]> The Tcpdump Group git mirrors - tcpdump/blobdiff - print-fr.c
add tracefiles for infinite loop testing
[tcpdump] / print-fr.c
index a2271d67b0fb0edde0598f18c9d8e2d126f18133..899a633879865ceb96e0f1122a447de4210d86af 100644 (file)
@@ -20,8 +20,8 @@
  */
 
 #ifndef lint
-static const char rcsid[] =
-       "@(#)$Header: /tcpdump/master/tcpdump/print-fr.c,v 1.6 2002-09-05 21:25:41 guy Exp $ (LBL)";
+static const char rcsid[] _U_ =
+       "@(#)$Header: /tcpdump/master/tcpdump/print-fr.c,v 1.17.2.4 2004-04-02 06:53:51 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -30,41 +30,19 @@ static const char rcsid[] =
 
 #include <tcpdump-stdinc.h>
 
-struct mbuf;
-struct rtentry;
-
 #include <stdio.h>
 #include <string.h>
 #include <pcap.h>
 
-#include "interface.h"
 #include "addrtoname.h"
+#include "interface.h"
 #include "ethertype.h"
 #include "extract.h"
 
-static void q933_print(const u_char *, int);
-
-#define FR_CR_BIT      0x02
-#define FR_EA_BIT(p)   ((p)&0x01)
-#define FR_FECN                0x08
-#define FR_BECN                0x04
-#define FR_DE          0x02
-#define FR_DLCI(b0, b1)        ((((b0)&0xFC)<<2)+(((b1)&0xF0)>>4))
-
-/* find out how many bytes are there in a frame */
-static u_int
-fr_addr_len(const u_char *p)
-{
-       u_int i=0;
-       
-       while (!FR_EA_BIT(p[i]) && i++ && !FR_EA_BIT(p[i+1])) i++;
-       return (i+1);
-}
+static void lmi_print(const u_char *, u_int);
 
-/* the following is for framerelay */
-#define NLPID_LEN      1       /* NLPID is one byte long */
-#define NLPID_Q933      0x08
-#define NLPID_LMI       0x09
+#define NLPID_LMI       0x08   /* ANSI T1.617 Annex D or ITU-T Q.933 Annex A */
+#define NLPID_CISCO_LMI 0x09   /* The original, aka Cisco, aka Gang of Four */
 #define NLPID_SNAP      0x80
 #define NLPID_CLNP      0x81
 #define NLPID_ESIS      0x82
@@ -72,8 +50,62 @@ fr_addr_len(const u_char *p)
 #define NLPID_CONS      0x84
 #define NLPID_IDRP      0x85
 #define NLPID_X25_ESIS  0x8a
+#define NLPID_IPV6      0x8e
 #define NLPID_IP        0xcc
 
+#define FR_EA_BIT      0x01
+
+
+/* Finds out Q.922 address length, DLCI and flags. Returns 0 on success */
+static int parse_q922_addr(const u_char *p, u_int *dlci, u_int *addr_len,
+                          char **flags_ptr)
+{
+       static char flags[32];
+       size_t len;
+
+       if ((p[0] & FR_EA_BIT))
+               return -1;
+
+       *flags_ptr = flags;
+       *addr_len = 2;
+       *dlci = ((p[0] & 0xFC) << 2) | ((p[1] & 0xF0) >> 4);
+
+       strcpy(flags, (p[0] & 0x02) ? "C!, " : "");
+       if (p[1] & 0x08)
+               strcat(flags, "FECN, ");
+       if (p[1] & 0x04)
+               strcat(flags, "BECN, ");
+       if (p[1] & 0x02)
+               strcat(flags, "DE, ");
+
+       len = strlen(flags);
+       if (len > 1)
+               flags[len - 2] = '\x0'; /* delete trailing comma and space */
+
+       if (p[1] & FR_EA_BIT)
+               return 0;       /* 2-byte Q.922 address */
+
+       p += 2;
+       (*addr_len)++;          /* 3- or 4-byte Q.922 address */
+       if ((p[0] & FR_EA_BIT) == 0) {
+               *dlci = (*dlci << 7) | (p[0] >> 1);
+               (*addr_len)++;  /* 4-byte Q.922 address */
+               p++;
+       }
+
+       if ((p[0] & FR_EA_BIT) == 0)
+               return -1; /* more than 4 bytes of Q.922 address? */
+
+       if (p[0] & 0x02) {
+               len = strlen(flags);
+               snprintf(flags + len, sizeof(flags) - len,
+                        "%sdlcore %x", len ? ", " : "", p[0] >> 2);
+       } else
+               *dlci = (*dlci << 6) | (p[0] >> 2);
+
+       return 0;
+}
+
 
 static const char *fr_nlpids[256];
 
