external/ibm-public/postfix/dist/src/local/file.c

   1 /*      $NetBSD$        */
   2
   3 /*++
   4 /* NAME
   5 /*      file 3
   6 /* SUMMARY
   7 /*      mail delivery to arbitrary file
   8 /* SYNOPSIS
   9 /*      #include "local.h"
  10 /*
  11 /*      int     deliver_file(state, usr_attr, path)
  12 /*      LOCAL_STATE state;
  13 /*      USER_ATTR usr_attr;
  14 /*      char    *path;
  15 /* DESCRIPTION
  16 /*      deliver_file() appends a message to a file, UNIX mailbox format,
  17 /*      or qmail maildir format,
  18 /*      with duplicate suppression. It will deliver only to non-executable
  19 /*      regular files.
  20 /*
  21 /*      Arguments:
  22 /* .IP state
  23 /*      The attributes that specify the message, recipient and more.
  24 /*      Attributes describing alias, include or forward expansion.
  25 /*      A table with the results from expanding aliases or lists.
  26 /* .IP usr_attr
  27 /*      Attributes describing user rights and environment information.
  28 /* .IP path
  29 /*      The file to deliver to. If the name ends in '/', delivery is done
  30 /*      in qmail maildir format, otherwise delivery is done in UNIX mailbox
  31 /*      format.
  32 /* DIAGNOSTICS
  33 /*      deliver_file() returns non-zero when delivery should be tried again.
  34 /* SEE ALSO
  35 /*      defer(3)
  36 /*      bounce(3)
  37 /* LICENSE
  38 /* .ad
  39 /* .fi
  40 /*      The Secure Mailer license must be distributed with this software.
  41 /* AUTHOR(S)
  42 /*      Wietse Venema
  43 /*      IBM T.J. Watson Research
  44 /*      P.O. Box 704
  45 /*      Yorktown Heights, NY 10598, USA
  46 /*--*/
  47
  48 /* System library. */
  49
  50 #include <sys_defs.h>
  51 #include <sys/stat.h>
  52 #include <unistd.h>
  53 #include <fcntl.h>
  54 #include <errno.h>
  55 #include <string.h>
  56
  57 /* Utility library. */
  58
  59 #include <msg.h>
  60 #include <htable.h>
  61 #include <vstring.h>
  62 #include <vstream.h>
  63 #include <deliver_flock.h>
  64 #include <set_eugid.h>
  65
  66 /* Global library. */
  67
  68 #include <mail_copy.h>
  69 #include <bounce.h>
  70 #include <defer.h>
  71 #include <sent.h>
  72 #include <been_here.h>
  73 #include <mail_params.h>
  74 #include <mbox_conf.h>
  75 #include <mbox_open.h>
  76 #include <dsn_util.h>
  77
  78 /* Application-specific. */
  79
  80 #include "local.h"
  81
  82 /* deliver_file - deliver to file */
  83
  84 int     deliver_file(LOCAL_STATE state, USER_ATTR usr_attr, char *path)
  85 {
  86     const char *myname = "deliver_file";
  87     struct stat st;
  88     MBOX   *mp;
  89     DSN_BUF *why = state.msg_attr.why;
  90     int     mail_copy_status = MAIL_COPY_STAT_WRITE;
  91     int     deliver_status;
  92     int     copy_flags;
  93
  94     /*
  95      * Make verbose logging easier to understand.
  96      */
  97     state.level++;
  98     if (msg_verbose)
  99         MSG_LOG_STATE(myname, state);
 100
 101     /*
 102      * DUPLICATE ELIMINATION
 103      *
 104      * Skip this file if it was already delivered to as this user.
 105      */
 106     if (been_here(state.dup_filter, "file %ld %s", (long) usr_attr.uid, path))
 107         return (0);
 108
 109     /*
 110      * DELIVERY POLICY
 111      *
 112      * Do we allow delivery to files?
