Cookies are no longer persistent

src/Makefile.am

@@ -19,7 +19,7 @@ ocserv_SOURCES = main.c main-auth.c worker-vpn.c worker-auth.c tlslib.c \
 	vpn.h cookies.h tlslib.h http-parser/http_parser.h log.c tun.c tun.h \
 	config.c pam.c pam.h worker-resume.c worker.h main-resume.c main.h \
 	worker-extras.c main-auth.h \
-	main-user.c cookies-gdbm.c cookies-hash.c worker-misc.c setproctitle.h \
+	main-user.c worker-misc.c setproctitle.h \
 	setproctitle.c worker-privs.c plain.c plain.h common.h common.c \
 	sec-mod.c sec-mod.h script-list.h system.c system.h icmp-ping.c icmp-ping.h \
 	str.c str.h gettime.h $(CCAN_SOURCES)

src/config.c

@@ -191,8 +191,6 @@ unsigned j;
 	READ_STRING("tls-priorities", config->priorities, 0);
 	READ_STRING("chroot-dir", config->chroot_dir, 0);
 
-	READ_STRING("cookie-db", config->cookie_db_name, 0);
-
 	READ_NUMERIC("cookie-validity", config->cookie_validity, 1);
 	READ_NUMERIC("auth-timeout", config->auth_timeout, 0);
 	READ_NUMERIC("max-clients", config->max_clients, 0);
@@ -376,7 +374,6 @@ unsigned i;
 	DEL(config->cert_group_oid);
 	DEL(config->priorities);
 	DEL(config->chroot_dir);
-	DEL(config->cookie_db_name);
 	DEL(config->connect_script);
 	DEL(config->disconnect_script);
 

src/cookies-gdbm.c

@@ -1,190 +0,0 @@
-/*
- * Copyright (C) 2013 Nikos Mavrogiannopoulos
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program 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 General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-#include <config.h>
-
-#include <gnutls/gnutls.h>
-#include <gnutls/crypto.h>
-#include <errno.h>
-#include <stdlib.h>
-#include <stdarg.h>
-#include <stdio.h>
-#include <string.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <limits.h>
-#include <sys/stat.h>
-#include "setproctitle.h"
-#include <main.h>
-#include <cookies.h>
-
-#ifdef HAVE_GDBM
-
-# include <gdbm.h>
-
-/* Note that it receives allocated data and stores them. Do not
- * free the sc.
- */
-static
-int cookie_gdbm_store(main_server_st *s, struct stored_cookie_st* sc)
-{
-GDBM_FILE dbf;
-datum key;
-datum data;
-int ret;
-
-	dbf = gdbm_open((char*)s->config->cookie_db_name, 0, GDBM_WRCREAT, S_IRUSR|S_IWUSR, NULL);
-	if (dbf == NULL) {
-		syslog(LOG_ERR, "Cannot open cookie database: %s", s->config->cookie_db_name);
-		return -1;
-	}
-
-	key.dptr = (void*)sc->cookie;
-	key.dsize = sizeof(sc->cookie);
-	data.dptr = (void*)sc;
-	data.dsize = sizeof(*sc);
-
-	ret = gdbm_store( dbf, key, data, GDBM_INSERT);
-	if (ret != 0) {
-		ret = -1;
-		goto finish;
-	}
-
-	ret = 0;
-
-finish:
-	free(sc);
-	gdbm_close(dbf);
-	return ret;
-}
-
-/* retrieves and deletes the entry */
-static
-int cookie_gdbm_retrieve(main_server_st *s, const void* cookie, unsigned cookie_size, 
-			struct stored_cookie_st* sc)
-{
-GDBM_FILE dbf;
-datum key;
-datum data;
-int ret;
-
-	dbf = gdbm_open((char*)s->config->cookie_db_name, 0, GDBM_READER, 0, NULL);
-	if (dbf == NULL) {
-		syslog(LOG_ERR, "Cannot open cookie database: %s", s->config->cookie_db_name);
-		return -1;
-	}
-
-	key.dptr = (void*)cookie;
-	key.dsize = cookie_size;
-
-	data = gdbm_fetch( dbf, key);
-	if (data.dsize != sizeof(*sc)) {
-		ret = -1;
-		goto finish;
-	}
-	memcpy(sc, data.dptr, data.dsize);
-	gdbm_delete(dbf, key);
-
-	ret = 0;
-
-finish:
-	gdbm_close(dbf);
-	return ret;
-}
-
-static
-void cookie_gdbm_expire(main_server_st* s)
-{
-GDBM_FILE dbf;
-datum key;
-datum data;
-int deleted = 0;
-struct stored_cookie_st sc;
-time_t now = time(0);
-pid_t pid;
-
-	pid = fork();
-	if (pid == 0) { /* child */
-		clear_lists(s);
-		setproctitle(PACKAGE_NAME"-maint");
-
-		dbf = gdbm_open((char*)s->config->cookie_db_name, 0, GDBM_WRITER, 0, NULL);
-		if (dbf == NULL)
-			exit(1);
-
-		key = gdbm_firstkey(dbf);
-		if (key.dptr == NULL)
-			goto finish;
-
-		while(key.dptr != NULL) {
-			data = gdbm_fetch( dbf, key);
-			if (data.dsize != sizeof(sc)) {
-				gdbm_delete(dbf, key);
-				deleted++;
-			} else {
-				memcpy(&sc, data.dptr, data.dsize);
-				if (sc.expiration <= now) {
-					gdbm_delete(dbf, key);
-					deleted++;
-				}
-			}
-
-			key = gdbm_nextkey(dbf, key);
-		}
-	
-		if (deleted > 0)
-			gdbm_reorganize(dbf);
-
-finish:
-		gdbm_close(dbf);
-		exit(0);
-	}
-	
-	return;
-}
-
-static
-int cookie_gdbm_init(main_server_st* s)
-{
-	return 0;
-}
-
-static
-void cookie_gdbm_erase(main_server_st* s)
-{
-	return;
-}
-
-static
-void cookie_gdbm_deinit(main_server_st* s)
-{
-        return;
-}
-
-struct cookie_storage_st gdbm_cookie_funcs = {
-	.store = cookie_gdbm_store,
-	.retrieve = cookie_gdbm_retrieve,
-	.expire = cookie_gdbm_expire,
-	.init = cookie_gdbm_init,
-	.deinit = cookie_gdbm_deinit,
-	.erase = cookie_gdbm_erase,
-};
-
-#endif

