external/ibm-public/postfix/dist/src/global/header_opts.c

   1 /*      $NetBSD$        */
   2
   3 /*++
   4 /* NAME
   5 /*      header_opts 3
   6 /* SUMMARY
   7 /*      message header classification
   8 /* SYNOPSIS
   9 /*      #include <header_opts.h>
  10 /*
  11 /*      const HEADER_OPTS *header_opts_find(string)
  12 /*      const char *string;
  13 /* DESCRIPTION
  14 /*      header_opts_find() takes a message header line and looks up control
  15 /*      information for the corresponding header type.
  16 /* DIAGNOSTICS
  17 /*      Panic: input is not a valid header line. The result is a pointer
  18 /*      to HEADER_OPTS in case of success, a null pointer when the header
  19 /*      label was not recognized.
  20 /* SEE ALSO
  21 /*      header_opts(3h) the gory details
  22 /* LICENSE
  23 /* .ad
  24 /* .fi
  25 /*      The Secure Mailer license must be distributed with this software.
  26 /* AUTHOR(S)
  27 /*      Wietse Venema
  28 /*      IBM T.J. Watson Research
  29 /*      P.O. Box 704
  30 /*      Yorktown Heights, NY 10598, USA
  31 /*--*/
  32
  33 /* System library. */
  34
  35 #include <sys_defs.h>
  36 #include <ctype.h>
  37
  38 /* Utility library. */
  39
  40 #include <msg.h>
  41 #include <htable.h>
  42 #include <vstring.h>
  43 #include <stringops.h>
  44
  45 /* Global library. */
  46
  47 #include "header_opts.h"
  48
  49  /*
  50   * Header names are given in the preferred capitalization. The lookups are
  51   * case-insensitive.
  52   *
  53   * XXX Removing Return-Path: headers should probably be done only with mail
  54   * that enters via a non-SMTP channel. Changing this now could break other
  55   * software. See also comments in bounce_notify_util.c.
  56   */
  57 static const HEADER_OPTS header_opts[] = {
  58     "Apparently-To", HDR_APPARENTLY_TO, HDR_OPT_RECIP,
  59     "Bcc", HDR_BCC, HDR_OPT_DROP | HDR_OPT_XRECIP,
  60     "Cc", HDR_CC, HDR_OPT_XRECIP,
  61     "Content-Description", HDR_CONTENT_DESCRIPTION, HDR_OPT_MIME,
  62     "Content-Disposition", HDR_CONTENT_DISPOSITION, HDR_OPT_MIME,
  63     "Content-ID", HDR_CONTENT_ID, HDR_OPT_MIME,
  64     "Content-Length", HDR_CONTENT_LENGTH, HDR_OPT_DROP,
  65     "Content-Transfer-Encoding", HDR_CONTENT_TRANSFER_ENCODING, HDR_OPT_MIME,
  66     "Content-Type", HDR_CONTENT_TYPE, HDR_OPT_MIME,
  67     "Delivered-To", HDR_DELIVERED_TO, 0,
  68     "Disposition-Notification-To", HDR_DISP_NOTIFICATION, HDR_OPT_SENDER,
  69     "Date", HDR_DATE, 0,
  70     "Errors-To", HDR_ERRORS_TO, HDR_OPT_SENDER,
  71     "From", HDR_FROM, HDR_OPT_SENDER,
  72     "Mail-Followup-To", HDR_MAIL_FOLLOWUP_TO, HDR_OPT_SENDER,
  73     "Message-Id", HDR_MESSAGE_ID, 0,
  74     "MIME-Version", HDR_MIME_VERSION, HDR_OPT_MIME,
  75     "Received", HDR_RECEIVED, 0,
  76     "Reply-To", HDR_REPLY_TO, HDR_OPT_SENDER,
  77     "Resent-Bcc", HDR_RESENT_BCC, HDR_OPT_DROP | HDR_OPT_XRECIP | HDR_OPT_RR,
  78     "Resent-Cc", HDR_RESENT_CC, HDR_OPT_XRECIP | HDR_OPT_RR,
  79     "Resent-Date", HDR_RESENT_DATE, HDR_OPT_RR,
  80     "Resent-From", HDR_RESENT_FROM, HDR_OPT_SENDER | HDR_OPT_RR,
  81     "Resent-Message-Id", HDR_RESENT_MESSAGE_ID, HDR_OPT_RR,
  82     "Resent-Reply-To", HDR_RESENT_REPLY_TO, HDR_OPT_RECIP | HDR_OPT_RR,
  83     "Resent-Sender", HDR_RESENT_SENDER, HDR_OPT_SENDER | HDR_OPT_RR,
  84     "Resent-To", HDR_RESENT_TO, HDR_OPT_XRECIP | HDR_OPT_RR,
  85     "Return-Path", HDR_RETURN_PATH, HDR_OPT_DROP | HDR_OPT_SENDER,
  86     "Return-Receipt-To", HDR_RETURN_RECEIPT_TO, HDR_OPT_SENDER,
  87     "Sender", HDR_SENDER, HDR_OPT_SENDER,
  88     "To", HDR_TO, HDR_OPT_XRECIP,
  89 };
  90
  91 #define HEADER_OPTS_SIZE (sizeof(header_opts) / sizeof(header_opts[0]))
  92
  93 static HTABLE *header_hash;             /* quick lookup */
  94 static VSTRING *header_key;
  95
  96 /* header_opts_init - initialize */
  97
  98 static void header_opts_init(void)
  99 {
 100     const HEADER_OPTS *hp;
 101     const char *cp;
 102
 103     /*
 104      * Build a hash table for quick lookup, and allocate memory for
 105      * lower-casing the lookup key.
 106      */
 107     header_key = vstring_alloc(10);
 108     header_hash = htable_create(HEADER_OPTS_SIZE);
 109     for (hp = header_opts; hp < header_opts + HEADER_OPTS_SIZE; hp++) {
 110         VSTRING_RESET(header_key);
 111         for (cp = hp->name; *cp; cp++)
 112             VSTRING_ADDCH(header_key, TOLOWER(*cp));
 113         VSTRING_TERMINATE(header_key);
 114         htable_enter(header_hash, vstring_str(header_key), (char *) hp);
 115     }
 116 }
 117
 118 /* header_opts_find - look up header options */
 119
 120 const HEADER_OPTS *header_opts_find(const char *string)
 121 {
 122     const char *cp;
 123
 124     if (header_hash == 0)
 125         header_opts_init();
 126
 127     /*
 128      * Look up the lower-cased version of the header name.
 129      */
 130     VSTRING_RESET(header_key);
 131     for (cp = string; *cp != ':'; cp++) {
 132         if (*cp == 0)
 133             msg_panic("header_opts_find: no colon in header: %.30s", string);
 134         VSTRING_ADDCH(header_key, TOLOWER(*cp));
 135     }
 136     vstring_truncate(header_key,
 137                      trimblanks(vstring_str(header_key), cp - string)
 138                      - vstring_str(header_key));
 139     VSTRING_TERMINATE(header_key);
 140     return ((const HEADER_OPTS *) htable_find(header_hash, vstring_str(header_key)));
 141 }