summaryrefslogtreecommitdiff
path: root/mailbox/mu_auth.c
blob: b3d74a0e5c01d1bb71d28aba147e268aec22724f (plain)
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
/* GNU Mailutils -- a suite of utilities for electronic mail
   Copyright (C) 2002 Free Software Foundation, Inc.

   GNU Mailutils is free software; you can redistribute it and/or modify
   it under the terms of the GNU Lesser General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   GNU Mailutils 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 Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public License
   along with GNU Mailutils; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */


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

#include <unistd.h>
#include <sys/types.h>
#include <pwd.h>
#ifdef HAVE_SHADOW_H
# include <shadow.h>
#endif
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif
#ifdef HAVE_SECURITY_PAM_APPL_H
# include <security/pam_appl.h>
#endif
#ifdef HAVE_CRYPT_H
# include <crypt.h>
#endif

#include <mailutils/list.h>
#include <mailutils/iterator.h>
#include <mailutils/mailbox.h>
#include <mailutils/argp.h>
#include <mailutils/mu_auth.h>
#include <mailutils/error.h>
#include <mailutils/nls.h>

/*#define DEBUG(c) do { printf c; printf("\n"); } while (0)*/
#define DEBUG(c)

static void mu_auth_begin_setup __P((void));
static void mu_auth_finish_setup __P((void));

/* memory allocation */
int 
mu_auth_data_alloc (struct mu_auth_data **ptr,
		    const char *name,
		    const char *passwd,
		    uid_t uid,
		    gid_t gid,
		    const char *gecos,
		    const char *dir,
		    const char *shell,
		    const char *mailbox,
		    int change_uid)
{
  size_t size = sizeof (**ptr) +
                strlen (name) + 1 +
                strlen (passwd) + 1 +
                strlen (gecos) + 1 +
                strlen (dir) + 1 +
                strlen (shell) + 1 +
                strlen (mailbox) + 1;
  char *p;
  
  *ptr = malloc (size);
  if (!*ptr)
    return 1;

  p = (char *)(*ptr + 1);
  
#define COPY(f) \
  (*ptr)->##f = p; \
  strcpy (p, ##f); \
  p += strlen (##f) + 1
  
  COPY (name);
  COPY (passwd);
  COPY (gecos);
  COPY (dir);
  COPY (shell);
  COPY (mailbox);
  (*ptr)->uid = uid;
  (*ptr)->gid = gid;
  (*ptr)->change_uid = change_uid;
  return 0;
}

void
mu_auth_data_free (struct mu_auth_data *ptr)
{
  free (ptr);
}

/* Generic functions */

struct auth_stack_entry {
  char *name;        /* for diagnostics purposes */
  mu_auth_fp fun;
  void *func_data;
};

void
mu_insert_stack_entry (list_t *pflist, struct auth_stack_entry *entry)
{
  if (!*pflist && list_create (pflist))
    return;
  list_append (*pflist, entry);
}

int
mu_auth_runlist (list_t flist, void *return_data, void *key, void *data)
{
  int rc = 1;
  iterator_t itr;

  if (iterator_create (&itr, flist) == 0)
    {
      struct auth_stack_entry *ep;
      
      for (iterator_first (itr); rc && !iterator_is_done (itr);
	   iterator_next (itr))
	{
	  iterator_current (itr, (void **)&ep);
	  DEBUG(("trying %s", ep->name));
	  rc = ep->fun (return_data, key, ep->func_data, data);
	  DEBUG(("Result: %d", rc));
	}

      iterator_destroy (&itr);
    }
  return rc;
}

int
mu_auth_nosupport (void *usused_return_data, void *unused_key,
		   void *unused_func_data, void *unused_call_data)
{
  errno = ENOSYS;
  return 1;
}

/* II. Authorization: retrieving information about user */

static list_t mu_auth_by_name_list, _tmp_auth_by_name_list;
static list_t mu_auth_by_uid_list, _tmp_auth_by_uid_list;

struct mu_auth_data *
mu_get_auth_by_name (const char *username)
{
  struct mu_auth_data *auth = NULL;

  DEBUG(("mu_get_auth_by_name"));
  if (!mu_auth_by_name_list)
    mu_auth_begin_setup ();
  mu_auth_runlist (mu_auth_by_name_list, &auth, username, NULL);
  return auth;
}

struct mu_auth_data *
mu_get_auth_by_uid (uid_t uid)
{
  struct mu_auth_data *auth = NULL;

