X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/cfabfb053b4bf5b50f4d98d59053e1cc97ff5014..b51a0dafc7861eb31d21524ec067d7c529a664b8:/print-pppoe.c diff --git a/print-pppoe.c b/print-pppoe.c index d6bafcf6..65518dff 100644 --- a/print-pppoe.c +++ b/print-pppoe.c @@ -17,28 +17,23 @@ * 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. + * + * Original code by Greg Stark */ -#ifndef lint -static const char rcsid[] = -"@(#) $Header: /tcpdump/master/tcpdump/print-pppoe.c,v 1.20 2002-12-18 09:41:17 guy Exp $ (LBL)"; -#endif +/* \summary: PPP-over-Ethernet (PPPoE) printer */ #ifdef HAVE_CONFIG_H -#include "config.h" +#include #endif -#include +#include "netdissect-stdinc.h" -#include -#include +#include "netdissect-ctype.h" -#include "interface.h" -#include "addrtoname.h" -#include "ppp.h" -#include "ethertype.h" -#include "ether.h" -#include "extract.h" /* must come after interface.h */ +#define ND_LONGJMP_FROM_TCHECK +#include "netdissect.h" +#include "extract.h" /* Codes */ enum { @@ -49,7 +44,7 @@ enum { PPPOE_PADT = 0xa7 }; -static struct tok pppoecode2str[] = { +static const struct tok pppoecode2str[] = { { PPPOE_PADI, "PADI" }, { PPPOE_PADO, "PADO" }, { PPPOE_PADR, "PADR" }, @@ -68,12 +63,13 @@ enum { PPPOE_AC_COOKIE = 0x0104, PPPOE_VENDOR = 0x0105, PPPOE_RELAY_SID = 0x0110, + PPPOE_MAX_PAYLOAD = 0x0120, PPPOE_SERVICE_NAME_ERROR = 0x0201, PPPOE_AC_SYSTEM_ERROR = 0x0202, PPPOE_GENERIC_ERROR = 0x0203 }; -static struct tok pppoetag2str[] = { +static const struct tok pppoetag2str[] = { { PPPOE_EOL, "EOL" }, { PPPOE_SERVICE_NAME, "Service-Name" }, { PPPOE_AC_NAME, "AC-Name" }, @@ -81,6 +77,7 @@ static struct tok pppoetag2str[] = { { PPPOE_AC_COOKIE, "AC-Cookie" }, { PPPOE_VENDOR, "Vendor-Specific" }, { PPPOE_RELAY_SID, "Relay-Session-ID" }, + { PPPOE_MAX_PAYLOAD, "PPP-Max-Payload" }, { PPPOE_SERVICE_NAME_ERROR, "Service-Name-Error" }, { PPPOE_AC_SYSTEM_ERROR, "AC-System-Error" }, { PPPOE_GENERIC_ERROR, "Generic-Error" }, @@ -88,87 +85,54 @@ static struct tok pppoetag2str[] = { }; #define PPPOE_HDRLEN 6 +#define MAXTAGPRINT 80 void -pppoe_if_print(u_char *user _U_, const struct pcap_pkthdr *h, - register const u_char *p) +pppoe_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p) { - register u_int length = h->len; - register u_int caplen = h->caplen; - u_int hdr_len; - - ++infodelay; - ts_print(&h->ts); - - /* - * Some printers want to check that they're not walking off the - * end of the packet. - * Rather than pass it all the way down, we set this global. - */ - snapend = p + caplen; - - hdr_len = pppoe_print(p, length); - - /* - * If "-x" was specified, print packet data in hex. - */ - if (xflag) - default_print_packet(p, caplen, hdr_len); - - putchar('\n'); - - --infodelay; - if (infoprint) - info(0); + ndo->ndo_protocol = "pppoe"; + ndo->ndo_ll_hdr_len += pppoe_print(ndo, p, h->len); } u_int -pppoe_print(register const u_char *bp, u_int length) +pppoe_print(netdissect_options *ndo, const u_char *bp, u_int length) { - u_short pppoe_ver, pppoe_type, pppoe_code, pppoe_sessionid, pppoe_length; + uint16_t pppoe_ver, pppoe_type, pppoe_code, pppoe_sessionid; + u_int pppoe_length; const u_char *pppoe_packet, *pppoe_payload; - pppoe_packet = bp; - if (pppoe_packet > snapend) { - printf("[|pppoe]"); - return (PPPOE_HDRLEN); + ndo->ndo_protocol = "pppoe"; + if (length < PPPOE_HDRLEN) { + ND_PRINT(" (length %u < %u)", length, PPPOE_HDRLEN); + goto invalid; } - - pppoe_ver = (pppoe_packet[0] & 0xF0) >> 4; - pppoe_type = (pppoe_packet[0] & 0x0F); - pppoe_code = pppoe_packet[1]; - pppoe_sessionid = EXTRACT_16BITS(pppoe_packet + 2); - pppoe_length = EXTRACT_16BITS(pppoe_packet + 4); + length -= PPPOE_HDRLEN; + pppoe_packet = bp; + ND_TCHECK_LEN(pppoe_packet, PPPOE_HDRLEN); + pppoe_ver = (GET_U_1(pppoe_packet) & 0xF0) >> 4; + pppoe_type = (GET_U_1(pppoe_packet) & 0x0F); + pppoe_code = GET_U_1(pppoe_packet + 1); + pppoe_sessionid = GET_BE_U_2(pppoe_packet + 2); + pppoe_length = GET_BE_U_2(pppoe_packet + 4); pppoe_payload = pppoe_packet + PPPOE_HDRLEN; - if (snapend < pppoe_payload) { - printf(" truncated PPPoE"); - return (PPPOE_HDRLEN); - } - if (pppoe_ver != 1) { - printf(" [ver %d]",pppoe_ver); + ND_PRINT(" [ver %u]",pppoe_ver); } if (pppoe_type != 1) { - printf(" [type %d]",pppoe_type); + ND_PRINT(" [type %u]",pppoe_type); } - printf("PPPoE %s", tok2str(pppoecode2str, "PAD-%x", pppoe_code)); + ND_PRINT("PPPoE %s", tok2str(pppoecode2str, "PAD-%x", pppoe_code)); if (pppoe_code == PPPOE_PADI && pppoe_length > 1484 - PPPOE_HDRLEN) { - printf(" [len %d!]",pppoe_length); + ND_PRINT(" [len %u!]",pppoe_length); } - if (pppoe_sessionid) { - printf(" [ses 0x%x]", pppoe_sessionid); + if (pppoe_length > length) { + ND_PRINT(" [len %u > %u!]", pppoe_length, length); + pppoe_length = length; } - - if (pppoe_payload + pppoe_length < snapend) { -#if 0 - const u_char *x = pppoe_payload + pppoe_length; - printf(" [length %d (%d extra bytes)]", - pppoe_length, snapend - pppoe_payload - pppoe_length); - default_print(x, snapend - x); -#endif - snapend = pppoe_payload+pppoe_length; + if (pppoe_sessionid) { + ND_PRINT(" [ses 0x%x]", pppoe_sessionid); } if (pppoe_code) { @@ -178,47 +142,65 @@ pppoe_print(register const u_char *bp, u_int length) /* * loop invariant: - * p points to next tag, + * p points to current tag, * tag_type is previous tag or 0xffff for first iteration */ - while (tag_type && p + 4 < pppoe_payload + length && - p + 4 < snapend) { - tag_type = EXTRACT_16BITS(p); - tag_len = EXTRACT_16BITS(p + 2); + while (tag_type && p < pppoe_payload + pppoe_length) { + tag_type = GET_BE_U_2(p); + tag_len = GET_BE_U_2(p + 2); p += 4; /* p points to tag_value */ if (tag_len) { - int isascii = 1; - const u_char *v = p; - u_short l; - - for (v = p; v < p + tag_len; v++) - if (*v >= 127 || *v < 32) { - isascii = 0; - break; + unsigned ascii_count = 0, garbage_count = 0; + const u_char *v; + char tag_str[MAXTAGPRINT]; + unsigned tag_str_len = 0; + + /* TODO print UTF-8 decoded text */ + ND_TCHECK_LEN(p, tag_len); + for (v = p; v < p + tag_len && tag_str_len < MAXTAGPRINT-1; v++) + if (ND_ASCII_ISPRINT(GET_U_1(v))) { + tag_str[tag_str_len++] = GET_U_1(v); + ascii_count++; + } else { + tag_str[tag_str_len++] = '.'; + garbage_count++; + } + tag_str[tag_str_len] = 0; + + if (ascii_count > garbage_count) { + ND_PRINT(" [%s \"%*.*s\"]", + tok2str(pppoetag2str, "TAG-0x%x", tag_type), + (int)tag_str_len, + (int)tag_str_len, + tag_str); + } else { + /* Print hex, not fast to abuse printf but this doesn't get used much */ + ND_PRINT(" [%s 0x", tok2str(pppoetag2str, "TAG-0x%x", tag_type)); + for (v=p; v