src/src/spool_mbox.c

   1 /* $Cambridge: exim/src/src/spool_mbox.c,v 1.14 2008/01/16 09:56:55 tom Exp $ */
   2
   3 /*************************************************
   4 *     Exim - an Internet mail transport agent    *
   5 *************************************************/
   6
   7 /* Copyright (c) Tom Kistner <tom@duncanthrax.net> 2003-???? */
   8 /* License: GPL */
   9
  10 /* Code for setting up a MBOX style spool file inside a /scan/<msgid>
  11 sub directory of exim's spool directory. */
  12
  13 #include "exim.h"
  14 #ifdef WITH_CONTENT_SCAN
  15
  16 /* externals, we must reset them on unspooling */
  17 #ifdef WITH_OLD_DEMIME
  18 extern int demime_ok;
  19 extern struct file_extension *file_extensions;
  20 #endif
  21
  22 extern int malware_ok;
  23 extern int spam_ok;
  24
  25 int spool_mbox_ok = 0;
  26 uschar spooled_message_id[17];
  27
  28 /* returns a pointer to the FILE, and puts the size in bytes into mbox_file_size */
  29
  30 FILE *spool_mbox(unsigned long *mbox_file_size) {
  31   uschar message_subdir[2];
  32   uschar buffer[16384];
  33   uschar *temp_string;
  34   uschar *mbox_path;
  35   FILE *mbox_file = NULL;
  36   FILE *data_file = NULL;
  37   FILE *yield = NULL;
  38   header_line *my_headerlist;
  39   struct stat statbuf;
  40   int i, j;
  41   void *reset_point = store_get(0);
  42
  43   mbox_path = string_sprintf("%s/scan/%s/%s.eml", spool_directory, message_id,
  44     message_id);
  45
  46   /* Skip creation if already spooled out as mbox file */
  47   if (!spool_mbox_ok) {
  48     /* create temp directory inside scan dir, directory_make works recursively */
  49     temp_string = string_sprintf("scan/%s", message_id);
  50     if (!directory_make(spool_directory, temp_string, 0750, FALSE)) {
  51       log_write(0, LOG_MAIN|LOG_PANIC, "%s", string_open_failed(errno,
  52         "scan directory %s/scan/%s", spool_directory, temp_string));
  53       goto OUT;
  54     };
  55
  56     /* open [message_id].eml file for writing */
  57     mbox_file = modefopen(mbox_path, "wb", SPOOL_MODE);
  58     if (mbox_file == NULL) {
  59       log_write(0, LOG_MAIN|LOG_PANIC, "%s", string_open_failed(errno,
  60         "scan file %s", mbox_file));
  61       goto OUT;
  62     };
  63
  64     /* Generate mailbox headers. The $received_for variable is (up to at least
  65     Exim 4.64) never set here, because it is only set when expanding the
  66     contents of the Received: header line. However, the code below will use it
  67     if it should become available in future. */
  68
  69     temp_string = expand_string(
  70       US"From ${if def:return_path{$return_path}{MAILER-DAEMON}} ${tod_bsdinbox}\n"
  71       "${if def:sender_address{X-Envelope-From: <${sender_address}>\n}}"
  72       "${if def:recipients{X-Envelope-To: ${recipients}\n}}");
  73
  74     if (temp_string != NULL) {
  75       i = fwrite(temp_string, Ustrlen(temp_string), 1, mbox_file);
  76       if (i != 1) {
  77         log_write(0, LOG_MAIN|LOG_PANIC, "Error/short write while writing \
  78             mailbox headers to %s", mbox_path);
  79         goto OUT;
  80       };
  81     };
  82
  83     /* write all header lines to mbox file */
  84     my_headerlist = header_list;
  85     for (my_headerlist = header_list; my_headerlist != NULL;
  86       my_headerlist = my_headerlist->next)
  87     {
  88       /* skip deleted headers */
  89       if (my_headerlist->type == '*') continue;
  90
  91       i = fwrite(my_headerlist->text, my_headerlist->slen, 1, mbox_file);
  92       if (i != 1) {
  93         log_write(0, LOG_MAIN|LOG_PANIC, "Error/short write while writing \
  94             message headers to %s", mbox_path);
  95         goto OUT;
  96       };
  97     };
  98
  99     /* End headers */
 100     (void)fwrite("\n", 1, 1, mbox_file);
 101
 102     /* copy body file */
 103     message_subdir[1] = '\0';
 104     for (i = 0; i < 2; i++) {
 105       message_subdir[0] = (split_spool_directory == (i == 0))? message_id[5] : 0;
 106       temp_string = string_sprintf("%s/input/%s/%s-D", spool_directory,
 107         message_subdir, message_id);
 108       data_file = Ufopen(temp_string, "rb");
 109       if (data_file != NULL) break;
 110     };
 111
 112     if (data_file == NULL) {
 113       log_write(0, LOG_MAIN|LOG_PANIC, "Could not open datafile for message %s",
 114         message_id);
 115       goto OUT;
 116     };
 117
 118     /* The code used to use this line, but it doesn't work in Cygwin.
