1 /*
2 ** MasqMail
3 ** Copyright (C) 1999-2001 Oliver Kurth
4 ** Copyright (C) 2010 markus schnalke <meillo@marmaro.de>
5 **
6 ** This program is free software; you can redistribute it and/or modify
7 ** it under the terms of the GNU General Public License as published by
8 ** the Free Software Foundation; either version 2 of the License, or
9 ** (at your option) any later version.
10 **
11 ** This program is distributed in the hope that it will be useful,
12 ** but WITHOUT ANY WARRANTY; without even the implied warranty of
13 ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 ** GNU General Public License for more details.
15 **
16 ** You should have received a copy of the GNU General Public License
17 ** along with this program; if not, write to the Free Software
18 ** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19 */
20
21 #include "masqmail.h"
22 #include "readsock.h"
23
24 /*
25 ** I always forget these rfc numbers:
26 ** RFC 821 (SMTP)
27 ** RFC 1869 (ESMTP)
28 ** RFC 1870 (ESMTP SIZE)
29 ** RFC 2197 (ESMTP PIPELINE)
30 ** RFC 2554 (ESMTP AUTH)
31 */
32
33
34 smtp_cmd smtp_cmds[] = {
35 {SMTP_HELO, "HELO",},
36 {SMTP_EHLO, "EHLO",},
37 {SMTP_MAIL_FROM, "MAIL FROM:",},
38 {SMTP_RCPT_TO, "RCPT TO:",},
39 {SMTP_DATA, "DATA",},
40 {SMTP_QUIT, "QUIT",},
41 {SMTP_RSET, "RSET",},
42 {SMTP_NOOP, "NOOP",},
43 {SMTP_HELP, "HELP"},
44 };
45
46 static smtp_cmd_id
get_id(const gchar * line)47 get_id(const gchar *line)
48 {
49 gint i;
50 for (i = 0; i < SMTP_NUM_IDS; i++) {
51 if (strncasecmp(smtp_cmds[i].cmd, line, strlen(smtp_cmds[i].cmd)) == 0) {
52 return (smtp_cmd_id) i;
53 }
54 }
55 return SMTP_ERROR;
56 }
57
58 static gboolean
get_size(gchar * line,unsigned long * msize)59 get_size(gchar *line, unsigned long *msize) {
60 gchar *s = NULL;
61
62 /* hope we need not to handle cases like SiZe= ...*/
63 s = strstr(line, "SIZE=");
64 if (!s) {
65 /* try it in lowercase too */
66 if (!(s = strstr(line, "size="))) {
67 return FALSE;
68 }
69 }
70 s += 5;
71 *msize = atol(s);
72 DEBUG(5) debugf("get_size(): line=%s, msize=%ld\n", line, *msize);
73
74 return TRUE;
75 }
76
77
78 /*
79 ** this is a quick hack: we expect the address to be syntactically correct
80 ** and containing the mailbox only, though we first check for size in
81 ** smtp_in().
82 ** Return false if address is too long.
83 */
84 static gboolean
get_address(gchar * line,gchar * addr)85 get_address(gchar *line, gchar *addr)
86 {
87 gchar *p = line;
88 gchar *q = addr;
89
90 /* skip MAIL FROM: and RCPT TO: */
91 while (*p && (*p != ':')) {
92 p++;
93 }
94 p++;
95
96 /* skip spaces: */
97 while (*p && isspace(*p)) {
98 p++;
99 }
100
101 /* get address: */
102 while (*p && !isspace(*p)) {
103 if (q >= addr + MAX_ADDRESS-1) {
104 *q = '\0';
105 return FALSE;
106 }
107 *(q++) = *(p++);
108 }
109 *q = '\0';
110
111 return TRUE;
112 }
113
114 static smtp_connection*
create_base(gchar * remote_host)115 create_base(gchar *remote_host)
116 {
117 smtp_connection *base = g_malloc(sizeof(smtp_connection));
118 if (!base) {
119 return NULL;
120 }
121
122 base->remote_host = g_strdup(remote_host);
123
124 base->prot = PROT_SMTP;
125 base->next_id = 0;
126 base->helo_seen = 0;
127 base->from_seen = 0;
128 base->rcpt_seen = 0;
129 base->msg = NULL;
130
131 return base;
132 }
133
134 static void
smtp_printf(FILE * out,gchar * fmt,...)135 smtp_printf(FILE *out, gchar *fmt, ...)
