diff options
Diffstat (limited to 'nscd/pwdcache.c')
| -rw-r--r-- | nscd/pwdcache.c | 713 |
1 files changed, 174 insertions, 539 deletions
diff --git a/nscd/pwdcache.c b/nscd/pwdcache.c index 85b4fe9bde..5bf89a75ba 100644 --- a/nscd/pwdcache.c +++ b/nscd/pwdcache.c @@ -1,6 +1,7 @@ -/* Copyright (c) 1998 Free Software Foundation, Inc. +/* Cache handling for passwd lookup. + Copyright (C) 1998 Free Software Foundation, Inc. This file is part of the GNU C Library. - Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>, 1998. + Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998. 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 @@ -15,597 +16,231 @@ 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. */ + Boston, MA 02111-1307, USA. */ #include <errno.h> -#include <malloc.h> -#include <pthread.h> +#include <error.h> #include <pwd.h> +#include <stddef.h> +#include <stdio.h> +#include <stdlib.h> #include <string.h> +#include <time.h> #include <unistd.h> -#include <rpcsvc/nis.h> -#include <sys/types.h> -#include "dbg_log.h" #include "nscd.h" +#include "dbg_log.h" -static unsigned long int modulo = 211; -static unsigned long int postimeout = 600; -static unsigned long int negtimeout = 20; - -static unsigned long int poshit = 0; -static unsigned long int posmiss = 0; -static unsigned long int neghit = 0; -static unsigned long int negmiss = 0; - -struct pwdhash -{ - time_t create; - struct pwdhash *next; - struct passwd *pwd; -}; -typedef struct pwdhash pwdhash; - -struct uidhash -{ - struct uidhash *next; - struct passwd *pwptr; +/* This is the standard reply in case the service is disabled. */ +static const pw_response_header disabled = +{ + version: NSCD_VERSION, + found: -1, + pw_name_len: 0, + pw_passwd_len: 0, + pw_uid: -1, + pw_gid: -1, + pw_gecos_len: 0, + pw_dir_len: 0, + pw_shell_len: 0 }; -typedef struct uidhash uidhash; -struct neghash +/* This is the struct describing how to write this record. */ +const struct iovec pwd_iov_disabled = { - time_t create; - struct neghash *next; - char *key; + iov_base: (void *) &disabled, + iov_len: sizeof (disabled) }; -typedef struct neghash neghash; - -static pwdhash *pwdtbl; -static uidhash *uidtbl; -static neghash *negtbl; -static pthread_rwlock_t pwdlock = PTHREAD_RWLOCK_INITIALIZER; -static pthread_rwlock_t neglock = PTHREAD_RWLOCK_INITIALIZER; -static void *pwdtable_update (void *); -static void *negtable_update (void *); - -void -get_pw_stat (stat_response_header *stat) +/* This is the standard reply in case we haven't found the dataset. */ +static const pw_response_header notfound = { - stat->pw_poshit = poshit; - stat->pw_posmiss = posmiss; - stat->pw_neghit = neghit; - stat->pw_negmiss = negmiss; - stat->pw_size = modulo; - stat->pw_posttl = postimeout; - stat->pw_negttl = negtimeout; -} - -void -set_pwd_modulo (unsigned long int mod) -{ - modulo = mod; -} + version: NSCD_VERSION, + found: 0, + pw_name_len: 0, + pw_passwd_len: 0, + pw_uid: -1, + pw_gid: -1, + pw_gecos_len: 0, + pw_dir_len: 0, + pw_shell_len: 0 +}; -void -set_pos_pwd_ttl (unsigned long int ttl) +/* This is the struct describing how to write this record. */ +static const struct iovec iov_notfound = { - postimeout = ttl; -} + iov_base: (void *) ¬found, + iov_len: sizeof (notfound) +}; -void -set_neg_pwd_ttl (unsigned long int ttl) -{ - negtimeout = ttl; -} -int -cache_pwdinit () +struct passwddata { - pthread_attr_t attr; - pthread_t thread; - - pwdtbl = calloc (modulo, sizeof (pwdhash)); - if (pwdtbl == NULL) - return -1; - uidtbl = calloc (modulo, sizeof (uidhash)); - if (uidtbl == NULL) - return -1; - negtbl = calloc (modulo, sizeof (neghash)); - if (negtbl == NULL) - return -1; - - pthread_attr_init (&attr); - pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED); - - pthread_create (&thread, NULL, pwdtable_update, &attr); - pthread_create (&thread, NULL, negtable_update, &attr); + pw_response_header resp; + char strdata[0]; +}; - pthread_attr_destroy (&attr); - - return 0; -} - -static struct passwd * -save_pwd (struct passwd *src) -{ - struct passwd *dest; - size_t name_len = strlen (src->pw_name) + 1; - size_t passwd_len = strlen (src->pw_gecos) + 1; - size_t gecos_len = strlen (src->pw_dir) + 1; - size_t dir_len = strlen (src->pw_dir) + 1; - size_t shell_len = strlen (src->pw_shell) + 1; - char *cp; - - dest = malloc (sizeof (struct passwd) - + name_len + passwd_len + gecos_len + dir_len + shell_len); - if (dest == NULL) - return NULL; - - cp = (char *) (dest + 1); - dest->pw_name = cp; - cp = mempcpy (cp, src->pw_name, name_len); - dest->pw_passwd = cp; - cp = mempcpy (cp, src->pw_passwd, passwd_len); - dest->pw_uid = src->pw_uid; - dest->pw_gid = src->pw_gid; - dest->pw_gecos = cp; - cp = mempcpy (cp, src->pw_gecos, gecos_len); - dest->pw_dir = cp; - cp = mempcpy (cp, src->pw_dir, dir_len); - dest->pw_shell = cp; - mempcpy (cp, src->pw_shell, shell_len); - - return dest; -} static void -free_pwd (struct passwd *src) -{ - free (src); -} - -static int -add_cache (struct passwd *pwd) +cache_addpw (struct database *db, int fd, request_header *req, void *key, + struct passwd *pwd) { - pwdhash *work; - uidhash *uidwork; - unsigned long int hash = __nis_hash (pwd->pw_name, - strlen (pwd->pw_name)) % modulo; - - if (debug_flag) - dbg_log (_("pwd_add_cache (%s)"), pwd->pw_name); - - work = &pwdtbl[hash]; - - if (pwdtbl[hash].pwd == NULL) - pwdtbl[hash].pwd = save_pwd (pwd); - else - { - while (work->next != NULL) - work = work->next; - - work->next = calloc (1, sizeof (pwdhash)); - work->next->pwd = save_pwd (pwd); - work = work->next; - } - /* Set a pointer from the pwuid hash table to the pwname hash table */ - time (&work->create); - uidwork = &uidtbl[pwd->pw_uid % modulo]; - if (uidwork->pwptr == NULL) - uidwork->pwptr = work->pwd; - else - { - while (uidwork->next != NULL) - uidwork = uidwork->next; - - uidwork->next = calloc (1, sizeof (uidhash)); - uidwork->next->pwptr = work->pwd; - } - return 0; -} - -static struct passwd * -cache_search_name (const char *name) -{ - pwdhash *work; - unsigned long int hash = __nis_hash (name, strlen (name)) % modulo; - - work = &pwdtbl[hash]; + ssize_t total; + ssize_t written; + time_t t = time (NULL); - while (work->pwd != NULL) + if (pwd == NULL) { - if (strcmp (work->pwd->pw_name, name) == 0) - return work->pwd; - if (work->next != NULL) - work = work->next; - else - return NULL; - } - return NULL; -} + /* We have no data. This means we send the standard reply for this + case. */ + void *copy; -static struct passwd * -cache_search_uid (uid_t uid) -{ - uidhash *work; + total = sizeof (notfound); - work = &uidtbl[uid % modulo]; + written = writev (fd, &iov_notfound, 1); - while (work->pwptr != NULL) - { - if (work->pwptr->pw_uid == uid) - return work->pwptr; - if (work->next != NULL) - work = work->next; - else - return NULL; - } - return NULL; -} + copy = malloc (req->key_len); + if (copy == NULL) + error (EXIT_FAILURE, errno, _("while allocating key copy")); + memcpy (copy, key, req->key_len); -static int -add_negcache (char *key) -{ - neghash *work; - unsigned long int hash = __nis_hash (key, strlen (key)) % modulo; + /* Compute the timeout