/* packet-pflog.c * Routines for pflog (OpenBSD Firewall Logging) packet disassembly * * $Id: packet-pflog.c,v 1.2 2002/01/30 23:08:26 guy Exp $ * * Copyright 2001 Mike Frantzen * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #ifdef HAVE_CONFIG_H # include "config.h" #endif #ifdef HAVE_SYS_TYPES_H # include #endif #include #include #include #include "etypes.h" #include #include "packet-ip.h" #include "packet-ipv6.h" #include "packet-pflog.h" #ifndef offsetof /* Can't trust stddef.h to be there for us */ # define offsetof(type, member) ((size_t)(&((type *)0)->member)) #endif static dissector_handle_t data_handle, ip_handle, ipv6_handle, pflog_handle; /* header fields */ static int proto_pflog = -1; static int hf_pflog_af = -1; static int hf_pflog_ifname = -1; static int hf_pflog_rnr = -1; static int hf_pflog_reason = -1; static int hf_pflog_action = -1; static int hf_pflog_dir = -1; static gint ett_pflog = -1; static char *pf_reasons[PFRES_MAX+2] = PFRES_NAMES; void capture_pflog(const u_char *pd, int offset, int len, packet_counts *ld) { struct pfloghdr pflogh; if (!BYTES_ARE_IN_FRAME(offset, len, (int)PFLOG_HDRLEN)) { ld->other++; return; } offset += PFLOG_HDRLEN; /* Copy out the pflog header to insure alignment */ memcpy(&pflogh, pd, sizeof(pflogh)); NTOHL(pflogh.af); if (pflogh.af == BSD_PF_INET) capture_ip(pd, offset, len, ld); #ifdef notyet else if (pflogh.af == BSD_PF_INET6) capture_ipv6(pd, offset, len, ld); #endif else ld->other++; } static void dissect_pflog(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { struct pfloghdr pflogh; tvbuff_t *next_tvb; proto_tree *pflog_tree; proto_item *ti, *tf; char *why; if (check_col(pinfo->cinfo, COL_PROTOCOL)) col_set_str(pinfo->cinfo, COL_PROTOCOL, "pflog"); /* Copy out the pflog header to insure alignment */ tvb_memcpy(tvb, (guint8 *)&pflogh, 0, sizeof(pflogh)); /* Byteswap the header now */ NTOHL(pflogh.af); NTOHS(pflogh.rnr); NTOHS(pflogh.reason); NTOHS(pflogh.action); NTOHS(pflogh.dir); why = (pflogh.reason < PFRES_MAX) ? pf_reasons[pflogh.reason] : "unkn"; if (tree) { ti = proto_tree_add_protocol_format(tree, proto_pflog, tvb, 0, PFLOG_HDRLEN, "PF Log %s %s on %s by rule %d", pflogh.af == BSD_PF_INET ? "IPv4" : pflogh.af == BSD_PF_INET6 ? "IPv6" : "unkn", pflogh.action == PF_PASS ? "passed" : pflogh.action == PF_DROP ? "dropped" : pflogh.action == PF_SCRUB ? "scrubbed" : "unkn", pflogh.ifname, pflogh.rnr); pflog_tree = proto_item_add_subtree(ti, ett_pflog); tf = proto_tree_add_uint_format(pflog_tree, hf_pflog_rnr, tvb, offsetof(struct pfloghdr, rnr), sizeof(pflogh.rnr), pflogh.rnr, "Rule Number: %d", pflogh.rnr); tf = proto_tree_add_string(pflog_tree, hf_pflog_ifname, tvb, offsetof(struct pfloghdr, reason), sizeof(pflogh.reason), pflogh.ifname); tf = proto_tree_add_string(pflog_tree, hf_pflog_reason, tvb, offsetof(struct pfloghdr, reason), sizeof(pflogh.reason), why); tf = proto_tree_add_string(pflog_tree, hf_pflog_action, tvb, offsetof(struct pfloghdr, action), sizeof(pflogh.action), pflogh.action == PF_PASS ? "pass" : pflogh.action == PF_DROP ? "drop" : pflogh.action == PF_SCRUB ? "scrub" : "unkn"); tf = proto_tree_add_string(pflog_tree, hf_pflog_dir, tvb, offsetof(struct pfloghdr, dir), sizeof(pflogh.dir), pflogh.dir == PF_IN ? "in" : "out"); } /* Set the tvbuff for the payload after the header */ next_tvb = tvb_new_subset(tvb, PFLOG_HDRLEN, -1, -1); pinfo->ethertype = (hf_pflog_af == BSD_PF_INET) ? ETHERTYPE_IP : ETHERTYPE_IPv6; if (pflogh.af == BSD_PF_INET) call_dissector(ip_handle, next_tvb, pinfo, tree); else if (pflogh.af == BSD_PF_INET6) call_dissector(ipv6_handle, next_tvb, pinfo, tree); else call_dissector(data_handle, next_tvb, pinfo, tree); if (check_col(pinfo->cinfo, COL_INFO)) { col_prepend_fstr(pinfo->cinfo, COL_INFO, "[%s %s/#%d] ", pflogh.action == PF_PASS ? "passed" : pflogh.action == PF_DROP ? "dropped" : pflogh.action == PF_SCRUB ? "scrubbed" : "unkn", pflogh.ifname, pflogh.rnr); } } void proto_register_pflog(void) { static hf_register_info hf[] = { { &hf_pflog_af, { "Address Family", "pflog.af", FT_UINT32, BASE_DEC, NULL, 0x0, "Protocol (IPv4 vs IPv6)", HFILL }}, { &hf_pflog_ifname, { "Interface", "pflog.ifname", FT_STRING, BASE_NONE, NULL, 0x0, "Interface", HFILL }}, { &hf_pflog_rnr, { "Rule Number", "pflog.rnr", FT_UINT16, BASE_DEC, NULL, 0x0, "Last matched firewall rule number", HFILL }}, { &hf_pflog_reason, { "Reason", "pflog.reason", FT_STRING, BASE_NONE, NULL, 0x0, "Reason for logging the packet", HFILL }}, { &hf_pflog_action, { "Action", "pflog.action", FT_STRING, BASE_NONE, NULL, 0x0, "Action taken by PF on the packet", HFILL }}, { &hf_pflog_dir, { "Direction", "pflog.dir", FT_STRING, BASE_NONE, NULL, 0x0, "Direction of packet in stack (inbound versus outbound)", HFILL }}, }; static gint *ett[] = { &ett_pflog }; proto_pflog = proto_register_protocol("pflog", "pflog", "pflog"); proto_register_field_array(proto_pflog, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); register_dissector("pflog", dissect_pflog, proto_pflog); } void proto_reg_handoff_pflog(void) { dissector_handle_t pflog_handle; pflog_handle = find_dissector("pflog"); ip_handle = find_dissector("ip"); ipv6_handle = find_dissector("ipv6"); data_handle = find_dissector("data"); dissector_add("wtap_encap", WTAP_ENCAP_PFLOG, pflog_handle); }