Address Michael's comments.

[tcpdump] / print-pppoe.c

diff --git a/print-pppoe.c b/print-pppoe.c
index 3456225bd33d771b74871463528ab2aa0783b53a..bcc976c4b7981c768049978263bf417952f67ece 100644 (file)
--- a/print-pppoe.c
+++ b/print-pppoe.c
@@ -17,11 +17,13 @@
  * 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.
  * 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 <[email protected]> 

  */
 
 #ifndef lint
  */
 
 #ifndef lint

-static const char rcsid[] =
-"@(#) $Header: /tcpdump/master/tcpdump/print-pppoe.c,v 1.18 2002-09-05 21:25:45 guy Exp $ (LBL)";
+static const char rcsid[] _U_ =
+"@(#) $Header: /tcpdump/master/tcpdump/print-pppoe.c,v 1.31 2005-04-26 19:48:38 guy Exp $ (LBL)";

 #endif
 
 #ifdef HAVE_CONFIG_H
 #endif
 
 #ifdef HAVE_CONFIG_H


@@ -68,6 +70,7 @@ enum {
        PPPOE_AC_COOKIE = 0x0104,
        PPPOE_VENDOR = 0x0105,
        PPPOE_RELAY_SID = 0x0110,
        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
        PPPOE_SERVICE_NAME_ERROR = 0x0201,
        PPPOE_AC_SYSTEM_ERROR = 0x0202,
        PPPOE_GENERIC_ERROR = 0x0203


@@ -81,6 +84,7 @@ static struct tok pppoetag2str[] = {
        { PPPOE_AC_COOKIE, "AC-Cookie" },
        { PPPOE_VENDOR, "Vendor-Specific" },
        { PPPOE_RELAY_SID, "Relay-Session-ID" },
        { 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" },
        { PPPOE_SERVICE_NAME_ERROR, "Service-Name-Error" },
        { PPPOE_AC_SYSTEM_ERROR, "AC-System-Error" },
        { PPPOE_GENERIC_ERROR, "Generic-Error" },


@@ -88,54 +92,28 @@ static struct tok pppoetag2str[] = {
 };
 
 #define PPPOE_HDRLEN 6
 };
 
 #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)
+u_int
+pppoe_if_print(const struct pcap_pkthdr *h, register 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 get back at the link level addresses,
-        * and/or check that they're not walking off the end of the packet.
-        * Rather than pass them all the way down, we set these globals.
-        */
-       packetp = p;
-       snapend = p + caplen;
-
-       hdr_len = pppoe_print(p, length);
-
-       /*
-        * If "-x" was specified, print stuff past the PPPoE and PPP headers,
-        * if there's anything to print.
-        */
-       if (xflag && caplen > hdr_len)
-               default_print(p + hdr_len, caplen - hdr_len);
-
-       putchar('\n');
-
-       --infodelay;
-       if (infoprint)
-               info(0);
+       return (pppoe_print(p, h->len));

 }
 
 u_int
 pppoe_print(register const u_char *bp, u_int length)
 {
 }
 
 u_int
 pppoe_print(register const u_char *bp, u_int length)
 {

-       u_short pppoe_ver, pppoe_type, pppoe_code, pppoe_sessionid, pppoe_length;
+       u_int16_t pppoe_ver, pppoe_type, pppoe_code, pppoe_sessionid;
+       u_int pppoe_length;

        const u_char *pppoe_packet, *pppoe_payload;
 
        const u_char *pppoe_packet, *pppoe_payload;
 

-       pppoe_packet = bp;
-       if (pppoe_packet > snapend) {
-               printf("[|pppoe]");
-               return (PPPOE_HDRLEN);
+       if (length < PPPOE_HDRLEN) {
+               (void)printf("truncated-pppoe %u", length);
+               return (length);

        }
        }

-
+       length -= PPPOE_HDRLEN;
+       pppoe_packet = bp;
+       TCHECK2(*pppoe_packet, PPPOE_HDRLEN);

        pppoe_ver  = (pppoe_packet[0] & 0xF0) >> 4;
        pppoe_type  = (pppoe_packet[0] & 0x0F);
        pppoe_code = pppoe_packet[1];
        pppoe_ver  = (pppoe_packet[0] & 0xF0) >> 4;
        pppoe_type  = (pppoe_packet[0] & 0x0F);
        pppoe_code = pppoe_packet[1];


@@ -143,11 +121,6 @@ pppoe_print(register const u_char *bp, u_int length)
        pppoe_length    = EXTRACT_16BITS(pppoe_packet + 4);
        pppoe_payload = pppoe_packet + PPPOE_HDRLEN;
 
        pppoe_length    = EXTRACT_16BITS(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);
        }
        if (pppoe_ver != 1) {
                printf(" [ver %d]",pppoe_ver);
        }


