{
    "content": [
        {
            "type": "text",
            "text": "# canonical (man)\n\n## NAME\n\ncanonical - Postfix canonical table format\n\n## DESCRIPTION\n\nThe  optional  canonical(5)  table  specifies  an address mapping for local and non-local ad‐\ndresses. The mapping is used by the cleanup(8) daemon, before mail is stored into the  queue.\nThe address mapping is recursive.\n\n## Sections\n\n- **NAME**\n- **SYNOPSIS** (1 subsections)\n- **DESCRIPTION**\n- **CASE FOLDING**\n- **TABLE FORMAT**\n- **TABLE SEARCH ORDER**\n- **RESULT ADDRESS REWRITING**\n- **ADDRESS EXTENSION**\n- **REGULAR EXPRESSION TABLES**\n- **TCP-BASED TABLES**\n- **BUGS**\n- **CONFIGURATION PARAMETERS** (15 subsections)\n- **SEE ALSO**\n- **README FILES**\n- **LICENSE**\n\nUse structuredContent.sections for detailed options, examples, and full documentation.\n"
        }
    ],
    "structuredContent": {
        "command": "canonical",
        "section": "",
        "mode": "man",
        "summary": "canonical - Postfix canonical table format",
        "synopsis": "",
        "tldr_summary": null,
        "tldr_examples": [],
        "tldr_source": null,
        "flags": [],
        "examples": [],
        "see_also": [
            {
                "name": "cleanup",
                "section": "8",
                "url": "https://www.chedong.com/phpMan.php/man/cleanup/8/json"
            },
            {
                "name": "postmap",
                "section": "1",
                "url": "https://www.chedong.com/phpMan.php/man/postmap/1/json"
            },
            {
                "name": "postconf",
                "section": "5",
                "url": "https://www.chedong.com/phpMan.php/man/postconf/5/json"
            },
            {
                "name": "virtual",
                "section": "5",
                "url": "https://www.chedong.com/phpMan.php/man/virtual/5/json"
            }
        ],
        "section_outline": [
            {
                "name": "NAME",
                "lines": 2,
                "subsections": []
            },
            {
                "name": "SYNOPSIS",
                "lines": 1,
                "subsections": [
                    {
                        "name": "postmap /etc/postfix/canonical",
                        "lines": 4
                    }
                ]
            },
            {
                "name": "DESCRIPTION",
                "lines": 33,
                "subsections": []
            },
            {
                "name": "CASE FOLDING",
                "lines": 4,
                "subsections": []
            },
            {
                "name": "TABLE FORMAT",
                "lines": 13,
                "subsections": []
            },
            {
                "name": "TABLE SEARCH ORDER",
                "lines": 42,
                "subsections": []
            },
            {
                "name": "RESULT ADDRESS REWRITING",
                "lines": 9,
                "subsections": []
            },
            {
                "name": "ADDRESS EXTENSION",
                "lines": 6,
                "subsections": []
            },
            {
                "name": "REGULAR EXPRESSION TABLES",
                "lines": 14,
                "subsections": []
            },
            {
                "name": "TCP-BASED TABLES",
                "lines": 10,
                "subsections": []
            },
            {
                "name": "BUGS",
                "lines": 2,
                "subsections": []
            },
            {
                "name": "CONFIGURATION PARAMETERS",
                "lines": 3,
                "subsections": [
                    {
                        "name": "canonical_classes (envelope_sender, envelope_recipient, header_sender, header_recipient)",
                        "lines": 2
                    },
                    {
                        "name": "canonical_maps (empty)",
                        "lines": 2
                    },
                    {
                        "name": "recipient_canonical_maps (empty)",
                        "lines": 2
                    },
                    {
                        "name": "sender_canonical_maps (empty)",
                        "lines": 2
                    },
                    {
                        "name": "propagate_unmatched_extensions (canonical, virtual)",
                        "lines": 5
                    },
                    {
                        "name": "inet_interfaces (all)",
                        "lines": 2
                    },
                    {
                        "name": "local_header_rewrite_clients (permit_inet_interfaces)",
                        "lines": 5
                    },
                    {
                        "name": "proxy_interfaces (empty)",
                        "lines": 3
                    },
                    {
