summaryrefslogtreecommitdiff
path: root/nscd/nscd_getgr_r.c
blob: 85ebb0dc60959ae560c2615b2ddadec24847c024 (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
/* Copyright (C) 1998 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Thorsten Kukuk <kukuk@uni-paderborn.de>, 1998.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <errno.h>
#include <grp.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/uio.h>
#include <sys/un.h>

#include "nscd.h"
#include "nscd_proto.h"

int __nss_not_use_nscd_group;

static int __nscd_getgr_r (const char *key, request_type type,
			   struct group *resultbuf, char *buffer,
			   size_t buflen);

int
__nscd_getgrnam_r (const char *name, struct group *resultbuf, char *buffer,
		   size_t buflen)
{
  if (name == NULL)
    return 1;

  return __nscd_getgr_r (name, GETGRBYNAME, resultbuf, buffer, buflen);
}

int
__nscd_getgrgid_r (gid_t gid, struct group *resultbuf, char *buffer,
		   size_t buflen)
{
  char *p = buffer;
  int plen;

  plen = __snprintf (buffer, buflen, "%d", gid);
  if (plen == -1)
    {
      __set_errno (ERANGE);
      return -1;
    }
  p = buffer + plen + 1;

  return __nscd_getgr_r (buffer, GETGRBYGID, resultbuf, p, buflen - plen -1);
}

/* Create a socket connected to a name. */
static int
nscd_open_socket (void)
{
  struct sockaddr_un addr;
  int sock;
  int saved_errno = errno;

  sock = __socket (PF_UNIX, SOCK_STREAM, 0);
  if (sock < 0)
    {
      __set_errno (saved_errno);
      return -1;
    }

  addr.sun_family = AF_UNIX;
  strcpy (addr.sun_path, _PATH_NSCDSOCKET);
  if (__connect (sock, (struct sockaddr *) &addr, sizeof (addr)) < 0)
    {
      __close (sock);
      __set_errno (saved_errno);
      return -1;
    }

  return sock;
}

static int
__nscd_getgr_r (const char *key, request_type type, struct group *resultbuf,
		char *buffer, size_t buflen)
{
  int sock = nscd_open_socket ();
  request_header req;
  gr_response_header gr_resp;
  ssize_t nbytes;

  if (sock == -1)
    {
      __nss_not_use_nscd_group = 1;
      return 1;
    }

  req.version = NSCD_VERSION;
  req.type = type;
  req.key_len = strlen (key);
  nbytes = __write (sock, &req, sizeof (request_header));
  if (nbytes != sizeof (request_header))
    {
      __close (sock);
      return 1;
    }

  nbytes = __write (sock, key, req.key_len);
  if (nbytes != req.key_len)
    {
      __close (sock);
      return 1;
    }

  nbytes = __read (sock, &gr_resp, sizeof (gr_response_header));
  if (nbytes != sizeof (gr_response_header))
    {
      __close (sock);
      return 1;
    }

  if (gr_resp.found == -1)
    {
      /* The daemon does not cache this database.  */
      __close (sock);
      __nss_not_use_nscd_group = 1;
      return 1;
    }

  if (gr_resp.found == 1)
    {
      struct iovec *vec;
      size_t *len;
      char *p = buffer;
      int nblocks;
      size_t total_len;
      uintptr_t align;

      /* A first check whether the buffer is sufficently large is possible.  */
      if (buflen < gr_resp.gr_name_len + 1 + gr_resp.gr_passwd_len + 1)
	{
	  __set_errno (ERANGE);
	  __close (sock);
	  return -1;
	}

      /* Allocate the IOVEC.  */
      vec = alloca ((2 + gr_resp.gr_mem_len) * sizeof (struct iovec));
      len = alloca (gr_resp.gr_mem_len * sizeof (size_t));

      vec[0].iov_base = resultbuf->gr_name = p;
      vec[0].iov_len = gr_resp.gr_name_len;
      total_len = gr_resp.gr_name_len;
      p += gr_resp.gr_name_len + 1;

      vec[1].iov_base = resultbuf->gr_passwd = p;
      vec[1].iov_len = gr_resp.gr_passwd_len;
      total_len += gr_resp.gr_passwd_len;
      p += gr_resp.gr_passwd_len + 1;
      buflen -= total_len;
      nblocks = 2;

      if (gr_resp.gr_mem_len > 0)
	{
	  vec[2].iov_base = len;
	  vec[2].iov_len = gr_resp.gr_mem_len * sizeof (size_t);
	  total_len += gr_resp.gr_mem_len * sizeof (size_t);
	  nblocks = 3;
	}

      /* Get this data.  */
      if (__readv (sock, vec, nblocks) != total_len)
	{
	  __close (sock);
	  return 1;
	}

      /* Now we know the sizes.  First terminate the strings we just read. */
      resultbuf->gr_name[gr_resp.gr_name_len] = '\0';
      resultbuf->gr_passwd[gr_resp.gr_passwd_len] = '\0';

      resultbuf->gr_gid = gr_resp.gr_gid;

      /* Now allocate the buffer the array for the group members.  We must
	 align the pointer.  */
      align = ((__alignof__ (char *) - (p - ((char *) 0)))
	       & (__alignof__ (char *) - 1));
      if (align + (1 + gr_resp.gr_mem_len) * sizeof (char *) > buflen)
	{
	  __set_errno (ERANGE);
	  __close (sock);
	  return -1;
	}
      p += align;
      resultbuf->gr_mem = (char **) p;
      p += (1 + gr_resp.gr_mem_len) * sizeof (char *);
      buflen -= align + (1 + gr_resp.gr_mem_len) * sizeof (char *);

      resultbuf->gr_mem[gr_resp.gr_mem_len] = NULL;

      if (gr_resp.gr_mem_len > 0)
	{
	  /* Prepare reading the group members.  */
	  size_t i;

	  total_len = 0;
	  for (i = 0; i < gr_resp.gr_mem_len; ++i)
	    {
	      if (len[i] >= buflen)
		{
		  __set_errno (ERANGE);
		  __close (sock);
		  return -1;
		}

	      vec[i].iov_base = resultbuf->gr_mem[i] = p;
	      vec[i].iov_len = len[i];
	      total_len += len[i];
	      buflen -= len[i];
	      p += len[i];
	      *p++ = '\0';
	    }

	  while (i > UIO_MAXIOV)
	    {
	      if (__readv (sock, vec, UIO_MAXIOV) != total_len)
		{
		  __close (sock);
		  return -1;
		}
	      vec += UIO_MAXIOV;
	      i -= UIO_MAXIOV;
	    }

	  if (__readv (sock, vec, i) != total_len)
	    {
	      __close (sock);
	      return -1;
	    }
	}
      __close (sock);
      return 0;
    }
  else
    {
      __close (sock);
      return -1;
    }
}