src/cookies-hash.c

@@ -1,199 +0,0 @@
-/*
- * Copyright (C) 2013 Nikos Mavrogiannopoulos
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program 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 General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-#include <config.h>
-
-#include <gnutls/gnutls.h>
-#include <gnutls/crypto.h>
-#include <errno.h>
-#include <stdlib.h>
-#include <stdarg.h>
-#include <stdio.h>
-#include <string.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <limits.h>
-#include <sys/stat.h>
-
-#include <main.h>
-#include <cookies.h>
-#include <ccan/htable/htable.h>
-#include <ccan/hash/hash.h>
-
-#define MAX_COOKIES(n) ((n>0&&n>64)?(2*n):128)
-
-/* Note that it receives allocated data and stores them. Do not
- * free the sc.
- */
-static
-int store_cookie_hash(main_server_st *s, struct stored_cookie_st* sc)
-{
-size_t key;
-
-	if (s->cookie_db->entries >= MAX_COOKIES(s->config->max_clients)) {
-		mslog(s, NULL, LOG_INFO, "maximum number of cookies was reached (%u)", MAX_COOKIES(s->config->max_clients));
-		need_maintainance = 1;
-		return -1;
-	}
-
-	key = hash_stable_8(sc->cookie, COOKIE_SIZE, 0);
-
-	htable_add(&s->cookie_db->ht, key, sc);
-	s->cookie_db->entries++;
-
-	return 0;
-}
-
-/* retrieves and deletes the entry */
-static
-int retrieve_cookie_hash(main_server_st *s, const void* cookie, unsigned cookie_size, 
-			struct stored_cookie_st* rsc)
-{
-size_t key;
-struct htable_iter iter;
-struct stored_cookie_st * sc;
-
-	key = hash_stable_8(cookie, cookie_size, 0);
-
-	sc = htable_firstval(&s->cookie_db->ht, &iter, key);
-	while(sc != NULL) {
-		if (cookie_size == COOKIE_SIZE &&
-	          memcmp (cookie, sc->cookie, COOKIE_SIZE) == 0) {
-
-			memcpy(rsc, sc, sizeof(*sc));
-			htable_delval(&s->cookie_db->ht, &iter);
-	          	return 0;
-		}
-
-          	sc = htable_nextval(&s->cookie_db->ht, &iter, key);
-        }
-
-	return -1;
-}
-
-static void delete_entry(hash_db_st *cookie_db, struct htable_iter *iter,
-	struct stored_cookie_st *sc)
-{
-       	htable_delval(&cookie_db->ht, iter);
-       	free(sc);
-       	cookie_db->entries--;
-}
-
-static
-void expire_cookies_hash(main_server_st* s)
-{
-struct stored_cookie_st *sc;
-struct htable_iter iter;
-time_t now = time(0);
-unsigned int todelete;
-
-	sc = htable_first(&s->cookie_db->ht, &iter);
-	while(sc != NULL) {
-		if (sc->expiration <= now) {
-			delete_entry(s->cookie_db, &iter, sc);
-		}
-          	sc = htable_next(&s->cookie_db->ht, &iter);
-        }
-
-        /* if the hash is still full then delete the few first cookies */
