Fix bugs in OSPF MD5 authentication. First bug is that default

values for MD5 password ID changed during reconfigure, Second
bug is that BIRD chooses password in first-fit manner, but RFC
says that it should use the one with the latest generate-from.

It also modifies the syntax for multiple passwords.
Now it is possible to just add more 'password' statements
to the interface section and it is not needed to use
'passwords' section. Old syntax can be used too.

doc/bird.sgml

@@ -1072,16 +1072,14 @@ protocol ospf <name> {
 			rx buffer [normal|large|<num>];
 			type [broadcast|nonbroadcast|pointopoint];
 			strict nonbroadcast <switch>;
-			authentication [none|simple];
+			authentication [none|simple|cryptographics];
 			password "<text>";
-			passwords {
-				password "<text>" {
-					id <num>;
-					generate from "<date>";
-					generate to "<date>";
-					accept from "<date>";
-					accept to "<date>";
-				};
+			password "<text>" {
+				id <num>;
+				generate from "<date>";
+				generate to "<date>";
+				accept from "<date>";
+				accept to "<date>";
 			};
 			neighbors {
 				<ip>;
@@ -1210,7 +1208,7 @@ protocol ospf <name> {
 	 very weak.
 
 	<tag>authentication cryptographic</tag>
-	 16-byte long md5 digest is appended to every packet. For the digest
+	 16-byte long MD5 digest is appended to every packet. For the digest
          generation 16-byte long passwords are used. Those passwords are 
          not sent via network, so this mechanismus is quite secure.
          Packets can still be read by an attacker.
@@ -1220,7 +1218,9 @@ protocol ospf &lt;name&gt; {
 
 	<tag>id <M>num</M></tag>
 	 ID of the password, (0-255). If it's not used, BIRD will choose
-	 some automatically.
+	 ID based on an order of the password item in the interface. For
+	 example, second password item in one interface will have default
+	 ID 2.  
 
 	<tag>generate from <M>date</M></tag>
 	 The start time of the usage of the password for packet signing.
@@ -1439,7 +1439,7 @@ RIP on networks where maximal distance is higher than 15 hosts. You can read mor
 URL="http://www.ietf.org/html.charters/rip-charter.html" name="http://www.ietf.org/html.charters/rip-charter.html">. Both IPv4  
 (RFC 1723<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc1723.txt">)
 and IPv6 (RFC 2080<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc2080.txt">) versions of RIP are supported by BIRD, historical RIPv1 (RFC 1058<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc1058.txt">)is
-not currently supported. RIPv4 md5 authentication (RFC 2082<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc2082.txt">) is supported.
+not currently supported. RIPv4 MD5 authentication (RFC 2082<htmlurl url="ftp://ftp.rfc-editor.org/in-notes/rfc2082.txt">) is supported.
 
 <p>RIP is a very simple protocol, and it has a lot of shortcomings. Slow
 convergence, big network load and inability to handle larger networks
@@ -1454,7 +1454,7 @@ because there are no good implementations of OSPFv3.
 <descrip>
 	<tag/authentication none|plaintext|md5/ selects authentication method to be used. <cf/none/ means that
 	  packets are not authenticated at all, <cf/plaintext/ means that a plaintext password is embedded
-	  into each packet, and <cf/md5/ means that packets are authenticated using a md5 cryptographic
+	  into each packet, and <cf/md5/ means that packets are authenticated using a MD5 cryptographic
 	  hash. If you set authentication to not-none, it is a good idea to add <cf>passwords { }</cf>
 	  section. Default: none.
 

nest/config.Y

@@ -20,6 +20,16 @@ static struct proto_config *this_proto;
 static struct iface_patt *this_ipatt;
 static list *this_p_list;
 static struct password_item *this_p_item;
+static int password_id;
+
+static list *
+get_passwords(void)
+{
+  list *rv = this_p_list;
+  this_p_list = NULL;
+  return rv;
+}
+
 
 CF_DECLS
 
@@ -37,7 +47,6 @@ CF_ENUM(T_ENUM_RTD, RTD_, ROUTER, DEVICE, BLACKHOLE, UNREACHABLE, PROHIBIT)
 %type <i32> idval
 %type <f> imexport
 %type <r> rtable
-%type <p> password_list password_begin password_begin_list
 %type <s> optsym
 %type <ra> r_args
 %type <i> echo_mask echo_size debug_mask debug_list debug_flag import_or_proto
@@ -197,6 +206,11 @@ debug_flag:
 
