Don't directly fetch multi-byte integers from packets.

Use the EXTRACT_ macros to extract multi-byte integral values from
packets, rather than just dereferencing pointers into the packet; there
is no guarantee that the packet data will be aligned on the right
boundary, and there is no guarantee that, if they're not, a direct
access will work correctly.

diff --git a/print-ap1394.c b/print-ap1394.c
index dd9bc5a6c25dd131f4888bfb1289982c914c8dd7..fe07a6739640c5a2da6a6d88da5c4a7538c4c17c 100644 (file)
--- a/print-ap1394.c
+++ b/print-ap1394.c
@@ -33,6 +33,7 @@ static const char rcsid[] _U_ =
 #include <pcap.h>
 
 #include "interface.h"
+#include "extract.h"
 #include "addrtoname.h"
 #include "ethertype.h"
 
@@ -57,18 +58,21 @@ static inline void
 ap1394_hdr_print(register const u_char *bp, u_int length)
 {
        register const struct firewire_header *fp;
+       u_int16_t firewire_type;
+
        fp = (const struct firewire_header *)bp;
 
        (void)printf("%s > %s",
                     linkaddr_string(fp->firewire_dhost, LINKADDR_IEEE1394, FIREWIRE_EUI64_LEN),
                     linkaddr_string(fp->firewire_shost, LINKADDR_IEEE1394, FIREWIRE_EUI64_LEN));
 
+       firewire_type = EXTRACT_16BITS(&fp->firewire_type);
        if (!qflag) {
                (void)printf(", ethertype %s (0x%04x)",
-                              tok2str(ethertype_values,"Unknown", ntohs(fp->firewire_type)),
-                               ntohs(fp->firewire_type));            
+                              tok2str(ethertype_values,"Unknown", firewire_type),
+                               firewire_type);
         } else {
-                (void)printf(", %s", tok2str(ethertype_values,"Unknown Ethertype (0x%04x)", ntohs(fp->firewire_type)));  
+                (void)printf(", %s", tok2str(ethertype_values,"Unknown Ethertype (0x%04x)", firewire_type));
         }
 
        (void)printf(", length %u: ", length);
@@ -102,7 +106,7 @@ ap1394_if_print(const struct pcap_pkthdr *h, const u_char *p)
        fp = (struct firewire_header *)p;
        p += FIREWIRE_HDRLEN;
 
-       ether_type = ntohs(fp->firewire_type);
+       ether_type = EXTRACT_16BITS(&fp->firewire_type);
 
        extracted_ether_type = 0;
        if (ether_encap_print(ether_type, p, length, caplen,

diff --git a/print-arcnet.c b/print-arcnet.c
index 48a43030b4d22b5abb390056178c7f0089b8eab2..a7b9f0da6bd78d15411a9c686c9e9b83bbdb70f5 100644 (file)
--- a/print-arcnet.c
+++ b/print-arcnet.c
@@ -35,6 +35,7 @@ static const char rcsid[] _U_ =
 #include <pcap.h>
 
 #include "interface.h"
+#include "extract.h"
 #include "arcnet.h"
 
 static int arcnet_encap_print(u_char arctype, const u_char *p,
@@ -151,11 +152,11 @@ arcnet_if_print(const struct pcap_pkthdr *h, const u_char *p)
                                return (caplen);
                        }
                        flag = ap->arc_flag2;
-                       seqid = ntohs(ap->arc_seqid2);
+                       seqid = EXTRACT_16BITS(&ap->arc_seqid2);
                        archdrlen = ARC_HDRNEWLEN_EXC;
                } else {
                        flag = ap->arc_flag;
-                       seqid = ntohs(ap->arc_seqid);
+                       seqid = EXTRACT_16BITS(&ap->arc_seqid);
                        archdrlen = ARC_HDRNEWLEN;
                }
        }

diff --git a/print-bt.c b/print-bt.c
index 1f97475f85d3253a368e0790ea153741ce36fa19..259f3e5d9c76063b39bb3d5006050aca55274986 100644 (file)
--- a/print-bt.c
+++ b/print-bt.c
@@ -33,6 +33,7 @@ static const char rcsid[] _U_ =
 #include <string.h>
 
 #include "interface.h"
+#include "extract.h"
 #include "addrtoname.h"
 
