diff options
Diffstat (limited to 'REORG.TODO/nscd/nscd_getpw_r.c')
| -rw-r--r-- | REORG.TODO/nscd/nscd_getpw_r.c | 241 |
1 files changed, 241 insertions, 0 deletions
diff --git a/REORG.TODO/nscd/nscd_getpw_r.c b/REORG.TODO/nscd/nscd_getpw_r.c new file mode 100644 index 0000000000..b291d2fa44 --- /dev/null +++ b/REORG.TODO/nscd/nscd_getpw_r.c @@ -0,0 +1,241 @@ +/* Copyright (C) 1998-2017 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 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 <assert.h> +#include <errno.h> +#include <pwd.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <sys/mman.h> +#include <sys/socket.h> +#include <sys/uio.h> +#include <sys/un.h> +#include <not-cancel.h> +#include <_itoa.h> + +#include "nscd-client.h" +#include "nscd_proto.h" + +int __nss_not_use_nscd_passwd; + +static int nscd_getpw_r (const char *key, size_t keylen, request_type type, + struct passwd *resultbuf, char *buffer, + size_t buflen, struct passwd **result) + internal_function; + +int +__nscd_getpwnam_r (const char *name, struct passwd *resultbuf, char *buffer, + size_t buflen, struct passwd **result) +{ + if (name == NULL) + return -1; + + return nscd_getpw_r (name, strlen (name) + 1, GETPWBYNAME, resultbuf, + buffer, buflen, result); +} + +int +__nscd_getpwuid_r (uid_t uid, struct passwd *resultbuf, char *buffer, + size_t buflen, struct passwd **result) +{ + char buf[3 * sizeof (uid_t)]; + buf[sizeof (buf) - 1] = '\0'; + char *cp = _itoa_word (uid, buf + sizeof (buf) - 1, 10, 0); + + return nscd_getpw_r (cp, buf + sizeof (buf) - cp, GETPWBYUID, resultbuf, + buffer, buflen, result); +} + + +libc_locked_map_ptr (static, 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 (pw_map_free) +{ + if (map_handle.mapped != NO_MAPPING) + { + void *p = map_handle.mapped; + map_handle.mapped = NO_MAPPING; + free (p); + } +} + + +static int +internal_function +nscd_getpw_r (const char *key, size_t keylen, request_type type, + struct passwd *resultbuf, char *buffer, size_t buflen, + struct passwd **result) +{ + int gc_cycle; + int nretries = 0; + + /* If the mapping is available, try to search there instead of + communicating with the nscd. */ + struct mapped_database *mapped; + mapped = __nscd_get_map_ref (GETFDPW, "passwd", &map_handle, &gc_cycle); + + retry:; + const char *pw_name = NULL; + int retval = -1; + const char *recend = (const char *) ~UINTMAX_C (0); + pw_response_header pw_resp; + + if (mapped != NO_MAPPING) + { + struct datahead *found = __nscd_cache_search (type, key, keylen, mapped, + sizeof pw_resp); + if (found != NULL) + { + pw_name = (const char *) (&found->data[0].pwdata + 1); + pw_resp = found->data[0].pwdata; + recend = (const char *) found->data + found->recsize; + /* Now check if we can trust pw_resp fields. If GC is + in progress, it can contain anything. */ + if (mapped->head->gc_cycle != gc_cycle) + { + retval = -2; + goto out; + } + } + } + + int sock = -1; + if (pw_name == NULL) + { + sock = __nscd_open_socket (key, keylen, type, &pw_resp, + sizeof (pw_resp)); + if (sock == -1) + { + __nss_not_use_nscd_passwd = 1; + goto out; + } + } + + /* No value found so far. */ + *result = NULL; + + if (__glibc_unlikely (pw_resp.found == -1)) + { + /* The daemon does not cache this database. */ + __nss_not_use_nscd_passwd = 1; + goto out_close; + } + + if (pw_resp.found == 1) + { + /* Set the information we already have. */ + resultbuf->pw_uid = pw_resp.pw_uid; + resultbuf->pw_gid = pw_resp.pw_gid; + + char *p = buffer; + /* get pw_name */ + resultbuf->pw_name = p; + p += pw_resp.pw_name_len; + /* get pw_passwd */ + resultbuf->pw_passwd = p; + p += pw_resp.pw_passwd_len; + /* get pw_gecos */ + resultbuf->pw_gecos = p; + p += pw_resp.pw_gecos_len; + /* get pw_dir */ + resultbuf->pw_dir = p; + p += pw_resp.pw_dir_len; + /* get pw_pshell */ + resultbuf->pw_shell = p; + p += pw_resp.pw_shell_len; + + ssize_t total = p - buffer; + if (__glibc_unlikely (pw_name + total > recend)) + goto out_close; + if (__glibc_unlikely (buflen < total)) + { + __set_errno (ERANGE); + retval = ERANGE; + goto out_close; + } + + retval = 0; + if (pw_name == NULL) + { + ssize_t nbytes = __readall (sock, buffer, total); + + if (__glibc_unlikely (nbytes != total)) + { + /* The `errno' to some value != ERANGE. */ + __set_errno (ENOENT); + retval = ENOENT; + } + else + *result = resultbuf; + } + else + { + /* Copy the various strings. */ + memcpy (resultbuf->pw_name, pw_name, total); + + /* Try to detect corrupt databases. */ + if (resultbuf->pw_name[pw_resp.pw_name_len - 1] != '\0' + || resultbuf->pw_passwd[pw_resp.pw_passwd_len - 1] != '\0' + || resultbuf->pw_gecos[pw_resp.pw_gecos_len - 1] != '\0' + || resultbuf->pw_dir[pw_resp.pw_dir_len - 1] != '\0' + || resultbuf->pw_shell[pw_resp.pw_shell_len - 1] != '\0') + { + /* We cannot use the database. */ + retval = mapped->head->gc_cycle != gc_cycle ? -2 : -1; + goto out_close; + } + + *result = resultbuf; + } + } + else + { + /* Set errno to 0 to indicate no error, just no found record. */ + __set_errno (0); + /* Even though we have not found anything, the result is zero. */ + retval = 0; + } + + out_close: + 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 if possible. */ + if ((gc_cycle & 1) != 0 || ++nretries == 5 || retval == -1) + { + /* nscd is just running gc now. Disable using the mapping. */ + if (atomic_decrement_val (&mapped->counter) == 0) + __nscd_unmap (mapped); + mapped = NO_MAPPING; + } + + if (retval != -1) + goto retry; + } + + return retval; +} |