  DEBUG(("mu_get_auth_by_uid"));
  if (!mu_auth_by_uid_list)
    mu_auth_begin_setup ();
  mu_auth_runlist (mu_auth_by_uid_list, &auth, &uid, NULL);
  return auth;
}

/* III. Authentication: determining the authenticity of a user */

static list_t mu_authenticate_list, _tmp_authenticate_list;

int
mu_authenticate (struct mu_auth_data *auth_data, char *pass)
{
  DEBUG(("mu_authenticate"));
  if (!mu_authenticate_list)
    mu_auth_begin_setup ();
  return mu_auth_runlist (mu_authenticate_list, NULL, auth_data, pass);
}

/* Modules & configuration */


#define ARG_AUTHORIZATION 1
#define ARG_AUTHENTICATION 2

static error_t mu_auth_argp_parser __P((int key, char *arg,
					struct argp_state *state));

/* Options used by programs that use extended authentication mechanisms. */
static struct argp_option mu_auth_argp_option[] = {
  { "authentication", ARG_AUTHENTICATION, N_("MODLIST"), 0,
    "Set list of modules to be used for authentication", 0 },
  { "authorization", ARG_AUTHORIZATION, N_("MODLIST"), 0,
    "Set list of modules to be used for authorization", 0 },
  { NULL,      0, NULL, 0, NULL, 0 }
};

struct argp mu_auth_argp = {
  mu_auth_argp_option,
  mu_auth_argp_parser,
};

struct argp_child mu_auth_argp_child = {
  &mu_auth_argp,
  0,
  "Authentication options",
  0
};

static error_t
mu_auth_argp_parser (int key, char *arg, struct argp_state *state)
{
  switch (key)
    {
    case ARGP_KEY_FINI:
      mu_auth_finish_setup ();
      break;

      /* authentication */
    case ARG_AUTHORIZATION:
      mu_authorization_add_module_list (arg);
      break;
      
    case ARG_AUTHENTICATION:
      mu_authentication_add_module_list (arg);
      break;
      
    default:
      return ARGP_ERR_UNKNOWN;
    }
  return 0;
}


struct _module_handler {
  struct auth_stack_entry authenticate;
  struct auth_stack_entry auth_by_name;
  struct auth_stack_entry auth_by_uid;
};

static list_t module_handler_list;

void
mu_auth_register_module (struct mu_auth_module *mod)
{
  struct _module_handler *entry;
  
  if (mod->argp)
    {
      int i;
      struct argp_child *cp;
      
      if (mu_auth_argp.children)
	{
	  struct argp_child *tmp;
	  for (i = 0; mu_auth_argp.children[i].argp; i++)
	    ;
	  tmp = realloc ((void*) mu_auth_argp.children,
			 (i+1) * sizeof(mu_auth_argp.children[0]));
	  mu_auth_argp.children = tmp;
	}
      else
	{
	  mu_auth_argp.children = calloc (2, sizeof(mu_auth_argp.children[0]));
	  i = 0;
	}
	  
      if (!mu_auth_argp.children)
	{
	  mu_error ("not enough memory");
	  exit (1);
	}
      cp = (struct argp_child *) &mu_auth_argp.children[i];
      cp->argp = mod->argp;
      cp->flags = 0;
      cp->header = NULL;
      cp->group = 0; /* FIXME */
      cp++;
      cp->argp = NULL;
    }

  if (!module_handler_list && list_create (&module_handler_list))
    abort ();

  entry = malloc (sizeof (*entry));
  if (!entry)
    {
      mu_error ("not enough memory");
      exit (1);
    }
  entry->authenticate.name = mod->name;
  entry->authenticate.fun  = mod->authenticate;
  entry->authenticate.func_data = mod->authenticate_data;
  entry->auth_by_name.name = mod->name;
  entry->auth_by_name.fun = mod->auth_by_name;
  entry->auth_by_name.func_data = mod->auth_by_name_data;
  entry->auth_by_uid.name = mod->name;
  entry->auth_by_uid.fun = mod->auth_by_uid;
  entry->auth_by_uid.func_data = mod->auth_by_uid_data;
    
  list_append (module_handler_list, entry);
  
