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Diffstat (limited to 'print-sll.c')
-rw-r--r-- | print-sll.c | 535 |
1 files changed, 535 insertions, 0 deletions
diff --git a/print-sll.c b/print-sll.c new file mode 100644 index 0000000..eb8d620 --- /dev/null +++ b/print-sll.c @@ -0,0 +1,535 @@ +/* + * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that: (1) source code distributions + * retain the above copyright notice and this paragraph in its entirety, (2) + * distributions including binary code include the above copyright notice and + * this paragraph in its entirety in the documentation or other materials + * provided with the distribution, and (3) all advertising materials mentioning + * features or use of this software display the following acknowledgement: + * ``This product includes software developed by the University of California, + * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of + * the University nor the names of its contributors may be used to endorse + * or promote products derived from this software without specific prior + * written permission. + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. + */ + +/* \summary: Linux cooked sockets capture printer */ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#ifdef HAVE_NET_IF_H +/* + * Include diag-control.h before <net/if.h>, which too defines a macro + * named ND_UNREACHABLE. + */ +#include "diag-control.h" +#include <net/if.h> +#endif + +#include "netdissect-stdinc.h" + +#define ND_LONGJMP_FROM_TCHECK +#include "netdissect.h" +#include "addrtoname.h" +#include "ethertype.h" +#include "extract.h" + +/* + * For captures on Linux cooked sockets, we construct a fake header + * that includes: + * + * a 2-byte "packet type" which is one of: + * + * LINUX_SLL_HOST packet was sent to us + * LINUX_SLL_BROADCAST packet was broadcast + * LINUX_SLL_MULTICAST packet was multicast + * LINUX_SLL_OTHERHOST packet was sent to somebody else + * LINUX_SLL_OUTGOING packet was sent *by* us; + * + * a 2-byte Ethernet protocol field; + * + * a 2-byte link-layer type; + * + * a 2-byte link-layer address length; + * + * an 8-byte source link-layer address, whose actual length is + * specified by the previous value. + * + * All fields except for the link-layer address are in network byte order. + * + * DO NOT change the layout of this structure, or change any of the + * LINUX_SLL_ values below. If you must change the link-layer header + * for a "cooked" Linux capture, introduce a new DLT_ type (ask + * "tcpdump-workers@lists.tcpdump.org" for one, so that you don't give it + * a value that collides with a value already being used), and use the + * new header in captures of that type, so that programs that can + * handle DLT_LINUX_SLL captures will continue to handle them correctly + * without any change, and so that capture files with different headers + * can be told apart and programs that read them can dissect the + * packets in them. + * + * This structure, and the #defines below, must be the same in the + * libpcap and tcpdump versions of "sll.h". + */ + +/* + * A DLT_LINUX_SLL fake link-layer header. + */ +#define SLL_HDR_LEN 16 /* total header length */ +#define SLL_ADDRLEN 8 /* length of address field */ + +struct sll_header { + nd_uint16_t sll_pkttype; /* packet type */ + nd_uint16_t sll_hatype; /* link-layer address type */ + nd_uint16_t sll_halen; /* link-layer address length */ + nd_byte sll_addr[SLL_ADDRLEN]; /* link-layer address */ + nd_uint16_t sll_protocol; /* protocol */ +}; + +/* + * A DLT_LINUX_SLL2 fake link-layer