccd2f56563632661714facb","locale":"zh-Hans","page_key":"protocol-message-formats.html","source_hash":"0be0a37b38d80c96c157ca9fcfe9222995654664aad8136f7ac2b1b552f6753a","source_revision":"unknown:rendered-translation-baseline","translated_from_revision":null,"translation_revision":"git:b1b500221dbe5437cfca004d6b04d3f6e422765d;html-sha256:08e987a66af27b98444a8057c256314eafa13611a3fb9e888214fc436824244b","url":"/zh/docs/18/protocol-message-formats.html#PROTOCOL-MESSAGE-FORMATS-AUTHENTICATIONMD5PASSWORD","version":"18"},"runtime_rerun":false,"source_facts_revision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}},"ManualEvidence":{"manual_path":"/docs/18/protocol-message-formats.html","release":{"channel":"stable","label":"18.6","major":"18","ref":"https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2","revision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"},"sources":[{"label":"PostgreSQL 18 English manual","path":"protocol-message-formats.html","sha256":"53f37652ac2c089e30ada87d8aee7bdd0f26695b03f275302e526a807d2a1f23","url":"/docs/18/protocol-message-formats.html#PROTOCOL-MESSAGE-FORMATS-AUTHENTICATIONMD5PASSWORD"}]},"MeasuredEvidence":{}},"Text":{"Collection":"protocol","Key":"authenticationmd5password-b","SourceDatabase":"center","Version":"18","Locale":"en","Title":"AuthenticationMD5Password","Summary":"AuthenticationMD5Password is a backend protocol message. Identifies the message as an authentication request.","BodyHTML":"\u003cdl\u003e\u003cdd\u003e\n\u003cdiv\u003e\n\u003cdl\u003e\n\u003cdt\u003e\u003cspan\u003eByte1(\u0026#39;R\u0026#39;)\u003c/span\u003e\u003c/dt\u003e\n\u003cdd\u003e\n\u003cp\u003eIdentifies the message as an authentication request.\u003c/p\u003e\n\u003c/dd\u003e\n\u003cdt\u003e\u003cspan\u003eInt32(12)\u003c/span\u003e\u003c/dt\u003e\n\u003cdd\u003e\n\u003cp\u003eLength of message contents in bytes, including self.\u003c/p\u003e\n\u003c/dd\u003e\n\u003cdt\u003e\u003cspan\u003eInt32(5)\u003c/span\u003e\u003c/dt\u003e\n\u003cdd\u003e\n\u003cp\u003eSpecifies that an MD5-encrypted password is required.\u003c/p\u003e\n\u003c/dd\u003e\n\u003cdt\u003e\u003cspan\u003eByte4\u003c/span\u003e\u003c/dt\u003e\n\u003cdd\u003e\n\u003cp\u003eThe salt to use when encrypting the password.\u003c/p\u003e\n\u003c/dd\u003e\n\u003c/dl\u003e\n\u003c/div\u003e\n\u003c/dd\u003e\u003c/dl\u003e","SourceRevision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","ContentHash":"d0fc0301689a90fd7157b43043266dda7f9ae689ebdc38fc077bdafa32a5f657","Payload":{"description":["AuthenticationMD5Password is a backend protocol message. 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