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-rw-r--r--nss/nss_compat/compat-grp.c682
1 files changed, 682 insertions, 0 deletions
diff --git a/nss/nss_compat/compat-grp.c b/nss/nss_compat/compat-grp.c
new file mode 100644
index 0000000000..4d51fc95ed
--- /dev/null
+++ b/nss/nss_compat/compat-grp.c
@@ -0,0 +1,682 @@
+/* Copyright (C) 1996-2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Thorsten Kukuk <kukuk@suse.de>, 1996.
+
+   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 <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <grp.h>
+#include <nss.h>
+#include <nsswitch.h>
+#include <stdio_ext.h>
+#include <string.h>
+#include <libc-lock.h>
+#include <kernel-features.h>
+
+static service_user *ni;
+static enum nss_status (*nss_setgrent) (int stayopen);
+static enum nss_status (*nss_getgrnam_r) (const char *name,
+					  struct group * grp, char *buffer,
+					  size_t buflen, int *errnop);
+static enum nss_status (*nss_getgrgid_r) (gid_t gid, struct group * grp,
+					  char *buffer, size_t buflen,
+					  int *errnop);
+static enum nss_status (*nss_getgrent_r) (struct group * grp, char *buffer,
+					  size_t buflen, int *errnop);
+static enum nss_status (*nss_endgrent) (void);
+
+/* Get the declaration of the parser function.  */
+#define ENTNAME grent
+#define STRUCTURE group
+#define EXTERN_PARSER
+#include <nss/nss_files/files-parse.c>
+
+/* Structure for remembering -group members ... */
+#define BLACKLIST_INITIAL_SIZE 512
+#define BLACKLIST_INCREMENT 256
+struct blacklist_t
+{
+  char *data;
+  int current;
+  int size;
+};
+
+struct ent_t
+{
+  bool files;
+  enum nss_status setent_status;
+  FILE *stream;
+  struct blacklist_t blacklist;
+};
+typedef struct ent_t ent_t;
+
+static ent_t ext_ent = { true, NSS_STATUS_SUCCESS, NULL, { NULL, 0, 0 }};
+
+/* Protect global state against multiple changers.  */
+__libc_lock_define_initialized (static, lock)
+
+/* Prototypes for local functions.  */
+static void blacklist_store_name (const char *, ent_t *);
+static bool in_blacklist (const char *, int, ent_t *);
+
+/* Initialize the NSS interface/functions. The calling function must
+   hold the lock.  */
+static void
+init_nss_interface (void)
+{
+  if (__nss_database_lookup ("group_compat", NULL, "nis", &ni) >= 0)
+    {
+      nss_setgrent = __nss_lookup_function (ni, "setgrent");
+      nss_getgrnam_r = __nss_lookup_function (ni, "getgrnam_r");
+      nss_getgrgid_r = __nss_lookup_function (ni, "getgrgid_r");
+      nss_getgrent_r = __nss_lookup_function (ni, "getgrent_r");
+      nss_endgrent = __nss_lookup_function (ni, "endgrent");
+    }
+}
+
+static enum nss_status
+internal_setgrent (ent_t *ent, int stayopen, int needent)
+{
+  enum nss_status status = NSS_STATUS_SUCCESS;
+
+  ent->files = true;
+
+  if (ent->blacklist.data != NULL)
+    {
+      ent->blacklist.current = 1;
+      ent->blacklist.data[0] = '|';
+      ent->blacklist.data[1] = '\0';
+    }
+  else
+    ent->blacklist.current = 0;
+
+  if (ent->stream == NULL)
+    {
+      ent->stream = fopen ("/etc/group", "rme");
+
+      if (ent->stream == NULL)
+	status = errno == EAGAIN ? NSS_STATUS_TRYAGAIN : NSS_STATUS_UNAVAIL;
+      else
+	/* We take care of locking ourself.  */
+	__fsetlocking (ent->stream, FSETLOCKING_BYCALLER);
+    }
+  else
+    rewind (ent->stream);
+
+  if (needent && status == NSS_STATUS_SUCCESS && nss_setgrent)
+    ent->setent_status = nss_setgrent (stayopen);
+
+  return status;
+}
+
+
+enum nss_status
