about summary refs log tree commit diff
path: root/nscd/nscd_initgroups.c
diff options
context:
space:
mode:
Diffstat (limited to 'nscd/nscd_initgroups.c')
-rw-r--r--nscd/nscd_initgroups.c158
1 files changed, 158 insertions, 0 deletions
diff --git a/nscd/nscd_initgroups.c b/nscd/nscd_initgroups.c
new file mode 100644
index 0000000000..513d35d1e1
--- /dev/null
+++ b/nscd/nscd_initgroups.c
@@ -0,0 +1,158 @@
+/* Copyright (C) 2004 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@redhat.com>, 2004.
+
+   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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <assert.h>
+#include <errno.h>
+#include <grp.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <not-cancel.h>
+
+#include "nscd-client.h"
+#include "nscd_proto.h"
+
+
+libc_locked_map_ptr (map_handle);
+/* Note that we only free the structure if necessary.  The memory
+   mapping is not removed since it is not visible to the malloc
+   handling.  */
+libc_freeres_fn (gr_map_free)
+{
+
+  if (map_handle.mapped != NO_MAPPING)
+    free (map_handle.mapped);
+}
+
+
+int
+__nscd_getgrouplist (const char *user, gid_t group, long int *size,
+		     gid_t **groupsp, long int limit)
+{
+  size_t userlen = strlen (user) + 1;
+  const initgr_response_header *initgr_resp = NULL;
+  char *respdata = NULL;
+  int retval = -1;
+  int sock = -1;
+  int gc_cycle;
+
+  /* If the mapping is available, try to search there instead of
+     communicating with the nscd.  */
+  struct mapped_database *mapped = __nscd_get_map_ref (GETFDGR, "group",
+						       &map_handle, &gc_cycle);
+ retry:
+  if (mapped != NO_MAPPING)
+    {
+      const struct datahead *found = __nscd_cache_search (INITGROUPS, user,
+							  userlen, mapped);
+      if (found != NULL)
+	{
+	  initgr_resp = &found->data[0].initgrdata;
+	  respdata = (char *) (initgr_resp + 1);
+	  char *recend = (char *) found->data + found->recsize;
+
+	  if (respdata + initgr_resp->ngrps * sizeof (int32_t) > recend)
+	    goto out;
+	}
+    }
+
+  /* If we do not have the cache mapped, try to get the data over the
+     socket.  */
+  initgr_response_header initgr_resp_mem;
+  if (initgr_resp == NULL)
+    {
+      sock = __nscd_open_socket (user, userlen, INITGROUPS, &initgr_resp_mem,
+				 sizeof (initgr_resp_mem));
+      if (sock == -1)
+	/* nscd not running or wrong version or hosts caching disabled.  */
+	__nss_not_use_nscd_group = 1;
+
+      initgr_resp = &initgr_resp_mem;
+    }
+
+  if (initgr_resp->found == 1)
+    {
+      /* The following code assumes that gid_t and int32_t are the
+	 same size.  This is the case for al existing implementation.
+	 If this should change some code needs to be added which
+	 doesn't use memcpy but instead copies each array element one
+	 by one.  */
+      assert (sizeof (int32_t) == sizeof (gid_t));
+
+      /* Make sure we have enough room.  We always count GROUP in even
+	 though we might not end up adding it.  */
+      if (*size < initgr_resp->ngrps + 1)
+	{
+	  gid_t *newp = realloc (*groupsp,
+				 (initgr_resp->ngrps + 1) * sizeof (gid_t));
+	  if (newp == NULL)
+	    /* We cannot increase the buffer size.  */
+	    goto out;
+
+	  *groupsp = newp;
+	  *size = initgr_resp->ngrps + 1;
+	}
+
+      if (respdata == NULL)
+	{
+	  /* Read the data from the socket.  */
+	  if ((size_t) TEMP_FAILURE_RETRY (__read (sock, *groupsp,
+						   initgr_resp->ngrps
+						   * sizeof (gid_t)))
+	      == initgr_resp->ngrps * sizeof (gid_t))
+	    retval = initgr_resp->ngrps;
+	}
+      else
+	{
+	  /* Just copy the data.  */
+	  retval = initgr_resp->ngrps;
+	  memcpy (*groupsp, respdata, retval * sizeof (gid_t));
+	}
+
+      /* Check whether GROUP is part of the mix.  If not, add it.  */
+      if (retval >= 0)
+	{
+	  int cnt;
+	  for (cnt = 0; cnt < retval; ++cnt)
+	    if ((*groupsp)[cnt] == group)
+	      break;
+
+	  if (cnt == retval)
+	    (*groupsp)[retval++] = group;
+	}
+    }
+  else
+    {
+      /* The `errno' to some value != ERANGE.  */
+      __set_errno (ENOENT);
+      /* Even though we have not found anything, the result is zero.  */
+      retval = 0;
+    }
+
+  if (sock != -1)
+    close_not_cancel_no_status (sock);
+ out:
+  if (__nscd_drop_map_ref (mapped, gc_cycle) != 0)
+    /* When we come here this means there has been a GC cycle while we
+       were looking for the data.  This means the data might have been
+       inconsistent.  Retry.  */
+    goto retry;
+
+  return retval;
+}