X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/d29f3dab95d8b28a62848fcb043b8ba40348bc3d..refs/pull/471/head:/print-llc.c diff --git a/print-llc.c b/print-llc.c index c5bda71e..aaaac8e1 100644 --- a/print-llc.c +++ b/print-llc.c @@ -26,14 +26,11 @@ #include "config.h" #endif -#include +#include -#include -#include - -#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" @@ -126,7 +123,7 @@ static const struct tok null_values[] = { }; struct oui_tok { - u_int32_t oui; + uint32_t oui; const struct tok *tok; }; @@ -140,23 +137,31 @@ 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(const u_char *p, u_int length, u_int caplen, - const u_char *esrc, const u_char *edst, u_short *extracted_ethertype) +llc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen, + const u_char *esrc, const u_char *edst) { - u_int8_t dsap_field, dsap, ssap_field, ssap; - u_int16_t control; + 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) { - (void)printf("[|llc]"); - default_print((u_char *)p, caplen); - return(0); + ND_PRINT((ndo, "[|llc]")); + 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 +179,21 @@ llc_print(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) { - (void)printf("[|llc]"); - default_print((u_char *)p, caplen); - return(0); + ND_PRINT((ndo, "[|llc]")); + 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 +201,7 @@ llc_print(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) { @@ -208,42 +220,73 @@ llc_print(const u_char *p, u_int length, u_int caplen, * least one capture file.) */ - if (eflag) - printf("IPX 802.3: "); + if (ndo->ndo_eflag) + ND_PRINT((ndo, "IPX 802.3: ")); - ipx_print(gndo, p, length); - return (1); + ipx_print(ndo, p, length); + return (0); /* no LLC header */ } dsap = dsap_field & ~LLC_IG; ssap = ssap_field & ~LLC_GSAP; - if (eflag) { - printf("LLC, dsap %s (0x%02x) %s, ssap %s (0x%02x) %s", + if (ndo->ndo_eflag) { + ND_PRINT((ndo, "LLC, dsap %s (0x%02x) %s, ssap %s (0x%02x) %s", tok2str(llc_values, "Unknown", dsap), dsap, tok2str(llc_ig_flag_values, "Unknown", dsap_field & LLC_IG), tok2str(llc_values, "Unknown", ssap), ssap, - tok2str(llc_flag_values, "Unknown", ssap_field & LLC_GSAP)); + tok2str(llc_flag_values, "Unknown", ssap_field & LLC_GSAP))); if (is_u) { - printf(", ctrl 0x%02x: ", control); + ND_PRINT((ndo, ", ctrl 0x%02x: ", control)); } else { - printf(", ctrl 0x%04x: ", control); + ND_PRINT((ndo, ", ctrl 0x%04x: ", control)); } } + /* + * 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, esrc, edst, 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(p+3, length-3); - return (1); + stp_print(ndo, p, length); + return (hdrlen); } if (ssap == LLCSAP_IP && dsap == LLCSAP_IP && control == LLC_UI) { - ip_print(gndo, 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 && @@ -252,17 +295,15 @@ llc_print(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 (eflag) - printf("IPX 802.2: "); + if (ndo->ndo_eflag) + ND_PRINT((ndo, "IPX 802.2: ")); - ipx_print(gndo, 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)) { /* @@ -275,120 +316,111 @@ llc_print(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(control, p, length); - return (1); + netbeui_print(ndo, control, p, length); + return (hdrlen); } #endif if (ssap == LLCSAP_ISONS && dsap == LLCSAP_ISONS && control == LLC_UI) { - isoclns_print(p + 3, length - 3, caplen - 3); - return (1); + isoclns_print(ndo, p, length, caplen); + return (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? - */ - ret = snap_print(p+3, length-3, caplen-3, 2); - if (ret) - return (ret); - } - - if (!eflag) { + if (!ndo->ndo_eflag) { if (ssap == dsap) { if (esrc == NULL || edst == NULL) - (void)printf("%s ", tok2str(llc_values, "Unknown DSAP 0x%02x", dsap)); + ND_PRINT((ndo, "%s ", tok2str(llc_values, "Unknown DSAP 0x%02x", dsap))); else - (void)printf("%s > %s %s ", - etheraddr_string(esrc), - etheraddr_string(edst), - tok2str(llc_values, "Unknown DSAP 0x%02x", dsap)); + ND_PRINT((ndo, "%s > %s %s ", + etheraddr_string(ndo, esrc), + etheraddr_string(ndo, edst), + tok2str(llc_values, "Unknown DSAP 0x%02x", dsap))); } else { if (esrc == NULL || edst == NULL) - (void)printf("%s > %s ", + ND_PRINT((ndo, "%s > %s ", tok2str(llc_values, "Unknown SSAP 0x%02x", ssap), - tok2str(llc_values, "Unknown DSAP 0x%02x", dsap)); + tok2str(llc_values, "Unknown DSAP 0x%02x", dsap))); else - (void)printf("%s %s > %s %s ", - etheraddr_string(esrc), + ND_PRINT((ndo, "%s %s > %s %s ", + etheraddr_string(ndo, esrc), tok2str(llc_values, "Unknown SSAP 0x%02x", ssap), - etheraddr_string(edst), - tok2str(llc_values, "Unknown DSAP 