time. */ + t += db->negtimeout; - if (debug_flag) - dbg_log (_("pwd_add_netgache (%s|%ld)"), key, hash); + /* Now get the lock to safely insert the records. */ + pthread_rwlock_rdlock (&db->lock); - work = &negtbl[hash]; + cache_add (req->type, copy, req->key_len, &iov_notfound, + sizeof (notfound), (void *) -1, 0, t, db); - if (negtbl[hash].key == NULL) - { - negtbl[hash].key = strdup (key); - negtbl[hash].next = NULL; + pthread_rwlock_unlock (&db->lock); } else { - while (work->next != NULL) - work = work->next; - - work->next = calloc (1, sizeof (neghash)); - work->next->key = strdup (key); - work = work->next; + /* Determine the I/O structure. */ + struct passwddata *data; + size_t pw_name_len = strlen (pwd->pw_name) + 1; + size_t pw_passwd_len = strlen (pwd->pw_passwd) + 1; + size_t pw_gecos_len = strlen (pwd->pw_gecos) + 1; + size_t pw_dir_len = strlen (pwd->pw_dir) + 1; + size_t pw_shell_len = strlen (pwd->pw_shell) + 1; + char *cp; + char buf[12]; + ssize_t n; + + /* We need this to insert the `byuid' entry. */ + n = snprintf (buf, sizeof (buf), "%d", pwd->pw_uid) + 1; + + /* We allocate all data in one memory block: the iov vector, + the response header and the dataset itself. */ + total = (sizeof (struct passwddata) + pw_name_len + pw_passwd_len + + pw_gecos_len + pw_dir_len + pw_shell_len); + data = (struct passwddata *) malloc (total + n); + if (data == NULL) + /* There is no reason to go on. */ + error (EXIT_FAILURE, errno, _("while allocating cache entry")); + + data->resp.found = 1; + data->resp.pw_name_len = pw_name_len; + data->resp.pw_passwd_len = pw_passwd_len; + data->resp.pw_uid = pwd->pw_uid; + data->resp.pw_gid = pwd->pw_gid; + data->resp.pw_gecos_len = pw_gecos_len; + data->resp.pw_dir_len = pw_dir_len; + data->resp.pw_shell_len = pw_shell_len; + + cp = data->strdata; + + /* Copy the strings over into the buffer. */ + cp = mempcpy (cp, pwd->pw_name, pw_name_len); + cp = mempcpy (cp, pwd->pw_passwd, pw_passwd_len); + cp = mempcpy (cp, pwd->pw_gecos, pw_gecos_len); + cp = mempcpy (cp, pwd->pw_dir, pw_dir_len); + cp = mempcpy (cp, pwd->pw_shell, pw_shell_len); + + /* Finally the stringified UID value. */ + memcpy (cp, buf, n); + + /* We write the dataset before inserting it to the database + since while inserting this thread might block and so would + unnecessarily let the receiver wait. */ + written = write (fd, &data->resp, total); + + /* Compute the timeout time. */ + t += db->postimeout; + + /* Now get the lock to safely insert the records. */ + pthread_rwlock_rdlock (&db->lock); + + /* We have to add the value for both, byname and byuid. */ + cache_add (GETPWBYNAME, data->strdata, pw_name_len, data, + total, data, 0, t, db); + + cache_add (GETPWBYUID, cp, n, data, total, data, 1, t, db); + + pthread_rwlock_unlock (&db->lock); } - time (&work->create); - - return 0; -} - -static int -cache_search_neg (const char *key) -{ - neghash *work; - unsigned long int hash = __nis_hash (key, strlen (key)) % modulo; - - if (debug_flag) - dbg_log (_("pwd_cache_search_neg (%s|%ld)"), key, hash); - - work = &negtbl[hash]; - - while (work->key != NULL) + if (written != total) { - if (strcmp (work->key, key) == 0) - return 1; - if (work->next != NULL) - work = work->next; - else - return 0; + char buf[256]; + dbg_log (_("short write in %s: %s"), __FUNCTION__, + strerror_r (errno, buf, sizeof (buf))); } - return 0; } -void * -cache_getpwnam (void *v_param) -{ - struct passwd *pwd; - param_t *param = (param_t *)v_param; - - pthread_rwlock_rdlock (&pwdlock); - pwd = cache_search_name (param->key); - /* I