camel/providers/pop3/camel-pop3-store.c


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/* camel-pop3-store.c : class for a pop3 store */

/* 
 * Authors:
 *   Dan Winship <danw@ximian.com>
 *   Michael Zucchi <notzed@ximian.com>
 *
 * Copyright (C) 2000-2002 Ximian, Inc. (www.ximian.com)
 *
 * This program is free software; you can redistribute it and/or 
 * modify it under the terms of version 2 of the GNU General Public 
 * License as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>

#include "camel-operation.h"

#include "camel-pop3-store.h"
#include "camel-pop3-folder.h"
#include "camel-stream-buffer.h"
#include "camel-session.h"
#include "camel-exception.h"
#include "camel-url.h"
#include "e-util/md5-utils.h"
#include "camel-pop3-engine.h"
#include "camel-sasl.h"
#include "camel-data-cache.h"
#include "camel-tcp-stream.h"
#include "camel-tcp-stream-raw.h"
#ifdef HAVE_SSL
#include "camel-tcp-stream-ssl.h"
#endif

/* Specified in RFC 1939 */
#define POP3_PORT 110

static CamelStoreClass *parent_class = NULL;

static void finalize (CamelObject *object);

static gboolean pop3_connect (CamelService *service, CamelException *ex);
static gboolean pop3_disconnect (CamelService *service, gboolean clean, CamelException *ex);
static GList *query_auth_types (CamelService *service, CamelException *ex);

static CamelFolder *get_folder (CamelStore *store, const char *folder_name, 
                guint32 flags, CamelException *ex);

static void init_trash (CamelStore *store);
static CamelFolder *get_trash  (CamelStore *store, CamelException *ex);

static void
camel_pop3_store_class_init (CamelPOP3StoreClass *camel_pop3_store_class)
{
    CamelServiceClass *camel_service_class =
        CAMEL_SERVICE_CLASS (camel_pop3_store_class);
    CamelStoreClass *camel_store_class =
        CAMEL_STORE_CLASS (camel_pop3_store_class);

    parent_class = CAMEL_STORE_CLASS (camel_type_get_global_classfuncs (camel_store_get_type ()));
    
    /* virtual method overload */
    camel_service_class->query_auth_types = query_auth_types;
    camel_service_class->connect = pop3_connect;
    camel_service_class->disconnect = pop3_disconnect;

    camel_store_class->get_folder = get_folder;
    camel_store_class->init_trash = init_trash;
    camel_store_class->get_trash = get_trash;
}


static void
camel_pop3_store_init (gpointer object, gpointer klass)
{
    ;
}

CamelType
camel_pop3_store_get_type (void)
{
    static CamelType camel_pop3_store_type = CAMEL_INVALID_TYPE;

    if (!camel_pop3_store_type) {
        camel_pop3_store_type = camel_type_register (CAMEL_STORE_TYPE,
                                 "CamelPOP3Store",
                                 sizeof (CamelPOP3Store),
                                 sizeof (CamelPOP3StoreClass),
                                 (CamelObjectClassInitFunc) camel_pop3_store_class_init,
                                 NULL,
                                 (CamelObjectInitFunc) camel_pop3_store_init,
                                 finalize);
    }

    return camel_pop3_store_type;
}

static void
finalize (CamelObject *object)
{
    CamelPOP3Store *pop3_store = CAMEL_POP3_STORE (object);

    /* force disconnect so we dont have it run later, after we've cleaned up some stuff */
    /* SIGH */

    camel_service_disconnect((CamelService *)pop3_store, TRUE, NULL);

    if (pop3_store->engine)
        camel_object_unref((CamelObject *)pop3_store->engine);
    if (pop3_store->cache)
        camel_object_unref((CamelObject *)pop3_store->cache);
}

enum {
    USE_SSL_NEVER,
    USE_SSL_ALWAYS,
    USE_SSL_WHEN_POSSIBLE
};

static gboolean
connect_to_server (CamelService *service, int ssl_mode, int try_starttls, int *stls_support, CamelException *ex)
{
    CamelPOP3Store *store = CAMEL_POP3_STORE (service);
    CamelStream *tcp_stream;
    CamelPOP3Command *pc;
    struct hostent *h;
    int clean_quit;
    int ret, port;
    
    h = camel_service_gethost (service, ex);
    if (!h)
        return FALSE;
    
    port = service->url->port ? service->url->port : 110;
    
#ifdef HAVE_SSL
    if (camel_url_get_param (service->url, "use_ssl")) {
        if (try_starttls)
            tcp_stream = camel_tcp_stream_ssl_new_raw (service, service->url->host);
        else {
            port = service->url->port ? service->url->port : 995;
            tcp_stream = camel_tcp_stream_ssl_new (service, service->url->host);
        }
    } else {
        tcp_stream = camel_tcp_stream_raw_new ();
    }
#else
    tcp_stream = camel_tcp_stream_raw_new ();
#endif /* HAVE_SSL */
    
    ret = camel_tcp_stream_connect (CAMEL_TCP_STREAM (tcp_stream), h, port);
    camel_free_host (h);
    if (ret == -1) {
        if (errno == EINTR)
            camel_exception_set (ex, CAMEL_EXCEPTION_USER_CANCEL,
                         _("Connection cancelled"));
        else
            camel_exception_setv (ex, CAMEL_EXCEPTION_SERVICE_UNAVAILABLE,
                          _("Could not connect to %s (port %d): %s"),
                          service->url->host, port, g_strerror (errno));
        return FALSE;
    }
    