136 {
137 va_list args;
138 va_start(args, fmt);
139
140 DEBUG(4) {
141 gchar buf[256];
142 va_list args_copy;
143
144 va_copy(args_copy, args);
145 vsnprintf(buf, 255, fmt, args_copy);
146 va_end(args_copy);
147
148 debugf(">>>%s\n", buf);
149 }
150
151 vfprintf(out, fmt, args);
152 fflush(out);
153
154 va_end(args);
155 }
156
157 void
smtp_in(FILE * in,FILE * out,gchar * remote_host,gchar * ident)158 smtp_in(FILE *in, FILE *out, gchar *remote_host, gchar *ident)
159 {
160 gchar *buffer;
161 smtp_cmd_id cmd_id;
162 message *msg = NULL;
163 smtp_connection *psc;
164 int len;
165 unsigned long msize;
166
167 DEBUG(5) debugf("smtp_in entered, remote_host = %s\n", remote_host);
168
169 psc = create_base(remote_host);
170 psc->msg = msg;
171
172 buffer = (gchar *) g_malloc(BUF_LEN);
173 if (!buffer) {
174 /* this check is actually unneccessary as g_malloc()
175 aborts on failure */
176 return;
177 }
178
179 /* send greeting string, containing ESMTP: */
180 smtp_printf(out, "220 %s MasqMail %s ESMTP\r\n", conf.host_name, VERSION);
181
182 while ((len = read_sockline(in, buffer, BUF_LEN, 5 * 60, READSOCKL_CHUG)) >= 0) {
183 cmd_id = get_id(buffer);
184
185 if (conf.defer_all) {
186 /* I need this to debug delivery failures */
187 smtp_printf(out, "421 %s service temporarily unavailable.\r\n", conf.host_name);
188 destroy_message(msg);
189 msg = NULL;
190 return;
191 }
192
193 switch (cmd_id) {
194 case SMTP_HELO:
195 psc->prot = PROT_SMTP;
196 psc->helo_seen = TRUE;
197 smtp_printf(out, "250 %s pretty old mailer, huh?\r\n", conf.host_name);
198 break;
199
200 case SMTP_EHLO:
201 psc->prot = PROT_ESMTP;
202 psc->helo_seen = TRUE;
203 smtp_printf(out, "250-%s Nice to meet you with ESMTP\r\n", conf.host_name);
204 smtp_printf(out, "250-SIZE %d\r\n", conf.max_msg_size);
205 smtp_printf(out, "250-PIPELINING\r\n");
206 smtp_printf(out, "250 HELP\r\n");
207 break;
208
209 case SMTP_MAIL_FROM:
210 {
211 gchar buf[MAX_ADDRESS];
212 address *addr;
213
214 if (!psc->helo_seen) {
215 smtp_printf(out, "503 need HELO or EHLO\r\n");
216 break;
217 }
218 if (psc->from_seen) {
219 smtp_printf(out, "503 MAIL FROM: already given.\r\n");
220 break;
221 }
222 if (get_size(buffer, &msize)) {
223 DEBUG(5) debugf("smtp_in(): get_size: msize=%ld, conf.mms=%d\n",
224 msize, conf.max_msg_size);
225 if (conf.max_msg_size && (msize > conf.max_msg_size)) {
226 smtp_printf(out, "552 Message size exceeds fixed limit.\r\n");
227 break;
228 }
229 }
230 if (!get_address(buffer, buf)) {
231 smtp_printf(out, "553 Address too long.\r\n");
232 break;
233 }
234
235 msg = create_message();
236 msg->received_host = remote_host ? g_strdup(remote_host) : NULL;
237 msg->received_prot = psc->prot;
238 msg->ident = ident ? g_strdup(ident) : NULL;
239 /* get transfer id and increment for next one */
240 msg->transfer_id = (psc->next_id)++;
241
242 if (remote_host) {
243 addr = create_address(buf, TRUE);
244 } else {
245 addr = create_address_qualified(buf, TRUE, conf.host_name);
246 }
247 if (!addr) {
248 smtp_printf(out, "501 %s: syntax error.\r\n", buf);
249 } else if (!addr->domain) {
250 smtp_printf(out, "501 return path must be qualified.\r\n", buf);
251 } else {
252 psc->from_seen = TRUE;
253 msg->return_path = addr;
254 smtp_printf(out, "250 OK %s is a nice guy.\r\n", addr->address);
255 }
256 }
257 break;
258
259 case SMTP_RCPT_TO:
260 {
261 char buf[MAX_ADDRESS];
262 address *addr;
263
264 if (!psc->helo_seen) {
265 smtp_printf(out, "503 need HELO or EHLO.\r\n");
266 break;
267 }
268 if (!psc->from_seen) {
269 smtp_printf(out, "503 need MAIL FROM: before RCPT TO:\r\n");
270 break;
271 }
272 if (!get_address(buffer, buf)) {
273 smtp_printf(out, "553 Address too long.\r\n");
