diff options
Diffstat (limited to 'contrib/tcpdump/print-llc.c')
| -rw-r--r-- | contrib/tcpdump/print-llc.c | 246 |
1 files changed, 160 insertions, 86 deletions
diff --git a/contrib/tcpdump/print-llc.c b/contrib/tcpdump/print-llc.c index 78b8631..6bdf599 100644 --- a/contrib/tcpdump/print-llc.c +++ b/contrib/tcpdump/print-llc.c @@ -20,20 +20,19 @@ * * Code by Matt Thomas, Digital Equipment Corporation * with an awful lot of hacking by Jeffrey Mogul, DECWRL - * - * $FreeBSD$ */ -#define NETDISSECT_REWORKED +/* \summary: IEEE 802.2 LLC printer */ + #ifdef HAVE_CONFIG_H #include "config.h" #endif -#include <tcpdump-stdinc.h> +#include <netdissect-stdinc.h> -#include "interface.h" +#include "netdissect.h" #include "addrtoname.h" -#include "extract.h" /* must come after interface.h */ +#include "extract.h" #include "llc.h" #include "ethertype.h" @@ -140,23 +139,31 @@ static const struct oui_tok oui_to_tok[] = { }; /* - * Returns non-zero IFF it succeeds in printing the header + * If we printed information about the payload, returns the length of the LLC + * header, plus the length of any SNAP header following it. + * + * Otherwise (for example, if the packet has unknown SAPs or has a SNAP + * header with an unknown OUI/PID combination), returns the *negative* + * of that value. */ int llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen, - const u_char *esrc, const u_char *edst, u_short *extracted_ethertype) + const struct lladdr_info *src, const struct lladdr_info *dst) { uint8_t dsap_field, dsap, ssap_field, ssap; uint16_t control; + int hdrlen; int is_u; - register int ret; - - *extracted_ethertype = 0; - if (caplen < 3 || length < 3) { + if (caplen < 3) { ND_PRINT((ndo, "[|llc]")); - ND_DEFAULTPRINT((u_char *)p, caplen); - return (1); + ND_DEFAULTPRINT((const u_char *)p, caplen); + return (caplen); + } + if (length < 3) { + ND_PRINT((ndo, "[|llc]")); + ND_DEFAULTPRINT((const u_char *)p, caplen); + return (length); } dsap_field = *p; @@ -174,15 +181,21 @@ llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen, * U frame. */ is_u = 1; + hdrlen = 3; /* DSAP, SSAP, 1-byte control field */ } else { /* * The control field in I and S frames is * 2 bytes... */ - if (caplen < 4 || length < 4) { + if (caplen < 4) { ND_PRINT((ndo, "[|llc]")); - ND_DEFAULTPRINT((u_char *)p, caplen); - return (1); + ND_DEFAULTPRINT((const u_char *)p, caplen); + return (caplen); + } + if (length < 4) { + ND_PRINT((ndo, "[|llc]")); + ND_DEFAULTPRINT((const u_char *)p, caplen); + return (length); } /* @@ -190,6 +203,7 @@ llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen, */ control = EXTRACT_LE_16BITS(p + 2); is_u = 0; + hdrlen = 4; /* DSAP, SSAP, 2-byte control field */ } if (ssap_field == LLCSAP_GLOBAL && dsap_field == LLCSAP_GLOBAL) { @@ -212,7 +226,7 @@ llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen, ND_PRINT((ndo, "IPX 802.3: ")); ipx_print(ndo, p, length); - return (1); + return (0); /* no LLC header */ } dsap = dsap_field & ~LLC_IG; @@ -234,21 +248,47 @@ llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen, } } + /* + * Skip LLC header. + */ + p += hdrlen; + length -= hdrlen; + caplen -= hdrlen; + + if (ssap == LLCSAP_SNAP && dsap == LLCSAP_SNAP + && control == LLC_UI) { + /* + * XXX - what *is* the right bridge pad value here? + * Does anybody ever bridge one form of LAN traffic + * over a networking type that uses 802.2 LLC? + */ + if (!snap_print(ndo, p, length, caplen, src, dst, 2)) { + /* + * Unknown packet type; tell our caller, by + * returning a negative value, so they + * can print the raw packet. + */ + return (-(hdrlen + 5)); /* include LLC and SNAP header */ + } else + return (hdrlen + 5); /* include LLC and