 #if defined(DLT_BLUETOOTH_HCI_H4_WITH_PHDR) && defined(HAVE_PCAP_BLUETOOTH_H)
@@ -60,7 +61,7 @@ bt_if_print(const struct pcap_pkthdr *h, const u_char *p)
        length -= BT_HDRLEN;
        p += BT_HDRLEN;
        if (eflag)
-               (void)printf("hci length %d, direction %s, ", length, (ntohl(hdr->direction)&0x1)?"in":"out");
+               (void)printf("hci length %d, direction %s, ", length, (EXTRACT_32BITS(&hdr->direction)&0x1)?"in":"out");
 
        if (!suppress_default_print)
                default_print(p, caplen);

diff --git a/print-dccp.c b/print-dccp.c
index 2022fc8a491c1b4c816092486c65c4d69c8e7f56..fee4a6e50574f8d71eb69fe9eeff552a27cb4022 100644 (file)
--- a/print-dccp.c
+++ b/print-dccp.c
@@ -394,9 +394,6 @@ trunc2:
 static int dccp_print_option(const u_char *option)
 {      
        u_int8_t optlen, i;
-       u_int32_t *ts;
-       u_int16_t *var16;
-       u_int32_t *var32;
 
        TCHECK(*option);
 
@@ -470,22 +467,17 @@ static int dccp_print_option(const u_char *option)
                for (i = 0; i < optlen -2; i ++) printf("%02x", *(option +2 + i));      
                break;
        case 41:
-               ts = (u_int32_t *)(option + 2);
-               printf("timestamp %u", (u_int32_t)ntohl(*ts));
+               printf("timestamp %u", EXTRACT_32BITS(option + 2));
                break;
        case 42:
-               ts = (u_int32_t *)(option + 2);
-               printf("timestamp_echo %u", (u_int32_t)ntohl(*ts));
+               printf("timestamp_echo %u", EXTRACT_32BITS(option + 2));
                break;
        case 43:
                printf("elapsed_time ");
-               if (optlen == 6){
-                       ts = (u_int32_t *)(option + 2);
-                       printf("%u", (u_int32_t)ntohl(*ts));
-               } else {
-                       var16 = (u_int16_t *)(option + 2);
-                       printf("%u", ntohs(*var16));
-               }       
+               if (optlen == 6)
+                       printf("%u", EXTRACT_32BITS(option + 2));
+               else
+                       printf("%u", EXTRACT_16BITS(option + 2));
                break;
        case 44:
                printf("data_checksum ");
@@ -496,12 +488,10 @@ static int dccp_print_option(const u_char *option)
                        printf("CCID option %d",*option);
                        switch (optlen) {
                                case 4:
-                                       var16 = (u_int16_t *)(option + 2);
-                                       printf(" %u",ntohs(*var16));
+                                       printf(" %u", EXTRACT_16BITS(option + 2));
                                        break;
                                case 6:
-                                       var32 = (u_int32_t *)(option + 2);
-                                       printf(" %u",(u_int32_t)ntohl(*var32));
+                                       printf(" %u", EXTRACT_32BITS(option + 2));
                                        break;
                                default:
                                        break;

diff --git a/print-enc.c b/print-enc.c
index 0dc48fd70e7bf32a5f6577f4524fce9675c76a2c..e98f7f78215cc93d5310cbd9dd510df7fffaf352 100644 (file)
--- a/print-enc.c
+++ b/print-enc.c
@@ -35,6 +35,7 @@ static const char rcsid[] _U_ =
 #include <pcap.h>
 
 #include "interface.h"
+#include "extract.h"
 #include "addrtoname.h"
 
 #include "enc.h"
@@ -67,7 +68,7 @@ enc_if_print(const struct pcap_pkthdr *h, register const u_char *p)
        ENC_PRINT_TYPE(flags, M_AUTH, "authentic");
        ENC_PRINT_TYPE(flags, M_CONF, "confidential");
        /* ENC_PRINT_TYPE(flags, M_TUNNEL, "tunnel"); */
-       printf("SPI 0x%08x: ", (u_int32_t)ntohl(hdr->spi));
+       printf("SPI 0x%08x: ", EXTRACT_32BITS(&hdr->spi));
 
        length -= ENC_HDRLEN;
        caplen -= ENC_HDRLEN;

