summaryrefslogtreecommitdiff
path: root/hurd/hurdauth.c
blob: 6c9324a5c92ac62362f2ccb2c57563702f125fe1 (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
/* Copyright (C) 1991-2019 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library 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 2.1 of the License, or (at your option) any later version.

   The GNU C Library 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 the GNU C Library; if not, see
   <https://www.gnu.org/licenses/>.  */

#include <hurd.h>
#include <hurd/msg_server.h>
#include <hurd/id.h>
#include <string.h>

int
_hurd_refport_secure_p (mach_port_t ref)
{
  if (ref == __mach_task_self ())
    return 1;
  if (__USEPORT (AUTH, ref == port))
    return 1;
  return 0;
}

kern_return_t
_S_msg_add_auth (mach_port_t me,
		 auth_t addauth)
{
  error_t err;
  auth_t newauth;
  uid_t *genuids, *gengids, *auxuids, *auxgids;
  mach_msg_type_number_t ngenuids, ngengids, nauxuids, nauxgids;
  uid_t *newgenuids, *newgengids, *newauxuids, *newauxgids;
  mach_msg_type_number_t nnewgenuids, nnewgengids, nnewauxuids, nnewauxgids;

  /* Create a list of ids and store it in NEWLISTP, length NEWLISTLEN.
     Keep all the ids in EXIST (len NEXIST), adding in those from NEW
     (len NNEW) which are not already there.  */
  error_t make_list (uid_t **newlistp, mach_msg_type_number_t *newlistlen,
		     uid_t *exist, mach_msg_type_number_t nexist,
		     uid_t *new, mach_msg_type_number_t nnew)
    {
      error_t urp;
      int i, j, k;
      vm_size_t offset;

      urp = __vm_allocate (mach_task_self (), (vm_address_t *) newlistp,
			   nexist + nnew * sizeof (uid_t), 1);
      if (urp)
	return urp;

      j = 0;
      for (i = 0; i < nexist; i++)
	(*newlistp)[j++] = exist[i];

      for (i = 0; i < nnew; i++)
	{
	  for (k = 0; k < nexist; k++)
	    if (exist[k] == new[i])
	      break;
	  if (k < nexist)
	    continue;

	  (*newlistp)[j++] = new[i];
	}

      offset = (round_page (nexist + nnew * sizeof (uid_t))
		- round_page (j * sizeof (uid_t)));
      if (offset)
	__vm_deallocate (mach_task_self (),
		         (vm_address_t) (*newlistp
				         + (nexist + nnew * sizeof (uid_t))),
		         offset);
      *newlistlen = j;
      return 0;
    }

  /* Find out what ids ADDAUTH refers to */

  genuids = gengids = auxuids = auxgids = 0;
  ngenuids = ngengids = nauxuids = nauxgids = 0;
  err = __auth_getids (addauth,
		       &genuids, &ngenuids,
		       &auxuids, &nauxuids,
		       &gengids, &ngengids,
		       &auxgids, &nauxgids);
  if (err)
    return err;

  /* OR in these ids to what we already have, creating a new list. */

  HURD_CRITICAL_BEGIN;
  __mutex_lock (&_hurd_id.lock);
  _hurd_check_ids ();

#define MAKE(genaux,uidgid) 						    \
  make_list (&new ## genaux ## uidgid ## s, 				    \
	     &nnew ## genaux ## uidgid ## s,				    \
	     _hurd_id.genaux.uidgid ## s,				    \
	     _hurd_id.genaux.n ## uidgid ## s,				    \
	     genaux ## uidgid ## s,					    \
	     n ## genaux ## uidgid ## s)

  err = MAKE (gen, uid);
  if (!err)
    MAKE (aux, uid);
  if (!err)
    MAKE (gen, gid);
  if (!err)
    MAKE (aux, gid);
#undef MAKE

  __mutex_unlock (&_hurd_id.lock);
  HURD_CRITICAL_END;


  /* Create the new auth port */

  if (!err)
    err = __USEPORT (AUTH,
		     __auth_makeauth (port,
				      &addauth, MACH_MSG_TYPE_MOVE_SEND, 1,
				      newgenuids, nnewgenuids,
				      newauxuids, nnewauxuids,
				      newgengids, nnewgengids,
				      newauxgids, nnewauxgids,
				      &newauth));

#define freeup(array, len) \
  if (array) \
    __vm_deallocate (mach_task_self (), (vm_address_t) array, \
		     len * sizeof (uid_t));

  freeup (genuids, ngenuids);
  freeup (auxuids, nauxuids);
  freeup (gengids, ngengids);
  freeup (auxgids, nauxgids);
  freeup (newgenuids, nnewgenuids);
  freeup (newauxuids, nnewauxuids);
  freeup (newgengids, nnewgengids);
  freeup (newauxgids, nnewauxgids);
#undef freeup

  if (err)
    return err;

  /* And install it. */

  err = __setauth (newauth);
  __mach_port_deallocate (__mach_task_self (), newauth);
  if (err)
    return errno;

  return 0;
}

kern_return_t
_S_msg_del_auth (mach_port_t me,
		 task_t task,
		 intarray_t uids, mach_msg_type_number_t nuids,
		 intarray_t gids, mach_msg_type_number_t ngids)
{
  error_t err;
  auth_t newauth;

  if (!_hurd_refport_secure_p (task))
    return EPERM;

  HURD_CRITICAL_BEGIN;
  __mutex_lock (&_hurd_id.lock);
  err = _hurd_check_ids ();

  if (!err)
    {
      size_t i, j;
      size_t nu = _hurd_id.gen.nuids, ng = _hurd_id.gen.ngids;
      uid_t newu[nu];
      gid_t newg[ng];

      memcpy (newu, _hurd_id.gen.uids, nu * sizeof (uid_t));
      memcpy (newg, _hurd_id.gen.gids, ng * sizeof (gid_t));

      for (j = 0; j < nuids; ++j)
	{
	  const uid_t uid = uids[j];
	  for (i = 0; i < nu; ++i)
	    if (newu[i] == uid)
	      /* Move the last uid into this slot, and decrease the
		 number of uids so the last slot is no longer used.  */
	      newu[i] = newu[--nu];
	}
      __vm_deallocate (__mach_task_self (),
		       (vm_address_t) uids, nuids * sizeof (uid_t));

      for (j = 0; j < ngids; ++j)
	{
	  const gid_t gid = gids[j];
	  for (i = 0; i < nu; ++i)
	    if (newu[i] == gid)
	      /* Move the last gid into this slot, and decrease the
		 number of gids so the last slot is no longer used.  */
	      newu[i] = newu[--nu];
	}
      __vm_deallocate (__mach_task_self (),
		       (vm_address_t) gids, ngids * sizeof (gid_t));

      err = __USEPORT (AUTH, __auth_makeauth
		       (port,
			NULL, MACH_MSG_TYPE_COPY_SEND, 0,
			newu, nu,
			_hurd_id.aux.uids, _hurd_id.aux.nuids,
			newg, ng,
			_hurd_id.aux.uids, _hurd_id.aux.ngids,
			&newauth));
    }
  __mutex_unlock (&_hurd_id.lock);
  HURD_CRITICAL_END;

  if (err)
    return err;

  err = __setauth (newauth);
  __mach_port_deallocate (__mach_task_self (), newauth);
  if (err)
    return errno;

  return 0;
}