-	if (s->cookie_db->entries >= MAX_COOKIES(s->config->max_clients)) {
-		todelete = MAX_COOKIES(s->config->max_clients)/5;
-		mslog(s, NULL, LOG_INFO, "too many cookies present; expiring the first %u", todelete);
-		sc = htable_first(&s->cookie_db->ht, &iter);
-		while(sc != NULL) {
-			if (todelete >= 0) {
-				delete_entry(s->cookie_db, &iter, sc);
-				todelete--;
-			} else {
-				break;
-			}
-        	  	sc = htable_next(&s->cookie_db->ht, &iter);
-	        }
-	}
-}
-
-static
-void erase_cookies_hash(main_server_st* s)
-{
-struct stored_cookie_st *sc;
-struct htable_iter iter;
-time_t now = time(0);
-
-	sc = htable_first(&s->cookie_db->ht, &iter);
-	while(sc != NULL) {
-		if (sc->expiration <= now) {
-	          	htable_delval(&s->cookie_db->ht, &iter);
-	          	memset(sc->cookie, 0, sizeof(sc->cookie));
-	          	free(sc);
-			s->cookie_db->entries--;
-		}
-          	sc = htable_next(&s->cookie_db->ht, &iter);
-        }
-}
-
-static size_t rehash(const void *_e, void *unused)
-{
-const struct stored_cookie_st *e = _e;
-
-	return hash_stable_8(e->cookie, COOKIE_SIZE, 0);
-}
-
-static
-int cookie_db_init_hash(main_server_st * s)
-{
-hash_db_st * db;
-
-	db = malloc(sizeof(*db));
-	if (db == NULL)
-		return -1;
-
-	htable_init(&db->ht, rehash, NULL);
-	db->entries = 0;
-
-	s->cookie_db = db;
-	
-	return 0;
-}
-
-static
-void cookie_db_deinit_hash(main_server_st* s)
-{
-struct stored_cookie_st* cache;
-struct htable_iter iter;
-
-	cache = htable_first(&s->cookie_db->ht, &iter);
-	while(cache != NULL) {
-          	free(cache);
-          	cache = htable_next(&s->cookie_db->ht, &iter);
-        }
-        htable_clear(&s->cookie_db->ht);
-	s->cookie_db->entries = 0;
-
-        return;
-}
-
-struct cookie_storage_st hash_cookie_funcs = {
-	.store = store_cookie_hash,
-	.retrieve = retrieve_cookie_hash,
-	.expire = expire_cookies_hash,
-	.erase = erase_cookies_hash,
-	.init = cookie_db_init_hash,
-	.deinit = cookie_db_deinit_hash,
-};

src/cookies.c

@@ -35,28 +35,91 @@
 #include <main.h>
 #include <cookies.h>
 
-cookie_store_fn store_cookie;
+int decrypt_cookie(main_server_st * s, const uint8_t* cookie, unsigned cookie_size, 
-cookie_retrieve_fn retrieve_cookie;
+			struct stored_cookie_st* sc)
-cookie_db_deinit_fn cookie_db_deinit;
-cookie_expire_fn expire_cookies;
-cookie_expire_fn erase_cookies;
-
-int cookie_db_init(main_server_st* s)
 {
-struct cookie_storage_st* funcs;
+gnutls_datum_t iv = { (void*)cookie, COOKIE_IV_SIZE };
+int ret;
+uint8_t tag[COOKIE_MAC_SIZE];
+gnutls_cipher_hd_t h;
+gnutls_datum_t key = { (void*)s->cookie_key, sizeof(s->cookie_key) };
 
