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 return;
142 }
143
144 s->blocked = 0;
145
146 rc = ngx_mail_read_command(s, c);
147
148 if (rc == NGX_AGAIN || rc == NGX_ERROR) {
149 return;
150 }
151
152 ngx_str_set(&s->out, pop3_ok);
153
154 if (rc == NGX_OK) {
155 switch (s->mail_state) {
156
157 case ngx_pop3_start:
158
159 switch (s->command) {
160
161 case NGX_POP3_USER:
162 rc = ngx_mail_pop3_user(s, c);
163 break;
164
165 case NGX_POP3_CAPA:
166 rc = ngx_mail_pop3_capa(s, c, 1);
167 break;
168
169 case NGX_POP3_APOP:
170 rc = ngx_mail_pop3_apop(s, c);
171 break;
172
173 case NGX_POP3_AUTH:
174 rc = ngx_mail_pop3_auth(s, c);
175 break;
176
177 case NGX_POP3_QUIT:
178 s->quit = 1;
179 break;
180
181 case NGX_POP3_NOOP:
182 break;
183
184 case NGX_POP3_STLS:
185 rc = ngx_mail_pop3_stls(s, c);
186 break;
187
188 default:
189 rc = NGX_MAIL_PARSE_INVALID_COMMAND;
190 break;
191 }
192
193 break;
194
195 case ngx_pop3_user:
196
197 switch (s->command) {
198
199 case NGX_POP3_PASS:
200 rc = ngx_mail_pop3_pass(s, c);
201 break;
202
203 case NGX_POP3_CAPA:
204 rc = ngx_mail_pop3_capa(s, c, 0);
205 break;
206
207 case NGX_POP3_QUIT:
208 s->quit = 1;
209 break;
210
211 case NGX_POP3_NOOP:
212 break;
213
214 default:
215 rc = NGX_MAIL_PARSE_INVALID_COMMAND;
216 break;
217 }
218
219 break;
220
221 /* suppress warnings */
222 case ngx_pop3_passwd:
223 break;
224
225 case ngx_pop3_auth_login_username:
226 rc = ngx_mail_auth_login_username(s, c, 0);
227
228 ngx_str_set(&s->out, pop3_password);
229 s->mail_state = ngx_pop3_auth_login_password;
230 break;
231
232 case ngx_pop3_auth_login_password:
233 rc = ngx_mail_auth_login_password(s, c);
234 break;
235
236 case ngx_pop3_auth_plain:
237 rc = ngx_mail_auth_plain(s, c, 0);
238 break;
239
240 case ngx_pop3_auth_cram_md5:
241 rc = ngx_mail_auth_cram_md5(s, c);
242 break;
243
244 case ngx_pop3_auth_external:
245 rc = ngx_mail_auth_external(s, c, 0);
246 break;
247 }
248 }
249
250 switch (rc) {
251
252 case NGX_DONE:
253 ngx_mail_auth(s, c);
254 return;
255
256 case NGX_ERROR:
257 ngx_mail_session_internal_server_error(s);
258 return;
259
260 case NGX_MAIL_PARSE_INVALID_COMMAND:
261 s->mail_state = ngx_pop3_start;
262 s->state = 0;
263
264 ngx_str_set(&s->out, pop3_invalid_command);
265
266 /* fall through */
267
268 case NGX_OK:
269
270 s->args.nelts = 0;
271 s->buffer->pos = s->buffer->start;
272 s->buffer->last = s->buffer->start;
273
274 if (s->state) {
275 s->arg_start = s->buffer->start;
276 }
277
278 ngx_mail_send(c->write);
279 }
280 }
281
282 static ngx_int_t
ngx_mail_pop3_user(ngx_mail_session_t * s,ngx_connection_t * c)283 ngx_mail_pop3_user(ngx_mail_session_t *s, ngx_connection_t *c)
284 {
285 ngx_str_t *arg;
286
287 #if (NGX_MAIL_SSL)