+_nss_compat_setgrent (int stayopen)
+{
+  enum nss_status result;
+
+  __libc_lock_lock (lock);
+
+  if (ni == NULL)
+    init_nss_interface ();
+
+  result = internal_setgrent (&ext_ent, stayopen, 1);
+
+  __libc_lock_unlock (lock);
+
+  return result;
+}
+
+
+static enum nss_status
+internal_endgrent (ent_t *ent)
+{
+  if (ent->stream != NULL)
+    {
+      fclose (ent->stream);
+      ent->stream = NULL;
+    }
+
+  if (ent->blacklist.data != NULL)
+    {
+      ent->blacklist.current = 1;
+      ent->blacklist.data[0] = '|';
+      ent->blacklist.data[1] = '\0';
+    }
+  else
+    ent->blacklist.current = 0;
+
+  return NSS_STATUS_SUCCESS;
+}
+
+enum nss_status
+_nss_compat_endgrent (void)
+{
+  enum nss_status result;
+
+  __libc_lock_lock (lock);
+
+  if (nss_endgrent)
+    nss_endgrent ();
+
+  result = internal_endgrent (&ext_ent);
+
+  __libc_lock_unlock (lock);
+
+  return result;
+}
+
+/* get the next group from NSS  (+ entry) */
+static enum nss_status
+getgrent_next_nss (struct group *result, ent_t *ent, char *buffer,
+		   size_t buflen, int *errnop)
+{
+  if (!nss_getgrent_r)
+    return NSS_STATUS_UNAVAIL;
+
+  /* If the setgrent call failed, say so.  */
+  if (ent->setent_status != NSS_STATUS_SUCCESS)
+    return ent->setent_status;
+
+  do
+    {
+      enum nss_status status;
+
+      if ((status = nss_getgrent_r (result, buffer, buflen, errnop)) !=
+	  NSS_STATUS_SUCCESS)
+	return status;
+    }
+  while (in_blacklist (result->gr_name, strlen (result->gr_name), ent));
+
+  return NSS_STATUS_SUCCESS;
+}
+
+/* This function handle the +group entrys in /etc/group */
+static enum nss_status
+getgrnam_plusgroup (const char *name, struct group *result, ent_t *ent,
+		    char *buffer, size_t buflen, int *errnop)
+{
+  if (!nss_getgrnam_r)
+    return NSS_STATUS_UNAVAIL;
+
+  enum nss_status status = nss_getgrnam_r (name, result, buffer, buflen,
+					   errnop);
+  if (status != NSS_STATUS_SUCCESS)
+    return status;
+
+  if (in_blacklist (result->gr_name, strlen (result->gr_name), ent))
+    return NSS_STATUS_NOTFOUND;
+
+  /* We found the entry.  */
+  return NSS_STATUS_SUCCESS;
+}
+
+static enum nss_status
+getgrent_next_file (struct group *result, ent_t *ent,
+		    char *buffer, size_t buflen, int *errnop)
+{
+  struct parser_data *data = (void *) buffer;
+  while (1)
+    {
+      fpos_t pos;
+      int parse_res = 0;
+      char *p;
+
+      do
+	{
+	  /* We need at least 3 characters for one line.  */
+	  if (__glibc_unlikely (buflen < 3))
+	    {
+	    erange:
+	      *errnop = ERANGE;
+	      return NSS_STATUS_TRYAGAIN;
+	    }
+
+	  fgetpos (ent->stream, &pos);
+	  buffer[buflen - 1] = '\xff';
+	  p = fgets_unlocked (buffer, buflen, ent->stream);
+	  if (p == NULL && feof_unlocked (ent->stream))
+	    return NSS_STATUS_NOTFOUND;
+
+	  if (p == NULL || __builtin_expect (buffer[buflen - 1] != '\xff', 0))
+	    {
+	    erange_reset:
+	      fsetpos (ent->stream, &pos);
+	      goto erange;
+	    }
+
+	  /* Terminate the line for any case.  */
+	  buffer[buflen - 1] = '\0';
+
+	  /* Skip leading blanks.  */
+	  while (isspace (*p))
+	    ++p;
+	}
+      while (*p == '\0' || *p == '#' ||	/* Ignore empty and comment lines. */
+	     /* Parse the line.  If it is invalid, loop to
+	        get the next line of the file to parse.  */
+	     !(parse_res = _nss_files_parse_grent (p, result, data, buflen,
+						   errnop)));
+
+      if (__glibc_unlikely (parse_res == -1))
+	/* The parser ran out of space.  */