 119      *
 120      *  (void)fread(data_buffer, 1, 18, data_file);
 121      *
 122      * What's happening is that spool_mbox used to use an fread to jump over the
 123      * file header. That fails under Cygwin because the header is locked, but
 124      * doing an fseek succeeds. We have to output the leading newline
 125      * explicitly, because the one in the file is parted of the locked area.
 126      */
 127
 128     (void)fseek(data_file, SPOOL_DATA_START_OFFSET, SEEK_SET);
 129
 130     do {
 131       j = fread(buffer, 1, sizeof(buffer), data_file);
 132
 133       if (j > 0) {
 134         i = fwrite(buffer, j, 1, mbox_file);
 135         if (i != 1) {
 136           log_write(0, LOG_MAIN|LOG_PANIC, "Error/short write while writing \
 137               message body to %s", mbox_path);
 138           goto OUT;
 139         };
 140       };
 141     } while (j > 0);
 142
 143     (void)fclose(mbox_file);
 144     mbox_file = NULL;
 145
 146     Ustrcpy(spooled_message_id, message_id);
 147     spool_mbox_ok = 1;
 148   };
 149
 150   /* get the size of the mbox message and open [message_id].eml file for reading*/
 151   if (Ustat(mbox_path, &statbuf) != 0 ||
 152       (yield = Ufopen(mbox_path,"rb")) == NULL) {
 153     log_write(0, LOG_MAIN|LOG_PANIC, "%s", string_open_failed(errno,
 154       "scan file %s", mbox_file));
 155     goto OUT;
 156   };
 157
 158   *mbox_file_size = statbuf.st_size;
 159
 160   OUT:
 161   if (data_file) (void)fclose(data_file);
 162   if (mbox_file) (void)fclose(mbox_file);
 163   store_reset(reset_point);
 164   return yield;
 165 }
 166
 167 /* remove mbox spool file, demimed files and temp directory */
 168 void unspool_mbox(void) {
 169
 170   /* reset all exiscan state variables */
 171   #ifdef WITH_OLD_DEMIME
 172   demime_ok = 0;
 173   demime_errorlevel = 0;
 174   demime_reason = NULL;
 175   file_extensions = NULL;
 176   #endif
 177
 178   spam_ok = 0;
 179   malware_ok = 0;
 180
 181   if (spool_mbox_ok && !no_mbox_unspool) {
 182     uschar *mbox_path;
 183     uschar *file_path;
 184     int n;
 185     struct dirent *entry;
 186     DIR *tempdir;
 187
 188     mbox_path = string_sprintf("%s/scan/%s", spool_directory, spooled_message_id);
 189
 190     tempdir = opendir(CS mbox_path);
 191     /* loop thru dir & delete entries */
 192     while((entry = readdir(tempdir)) != NULL) {
 193       uschar *name = US entry->d_name;
 194       if (Ustrcmp(name, US".") == 0 || Ustrcmp(name, US"..") == 0) continue;
 195
 196       file_path = string_sprintf("%s/%s", mbox_path, name);
 197       debug_printf("unspool_mbox(): unlinking '%s'\n", file_path);
 198       n = unlink(CS file_path);
 199     };
 200
 201     closedir(tempdir);
 202
 203     /* remove directory */
 204     rmdir(CS mbox_path);
 205     store_reset(mbox_path);
 206   };
 207   spool_mbox_ok = 0;
 208 }
 209
 210 #endif