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Enhance BGP Update 

First step ! Remove ugly double switch(bgpa_type)... (use proto_item_append_text)

svn path=/trunk/; revision=50917
This commit is contained in:
Alexis La Goutte 2013-07-26 16:26:21 +00:00
parent aa27f065a1
commit 54fc4025e6
1 changed files with 130 additions and 234 deletions
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364
epan/dissectors/packet-bgp.c
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@ -862,6 +862,8 @@ static int hf_bgp_encaps_tunnel_subtlv_type = -1;
static int hf_bgp_mdt_safi_rd = -1;
static int hf_bgp_mdt_safi_ipv4_addr = -1;
static int hf_bgp_mdt_safi_group_addr = -1;
static int hf_bgp_update_path_attribute = -1;
static int hf_bgp_flags_optional = -1;
static int hf_bgp_flags_transitive = -1;
static int hf_bgp_flags_partial = -1;
@ -3077,7 +3079,7 @@ dissect_bgp_update(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo)
i = 2;
while (i < len) {
proto_item *hidden_item;
const char *msg;
proto_item *ti_pa;
int off;
gint k;
guint16 alen, tlen, aoff, aoff_save;
@ -3099,18 +3101,67 @@ dissect_bgp_update(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo)
}
tlen = alen;
/* This is kind of ugly - similar code appears twice, but it
helps browsing attrs. */
/* the first switch prints things in the title of the subtree */
ti_pa = proto_tree_add_item(subtree, hf_bgp_update_path_attribute, tvb, o + i, tlen + aoff, ENC_NA);
proto_item_append_text(ti_pa, " - %s", val_to_str_const(bgpa_type, bgpattr_type, "Unknown %d"));
subtree2 = proto_item_add_subtree(ti_pa, ett_bgp_attr);
/* figure out flags */
ep_strbuf_truncate(junk_emstr, 0);
if (bgpa_flags & BGP_ATTR_FLAG_OPTIONAL) {
ep_strbuf_append(junk_emstr, "Optional, ");
}
else {
ep_strbuf_append(junk_emstr, "Well-known, ");
}
if (bgpa_flags & BGP_ATTR_FLAG_TRANSITIVE) {
ep_strbuf_append(junk_emstr, "Transitive, ");
}
else {
ep_strbuf_append(junk_emstr, "Non-transitive, ");
}
if (bgpa_flags & BGP_ATTR_FLAG_PARTIAL) {
ep_strbuf_append(junk_emstr, "Partial");
}
else {
ep_strbuf_append(junk_emstr, "Complete");
}
if (bgpa_flags & BGP_ATTR_FLAG_EXTENDED_LENGTH) {
ep_strbuf_append(junk_emstr, ", Extended Length");
}
ti = proto_tree_add_text(subtree2, tvb, o + i, 1,
"Flags: 0x%02x (%s)", bgpa_flags, junk_emstr->str);
subtree3 = proto_item_add_subtree(ti, ett_bgp_attr_flags);
/* add flag bitfield subtrees */
proto_tree_add_item(subtree3, hf_bgp_flags_optional, tvb, o + i, 1, ENC_BIG_ENDIAN);
proto_tree_add_item(subtree3, hf_bgp_flags_transitive, tvb, o + i, 1, ENC_BIG_ENDIAN);
proto_tree_add_item(subtree3, hf_bgp_flags_partial, tvb, o + i, 1, ENC_BIG_ENDIAN);
proto_tree_add_item(subtree3, hf_bgp_flags_extended_length, tvb, o + i, 1, ENC_BIG_ENDIAN);
proto_tree_add_text(subtree2, tvb,
o + i + 1, 1,
"Type code: %s (%u)",
val_to_str_const(bgpa_type, bgpattr_type, "Unknown"),
bgpa_type);
proto_tree_add_text(subtree2, tvb, o + i + BGP_SIZE_OF_PATH_ATTRIBUTE,
aoff - BGP_SIZE_OF_PATH_ATTRIBUTE, "Length: %d byte%s", tlen,
plurality(tlen, "", "s"));
/* Path Attribute Type */
switch (bgpa_type) {
case BGPTYPE_ORIGIN:
if (tlen != 1)
goto default_attribute_top;
