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-rw-r--r--print-pppoe.c206
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diff --git a/print-pppoe.c b/print-pppoe.c
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+/*
+ * 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.
+ *
+ * Original code by Greg Stark <gsstark@mit.edu>
+ */
+
+/* \summary: PPP-over-Ethernet (PPPoE) printer */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "netdissect-stdinc.h"
+
+#include "netdissect-ctype.h"
+
+#define ND_LONGJMP_FROM_TCHECK
+#include "netdissect.h"
+#include "extract.h"
+
+/* Codes */
+enum {
+ PPPOE_PADI = 0x09,
+ PPPOE_PADO = 0x07,
+ PPPOE_PADR = 0x19,
+ PPPOE_PADS = 0x65,
+ PPPOE_PADT = 0xa7
+};
+
+static const struct tok pppoecode2str[] = {
+ { PPPOE_PADI, "PADI" },
+ { PPPOE_PADO, "PADO" },
+ { PPPOE_PADR, "PADR" },
+ { PPPOE_PADS, "PADS" },
+ { PPPOE_PADT, "PADT" },
+ { 0, "" }, /* PPP Data */
+ { 0, NULL }
+};
+
+/* Tags */
+enum {
+ PPPOE_EOL = 0,
+ PPPOE_SERVICE_NAME = 0x0101,
+ PPPOE_AC_NAME = 0x0102,
+ PPPOE_HOST_UNIQ = 0x0103,
+ 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 const struct tok pppoetag2str[] = {
+ { PPPOE_EOL, "EOL" },
+ { PPPOE_SERVICE_NAME, "Service-Name" },
+ { PPPOE_AC_NAME, "AC-Name" },
+ { PPPOE_HOST_UNIQ, "Host-Uniq" },
+ { 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" },
+ { 0, NULL }
+};
+
+#define PPPOE_HDRLEN 6
+#define MAXTAGPRINT 80
+
+void
+pppoe_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p)
+{
+ ndo->ndo_protocol = "pppoe";
+ ndo->ndo_ll_hdr_len += pppoe_print(ndo, p, h->len);
+}
+
+u_int
+pppoe_print(netdissect_options *ndo, const u_char *bp, u_int length)
+{
+ uint16_t pppoe_ver, pppoe_type, pppoe_code, pppoe_sessionid;
+ u_int pppoe_length;
+ const u_char *pppoe_packet, *pppoe_payload;
+
+ ndo->ndo_protocol = "pppoe";
+ if (length < PPPOE_HDRLEN) {
+ ND_PRINT(" (length %u < %u)", length, PPPOE_HDRLEN);
+ goto invalid;
+ }
+ 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 (pppoe_ver != 1) {
+ ND_PRINT(" [ver %u]",pppoe_ver);
+ }
+ if (pppoe_type != 1) {
+ ND_PRINT(" [type %u]",pppoe_type);
+ }
+
+ ND_PRINT("PPPoE %s", tok2str(pppoecode2str, "PAD-%x", pppoe_code));
+ if (pppoe_code == PPPOE_PADI && pppoe_length > 1484 - PPPOE_HDRLEN) {
+ ND_PRINT(" [len %u!]",pppoe_length);
+ }
+ if (pppoe_length > length) {
+ ND_PRINT(" [len %u > %u!]", pppoe_length, length);
+ pppoe_length = length;
+ }
+ if (pppoe_sessionid) {
+ ND_PRINT(" [ses 0x%x]", pppoe_sessionid);
+ }
+
+ if (pppoe_code) {
+ /* PPP session packets don't contain tags */
+ u_short tag_type = 0xffff, tag_len;
+ const u_char *p = pppoe_payload;
+
+ /*
+ * loop invariant:
+ * p points to current tag,
+ * tag_type is previous tag or 0xffff for first iteration
+ */
+ 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) {
+ 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<p+tag_len; v++) {
+ ND_PRINT("%02X", GET_U_1(v));
+ }
+ ND_PRINT("]");
+ }
+
+
+ } else
+ ND_PRINT(" [%s]", tok2str(pppoetag2str,
+ "TAG-0x%x", tag_type));
+
+ p += tag_len;
+ /* p points to next tag */
+ }
+ return PPPOE_HDRLEN;
+ } else {
+ /* PPPoE data */
+ ND_PRINT(" ");
+ return (PPPOE_HDRLEN + ppp_print(ndo, pppoe_payload, pppoe_length));
+ }
+ /* NOTREACHED */
+
+invalid:
+ nd_print_invalid(ndo);
+ return 0;
+}