+	goto erange_reset;
+
+      if (result->gr_name[0] != '+' && result->gr_name[0] != '-')
+	/* This is a real entry.  */
+	break;
+
+      /* -group */
+      if (result->gr_name[0] == '-' && result->gr_name[1] != '\0'
+	  && result->gr_name[1] != '@')
+	{
+	  blacklist_store_name (&result->gr_name[1], ent);
+	  continue;
+	}
+
+      /* +group */
+      if (result->gr_name[0] == '+' && result->gr_name[1] != '\0'
+	  && result->gr_name[1] != '@')
+	{
+	  size_t len = strlen (result->gr_name);
+	  char buf[len];
+	  enum nss_status status;
+
+	  /* Store the group in the blacklist for the "+" at the end of
+	     /etc/group */
+	  memcpy (buf, &result->gr_name[1], len);
+	  status = getgrnam_plusgroup (&result->gr_name[1], result, ent,
+				       buffer, buflen, errnop);
+	  blacklist_store_name (buf, ent);
+	  if (status == NSS_STATUS_SUCCESS)	/* We found the entry. */
+	    break;
+	  else if (status == NSS_STATUS_RETURN /* We couldn't parse the entry*/
+		   || status == NSS_STATUS_NOTFOUND)	/* No group in NIS */
+	    continue;
+	  else
+	    {
+	      if (status == NSS_STATUS_TRYAGAIN)
+		/* The parser ran out of space.  */
+		goto erange_reset;
+
+	      return status;
+	    }
+	}
+
+      /* +:... */
+      if (result->gr_name[0] == '+' && result->gr_name[1] == '\0')
+	{
+	  ent->files = false;
+
+	  return getgrent_next_nss (result, ent, buffer, buflen, errnop);
+	}
+    }
+
+  return NSS_STATUS_SUCCESS;
+}
+
+
+enum nss_status
+_nss_compat_getgrent_r (struct group *grp, char *buffer, size_t buflen,
+			int *errnop)
+{
+  enum nss_status result = NSS_STATUS_SUCCESS;
+
+  __libc_lock_lock (lock);
+
+  /* Be prepared that the setgrent function was not called before.  */
+  if (ni == NULL)
+    init_nss_interface ();
+
+  if (ext_ent.stream == NULL)
+    result = internal_setgrent (&ext_ent, 1, 1);
+
+  if (result == NSS_STATUS_SUCCESS)
+    {
+      if (ext_ent.files)
+	result = getgrent_next_file (grp, &ext_ent, buffer, buflen, errnop);
+      else
+	result = getgrent_next_nss (grp, &ext_ent, buffer, buflen, errnop);
+    }
+  __libc_lock_unlock (lock);
+
+  return result;
+}
+
+/* Searches in /etc/group and the NIS/NIS+ map for a special group */
+static enum nss_status
+internal_getgrnam_r (const char *name, struct group *result, ent_t *ent,
+		     char *buffer, size_t buflen, int *errnop)
+{
+  struct parser_data *data = (void *) buffer;
+  while (1)
+    {
+      fpos_t pos;
+      int parse_res = 0;
+      char *p;
+
+      do
+	{
+	  /* We need at least 3 characters for one line.  */
+	  if (__glibc_unlikely (buflen < 3))
+	    {
+	    erange:
+	      *errnop = ERANGE;
+	      return NSS_STATUS_TRYAGAIN;
+	    }
+
+	  fgetpos (ent->stream, &pos);
+	  buffer[buflen - 1] = '\xff';
+	  p = fgets_unlocked (buffer, buflen, ent->stream);
+	  if (p == NULL && feof_unlocked (ent->stream))
+	    return NSS_STATUS_NOTFOUND;
+
+	  if (p == NULL || __builtin_expect (buffer[buflen - 1] != '\xff', 0))
+	    {
+	    erange_reset:
+	      fsetpos (ent->stream, &pos);
+	      goto erange;
+	    }
+
+	  /* Terminate the line for any case.  */
+	  buffer[buflen - 1] = '\0';
+
+	  /* Skip leading blanks.  */
+	  while (isspace (*p))
+	    ++p;
+	}
+      while (*p == '\0' || *p == '#' ||	/* Ignore empty and comment lines. */
+	     /* Parse the line.  If it is invalid, loop to
+	        get the next line of the file to parse.  */
+	     !(parse_res = _nss_files_parse_grent (p, result, data, buflen,
+						   errnop)));
+