diff --git a/print-esp.c b/print-esp.c
index 80dd7218c5e7ce7b1d3456bb4658ad3604f420b3..ade654a33709454634ab44335aad1635d5591d4f 100644 (file)
--- a/print-esp.c
+++ b/print-esp.c
@@ -600,7 +600,7 @@ esp_print(netdissect_options *ndo,
                /* see if we can find the SA, and if so, decode it */
                for (sa = ndo->ndo_sa_list_head; sa != NULL; sa = sa->next) {
                        struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&sa->daddr;
-                       if (sa->spi == ntohl(esp->esp_spi) &&
+                       if (sa->spi == EXTRACT_32BITS(&esp->esp_spi) &&
                            sin6->sin6_family == AF_INET6 &&
                            memcmp(&sin6->sin6_addr, &ip6->ip6_dst,
                                   sizeof(struct in6_addr)) == 0) {
@@ -618,7 +618,7 @@ esp_print(netdissect_options *ndo,
                /* see if we can find the SA, and if so, decode it */
                for (sa = ndo->ndo_sa_list_head; sa != NULL; sa = sa->next) {
                        struct sockaddr_in *sin = (struct sockaddr_in *)&sa->daddr;
-                       if (sa->spi == ntohl(esp->esp_spi) &&
+                       if (sa->spi == EXTRACT_32BITS(&esp->esp_spi) &&
                            sin->sin_family == AF_INET &&
                            sin->sin_addr.s_addr == ip->ip_dst.s_addr) {
                                break;

diff --git a/print-ether.c b/print-ether.c
index 20a2a65fb868eff1acb5c563bd89c8629983062d..581d688207e8e47162ea550ad05af6067805553f 100644 (file)
--- a/print-ether.c
+++ b/print-ether.c
@@ -33,6 +33,7 @@ static const char rcsid[] _U_ =
 #include <pcap.h>
 
 #include "interface.h"
+#include "extract.h"
 #include "addrtoname.h"
 #include "ethertype.h"
 
@@ -86,24 +87,27 @@ static inline void
 ether_hdr_print(register const u_char *bp, u_int length)
 {
        register const struct ether_header *ep;
+       u_int16_t ether_type;
+
        ep = (const struct ether_header *)bp;
 
        (void)printf("%s > %s",
                     etheraddr_string(ESRC(ep)),
                     etheraddr_string(EDST(ep)));
 
+       ether_type = EXTRACT_16BITS(&ep->ether_type);
        if (!qflag) {
-               if (ntohs(ep->ether_type) <= ETHERMTU)
+               if (ether_type <= ETHERMTU)
                          (void)printf(", 802.3");
                 else 
                          (void)printf(", ethertype %s (0x%04x)",
-                                      tok2str(ethertype_values,"Unknown", ntohs(ep->ether_type)),
-                                       ntohs(ep->ether_type));       
+                                      tok2str(ethertype_values,"Unknown", ether_type),
+                                       ether_type);
         } else {
-                if (ntohs(ep->ether_type) <= ETHERMTU)
+                if (ether_type <= ETHERMTU)
                           (void)printf(", 802.3");
                 else 
-                          (void)printf(", %s", tok2str(ethertype_values,"Unknown Ethertype (0x%04x)", ntohs(ep->ether_type)));  
+                          (void)printf(", %s", tok2str(ethertype_values,"Unknown Ethertype (0x%04x)", ether_type));
         }
 
        (void)printf(", length %u: ", length);
@@ -129,7 +133,7 @@ ether_print(const u_char *p, u_int length, u_int caplen)
        ep = (struct ether_header *)p;
        p += ETHER_HDRLEN;
 
-       ether_type = ntohs(ep->ether_type);
+       ether_type = EXTRACT_16BITS(&ep->ether_type);
 
        /*
         * Is it (gag) an 802.3 encapsulation?
@@ -226,13 +230,16 @@ ether_encap_print(u_short ether_type, const u_char *p,
                return (1);
 
        case ETHERTYPE_8021Q:
-               if (eflag)
-                   printf("vlan %u, p %u%s, ",
-                          ntohs(*(u_int16_t *)p) & 0xfff,
-                          ntohs(*(u_int16_t *)p) >> 13,
-                          (ntohs(*(u_int16_t *)p) & 0x1000) ? ", CFI" : "");
+               if (eflag) {
+                       u_int16_t tag = EXTRACT_16BITS(p);
+
+                       printf("vlan %u, p %u%s, ",
+                           tag & 0xfff,
+                           tag >> 13,
+                           (tag & 0x1000) ? ", CFI" : "");
+               }
 
