1
2 /*
3 * Copyright (C) Igor Sysoev
4 * Copyright (C) Nginx, Inc.
5 */
6
7
8 #include <ngx_config.h>
9 #include <ngx_core.h>
10 #include <ngx_event.h>
11 #include <ngx_mail.h>
12 #include <ngx_mail_pop3_module.h>
13
14
15 static ngx_int_t ngx_mail_pop3_user(ngx_mail_session_t *s, ngx_connection_t *c);
16 static ngx_int_t ngx_mail_pop3_pass(ngx_mail_session_t *s, ngx_connection_t *c);
17 static ngx_int_t ngx_mail_pop3_capa(ngx_mail_session_t *s, ngx_connection_t *c,
18 ngx_int_t stls);
19 static ngx_int_t ngx_mail_pop3_stls(ngx_mail_session_t *s, ngx_connection_t *c);
20 static ngx_int_t ngx_mail_pop3_apop(ngx_mail_session_t *s, ngx_connection_t *c);
21 static ngx_int_t ngx_mail_pop3_auth(ngx_mail_session_t *s, ngx_connection_t *c);
22
23
24 static u_char pop3_greeting[] = "+OK POP3 ready" CRLF;
25 static u_char pop3_ok[] = "+OK" CRLF;
26 static u_char pop3_next[] = "+ " CRLF;
27 static u_char pop3_username[] = "+ VXNlcm5hbWU6" CRLF;
28 static u_char pop3_password[] = "+ UGFzc3dvcmQ6" CRLF;
29 static u_char pop3_invalid_command[] = "-ERR invalid command" CRLF;
30
31
32 void
ngx_mail_pop3_init_session(ngx_mail_session_t * s,ngx_connection_t * c)33 ngx_mail_pop3_init_session(ngx_mail_session_t *s, ngx_connection_t *c)
34 {
35 u_char *p;
36 ngx_mail_core_srv_conf_t *cscf;
37 ngx_mail_pop3_srv_conf_t *pscf;
38
39 pscf = ngx_mail_get_module_srv_conf(s, ngx_mail_pop3_module);
40 cscf = ngx_mail_get_module_srv_conf(s, ngx_mail_core_module);
41
42 if (pscf->auth_methods
43 & (NGX_MAIL_AUTH_APOP_ENABLED|NGX_MAIL_AUTH_CRAM_MD5_ENABLED))
44 {
45 if (ngx_mail_salt(s, c, cscf) != NGX_OK) {
46 ngx_mail_session_internal_server_error(s);
47 return;
48 }
49
50 s->out.data = ngx_pnalloc(c->pool, sizeof(pop3_greeting) + s->salt.len);
51 if (s->out.data == NULL) {
52 ngx_mail_session_internal_server_error(s);
53 return;
54 }
55
56 p = ngx_cpymem(s->out.data, pop3_greeting, sizeof(pop3_greeting) - 3);
57 *p++ = ' ';
58 p = ngx_cpymem(p, s->salt.data, s->salt.len);
59
60 s->out.len = p - s->out.data;
61
62 } else {
63 ngx_str_set(&s->out, pop3_greeting);
64 }
65
66 c->read->handler = ngx_mail_pop3_init_protocol;
67
68 ngx_add_timer(c->read, cscf->timeout);
69
70 if (ngx_handle_read_event(c->read, 0) != NGX_OK) {
71 ngx_mail_close_connection(c);
72 }
73
74 ngx_mail_send(c->write);
75 }
76
77
78 void
ngx_mail_pop3_init_protocol(ngx_event_t * rev)79 ngx_mail_pop3_init_protocol(ngx_event_t *rev)
80 {
81 ngx_connection_t *c;
82 ngx_mail_session_t *s;
83
84 c = rev->data;
85
86 c->log->action = "in auth state";
87
88 if (rev->timedout) {
89 ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, "client timed out");
90 c->timedout = 1;
91 ngx_mail_close_connection(c);
92 return;
93 }
94
95 s = c->data;
96
97 if (s->buffer == NULL) {
98 if (ngx_array_init(&s->args, c->pool, 2, sizeof(ngx_str_t))
99 == NGX_ERROR)
100 {
101 ngx_mail_session_internal_server_error(s);
102 return;
103 }
104
105 s->buffer = ngx_create_temp_buf(c->pool, 128);
106 if (s->buffer == NULL) {
107 ngx_mail_session_internal_server_error(s);
108 return;
109 }
110 }
111
112 s->mail_state = ngx_pop3_start;