274 break;
275 }
276
277 if (remote_host) {
278 addr = create_address(buf, TRUE);
279 } else {
280 addr = create_address_qualified(buf, TRUE, conf.host_name);
281 }
282 if (!addr) {
283 smtp_printf(out, "501 %s: syntax error in address.\r\n", buf);
284 break;
285 }
286 if (addr->local_part[0] == '|') {
287 smtp_printf(out, "501 %s: no pipe allowed for SMTP connections\r\n", buf);
288 break;
289 }
290 if (!addr->domain) {
291 /* TODO: ``postmaster'' may be unqualified */
292 smtp_printf(out, "501 recipient address must be qualified.\r\n", buf);
293 break;
294 }
295 if (!(conf.do_relay || addr_is_local(msg->return_path) || addr_is_local(addr))) {
296 smtp_printf(out, "550 relaying to %s denied.\r\n", addr_string(addr));
297 break;
298 }
299 psc->rcpt_seen = TRUE;
300 msg->rcpt_list = g_list_append(msg->rcpt_list, addr);
301 smtp_printf(out, "250 OK %s is our friend.\r\n", addr->address);
302 }
303 break;
304
305 case SMTP_DATA:
306 if (!psc->helo_seen) {
307 smtp_printf(out, "503 need HELO or EHLO.\r\n");
308 break;
309 }
310 if (!psc->rcpt_seen) {
311 smtp_printf(out, "503 need RCPT TO: before DATA\r\n");
312 break;
313 }
314 accept_error err;
315
316 smtp_printf(out, "354 okay, and do not forget the dot\r\n");
317
318 err = accept_message(in, msg, conf.do_save_envelope_to ? ACC_SAVE_ENVELOPE_TO : 0);
319 if (err != AERR_OK) {
320 switch (err) {
321 case AERR_TIMEOUT:
322 case AERR_EOF:
323 return;
324 case AERR_SIZE:
325 smtp_printf(out, "552 Error: message too large.\r\n");
326 return;
327 default:
328 /* should never happen: */
329 smtp_printf(out, "451 Unknown error\r\n");
330 return;
331 }
332 }
333
334
335 if (!spool_write(msg, TRUE)) {
336 smtp_printf(out, "451 Could not write spool file\r\n");
337 return;
338 }
339 pid_t pid;
340 smtp_printf(out, "250 OK id=%s\r\n", msg->uid);
341
342 if (remote_host != NULL) {
343 logwrite(LOG_NOTICE, "%s <= <%s@%s> host=%s with %s\n", msg->uid,
344 msg->return_path->local_part, msg->return_path->domain,
345 remote_host, prot_names[psc->prot]);
346 } else {
347 logwrite(LOG_NOTICE, "%s <= <%s@%s> with %s\n", msg->uid,
348 msg->return_path->local_part, msg->return_path->domain,
349 prot_names[psc->prot]);
350 }
351
352 if (conf.do_queue) {
353 DEBUG(1) debugf("queuing forced by configuration or option.\n");
354 } else {
355 pid = fork();
356 if (pid < 0) {
357 logwrite(LOG_ALERT, "could not fork for delivery, id = %s\n", msg->uid);
358 } else if (pid == 0) {
359 /* FIXME: most likely inverted exit code */
360 _exit(deliver(msg));
361 }
362 }
363 psc->rcpt_seen = psc->from_seen = FALSE;
364 destroy_message(msg);
365 msg = NULL;
366 break;
367
368 case SMTP_QUIT:
369 smtp_printf(out, "221 goodbye\r\n");
370 destroy_message(msg);
371 msg = NULL;
372 return;
373
374 case SMTP_RSET:
375 psc->from_seen = psc->rcpt_seen = FALSE;
376 destroy_message(msg);
377 msg = NULL;
378 smtp_printf(out, "250 OK\r\n");
379 break;
380
381 case SMTP_NOOP:
382 smtp_printf(out, "250 OK\r\n");
383 break;
384
385 case SMTP_HELP:
386 {
387 int i;
388
389 smtp_printf(out, "214-supported commands:\r\n");
390 for (i = 0; i < SMTP_NUM_IDS - 1; i++) {
391 smtp_printf(out, "214-%s\r\n", smtp_cmds[i].cmd);
392 }
393 smtp_printf(out, "214 %s\r\n", smtp_cmds[i].cmd);
394 }
395 break;
396
397 default:
398 smtp_printf(out, "501 command not recognized\r\n");
399 DEBUG(1) debugf("command not recognized, was '%s'\n", buffer);
400 break;
401 }
402 }
403 switch (len) {
404 case -3:
405 logwrite(LOG_NOTICE, "connection timed out\n");
406 break;
407 case -2:
408 logwrite(LOG_NOTICE, "line overflow\n");
409 break;
410 case -1:
411 logwrite(LOG_NOTICE, "received EOF\n");
412 break;
413 default:
414 break;
415 }
416 }
417