                        "name": "masquerade_classes (envelope_sender, header_sender, header_recipient)",
                        "lines": 2
                    },
                    {
                        "name": "masquerade_domains (empty)",
                        "lines": 3
                    },
                    {
                        "name": "masquerade_exceptions (empty)",
                        "lines": 3
                    },
                    {
                        "name": "mydestination ($myhostname, localhost.$mydomain, localhost)",
                        "lines": 3
                    },
                    {
                        "name": "myorigin ($myhostname)",
                        "lines": 3
                    },
                    {
                        "name": "owner_request_special (yes)",
                        "lines": 4
                    },
                    {
                        "name": "remote_header_rewrite_domain (empty)",
                        "lines": 4
                    }
                ]
            },
            {
                "name": "SEE ALSO",
                "lines": 5,
                "subsections": []
            },
            {
                "name": "README FILES",
                "lines": 4,
                "subsections": []
            },
            {
                "name": "LICENSE",
                "lines": 14,
                "subsections": []
            }
        ],
        "sections": {
            "NAME": {
                "content": "canonical - Postfix canonical table format\n",
                "subsections": []
            },
            "SYNOPSIS": {
                "content": "",
                "subsections": [
                    {
                        "name": "postmap /etc/postfix/canonical",
                        "content": "postmap -q \"string\" /etc/postfix/canonical\n\npostmap -q - /etc/postfix/canonical <inputfile\n"
                    }
                ]
            },
            "DESCRIPTION": {
                "content": "The  optional  canonical(5)  table  specifies  an address mapping for local and non-local ad‐\ndresses. The mapping is used by the cleanup(8) daemon, before mail is stored into the  queue.\nThe address mapping is recursive.\n\nNormally,  the  canonical(5)  table  is  specified as a text file that serves as input to the\npostmap(1) command.  The result, an indexed file in dbm  or  db  format,  is  used  for  fast\nsearching by the mail system. Execute the command \"postmap /etc/postfix/canonical\" to rebuild\nan indexed file after changing the corresponding text file.\n\nWhen  the  table  is  provided via other means such as NIS, LDAP or SQL, the same lookups are\ndone as for ordinary indexed files.\n\nAlternatively, the table can be provided as a regular-expression map where patterns are given\nas regular expressions, or lookups can be directed to a TCP-based server. In those cases, the\nlookups are done in a slightly different way as described below under \"REGULAR EXPRESSION TA‐\nBLES\" or \"TCP-BASED TABLES\".\n\nBy default the canonical(5) mapping affects both message  header  addresses  (i.e.  addresses\nthat  appear inside messages) and message envelope addresses (for example, the addresses that\nare used in SMTP protocol commands). This is controlled with the canonicalclasses parameter.\n\nNOTE: Postfix versions 2.2 and later rewrite message headers from remote SMTP clients only if\nthe  client   matches   the   localheaderrewriteclients   parameter,   or   if   the   re‐\nmoteheaderrewritedomain  configuration  parameter  specifies a non-empty value. To get the\nbehavior before Postfix 2.2, specify \"localheaderrewriteclients = static:all\".\n\nTypically, one would use the canonical(5) table to replace login names by Firstname.Lastname,\nor to clean up addresses produced by legacy mail systems.\n\nThe canonical(5) mapping is not to be confused with  virtual  alias  support  or  with  local\naliasing. To change the destination but not the headers, use the virtual(5) or aliases(5) map\ninstead.\n",
                "subsections": []
            },
            "CASE FOLDING": {
                "content": "The  search  string  is  folded  to  lowercase before database lookup. As of Postfix 2.3, the\nsearch string is not case folded with database types such as regexp: or  pcre:  whose  lookup\nfields can match both upper and lower case.\n",
                "subsections": []
            },
            "TABLE FORMAT": {
                "content": "The input format for the postmap(1) command is as follows:\n\npattern address\nWhen pattern matches a mail address, replace it by the corresponding address.\n\nblank lines and comments\nEmpty lines and whitespace-only lines are ignored, as are lines whose first non-white‐\nspace character is a `#'.\n\nmulti-line text\nA  logical  line  starts  with non-whitespace text. A line that starts with whitespace\ncontinues a logical line.\n",
                "subsections": []