    /* parent class connect initialization */
    if (CAMEL_SERVICE_CLASS (parent_class)->connect (service, ex) == FALSE) {
        camel_object_unref (CAMEL_OBJECT (tcp_stream));
        return FALSE;
    }
    
    store->engine = camel_pop3_engine_new (tcp_stream);
    
#ifdef HAVE_SSL
    if (store->engine) {
        if (stls_support)
            *stls_support = store->engine->capa & CAMEL_POP3_CAP_STLS;
        
        if (ssl_mode == USE_SSL_WHEN_POSSIBLE) {
            if (store->engine->capa & CAMEL_POP3_CAP_STLS)
                goto starttls;
        } else if (ssl_mode == USE_SSL_ALWAYS) {
            if (try_starttls) {
                if (store->engine->capa & CAMEL_POP3_CAP_STLS) {
                /* attempt to toggle STARTTLS mode */
                    goto starttls;
                } else {
                /* server doesn't support STARTTLS, abort */
                    camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                                  _("Failed to connect to POP server %s in secure mode: %s"),
                                  service->url->host, _("SSL/TLS extension not supported."));
                    /* we have the possibility of quitting cleanly here */
                    clean_quit = TRUE;
                    goto stls_exception;
                }
            }
        }
    }
#endif /* HAVE_SSL */
    
    camel_object_unref (CAMEL_OBJECT (tcp_stream));
    
    return store->engine != NULL;
    
#ifdef HAVE_SSL
 starttls:
    /* as soon as we send a STLS command, all hope is lost of a clean QUIT if problems arise */
    clean_quit = FALSE;
    
    pc = camel_pop3_engine_command_new (store->engine, 0, NULL, NULL, "STLS\r\n");
    while (camel_pop3_engine_iterate (store->engine, NULL) > 0)
        ;
    
    ret = pc->state == CAMEL_POP3_COMMAND_OK;
    camel_pop3_engine_command_free (store->engine, pc);
    
    if (ret == FALSE) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      _("Failed to connect to POP server %s in secure mode: %s"),
                      service->url->host, store->engine->line);
        goto stls_exception;
    }
    
    /* Okay, now toggle SSL/TLS mode */
    ret = camel_tcp_stream_ssl_enable_ssl (CAMEL_TCP_STREAM_SSL (tcp_stream));
    
    camel_object_unref (CAMEL_OBJECT (tcp_stream));
    
    if (ret == -1) {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                      _("Failed to connect to POP server %s in secure mode: %s"),
                      service->url->host, _("SSL negotiations failed"));
        goto stls_exception;
    }
    
    /* rfc2595, section 4 states that after a successful STLS
           command, the client MUST discard prior CAPA responses */
    camel_pop3_engine_reget_capabilities (store->engine);
    
    return TRUE;
    
 stls_exception:
    if (clean_quit) {
        /* try to disconnect cleanly */
        pc = camel_pop3_engine_command_new (store->engine, 0, NULL, NULL, "QUIT\r\n");
        while (camel_pop3_engine_iterate (store->engine, NULL) > 0)
            ;
        camel_pop3_engine_command_free (store->engine, pc);
    }
    
    camel_object_unref (CAMEL_OBJECT (store->engine));
    camel_object_unref (CAMEL_OBJECT (tcp_stream));
    store->engine = NULL;
    
    return FALSE;
#endif /* HAVE_SSL */
}

static struct {
    char *value;
    int mode;
} ssl_options[] = {
    { "",              USE_SSL_ALWAYS        },
    { "always",        USE_SSL_ALWAYS        },
    { "when-possible", USE_SSL_WHEN_POSSIBLE },
    { "never",         USE_SSL_NEVER         },
    { NULL,            USE_SSL_NEVER         },
};

