]> The Tcpdump Group git mirrors - tcpdump/blobdiff - print-ip.c
Use more the EXTRACT_8BITS() macro to fetch a one-byte value (17/n)
[tcpdump] / print-ip.c
index 362465e698defc7804718061be1acbb7d494c54e..519cd793d30464839c07f3d93dbf2be9a2c20153 100644 (file)
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  */
 
-#define NETDISSECT_REWORKED
+/* \summary: IP printer */
+
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
-#include <tcpdump-stdinc.h>
+#include <netdissect-stdinc.h>
 
 #include <string.h>
 
-#include "interface.h"
+#include "netdissect.h"
 #include "addrtoname.h"
-#include "extract.h"                   /* must come after interface.h */
+#include "extract.h"
 
 #include "ip.h"
 #include "ipproto.h"
@@ -53,7 +54,7 @@ static const struct tok ip_option_values[] = {
 /*
  * print the recorded route in an IP RR, LSRR or SSRR option.
  */
-static void
+static int
 ip_printroute(netdissect_options *ndo,
               register const u_char *cp, u_int length)
 {
@@ -62,19 +63,25 @@ ip_printroute(netdissect_options *ndo,
 
        if (length < 3) {
                ND_PRINT((ndo, " [bad length %u]", length));
-               return;
+               return (0);
        }
        if ((length + 1) & 3)
                ND_PRINT((ndo, " [bad length %u]", length));
+       ND_TCHECK(cp[2]);
        ptr = cp[2] - 1;
        if (ptr < 3 || ((ptr + 1) & 3) || ptr > length + 1)
                ND_PRINT((ndo, " [bad ptr %u]", cp[2]));
 
        for (len = 3; len < length; len += 4) {
+               ND_TCHECK2(cp[len], 4);
                ND_PRINT((ndo, " %s", ipaddr_string(ndo, &cp[len])));
                if (ptr > len)
                        ND_PRINT((ndo, ","));
        }
+       return (0);
+
+trunc:
+       return (-1);
 }
 
 /*
@@ -123,7 +130,7 @@ ip_finddst(netdissect_options *ndo,
                }
        }
 trunc:
-       UNALIGNED_MEMCPY(&retval, &ip->ip_dst.s_addr, sizeof(uint32_t));
+       UNALIGNED_MEMCPY(&retval, &ip->ip_dst, sizeof(uint32_t));
        return retval;
 }
 
@@ -148,9 +155,9 @@ nextproto4_cksum(netdissect_options *ndo,
        ph.len = htons((uint16_t)len);
        ph.mbz = 0;
        ph.proto = next_proto;
-       UNALIGNED_MEMCPY(&ph.src, &ip->ip_src.s_addr, sizeof(uint32_t));
+       UNALIGNED_MEMCPY(&ph.src, &ip->ip_src, sizeof(uint32_t));
        if (IP_HL(ip) == 5)
-               UNALIGNED_MEMCPY(&ph.dst, &ip->ip_dst.s_addr, sizeof(uint32_t));
+               UNALIGNED_MEMCPY(&ph.dst, &ip->ip_dst, sizeof(uint32_t));
        else
                ph.dst = ip_finddst(ndo, ip);
 
@@ -161,7 +168,7 @@ nextproto4_cksum(netdissect_options *ndo,
        return (in_cksum(vec, 2));
 }
 
-static void
+static int
 ip_printts(netdissect_options *ndo,
            register const u_char *cp, u_int length)
 {
@@ -172,16 +179,18 @@ ip_printts(netdissect_options *ndo,
 
        if (length < 4) {
                ND_PRINT((ndo, "[bad length %u]", length));
-               return;
+               return (0);
        }
        ND_PRINT((ndo, " TS{"));
        hoplen = ((cp[3]&0xF) != IPOPT_TS_TSONLY) ? 8 : 4;
        if ((length - 4) & (hoplen-1))
                ND_PRINT((ndo, "[bad length %u]", length));
+       ND_TCHECK(cp[2]);
        ptr = cp[2] - 1;
        len = 0;
        if (ptr < 4 || ((ptr - 4) & (hoplen-1)) || ptr > length + 1)
                ND_PRINT((ndo, "[bad ptr %u]", cp[2]));
+       ND_TCHECK(cp[3]);
        switch (cp[3]&0xF) {
        case IPOPT_TS_TSONLY:
                ND_PRINT((ndo, "TSONLY"));
@@ -210,8 +219,9 @@ ip_printts(netdissect_options *ndo,
        for (len = 4; len < length; len += hoplen) {
                if (ptr == len)
                        type = " ^ ";
-               ND_PRINT((ndo, "%s%d@%s", type, EXTRACT_32BITS(&cp[len+hoplen-4]),
-                      hoplen!=8 ? "" : ipaddr_string(ndo, &cp[len])));
+               ND_TCHECK2(cp[len], hoplen);
+               ND_PRINT((ndo, "%s%d@%s", type, EXTRACT_BE_32BITS(cp + len + hoplen - 4),
+                         hoplen!=8 ? "" : ipaddr_string(ndo, &cp[len])));
                type = " ";
        }
 