+      if (__glibc_unlikely (parse_res == -1))
+	/* The parser ran out of space.  */
+	goto erange_reset;
+
+      /* This is a real entry.  */
+      if (result->gr_name[0] != '+' && result->gr_name[0] != '-')
+	{
+	  if (strcmp (result->gr_name, name) == 0)
+	    return NSS_STATUS_SUCCESS;
+	  else
+	    continue;
+	}
+
+      /* -group */
+      if (result->gr_name[0] == '-' && result->gr_name[1] != '\0')
+	{
+	  if (strcmp (&result->gr_name[1], name) == 0)
+	    return NSS_STATUS_NOTFOUND;
+	  else
+	    continue;
+	}
+
+      /* +group */
+      if (result->gr_name[0] == '+' && result->gr_name[1] != '\0')
+	{
+	  if (strcmp (name, &result->gr_name[1]) == 0)
+	    {
+	      enum nss_status status;
+
+	      status = getgrnam_plusgroup (name, result, ent,
+					   buffer, buflen, errnop);
+	      if (status == NSS_STATUS_RETURN)
+		/* We couldn't parse the entry */
+		continue;
+	      else
+		return status;
+	    }
+	}
+      /* +:... */
+      if (result->gr_name[0] == '+' && result->gr_name[1] == '\0')
+	{
+	  enum nss_status status;
+
+	  status = getgrnam_plusgroup (name, result, ent,
+				       buffer, buflen, errnop);
+	  if (status == NSS_STATUS_RETURN)
+	    /* We couldn't parse the entry */
+	    continue;
+	  else
+	    return status;
+	}
+    }
+
+  return NSS_STATUS_SUCCESS;
+}
+
+enum nss_status
+_nss_compat_getgrnam_r (const char *name, struct group *grp,
+			char *buffer, size_t buflen, int *errnop)
+{
+  ent_t ent = { true, NSS_STATUS_SUCCESS, NULL, { NULL, 0, 0 }};
+  enum nss_status result;
+
+  if (name[0] == '-' || name[0] == '+')
+    return NSS_STATUS_NOTFOUND;
+
+  __libc_lock_lock (lock);
+
+  if (ni == NULL)
+    init_nss_interface ();
+
+  __libc_lock_unlock (lock);
+
+  result = internal_setgrent (&ent, 0, 0);
+
+  if (result == NSS_STATUS_SUCCESS)
+    result = internal_getgrnam_r (name, grp, &ent, buffer, buflen, errnop);
+
+  internal_endgrent (&ent);
+
+  return result;
+}
+
+/* Searches in /etc/group and the NIS/NIS+ map for a special group id */
+static enum nss_status
+internal_getgrgid_r (gid_t gid, struct group *result, ent_t *ent,
+		     char *buffer, size_t buflen, int *errnop)
+{
+  struct parser_data *data = (void *) buffer;
+  while (1)
+    {
+      fpos_t pos;
+      int parse_res = 0;
+      char *p;
+
+      do
+	{
+	  /* We need at least 3 characters for one line.  */
+	  if (__glibc_unlikely (buflen < 3))
+	    {
+	    erange:
+	      *errnop = ERANGE;
+	      return NSS_STATUS_TRYAGAIN;
+	    }
+
+	  fgetpos (ent->stream, &pos);
+	  buffer[buflen - 1] = '\xff';
+	  p = fgets_unlocked (buffer, buflen, ent->stream);
+	  if (p == NULL && feof_unlocked (ent->stream))
+	    return NSS_STATUS_NOTFOUND;
+
+	  if (p == NULL || __builtin_expect (buffer[buflen - 1] != '\xff', 0))
+	    {
+	    erange_reset:
+	      fsetpos (ent->stream, &pos);
+	      goto erange;
+	    }
+
+	  /* Terminate the line for any case.  */
+	  buffer[buflen - 1] = '\0';
+
+	  /* Skip leading blanks.  */
+	  while (isspace (*p))
+	    ++p;
+	}
+      while (*p == '\0' || *p == '#' ||	/* Ignore empty and comment lines. */
+	     /* Parse the line.  If it is invalid, loop to
+	        get the next line of the file to parse.  */
+	     !(parse_res = _nss_files_parse_grent (p, result, data, buflen,
+						   errnop)));
+
+      if (__glibc_unlikely (parse_res == -1))
+	/* The parser ran out of space.  */
+	goto erange_reset;
+
+      /* This is a real entry.  */
+      if (result->gr_name[0] != '+' && result->gr_name[0] != '-')