-#ifdef HAVE_GDBM
+	if (cookie_size != COOKIE_SIZE)
-	if (s->config->cookie_db_name != NULL)
+		return -1;
-		funcs = &gdbm_cookie_funcs;
-	else
-#endif
-		funcs = &hash_cookie_funcs;
 
-	cookie_db_deinit = funcs->deinit;
+	ret = gnutls_cipher_init(&h, GNUTLS_CIPHER_AES_128_GCM, &key, &iv);
-	expire_cookies = funcs->expire;
+	if (ret < 0)
-	erase_cookies = funcs->erase;
+		return -1;
-	store_cookie = funcs->store;
+	
-	retrieve_cookie = funcs->retrieve;
+	cookie += COOKIE_IV_SIZE;
+	
+	ret = gnutls_cipher_decrypt2(h, cookie, sizeof(*sc), sc, sizeof(*sc));
+	if (ret < 0) {
+		ret = -1;
+		goto cleanup;
+	}
+	
+	ret = gnutls_cipher_tag(h, tag, sizeof(tag));
+	if (ret < 0) {
+		ret = -1;
+		goto cleanup;
+	}
+	
+	cookie += sizeof(*sc);
+	if (memcmp(tag, cookie, COOKIE_MAC_SIZE) != 0) {
+		ret = -1;
+		goto cleanup;
+	}
+
+	ret = 0;
+
+cleanup:
+	gnutls_cipher_deinit(h);
+	
+	return ret;
+}
+
+int encrypt_cookie(main_server_st * s, uint8_t* cookie, unsigned cookie_size, 
+			const struct stored_cookie_st* sc)
+{
+uint8_t _iv[COOKIE_IV_SIZE];
+gnutls_cipher_hd_t h;
+gnutls_datum_t iv = { _iv, sizeof(_iv) };
+gnutls_datum_t key = { (void*)s->cookie_key, sizeof(s->cookie_key) };
+int ret;
+
+	if (cookie_size != COOKIE_SIZE)
+		return -1;
+	
+	ret = gnutls_rnd(GNUTLS_RND_NONCE, _iv, sizeof(_iv));
+	if (ret < 0)
+		return -1;
+	
+	ret = gnutls_cipher_init(&h, GNUTLS_CIPHER_AES_128_GCM, &key, &iv);
+	if (ret < 0)
+		return -1;
+
+	memcpy(cookie, _iv, COOKIE_IV_SIZE);
+	cookie += COOKIE_IV_SIZE;
+	
+	ret = gnutls_cipher_encrypt2(h, sc, sizeof(*sc), cookie, sizeof(*sc));
+	if (ret < 0) {
+		ret = -1;
+		goto cleanup;
+	}
+	
+	cookie += sizeof(*sc);
+	
+	ret = gnutls_cipher_tag(h, cookie, COOKIE_MAC_SIZE);
+	if (ret < 0) {
+		ret = -1;
+		goto cleanup;
+	}
+	
+	ret = 0;
+	
+cleanup:
+	gnutls_cipher_deinit(h);
+	return ret;
 
-	return funcs->init(s);
 }

src/cookies.h

@@ -2,44 +2,22 @@
 #define COOKIES_H
 
 #include <vpn.h>
-#include <main.h>
 
-struct stored_cookie_st {
+struct __attribute__ ((__packed__)) stored_cookie_st {
-	uint8_t cookie[COOKIE_SIZE];
 	char username[MAX_USERNAME_SIZE];
 	char groupname[MAX_GROUPNAME_SIZE];
 	char hostname[MAX_HOSTNAME_SIZE];
 	uint8_t session_id[GNUTLS_MAX_SESSION_ID];
-	time_t expiration;
+	uint32_t expiration;
 };
 