-               ether_type = ntohs(*(u_int16_t *)(p + 2));
+               ether_type = EXTRACT_16BITS(p + 2);
                p += 4;
                length -= 4;
                caplen -= 4;
@@ -259,7 +266,7 @@ ether_encap_print(u_short ether_type, const u_char *p,
                return (1);
 
         case ETHERTYPE_JUMBO:
-                ether_type = ntohs(*(u_int16_t *)(p));
+                ether_type = EXTRACT_16BITS(p);
                 p += 2;
                 length -= 2;      
                 caplen -= 2;

diff --git a/print-icmp6.c b/print-icmp6.c
index fb6ec3f9114ea8b8e6a8ca9adb229effeb0d77ca..cc486150e32cefea5253f6f68a5f0fa89c9ed1a1 100644 (file)
--- a/print-icmp6.c
+++ b/print-icmp6.c
@@ -853,7 +853,7 @@ mldv2_report_print(const u_char *bp, u_int len)
     }
 
     TCHECK(icp->icmp6_data16[1]);
-    ngroups = ntohs(icp->icmp6_data16[1]);
+    ngroups = EXTRACT_16BITS(&icp->icmp6_data16[1]);
     printf(", %d group record(s)", ngroups);
     if (vflag > 0) {
        /* Print the group records */
@@ -912,7 +912,7 @@ mldv2_query_print(const u_char *bp, u_int len)
        return;
     }
     TCHECK(icp->icmp6_data16[0]);
-    mrc = ntohs(icp->icmp6_data16[0]);
+    mrc = EXTRACT_16BITS(&icp->icmp6_data16[0]);
     if (mrc < 32768) {
        mrt = mrc;
     } else {
@@ -941,7 +941,7 @@ mldv2_query_print(const u_char *bp, u_int len)
     }
 
     TCHECK2(bp[26], 2);
-    nsrcs = ntohs(*(u_short *)&bp[26]);
+    nsrcs = EXTRACT_16BITS(&bp[26]);
     if (nsrcs > 0) {
        if (len < 28 + nsrcs * sizeof(struct in6_addr))
            printf(" [invalid number of sources]");

diff --git a/print-ospf.c b/print-ospf.c
index 4490496468ea57e43a53b115a78013802413978e..983c14f40e12d763dbf95d08ee439fb0b1556a7d 100644 (file)
--- a/print-ospf.c
+++ b/print-ospf.c
@@ -982,7 +982,7 @@ ospf_decode_v2(register const struct ospfhdr *op,
                        bittok2str(ospf_dd_flag_values,"none",op->ospf_db.db_flags));
                 TCHECK(op->ospf_db.db_ifmtu);
                 if (op->ospf_db.db_ifmtu) {
-                        printf(", MTU: %u", ntohs(op->ospf_db.db_ifmtu));
+                        printf(", MTU: %u", EXTRACT_16BITS(&op->ospf_db.db_ifmtu));
                 }
                 TCHECK(op->ospf_db.db_seq);
                 printf(", Sequence: 0x%08x", EXTRACT_32BITS(&op->ospf_db.db_seq));

diff --git a/print-pflog.c b/print-pflog.c
index 972cb4b1328c564d1210641763624e15f0e3f858..d1a461561ee204dc617a965272e2e97077c55570 100644 (file)
--- a/print-pflog.c
+++ b/print-pflog.c
@@ -94,8 +94,8 @@ pflog_print(const struct pfloghdr *hdr)
 {
        u_int32_t rulenr, subrulenr;
 
-       rulenr = ntohl(hdr->rulenr);
-       subrulenr = ntohl(hdr->subrulenr);
+       rulenr = EXTRACT_32BITS(&hdr->rulenr);
+       subrulenr = EXTRACT_32BITS(&hdr->subrulenr);
        if (subrulenr == (u_int32_t)-1)
                printf("rule %u/", rulenr);
        else

diff --git a/print-ppp.c b/print-ppp.c
index 708e934fd82906294427df3ba90ef967ab4674f6..7f231ead9cdcc52d046224ac2edfbf5de6acde6d 100644 (file)
--- a/print-ppp.c
+++ b/print-ppp.c
@@ -1629,7 +1629,7 @@ ppp_bsdos_if_print(const struct pcap_pkthdr *h _U_, register const u_char *p _U_
                hdrlength += 1;
        } else {
                /* Un-compressed protocol field */
-               ptype = ntohs(*(u_int16_t *)p);
+               ptype = EXTRACT_16BITS(p);
                if (eflag)
                        printf("%04x ", ptype);
                p += 2;
@@ -1649,7 +1649,7 @@ ppp_bsdos_if_print(const struct pcap_pkthdr *h _U_, register const u_char *p _U_
                 && ph->phdr_ctl == PPP_CONTROL) {
                        if (eflag)
                                printf("%02x %02x ", q[0], q[1]);
-                       ptype = ntohs(ph->phdr_type);
+                       ptype = EXTRACT_16BITS(&ph->phdr_type);
                        if (eflag && (ptype == PPP_VJC || ptype == PPP_VJNC)) {
                                printf("%s ", tok2str(ppptype2str,
                                                "proto-#%d", ptype));