+	{
+	  if (result->gr_gid == gid)
+	    return NSS_STATUS_SUCCESS;
+	  else
+	    continue;
+	}
+
+      /* -group */
+      if (result->gr_name[0] == '-' && result->gr_name[1] != '\0')
+	{
+	  blacklist_store_name (&result->gr_name[1], ent);
+	  continue;
+	}
+
+      /* +group */
+      if (result->gr_name[0] == '+' && result->gr_name[1] != '\0')
+	{
+	  /* Yes, no +1, see the memcpy call below.  */
+	  size_t len = strlen (result->gr_name);
+	  char buf[len];
+	  enum nss_status status;
+
+	  /* Store the group in the blacklist for the "+" at the end of
+	     /etc/group */
+	  memcpy (buf, &result->gr_name[1], len);
+	  status = getgrnam_plusgroup (&result->gr_name[1], result, ent,
+				       buffer, buflen, errnop);
+	  blacklist_store_name (buf, ent);
+	  if (status == NSS_STATUS_SUCCESS && result->gr_gid == gid)
+	    break;
+	  else
+	    continue;
+	}
+      /* +:... */
+      if (result->gr_name[0] == '+' && result->gr_name[1] == '\0')
+	{
+	  if (!nss_getgrgid_r)
+	    return NSS_STATUS_UNAVAIL;
+
+	  enum nss_status status = nss_getgrgid_r (gid, result, buffer, buflen,
+						   errnop);
+	  if (status == NSS_STATUS_RETURN) /* We couldn't parse the entry */
+	    return NSS_STATUS_NOTFOUND;
+	  else
+	    return status;
+	}
+    }
+
+  return NSS_STATUS_SUCCESS;
+}
+
+enum nss_status
+_nss_compat_getgrgid_r (gid_t gid, struct group *grp,
+			char *buffer, size_t buflen, int *errnop)
+{
+  ent_t ent = { true, NSS_STATUS_SUCCESS, NULL, { NULL, 0, 0 }};
+  enum nss_status result;
+
+  __libc_lock_lock (lock);
+
+  if (ni == NULL)
+    init_nss_interface ();
+
+  __libc_lock_unlock (lock);
+
+  result = internal_setgrent (&ent, 0, 0);
+
+  if (result == NSS_STATUS_SUCCESS)
+    result = internal_getgrgid_r (gid, grp, &ent, buffer, buflen, errnop);
+
+  internal_endgrent (&ent);
+
+  return result;
+}
+
+
+/* Support routines for remembering -@netgroup and -user entries.
+   The names are stored in a single string with `|' as separator. */
+static void
+blacklist_store_name (const char *name, ent_t *ent)
+{
+  int namelen = strlen (name);
+  char *tmp;
+
+  /* first call, setup cache */
+  if (ent->blacklist.size == 0)
+    {
+      ent->blacklist.size = MAX (BLACKLIST_INITIAL_SIZE, 2 * namelen);
+      ent->blacklist.data = malloc (ent->blacklist.size);
+      if (ent->blacklist.data == NULL)
+	return;
+      ent->blacklist.data[0] = '|';
+      ent->blacklist.data[1] = '\0';
+      ent->blacklist.current = 1;
+    }
+  else
+    {
+      if (in_blacklist (name, namelen, ent))
+	return;			/* no duplicates */
+
+      if (ent->blacklist.current + namelen + 1 >= ent->blacklist.size)
+	{
+	  ent->blacklist.size += MAX (BLACKLIST_INCREMENT, 2 * namelen);
+	  tmp = realloc (ent->blacklist.data, ent->blacklist.size);
+	  if (tmp == NULL)
+	    {
+	      free (ent->blacklist.data);
+	      ent->blacklist.size = 0;
+	      return;
+	    }
+	  ent->blacklist.data = tmp;
+	}
+    }
+
+  tmp = stpcpy (ent->blacklist.data + ent->blacklist.current, name);
+  *tmp++ = '|';
+  *tmp = '\0';
+  ent->blacklist.current += namelen + 1;
+
+  return;
+}
+
+/* Return whether ent->blacklist contains name.  */
+static bool
+in_blacklist (const char *name, int namelen, ent_t *ent)
+{
+  char buf[namelen + 3];
+  char *cp;
+
+  if (ent->blacklist.data == NULL)
+    return false;
+
+  buf[0] = '|';
+  cp = stpcpy (&buf[1], name);
+  *cp++ = '|';
+  *cp = '\0';
+  return strstr (ent->blacklist.data, buf) != NULL;
+}