@@ -222,6 +232,10 @@ done:
                ND_PRINT((ndo, " [%d hops not recorded]} ", cp[3]>>4));
        else
                ND_PRINT((ndo, "}"));
+       return (0);
+
+trunc:
+       return (-1);
 }
 
 /*
@@ -271,13 +285,15 @@ ip_optprint(netdissect_options *ndo,
                        return;
 
                case IPOPT_TS:
-                       ip_printts(ndo, cp, option_len);
+                       if (ip_printts(ndo, cp, option_len) == -1)
+                               goto trunc;
                        break;
 
                case IPOPT_RR:       /* fall through */
                case IPOPT_SSRR:
                case IPOPT_LSRR:
-                       ip_printroute(ndo, cp, option_len);
+                       if (ip_printroute(ndo, cp, option_len) == -1)
+                               goto trunc;
                        break;
 
                case IPOPT_RA:
@@ -286,8 +302,8 @@ ip_optprint(netdissect_options *ndo,
                                break;
                        }
                        ND_TCHECK(cp[3]);
-                       if (EXTRACT_16BITS(&cp[2]) != 0)
-                               ND_PRINT((ndo, " value %u", EXTRACT_16BITS(&cp[2])));
+                       if (EXTRACT_BE_16BITS(cp + 2) != 0)
+                               ND_PRINT((ndo, " value %u", EXTRACT_BE_16BITS(cp + 2)));
                        break;
 
                case IPOPT_NOP:       /* nothing to print - fall through */
@@ -323,13 +339,16 @@ static void
 ip_print_demux(netdissect_options *ndo,
               struct ip_print_demux_state *ipds)
 {
-       struct protoent *proto;
-       struct cksum_vec vec[1];
+       const char *p_name;
 
 again:
        switch (ipds->nh) {
 
        case IPPROTO_AH:
+               if (!ND_TTEST(*ipds->cp)) {
+                       ND_PRINT((ndo, "[|AH]"));
+                       break;
+               }
                ipds->nh = *ipds->cp;
                ipds->advance = ah_print(ndo, ipds->cp);
                if (ipds->advance <= 0)
@@ -354,14 +373,14 @@ again:
 
        case IPPROTO_IPCOMP:
        {
-               int enh;
-               ipds->advance = ipcomp_print(ndo, ipds->cp, &enh);
-               if (ipds->advance <= 0)
-                       break;
-               ipds->cp += ipds->advance;
-               ipds->len -= ipds->advance;
-               ipds->nh = enh & 0xff;
-               goto again;
+               ipcomp_print(ndo, ipds->cp);
+               /*
+                * Either this has decompressed the payload and
+                * printed it, in which case there's nothing more
+                * to do, or it hasn't, in which case there's
+                * nothing more to do.
+                */
+               break;
        }
 
        case IPPROTO_SCTP:
@@ -436,12 +455,10 @@ again:
                }
                break;
 
-#ifdef INET6
        case IPPROTO_IPV6:
                /* ip6-in-ip encapsulation */
                ip6_print(ndo, ipds->cp, ipds->len);
                break;
-#endif /*INET6*/
 
        case IPPROTO_RSVP:
                rsvp_print(ndo, ipds->cp, ipds->len);
@@ -457,9 +474,7 @@ again:
                break;
 
        case IPPROTO_PIM:
-               vec[0].ptr = ipds->cp;
-               vec[0].len = ipds->len;
-               pim_print(ndo, ipds->cp, ipds->len, in_cksum(vec, 1));
+               pim_print(ndo, ipds->cp, ipds->len, (const u_char *)ipds->ip);
                break;
 
        case IPPROTO_VRRP:
@@ -484,8 +499,8 @@ again:
                break;
 