diff --git a/print-sll.c b/print-sll.c
index 0057ca21805f53f9cdbd7906df57c17c4048d5a1..8edf3b0efa50fa0dda25e04aed532ec6419b03da 100644 (file)
--- a/print-sll.c
+++ b/print-sll.c
@@ -142,7 +142,7 @@ sll_if_print(const struct pcap_pkthdr *h, const u_char *p)
        caplen -= SLL_HDR_LEN;
        p += SLL_HDR_LEN;
 
-       ether_type = ntohs(sllp->sll_protocol);
+       ether_type = EXTRACT_16BITS(&sllp->sll_protocol);
 
        /*
         * Is it (gag) an 802.3 encapsulation, or some non-Ethernet

diff --git a/print-symantec.c b/print-symantec.c
index ebb62cd4d135ac5bb67644d8915484dfa69a4f72..e212b1a436b10f64b21f9322cd47640fddf6bf1c 100644 (file)
--- a/print-symantec.c
+++ b/print-symantec.c
@@ -33,6 +33,7 @@ static const char rcsid[] _U_ =
 #include <pcap.h>
 
 #include "interface.h"
+#include "extract.h"
 #include "addrtoname.h"
 #include "ethertype.h"
 
@@ -52,7 +53,7 @@ symantec_hdr_print(register const u_char *bp, u_int length)
 
        sp = (const struct symantec_header *)bp;
 
-       etype = ntohs(sp->ether_type);
+       etype = EXTRACT_16BITS(&sp->ether_type);
        if (!qflag) {
                if (etype <= ETHERMTU)
                          (void)printf("invalid ethertype %u", etype);
@@ -98,7 +99,7 @@ symantec_if_print(const struct pcap_pkthdr *h, const u_char *p)
        sp = (struct symantec_header *)p;
        p += sizeof (struct symantec_header);
 
-       ether_type = ntohs(sp->ether_type);
+       ether_type = EXTRACT_16BITS(&sp->ether_type);
 
        if (ether_type <= ETHERMTU) {
                /* ether_type not known, print raw packet */

diff --git a/print-tcp.c b/print-tcp.c
index ea57132221a76e754e23ed0f82a06063c82546d0..e2559ecf64ca0335eabd3db96303d0570c44942e 100644 (file)
--- a/print-tcp.c
+++ b/print-tcp.c
@@ -759,7 +759,7 @@ tcp_verify_signature(const struct ip *ip, const struct tcphdr *tp,
                 ip6 = (struct ip6_hdr *)ip;
                 MD5_Update(&ctx, (char *)&ip6->ip6_src, sizeof(ip6->ip6_src));
                 MD5_Update(&ctx, (char *)&ip6->ip6_dst, sizeof(ip6->ip6_dst));
-                len32 = htonl(ntohs(ip6->ip6_plen));
+                len32 = htonl(EXTRACT_16BITS(&ip6->ip6_plen));
                 MD5_Update(&ctx, (char *)&len32, sizeof(len32));
                 nxt = 0;
                 MD5_Update(&ctx, (char *)&nxt, sizeof(nxt));

diff --git a/print-token.c b/print-token.c
index 04defa9921b685e942762ba8f608c1602aaa597b..6a1b95da00d14b3ad85105471cf556599832785a 100644 (file)
--- a/print-token.c
+++ b/print-token.c
@@ -39,6 +39,7 @@ static const char rcsid[] _U_ =
 #include <string.h>
 
 #include "interface.h"
+#include "extract.h"
 #include "addrtoname.h"
 #include "ethertype.h"
 
@@ -135,10 +136,10 @@ token_print(const u_char *p, u_int length, u_int caplen)
                                printf(" [%d:%d]", RING_NUMBER(trp, seg),
                                    BRIDGE_NUMBER(trp, seg));
                } else {
-                       printf("rt = %x", ntohs(trp->token_rcf));
+                       printf("rt = %x", EXTRACT_16BITS(&trp->token_rcf));
 
                        for (seg = 0; seg < SEGMENT_COUNT(trp); seg++)
-                               printf(":%x", ntohs(trp->token_rseg[seg]));
+                               printf(":%x", EXTRACT_16BITS(&trp->token_rseg[seg]));
                }
                printf(" (%s) ", largest_frame[LARGEST_FRAME(trp)]);
        } else {