-typedef int (*cookie_store_fn)(main_server_st *, struct stored_cookie_st* sc);
+#define COOKIE_IV_SIZE 12 /* AES-GCM */
+#define COOKIE_MAC_SIZE 12 /* 96-bits of AES-GCM */
+#define COOKIE_SIZE (COOKIE_IV_SIZE + sizeof(struct stored_cookie_st) + COOKIE_MAC_SIZE)
 
-typedef int (*cookie_retrieve_fn)(main_server_st *, const void* cookie, unsigned cookie_size, 
+int encrypt_cookie(struct main_server_st * s, uint8_t* cookie, unsigned cookie_size, 
+			const struct stored_cookie_st* sc);
+int decrypt_cookie(struct main_server_st * s, const uint8_t* cookie, unsigned cookie_size, 
 			struct stored_cookie_st* sc);
 
-typedef void (*cookie_db_deinit_fn)(main_server_st*);
-typedef void (*cookie_expire_fn)(main_server_st* s);
-
-extern cookie_store_fn store_cookie;
-extern cookie_retrieve_fn retrieve_cookie;
-extern cookie_db_deinit_fn cookie_db_deinit;
-extern cookie_expire_fn expire_cookies;
-extern cookie_expire_fn erase_cookies;
-
-int cookie_db_init(main_server_st*);
-
-
-struct cookie_storage_st {
-	cookie_store_fn store;
-	cookie_retrieve_fn retrieve;
-	cookie_expire_fn expire;
-	cookie_expire_fn erase; /* erases cookies if stored in process */
-	int (*init)(main_server_st *);
-	cookie_db_deinit_fn deinit;
-};
-
-extern struct cookie_storage_st gdbm_cookie_funcs;
-extern struct cookie_storage_st hash_cookie_funcs;
-
 #endif

src/ipc.h

@@ -9,6 +9,7 @@
 #include <net/if.h>
 #include <vpn.h>
 #include <tlslib.h>
+#include <cookies.h>
 
 #define MAX_MSG_SIZE 256
 

src/log.c

@@ -27,6 +27,7 @@
 
 #include <vpn.h>
 #include <worker.h>
+#include <main.h>
 
 const char *human_addr(const struct sockaddr *sa, socklen_t salen,
 		       void *_buf, size_t buflen)

src/main-auth.c

@@ -155,31 +155,27 @@ int handle_auth_cookie_req(main_server_st* s, struct proc_st* proc,
  			   const struct cmd_auth_cookie_req_st * req)
 {
 int ret;
-struct stored_cookie_st *sc;
+struct stored_cookie_st sc;
 time_t now = time(0);
 
-	sc = malloc(sizeof(*sc));
+	ret = decrypt_cookie(s, req->cookie, sizeof(req->cookie), &sc);
-	if (sc == NULL)
-		return -1;
-
-	ret = retrieve_cookie(s, req->cookie, sizeof(req->cookie), sc);
 	if (ret < 0) {
 		ret = -1;
 		goto cleanup;
 	}
 
-	if (sc->expiration < now) {
+	if (sc.expiration < now) {
 		ret = -1;
 		goto cleanup;
 	}
 	
 	memcpy(proc->cookie, req->cookie, sizeof(proc->cookie));
-	memcpy(proc->username, sc->username, sizeof(proc->username));
+	memcpy(proc->username, sc.username, sizeof(proc->username));
-	memcpy(proc->groupname, sc->groupname, sizeof(proc->groupname));
+	memcpy(proc->groupname, sc.groupname, sizeof(proc->groupname));
-	memcpy(proc->hostname, sc->hostname, sizeof(proc->hostname));
+	memcpy(proc->hostname, sc.hostname, sizeof(proc->hostname));
-	memcpy(proc->session_id, sc->session_id, sizeof(proc->session_id));
+	memcpy(proc->session_id, sc.session_id, sizeof(proc->session_id));
 	proc->session_id_size = sizeof(proc->session_id);
-	
+
 	proc->username[sizeof(proc->username)-1] = 0;
 	proc->groupname[sizeof(proc->groupname)-1] = 0;
 	proc->hostname[sizeof(proc->hostname)-1] = 0;
@@ -197,52 +193,33 @@ time_t now = time(0);
 		}
 	}
 	