            },
            "TABLE SEARCH ORDER": {
                "content": "With lookups from indexed files such as DB or DBM, or from networked tables such as NIS, LDAP\nor SQL, each user@domain query produces a sequence of query patterns as described below.\n\nEach query pattern is sent to each specified lookup table before trying the next  query  pat‐\ntern, until a match is found.\n\nuser@domain address\nReplace user@domain by address. This form has the highest precedence.\n\nThis  is useful to clean up addresses produced by legacy mail systems.  It can also be\nused to produce Firstname.Lastname style addresses, but see below for a simpler  solu‐\ntion.\n\nuser address\nReplace  user@site  by address when site is equal to $myorigin, when site is listed in\n$mydestination, or when it is listed in $inetinterfaces or $proxyinterfaces.\n\nThis form is useful for replacing login names by Firstname.Lastname.\n\n@domain address\nReplace other addresses in domain by address.  This form has the lowest precedence.\n\nNote: @domain is a wild-card. When this form is applied to  recipient  addresses,  the\nPostfix  SMTP  server  accepts mail for any recipient in domain, regardless of whether\nthat recipient exists.  This may turn your mail  system  into  a  backscatter  source:\nPostfix  first  accepts mail for non-existent recipients and then tries to return that\nmail as \"undeliverable\" to the often forged sender address.\n\nTo avoid backscatter with mail for a wild-card domain, replace the  wild-card  mapping\nwith  explicit 1:1 mappings, or add a rejectunverifiedrecipient restriction for that\ndomain:\n\nsmtpdrecipientrestrictions =\n...\nrejectunauthdestination\ncheckrecipientaccess\ninline:{example.com=rejectunverifiedrecipient}\nunverifiedrecipientrejectcode = 550\n\nIn the above example, Postfix may contact a remote server if the recipient is  rewrit‐\nten to a remote address.\n",
                "subsections": []
            },
            "RESULT ADDRESS REWRITING": {
                "content": "The lookup result is subject to address rewriting:\n\n•      When  the result has the form @otherdomain, the result becomes the same user in other‐\ndomain.\n\n•      When \"appendatmyorigin=yes\", append \"@$myorigin\" to addresses without \"@domain\".\n\n•      When \"appenddotmydomain=yes\", append \".$mydomain\" to addresses without \".domain\".\n",
                "subsections": []
            },
            "ADDRESS EXTENSION": {
                "content": "When a mail address localpart contains the optional recipient delimiter  (e.g.,  user+foo@do‐\nmain), the lookup order becomes: user+foo@domain, user@domain, user+foo, user, and @domain.\n\nThe  propagateunmatchedextensions parameter controls whether an unmatched address extension\n(+foo) is propagated to the result of table lookup.\n",
                "subsections": []
            },
            "REGULAR EXPRESSION TABLES": {
                "content": "This section describes how the table lookups change when the table is given in  the  form  of\nregular  expressions.  For  a description of regular expression lookup table syntax, see reg‐\nexptable(5) or pcretable(5).\n\nEach pattern is a regular expression that is applied to the entire address being  looked  up.\nThus,  user@domain  mail  addresses are not broken up into their user and @domain constituent\nparts, nor is user+foo broken up into user and foo.\n\nPatterns are applied in the order as specified in the table, until a pattern  is  found  that\nmatches the search string.\n\nResults are the same as with indexed file lookups, with the additional feature that parenthe‐\nsized substrings from the pattern can be interpolated as $1, $2 and so on.\n",
                "subsections": []
            },
            "TCP-BASED TABLES": {
                "content": "This  section describes how the table lookups change when lookups are directed to a TCP-based\nserver. For a description of the TCP client/server lookup protocol, see  tcptable(5).   This\nfeature is not available up to and including Postfix version 2.4.\n\nEach lookup operation uses the entire address once.  Thus, user@domain mail addresses are not\nbroken  up into their user and @domain constituent parts, nor is user+foo broken up into user\nand foo.\n\nResults are the same as with indexed file lookups.\n",
                "subsections": []
            },
            "BUGS": {
                "content": "The table format does not understand quoting conventions.\n",
                "subsections": []
            },
            "CONFIGURATION PARAMETERS": {
                "content": "The following main.cf parameters are especially relevant.  The text below provides only a pa‐\nrameter summary. See postconf(5) for more details including examples.\n",
                "subsections": [
                    {
                        "name": "canonical_classes (envelope_sender, envelope_recipient, header_sender, header_recipient)",