don't like it to hold the read only lock longer, but it is - necessary to avoid to much malloc/free/strcpy. */ - - if (pwd != NULL) - { - if (debug_flag) - dbg_log (_("Found \"%s\" in cache !"), param->key); +void +addpwbyname (struct database *db, int fd, request_header *req, void *key) +{ + /* Search for the entry matching the key. Please note that we don't + look again in the table whether the dataset is now available. We + simply insert it. It does not matter if it is in there twice. The + pruning function only will look at the timestamp. */ + int buflen = 256; + char *buffer = alloca (buflen); + struct passwd resultbuf; + struct passwd *pwd; - ++poshit; - pw_send_answer (param->conn, pwd); - close_socket (param->conn); + if (debug_level > 0) + dbg_log (_("Haven't found \"%s\" in password cache!"), key); - pthread_rwlock_unlock (&pwdlock); - } - else + while (getpwnam_r (key, &resultbuf, buffer, buflen, &pwd) != 0 + && errno == ERANGE) { - int status; - int buflen = 1024; - char *buffer = calloc (1, buflen); - struct passwd resultbuf; - - if (debug_flag) - dbg_log (_("Doesn't found \"%s\" in cache !"), param->key); - - pthread_rwlock_unlock (&pwdlock); - - pthread_rwlock_rdlock (&neglock); - status = cache_search_neg (param->key); - pthread_rwlock_unlock (&neglock); - - if (status == 0) - { - while (buffer != NULL - && (getpwnam_r (param->key, &resultbuf, buffer, buflen, &pwd) - != 0) - && errno == ERANGE) - { - errno = 0; - buflen += 1024; - buffer = realloc (buffer, buflen); - } - - if (buffer != NULL && pwd != NULL) - { - struct passwd *tmp; - - ++posmiss; - pthread_rwlock_wrlock (&pwdlock); - /* While we are waiting on the lock, somebody else could - add this entry. */ - tmp = cache_search_name (param->key); - if (tmp == NULL) - add_cache (pwd); - pthread_rwlock_unlock (&pwdlock); - } - else - { - ++negmiss; - pthread_rwlock_wrlock (&neglock); - add_negcache (param->key); - pthread_rwlock_unlock (&neglock); - } - } - else - ++neghit; - pw_send_answer (param->conn, pwd); - close_socket (param->conn); - if (buffer != NULL) - free (buffer); + errno = 0; + buflen += 256; + buffer = alloca (buflen); } - free (param->key); - free (param); - return NULL; -} - -void * -cache_pw_disabled (void *v_param) -{ - param_t *param = (param_t *)v_param; - - if (debug_flag) - dbg_log (_("\tpasswd cache is disabled\n")); - pw_send_disabled (param->conn); - return NULL; + cache_addpw (db, fd, req, key, pwd); } -void * -cache_getpwuid (void *v_param) -{ - param_t *param = (param_t *)v_param; - struct passwd *pwd, resultbuf; - uid_t uid = strtol (param->key, NULL, 10); - - pthread_rwlock_rdlock (&pwdlock); - pwd = cache_search_uid (uid); - - /* I don't like it to hold the read only lock longer, but it is - necessary to avoid to much malloc/free/strcpy. */ - if (pwd != NULL) - { - if (debug_flag) - dbg_log (_("Found \"%d\" in cache !"), uid); - - ++poshit; - pw_send_answer (param->conn, pwd); - close_socket (param->conn); - - pthread_rwlock_unlock (&pwdlock); - } - else - { - int buflen = 1024; - char *buffer = malloc (buflen); - int status; - - if (debug_flag) - dbg_log (_("Doesn't found \"%d\" in cache !"), uid); - - pthread_rwlock_unlock (&pwdlock); - - pthread_rwlock_rdlock (&neglock); - status = cache_search_neg (param->key); - pthread_rwlock_unlock (&neglock); - - if (status == 0) - { - while (buffer != NULL - && (getpwuid_r (uid, &resultbuf, buffer, buflen, &pwd) != 0) - && errno == ERANGE) - { - errno = 0; - buflen += 1024; - buffer = realloc (buffer, buflen); - } - - if (buffer != NULL && pwd != NULL) - { - struct