-	/* ok auth ok. Renew the cookie. */
-	sc->expiration = time(0) + s->config->cookie_validity;
-	ret = store_cookie(s, sc);
-	if (ret < 0)
-		goto cleanup;
-
-	/* sc is freed in store_cookie() */
-	
 	return 0;
 cleanup:
-	free(sc);
 	return ret;
 }
 
 int generate_and_store_vals(main_server_st *s, struct proc_st* proc)
 {
 int ret;
-struct stored_cookie_st *sc;
+struct stored_cookie_st sc;
 
-	ret = gnutls_rnd(GNUTLS_RND_RANDOM, proc->cookie, sizeof(proc->cookie));
+        ret = gnutls_rnd(GNUTLS_RND_NONCE, proc->session_id, sizeof(proc->session_id));
-	if (ret < 0)
+        if (ret < 0)
-		return -2;
+                return -1;
-	ret = gnutls_rnd(GNUTLS_RND_NONCE, proc->session_id, sizeof(proc->session_id));
+        
-	if (ret < 0)
+        proc->session_id_size = sizeof(proc->session_id);
-		return -2;
-	proc->session_id_size = sizeof(proc->session_id);
-	
-	sc = calloc(1, sizeof(*sc));
-	if (sc == NULL)
-		return -2;
 
-	sc->expiration = time(0) + s->config->cookie_validity;
+	memcpy(sc.username, proc->username, sizeof(proc->username));
+	memcpy(sc.groupname, proc->groupname, sizeof(proc->groupname));
+	memcpy(sc.hostname, proc->hostname, sizeof(proc->hostname));
+	memcpy(sc.session_id, proc->session_id, sizeof(proc->session_id));
 	
-	memcpy(sc->cookie, proc->cookie, sizeof(proc->cookie));
+	sc.expiration = time(0) + s->config->cookie_validity;
-	memcpy(sc->username, proc->username, sizeof(sc->username));
-	memcpy(sc->groupname, proc->groupname, sizeof(sc->groupname));
-	memcpy(sc->hostname, proc->hostname, sizeof(sc->hostname));
-	memcpy(sc->session_id, proc->session_id, sizeof(sc->session_id));
 	
-	/* the sc pointer stays there */
+	ret = encrypt_cookie(s, proc->cookie, sizeof(proc->cookie), &sc);
-	ret = store_cookie(s, sc);
+	if (ret < 0)
-	if (ret < 0) {
-		free(sc);
 		return -1;
-	}
+
-	
 	return 0;
 }
 

src/main-misc.c

@@ -147,7 +147,7 @@ fail:
 	return ret;
 }
 
-static int accept_user(main_server_st *s, struct proc_st* proc, unsigned cmd)
+static int accept_user(main_server_st *s, struct proc_st* proc, unsigned cmd, const char* prev_user)
 {
 int ret;
 const char* group;
@@ -155,7 +155,7 @@ const char* group;
 	mslog(s, proc, LOG_DEBUG, "accepting user '%s'", proc->username);
 	proc_auth_deinit(s, proc);
 
-	ret = open_tun(s, &proc->lease);
+	ret = open_tun(s, &proc->lease, prev_user);
 	if (ret < 0) {
 		return -1;
 	}
@@ -201,6 +201,7 @@ int handle_commands(main_server_st *s, struct proc_st* proc)
 	struct iovec iov[2];
 	uint8_t cmd;
 	struct msghdr hdr;
+	/* FIXME: do not write directly to the union */
 	union {
 		struct cmd_auth_req_st auth;
 		struct cmd_auth_cookie_req_st cauth;
@@ -347,7 +348,7 @@ int handle_commands(main_server_st *s, struct proc_st* proc)
 				return ret;
 			}
 
