From ad6fc87d64de30cdcdca18168a117d2ec24591da Mon Sep 17 00:00:00 2001 From: Michael Mann Date: Sun, 10 Jul 2016 23:47:28 -0400 Subject: Add proto_tree_add_checksum. This is an attempt to standardize display/handling of checksum fields for all dissectors. The main target is for dissectors that do validation, but dissectors that just report the checksum were also included just to make them easier to find in the future. Bug: 10620 Bug: 12058 Ping-Bug: 8859 Change-Id: Ia8abd86e42eaf8ed50de6b173409e914b17993bf Reviewed-on: https://code.wireshark.org/review/16380 Petri-Dish: Michael Mann Tested-by: Petri Dish Buildbot Reviewed-by: Jeff Morriss Reviewed-by: Michael Mann --- epan/dissectors/packet-icmpv6.c | 75 +++++++++++++++++------------------------ 1 file changed, 30 insertions(+), 45 deletions(-) (limited to 'epan/dissectors/packet-icmpv6.c') diff --git a/epan/dissectors/packet-icmpv6.c b/epan/dissectors/packet-icmpv6.c index 642b7edf39..3d830c7248 100644 --- a/epan/dissectors/packet-icmpv6.c +++ b/epan/dissectors/packet-icmpv6.c @@ -97,7 +97,7 @@ static int proto_icmpv6 = -1; static int hf_icmpv6_type = -1; static int hf_icmpv6_code = -1; static int hf_icmpv6_checksum = -1; -static int hf_icmpv6_checksum_bad = -1; +static int hf_icmpv6_checksum_status = -1; static int hf_icmpv6_reserved = -1; static int hf_icmpv6_data = -1; static int hf_icmpv6_unknown_data = -1; @@ -3470,12 +3470,12 @@ static int dissect_icmpv6(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data) { proto_tree *icmp6_tree = NULL, *flag_tree = NULL; - proto_item *ti = NULL, *hidden_item, *checksum_item = NULL, *code_item = NULL, *ti_flag = NULL; + proto_item *ti = NULL, *checksum_item = NULL, *code_item = NULL, *ti_flag = NULL; const char *code_name = NULL; guint length = 0, reported_length; vec_t cksum_vec[4]; guint32 phdr[2]; - guint16 cksum, computed_cksum; + guint16 cksum; int offset; tvbuff_t *next_tvb; guint8 icmp6_type, icmp6_code; @@ -3540,46 +3540,32 @@ dissect_icmpv6(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data) col_set_str(pinfo->cinfo, COL_INFO, "Direct IPv6 Connectivity Test"); } - if (tree) { - if (code_name) - proto_item_append_text(code_item, " (%s)", code_name); - checksum_item = proto_tree_add_item(icmp6_tree, hf_icmpv6_checksum, tvb, offset, 2, ENC_BIG_ENDIAN); - } + if (code_name) + proto_item_append_text(code_item, " (%s)", code_name); cksum = tvb_get_ntohs(tvb, offset); - - if (1) { /* There's an expert info in here so always execute */ - length = tvb_captured_length(tvb); - reported_length = tvb_reported_length(tvb); - if (!pinfo->fragmented && length >= reported_length && !pinfo->flags.in_error_pkt) { - /* The packet isn't part of a fragmented datagram, isn't truncated, - * and we aren't in an ICMP error packet, so we can checksum it. - */ - - /* Set up the fields of the pseudo-header. */ - SET_CKSUM_VEC_PTR(cksum_vec[0], (const guint8 *)pinfo->src.data, pinfo->src.len); - SET_CKSUM_VEC_PTR(cksum_vec[1], (const guint8 *)pinfo->dst.data, pinfo->dst.len); - phdr[0] = g_htonl(reported_length); - phdr[1] = g_htonl(IP_PROTO_ICMPV6); - SET_CKSUM_VEC_PTR(cksum_vec[2], (const guint8 *)&phdr, 8); - SET_CKSUM_VEC_TVB(cksum_vec[3], tvb, 