header. + */ +#define SLL2_HDR_LEN 20 /* total header length */ + +struct sll2_header { + nd_uint16_t sll2_protocol; /* protocol */ + nd_uint16_t sll2_reserved_mbz; /* reserved - must be zero */ + nd_uint32_t sll2_if_index; /* 1-based interface index */ + nd_uint16_t sll2_hatype; /* link-layer address type */ + nd_uint8_t sll2_pkttype; /* packet type */ + nd_uint8_t sll2_halen; /* link-layer address length */ + nd_byte sll2_addr[SLL_ADDRLEN]; /* link-layer address */ +}; + +/* + * The LINUX_SLL_ values for "sll_pkttype"; these correspond to the + * PACKET_ values on Linux, but are defined here so that they're + * available even on systems other than Linux, and so that they + * don't change even if the PACKET_ values change. + */ +#define LINUX_SLL_HOST 0 +#define LINUX_SLL_BROADCAST 1 +#define LINUX_SLL_MULTICAST 2 +#define LINUX_SLL_OTHERHOST 3 +#define LINUX_SLL_OUTGOING 4 + +/* + * The LINUX_SLL_ values for "sll_protocol"; these correspond to the + * ETH_P_ values on Linux, but are defined here so that they're + * available even on systems other than Linux. We assume, for now, + * that the ETH_P_ values won't change in Linux; if they do, then: + * + * if we don't translate them in "pcap-linux.c", capture files + * won't necessarily be readable if captured on a system that + * defines ETH_P_ values that don't match these values; + * + * if we do translate them in "pcap-linux.c", that makes life + * unpleasant for the BPF code generator, as the values you test + * for in the kernel aren't the values that you test for when + * reading a capture file, so the fixup code run on BPF programs + * handed to the kernel ends up having to do more work. + * + * Add other values here as necessary, for handling packet types that + * might show up on non-Ethernet, non-802.x networks. (Not all the ones + * in the Linux "if_ether.h" will, I suspect, actually show up in + * captures.) + */ +#define LINUX_SLL_P_802_3 0x0001 /* Novell 802.3 frames without 802.2 LLC header */ +#define LINUX_SLL_P_802_2 0x0004 /* 802.2 frames (not D/I/X Ethernet) */ + +static const struct tok sll_pkttype_values[] = { + { LINUX_SLL_HOST, "In" }, + { LINUX_SLL_BROADCAST, "B" }, + { LINUX_SLL_MULTICAST, "M" }, + { LINUX_SLL_OTHERHOST, "P" }, + { LINUX_SLL_OUTGOING, "Out" }, + { 0, NULL} +}; + +static void +sll_print(netdissect_options *ndo, const struct sll_header *sllp, u_int length) +{ + u_short ether_type; + + ndo->ndo_protocol = "sll"; + ND_PRINT("%3s ", + tok2str(sll_pkttype_values,"?",GET_BE_U_2(sllp->sll_pkttype))); + + /* + * XXX - check the link-layer address type value? + * For now, we just assume 6 means Ethernet. + * XXX - print others as strings of hex? + */ + if (GET_BE_U_2(sllp->sll_halen) == MAC_ADDR_LEN) + ND_PRINT("%s ", GET_ETHERADDR_STRING(sllp->sll_addr)); + + if (!ndo->ndo_qflag) { + ether_type = GET_BE_U_2(sllp->sll_protocol); + + if (ether_type <= MAX_ETHERNET_LENGTH_VAL) { + /* + * Not an Ethernet type; what type is it? + */ + switch (ether_type) { + + case LINUX_SLL_P_802_3: + /* + * Ethernet_802.3 IPX frame. + */ + ND_PRINT("802.3"); + break; + + case LINUX_SLL_P_802_2: + /* + * 802.2. + */ + ND_PRINT("802.2"); + break; + + default: + /* + * What is it? + */ + ND_PRINT("ethertype Unknown (0x%04x)", + ether_type); + break; + } + } else { + ND_PRINT("ethertype %s (0x%04x)", + tok2str(ethertype_values, "Unknown", ether_type), + ether_type); + } + ND_PRINT(", length %u: ", length); + } +} + +/* + * This is the top level routine of the printer. 