113 c->read->handler = ngx_mail_pop3_auth_state;
114
115 ngx_mail_pop3_auth_state(rev);
116 }
117
118
119 void
ngx_mail_pop3_auth_state(ngx_event_t * rev)120 ngx_mail_pop3_auth_state(ngx_event_t *rev)
121 {
122 ngx_int_t rc;
123 ngx_connection_t *c;
124 ngx_mail_session_t *s;
125
126 c = rev->data;
127 s = c->data;
128
129 ngx_log_debug0(NGX_LOG_DEBUG_MAIL, c->log, 0, "pop3 auth state");
130
131 if (rev->timedout) {
132 ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, "client timed out");
133 c->timedout = 1;
134 ngx_mail_close_connection(c);
135 return;
136 }
137
138 if (s->out.len) {
139 ngx_log_debug0(NGX_LOG_DEBUG_MAIL, c->log, 0, "pop3 send handler busy");
140 s->blocked = 1;
141
142 if (ngx_handle_read_event(c->read, 0) != NGX_OK) {
143 ngx_mail_close_connection(c);
144 return;
145 }
146
147 return;
148 }
149
150 s->blocked = 0;
151
152 rc = ngx_mail_read_command(s, c);
153
154 if (rc == NGX_AGAIN) {
155 if (ngx_handle_read_event(c->read, 0) != NGX_OK) {
156 ngx_mail_session_internal_server_error(s);
157 return;
158 }
159
160 return;
161 }
162
163 if (rc == NGX_ERROR) {
164 return;
165 }
166
167 ngx_str_set(&s->out, pop3_ok);
168
169 if (rc == NGX_OK) {
170 switch (s->mail_state) {
171
172 case ngx_pop3_start:
173
174 switch (s->command) {
175
176 case NGX_POP3_USER:
177 rc = ngx_mail_pop3_user(s, c);
178 break;
179
180 case NGX_POP3_CAPA:
181 rc = ngx_mail_pop3_capa(s, c, 1);
182 break;
183
184 case NGX_POP3_APOP:
185 rc = ngx_mail_pop3_apop(s, c);
186 break;
187
188 case NGX_POP3_AUTH:
189 rc = ngx_mail_pop3_auth(s, c);
190 break;
191
192 case NGX_POP3_QUIT:
193 s->quit = 1;
194 break;
195
196 case NGX_POP3_NOOP:
197 break;
198
199 case NGX_POP3_STLS:
200 rc = ngx_mail_pop3_stls(s, c);
201 break;
202
203 default:
204 rc = NGX_MAIL_PARSE_INVALID_COMMAND;
205 break;
206 }
207
208 break;
209
210 case ngx_pop3_user:
211
212 switch (s->command) {
213
214 case NGX_POP3_PASS:
215 rc = ngx_mail_pop3_pass(s, c);
216 break;
217
218 case NGX_POP3_CAPA:
219 rc = ngx_mail_pop3_capa(s, c, 0);
220 break;
221
222 case NGX_POP3_QUIT:
223 s->quit = 1;
224 break;
225
226 case NGX_POP3_NOOP:
227 break;
228
229 default:
230 rc = NGX_MAIL_PARSE_INVALID_COMMAND;
231 break;
232 }
233
234 break;
235
236 /* suppress warnings */
237 case ngx_pop3_passwd:
238 break;
239
240 case ngx_pop3_auth_login_username:
241 rc = ngx_mail_auth_login_username(s, c, 0);
242
243 ngx_str_set(&s->out, pop3_password);
244 s->mail_state = ngx_pop3_auth_login_password;
245 break;
246
247 case ngx_pop3_auth_login_password:
248 rc = ngx_mail_auth_login_password(s, c);
249 break;
250
251 case ngx_pop3_auth_plain:
252 rc = ngx_mail_auth_plain(s, c, 0);
253 break;
254
255 case ngx_pop3_auth_cram_md5:
256 rc = ngx_mail_auth_cram_md5(s, c);
257 break;
258
259 case ngx_pop3_auth_external:
260 rc = ngx_mail_auth_external(s, c, 0);
261 break;
262 }
263 }
264
265 switch (rc) {
266
267 case NGX_DONE:
268 ngx_mail_auth(s, c);
269 return;
270
271 case NGX_ERROR:
272 ngx_mail_session_internal_server_error(s);
273 return;
274
275 case NGX_MAIL_PARSE_INVALID_COMMAND:
276 s->mail_state = ngx_pop3_start;