#define EXCEPTION_RETRY(ex) (camel_exception_get_id (ex) != CAMEL_EXCEPTION_USER_CANCEL && \
                 camel_exception_get_id (ex) != CAMEL_EXCEPTION_SERVICE_UNAVAILABLE)

static gboolean
connect_to_server_wrapper (CamelService *service, CamelException *ex)
{
#ifdef HAVE_SSL
    const char *use_ssl;
    int stls_supported;
    int i, ssl_mode;
    
    use_ssl = camel_url_get_param (service->url, "use_ssl");
    if (use_ssl) {
        for (i = 0; ssl_options[i].value; i++)
            if (!strcmp (ssl_options[i].value, use_ssl))
                break;
        ssl_mode = ssl_options[i].mode;
    } else
        ssl_mode = USE_SSL_NEVER;
    
    if (ssl_mode == USE_SSL_ALWAYS) {
        /* First try STARTTLS */
        if (!connect_to_server (service, ssl_mode, TRUE, &stls_supported, ex))
            if (!stls_supported && EXCEPTION_RETRY (ex)) {
                /* STARTTLS is unavailable - okay, now try old-style SSL */
                camel_exception_clear (ex);
                return connect_to_server (service, ssl_mode, FALSE, NULL, ex);
            } else {
                return FALSE;
            }
        }
        
        return TRUE;
    } else if (ssl_mode == USE_SSL_WHEN_POSSIBLE) {
        /* If the server supports STARTTLS, use it */
        return connect_to_server (service, ssl_mode, TRUE, NULL, ex);
    } else {
        /* User doesn't care about SSL */
        return connect_to_server (service, ssl_mode, FALSE, NULL, ex);
    }
#else
    return connect_to_server (service, USE_SSL_NEVER, FALSE, NULL, ex);
#endif
}

extern CamelServiceAuthType camel_pop3_password_authtype;
extern CamelServiceAuthType camel_pop3_apop_authtype;

static GList *
query_auth_types (CamelService *service, CamelException *ex)
{
    CamelPOP3Store *store = CAMEL_POP3_STORE (service);
    GList *types = NULL;

        types = CAMEL_SERVICE_CLASS (parent_class)->query_auth_types (service, ex);
    if (camel_exception_is_set (ex))
        return NULL;

    if (connect_to_server_wrapper (service, NULL)) {
        types = g_list_concat(types, g_list_copy(store->engine->auth));
        pop3_disconnect (service, TRUE, NULL);
    } else {
        camel_exception_setv (ex, CAMEL_EXCEPTION_SERVICE_UNAVAILABLE,
                      _("Could not connect to POP server on %s"),
                      service->url->host);
    }

    return types;
}

/**
 * camel_pop3_store_expunge:
 * @store: the store
 * @ex: a CamelException
 *
 * Expunge messages from the store. This will result in the connection
 * being closed, which may cause later commands to fail if they can't
 * reconnect.
 **/
void
camel_pop3_store_expunge (CamelPOP3Store *store, CamelException *ex)
{
    CamelPOP3Command *pc;

    pc = camel_pop3_engine_command_new(store->engine, 0, NULL, NULL, "QUIT\r\n");
    while (camel_pop3_engine_iterate(store->engine, NULL) > 0)
        ;
    camel_pop3_engine_command_free(store->engine, pc);

    camel_service_disconnect (CAMEL_SERVICE (store), FALSE, ex);
}

static int
try_sasl(CamelPOP3Store *store, const char *mech, CamelException *ex)
{
    CamelPOP3Stream *stream = store->engine->stream;
    unsigned char *line, *resp;
    CamelSasl *sasl;
    unsigned int len;
    int ret;

    sasl = camel_sasl_new("pop3", mech, (CamelService *)store);
    if (sasl == NULL) {
        camel_exception_set (ex, CAMEL_EXCEPTION_SERVICE_CANT_AUTHENTICATE,
                     _("Unable to connect to POP server.\n"
                       "No support for requested "
                       "authentication mechanism."));
        return -1;
    }

    if (camel_stream_printf((CamelStream *)stream, "AUTH %s\r\n", mech) == -1)
        goto ioerror;

    while (1) {
        if (camel_pop3_stream_line(stream, &line, &len) == -1)
            goto ioerror;
        if (strncmp(line, "+OK", 3) == 0)
            break;
        if (strncmp(line, "-ERR", 4) == 0) {
            camel_exception_setv(ex, CAMEL_EXCEPTION_SERVICE_CANT_AUTHENTICATE,
                         _("SASL `%s' Login failed: %s"), mech, line);
            goto done;
        }
        /* If we dont get continuation, or the sasl object's run out of work, or we dont get a challenge,
           its a protocol error, so fail, and try reset the server */
        if (strncmp(line, "+ ", 2) != 0
            || camel_sasl_authenticated(sasl)
            || (resp = camel_sasl_challenge_base64(sasl, line+2, ex)) == NULL) {
            camel_stream_printf((CamelStream *)stream, "*\r\n");
            camel_pop3_stream_line(stream, &line, &len);
            camel_exception_setv(ex, CAMEL_EXCEPTION_SERVICE_CANT_AUTHENTICATE,
                         _("SASL Protocol error"));
            goto done;
        }

        ret = camel_stream_printf((CamelStream *)stream, "%s\r\n", resp);
        g_free(resp);
        if (ret == -1)
            goto ioerror;

    }
    camel_object_unref((CamelObject *)sasl);
    return 0;

ioerror:
    camel_exception_setv(ex, CAMEL_EXCEPTION_SERVICE_CANT_AUTHENTICATE,
                 _("I/O Error: %s"), strerror(errno));
done:
    camel_object_unref((CamelObject *)sasl);
    return -1;
}