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-rw-r--r--nscd/pwdcache.c581
1 files changed, 581 insertions, 0 deletions
diff --git a/nscd/pwdcache.c b/nscd/pwdcache.c
new file mode 100644
index 0000000000..a3676666da
--- /dev/null
+++ b/nscd/pwdcache.c
@@ -0,0 +1,581 @@
+/* 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.
+
+   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 <errno.h>
+#include <malloc.h>
+#include <pthread.h>
+#include <pwd.h>
+#include <string.h>
+#include <rpcsvc/nis.h>
+#include <sys/types.h>
+
+#include "dbg_log.h"
+#include "nscd.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 pwdhash *pwptr;
+};
+typedef struct uidhash uidhash;
+
+struct neghash
+{
+  time_t create;
+  struct neghash *next;
+  char *key;
+};
+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)
+{
+  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;
+}
+
+void
+set_pos_pwd_ttl (unsigned long int ttl)
+{
+  postimeout = ttl;
+}
+
+void
+set_neg_pwd_ttl (unsigned long int ttl)
+{
+  negtimeout = ttl;
+}
+
+int
+cache_pwdinit ()
+{
+  pthread_t thread;
+
+  pwdtbl = calloc (modulo, sizeof (pwdhash));
+  if (pwdtbl == NULL)
+    return -1;
+  uidtbl = calloc (modulo, sizeof (pwdhash));
+  if (uidtbl == NULL)
+    return -1;
+  negtbl = calloc (modulo, sizeof (neghash));
+  if (negtbl == NULL)
+    return -1;
+
+  pthread_create (&thread, NULL, pwdtable_update, (void *)NULL);
+  pthread_detach (thread);
+  pthread_create (&thread, NULL, negtable_update, (void *)NULL);
+  pthread_detach (thread);
+  return 0;
+}
+
+static struct passwd *
+save_pwd (struct passwd *src)
+{
+  struct passwd *dest;
+
+  dest = calloc (1, sizeof (struct passwd));
+  dest->pw_name = strdup (src->pw_name);
+  dest->pw_passwd = strdup (src->pw_passwd);
+  dest->pw_uid = src->pw_uid;
+  dest->pw_gid = src->pw_gid;
+  dest->pw_gecos = strdup (src->pw_gecos);
+  dest->pw_dir = strdup (src->pw_dir);
+  dest->pw_shell = strdup (src->pw_shell);
+
+  return dest;
+}
+
+static void
+free_pwd (struct passwd *src)
+{
+  free (src->pw_name);
+  free (src->pw_passwd);
+  free (src->pw_gecos);
+  free (src->pw_dir);
+  free (src->pw_shell);
+  free (src);
+}
+
+static int
+add_cache (struct passwd *pwd)
+{
+  pwdhash *work;
+  unsigned long int hash = __nis_hash (pwd->pw_name,
+				       strlen (pwd->pw_name)) % modulo;
+
+  if (debug_flag)
+    dbg_log (_("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);
+  uidtbl[pwd->pw_uid % modulo].pwptr = work;
+
+  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];
+
+  while (work->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;
+}
+
+static struct passwd *
+cache_search_uid (uid_t uid)
+{
+  uidhash *work;
+
+  work = &uidtbl[uid % modulo];
+
+  while (work->pwptr != NULL)
+    {
+      if (work->pwptr->pwd->pw_uid == uid)
+	return work->pwptr->pwd;
+      if (work->next != NULL)
+	work = work->next;
+      else
+	return NULL;
+    }
+  return NULL;
+}
+
+static int
+add_negcache (char *key)
+{
+  neghash *work;
+  unsigned long int hash = __nis_hash (key, strlen (key)) % modulo;
+
+  if (debug_flag)
+    dbg_log (_("add_netgache (%s|%ld)"), key, hash);
+
+  work = &negtbl[hash];
+
+  if (negtbl[hash].key == NULL)
+    {
+      negtbl[hash].key = strdup (key);
+      negtbl[hash].next = NULL;
+    }
+  else
+    {
+      while (work->next != NULL)
+	work = work->next;
+
+      work->next = calloc (1, sizeof (neghash));
+      work->next->key = strdup (key);
+      work = work->next;
+    }
+  /* Set a pointer from the pwuid hash table to the pwname hash table */
+  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;
+
+  work = &negtbl[hash];
+
+  if (debug_flag)
+    dbg_log (_("cache_search_neg (%s|%ld)"), key, hash);
+
+  while (work->key != NULL)
+    {
+      if (strcmp (work->key, key) == 0)
+	return 1;
+      if (work->next != NULL)
+	work = work->next;
+      else
+	return 0;
+    }
+  return 0;
+}
+
+void *
+cache_getpwnam (void *v_param)
+{
+  param_t *param = (param_t *)v_param;
+  struct passwd *pwd, resultbuf;
+
+  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);
+
+      ++poshit;
+      pw_send_answer (param->conn, pwd);
+      close_socket (param->conn);
+
+      pthread_rwlock_unlock (&pwdlock);
+      pwd = &resultbuf;
+    }
+  else
+    {
+      int status;
+      int buflen = 1024;
+      char *buffer = malloc (buflen);
+
+      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);
+    }
+  free (param->key);
+  free (param);
+  return NULL;
+}
+
+void *
+cache_pw_disabled (void *v_param)
+{
+  param_t *param = (param_t *)v_param;
+
+  pw_send_disabled (param->conn);
+  return NULL;
+}
+
+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;
+}
+
+void *
+pwdtable_update (void *v)
+{
+  time_t now;
+  int i;
+
+  sleep (20);
+
+  while (!do_shutdown)
+    {
+      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->pwd->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);
+    }
+  return NULL;
+}
+
+void *
+negtable_update (void *v)
+{
+  time_t now;
+  int i;
+
+  sleep (30);
+
+  while (!do_shutdown)
+    {
+      if (debug_flag > 2)
+	dbg_log (_("(negtable_update) Wait for write lock!"));
+
+      pthread_rwlock_wrlock (&neglock);
+
+      if (debug_flag)
+	dbg_log (_("(negtable_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)
+	dbg_log (_("(negtable_update) Release wait lock"));
+
+      pthread_rwlock_unlock (&neglock);
+      sleep (10);
+    }
+  return NULL;
+}