0x%02x", dsap)); + etheraddr_string(ndo, edst), + tok2str(llc_values, "Unknown DSAP 0x%02x", dsap))); } } if (is_u) { - printf("Unnumbered, %s, Flags [%s], length %u", + 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 (*p == LLC_XID_FI) { - printf(": %02x %02x", p[1], p[2]); + ND_PRINT((ndo, ": %02x %02x", p[1], p[2])); + return (hdrlen); } } } else { if ((control & LLC_S_FMT) == LLC_S_FMT) { - (void)printf("Supervisory, %s, rcv seq %u, Flags [%s], length %u", + ND_PRINT((ndo, "Supervisory, %s, rcv seq %u, Flags [%s], length %u", 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 { - (void)printf("Information, send seq %u, rcv seq %u, Flags [%s], length %u", + 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 (-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(1); + return (tok); } int -snap_print(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 u_char *esrc, const u_char *edst, u_int bridge_pad) { - u_int32_t orgcode; + uint32_t orgcode; register u_short et; register int ret; - TCHECK2(*p, 5); + ND_TCHECK2(*p, 5); + if (caplen < 5 || length < 5) + goto trunc; orgcode = EXTRACT_24BITS(p); et = EXTRACT_16BITS(p + 3); - if (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; - } - } - (void)printf("oui %s (0x%06x), %s %s (0x%04x): ", + if (ndo->ndo_eflag) { + /* + * 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; @@ -403,7 +435,7 @@ snap_print(const u_char *p, u_int length, u_int caplen, u_int bridge_pad) * Cisco hardware; the protocol ID is * an Ethernet protocol type. */ - ret = ethertype_print(gndo, et, p, length, caplen); + ret = ethertype_print(ndo, et, p, length, caplen); if (ret) return (ret); break; @@ -418,7 +450,7 @@ snap_print(const u_char *p, u_int length, u_int caplen, u_int bridge_pad) * but used 0x000000 and an Ethernet * packet type for AARP packets. */ - ret = ethertype_print(gndo, et, p, length, caplen); + ret = ethertype_print(ndo, et, p, length, caplen); if (ret) return (ret); } @@ -427,24 +459,25 @@ snap_print(const u_char *p, u_int length, u_int caplen, u_int bridge_pad) case OUI_CISCO: switch (et) { case PID_CISCO_CDP: - cdp_print(p, length, caplen); + cdp_print(ndo, p, length, caplen); return (1); case PID_CISCO_DTP: - dtp_print(gndo, p, length); + dtp_print(ndo, p, length); return (1); case PID_CISCO_UDLD: - udld_print(gndo, p, length); + udld_print(ndo, p, length); return (1); case PID_CISCO_VTP: - vtp_print(p, length); + vtp_print(ndo, p, length); return (1); case PID_CISCO_PVST: case PID_CISCO_VLANBRIDGE: - stp_print(p, length); + stp_print(ndo, p, length); return (1); default: break; } + break; case OUI_RFC2684: switch (et) { @@ -458,7 +491,7 @@ snap_print(const u_char *p, u_int length, u_int caplen, u_int bridge_pad) /* * Skip the padding. */ - TCHECK2(*p, bridge_pad); + ND_TCHECK2(*p, bridge_pad); caplen -= bridge_pad; length -= bridge_pad; p += bridge_pad; @@ -466,7 +499,7 @@ snap_print(const u_char *p, u_int length, u_int caplen, u_int bridge_pad) /* * What remains is an Ethernet packet. */ - ether_print(gndo, p, length, caplen, NULL, NULL); + ether_print(ndo, p, length, caplen, NULL, NULL); return (1); case PID_RFC2684_802_5_FCS: @@ -479,7 +512,7 @@ snap_print(const u_char *p, u_int length, u_int caplen, u_int bridge_pad) * Skip the padding, but not the Access * Control field. */ - TCHECK2(*p, bridge_pad); + ND_TCHECK2(*p, bridge_pad); caplen -= bridge_pad; length -= bridge_pad; p += bridge_pad; @@ -488,7 +521,7 @@ snap_print(const u_char *p, u_int length, u_int caplen, u_int bridge_pad) * What remains is an 802.5 Token Ring * packet. */ - token_print(p, length, caplen); + token_print(ndo, p, length, caplen); return (1); case PID_RFC2684_FDDI_FCS: @@ -500,7 +533,7 @@ snap_print(const u_char *p, u_int length, u_int caplen, u_int bridge_pad) /* * Skip the padding. */ - TCHECK2(*p, bridge_pad + 1); + ND_TCHECK2(*p, bridge_pad + 1); caplen -= bridge_pad + 1; length -= bridge_pad + 1; p += bridge_pad + 1; @@ -508,18 +541,45 @@ snap_print(const u_char *p, u_int length, u_int caplen, u_int bridge_pad) /* * What remains is an FDDI packet. */ - fddi_print(p, length, caplen); + fddi_print(ndo, p, length, caplen); return (1); case PID_RFC2684_BPDU: - stp_print(p, length); + stp_print(ndo, p, length); return (1); } } + if (!ndo->ndo_eflag) { + /* + * Nobody printed the MAC addresses, so print them, if + * we have any. + */ + if (esrc != NULL && edst != NULL) { + ND_PRINT((ndo, "%s > %s ", + etheraddr_string(ndo, esrc), + etheraddr_string(ndo, edst))); + } + /* + * 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: - (void)printf("[|snap]"); + ND_PRINT((ndo, "[|snap]")); return (1); }