 /* Password lists */
 
+password_list:
+   PASSWORDS '{' password_items '}'
+ | password_item
+;
+
 password_items: 
     /* empty */
   | password_item ';' password_items
@@ -209,14 +223,18 @@ password_item:
 
 password_item_begin:
    PASSWORD TEXT {
-     static int id = 1;
+     if (!this_p_list) {
+     	this_p_list = cfg_alloc(sizeof(list));
+     	init_list(this_p_list);
+        password_id = 1;
+     }
      this_p_item = cfg_alloc(sizeof (struct password_item));
      this_p_item->password = $2;
      this_p_item->genfrom = 0;
      this_p_item->gento = TIME_INFINITY;
      this_p_item->accfrom = 0;
      this_p_item->accto = TIME_INFINITY;
-     this_p_item->id = id++;
+     this_p_item->id = password_id++;
      add_tail(this_p_list, &this_p_item->n);
    }
 ;
@@ -230,36 +248,6 @@ password_item_params:
  | ID expr ';' password_item_params { this_p_item->id = $2; if ($2 <= 0) cf_error("Password ID has to be greated than zero."); }
  ;
 
-password_list:
-   password_begin_list '{' password_items '}' {
-     $$ = $1;
-   }
- | password_begin
-;
-
-password_begin_list:
-  PASSWORDS {
-     this_p_list = cfg_alloc(sizeof(list));
-     init_list(this_p_list);
-     $$ = (void *) this_p_list;
-  }
-;
-
-password_begin:
-  PASSWORD TEXT {
-     this_p_list = cfg_alloc(sizeof(list));
-     init_list(this_p_list);
-     this_p_item = cfg_alloc(sizeof (struct password_item));
-     this_p_item->password = $2;
-     this_p_item->genfrom = 0;
-     this_p_item->gento = TIME_INFINITY;
-     this_p_item->accfrom = 0;
-     this_p_item->accto = TIME_INFINITY;
-     this_p_item->id = 1;
-     add_tail(this_p_list, &this_p_item->n);
-     $$ = (void *) this_p_list;
-  }
-;
 
 /* Core commands */
 CF_CLI_HELP(SHOW, ..., [[Show status information]])

nest/password.c

@@ -14,19 +14,26 @@
 struct password_item *last_password_item = NULL;
 
 struct password_item *
-password_find(list *l)
+password_find(list *l, int first_fit)
 {
   struct password_item *pi;
+  struct password_item *pf = NULL;
 
   if (l)
   {
     WALK_LIST(pi, *l)
     {
       if ((pi->genfrom < now_real) && (pi->gento > now_real))
-        return pi;
+      {
+	if (first_fit)
+	  return pi;
+
+	if (!pf || pf->genfrom < pi->genfrom)
+	  pf = pi;
+      }
     }
   }
-  return NULL;
+  return pf;
 }
 
 void password_cpy(char *dst, char *src, int size)

nest/password.h

@@ -22,7 +22,7 @@ struct password_item {
 
 extern struct password_item *last_password_item;
 
-struct password_item *password_find(list *);
+struct password_item *password_find(list *l, int first_fit);
 void password_cpy(char *dst, char *src, int size);
 
 #endif

proto/ospf/config.Y

@@ -32,7 +32,7 @@ CF_KEYWORDS(RX, BUFFER, LARGE, NORMAL)
 
 CF_GRAMMAR
 
-CF_ADDTO(proto, ospf_proto '}')
+CF_ADDTO(proto, ospf_proto '}' { OSPF_PATT->passwords = get_passwords(); } )
 
 ospf_proto_start: proto_start OSPF {
      this_proto = proto_config_new(&proto_ospf, sizeof(struct ospf_config));
@@ -102,7 +102,7 @@ ospf_vlink_item:
  | AUTHENTICATION NONE { OSPF_PATT->autype = OSPF_AUTH_NONE ; }
  | AUTHENTICATION SIMPLE { OSPF_PATT->autype = OSPF_AUTH_SIMPLE ; }
  | AUTHENTICATION CRYPTOGRAPHIC { OSPF_PATT->autype = OSPF_AUTH_CRYPT ; }
- | password_list {OSPF_PATT->passwords = (list *) $1; }
+ | password_list 
  ;
 