        default:
-               if (ndo->ndo_nflag==0 && (proto = getprotobynumber(ipds->nh)) != NULL)
-                       ND_PRINT((ndo, " %s", proto->p_name));
+               if (ndo->ndo_nflag==0 && (p_name = netdb_protoname(ipds->nh)) != NULL)
+                       ND_PRINT((ndo, " %s", p_name));
                else
                        ND_PRINT((ndo, " ip-proto-%d", ipds->nh));
                ND_PRINT((ndo, " %d", ipds->len));
@@ -526,21 +541,21 @@ ip_print(netdissect_options *ndo,
        u_int hlen;
        struct cksum_vec vec[1];
        uint16_t sum, ip_sum;
-       struct protoent *proto;
+       const char *p_name;
 
        ipds->ip = (const struct ip *)bp;
-       if (IP_V(ipds->ip) != 4) { /* print version if != 4 */
-           ND_PRINT((ndo, "IP%u ", IP_V(ipds->ip)));
+       ND_TCHECK(ipds->ip->ip_vhl);
+       if (IP_V(ipds->ip) != 4) { /* print version and fail if != 4 */
            if (IP_V(ipds->ip) == 6)
-             ND_PRINT((ndo, ", wrong link-layer encapsulation"));
+             ND_PRINT((ndo, "IP6, wrong link-layer encapsulation "));
+           else
+             ND_PRINT((ndo, "IP%u ", IP_V(ipds->ip)));
+           return;
        }
-       else if (!ndo->ndo_eflag)
+       if (!ndo->ndo_eflag)
                ND_PRINT((ndo, "IP "));
 
-       if ((u_char *)(ipds->ip + 1) > ndo->ndo_snapend) {
-               ND_PRINT((ndo, "%s", tstr));
-               return;
-       }
+       ND_TCHECK(*ipds->ip);
        if (length < sizeof (struct ip)) {
                ND_PRINT((ndo, "truncated-ip %u", length));
                return;
@@ -551,7 +566,7 @@ ip_print(netdissect_options *ndo,
                return;
        }
 
-       ipds->len = EXTRACT_16BITS(&ipds->ip->ip_len);
+       ipds->len = EXTRACT_BE_16BITS(&ipds->ip->ip_len);
        if (length < ipds->len)
                ND_PRINT((ndo, "truncated-ip - %u bytes missing! ",
                        ipds->len - length));
@@ -580,22 +595,27 @@ ip_print(netdissect_options *ndo,
 
        ipds->len -= hlen;
 
-       ipds->off = EXTRACT_16BITS(&ipds->ip->ip_off);
+       ipds->off = EXTRACT_BE_16BITS(&ipds->ip->ip_off);
 
         if (ndo->ndo_vflag) {
             ND_PRINT((ndo, "(tos 0x%x", (int)ipds->ip->ip_tos));
             /* ECN bits */
-            if (ipds->ip->ip_tos & 0x03) {
-                switch (ipds->ip->ip_tos & 0x03) {
-                case 1:
-                    ND_PRINT((ndo, ",ECT(1)"));
-                    break;
-                case 2:
-                    ND_PRINT((ndo, ",ECT(0)"));
-                    break;
-                case 3:
-                    ND_PRINT((ndo, ",CE"));
-                }
+            switch (ipds->ip->ip_tos & 0x03) {
+
+            case 0:
+                break;
+
+            case 1:
+                ND_PRINT((ndo, ",ECT(1)"));
+                break;
+
+            case 2:
+                ND_PRINT((ndo, ",ECT(0)"));
+                break;
+
+            case 3:
+                ND_PRINT((ndo, ",CE"));
+                break;
             }
 
             if (ipds->ip->ip_ttl >= 1)
@@ -608,26 +628,26 @@ ip_print(netdissect_options *ndo,
             */
 
            ND_PRINT((ndo, ", id %u, offset %u, flags [%s], proto %s (%u)",
-                         EXTRACT_16BITS(&ipds->ip->ip_id),
+                         EXTRACT_BE_16BITS(&ipds->ip->ip_id),
                          (ipds->off & 0x1fff) * 8,
                          bittok2str(ip_frag_values, "none", ipds->off&0xe000),
                          tok2str(ipproto_values,"unknown",ipds->ip->ip_p),
                          ipds->ip->ip_p));
 