msg = val_to_str_const(tvb_get_guint8(tvb, o + i + aoff), bgpattr_origin, "Unknown");
ti = proto_tree_add_text(subtree, tvb, o + i, tlen + aoff,
"%s: %s (%u byte%s)",
val_to_str_const(bgpa_type, bgpattr_type, "Unknown"),
msg, tlen + aoff, plurality(tlen + aoff, "", "s"));
if (tlen != 1) {
proto_tree_add_text(subtree2, tvb, o + i + aoff, tlen,
"Origin (invalid): %u byte%s", tlen,
plurality(tlen, "", "s"));
} else {
proto_tree_add_item(subtree2, hf_bgp_origin, tvb,
o + i + aoff, 1, ENC_BIG_ENDIAN);
proto_item_append_text(ti_pa, ": %s", val_to_str_const(tvb_get_guint8(tvb, o + i + aoff), bgpattr_origin, "Unknown"));
}
break;
case BGPTYPE_AS_PATH:
case BGPTYPE_NEW_AS_PATH:
@ -3213,229 +3264,8 @@ dissect_bgp_update(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo)
if (tlen == 0)
ep_strbuf_printf(as_path_emstr, "empty");
ti = proto_tree_add_text(subtree, tvb, o + i, tlen + aoff,
"%s: %s (%u byte%s)",
val_to_str_const(bgpa_type, bgpattr_type, "Unknown"),
as_path_emstr->str, tlen + aoff,
plurality(tlen + aoff, "", "s"));
break;
case BGPTYPE_NEXT_HOP:
if (tlen != 4)
goto default_attribute_top;
ipaddr = tvb_get_ipv4(tvb, o + i + aoff);
ti = proto_tree_add_text(subtree, tvb, o + i, tlen + aoff,
"%s: %s (%u byte%s)",
val_to_str_const(bgpa_type, bgpattr_type, "Unknown"),
ip_to_str((guint8 *)&ipaddr), tlen + aoff,
plurality(tlen + aoff, "", "s"));
break;
case BGPTYPE_MULTI_EXIT_DISC:
if (tlen != 4)
goto default_attribute_top;
ti = proto_tree_add_text(subtree, tvb, o + i, tlen + aoff,
"%s: %u (%u byte%s)",
val_to_str_const(bgpa_type, bgpattr_type, "Unknown"),
tvb_get_ntohl(tvb, o + i + aoff), tlen + aoff,
plurality(tlen + aoff, "", "s"));
break;
case BGPTYPE_LOCAL_PREF:
if (tlen != 4)
goto default_attribute_top;
ti = proto_tree_add_text(subtree, tvb, o + i, tlen + aoff,
"%s: %u (%u byte%s)",
val_to_str_const(bgpa_type, bgpattr_type, "Unknown"),
tvb_get_ntohl(tvb, o + i + aoff), tlen + aoff,
plurality(tlen + aoff, "", "s"));
break;
case BGPTYPE_ATOMIC_AGGREGATE:
if (tlen != 0)
goto default_attribute_top;
ti = proto_tree_add_text(subtree, tvb, o + i, tlen + aoff,
"%s (%u byte%s)",
val_to_str_const(bgpa_type, bgpattr_type, "Unknown"),
tlen + aoff, plurality(tlen + aoff, "", "s"));
break;
case BGPTYPE_AGGREGATOR:
if (tlen != 6 && tlen != 8)
goto default_attribute_top;
case BGPTYPE_NEW_AGGREGATOR:
if (bgpa_type == BGPTYPE_NEW_AGGREGATOR && tlen != 8)
goto default_attribute_top;
asn_len = tlen - 4;
ipaddr = tvb_get_ipv4(tvb, o + i + aoff + asn_len);
ti = proto_tree_add_text(subtree, tvb, o + i, tlen + aoff,
"%s: AS: %u origin: %s (%u byte%s)",
val_to_str_const(bgpa_type, bgpattr_type, "Unknown"),
(asn_len == 2) ? tvb_get_ntohs(tvb, o + i + aoff) :
tvb_get_ntohl(tvb, o + i + aoff),
ip_to_str((guint8 *)&ipaddr),
tlen + aoff, plurality(tlen + aoff, "", "s"));
break;
case BGPTYPE_COMMUNITIES:
if (tlen % 4 != 0)
goto default_attribute_top;
proto_item_append_text(ti_pa, ": %s", as_path_emstr->str);
/* (o + i + aoff) =
(o + current attribute + aoff bytes to first tuple) */
q = o + i + aoff;
end = q + tlen;
/* must be freed by second switch! */
/* "tlen * 12" (5 digits, a :, 5 digits + space ) should be