'p' points to the + * Linux "cooked capture" header of the packet, 'h->ts' is the timestamp, + * 'h->len' is the length of the packet off the wire, and 'h->caplen' + * is the number of bytes actually captured. + */ +void +sll_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p) +{ + u_int caplen = h->caplen; + u_int length = h->len; + const struct sll_header *sllp; + u_short hatype; + u_short ether_type; + int llc_hdrlen; + u_int hdrlen; + + ndo->ndo_protocol = "sll"; + ND_TCHECK_LEN(p, SLL_HDR_LEN); + + sllp = (const struct sll_header *)p; + + if (ndo->ndo_eflag) + sll_print(ndo, sllp, length); + + /* + * Go past the cooked-mode header. + */ + length -= SLL_HDR_LEN; + caplen -= SLL_HDR_LEN; + p += SLL_HDR_LEN; + hdrlen = SLL_HDR_LEN; + + hatype = GET_BE_U_2(sllp->sll_hatype); + switch (hatype) { + + case 803: + /* + * This is an packet with a radiotap header; + * just dissect the payload as such. + */ + ndo->ndo_ll_hdr_len += SLL_HDR_LEN; + ndo->ndo_ll_hdr_len += ieee802_11_radio_print(ndo, p, length, caplen); + return; + } + ether_type = GET_BE_U_2(sllp->sll_protocol); + +recurse: + /* + * Is it (gag) an 802.3 encapsulation, or some non-Ethernet + * packet type? + */ + if (ether_type <= MAX_ETHERNET_LENGTH_VAL) { + /* + * Yes - what type is it? + */ + switch (ether_type) { + + case LINUX_SLL_P_802_3: + /* + * Ethernet_802.3 IPX frame. + */ + ipx_print(ndo, p, length); + break; + + case LINUX_SLL_P_802_2: + /* + * 802.2. + * Try to print the LLC-layer header & higher layers. + */ + llc_hdrlen = llc_print(ndo, p, length, caplen, NULL, NULL); + if (llc_hdrlen < 0) + goto unknown; /* unknown LLC type */ + hdrlen += llc_hdrlen; + break; + + default: + /*FALLTHROUGH*/ + + unknown: + /* packet type not known, print raw packet */ + if (!ndo->ndo_suppress_default_print) + ND_DEFAULTPRINT(p, caplen); + break; + } + } else if (ether_type == ETHERTYPE_8021Q) { + /* + * Print VLAN information, and then go back and process + * the enclosed type field. + */ + if (caplen < 4) { + ndo->ndo_protocol = "vlan"; + nd_print_trunc(ndo); + ndo->ndo_ll_hdr_len += hdrlen + caplen; + return; + } + if (ndo->ndo_eflag) { + uint16_t tag = GET_BE_U_2(p); + + ND_PRINT("%s, ", ieee8021q_tci_string(tag)); + } + + ether_type = GET_BE_U_2(p + 2); + if (ether_type <= MAX_ETHERNET_LENGTH_VAL) + ether_type = LINUX_SLL_P_802_2; + if (!ndo->ndo_qflag) { + ND_PRINT("ethertype %s, ", + tok2str(ethertype_values, "Unknown", ether_type)); + } + p += 4; + length -= 4; + caplen -= 4; + hdrlen += 4; + goto recurse; + } else { + if (ethertype_print(ndo, ether_type, p, length, caplen, NULL, NULL) == 0) { + /* ether_type not known, print raw packet */ + if (!ndo->ndo_eflag) + sll_print(ndo, sllp, length + SLL_HDR_LEN); + if (!ndo->ndo_suppress_default_print) + ND_DEFAULTPRINT(p, caplen); + } + } + + ndo->ndo_ll_hdr_len += hdrlen; +} + +static void +sll2_print(netdissect_options *ndo, const struct sll2_header *sllp, u_int length) +{ + u_short ether_type; + + ndo->ndo_protocol = "sll2"; + ND_PRINT("ifindex %u ", GET_BE_U_4(sllp->sll2_if_index)); + + /* + * XXX - check the link-layer address type value? + * For now, we just assume 6 means Ethernet. + * XXX - print others as strings of hex? + */ + if (GET_U_1(sllp->sll2_halen) == MAC_ADDR_LEN) + ND_PRINT("%s ", GET_ETHERADDR_STRING(sllp->sll2_addr)); + + if (!ndo->ndo_qflag) { + ether_type = GET_BE_U_2(sllp->sll2_protocol); + + if (ether_type <= MAX_ETHERNET_LENGTH_VAL) { + /* + * Not an Ethernet type; what type is it? + */ + switch (ether_type) { + + case LINUX_SLL_P_802_3: + /* + * Ethernet_802.3 IPX frame. + */ + ND_PRINT("802.3"); + break; + + case LINUX_SLL_P_802_2: + /* + * 802.2. + */ + ND_PRINT("802.2"); + break; + + default: + /* + * What is it? + */ + ND_PRINT("ethertype Unknown (0x%04x)", + ether_type); + break; + } + } else { + ND_PRINT("ethertype %s (0x%04x)", + tok2str(ethertype_values, "Unknown", ether_type), + ether_type); + } + ND_PRINT(", length %u: ", length); + } +} + +/* + * This is the top level routine of the printer. 