@@ -86,8 +118,8 @@ init_fr_nlpids(void)
        if (!fr_nlpid_flag) {
                for (i=0; i < 256; i++)
                        fr_nlpids[i] = NULL;
-               fr_nlpids[NLPID_Q933] = "Q.933";
                fr_nlpids[NLPID_LMI] = "LMI";
+               fr_nlpids[NLPID_CISCO_LMI] = "Cisco LMI";
                fr_nlpids[NLPID_SNAP] = "SNAP";
                fr_nlpids[NLPID_CLNP] = "CLNP";
                fr_nlpids[NLPID_ESIS] = "ESIS";
@@ -100,11 +132,8 @@ init_fr_nlpids(void)
        fr_nlpid_flag = 1;
 }
 
-/* Framerelay packet structure */
+/* Frame Relay packet structure, with flags and CRC removed
 
-/*
-                  +---------------------------+
-                  |    flag (7E hexadecimal)  |
                   +---------------------------+
                   |       Q.922 Address*      |
                   +--                       --+
@@ -123,62 +152,20 @@ init_fr_nlpids(void)
                   |             .             |
                   |             .             |
                   +---------------------------+
-                  |   Frame Check Sequence    |
-                  +--           .           --+
-                  |       (two octets)        |
-                  +---------------------------+
-                  |   flag (7E hexadecimal)   |
-                  +---------------------------+
 
            * Q.922 addresses, as presently defined, are two octets and
              contain a 10-bit DLCI.  In some networks Q.922 addresses
              may optionally be increased to three or four octets.
-
 */
 
-#define FR_PROTOCOL(p) fr_protocol((p))
-
 static u_int
-fr_hdrlen(const u_char *p)
-{
-       u_int hlen;
-       hlen = fr_addr_len(p)+1;  /* addr_len + 0x03 + padding */
-       if (p[hlen])
-               return hlen;
-       else
-               return hlen+1;
-}
-
-#define LAYER2_LEN(p) (fr_hdrlen((p))+NLPID_LEN)
-
-static int
-fr_protocol(const u_char *p)
+fr_hdrlen(const u_char *p, u_int addr_len, u_int caplen)
 {
-       int hlen;
-       
-       hlen = fr_addr_len(p) + 1;
-       if (p[hlen])  /* check for padding */
-               return p[hlen];
+       if ((caplen > addr_len + 1 /* UI */ + 1 /* pad */) &&
+           !p[addr_len + 1] /* pad exist */)
+               return addr_len + 1 /* UI */ + 1 /* pad */ + 1 /* NLPID */;
        else 
-               return p[hlen+1];
-}
-
-static char *
-fr_flags(const u_char *p)
-{
-       static char flags[1+1+4+1+4+1+2+1];
-
-       if (p[0] & FR_CR_BIT)
-               strcpy(flags, "C");
-       else
-               strcpy(flags, "R");
-       if (p[1] & FR_FECN)
-               strcat(flags, ",FECN");
-       if (p[1] & FR_BECN)
-               strcat(flags, ",BECN");
-       if (p[1] & FR_DE)
-               strcat(flags, ",DE");
-       return flags;
+               return addr_len + 1 /* UI */ + 1 /* NLPID */;
 }
 
 static const char *
@@ -186,77 +173,90 @@ fr_protostring(u_int8_t proto)
 {
        static char buf[5+1+2+1];
 