a good estimate of how long the communities string could
be */
if (communities_emstr == NULL)
communities_emstr = ep_strbuf_sized_new((tlen + 1) * 12, 0);
ep_strbuf_truncate(communities_emstr, 0);
/* snarf each community */
while (q < end) {
/* check for well-known communities */
if (tvb_get_ntohl(tvb, q) == BGP_COMM_NO_EXPORT)
ep_strbuf_append(communities_emstr, "NO_EXPORT ");
else if (tvb_get_ntohl(tvb, q) == BGP_COMM_NO_ADVERTISE)
ep_strbuf_append(communities_emstr, "NO_ADVERTISE ");
else if (tvb_get_ntohl(tvb, q) == BGP_COMM_NO_EXPORT_SUBCONFED)
ep_strbuf_append(communities_emstr, "NO_EXPORT_SUBCONFED ");
else {
ep_strbuf_append_printf(communities_emstr, "%u:%u ",
tvb_get_ntohs(tvb, q),
tvb_get_ntohs(tvb, q + 2));
}
q += 4;
}
/* cleanup end of string */
ep_strbuf_truncate(communities_emstr, communities_emstr->len - 1);
ti = proto_tree_add_text(subtree, tvb, o + i, tlen + aoff,
"%s: %s (%u byte%s)",
val_to_str_const(bgpa_type, bgpattr_type, "Unknown"),
communities_emstr->str, tlen + aoff,
plurality(tlen + aoff, "", "s"));
break;
case BGPTYPE_ORIGINATOR_ID:
if (tlen != 4)
goto default_attribute_top;
ipaddr = tvb_get_ipv4(tvb, o + i + aoff);
ti = proto_tree_add_text(subtree, tvb, o + i, tlen + aoff,
"%s: %s (%u byte%s)",
val_to_str_const(bgpa_type, bgpattr_type, "Unknown"),
ip_to_str((guint8 *)&ipaddr),
tlen + aoff, plurality(tlen + aoff, "", "s"));
break;
case BGPTYPE_CLUSTER_LIST:
if (tlen % 4 != 0)
goto default_attribute_top;
/* (o + i + aoff) =
(o + current attribute + aoff bytes to first tuple) */
q = o + i + aoff;
end = q + tlen;
/* must be freed by second switch! */
/* "tlen * 16" (12 digits, 3 dots + space ) should be
a good estimate of how long the cluster_list string could
be */
if (cluster_list_emstr == NULL)
cluster_list_emstr = ep_strbuf_sized_new((tlen + 1) * 16, 0);
ep_strbuf_truncate(cluster_list_emstr, 0);
/* snarf each cluster list */
while (q < end) {
ipaddr = tvb_get_ipv4(tvb, q);
ep_strbuf_append_printf(cluster_list_emstr, "%s ", ip_to_str((guint8 *)&ipaddr));
q += 4;
}
/* cleanup end of string */
ep_strbuf_truncate(cluster_list_emstr, cluster_list_emstr->len - 1);
ti = proto_tree_add_text(subtree, tvb, o + i, tlen + aoff,
"%s: %s (%u byte%s)",
val_to_str_const(bgpa_type, bgpattr_type, "Unknown"),
cluster_list_emstr->str, tlen + aoff,
plurality(tlen + aoff, "", "s"));
break;
case BGPTYPE_EXTENDED_COMMUNITY:
if (tlen %8 != 0)
break;
ti = proto_tree_add_text(subtree,tvb,o+i,tlen+aoff,
"%s: (%u byte%s)",
val_to_str_const(bgpa_type,bgpattr_type,"Unknown"),
tlen + aoff,
plurality(tlen + aoff, "", "s"));
break;
case BGPTYPE_SAFI_SPECIFIC_ATTR:
ti = proto_tree_add_text(subtree,tvb,o+i,tlen+aoff,
"%s: (%u byte%s)",
val_to_str_const(bgpa_type,bgpattr_type,"Unknown"),
tlen + aoff,
plurality(tlen + aoff, "", "s"));
break;
default:
default_attribute_top:
ti = proto_tree_add_text(subtree, tvb, o + i, tlen + aoff,
"%s (%u byte%s)",
val_to_str_const(bgpa_type, bgpattr_type, "Unknown"),
tlen + aoff, plurality(tlen + aoff, "", "s"));
} /* switch (bgpa.bgpa_type) */ /* end of first switch */
subtree2 = proto_item_add_subtree(ti, ett_bgp_attr);
/* figure out flags */
ep_strbuf_truncate(junk_emstr, 0);