-			ret = accept_user(s, proc, cmd);
+			ret = accept_user(s, proc, cmd, NULL);
 			if (ret < 0) {
 				goto cleanup;
 			}
@@ -355,6 +356,7 @@ int handle_commands(main_server_st *s, struct proc_st* proc)
 			goto cleanup;
 
 		case AUTH_COOKIE_REQ:
+			
 			if (cmd_data_len != sizeof(cmd_data.cauth)) {
 				mslog(s, proc, LOG_ERR, "error in received message (%u) length.", (unsigned)cmd);
 				return ERR_BAD_COMMAND;
@@ -366,7 +368,7 @@ int handle_commands(main_server_st *s, struct proc_st* proc)
 				return ret;
 			}
 
-			ret = accept_user(s, proc, cmd);
+			ret = accept_user(s, proc, cmd, (proc->username[0] != 0)?proc->username:NULL);
 			if (ret < 0) {
 				goto cleanup;
 			}

src/main.c

@@ -36,6 +36,7 @@
 #include <script-list.h>
 
 #include <gnutls/x509.h>
+#include <gnutls/crypto.h>
 #include <tlslib.h>
 #include "ipc.h"
 #include "setproctitle.h"
@@ -599,7 +600,6 @@ static void check_other_work(main_server_st *s)
 		need_maintainance = 0;
 		mslog(s, NULL, LOG_INFO, "Performing maintainance");
 		expire_tls_sessions(s);
-		expire_cookies(s);
 		expire_banned(s);
 		alarm(MAINTAINANCE_TIME(s));
 	}
@@ -655,6 +655,12 @@ int main(int argc, char** argv)
 
 	/* Initialize GnuTLS */
 	tls_global_init(&s);
+	
+	ret = gnutls_rnd(GNUTLS_RND_RANDOM, s.cookie_key, sizeof(s.cookie_key));
+	if (ret < 0) {
+		fprintf(stderr, "Error in cookie key generation\n");
+		exit(1);
+	}
 
 	/* load configuration */
 	ret = cmd_parser(argc, argv, &config);
@@ -675,12 +681,6 @@ int main(int argc, char** argv)
 
 	main_auth_init(&s);
 
-	ret = cookie_db_init(&s);
-	if (ret < 0) {
-		fprintf(stderr, "Could not initialize cookie database.\n");
-		exit(1);
-	}
-	
 	/* Listen to network ports */
 	ret = listen_ports(&config, &s.llist, config.name);
 	if (ret < 0) {
@@ -808,7 +808,6 @@ int main(int argc, char** argv)
 					 */
 					close(cmd_fd[0]);
 					clear_lists(&s);
-					erase_cookies(&s);
 
 					setproctitle(PACKAGE_NAME"-worker");
 					kill_on_parent_kill(SIGTERM);

src/main.h

@@ -8,6 +8,7 @@
 #include <vpn.h>
 #include <tlslib.h>
 #include "ipc.h"
+#include <cookies.h>
 
 int cmd_parser (int argc, char **argv, struct cfg_st* config);
 void reload_cfg_file(struct cfg_st* config);
@@ -70,7 +71,7 @@ struct proc_st {
 	char groupname[MAX_GROUPNAME_SIZE]; /* the owner's group */
 	char hostname[MAX_HOSTNAME_SIZE]; /* the requested hostname */
 	uint8_t cookie[COOKIE_SIZE]; /* the cookie associated with the session */
-	
+
 	void * auth_ctx; /* the context of authentication */
 	unsigned auth_status; /* PS_AUTH_ */
 };
@@ -99,7 +100,8 @@ typedef struct main_server_st {
 	struct cfg_st *config;
 	struct tun_st *tun;
 	hash_db_st *tls_db;
-	hash_db_st *cookie_db;
+	
+	uint8_t cookie_key[16];
 
 	/* tls credentials */
 	struct tls_st creds;
@@ -148,7 +150,7 @@ __attribute__ ((format(printf, 4, 5)))
 void  mslog_hex(const main_server_st * s, const struct proc_st* proc,
     	int priority, const char *prefix, uint8_t* bin, unsigned bin_size);
 