+       init_fr_nlpids();
+
        if (nflag || fr_nlpids[proto] == NULL) {
-               sprintf(buf, "proto-%02x", proto);
+               snprintf(buf, sizeof(buf), "proto %02x", proto);
                return buf;
        }
        return fr_nlpids[proto];
 }
 
 static void
-fr_hdr_print(const u_char *p, int length)
+fr_hdr_print(int length, u_int dlci, char *flags, u_char nlpid)
 {
-       u_int8_t proto;
-
-       proto = FR_PROTOCOL(p);
-
-       init_fr_nlpids();
-       /* this is kinda kludge since it assumed that DLCI is two bytes. */
        if (qflag)
-               (void)printf("DLCI-%u-%s %d: ",
-                            FR_DLCI(p[0], p[1]), fr_flags(p), length);
+               (void)printf("DLCI %u, %s%slength %d: ",
+                            dlci, flags, *flags ? ", " : "", length);
        else
-               (void)printf("DLCI-%u-%s %s %d: ",
-                            FR_DLCI(p[0], p[1]), fr_flags(p),
-                            fr_protostring(proto), length);
+               (void)printf("DLCI %u, %s%s%s, length %d: ",
+                            dlci, flags, *flags ? ", " : "",
+                            fr_protostring(nlpid), length);
 }
 
-void
-fr_if_print(u_char *user _U_, const struct pcap_pkthdr *h,
-            register const u_char *p)
+u_int
+fr_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_char protocol;
-       int layer2_len;
        u_short extracted_ethertype;
        u_int32_t orgcode;
        register u_short et;
+       u_int dlci;
+       u_int addr_len;
+       u_char nlpid;
+       u_int hdr_len;
+       char *flags;
+
+       if (caplen < 4) {       /* minimum frame header length */
+               printf("[|fr]");
+               return caplen;
+       }
 
-       ts_print(&h->ts);
+       if (parse_q922_addr(p, &dlci, &addr_len, &flags)) {
+               printf("Invalid Q.922 address");
+               return caplen;
+       }
+
+       hdr_len = fr_hdrlen(p, addr_len, caplen);
 
-       if (caplen < fr_hdrlen(p)) {
+       if (caplen < hdr_len) {
                printf("[|fr]");
-               goto out;
+               return caplen;
        }
 
-       /*
-        * 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;
+       if (p[addr_len] != 0x03)
+               printf("UI %02x! ", p[addr_len]);
 
-       if (eflag)
-               fr_hdr_print(p, length);
+       if (!p[addr_len + 1]) { /* pad byte should be used with 3-byte Q.922 */
+               if (addr_len != 3)
+                       printf("Pad! ");
+       } else if (addr_len == 3)
+               printf("No pad! ");
 
-       protocol = FR_PROTOCOL(p);
-       layer2_len = LAYER2_LEN(p);
-       p += layer2_len;
-       length -= layer2_len;
-       caplen -= layer2_len;
+       nlpid = p[hdr_len - 1];
 
-       switch (protocol) {
+       p += hdr_len;
+       length -= hdr_len;
+       caplen -= hdr_len;
+
+       if (eflag)
+               fr_hdr_print(length, dlci, flags, nlpid);
 
+       switch (nlpid) {
        case NLPID_IP:
                ip_print(p, length);
                break;
 
+#ifdef INET6
+       case NLPID_IPV6:
+               ip6_print(p, length);
+               break;
+#endif
        case NLPID_CLNP:
        case NLPID_ESIS:
        case NLPID_ISIS:
-               isoclns_print(p, length, caplen, NULL, NULL);
+               isoclns_print(p, length, caplen);
                break;
 
        case NLPID_SNAP:
@@ -267,31 +267,30 @@ fr_if_print(u_char *user _U_, const struct pcap_pkthdr *h,
                           0) == 0) {
                        /* ether_type not known, print raw packet */
                        if (!eflag)
-                               fr_hdr_print(p - layer2_len, length + layer2_len);
+                               fr_hdr_print(length + hdr_len,
+                                            dlci, flags, nlpid);
                        if (extracted_ethertype) {
                                printf("(SNAP %s) ",
                               etherproto_string(htons(extracted_ethertype)));
                        }
                        if (!xflag && !qflag)
-                               default_print(p - layer2_len, caplen + layer2_len);
+                               default_print(p - hdr_len, caplen + hdr_len);
                }
                break;
 
-       case NLPID_Q933:
-               q933_print(p, length);
+       case NLPID_LMI:
+               lmi_print(p, length);
                break;
 
        default:
                if (!eflag)
-                       fr_hdr_print(p - layer2_len, length + layer2_len);
+                       fr_hdr_print(length + hdr_len,
+                                    dlci, flags, nlpid);
                if (!xflag)
                        default_print(p, caplen);
        }
 
-       if (xflag)
-               default_print(p, caplen);
-out:
-       putchar('\n');
+       return hdr_len;
 }
 
