icmp: clean up the extension code and comments.

[tcpdump] / print-bgp.c

diff --git a/print-bgp.c b/print-bgp.c
index 6d24011ffff86457e3f58c9205443170692c4d29..ba927e4b26261dc7b010760e6647b1374900cff8 100644 (file)
--- a/print-bgp.c
+++ b/print-bgp.c
@@ -80,13 +80,15 @@ struct bgp_open {
     nd_uint16_t bgpo_holdtime;
     nd_uint32_t bgpo_id;
     nd_uint8_t  bgpo_optlen;
+    nd_uint8_t  bgpo_opttype;         /* RFC9072 */
+    nd_uint16_t bgpo_optlen_extended; /* RFC9072 */
     /* options should follow */
 };
 #define BGP_OPEN_SIZE        29    /* unaligned */
 
 struct bgp_opt {
-    nd_uint8_t bgpopt_type;
-    nd_uint8_t bgpopt_len;
+    nd_uint8_t  bgpopt_type;
+    nd_uint16_t bgpopt_len; /* Can be one or two bytes, depending on RFC9072 */
     /* variable length */
 };
 #define BGP_OPT_SIZE           2    /* some compilers may pad to 4 bytes */
@@ -271,12 +273,10 @@ static const struct tok bgp_notify_major_values[] = {
     { 0, NULL}
 };
 
-/* draft-ietf-idr-cease-subcode-02 */
+/* RFC 4486 */
 #define BGP_NOTIFY_MINOR_CEASE_MAXPRFX  1
-/* draft-ietf-idr-shutdown-07 */
 #define BGP_NOTIFY_MINOR_CEASE_SHUT     2
 #define BGP_NOTIFY_MINOR_CEASE_RESET    4
-#define BGP_NOTIFY_MINOR_CEASE_ADMIN_SHUTDOWN_LEN   128
 static const struct tok bgp_notify_minor_cease_values[] = {
     { BGP_NOTIFY_MINOR_CEASE_MAXPRFX, "Maximum Number of Prefixes Reached"},
     { BGP_NOTIFY_MINOR_CEASE_SHUT,    "Administrative Shutdown"},
@@ -461,6 +461,9 @@ static const struct tok bgp_safi_values[] = {
 #define BGP_EXT_COM_EIGRP_EXT_REMAS_REMID        0x8804
 #define BGP_EXT_COM_EIGRP_EXT_REMPROTO_REMMETRIC 0x8805
 
+/* Optional Parameters */
+#define BGP_OPEN_NON_EXT_OPT_TYPE_EXTENDED_LENGTH 255 /* Non-Ext OP Type */
+
 static const struct tok bgp_extd_comm_flag_values[] = {
     { 0x8000,                  "vendor-specific"},
     { 0x4000,                  "non-transitive"},
@@ -2387,7 +2390,6 @@ bgp_attr_print(netdissect_options *ndo,
             /*
              * Check if we can read the TLV data.
              */
-            ND_TCHECK_LEN(tptr + 3, length);
             if (tlen < length)
                 goto trunc;
 
@@ -2662,9 +2664,13 @@ bgp_open_print(netdissect_options *ndo,
     char astostr[AS_STR_SIZE];
     const struct bgp_open *bgp_open_header;
     u_int optslen;
+    uint8_t opsttype;
     const struct bgp_opt *bgpopt;
     const u_char *opt;
     u_int i;
+    uint8_t extended_opt_params = 0;
+    u_int open_size = BGP_OPEN_SIZE;
+    u_int opt_size = BGP_OPT_SIZE;
 
     ND_TCHECK_LEN(dat, BGP_OPEN_SIZE);
     if (length < BGP_OPEN_SIZE)
@@ -2680,22 +2686,32 @@ bgp_open_print(netdissect_options *ndo,
         GET_BE_U_2(bgp_open_header->bgpo_holdtime));
     ND_PRINT("ID %s", GET_IPADDR_STRING(bgp_open_header->bgpo_id));
     optslen = GET_U_1(bgp_open_header->bgpo_optlen);
-    ND_PRINT("\n\t  Optional parameters, length: %u", optslen);
+    opsttype = GET_U_1(bgp_open_header->bgpo_opttype);
+    if (opsttype == BGP_OPEN_NON_EXT_OPT_TYPE_EXTENDED_LENGTH) {
+        optslen = GET_BE_U_2(bgp_open_header->bgpo_optlen_extended);
+        extended_opt_params = 1;
+        open_size += 3;
+        opt_size += 1;
+    }
+    ND_PRINT("\n\t  Optional parameters%s, length: %u",
+             extended_opt_params ? " (Extended)" : "", optslen);
 
