aboutsummaryrefslogtreecommitdiff
path: root/nis/nss_nisplus/nisplus-initgroups.c
blob: b54c53dba6510331e2727c15ff579d53a5d65af8 (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
/* Copyright (C) 1997-2013 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
   <http://www.gnu.org/licenses/>.  */

#include <atomic.h>
#include <nss.h>
#include <grp.h>
#include <ctype.h>
#include <errno.h>
#include <string.h>
#include <bits/libc-lock.h>
#include <rpcsvc/nis.h>

#include "nss-nisplus.h"
#include "nisplus-parser.h"
#include <libnsl.h>
#include <nis_intern.h>
#include <nis_xdr.h>

#define NISOBJVAL(col, obj) \
  ((obj)->EN_data.en_cols.en_cols_val[col].ec_value.ec_value_val)

#define NISOBJLEN(col, obj) \
  ((obj)->EN_data.en_cols.en_cols_val[col].ec_value.ec_value_len)

extern nis_name grp_tablename_val attribute_hidden;
extern size_t grp_tablename_len attribute_hidden;
extern enum nss_status _nss_grp_create_tablename (int *errnop);


enum nss_status
_nss_nisplus_initgroups_dyn (const char *user, gid_t group, long int *start,
			     long int *size, gid_t **groupsp, long int limit,
			     int *errnop)
{
  if (grp_tablename_val == NULL)
    {
      enum nss_status status = _nss_grp_create_tablename (errnop);

      if (status != NSS_STATUS_SUCCESS)
	return status;
    }

  nis_result *result;
  char buf[strlen (user) + 12 + grp_tablename_len];

  snprintf (buf, sizeof (buf), "[members=%s],%s", user, grp_tablename_val);

  result = nis_list (buf, FOLLOW_LINKS | FOLLOW_PATH | ALL_RESULTS, NULL, NULL);

  if (result == NULL)
    {
      *errnop = ENOMEM;
      return NSS_STATUS_TRYAGAIN;
    }

  if (__builtin_expect (niserr2nss (result->status) != NSS_STATUS_SUCCESS, 0))
    {
      enum nss_status status = niserr2nss (result->status);

      nis_freeresult (result);
      return status;
    }

  if (NIS_RES_NUMOBJ (result) == 0)
    {
    errout:
      nis_freeresult (result);
      return NSS_STATUS_NOTFOUND;
    }

  gid_t *groups = *groupsp;
  nis_object *obj = NIS_RES_OBJECT (result);
  for (unsigned int cnt = 0; cnt < NIS_RES_NUMOBJ (result); ++cnt, ++obj)
    {
      if (__type_of (obj) != NIS_ENTRY_OBJ
	  || strcmp (obj->EN_data.en_type, "group_tbl") != 0
	  || obj->EN_data.en_cols.en_cols_len < 4)
	continue;

      char *numstr = NISOBJVAL (2, obj);
      size_t len = NISOBJLEN (2, obj);
      if (len == 0 || numstr[0] == '\0')
	continue;

      gid_t gid;
      char *endp;
      if (__builtin_expect (numstr[len - 1] != '\0', 0))
	{
	  char numstrbuf[len + 1];
	  memcpy (numstrbuf, numstr, len);
	  numstrbuf[len] = '\0';
	  gid = strtoul (numstrbuf, &endp, 10);
	  if (*endp)
	    continue;
	}
      else
	{
	  gid = strtoul (numstr, &endp, 10);
	  if (*endp)
	    continue;
	}

      if (gid == group)
	continue;

      /* Insert this group.  */
      if (*start == *size)
	{
	  /* Need a bigger buffer.  */
	  long int newsize;

	  if (limit > 0 && *size == limit)
	    /* We reached the maximum.  */
	    break;

	  if (limit <= 0)
	    newsize = 2 * *size;
	  else
	    newsize = MIN (limit, 2 * *size);

	  gid_t *newgroups = realloc (groups, newsize * sizeof (*groups));
	  if (newgroups == NULL)
	    goto errout;
	  *groupsp = groups = newgroups;
	  *size = newsize;
	}

      groups[*start] = gid;
      *start += 1;
    }

  nis_freeresult (result);
  return NSS_STATUS_SUCCESS;
}