288 if (ngx_mail_starttls_only(s, c)) {
289 return NGX_MAIL_PARSE_INVALID_COMMAND;
290 }
291 #endif
292
293 if (s->args.nelts != 1) {
294 return NGX_MAIL_PARSE_INVALID_COMMAND;
295 }
296
297 arg = s->args.elts;
298 s->login.len = arg[0].len;
299 s->login.data = ngx_pnalloc(c->pool, s->login.len);
300 if (s->login.data == NULL) {
301 return NGX_ERROR;
302 }
303
304 ngx_memcpy(s->login.data, arg[0].data, s->login.len);
305
306 ngx_log_debug1(NGX_LOG_DEBUG_MAIL, c->log, 0,
307 "pop3 login: \"%V\"", &s->login);
308
309 s->mail_state = ngx_pop3_user;
310
311 return NGX_OK;
312 }
313
314
315 static ngx_int_t
ngx_mail_pop3_pass(ngx_mail_session_t * s,ngx_connection_t * c)316 ngx_mail_pop3_pass(ngx_mail_session_t *s, ngx_connection_t *c)
317 {
318 ngx_str_t *arg;
319
320 if (s->args.nelts != 1) {
321 return NGX_MAIL_PARSE_INVALID_COMMAND;
322 }
323
324 arg = s->args.elts;
325 s->passwd.len = arg[0].len;
326 s->passwd.data = ngx_pnalloc(c->pool, s->passwd.len);
327 if (s->passwd.data == NULL) {
328 return NGX_ERROR;
329 }
330
331 ngx_memcpy(s->passwd.data, arg[0].data, s->passwd.len);
332
333 #if (NGX_DEBUG_MAIL_PASSWD)
334 ngx_log_debug1(NGX_LOG_DEBUG_MAIL, c->log, 0,
335 "pop3 passwd: \"%V\"", &s->passwd);
336 #endif
337
338 return NGX_DONE;
339 }
340
341
342 static ngx_int_t
ngx_mail_pop3_capa(ngx_mail_session_t * s,ngx_connection_t * c,ngx_int_t stls)343 ngx_mail_pop3_capa(ngx_mail_session_t *s, ngx_connection_t *c, ngx_int_t stls)
344 {
345 ngx_mail_pop3_srv_conf_t *pscf;
346
347 pscf = ngx_mail_get_module_srv_conf(s, ngx_mail_pop3_module);
348
349 #if (NGX_MAIL_SSL)
350
351 if (stls && c->ssl == NULL) {
352 ngx_mail_ssl_conf_t *sslcf;
353
354 sslcf = ngx_mail_get_module_srv_conf(s, ngx_mail_ssl_module);
355
356 if (sslcf->starttls == NGX_MAIL_STARTTLS_ON) {
357 s->out = pscf->starttls_capability;
358 return NGX_OK;
359 }
360
361 if (sslcf->starttls == NGX_MAIL_STARTTLS_ONLY) {
362 s->out = pscf->starttls_only_capability;
363 return NGX_OK;
364 }
365 }
366
367 #endif
368
369 s->out = pscf->capability;
370 return NGX_OK;
371 }
372
373
374 static ngx_int_t
ngx_mail_pop3_stls(ngx_mail_session_t * s,ngx_connection_t * c)375 ngx_mail_pop3_stls(ngx_mail_session_t *s, ngx_connection_t *c)
376 {
377 #if (NGX_MAIL_SSL)
378 ngx_mail_ssl_conf_t *sslcf;
379
380 if (c->ssl == NULL) {
381 sslcf = ngx_mail_get_module_srv_conf(s, ngx_mail_ssl_module);
382 if (sslcf->starttls) {
383 c->read->handler = ngx_mail_starttls_handler;
384 return NGX_OK;
385 }
386 }
387
388 #endif
389
390 return NGX_MAIL_PARSE_INVALID_COMMAND;
391 }
392
393
394 static ngx_int_t
ngx_mail_pop3_apop(ngx_mail_session_t * s,ngx_connection_t * c)395 ngx_mail_pop3_apop(ngx_mail_session_t *s, ngx_connection_t *c)
396 {
397 ngx_str_t *arg;
398 ngx_mail_pop3_srv_conf_t *pscf;