-            ND_PRINT((ndo, ", length %u", EXTRACT_16BITS(&ipds->ip->ip_len)));
+            ND_PRINT((ndo, ", length %u", EXTRACT_BE_16BITS(&ipds->ip->ip_len)));
 
             if ((hlen - sizeof(struct ip)) > 0) {
                 ND_PRINT((ndo, ", options ("));
-                ip_optprint(ndo, (u_char *)(ipds->ip + 1), hlen - sizeof(struct ip));
+                ip_optprint(ndo, (const u_char *)(ipds->ip + 1), hlen - sizeof(struct ip));
                 ND_PRINT((ndo, ")"));
             }
 
-           if (!ndo->ndo_Kflag && (u_char *)ipds->ip + hlen <= ndo->ndo_snapend) {
-               vec[0].ptr = (const uint8_t *)(void *)ipds->ip;
+           if (!ndo->ndo_Kflag && (const u_char *)ipds->ip + hlen <= ndo->ndo_snapend) {
+               vec[0].ptr = (const uint8_t *)(const void *)ipds->ip;
                vec[0].len = hlen;
                sum = in_cksum(vec, 1);
                if (sum != 0) {
-                   ip_sum = EXTRACT_16BITS(&ipds->ip->ip_sum);
+                   ip_sum = EXTRACT_BE_16BITS(&ipds->ip->ip_sum);
                    ND_PRINT((ndo, ", bad cksum %x (->%x)!", ip_sum,
                             in_cksum_shouldbe(ip_sum, sum)));
                }
@@ -652,48 +672,57 @@ ip_print(netdissect_options *ndo,
                }
                ip_print_demux(ndo, ipds);
        } else {
-           /* Ultra quiet now means that all this stuff should be suppressed */
-           if (ndo->ndo_qflag > 1) return;
+               /*
+                * Ultra quiet now means that all this stuff should be
+                * suppressed.
+                */
+               if (ndo->ndo_qflag > 1)
+                       return;
 
-           /*
-            * if this isn't the first frag, we're missing the
-            * next level protocol header.  print the ip addr
-            * and the protocol.
-            */
-               if (ipds->off & 0x1fff) {
-                       ND_PRINT((ndo, "%s > %s:", ipaddr_string(ndo, &ipds->ip->ip_src),
-                                 ipaddr_string(ndo, &ipds->ip->ip_dst)));
-                       if (!ndo->ndo_nflag && (proto = getprotobynumber(ipds->ip->ip_p)) != NULL)
-                               ND_PRINT((ndo, " %s", proto->p_name));
-                       else
-                               ND_PRINT((ndo, " ip-proto-%d", ipds->ip->ip_p));
-               }
+               /*
+                * This isn't the first frag, so we're missing the
+                * next level protocol header.  print the ip addr
+                * and the protocol.
+                */
+               ND_PRINT((ndo, "%s > %s:", ipaddr_string(ndo, &ipds->ip->ip_src),
+                         ipaddr_string(ndo, &ipds->ip->ip_dst)));
+               if (!ndo->ndo_nflag && (p_name = netdb_protoname(ipds->ip->ip_p)) != NULL)
+                       ND_PRINT((ndo, " %s", p_name));
+               else
+                       ND_PRINT((ndo, " ip-proto-%d", ipds->ip->ip_p));
        }
+       return;
+
+trunc:
+       ND_PRINT((ndo, "%s", tstr));
+       return;
 }
 
 void
 ipN_print(netdissect_options *ndo, register const u_char *bp, register u_int length)
 {
-       struct ip hdr;
-
-       if (length < 4) {
+       if (length < 1) {
                ND_PRINT((ndo, "truncated-ip %d", length));
                return;
        }
-       memcpy (&hdr, bp, 4);
-       switch (IP_V(&hdr)) {
-       case 4:
+
+       ND_TCHECK(*bp);
+       switch (*bp & 0xF0) {
+       case 0x40:
                ip_print (ndo, bp, length);
-               return;
-#ifdef INET6
-       case 6:
+               break;
+       case 0x60:
                ip6_print (ndo, bp, length);
-               return;
-#endif
+               break;
        default:
-               ND_PRINT((ndo, "unknown ip %d", IP_V(&hdr)));
-               return;
+               ND_PRINT((ndo, "unknown ip %d", (*bp & 0xF0) >> 4));
+               break;
        }
+       return;
+
+trunc:
+       ND_PRINT((ndo, "%s", tstr));
+       return;
 }
 
 /*