passwd *tmp; - - ++posmiss; - pthread_rwlock_wrlock (&pwdlock); - /* While we are waiting on the lock, somebody else could - add this entry. */ - tmp = cache_search_uid (uid); - if (tmp == NULL) - add_cache (pwd); - pthread_rwlock_unlock (&pwdlock); - } - else - { - ++negmiss; - pthread_rwlock_wrlock (&neglock); - add_negcache (param->key); - pthread_rwlock_unlock (&neglock); - } - } - else - ++neghit; - - pw_send_answer (param->conn, pwd); - close_socket (param->conn); - if (buffer != NULL) - free (buffer); - } - free (param->key); - free (param); - return NULL; -} - -static void * -pwdtable_update (void *v) -{ - time_t now; - int i; +void +addpwbyuid (struct database *db, int fd, request_header *req, void *key) +{ + /* Search for the entry matching the key. Please note that we don't + look again in the table whether the dataset is now available. We + simply insert it. It does not matter if it is in there twice. The + pruning function only will look at the timestamp. */ + int buflen = 256; + char *buffer = alloca (buflen); + struct passwd resultbuf; + struct passwd *pwd; + uid_t uid = atol (key); - sleep (20); + if (debug_level > 0) + dbg_log (_("Haven't found \"%d\" in password cache!"), uid); - while (!do_shutdown) + while (getpwuid_r (uid, &resultbuf, buffer, buflen, &pwd) != 0 + && errno == ERANGE) { - if (debug_flag > 2) - dbg_log (_("(pwdtable_update) Wait for write lock!")); - - pthread_rwlock_wrlock (&pwdlock); - - if (debug_flag > 2) - dbg_log (_("(pwdtable_update) Have write lock")); - - time (&now); - for (i = 0; i < modulo; ++i) - { - pwdhash *work = &pwdtbl[i]; - - while (work && work->pwd) - { - if ((now - work->create) >= postimeout) - { - uidhash *uh = &uidtbl[work->pwd->pw_uid % modulo]; - - if (debug_flag) - dbg_log (_("Give \"%s\" free"), work->pwd->pw_name); - - while (uh != NULL && uh->pwptr) - { - if (uh->pwptr->pw_uid == work->pwd->pw_uid) - { - if (debug_flag) - dbg_log (_("Give uid for \"%s\" free"), - work->pwd->pw_name); - if (uh->next != NULL) - { - uidhash *tmp = uh->next; - uh->pwptr = tmp->pwptr; - uh->next = tmp->next; - free (tmp); - } - else - uh->pwptr = NULL; - } - uh = uh->next; - } - - free_pwd (work->pwd); - if (work->next != NULL) - { - pwdhash *tmp = work->next; - work->create = tmp->create; - work->next = tmp->next; - work->pwd = tmp->pwd; - free (tmp); - } - else - work->pwd = NULL; - } - work = work->next; - } - } - if (debug_flag > 2) - dbg_log (_("(pwdtable_update) Release wait lock")); - pthread_rwlock_unlock (&pwdlock); - sleep (20); + errno = 0; + buflen += 256; + buffer = alloca (buflen); } - return NULL; -} - -static void * -negtable_update (void *v) -{ - time_t now; - int i; - sleep (30); - - while (!do_shutdown) - { - if (debug_flag > 2) - dbg_log (_("(negpwdtable_update) Wait for write lock!")); - - pthread_rwlock_wrlock (&neglock); - - if (debug_flag > 2) - dbg_log (_("(negpwdtable_update) Have write lock")); - - time (&now); - for (i = 0; i < modulo; ++i) - { - neghash *work = &negtbl[i]; - - while (work && work->key) - { - if ((now - work->create) >= negtimeout) - { - if (debug_flag) - dbg_log (_("Give \"%s\" free"), work->key); - - free (work->key); - - if (work->next != NULL) - { - neghash *tmp = work->next; - work->create = tmp->create; - work->next = tmp->next; - work->key = tmp->key; - free (tmp); - } - else - work->key = NULL; - } - work = work->next; - } - } - if (debug_flag > 2) - dbg_log (_("(negpwdtable_update) Release wait lock")); - - pthread_rwlock_unlock (&neglock); - sleep (10); - } - return NULL; + cache_addpw (db, fd, req, key, pwd); } |