@@ -157,22 +130,16 @@ pppoe_print(register const u_char *bp, u_int length)
 
        printf("PPPoE %s", tok2str(pppoecode2str, "PAD-%x", pppoe_code));
        if (pppoe_code == PPPOE_PADI && pppoe_length > 1484 - PPPOE_HDRLEN) {
 
        printf("PPPoE %s", tok2str(pppoecode2str, "PAD-%x", pppoe_code));
        if (pppoe_code == PPPOE_PADI && pppoe_length > 1484 - PPPOE_HDRLEN) {

-               printf(" [len %d!]",pppoe_length);
+               printf(" [len %u!]",pppoe_length);
+       }
+       if (pppoe_length > length) {
+               printf(" [len %u > %u!]", pppoe_length, length);
+               pppoe_length = length;

        }
        if (pppoe_sessionid) {
                printf(" [ses 0x%x]", pppoe_sessionid);
        }
 
        }
        if (pppoe_sessionid) {
                printf(" [ses 0x%x]", pppoe_sessionid);
        }
 

-       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_code) {
                /* PPP session packets don't contain tags */
                u_short tag_type = 0xffff, tag_len;
        if (pppoe_code) {
                /* PPP session packets don't contain tags */
                u_short tag_type = 0xffff, tag_len;


@@ -180,36 +147,50 @@ pppoe_print(register const u_char *bp, u_int length)
 
                /*
                 * loop invariant:
 
                /*
                 * loop invariant:

-                * p points to next tag,
+                * p points to current tag,

                 * tag_type is previous tag or 0xffff for first iteration
                 */
                 * tag_type is previous tag or 0xffff for first iteration
                 */

-               while (tag_type && p + 4 < pppoe_payload + length &&
-                   p + 4 < snapend) {
+               while (tag_type && p < pppoe_payload + pppoe_length) {
+                       TCHECK2(*p, 4);

                        tag_type = EXTRACT_16BITS(p);
                        tag_len = EXTRACT_16BITS(p + 2);
                        p += 4;
                        /* p points to tag_value */
 
                        if (tag_len) {
                        tag_type = EXTRACT_16BITS(p);
                        tag_len = EXTRACT_16BITS(p + 2);
                        p += 4;
                        /* p points to tag_value */
 
                        if (tag_len) {

-                               int isascii = 1;
+                               unsigned isascii = 0, isgarbage = 0;

                                const u_char *v = p;
                                const u_char *v = p;

-                               u_short l;
-
-                               for (v = p; v < p + tag_len; v++)
-                                       if (*v >= 127 || *v < 32) {
-                                               isascii = 0;
-                                               break;
+                               char tag_str[MAXTAGPRINT];
+                               unsigned tag_str_len = 0;
+
+                               /* TODO print UTF-8 decoded text */
+                               TCHECK2(*p, tag_len);
+                               for (v = p; v < p + tag_len && tag_str_len < MAXTAGPRINT-1; v++)
+                                       if (*v >= 32 && *v < 127) {
+                                               tag_str[tag_str_len++] = *v;
+                                               isascii++;
+                                       } else {
+                                               tag_str[tag_str_len++] = '.';
+                                               isgarbage++;

                                        }
                                        }

+                               tag_str[tag_str_len] = 0;

 
 

-                               /* TODO print UTF8 decoded text */
-                               if (isascii) {
-                                       l = (tag_len < 80 ? tag_len : 80);
+                               if (isascii > isgarbage) {

                                        printf(" [%s \"%*.*s\"]",
                                        printf(" [%s \"%*.*s\"]",

-                                           tok2str(pppoetag2str, "TAG-0x%x", tag_type),
-                                           l, l, p);
-                               } else
-                                       printf(" [%s UTF8]",
-                                           tok2str(pppoetag2str, "TAG-0x%x", tag_type));
+                                              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 */
+                                       printf(" [%s 0x", tok2str(pppoetag2str, "TAG-0x%x", tag_type));
+                                       for (v=p; v<p+tag_len; v++) {
+                                               printf("%02X", *v);
+                                       }
+                                       printf("]");
+                               }
+                               
+

                        } else
                                printf(" [%s]", tok2str(pppoetag2str,
                                    "TAG-0x%x", tag_type));
                        } else
                                printf(" [%s]", tok2str(pppoetag2str,
                                    "TAG-0x%x", tag_type));


@@ -223,4 +204,8 @@ pppoe_print(register const u_char *bp, u_int length)
                printf(" ");
                return (PPPOE_HDRLEN + ppp_print(pppoe_payload, pppoe_length));
        }
                printf(" ");
                return (PPPOE_HDRLEN + ppp_print(pppoe_payload, pppoe_length));
        }

+
+trunc:
+       printf("[|pppoe]");
+       return (PPPOE_HDRLEN);

 }
 }