-    opt = dat + BGP_OPEN_SIZE;
-    length -= BGP_OPEN_SIZE;
+    opt = dat + open_size;
+    length -= open_size;
 
     i = 0;
     while (i < optslen) {
-        uint8_t opt_type, opt_len;
+        uint8_t opt_type;
+        uint16_t opt_len;
 
-        ND_TCHECK_LEN(opt + i, BGP_OPT_SIZE);
-        if (length < BGP_OPT_SIZE + i)
+        ND_TCHECK_LEN(opt + i, opt_size);
+        if (length < opt_size + i)
             goto trunc;
         bgpopt = (const struct bgp_opt *)(opt + i);
         opt_type = GET_U_1(bgpopt->bgpopt_type);
-        opt_len = GET_U_1(bgpopt->bgpopt_len);
-        if (BGP_OPT_SIZE + i + opt_len > optslen) {
+        opt_len = extended_opt_params ? GET_BE_U_2(bgpopt->bgpopt_len)
+                                      : GET_U_1(bgpopt->bgpopt_len);
+        if (opt_size + i + opt_len > optslen) {
             ND_PRINT("\n\t     Option %u, length: %u, goes past the end of the options",
                       opt_type, opt_len);
             break;
@@ -2710,7 +2726,7 @@ bgp_open_print(netdissect_options *ndo,
         switch(opt_type) {
 
         case BGP_OPT_CAP:
-            bgp_capabilities_print(ndo, opt + BGP_OPT_SIZE + i,
+            bgp_capabilities_print(ndo, opt + opt_size + i,
                                    opt_len);
             break;
 
@@ -2720,7 +2736,7 @@ bgp_open_print(netdissect_options *ndo,
                opt_type);
                break;
         }
-        i += BGP_OPT_SIZE + opt_len;
+        i += opt_size + opt_len;
     }
     return;
 trunc:
@@ -2922,8 +2938,6 @@ bgp_notification_print(netdissect_options *ndo,
     const struct bgp_notification *bgp_notification_header;
     const u_char *tptr;
     uint8_t bgpn_major, bgpn_minor;
-    uint8_t shutdown_comm_length;
-    uint8_t remainder_offset;
 
     ND_TCHECK_LEN(dat, BGP_NOTIFICATION_SIZE);
     if (length<BGP_NOTIFICATION_SIZE)
@@ -2976,7 +2990,7 @@ bgp_notification_print(netdissect_options *ndo,
                           bgpn_minor),
                   bgpn_minor);
 
-        /* draft-ietf-idr-cease-subcode-02 mentions optionally 7 bytes
+        /* RFC 4486 mentions optionally 7 bytes
          * for the maxprefix subtype, which may contain AFI, SAFI and MAXPREFIXES
          */
         if(bgpn_minor == BGP_NOTIFY_MINOR_CEASE_MAXPRFX && length >= BGP_NOTIFICATION_SIZE + 7) {
@@ -2989,18 +3003,17 @@ bgp_notification_print(netdissect_options *ndo,
                       GET_BE_U_4(tptr + 3));
         }
         /*
-         * draft-ietf-idr-shutdown describes a method to send a communication
+         * RFC 9003 describes a method to send a communication
          * intended for human consumption regarding the Administrative Shutdown
          */
         if ((bgpn_minor == BGP_NOTIFY_MINOR_CEASE_SHUT ||
              bgpn_minor == BGP_NOTIFY_MINOR_CEASE_RESET) &&
              length >= BGP_NOTIFICATION_SIZE + 1) {
             tptr = dat + BGP_NOTIFICATION_SIZE;
-            shutdown_comm_length = GET_U_1(tptr);
-            remainder_offset = 0;
+            uint8_t shutdown_comm_length = GET_U_1(tptr);
+            uint8_t remainder_offset = 0;
             /* garbage, hexdump it all */
-            if (shutdown_comm_length > BGP_NOTIFY_MINOR_CEASE_ADMIN_SHUTDOWN_LEN ||
-                shutdown_comm_length > length - (BGP_NOTIFICATION_SIZE + 1)) {
+            if (shutdown_comm_length > length - (BGP_NOTIFICATION_SIZE + 1)) {
                 ND_PRINT(", invalid Shutdown Communication length");
             }
             else if (shutdown_comm_length == 0) {
@@ -3009,7 +3022,6 @@ bgp_notification_print(netdissect_options *ndo,
             }
             /* a proper shutdown communication */
             else {
-                ND_TCHECK_LEN(tptr + 1, shutdown_comm_length);
                 ND_PRINT(", Shutdown Communication (length: %u): \"", shutdown_comm_length);
                 nd_printjn(ndo, tptr+1, shutdown_comm_length);
                 ND_PRINT("\"");