0, reported_length); - computed_cksum = in_cksum(cksum_vec, 4); - - if (computed_cksum == 0) { - hidden_item = proto_tree_add_boolean(icmp6_tree, hf_icmpv6_checksum_bad, tvb, offset, 2, FALSE); - PROTO_ITEM_SET_HIDDEN(hidden_item); - proto_item_append_text(checksum_item, " [correct]"); - } else { - hidden_item = proto_tree_add_boolean(icmp6_tree, hf_icmpv6_checksum_bad, tvb, offset, 2, TRUE); - PROTO_ITEM_SET_HIDDEN(hidden_item); - proto_item_append_text(checksum_item, " [incorrect, should be 0x%04x]", in_cksum_shouldbe(cksum, computed_cksum)); - expert_add_info_format(pinfo, checksum_item, &ei_icmpv6_checksum, - "ICMPv6 Checksum Incorrect, should be 0x%04x", in_cksum_shouldbe(cksum, computed_cksum)); - } - } else { - proto_item_append_text(checksum_item, " [%s]", - pinfo->flags.in_error_pkt ? "in ICMP error packet" : "fragmented datagram"); - } + length = tvb_captured_length(tvb); + reported_length = tvb_reported_length(tvb); + if (!pinfo->fragmented && length >= reported_length && !pinfo->flags.in_error_pkt) { + /* The packet isn't part of a fragmented datagram, isn't truncated, + * and we aren't in an ICMP error packet, so we can checksum it. + */ + + /* Set up the fields of the pseudo-header. */ + SET_CKSUM_VEC_PTR(cksum_vec[0], (const guint8 *)pinfo->src.data, pinfo->src.len); + SET_CKSUM_VEC_PTR(cksum_vec[1], (const guint8 *)pinfo->dst.data, pinfo->dst.len); + phdr[0] = g_htonl(reported_length); + phdr[1] = g_htonl(IP_PROTO_ICMPV6); + SET_CKSUM_VEC_PTR(cksum_vec[2], (const guint8 *)&phdr, 8); + SET_CKSUM_VEC_TVB(cksum_vec[3], tvb, 0, reported_length); + + proto_tree_add_checksum(icmp6_tree, tvb, 2, hf_icmpv6_checksum, hf_icmpv6_checksum_status, &ei_icmpv6_checksum, pinfo, in_cksum(cksum_vec, 4), + ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY|PROTO_CHECKSUM_IN_CKSUM); + } else { + checksum_item = proto_tree_add_checksum(icmp6_tree, tvb, 2, hf_icmpv6_checksum, hf_icmpv6_checksum_status, &ei_icmpv6_checksum, pinfo, 0, + ENC_BIG_ENDIAN, PROTO_CHECKSUM_NO_FLAGS); + proto_item_append_text(checksum_item, " [%s]", + pinfo->flags.in_error_pkt ? "in ICMP error packet" : "fragmented datagram"); } offset += 2; @@ -3612,8 +3598,7 @@ dissect_icmpv6(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data) * Shouldn't the nonce be at least 8 then? Why not just use (-1), * as it could really be any length, couldn't it? */ - if (tree) - proto_tree_add_item(icmp6_tree, hf_icmpv6_nonce, tvb, offset, 4, ENC_NA); + proto_tree_add_item(icmp6_tree, hf_icmpv6_nonce, tvb, offset, 4, ENC_NA); offset += 4; } else { if (!pinfo->flags.in_error_pkt) { @@ -4158,8 +4143,8 @@ proto_register_icmpv6(void) { &hf_icmpv6_checksum, { "Checksum", "icmpv6.checksum", FT_UINT16, BASE_HEX, NULL, 0x0, "Used to detect data corruption in the ICMPv6 message and parts of the IPv6 header", HFILL }}, - { &hf_icmpv6_checksum_bad, - { "Bad Checksum", "icmpv6.checksum_bad", FT_BOOLEAN, BASE_NONE, NULL, 0x0, + { &hf_icmpv6_checksum_status, + { "Checksum Status", "icmpv6.checksum.status", FT_UINT8, BASE_NONE, VALS(proto_checksum_vals), 0x0, NULL, HFILL }}, { &hf_icmpv6_reserved, { "Reserved", "icmpv6.reserved", FT_BYTES, BASE_NONE, NULL, 0x0, -- cgit v1.2.3