if (bgpa_flags & BGP_ATTR_FLAG_OPTIONAL) {
ep_strbuf_append(junk_emstr, "Optional, ");
}
else {
ep_strbuf_append(junk_emstr, "Well-known, ");
}
if (bgpa_flags & BGP_ATTR_FLAG_TRANSITIVE) {
ep_strbuf_append(junk_emstr, "Transitive, ");
}
else {
ep_strbuf_append(junk_emstr, "Non-transitive, ");
}
if (bgpa_flags & BGP_ATTR_FLAG_PARTIAL) {
ep_strbuf_append(junk_emstr, "Partial");
}
else {
ep_strbuf_append(junk_emstr, "Complete");
}
if (bgpa_flags & BGP_ATTR_FLAG_EXTENDED_LENGTH) {
ep_strbuf_append(junk_emstr, ", Extended Length");
}
ti = proto_tree_add_text(subtree2, tvb, o + i, 1,
"Flags: 0x%02x (%s)", bgpa_flags, junk_emstr->str);
subtree3 = proto_item_add_subtree(ti, ett_bgp_attr_flags);
/* add flag bitfield subtrees */
proto_tree_add_item(subtree3, hf_bgp_flags_optional, tvb, o + i, 1, ENC_BIG_ENDIAN);
proto_tree_add_item(subtree3, hf_bgp_flags_transitive, tvb, o + i, 1, ENC_BIG_ENDIAN);
proto_tree_add_item(subtree3, hf_bgp_flags_partial, tvb, o + i, 1, ENC_BIG_ENDIAN);
proto_tree_add_item(subtree3, hf_bgp_flags_extended_length, tvb, o + i, 1, ENC_BIG_ENDIAN);
proto_tree_add_text(subtree2, tvb,
o + i + 1, 1,
"Type code: %s (%u)",
val_to_str_const(bgpa_type, bgpattr_type, "Unknown"),
bgpa_type);
proto_tree_add_text(subtree2, tvb, o + i + BGP_SIZE_OF_PATH_ATTRIBUTE,
aoff - BGP_SIZE_OF_PATH_ATTRIBUTE, "Length: %d byte%s", tlen,
plurality(tlen, "", "s"));
/* the second switch prints things in the actual subtree of each
attribute */
switch (bgpa_type) {
case BGPTYPE_ORIGIN:
if (tlen != 1) {
proto_tree_add_text(subtree2, tvb, o + i + aoff, tlen,
"Origin (invalid): %u byte%s", tlen,
plurality(tlen, "", "s"));
} else {
proto_tree_add_item(subtree2, hf_bgp_origin, tvb,
o + i + aoff, 1, ENC_BIG_ENDIAN);
}
break;
case BGPTYPE_AS_PATH:
case BGPTYPE_NEW_AS_PATH:
ti = proto_tree_add_text(subtree2, tvb, o + i + aoff, tlen,
"AS path: %s", as_path_emstr->str);
as_paths_tree = proto_item_add_subtree(ti, ett_bgp_as_paths);
@ -3527,7 +3357,8 @@ dissect_bgp_update(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo)
plurality(tlen, "", "s"));
} else {
proto_tree_add_item(subtree2, hf_bgp_next_hop, tvb,
o + i + aoff, tlen, ENC_BIG_ENDIAN);
o + i + aoff, 4, ENC_BIG_ENDIAN);
proto_item_append_text(ti_pa, ": %s ", tvb_ip_to_str(tvb, o + i + aoff));
}
break;
case BGPTYPE_MULTI_EXIT_DISC:
@ -3538,6 +3369,7 @@ dissect_bgp_update(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo)
} else {
proto_tree_add_item(subtree2, hf_bgp_multi_exit_disc, tvb,
o + i + aoff, tlen, ENC_BIG_ENDIAN);
proto_item_append_text(ti_pa,": %u", tvb_get_ntohl(tvb, o + i + aoff));
}
break;
case BGPTYPE_LOCAL_PREF:
@ -3548,6 +3380,7 @@ dissect_bgp_update(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo)
} else {
proto_tree_add_item(subtree2, hf_bgp_local_pref, tvb,
o + i + aoff, tlen, ENC_BIG_ENDIAN);
proto_item_append_text(ti_pa, ": %u", tvb_get_ntohl(tvb, o + i + aoff));
}
break;
case BGPTYPE_ATOMIC_AGGREGATE:
@ -3570,6 +3403,7 @@ dissect_bgp_update(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo)
"Aggregator (invalid): %u byte%s", tlen,
plurality(tlen, "", "s"));
else {
asn_len = tlen - 4;
aggregator_as = (asn_len == 2) ?
