postlicyd/main-postlicyd.c

   1 /******************************************************************************/
   2 /*          pfixtools: a collection of postfix related tools                  */
   3 /*          ~~~~~~~~~                                                         */
   4 /*  ________________________________________________________________________  */
   5 /*                                                                            */
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   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    */
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  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  * Copyright © 2008 Florent Bruneau
  35  */
  36
  37 #include <getopt.h>
  38
  39 #include "buffer.h"
  40 #include "common.h"
  41 #include "epoll.h"
  42 #include "policy_tokens.h"
  43 #include "server.h"
  44 #include "query.h"
  45 #include "config.h"
  46
  47 #define DAEMON_NAME             "postlicyd"
  48 #define DEFAULT_PORT            10000
  49 #define RUNAS_USER              "nobody"
  50 #define RUNAS_GROUP             "nogroup"
  51
  52 DECLARE_MAIN
  53
  54 static void *query_starter(server_t* server)
  55 {
  56     return query_new();
  57 }
  58
  59 static int postfix_parsejob(query_t *query, char *p)
  60 {
  61 #define PARSE_CHECK(expr, error, ...)                                        \
  62     do {                                                                     \
  63         if (!(expr)) {                                                       \
  64             syslog(LOG_ERR, error, ##__VA_ARGS__);                           \
  65             return -1;                                                       \
  66         }                                                                    \
  67     } while (0)
  68
  69     p_clear(query, 1);
  70     while (*p != '\n') {
  71         char *k, *v;
  72         int klen, vlen, vtk;
  73
  74         while (isblank(*p))
  75             p++;
  76         p = strchr(k = p, '=');
  77         PARSE_CHECK(p, "could not find '=' in line");
  78         for (klen = p - k; klen && isblank(k[klen]); klen--);
  79         p += 1; /* skip = */
  80
  81         while (isblank(*p))
  82             p++;
  83         p = strchr(v = p, '\n');
  84         PARSE_CHECK(p, "could not find final \\n in line");
  85         for (vlen = p - v; vlen && isblank(v[vlen]); vlen--);
  86         p += 1; /* skip \n */
  87
  88         vtk = policy_tokenize(v, vlen);
  89         switch (policy_tokenize(k, klen)) {
  90 #define CASE(up, low)  case PTK_##up: query->low = v; v[vlen] = '\0'; break;
  91             CASE(HELO_NAME,           helo_name);
  92             CASE(QUEUE_ID,            queue_id);
  93             CASE(SENDER,              sender);
  94             CASE(RECIPIENT,           recipient);
  95             CASE(RECIPIENT_COUNT,     recipient_count);
  96             CASE(CLIENT_ADDRESS,      client_address);
  97             CASE(CLIENT_NAME,         client_name);
  98             CASE(REVERSE_CLIENT_NAME, reverse_client_name);
  99             CASE(INSTANCE,            instance);
 100             CASE(SASL_METHOD,         sasl_method);
 101             CASE(SASL_USERNAME,       sasl_username);
 102             CASE(SASL_SENDER,         sasl_sender);
 103             CASE(SIZE,                size);
 104             CASE(CCERT_SUBJECT,       ccert_subject);
 105             CASE(CCERT_ISSUER,        ccert_issuer);
 106             CASE(CCERT_FINGERPRINT,   ccert_fingerprint);
 107             CASE(ENCRYPTION_PROTOCOL, encryption_protocol);
 108             CASE(ENCRYPTION_CIPHER,   encryption_cipher);
 109             CASE(ENCRYPTION_KEYSIZE,  encryption_keysize);
 110             CASE(ETRN_DOMAIN,         etrn_domain);
 111             CASE(STRESS,              stress);
 112 #undef CASE
 113
 114           case PTK_REQUEST:
 115             PARSE_CHECK(vtk == PTK_SMTPD_ACCESS_POLICY,
 116                         "unexpected `request' value: %.*s", vlen, v);
 117             break;
 118
 119           case PTK_PROTOCOL_NAME:
 120             PARSE_CHECK(vtk == PTK_SMTP || vtk == PTK_ESMTP,
 121                         "unexpected `protocol_name' value: %.*s", vlen, v);
 122             query->esmtp = vtk == PTK_ESMTP;
 123             break;
 124
 125           case PTK_PROTOCOL_STATE:
 126             switch (vtk) {
 127 #define CASE(name)  case PTK_##name: query->state = SMTP_##name; break;
 128                 CASE(CONNECT);
 129                 CASE(EHLO);
 130                 CASE(HELO);
 131                 CASE(MAIL);
 132                 CASE(RCPT);
 133                 CASE(DATA);
 134                 CASE(END_OF_MESSAGE);
 135                 CASE(VRFY);
 136                 CASE(ETRN);
 137               default:
 138                 PARSE_CHECK(false, "unexpected `protocol_state` value: %.*s",
 139                             vlen, v);
 140 #undef CASE
 141             }
 142             break;
 143
 144           default:
 145             syslog(LOG_WARNING, "unexpected key, skipped: %.*s", klen, k);
 146             continue;
 147         }
 148     }
 149
 150     return query->state == SMTP_UNKNOWN ? -1 : 0;
 151 #undef PARSE_CHECK
 152 }
 153
 154 __attribute__((format(printf,2,0)))
 155 static void policy_answer(server_t *pcy, const char *fmt, ...)