 /*
@@ -341,104 +340,148 @@ out:
 #define MSG_TYPE_STATUS           0x7D
 #define MSG_TYPE_STATUS_ENQ       0x75
 
-#define ONE_BYTE_IE_MASK 0xF0
+#define MSG_ANSI_LOCKING_SHIFT 0x95
+#define ONE_BYTE_IE_MASK       0xF0 /* details? */
 
-/* See L2 protocol ID picture above */
-struct q933_header {
-    u_char call_ref;  /* usually is 0 for framerelay PVC */
-    u_char msg_type;  
-};
+#define ANSI_REPORT_TYPE_IE    0x01
+#define ANSI_LINK_VERIFY_IE_91 0x19 /* details? */
+#define ANSI_LINK_VERIFY_IE    0x03
+#define ANSI_PVC_STATUS_IE     0x07
 
-#define REPORT_TYPE_IE    0x01
-#define LINK_VERIFY_IE_91 0x19
-#define LINK_VERIFY_IE_94 0x03
-#define PVC_STATUS_IE     0x07
-
-#define MAX_IE_SIZE
+#define CCITT_REPORT_TYPE_IE   0x51
+#define CCITT_LINK_VERIFY_IE   0x53
+#define CCITT_PVC_STATUS_IE    0x57
 
 struct common_ie_header {
-    u_char ie_id;
-    u_char ie_len;
+    u_int8_t ie_id;
+    u_int8_t ie_len;
 };
 
 #define FULL_STATUS 0
 #define LINK_VERIFY 1
 #define ASYNC_PVC   2
 
+
+/* Parses DLCI information element. */
+static const char * parse_dlci_ie(const u_char *p, u_int ie_len, char *buffer,
+                           size_t buffer_len)
+{
+       u_int dlci;
+
+       if ((ie_len < 3) ||
+           (p[0] & 0x80) ||
+           ((ie_len == 3) && !(p[1] & 0x80)) ||
+           ((ie_len == 4) && ((p[1] & 0x80) || !(p[2] & 0x80))) ||
+           ((ie_len == 5) && ((p[1] & 0x80) || (p[2] & 0x80) ||
+                              !(p[3] & 0x80))) ||
+           (ie_len > 5) ||
+           !(p[ie_len - 1] & 0x80))
+               return "Invalid DLCI IE";
+
+       dlci = ((p[0] & 0x3F) << 4) | ((p[1] & 0x78) >> 3);
+       if (ie_len == 4)
+               dlci = (dlci << 6) | ((p[2] & 0x7E) >> 1);
+       else if (ie_len == 5)
+               dlci = (dlci << 13) | (p[2] & 0x7F) | ((p[3] & 0x7E) >> 1);
+
+       snprintf(buffer, buffer_len, "DLCI %d: status %s%s", dlci,
+                p[ie_len - 1] & 0x8 ? "New, " : "",
+                p[ie_len - 1] & 0x2 ? "Active" : "Inactive");
+
+       return buffer;
+}
+
+
 static void
-q933_print(const u_char *p, int length)
+lmi_print(const u_char *p, u_int length)
 {
-       struct q933_header *header = (struct q933_header *)(p+1);
        const u_char *ptemp = p;
-       int ie_len;
        const char *decode_str;
        char temp_str[255];
        struct common_ie_header *ie_p;
+       int is_ansi = 0;
+
+       if (length < 9) {       /* shortest: Q.933a LINK VERIFY */
+               printf("[|lmi]");
+               return;
+       }
+
+       if (p[2] == MSG_ANSI_LOCKING_SHIFT)
+               is_ansi = 1;
     
        /* printing out header part */
-       printf("Call Ref: %02x, MSG Type: %02x", 
-              header->call_ref, header->msg_type);
-       switch(header->msg_type) {
+       printf(is_ansi ? "ANSI" : "CCITT");
+       if (p[0])
+               printf(" Call Ref: %02x!", p[0]);
+
+       switch(p[1]) {
+
        case MSG_TYPE_STATUS:
-           decode_str = "STATUS REPLY";
-           break;
+               printf(" STATUS REPLY\n");
+               break;
+
        case MSG_TYPE_STATUS_ENQ:
-           decode_str = "STATUS ENQUIRY";
-           break;
+               printf(" STATUS ENQUIRY\n");
+               break;
+
        default:
-           decode_str = "UNKNOWN MSG Type";
+               printf(" UNKNOWN MSG Type %02x\n", p[1]);
+               break;
        }
-       printf(" %s\n", decode_str);
 