                        "content": "What addresses are subject to canonicalmaps address mapping.\n"
                    },
                    {
                        "name": "canonical_maps (empty)",
                        "content": "Optional address mapping lookup tables for message headers and envelopes.\n"
                    },
                    {
                        "name": "recipient_canonical_maps (empty)",
                        "content": "Optional address mapping lookup tables for envelope and header recipient addresses.\n"
                    },
                    {
                        "name": "sender_canonical_maps (empty)",
                        "content": "Optional address mapping lookup tables for envelope and header sender addresses.\n"
                    },
                    {
                        "name": "propagate_unmatched_extensions (canonical, virtual)",
                        "content": "What address lookup tables copy an address extension from the lookup key to the lookup\nresult.\n\nOther parameters of interest:\n"
                    },
                    {
                        "name": "inet_interfaces (all)",
                        "content": "The network interface addresses that this mail system receives mail on.\n"
                    },
                    {
                        "name": "local_header_rewrite_clients (permit_inet_interfaces)",
                        "content": "Rewrite message header addresses in mail from these clients and update incomplete  ad‐\ndresses  with  the domain name in $myorigin or $mydomain; either don't rewrite message\nheaders from other clients at all, or rewrite message headers  and  update  incomplete\naddresses with the domain specified in the remoteheaderrewritedomain parameter.\n"
                    },
                    {
                        "name": "proxy_interfaces (empty)",
                        "content": "The  network  interface  addresses  that this mail system receives mail on by way of a\nproxy or network address translation unit.\n"
                    },
                    {
                        "name": "masquerade_classes (envelope_sender, header_sender, header_recipient)",
                        "content": "What addresses are subject to address masquerading.\n"
                    },
                    {
                        "name": "masquerade_domains (empty)",
                        "content": "Optional list of domains whose subdomain structure will be stripped off in  email  ad‐\ndresses.\n"
                    },
                    {
                        "name": "masquerade_exceptions (empty)",
                        "content": "Optional  list of user names that are not subjected to address masquerading, even when\ntheir addresses match $masqueradedomains.\n"
                    },
                    {
                        "name": "mydestination ($myhostname, localhost.$mydomain, localhost)",
                        "content": "The list of domains that are delivered via the $localtransport mail  delivery  trans‐\nport.\n"
                    },
                    {
                        "name": "myorigin ($myhostname)",
                        "content": "The domain name that locally-posted mail appears to come from, and that locally posted\nmail is delivered to.\n"
                    },
                    {
                        "name": "owner_request_special (yes)",
                        "content": "Enable  special treatment for owner-listname entries in the aliases(5) file, and don't\nsplit owner-listname and listname-request address localparts when the recipientdelim‐\niter is set to \"-\".\n"
                    },
                    {
                        "name": "remote_header_rewrite_domain (empty)",
                        "content": "Don't rewrite message headers from remote clients at all when this parameter is empty;\notherwise, rewrite message headers and append the specified domain name to  incomplete\naddresses.\n"
                    }
                ]
            },
            "SEE ALSO": {
                "content": "cleanup(8), canonicalize and enqueue mail\npostmap(1), Postfix lookup table manager\npostconf(5), configuration parameters\nvirtual(5), virtual aliasing\n",
                "subsections": []
            },
            "README FILES": {
                "content": "Use \"postconf readmedirectory\" or \"postconf htmldirectory\" to locate this information.\nDATABASEREADME, Postfix lookup table overview\nADDRESSREWRITINGREADME, address rewriting guide\n",
                "subsections": []
            },
            "LICENSE": {
                "content": "The Secure Mailer license must be distributed with this software.\n\nAUTHOR(S)\nWietse Venema\nIBM T.J. Watson Research\nP.O. Box 704\nYorktown Heights, NY 10598, USA\n\nWietse Venema\nGoogle, Inc.\n111 8th Avenue\nNew York, NY 10011, USA\n\nCANONICAL(5)",
                "subsections": []
            }
        }
    }
}