 113      */
 114     if ((local_file_deliver_mask & state.msg_attr.exp_type) == 0) {
 115         dsb_simple(why, "5.7.1", "mail to file is restricted");
 116         return (bounce_append(BOUNCE_FLAGS(state.request),
 117                               BOUNCE_ATTR(state.msg_attr)));
 118     }
 119
 120     /*
 121      * Don't deliver trace-only requests.
 122      */
 123     if (DEL_REQ_TRACE_ONLY(state.request->flags)) {
 124         dsb_simple(why, "2.0.0", "delivers to file: %s", path);
 125         return (sent(BOUNCE_FLAGS(state.request),
 126                      SENT_ATTR(state.msg_attr)));
 127     }
 128
 129     /*
 130      * DELIVERY RIGHTS
 131      *
 132      * Use a default uid/gid when none are given.
 133      */
 134     if (usr_attr.uid == 0 && (usr_attr.uid = var_default_uid) == 0)
 135         msg_panic("privileged default user id");
 136     if (usr_attr.gid == 0 && (usr_attr.gid = var_default_gid) == 0)
 137         msg_panic("privileged default group id");
 138
 139     /*
 140      * If the name ends in /, use maildir-style delivery instead.
 141      */
 142     if (path[strlen(path) - 1] == '/')
 143         return (deliver_maildir(state, usr_attr, path));
 144
 145     /*
 146      * Deliver. From here on, no early returns or we have a memory leak.
 147      */
 148     if (msg_verbose)
 149         msg_info("deliver_file (%ld,%ld): %s",
 150                  (long) usr_attr.uid, (long) usr_attr.gid, path);
 151     if (vstream_fseek(state.msg_attr.fp, state.msg_attr.offset, SEEK_SET) < 0)
 152         msg_fatal("seek queue file %s: %m", state.msg_attr.queue_id);
 153
 154     /*
 155      * As the specified user, open or create the file, lock it, and append
 156      * the message.
 157      */
 158     copy_flags = MAIL_COPY_MBOX;
 159     if ((local_deliver_hdr_mask & DELIVER_HDR_FILE) == 0)
 160         copy_flags &= ~MAIL_COPY_DELIVERED;
 161
 162     set_eugid(usr_attr.uid, usr_attr.gid);
 163     mp = mbox_open(path, O_APPEND | O_CREAT | O_WRONLY,
 164                    S_IRUSR | S_IWUSR, &st, -1, -1,
 165                    local_mbox_lock_mask | MBOX_DOT_LOCK_MAY_FAIL,
 166                    "5.2.0", why);
 167     if (mp != 0) {
 168         if (S_ISREG(st.st_mode) && st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) {
 169             vstream_fclose(mp->fp);
 170             dsb_simple(why, "5.7.1", "file is executable");
 171         } else {
 172             mail_copy_status = mail_copy(COPY_ATTR(state.msg_attr), mp->fp,
 173                                          S_ISREG(st.st_mode) ? copy_flags :
 174                                          (copy_flags & ~MAIL_COPY_TOFILE),
 175                                          "\n", why);
 176         }
 177         mbox_release(mp);
 178     }
 179     set_eugid(var_owner_uid, var_owner_gid);
 180
 181     /*
 182      * As the mail system, bounce, defer delivery, or report success.
 183      */
 184     if (mail_copy_status & MAIL_COPY_STAT_CORRUPT) {
 185         deliver_status = DEL_STAT_DEFER;
 186     } else if (mail_copy_status != 0) {
 187         vstring_sprintf_prepend(why->reason,
 188                                 "cannot append message to file %s: ", path);
 189         deliver_status =
 190             (STR(why->status)[0] == '4' ?
 191              defer_append : bounce_append)
 192             (BOUNCE_FLAGS(state.request),
 193              BOUNCE_ATTR(state.msg_attr));
 194     } else {
 195         dsb_simple(why, "2.0.0", "delivered to file: %s", path);
 196         deliver_status = sent(BOUNCE_FLAGS(state.request),
 197                               SENT_ATTR(state.msg_attr));
 198     }
 199     return (deliver_status);
 200 }