postfix.c

   1 /******************************************************************************/
   2 /*          postlicyd: a postfix policy daemon with a lot of features         */
   3 /*          ~~~~~~~~~                                                         */
   4 /*  ________________________________________________________________________  */
   5 /*                                                                            */
   6 /*  Redistribution and use in source and binary forms, with or without        */
   7 /*  modification, are permitted provided that the following conditions        */
   8 /*  are met:                                                                  */
   9 /*                                                                            */
  10 /*  1. Redistributions of source code must retain the above copyright         */
  11 /*     notice, this list of conditions and the following disclaimer.          */
  12 /*  2. Redistributions in binary form must reproduce the above copyright      */
  13 /*     notice, this list of conditions and the following disclaimer in the    */
  14 /*     documentation and/or other materials provided with the distribution.   */
  15 /*  3. The names of its contributors may not be used to endorse or promote    */
  16 /*     products derived from this software without specific prior written     */
  17 /*     permission.                                                            */
  18 /*                                                                            */
  19 /*  THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND   */
  20 /*  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE     */
  21 /*  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR        */
  22 /*  PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS    */
  23 /*  BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR    */
  24 /*  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF      */
  25 /*  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS  */
  26 /*  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN   */
  27 /*  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)   */
  28 /*  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF    */
  29 /*  THE POSSIBILITY OF SUCH DAMAGE.                                           */
  30 /******************************************************************************/
  31
  32 /*
  33  * Copyright © 2006-2007 Pierre Habouzit
  34  */
  35
  36 #include "common.h"
  37 #include "postfix.h"
  38 #include "buffer.h"
  39 #include "tokens.h"
  40
  41 #if 0
  42
  43 #define ishspace(c)  ((c) == ' ' || (c) == '\t')
  44
  45 typedef struct jpriv_t {
  46     buffer_t ibuf;
  47     buffer_t obuf;
  48     query_t query;
  49 } jpriv_t;
  50
  51 static jpriv_t *postfix_jpriv_init(jpriv_t *jp)
  52 {
  53     buffer_init(&jp->ibuf);
  54     buffer_init(&jp->obuf);
  55     query_init(&jp->query);
  56     return jp;
  57 }
  58 static void postfix_jpriv_wipe(jpriv_t *jp)
  59 {
  60     query_wipe(&jp->query);
  61     buffer_wipe(&jp->ibuf);
  62     buffer_wipe(&jp->obuf);
  63 }
  64 DO_NEW(jpriv_t, postfix_jpriv);
  65 DO_DELETE(jpriv_t, postfix_jpriv);
  66
  67 static int postfix_parsejob(query_t *query)
  68 {
  69 #define PARSE_CHECK(expr, error, ...)                                        \
  70     do {                                                                     \
  71         if (!(expr)) {                                                       \
  72             syslog(LOG_ERR, error, ##__VA_ARGS__);                           \
  73             return -1;                                                       \
  74         }                                                                    \
  75     } while (0)
  76
  77     char *p = vskipspaces(query->data.data);
  78
  79     while (*p) {
  80         char *k, *v;
  81         int klen, vlen, vtk;
  82
  83         while (ishspace(*p))
  84             p++;
  85         p = strchr(k = p, '=');
  86         PARSE_CHECK(p, "could not find '=' in line");
  87         for (klen = p - k; klen && ishspace(k[klen]); klen--);
  88         p += 1; /* skip = */
  89
  90         while (ishspace(*p))
  91             p++;
  92         p = strstr(v = p, "\r\n");
  93         PARSE_CHECK(p, "could not find final \\r\\n in line");
  94         for (vlen = p - v; vlen && ishspace(v[vlen]); vlen--);
  95         p += 2; /* skip \r\n */
  96
  97         vtk = tokenize(v, vlen);
  98         switch (tokenize(k, klen)) {
  99 #define CASE(up, low)  case PTK_##up: query->low = v; v[vlen] = '\0'; break;
 100             CASE(HELO_NAME,           helo_name);