277 s->state = 0;
278
279 ngx_str_set(&s->out, pop3_invalid_command);
280
281 /* fall through */
282
283 case NGX_OK:
284
285 s->args.nelts = 0;
286 s->buffer->pos = s->buffer->start;
287 s->buffer->last = s->buffer->start;
288
289 if (s->state) {
290 s->arg_start = s->buffer->start;
291 }
292
293 if (ngx_handle_read_event(c->read, 0) != NGX_OK) {
294 ngx_mail_session_internal_server_error(s);
295 return;
296 }
297
298 ngx_mail_send(c->write);
299 }
300 }
301
302 static ngx_int_t
ngx_mail_pop3_user(ngx_mail_session_t * s,ngx_connection_t * c)303 ngx_mail_pop3_user(ngx_mail_session_t *s, ngx_connection_t *c)
304 {
305 ngx_str_t *arg;
306
307 #if (NGX_MAIL_SSL)
308 if (ngx_mail_starttls_only(s, c)) {
309 return NGX_MAIL_PARSE_INVALID_COMMAND;
310 }
311 #endif
312
313 if (s->args.nelts != 1) {
314 return NGX_MAIL_PARSE_INVALID_COMMAND;
315 }
316
317 arg = s->args.elts;
318 s->login.len = arg[0].len;
319 s->login.data = ngx_pnalloc(c->pool, s->login.len);
320 if (s->login.data == NULL) {
321 return NGX_ERROR;
322 }
323
324 ngx_memcpy(s->login.data, arg[0].data, s->login.len);
325
326 ngx_log_debug1(NGX_LOG_DEBUG_MAIL, c->log, 0,
327 "pop3 login: \"%V\"", &s->login);
328
329 s->mail_state = ngx_pop3_user;
330
331 return NGX_OK;
332 }
333
334
335 static ngx_int_t
ngx_mail_pop3_pass(ngx_mail_session_t * s,ngx_connection_t * c)336 ngx_mail_pop3_pass(ngx_mail_session_t *s, ngx_connection_t *c)
337 {
338 ngx_str_t *arg;
339
340 if (s->args.nelts != 1) {
341 return NGX_MAIL_PARSE_INVALID_COMMAND;
342 }
343
344 arg = s->args.elts;
345 s->passwd.len = arg[0].len;
346 s->passwd.data = ngx_pnalloc(c->pool, s->passwd.len);
347 if (s->passwd.data == NULL) {
348 return NGX_ERROR;
349 }
350
351 ngx_memcpy(s->passwd.data, arg[0].data, s->passwd.len);
352
353 #if (NGX_DEBUG_MAIL_PASSWD)
354 ngx_log_debug1(NGX_LOG_DEBUG_MAIL, c->log, 0,
355 "pop3 passwd: \"%V\"", &s->passwd);
356 #endif
357
358 return NGX_DONE;
359 }
360
361
362 static ngx_int_t
ngx_mail_pop3_capa(ngx_mail_session_t * s,ngx_connection_t * c,ngx_int_t stls)363 ngx_mail_pop3_capa(ngx_mail_session_t *s, ngx_connection_t *c, ngx_int_t stls)
364 {
365 ngx_mail_pop3_srv_conf_t *pscf;
366
367 pscf = ngx_mail_get_module_srv_conf(s, ngx_mail_pop3_module);
368
369 #if (NGX_MAIL_SSL)
370
371 if (stls && c->ssl == NULL) {
372 ngx_mail_ssl_conf_t *sslcf;
373
374 sslcf = ngx_mail_get_module_srv_conf(s, ngx_mail_ssl_module);
375
376 if (sslcf->starttls == NGX_MAIL_STARTTLS_ON) {
377 s->out = pscf->starttls_capability;
378 return NGX_OK;
379 }
380
381 if (sslcf->starttls == NGX_MAIL_STARTTLS_ONLY) {
382 s->out = pscf->starttls_only_capability;
383 return NGX_OK;
384 }
385 }
386
387 #endif
388
389 s->out = pscf->capability;
390 return NGX_OK;
391 }
392
393
394 static ngx_int_t
ngx_mail_pop3_stls(ngx_mail_session_t * s,ngx_connection_t * c)395 ngx_mail_pop3_stls(ngx_mail_session_t *s, ngx_connection_t *c)
396 {
397 #if (NGX_MAIL_SSL)
398 ngx_mail_ssl_conf_t *sslcf;
399
400 if (c->ssl == NULL) {
401 sslcf = ngx_mail_get_module_srv_conf(s, ngx_mail_ssl_module);
402 if (sslcf->starttls) {