 156 {
 157     va_list args;
 158     const query_t* query = pcy->data;
 159
 160     buffer_addstr(&pcy->obuf, "action=");
 161     va_start(args, fmt);
 162     buffer_addvf(&pcy->obuf, fmt, args);
 163     va_end(args);
 164     buffer_addstr(&pcy->obuf, "\n\n");
 165     buffer_consume(&pcy->ibuf, query->eoq - pcy->ibuf.data);
 166     epoll_modify(pcy->fd, EPOLLIN | EPOLLOUT, pcy);
 167 }
 168
 169 static void policy_process(server_t *pcy, config_t *config)
 170 {
 171     const query_t* query = pcy->data;
 172     filter_t *filter = array_ptr(config->filters, config->entry_point);
 173     while (true) {
 174         filter_hook_t *hook = filter_run(filter, query);
 175         if (hook == NULL) {
 176             policy_answer(pcy, "DUNNO");
 177             return;
 178         } else if (hook->postfix) {
 179             policy_answer(pcy, "%s", hook->value);
 180             return;
 181         } else {
 182             filter = array_ptr(config->filters, hook->filter_id);
 183         }
 184     }
 185 }
 186
 187 static int policy_run(server_t *pcy, void* vconfig)
 188 {
 189     ssize_t search_offs = MAX(0, pcy->ibuf.len - 1);
 190     int nb = buffer_read(&pcy->ibuf, pcy->fd, -1);
 191     const char *eoq;
 192     query_t  *query  = pcy->data;
 193     config_t *config = vconfig;
 194
 195     if (nb < 0) {
 196         if (errno == EAGAIN || errno == EINTR)
 197             return 0;
 198         UNIXERR("read");
 199         return -1;
 200     }
 201     if (nb == 0) {
 202         if (pcy->ibuf.len)
 203             syslog(LOG_ERR, "unexpected end of data");
 204         return -1;
 205     }
 206
 207     if (!(eoq = strstr(pcy->ibuf.data + search_offs, "\n\n")))
 208         return 0;
 209
 210     if (postfix_parsejob(pcy->data, pcy->ibuf.data) < 0)
 211         return -1;
 212     query->eoq = eoq + strlen("\n\n");
 213     epoll_modify(pcy->fd, 0, pcy);
 214     policy_process(pcy, config);
 215     return 0;
 216 }
 217
 218 int start_listener(int port)
 219 {
 220     return start_server(port, NULL, NULL);
 221 }
 222
 223 /* administrivia {{{ */
 224
 225 void usage(void)
 226 {
 227     fputs("usage: "DAEMON_NAME" [options] config\n"
 228           "\n"
 229           "Options:\n"
 230           "    -l <port>    port to listen to\n"
 231           "    -p <pidfile> file to write our pid to\n"
 232           "    -f           stay in foreground\n"
 233          , stderr);
 234 }
 235
 236 /* }}} */
 237
 238 int main(int argc, char *argv[])
 239 {
 240     bool unsafe = false;
 241     const char *pidfile = NULL;
 242     bool daemonize = true;
 243     int port = DEFAULT_PORT;
 244
 245     for (int c = 0; (c = getopt(argc, argv, "hf" "l:p:")) >= 0; ) {
 246         switch (c) {
 247           case 'p':
 248             pidfile = optarg;
 249             break;
 250           case 'u':
 251             unsafe = true;
 252             break;
 253           case 'l':
 254             port = atoi(optarg);
 255             break;
 256           case 'f':
 257             daemonize = false;
 258             break;
 259           default:
 260             usage();
 261             return EXIT_FAILURE;
 262         }
 263     }
 264
 265     if (argc - optind != 1) {
 266         usage();
 267         return EXIT_FAILURE;
 268     }
 269
 270     config_t *config = config_read(argv[optind]);
 271     if (config == NULL) {
 272         return EXIT_FAILURE;
 273     }
 274
 275     if (common_setup(pidfile, false, RUNAS_USER, RUNAS_GROUP,
 276                      daemonize) != EXIT_SUCCESS
 277         || start_listener(port) < 0) {
 278         return EXIT_FAILURE;
 279     }
 280     {
 281         int res = server_loop(query_starter, (delete_client_t)query_delete,
 282                               policy_run, config);
 283         config_delete(&config);
 284         return res;
 285     }
 286 }