'p' points to the + * Linux "cooked capture" header of the packet, 'h->ts' is the timestamp, + * 'h->len' is the length of the packet off the wire, and 'h->caplen' + * is the number of bytes actually captured. + */ +void +sll2_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p) +{ + u_int caplen = h->caplen; + u_int length = h->len; + const struct sll2_header *sllp; + u_short hatype; + u_short ether_type; + int llc_hdrlen; + u_int hdrlen; +#ifdef HAVE_NET_IF_H + uint32_t if_index; + char ifname[IF_NAMESIZE]; +#endif + + ndo->ndo_protocol = "sll2"; + ND_TCHECK_LEN(p, SLL2_HDR_LEN); + + sllp = (const struct sll2_header *)p; +#ifdef HAVE_NET_IF_H + if_index = GET_BE_U_4(sllp->sll2_if_index); + if (!if_indextoname(if_index, ifname)) + strncpy(ifname, "?", 2); + ND_PRINT("%-5s ", ifname); +#endif + + ND_PRINT("%-3s ", + tok2str(sll_pkttype_values, "?", GET_U_1(sllp->sll2_pkttype))); + + if (ndo->ndo_eflag) + sll2_print(ndo, sllp, length); + + /* + * Go past the cooked-mode header. + */ + length -= SLL2_HDR_LEN; + caplen -= SLL2_HDR_LEN; + p += SLL2_HDR_LEN; + hdrlen = SLL2_HDR_LEN; + + hatype = GET_BE_U_2(sllp->sll2_hatype); + switch (hatype) { + + case 803: + /* + * This is an packet with a radiotap header; + * just dissect the payload as such. + */ + ndo->ndo_ll_hdr_len += SLL2_HDR_LEN; + ndo->ndo_ll_hdr_len += ieee802_11_radio_print(ndo, p, length, caplen); + return; + } + ether_type = GET_BE_U_2(sllp->sll2_protocol); + +recurse: + /* + * Is it (gag) an 802.3 encapsulation, or some non-Ethernet + * packet type? + */ + if (ether_type <= MAX_ETHERNET_LENGTH_VAL) { + /* + * Yes - what type is it? + */ + switch (ether_type) { + + case LINUX_SLL_P_802_3: + /* + * Ethernet_802.3 IPX frame. + */ + ipx_print(ndo, p, length); + break; + + case LINUX_SLL_P_802_2: + /* + * 802.2. + * Try to print the LLC-layer header & higher layers. + */ + llc_hdrlen = llc_print(ndo, p, length, caplen, NULL, NULL); + if (llc_hdrlen < 0) + goto unknown; /* unknown LLC type */ + hdrlen += llc_hdrlen; + break; + + default: + /*FALLTHROUGH*/ + + unknown: + /* packet type not known, print raw packet */ + if (!ndo->ndo_suppress_default_print) + ND_DEFAULTPRINT(p, caplen); + break; + } + } else if (ether_type == ETHERTYPE_8021Q) { + /* + * Print VLAN information, and then go back and process + * the enclosed type field. + */ + if (caplen < 4) { + ndo->ndo_protocol = "vlan"; + nd_print_trunc(ndo); + ndo->ndo_ll_hdr_len += hdrlen + caplen; + return; + } + if (ndo->ndo_eflag) { + uint16_t tag = GET_BE_U_2(p); + + ND_PRINT("%s, ", ieee8021q_tci_string(tag)); + } + + ether_type = GET_BE_U_2(p + 2); + if (ether_type <= MAX_ETHERNET_LENGTH_VAL) + ether_type = LINUX_SLL_P_802_2; + if (!ndo->ndo_qflag) { + ND_PRINT("ethertype %s, ", + tok2str(ethertype_values, "Unknown", ether_type)); + } + p += 4; + length -= 4; + caplen -= 4; + hdrlen += 4; + goto recurse; + } else { + if (ethertype_print(ndo, ether_type, p, length, caplen, NULL, NULL) == 0) { + /* ether_type not known, print raw packet */ + if (!ndo->ndo_eflag) + sll2_print(ndo, sllp, length + SLL2_HDR_LEN); + if (!ndo->ndo_suppress_default_print) + ND_DEFAULTPRINT(p, caplen); + } + } + + ndo->ndo_ll_hdr_len += hdrlen; +} |