}

static struct _module_handler *
_locate (const char *name)
{
  struct _module_handler *rp = NULL;
  iterator_t itr;

  if (iterator_create (&itr, module_handler_list) == 0)
    {
      struct _module_handler *p;
      
      for (iterator_first (itr); !rp && !iterator_is_done (itr);
	   iterator_next (itr))
	{
	  iterator_current (itr, (void **)&p);
	  if (strcmp (p->authenticate.name, name) == 0)
	    rp = p;
	}

      iterator_destroy (&itr);
    }
  return rp;
}

static void
_add_module_list (const char *modlist, int (*fun)(const char *name))
{
  char *sp, *name;
  
  for (name = strtok_r ((char *)modlist, ":", &sp); name;
       name = strtok_r (NULL, ":", &sp))
    {
      if (fun (name))
	{
	  if (errno == ENOENT)
	    mu_error ("no such module: %s", name);
	  else
	    mu_error ("failed to add module %s: %s", strerror (errno));
	  exit (1);
	}
    }
}

int
mu_authorization_add_module (const char *name)
{
  struct _module_handler *mod = _locate (name);
  
  if (!mod)
    {
      errno = ENOENT;
      return 1;
    }
  mu_insert_stack_entry (&_tmp_auth_by_name_list, &mod->auth_by_name);
  mu_insert_stack_entry (&_tmp_auth_by_uid_list, &mod->auth_by_uid);
  return 0;
}

void
mu_authorization_add_module_list (const char *modlist)
{
  _add_module_list (modlist, mu_authorization_add_module);
}

int
mu_authentication_add_module (const char *name)
{
  struct _module_handler *mod = _locate (name);

  if (!mod)
    {
      errno = ENOENT;
      return 1;
    }
  mu_insert_stack_entry (&_tmp_authenticate_list, &mod->authenticate);
  return 0;
}

void
mu_authentication_add_module_list (const char *modlist)
{
  _add_module_list (modlist, mu_authentication_add_module);
}

/* ************************************************************************ */

/* Setup functions. Note that:
   1) If libmuath is not linked in, then "generic" and "system" modules
      are used unconditionally. This provides compatibility with the
      standard getpw.* functions.
   2) --authentication and --authorization modify only temporary lists,
      which get flushed to the main ones when mu_auth_finish_setup() is
      run. Thus, the default "generic:system" remain in force until
      argp_parse() exits. */ 
   
void
mu_auth_begin_setup ()
{
  iterator_t itr;

  if (!module_handler_list)
    {
      mu_auth_register_module (&mu_auth_generic_module); 
      mu_auth_register_module (&mu_auth_system_module);
    }
  
  if (!mu_authenticate_list)
    {
      if (iterator_create (&itr, module_handler_list) == 0)
	{
	  struct _module_handler *mod;
	  
	  for (iterator_first (itr); !iterator_is_done (itr);
	       iterator_next (itr))
	    {
	      iterator_current (itr, (void **)&mod);
	      mu_insert_stack_entry (&mu_authenticate_list,
				     &mod->authenticate);
	    }
	  iterator_destroy (&itr);
	}
    }

  if (!mu_auth_by_name_list)
    {
      if (iterator_create (&itr, module_handler_list) == 0)
	{
	  struct _module_handler *mod;
	  
	  for (iterator_first (itr); !iterator_is_done (itr);
	       iterator_next (itr))
	    {
	      iterator_current (itr, (void **)&mod);
	      mu_insert_stack_entry (&mu_auth_by_name_list, &mod->auth_by_name);
	      mu_insert_stack_entry (&mu_auth_by_uid_list, &mod->auth_by_uid);
	    }
	  iterator_destroy (&itr);
	}
    }
}

void
mu_auth_finish_setup ()
{
  list_destroy (&mu_authenticate_list);
  list_destroy (&mu_auth_by_name_list);
  list_destroy (&mu_auth_by_uid_list);
  
  mu_authenticate_list = _tmp_authenticate_list;
  _tmp_authenticate_list = NULL;
  mu_auth_by_name_list = _tmp_auth_by_name_list;
  _tmp_auth_by_name_list = NULL;
  mu_auth_by_uid_list = _tmp_auth_by_uid_list;
  _tmp_auth_by_uid_list = NULL;
  
  mu_auth_begin_setup ();
}


Return to:

Send suggestions and report system problems to the System administrator.