403 c->read->handler = ngx_mail_starttls_handler;
404 return NGX_OK;
405 }
406 }
407
408 #endif
409
410 return NGX_MAIL_PARSE_INVALID_COMMAND;
411 }
412
413
414 static ngx_int_t
ngx_mail_pop3_apop(ngx_mail_session_t * s,ngx_connection_t * c)415 ngx_mail_pop3_apop(ngx_mail_session_t *s, ngx_connection_t *c)
416 {
417 ngx_str_t *arg;
418 ngx_mail_pop3_srv_conf_t *pscf;
419
420 #if (NGX_MAIL_SSL)
421 if (ngx_mail_starttls_only(s, c)) {
422 return NGX_MAIL_PARSE_INVALID_COMMAND;
423 }
424 #endif
425
426 if (s->args.nelts != 2) {
427 return NGX_MAIL_PARSE_INVALID_COMMAND;
428 }
429
430 pscf = ngx_mail_get_module_srv_conf(s, ngx_mail_pop3_module);
431
432 if (!(pscf->auth_methods & NGX_MAIL_AUTH_APOP_ENABLED)) {
433 return NGX_MAIL_PARSE_INVALID_COMMAND;
434 }
435
436 arg = s->args.elts;
437
438 s->login.len = arg[0].len;
439 s->login.data = ngx_pnalloc(c->pool, s->login.len);
440 if (s->login.data == NULL) {
441 return NGX_ERROR;
442 }
443
444 ngx_memcpy(s->login.data, arg[0].data, s->login.len);
445
446 s->passwd.len = arg[1].len;
447 s->passwd.data = ngx_pnalloc(c->pool, s->passwd.len);
448 if (s->passwd.data == NULL) {
449 return NGX_ERROR;
450 }
451
452 ngx_memcpy(s->passwd.data, arg[1].data, s->passwd.len);
453
454 ngx_log_debug2(NGX_LOG_DEBUG_MAIL, c->log, 0,
455 "pop3 apop: \"%V\" \"%V\"", &s->login, &s->passwd);
456
457 s->auth_method = NGX_MAIL_AUTH_APOP;
458
459 return NGX_DONE;
460 }
461
462
463 static ngx_int_t
ngx_mail_pop3_auth(ngx_mail_session_t * s,ngx_connection_t * c)464 ngx_mail_pop3_auth(ngx_mail_session_t *s, ngx_connection_t *c)
465 {
466 ngx_int_t rc;
467 ngx_mail_pop3_srv_conf_t *pscf;
468
469 #if (NGX_MAIL_SSL)
470 if (ngx_mail_starttls_only(s, c)) {
471 return NGX_MAIL_PARSE_INVALID_COMMAND;
472 }
473 #endif
474
475 pscf = ngx_mail_get_module_srv_conf(s, ngx_mail_pop3_module);
476
477 if (s->args.nelts == 0) {
478 s->out = pscf->auth_capability;
479 s->state = 0;
480
481 return NGX_OK;
482 }
483
484 rc = ngx_mail_auth_parse(s, c);
485
486 switch (rc) {
487
488 case NGX_MAIL_AUTH_LOGIN:
489
490 ngx_str_set(&s->out, pop3_username);
491 s->mail_state = ngx_pop3_auth_login_username;
492
493 return NGX_OK;
494
495 case NGX_MAIL_AUTH_LOGIN_USERNAME:
496
497 ngx_str_set(&s->out, pop3_password);
498 s->mail_state = ngx_pop3_auth_login_password;
499
500 return ngx_mail_auth_login_username(s, c, 1);
501
502 case NGX_MAIL_AUTH_PLAIN:
503
504 ngx_str_set(&s->out, pop3_next);
505 s->mail_state = ngx_pop3_auth_plain;
506
507 return NGX_OK;
508
509 case NGX_MAIL_AUTH_CRAM_MD5:
510
511 if (!(pscf->auth_methods & NGX_MAIL_AUTH_CRAM_MD5_ENABLED)) {
512 return NGX_MAIL_PARSE_INVALID_COMMAND;
513 }
514
515 if (ngx_mail_auth_cram_md5_salt(s, c, "+ ", 2) == NGX_OK) {
516 s->mail_state = ngx_pop3_auth_cram_md5;
517 return NGX_OK;
518 }
519
520 return NGX_ERROR;
521
522 case NGX_MAIL_AUTH_EXTERNAL:
523
524 if (!(pscf->auth_methods & NGX_MAIL_AUTH_EXTERNAL_ENABLED)) {
525 return NGX_MAIL_PARSE_INVALID_COMMAND;
526 }
527
528 ngx_str_set(&s->out, pop3_username);
529 s->mail_state = ngx_pop3_auth_external;
530
531 return NGX_OK;
532 }
533
534 return rc;
535 }
536