 ospf_vlink_start: VIRTUAL LINK idval
@@ -146,7 +146,7 @@ ospf_iface_item:
  | RX BUFFER LARGE { OSPF_PATT->rxbuf = OSPF_RXBUF_LARGE ; } 
  | RX BUFFER NORMAL { OSPF_PATT->rxbuf = OSPF_RXBUF_NORMAL ; } 
  | RX BUFFER expr { OSPF_PATT->rxbuf = $3 ; if ($3 < OSPF_RXBUF_MINSIZE) cf_error("Buffer size is too small") ; } 
- | password_list {OSPF_PATT->passwords = (list *) $1; }
+ | password_list
  ;
 
 pref_list:

proto/ospf/packet.c

@@ -41,7 +41,7 @@ ospf_pkt_maxsize(struct ospf_iface *ifa)
 void
 ospf_pkt_finalize(struct ospf_iface *ifa, struct ospf_packet *pkt)
 {
-  struct password_item *passwd = password_find (ifa->passwords);
+  struct password_item *passwd = NULL;
   void *tail;
   struct MD5Context ctxt;
   char password[OSPF_AUTH_CRYPT_SIZE];
@@ -52,6 +52,7 @@ ospf_pkt_finalize(struct ospf_iface *ifa, struct ospf_packet *pkt)
   {
     case OSPF_AUTH_SIMPLE:
       bzero(&pkt->u, sizeof(union ospf_auth));
+      passwd = password_find(ifa->passwords, 1);
       if (!passwd)
       {
         log( L_ERR "No suitable password found for authentication" );
@@ -65,6 +66,7 @@ ospf_pkt_finalize(struct ospf_iface *ifa, struct ospf_packet *pkt)
 				  sizeof(struct ospf_packet), NULL);
       break;
     case OSPF_AUTH_CRYPT:
+      passwd = password_find(ifa->passwords, 0);
       if (!passwd)
       {
         log( L_ERR "No suitable password found for authentication" );
@@ -123,7 +125,7 @@ ospf_pkt_checkauth(struct ospf_neighbor *n, struct ospf_iface *ifa, struct ospf_
       return 1;
       break;
     case OSPF_AUTH_SIMPLE:
-      pass = password_find (ifa->passwords);
+      pass = password_find(ifa->passwords, 1);
       if(!pass)
       {
         OSPF_TRACE(D_PACKETS, "OSPF_auth: no password found");

proto/rip/auth.c

@@ -39,7 +39,7 @@ rip_incoming_authentication( struct proto *p, struct rip_block_auth *block, stru
   switch (ntohs(block->authtype)) {	/* Authentication type */
   case AT_PLAINTEXT: 
     {
-      struct password_item *passwd = password_find(P_CF->passwords);
+      struct password_item *passwd = password_find(P_CF->passwords, 1);
       DBG( "Plaintext passwd" );
       if (!passwd) {
 	log( L_AUTH "No passwords set and password authentication came" );
@@ -115,7 +115,7 @@ rip_incoming_authentication( struct proto *p, struct rip_block_auth *block, stru
 int
 rip_outgoing_authentication( struct proto *p, struct rip_block_auth *block, struct rip_packet *packet, int num )
 {
-  struct password_item *passwd = password_find( P_CF->passwords);
+  struct password_item *passwd = password_find(P_CF->passwords, 1);
 
   if (!P_CF->authtype)
     return PACKETLEN(num);

proto/rip/config.Y

@@ -34,7 +34,7 @@ CF_KEYWORDS(RIP, INFINITY, METRIC, PORT, PERIOD, GARBAGE, TIMEOUT, PASSWORDS,
 
 CF_GRAMMAR
 
-CF_ADDTO(proto, rip_cfg '}')
+CF_ADDTO(proto, rip_cfg '}' { RIP_CFG->passwords = get_passwords(); } )
 
 rip_cfg_start: proto_start RIP {
      this_proto = proto_config_new(&proto_rip, sizeof(struct rip_proto_config));
@@ -51,7 +51,7 @@ rip_cfg:
  | rip_cfg GARBAGE TIME expr ';' { RIP_CFG->garbage_time = $4; }
  | rip_cfg TIMEOUT TIME expr ';' { RIP_CFG->timeout_time = $4; }
  | rip_cfg AUTHENTICATION rip_auth ';' {RIP_CFG->authtype = $3; }
- | rip_cfg password_list ';' {RIP_CFG->passwords = (list *)$2; }
+ | rip_cfg password_list ';'
  | rip_cfg HONOR ALWAYS ';'    { RIP_CFG->honor = HO_ALWAYS; }
  | rip_cfg HONOR NEIGHBOR ';'    { RIP_CFG->honor = HO_NEIGHBOR; }
  | rip_cfg HONOR NEVER ';'    { RIP_CFG->honor = HO_NEVER; }