399
400 #if (NGX_MAIL_SSL)
401 if (ngx_mail_starttls_only(s, c)) {
402 return NGX_MAIL_PARSE_INVALID_COMMAND;
403 }
404 #endif
405
406 if (s->args.nelts != 2) {
407 return NGX_MAIL_PARSE_INVALID_COMMAND;
408 }
409
410 pscf = ngx_mail_get_module_srv_conf(s, ngx_mail_pop3_module);
411
412 if (!(pscf->auth_methods & NGX_MAIL_AUTH_APOP_ENABLED)) {
413 return NGX_MAIL_PARSE_INVALID_COMMAND;
414 }
415
416 arg = s->args.elts;
417
418 s->login.len = arg[0].len;
419 s->login.data = ngx_pnalloc(c->pool, s->login.len);
420 if (s->login.data == NULL) {
421 return NGX_ERROR;
422 }
423
424 ngx_memcpy(s->login.data, arg[0].data, s->login.len);
425
426 s->passwd.len = arg[1].len;
427 s->passwd.data = ngx_pnalloc(c->pool, s->passwd.len);
428 if (s->passwd.data == NULL) {
429 return NGX_ERROR;
430 }
431
432 ngx_memcpy(s->passwd.data, arg[1].data, s->passwd.len);
433
434 ngx_log_debug2(NGX_LOG_DEBUG_MAIL, c->log, 0,
435 "pop3 apop: \"%V\" \"%V\"", &s->login, &s->passwd);
436
437 s->auth_method = NGX_MAIL_AUTH_APOP;
438
439 return NGX_DONE;
440 }
441
442
443 static ngx_int_t
ngx_mail_pop3_auth(ngx_mail_session_t * s,ngx_connection_t * c)444 ngx_mail_pop3_auth(ngx_mail_session_t *s, ngx_connection_t *c)
445 {
446 ngx_int_t rc;
447 ngx_mail_pop3_srv_conf_t *pscf;
448
449 #if (NGX_MAIL_SSL)
450 if (ngx_mail_starttls_only(s, c)) {
451 return NGX_MAIL_PARSE_INVALID_COMMAND;
452 }
453 #endif
454
455 pscf = ngx_mail_get_module_srv_conf(s, ngx_mail_pop3_module);
456
457 if (s->args.nelts == 0) {
458 s->out = pscf->auth_capability;
459 s->state = 0;
460
461 return NGX_OK;
462 }
463
464 rc = ngx_mail_auth_parse(s, c);
465
466 switch (rc) {
467
468 case NGX_MAIL_AUTH_LOGIN:
469
470 ngx_str_set(&s->out, pop3_username);
471 s->mail_state = ngx_pop3_auth_login_username;
472
473 return NGX_OK;
474
475 case NGX_MAIL_AUTH_LOGIN_USERNAME:
476
477 ngx_str_set(&s->out, pop3_password);
478 s->mail_state = ngx_pop3_auth_login_password;
479
480 return ngx_mail_auth_login_username(s, c, 1);
481
482 case NGX_MAIL_AUTH_PLAIN:
483
484 ngx_str_set(&s->out, pop3_next);
485 s->mail_state = ngx_pop3_auth_plain;
486
487 return NGX_OK;
488
489 case NGX_MAIL_AUTH_CRAM_MD5:
490
491 if (!(pscf->auth_methods & NGX_MAIL_AUTH_CRAM_MD5_ENABLED)) {
492 return NGX_MAIL_PARSE_INVALID_COMMAND;
493 }
494
495 if (ngx_mail_auth_cram_md5_salt(s, c, "+ ", 2) == NGX_OK) {
496 s->mail_state = ngx_pop3_auth_cram_md5;
497 return NGX_OK;
498 }
499
500 return NGX_ERROR;
501
502 case NGX_MAIL_AUTH_EXTERNAL:
503
504 if (!(pscf->auth_methods & NGX_MAIL_AUTH_EXTERNAL_ENABLED)) {
505 return NGX_MAIL_PARSE_INVALID_COMMAND;
506 }
507
508 ngx_str_set(&s->out, pop3_username);
509 s->mail_state = ngx_pop3_auth_external;
510
511 return NGX_OK;
512 }
513
514 return rc;
515 }
516