diff options
Diffstat (limited to 'nss/nss_files/files-netgrp.c')
| -rw-r--r-- | nss/nss_files/files-netgrp.c | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/nss/nss_files/files-netgrp.c b/nss/nss_files/files-netgrp.c new file mode 100644 index 0000000000..8af55f209f --- /dev/null +++ b/nss/nss_files/files-netgrp.c @@ -0,0 +1,262 @@ +/* Netgroup file parser in nss_files modules. +Copyright (C) 1996 Free Software Foundation, Inc. +This file is part of the GNU C Library. +Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996. + +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 <ctype.h> +#include <errno.h> +#include <libc-lock.h> +#include <netdb.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include "nsswitch.h" +#include "netgroup.h" + +#define DATAFILE "/etc/netgroup" + + +/* Locks the static variables in this file. */ +__libc_lock_define_initialized (static, lock) + +/* We share a single place where we store the data for the current + netgroup. This buffer is allocated by `setnetgrent' and freed on + the next call of this function or when calling `endnetgrent'. */ +static char *data; +static size_t data_size; +static char *cursor; +static int first; + + +#define EXPAND(needed) \ + do \ + { \ + size_t old_cursor = cursor - data; \ + \ + data_size += 512 > 2 * needed ? 512 : 2 * needed; \ + data = realloc (data, data_size); \ + \ + if (data == NULL) \ + { \ + status = NSS_STATUS_UNAVAIL; \ + goto the_end; \ + } \ + \ + cursor = data + old_cursor; \ + } \ + while (0) + + +enum nss_status +_nss_files_setnetgrent (const char *group) +{ + FILE *fp; + enum nss_status status; + + if (group[0] == '\0') + return NSS_STATUS_UNAVAIL; + + __libc_lock_lock (lock); + + /* Find the netgroups file and open it. */ + fp = fopen (DATAFILE, "r"); + if (fp == NULL) + status = errno == EAGAIN ? NSS_STATUS_TRYAGAIN : NSS_STATUS_UNAVAIL; + else + { + /* Read the file line by line and try to find the description + GROUP. We must take care for long lines. */ + char *line = NULL; + size_t line_len = 0; + const ssize_t group_len = strlen (group); + + status = NSS_STATUS_NOTFOUND; + cursor = data; + + while (!feof (fp)) + { + ssize_t curlen = getline (&line, &line_len, fp); + int found; + + if (curlen < 0) + { + status = NSS_STATUS_NOTFOUND; + break; + } + + found = (curlen > group_len && strncmp (line, group, group_len) == 0 + && isspace (line[group_len])); + + /* Read the whole line (including continuation) and store it + if FOUND in nonzero. Otherwise we don't need it. */ + if (found) + { + /* Store the data from the first line. */ + EXPAND (curlen - group_len); + memcpy (cursor, &line[group_len + 1], curlen - group_len); + cursor += (curlen - group_len) - 1; + } + + while (line[curlen - 1] == '\n' && line[curlen - 2] == '\\') + { + /* Yes, we have a continuation line. */ + if (found) + /* Remove these characters from the stored line. */ + cursor -= 2; + + /* Get netxt line. */ + curlen = getline (&line, &line_len, fp); + if (curlen <= 0) + break; + + if (found) + { + /* Make sure we have enough room. */ + EXPAND (1 + curlen + 1); + + /* Add separator in case next line starts immediately. */ + *cursor++ = ' '; + + /* Copy new line. */ + memcpy (cursor, line, curlen + 1); + cursor += curlen; + } + } + + if (found) + { + /* Now we have read the line. */ + status = NSS_STATUS_SUCCESS; + cursor = data; + first = 1; + break; + } + } + + the_end: + /* We don't need the file and the line buffer anymore. */ + free (line); + fclose (fp); + } + + __libc_lock_unlock (lock); + + return status; +} + + +int +_nss_files_endnetgrent (void) +{ + __libc_lock_lock (lock); + + /* Free allocated memory for data if some is present. */ + if (data != NULL) + { + free (data); + data = NULL; + data_size = 0; + cursor = NULL; + } + + __libc_lock_unlock (lock); + + return NSS_STATUS_SUCCESS; +} + + +enum nss_status +_nss_netgroup_parseline (char **cursor, struct __netgrent *result, + char *buffer, int buflen) +{ + enum nss_status status; + const char *host, *user, *domain; + char *cp = *cursor; + + /* First skip leading spaces. */ + while (isspace (*cp)) + ++cp; + + if (*cp != '(') + return first ? NSS_STATUS_NOTFOUND : NSS_STATUS_RETURN; + + /* Match host name. */ + host = ++cp; + while (*cp != ',') + if (*cp++ == '\0') + return first ? NSS_STATUS_NOTFOUND : NSS_STATUS_RETURN; + + /* Match user name. */ + user = ++cp; + while (*cp != ',') + if (*cp++ == '\0') + return first ? NSS_STATUS_NOTFOUND : NSS_STATUS_RETURN; + + /* Match domain name. */ + domain = ++cp; + while (*cp != ')') + if (*cp++ == '\0') + return first ? NSS_STATUS_NOTFOUND : NSS_STATUS_RETURN; + ++cp; + + + /* When we got here we have found an entry. Before we can copy it + to the private buffer we have to make sure it is big enough. */ + if (cp - host > buflen) + { + __set_errno (ERANGE); + status = NSS_STATUS_UNAVAIL; + } + else + { + memcpy (buffer, host, cp - host); + + buffer[(user - host) - 1] = '\0'; + result->host = *host == ',' ? NULL : buffer; + + buffer[(domain - host) - 1] = '\0'; + result->user = *user == ',' ? NULL : buffer + (user - host); + + buffer[(cp - host) - 1] = '\0'; + result->domain = *domain == ')' ? NULL : buffer + (domain - host); + + status = NSS_STATUS_SUCCESS; + + /* Rememember where we stopped reading. */ + *cursor = cp; + + first = 0; + } + + return status; +} + + +enum nss_status +_nss_files_getnetgrent_r (struct __netgrent *result, char *buffer, int buflen) +{ + enum nss_status status; + + __libc_lock_lock (lock); + + status = _nss_netgroup_parseline (&cursor, result, buffer, buflen); + + __libc_lock_unlock (lock); + + return status; +} |