tvb_get_ntohs(tvb, o + i + aoff) :
@ -3578,6 +3412,9 @@ dissect_bgp_update(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo)
o + i + aoff, asn_len, aggregator_as);
proto_tree_add_item(subtree2, hf_bgp_aggregator_origin, tvb,
o + i + aoff + asn_len, 4, ENC_BIG_ENDIAN);
proto_item_append_text(ti_pa, ": AS: %u origin: %s", aggregator_as,
tvb_ip_to_str(tvb, o + i + aoff + asn_len));
}
break;
case BGPTYPE_COMMUNITIES:
@ -3588,6 +3425,39 @@ dissect_bgp_update(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo)
break;
}
/* (o + i + aoff) =
(o + current attribute + aoff bytes to first tuple) */
q = o + i + aoff;
end = q + tlen;
/* must be freed by second switch! */
/* "tlen * 12" (5 digits, a :, 5 digits + space ) should be
a good estimate of how long the communities string could
be */
if (communities_emstr == NULL)
communities_emstr = ep_strbuf_sized_new((tlen + 1) * 12, 0);
ep_strbuf_truncate(communities_emstr, 0);
/* snarf each community */
while (q < end) {
/* check for well-known communities */
if (tvb_get_ntohl(tvb, q) == BGP_COMM_NO_EXPORT)
ep_strbuf_append(communities_emstr, "NO_EXPORT ");
else if (tvb_get_ntohl(tvb, q) == BGP_COMM_NO_ADVERTISE)
ep_strbuf_append(communities_emstr, "NO_ADVERTISE ");
else if (tvb_get_ntohl(tvb, q) == BGP_COMM_NO_EXPORT_SUBCONFED)
ep_strbuf_append(communities_emstr, "NO_EXPORT_SUBCONFED ");
else {
ep_strbuf_append_printf(communities_emstr, "%u:%u ",
tvb_get_ntohs(tvb, q),
tvb_get_ntohs(tvb, q + 2));
}
q += 4;
}
/* cleanup end of string */
ep_strbuf_truncate(communities_emstr, communities_emstr->len - 1);
proto_item_append_text(ti_pa,": %s", communities_emstr->str);
ti = proto_tree_add_text(subtree2, tvb, o + i + aoff, tlen,
"Communities: %s", communities_emstr ? communities_emstr->str : "<none>");
communities_tree = proto_item_add_subtree(ti,
@ -3634,6 +3504,7 @@ dissect_bgp_update(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo)
} else {
proto_tree_add_item(subtree2, hf_bgp_originator_id, tvb,
o + i + aoff, tlen, ENC_BIG_ENDIAN);
proto_item_append_text(ti_pa, ": %s ", tvb_ip_to_str(tvb, o + i + aoff));
}
break;
case BGPTYPE_MP_REACH_NLRI:
@ -3788,6 +3659,28 @@ dissect_bgp_update(tvbuff_t *tvb, proto_tree *tree, packet_info *pinfo)
break;
}
/* (o + i + aoff) =
(o + current attribute + aoff bytes to first tuple) */
q = o + i + aoff;
end = q + tlen;
/* must be freed by second switch! */
/* "tlen * 16" (12 digits, 3 dots + space ) should be
a good estimate of how long the cluster_list string could
be */
if (cluster_list_emstr == NULL)
cluster_list_emstr = ep_strbuf_sized_new((tlen + 1) * 16, 0);
ep_strbuf_truncate(cluster_list_emstr, 0);
/* snarf each cluster list */
while (q < end) {
ep_strbuf_append_printf(cluster_list_emstr, "%s ", tvb_ip_to_str(tvb, q));
q += 4;
}
/* cleanup end of string */
ep_strbuf_truncate(cluster_list_emstr, cluster_list_emstr->len - 1);
proto_item_append_text(ti_pa, ": %s", cluster_list_emstr->str);
ti = proto_tree_add_text(subtree2, tvb, o + i + aoff, tlen,
"Cluster list: %s", cluster_list_emstr ? cluster_list_emstr->str : "<none>");
cluster_list_tree = proto_item_add_subtree(ti,
@ -5107,6 +5000,9 @@ proto_register_bgp(void)
{ &hf_bgp_mdt_safi_group_addr,
{ "Group Address", "bgp.mdt_safi_group_addr", FT_IPv4,
BASE_NONE, NULL, 0x0, NULL, HFILL}},
{ &hf_bgp_update_path_attribute,
{ "Path Attribut", "bgp.update.path_attribute", FT_NONE, BASE_NONE,
NULL, 0x0, NULL, HFILL}},
{ &hf_bgp_flags_optional,
{ "Optional", "bgp.flags.optional", FT_BOOLEAN, 8,
TFS(&tfs_optional_wellknown), BGP_ATTR_FLAG_OPTIONAL, NULL, HFILL}},