-int open_tun(main_server_st* s, struct lease_st** l);
+int open_tun(main_server_st* s, struct lease_st** l, const char* prev_name);
 int set_tun_mtu(main_server_st* s, struct proc_st * proc, unsigned mtu);
 
 int send_auth_reply_msg(main_server_st* s, struct proc_st* proc);

src/ocserv-args.c

@@ -2,7 +2,7 @@
  *
  *  DO NOT EDIT THIS FILE   (ocserv-args.c)
  *
- *  It has been AutoGen-ed  June 27, 2013 at 05:58:30 PM by AutoGen 5.17.3
+ *  It has been AutoGen-ed  July  1, 2013 at 12:18:22 PM by AutoGen 5.17.3
  *  From the definitions    ocserv-args.def
  *  and the template file   options
  *

src/ocserv-args.def

@@ -185,10 +185,6 @@ auth-timeout = 40
 # of that cookie.
 cookie-validity = 172800
 
-# A cookie database. If not set cookies are stored in memory and
-# server restarts won't preserve them.
-#cookie-db = /var/tmp/cookies.db
-
 # Script to call when a client connects and obtains an IP
 # Parameters are passed on the environment.
 # REASON, USERNAME, GROUPNAME, HOSTNAME (the hostname selected by client), 

src/ocserv-args.h

@@ -2,7 +2,7 @@
  *
  *  DO NOT EDIT THIS FILE   (ocserv-args.h)
  *
- *  It has been AutoGen-ed  June 27, 2013 at 05:58:30 PM by AutoGen 5.17.3
+ *  It has been AutoGen-ed  July  1, 2013 at 12:18:22 PM by AutoGen 5.17.3
  *  From the definitions    ocserv-args.def
  *  and the template file   options
  *

src/tun.c

@@ -289,7 +289,7 @@ static int set_network_info( main_server_st* s, const struct lease_st *lease)
 }
 
 
-int open_tun(main_server_st* s, struct lease_st** l)
+int open_tun(main_server_st* s, struct lease_st** l, const char* prev_name)
 {
 	int tunfd, ret, e;
 	struct ifreq ifr;
@@ -298,6 +298,7 @@ int open_tun(main_server_st* s, struct lease_st** l)
 	struct lease_st *last4, *tmp;
 	struct lease_st *last6;
 	unsigned current = s->tun->total;
+	time_t now = time(0);
 	
 	last4 = last6 = NULL;
 		
@@ -305,7 +306,7 @@ int open_tun(main_server_st* s, struct lease_st** l)
         list_for_each(&s->tun->head, tmp, list) {
 		/* if the device isn't in use by the server and the IPs
 		 *  are free. */
-		if (tmp->in_use == 0) {
+		if (tmp->in_use == 0 && (tmp->available_at < now || (prev_name != NULL && strcmp(prev_name, tmp->name) == 0))) {
                         if ((tmp->lip6_len != 0 && icmp_ping6(s, (void*)&tmp->lip6, (void*)&tmp->rip6) == 0) ||
                           (tmp->lip4_len != 0 && icmp_ping4(s, (void*)&tmp->lip4, (void*)&tmp->rip4) == 0)) {
         			lease = tmp;
@@ -434,6 +435,7 @@ int open_tun(main_server_st* s, struct lease_st** l)
 	}
 	
 	lease->in_use = 1;
+	lease->available_at = now + s->config->cookie_validity;
 	lease->fd = tunfd;
 	*l = lease;
 

src/tun.h

@@ -11,6 +11,7 @@ struct lease_st {
 	char name[IFNAMSIZ];
 	unsigned int tun_nr;
 	unsigned int in_use;
+	time_t available_at; /* when it will be available */
 
         struct sockaddr_storage rip4;
         socklen_t rip4_len;

src/vpn.h

@@ -113,9 +113,6 @@ struct cfg_st {
 	unsigned rate_limit_ms; /* if non zero force a connection every rate_limit milliseconds */
 	unsigned ping_leases; /* non zero if we need to ping prior to leasing */
 
-	/* if gdbm is there */
-	char* cookie_db_name;
-
 	char *connect_script;
 	char *disconnect_script;
 
@@ -144,7 +141,6 @@ struct main_server_st;
 #define TLS_MASTER_SIZE 48
 #define MAX_HOSTNAME_SIZE MAX_USERNAME_SIZE
 #define MAX_GROUPNAME_SIZE MAX_USERNAME_SIZE
-#define COOKIE_SIZE 32
 #define MAX_SESSION_DATA_SIZE (4*1024)
 
 const char *human_addr(const struct sockaddr *sa, socklen_t salen,