-       length = length - 3;
-       ptemp = ptemp + 3;
+       if (length < (u_int)(2 - is_ansi)) {
+               printf("[|lmi]");
+               return;
+       }
+       length -= 2 - is_ansi;
+       ptemp += 2 + is_ansi;
        
        /* Loop through the rest of IE */
-       while( length > 0 ) {
-           if (ptemp[0] & ONE_BYTE_IE_MASK) {
-               ie_len = 1;
-               printf("\t\tOne byte IE: %02x, Content %02x\n", 
-                      (*ptemp & 0x70)>>4, (*ptemp & 0x0F));
-               length--;
-               ptemp++;
-           }
-           else {  /* Multi-byte IE */
+       while (length > 0) {
                ie_p = (struct common_ie_header *)ptemp;
-               switch (ie_p->ie_id) {
-               case REPORT_TYPE_IE:
-                   switch(ptemp[2]) {
-                   case FULL_STATUS:
-                       decode_str = "FULL STATUS";
-                       break;
-                   case LINK_VERIFY:
-                       decode_str = "LINK VERIFY";
-                       break;
-                   case ASYNC_PVC:
-                       decode_str = "Async PVC Status";
-                       break;
-                   default:
-                       decode_str = "Reserved Value";
-                   }
-                   break;
-               case LINK_VERIFY_IE_91:
-               case LINK_VERIFY_IE_94:
-                   snprintf(temp_str, sizeof (temp_str), "TX Seq: %3d, RX Seq: %3d",
-                           ptemp[2], ptemp[3]);
-                   decode_str = temp_str;
-                   break;
-               case PVC_STATUS_IE:
-                   snprintf(temp_str, sizeof (temp_str), "DLCI %d: status %s %s",
-                           ((ptemp[2]&0x3f)<<4)+ ((ptemp[3]&0x78)>>3), 
-                           ptemp[4] & 0x8 ?"new,":" ",
-                           ptemp[4] & 0x2 ?"Active":"Inactive");
-                   break;
-               default:
-                   decode_str = "Non-decoded Value";               
+               if (length < sizeof(struct common_ie_header) ||
+                   length < sizeof(struct common_ie_header) + ie_p->ie_len) {
+                       printf("[|lmi]");
+                       return;
                }
+
+               if ((is_ansi && ie_p->ie_id == ANSI_REPORT_TYPE_IE) ||
+                   (!is_ansi && ie_p->ie_id == CCITT_REPORT_TYPE_IE)) {
+                       switch(ptemp[2]) {
+
+                       case FULL_STATUS:
+                               decode_str = "FULL STATUS";
+                               break;
+
+                       case LINK_VERIFY:
+                               decode_str = "LINK VERIFY";
+                               break;
+
+                       case ASYNC_PVC:
+                               decode_str = "Async PVC Status";
+                               break;
+
+                       default:
+                               decode_str = "Reserved Value";
+                               break;
+                       }
+               } else if ((is_ansi && (ie_p->ie_id == ANSI_LINK_VERIFY_IE_91 ||
+                                       ie_p->ie_id == ANSI_LINK_VERIFY_IE)) ||
+                         (!is_ansi && ie_p->ie_id == CCITT_LINK_VERIFY_IE)) {
+                       snprintf(temp_str, sizeof(temp_str),
+                            "TX Seq: %3d, RX Seq: %3d",
+                            ptemp[2], ptemp[3]);
+                       decode_str = temp_str;
+               } else if ((is_ansi && ie_p->ie_id == ANSI_PVC_STATUS_IE) ||
+                          (!is_ansi && ie_p->ie_id == CCITT_PVC_STATUS_IE)) {
+                       decode_str = parse_dlci_ie(ptemp + 2, ie_p->ie_len,
+                                                  temp_str, sizeof(temp_str));
+               } else
+                       decode_str = "Non-decoded Value";                   
+
                printf("\t\tIE: %02X Len: %d, %s\n",
                       ie_p->ie_id, ie_p->ie_len, decode_str);
                length = length - ie_p->ie_len - 2;
                ptemp = ptemp + ie_p->ie_len + 2;
-           }
        }
 }