 101             CASE(QUEUE_ID,            queue_id);
 102             CASE(SENDER,              sender);
 103             CASE(RECIPIENT,           recipient);
 104             CASE(RECIPIENT_COUNT,     recipient_count);
 105             CASE(CLIENT_ADDRESS,      client_address);
 106             CASE(CLIENT_NAME,         client_name);
 107             CASE(RCLIENT_NAME,        rclient_name);
 108             CASE(INSTANCE,            instance);
 109             CASE(SASL_METHOD,         sasl_method);
 110             CASE(SASL_USERNAME,       sasl_username);
 111             CASE(SASL_SENDER,         sasl_sender);
 112             CASE(SIZE,                size);
 113             CASE(CCERT_SUBJECT,       ccert_subject);
 114             CASE(CCERT_ISSUER,        ccert_issuer);
 115             CASE(CCSERT_FINGERPRINT,  ccsert_fingerprint);
 116             CASE(ENCRYPTION_PROTOCOL, encryption_protocol);
 117             CASE(ENCRYPTION_CIPHER,   encryption_cipher);
 118             CASE(ENCRYPTION_KEYSIZE,  encryption_keysize);
 119             CASE(ETRN_DOMAIN,         etrn_domain);
 120 #undef CASE
 121
 122           case PTK_REQUEST:
 123             PARSE_CHECK(vtk == PTK_SMTPD_ACCESS_POLICY,
 124                         "unexpected `request' value: %.*s", vlen, v);
 125             break;
 126
 127           case PTK_PROTOCOL_NAME:
 128             PARSE_CHECK(vtk == PTK_SMTP || vtk == PTK_ESMTP,
 129                         "unexpected `protocol_name' value: %.*s", vlen, v);
 130             query->esmtp = vtk == PTK_ESMTP;
 131             break;
 132
 133           case PTK_PROTOCOL_STATE:
 134             switch (vtk) {
 135 #define CASE(name)  case PTK_##name: query->state = SMTP_##name; break;
 136                 CASE(CONNECT);
 137                 CASE(EHLO);
 138                 CASE(HELO);
 139                 CASE(MAIL);
 140                 CASE(RCPT);
 141                 CASE(DATA);
 142                 CASE(END_OF_MESSAGE);
 143                 CASE(VRFY);
 144                 CASE(ETRN);
 145               default:
 146                 PARSE_CHECK(false, "unexpected `protocol_state` value: %.*s",
 147                             vlen, v);
 148 #undef CASE
 149             }
 150             break;
 151
 152           default:
 153             return -1;
 154         }
 155     }
 156
 157     return query->state == SMTP_UNKNOWN ? -1 : 0;
 158
 159 #undef PARSE_CHECK
 160 }
 161
 162 static void postfix_process(job_t *job)
 163 {
 164     int nb;
 165     const char *p;
 166
 167     switch (job->mode) {
 168       case JOB_LISTEN:
 169         if ((job = job_accept(job, JOB_READ))) {
 170             job->jdata   = postfix_jpriv_new();
 171             job->process = &postfix_process;
 172             job->stop    = &postfix_stop;
 173         }
 174         return;
 175
 176       case JOB_WRITE:
 177         nb = write(job->fd, job->jdata->obuf.data, job->jdata->obuf.len);
 178         if (nb < 0) {
 179             if ((job->error = errno != EINTR && errno != EAGAIN)) {
 180                 syslog(LOG_ERR, "unexpected problem on the socket: %m");
 181             }
 182             return;
 183         }
 184
 185         buffer_consume(&job->jdata->obuf, nb);
 186         if (job->jdata->obuf.len)
 187             return;
 188
 189         /* fall through */
 190
 191       case JOB_READ:
 192         nb = buffer_read(&job->jdata->ibuf, job->fd, -1);
 193         if (nb < 0) {
 194             if ((job->error = errno != EINTR && errno != EAGAIN)) {
 195                 syslog(LOG_ERR, "unexpected problem on the socket: %m");
 196             }
 197             return;
 198         }
 199         if (nb == 0) {
 200             syslog(LOG_ERR, "unexpected eof");
 201             job->error = true;
 202             return;
 203         }
 204
 205         p = strstr(skipspaces(job->jdata->ibuf.data), "\r\n\r\n");
 206         if (!p) {
 207             if (job->jdata->ibuf.len > SHRT_MAX) {
 208                 syslog(LOG_ERR, "too much data without CRLFCRLF");
 209                 job->error = true;
 210             }
 211             return;
 212         }
 213         p += 4;
 214
 215         query_reset(&job->jdata->query);
 216         buffer_add(&job->jdata->query.data, job->jdata->ibuf.data,
 217                    p - 2 - job->jdata->ibuf.data);
 218         buffer_consume(&job->jdata->query.data, p - job->jdata->ibuf.data);
 219
 220         if (postfix_parsejob(&job->jdata->query) < 0) {
 221             job->error = true;
 222             return;
 223         }
 224
 225         /* TODO: run the scenario */
 226         return;
 227
 228       default:
 229         job->error = true;
 230         return;
 231     }
 232 }
 233 #endif