SNAP header */ + } + if (ssap == LLCSAP_8021D && dsap == LLCSAP_8021D && control == LLC_UI) { - stp_print(ndo, p+3, length-3); - return (1); + stp_print(ndo, p, length); + return (hdrlen); } if (ssap == LLCSAP_IP && dsap == LLCSAP_IP && control == LLC_UI) { - if (caplen < 4 || length < 4) { - ND_PRINT((ndo, "[|llc]")); - ND_DEFAULTPRINT((u_char *)p, caplen); - return (1); - } - ip_print(ndo, p+4, length-4); - return (1); + /* + * This is an RFC 948-style IP packet, with + * an 802.3 header and an 802.2 LLC header + * with the source and destination SAPs being + * the IP SAP. + */ + ip_print(ndo, p, length); + return (hdrlen); } if (ssap == LLCSAP_IPX && dsap == LLCSAP_IPX && @@ -257,17 +297,15 @@ llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen, * This is an Ethernet_802.2 IPX frame, with an 802.3 * header and an 802.2 LLC header with the source and * destination SAPs being the IPX SAP. - * - * Skip DSAP, LSAP, and control field. */ if (ndo->ndo_eflag) ND_PRINT((ndo, "IPX 802.2: ")); - ipx_print(ndo, p+3, length-3); - return (1); + ipx_print(ndo, p, length); + return (hdrlen); } -#ifdef TCPDUMP_DO_SMB +#ifdef ENABLE_SMB if (ssap == LLCSAP_NETBEUI && dsap == LLCSAP_NETBEUI && (!(control & LLC_S_FMT) || control == LLC_U_FMT)) { /* @@ -280,58 +318,35 @@ llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen, * LLC_S_FMT, set in the first byte of the control field) * and UI frames (whose control field is just 3, LLC_U_FMT). */ - - /* - * Skip the LLC header. - */ - if (is_u) { - p += 3; - length -= 3; - } else { - p += 4; - length -= 4; - } netbeui_print(ndo, control, p, length); - return (1); + return (hdrlen); } #endif if (ssap == LLCSAP_ISONS && dsap == LLCSAP_ISONS && control == LLC_UI) { - isoclns_print(ndo, p + 3, length - 3, caplen - 3); - return (1); - } - - if (ssap == LLCSAP_SNAP && dsap == LLCSAP_SNAP - && control == LLC_UI) { - /* - * XXX - what *is* the right bridge pad value here? - * Does anybody ever bridge one form of LAN traffic - * over a networking type that uses 802.2 LLC? - */ - ret = snap_print(ndo, p+3, length-3, caplen-3, 2); - if (ret) - return (ret); + isoclns_print(ndo, p, length, caplen); + return (hdrlen); } if (!ndo->ndo_eflag) { if (ssap == dsap) { - if (esrc == NULL || edst == NULL) + if (src == NULL || dst == NULL) ND_PRINT((ndo, "%s ", tok2str(llc_values, "Unknown DSAP 0x%02x", dsap))); else ND_PRINT((ndo, "%s > %s %s ", - etheraddr_string(ndo, esrc), - etheraddr_string(ndo, edst), + (src->addr_string)(ndo, src->addr), + (dst->addr_string)(ndo, dst->addr), tok2str(llc_values, "Unknown DSAP 0x%02x", dsap))); } else { - if (esrc == NULL || edst == NULL) + if (src == NULL || dst == NULL) ND_PRINT((ndo, "%s > %s ", tok2str(llc_values, "Unknown SSAP 0x%02x", ssap), tok2str(llc_values, "Unknown DSAP 0x%02x", dsap))); else ND_PRINT((ndo, "%s %s > %s %s ", - etheraddr_string(ndo, esrc), + (src->addr_string)(ndo, src->addr), tok2str(llc_values, "Unknown SSAP 0x%02x", ssap), - etheraddr_string(ndo, edst), + (dst->addr_string)(ndo, dst->addr), tok2str(llc_values, "Unknown DSAP 0x%02x", dsap))); } } @@ -340,13 +355,31 @@ llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen, ND_PRINT((ndo, "Unnumbered, %s, Flags [%s], length %u", tok2str(llc_cmd_values, "%02x", LLC_U_CMD(control)), tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_U_POLL)), - length)); - - p += 3; + length + hdrlen)); if ((control & ~LLC_U_POLL) == LLC_XID) { + if (length == 0) { + /* + * XID with no payload. + * This could, for example, be an SNA + * "short form" XID. + */ + return (hdrlen); + } + if (caplen < 1) { + ND_PRINT((ndo, "[|llc]")); + if (caplen > 0) + ND_DEFAULTPRINT((const u_char *)p, caplen); + return (hdrlen); + } if (*p == LLC_XID_FI) { - ND_PRINT((ndo, ": %02x %02x", p[1], p[2])); + if (caplen < 3 || length < 3) { + ND_PRINT((ndo, "[|llc]")); + if (caplen > 0) + ND_DEFAULTPRINT((const u_char *)p, caplen); + } else + ND_PRINT((ndo, ": %02x %02x", p[1], p[2])); + return (hdrlen); } } } else { @@ -355,20 +388,38 @@ llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen, tok2str(llc_supervisory_values,"?",LLC_S_CMD(control)), LLC_IS_NR(control), tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_IS_POLL)), - length)); + length + hdrlen)); + return (hdrlen); /* no payload to print */ } else { ND_PRINT((ndo, "Information, send seq %u, rcv seq %u, Flags [%s], length %u", LLC_I_NS(control), LLC_IS_NR(control), tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_IS_POLL)), - length)); + length + hdrlen)); } } - return(1); + return (-hdrlen); +} + +static const struct tok * +oui_to_struct_tok(uint32_t orgcode) +{ + const struct tok *tok = null_values; + const struct oui_tok *otp; + + for (otp = &oui_to_tok[0]; otp->tok != NULL; otp++) { + if (otp->oui == orgcode) { + tok = otp->tok; + break; + } + } + return (tok); } int -snap_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen, u_int bridge_pad) +snap_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen, + const struct lladdr_info *src, const struct lladdr_info *dst, + u_int bridge_pad) { uint32_t orgcode; register u_short et; @@ -381,21 +432,17 @@ snap_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen, et = EXTRACT_16BITS(p + 3); if (ndo->ndo_eflag) { - const struct tok *tok = null_values; - const struct oui_tok *otp; - - for (otp = &oui_to_tok[0]; otp->tok != NULL; otp++) { - if (otp->oui == orgcode) { - tok = otp->tok; - break; - } - } - ND_PRINT((ndo, "oui %s (0x%06x), %s %s (0x%04x): ", + /* + * Somebody's already printed the MAC addresses, if there + * are any, so just print the SNAP header, not the MAC + * addresses. + */ + ND_PRINT((ndo, "oui %s (0x%06x), %s %s (0x%04x), length %u: ", tok2str(oui_values, "Unknown", orgcode), orgcode, (orgcode == 0x000000 ? "ethertype" : "pid"), - tok2str(tok, "Unknown", et), - et)); + tok2str(oui_to_struct_tok(orgcode), "Unknown", et), + et, length - 5)); } p += 5; length -= 5; @@ -410,7 +457,7 @@ snap_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen, * Cisco hardware; the protocol ID is * an Ethernet protocol type. */ - ret = ethertype_print(ndo, et, p, length, caplen); + ret = ethertype_print(ndo, et, p, length, caplen, src, dst); if (ret) return (ret); break; @@ -425,7 +472,7 @@ snap_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen, * but used 0x000000 and an Ethernet * packet type for AARP packets. */ - ret = ethertype_print(ndo, et, p, length, caplen); + ret = ethertype_print(ndo, et, p, length, caplen, src, dst); if (ret) return (ret); } @@ -524,6 +571,33 @@ snap_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen, return (1); } } + if (!ndo->ndo_eflag) { + /* + * Nobody printed the link-layer addresses, so print them, if + * we have any. + */ + if (src != NULL && dst != NULL) { + ND_PRINT((ndo, "%s > %s ", + (src->addr_string)(ndo, src->addr), + (dst->addr_string)(ndo, dst->addr))); + } + /* + * Print the SNAP header, but if the OUI is 000000, don't + * bother printing it, and report the PID as being an + * ethertype. + */ + if (orgcode == 0x000000) { + ND_PRINT((ndo, "SNAP, ethertype %s (0x%04x), length %u: ", + tok2str(ethertype_values, "Unknown", et), + et, length)); + } else { + ND_PRINT((ndo, "SNAP, oui %s (0x%06x), pid %s (0x%04x), length %u: ", + tok2str(oui_values, "Unknown", orgcode), + orgcode, + tok2str(oui_to_struct_tok(orgcode), "Unknown", et), + et, length)); + } + } return (0); trunc: |
