diff options
Diffstat (limited to 'bgpd/bgp_open.c')
| -rw-r--r-- | bgpd/bgp_open.c | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/bgpd/bgp_open.c b/bgpd/bgp_open.c index cd235770..38431d4c 100644 --- a/bgpd/bgp_open.c +++ b/bgpd/bgp_open.c @@ -34,6 +34,7 @@ Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA #include "bgpd/bgp_fsm.h" #include "bgpd/bgp_packet.h" #include "bgpd/bgp_open.h" +#include "bgpd/bgp_aspath.h" #include "bgpd/bgp_vty.h" /* BGP-4 Multiprotocol Extentions lead us to the complex world. We can @@ -427,6 +428,19 @@ bgp_capability_restart (struct peer *peer, struct capability_header *caphdr) return 0; } +static as_t +bgp_capability_as4 (struct peer *peer, struct capability_header *hdr) +{ + as_t as4 = stream_getl (BGP_INPUT(peer)); + + if (BGP_DEBUG (as4, AS4)) + zlog_debug ("%s [AS4] about to set cap PEER_CAP_AS4_RCV, got as4 %u", + peer->host, as4); + SET_FLAG (peer->cap, PEER_CAP_AS4_RCV); + + return as4; +} + static struct message capcode_str[] = { { 0, ""}, @@ -507,6 +521,7 @@ bgp_capability_parse (struct peer *peer, size_t length, u_char **error) case CAPABILITY_CODE_ORF: case CAPABILITY_CODE_ORF_OLD: case CAPABILITY_CODE_RESTART: + case CAPABILITY_CODE_AS4: case CAPABILITY_CODE_DYNAMIC: /* Check length. */ if (caphdr.length < cap_minsizes[caphdr.code]) @@ -566,6 +581,14 @@ bgp_capability_parse (struct peer *peer, size_t length, u_char **error) case CAPABILITY_CODE_DYNAMIC: SET_FLAG (peer->cap, PEER_CAP_DYNAMIC_RCV); break; + case CAPABILITY_CODE_AS4: + /* Already handled as a special-case parsing of the capabilities + * at the beginning of OPEN processing. So we care not a jot + * for the value really, only error case. + */ + if (!bgp_capability_as4 (peer, &caphdr)) + return -1; + break; default: if (caphdr.code > 128) { @@ -615,6 +638,86 @@ strict_capability_same (struct peer *peer) return 1; } +/* peek into option, stores ASN to *as4 if the AS4 capability was found. + * Returns 0 if no as4 found, as4cap value otherwise. + */ +as_t +peek_for_as4_capability (struct peer *peer, u_char length) +{ + struct stream *s = BGP_INPUT (peer); + size_t orig_getp = stream_get_getp (s); + size_t end = orig_getp + length; + as_t as4 = 0; + + /* The full capability parser will better flag the error.. */ + if (STREAM_READABLE(s) < length) + return 0; + + if (BGP_DEBUG (as4, AS4)) + zlog_info ("%s [AS4] rcv OPEN w/ OPTION parameter len: %u," + " peeking for as4", + peer->host, length); + /* the error cases we DONT handle, we ONLY try to read as4 out of + * correctly formatted options. + */ + while (stream_get_getp(s) < end) + { + u_char opt_type; + u_char opt_length; + + /* Check the length. */ + if (stream_get_getp (s) + 2 > end) + goto end; + + /* Fetch option type and length. */ + opt_type = stream_getc (s); + opt_length = stream_getc (s); + + /* Option length check. */ + if (stream_get_getp (s) + opt_length > end) + goto end; + + if (opt_type == BGP_OPEN_OPT_CAP) + { + unsigned long capd_start = stream_get_getp (s); + unsigned long capd_end = capd_start + opt_length; + + assert (capd_end <= end); + + while (stream_get_getp (s) < capd_end) + { + struct capability_header hdr; + + if (stream_get_getp (s) + 2 > capd_end) + goto end; + + hdr.code = stream_getc (s); + hdr.length = stream_getc (s); + + if ((stream_get_getp(s) + hdr.length) > capd_end) + goto end; + + if (hdr.code == CAPABILITY_CODE_AS4) + { + if (hdr.length != CAPABILITY_CODE_AS4_LEN) + goto end; + + if (BGP_DEBUG (as4, AS4)) + zlog_info ("[AS4] found AS4 capability, about to parse"); + as4 = bgp_capability_as4 (peer, &hdr); + + goto end; + } + stream_forward_getp (s, hdr.length); + } + } + } + +end: + stream_set_getp (s, orig_getp); + return as4; +} + /* Parse open option */ int bgp_open_option_parse (struct peer *peer, u_char length, int *capability) @@ -815,6 +918,7 @@ bgp_open_capability (struct stream *s, struct peer *peer) unsigned long cp; afi_t afi; safi_t safi; + as_t local_as; /* Remember current pointer for Opt Parm Len. */ cp = stream_get_endp (s); @@ -901,6 +1005,18 @@ bgp_open_capability (struct stream *s, struct peer *peer) stream_putc (s, CAPABILITY_CODE_REFRESH); stream_putc (s, CAPABILITY_CODE_REFRESH_LEN); + /* AS4 */ + SET_FLAG (peer->cap, PEER_CAP_AS4_ADV); + stream_putc (s, BGP_OPEN_OPT_CAP); + stream_putc (s, CAPABILITY_CODE_AS4_LEN + 2); + stream_putc (s, CAPABILITY_CODE_AS4); + stream_putc (s, CAPABILITY_CODE_AS4_LEN); + if ( peer->change_local_as ) + local_as = peer->change_local_as; + else + local_as = peer->local_as; + stream_putl (s, local_as ); + /* ORF capability. */ for (afi = AFI_IP ; afi < AFI_MAX ; afi++) for (safi = SAFI_UNICAST ; safi < SAFI_MAX ; safi++) |