Further cleanups.

Use ND_TCHECK() rather than home-brew bounds checks.  Do simpler length
checks.

Let i be the length of the actual remaining packet data; use ND_TCHECK()
inside loops that iterate over the remaining data.

Let the printers for particular message types cast the raw data pointer
to a pointer of the appropriate type, rather than passing two pointers,
with different types, to the same data.

diff --git a/print-aodv.c b/print-aodv.c
index 9763b44325e8b2a8547ef91661f725970cbb6a64..e0a1952fd7f5cae7ff9c28c33eb5fae63f1f680c 100644 (file)
--- a/print-aodv.c
+++ b/print-aodv.c
@@ -55,22 +55,14 @@ static const char rcsid[] _U_ =
 static void
 aodv_extension(const struct aodv_ext *ep, u_int length)
 {
-       u_int i;
        const struct aodv_hello *ah;
 
        switch (ep->type) {
        case AODV_EXT_HELLO:
-               if (snapend < (u_char *) ep) {
-                       printf(" [|hello]");
-                       return;
-               }
-               i = min(length, (u_int)(snapend - (u_char *)ep));
-               if (i < sizeof(struct aodv_hello)) {
-                       printf(" [|hello]");
-                       return;
-               }
-               i -= sizeof(struct aodv_hello);
-               ah = (void *)ep;
+               ah = (const struct aodv_hello *)(const void *)ep;
+               TCHECK(*ah);
+               if (length < sizeof(struct aodv_hello))
+                       goto trunc;
                printf("\n\text HELLO %ld ms",
                    (unsigned long)EXTRACT_32BITS(&ah->interval));
                break;
@@ -79,23 +71,21 @@ aodv_extension(const struct aodv_ext *ep, u_int length)
                printf("\n\text %u %u", ep->type, ep->length);
                break;
        }
+       return;
+
+trunc:
+       printf(" [|hello]");
 }
 
 static void
-aodv_rreq(const struct aodv_rreq *ap, const u_char *dat, u_int length)
+aodv_rreq(const u_char *dat, u_int length)
 {
        u_int i;
+       const struct aodv_rreq *ap = (const struct aodv_rreq *)dat;
 
-       if (snapend < dat) {
-               printf(" [|aodv]");
-               return;
-       }
-       i = min(length, (u_int)(snapend - dat));
-       if (i < sizeof(*ap)) {
-               printf(" [|rreq]");
-               return;
-       }
-       i -= sizeof(*ap);
+       TCHECK(*ap);
+       if (length < sizeof(*ap))
+               goto trunc;
        printf(" rreq %u %s%s%s%s%shops %u id 0x%08lx\n"
            "\tdst %s seq %lu src %s seq %lu", length,
            ap->rreq_type & RREQ_JOIN ? "[J]" : "",
@@ -109,25 +99,24 @@ aodv_rreq(const struct aodv_rreq *ap, const u_char *dat, u_int length)
            (unsigned long)EXTRACT_32BITS(&ap->rreq_ds),
            ipaddr_string(&ap->rreq_oa),
            (unsigned long)EXTRACT_32BITS(&ap->rreq_os));
+       i = length - sizeof(*ap);
        if (i >= sizeof(struct aodv_ext))
-               aodv_extension((void *)(ap + 1), i);
+               aodv_extension((const struct aodv_ext *)(dat + sizeof(*ap)), i);
+       return;
+
+trunc:
+       printf(" [|rreq");
 }
 
 static void
-aodv_rrep(const struct aodv_rrep *ap, const u_char *dat, u_int length)
+aodv_rrep(const u_char *dat, u_int length)
 {
        u_int i;
+       const struct aodv_rrep *ap = (const struct aodv_rrep *)dat;
 
-       if (snapend < dat) {
-               printf(" [|aodv]");
-               return;
-       }
-       i = min(length, (u_int)(snapend - dat));
-       if (i < sizeof(*ap)) {
-               printf(" [|rrep]");
-               return;
-       }
-       i -= sizeof(*ap);
+       TCHECK(*ap);
+       if (length < sizeof(*ap))
+               goto trunc;
        printf(" rrep %u %s%sprefix %u hops %u\n"
            "\tdst %s dseq %lu src %s %lu ms", length,
            ap->rrep_type & RREP_REPAIR ? "[R]" : "",
@@ -138,59 +127,58 @@ aodv_rrep(const struct aodv_rrep *ap, const u_char *dat, u_int length)
            (unsigned long)EXTRACT_32BITS(&ap->rrep_ds),
            ipaddr_string(&ap->rrep_oa),
            (unsigned long)EXTRACT_32BITS(&ap->rrep_life));
+       i = length - sizeof(*ap);
        if (i >= sizeof(struct aodv_ext))
-               aodv_extension((void *)(ap + 1), i);
+               aodv_extension((const struct aodv_ext *)(dat + sizeof(*ap)), i);
+       return;
+
+trunc:
+       printf(" [|rreq");
 }
 
 static void
-aodv_rerr(const struct aodv_rerr *ap, const u_char *dat, u_int length)
+aodv_rerr(const u_char *dat, u_int length)
 {
        u_int i, dc;
+       const struct aodv_rerr *ap = (const struct aodv_rerr *)dat;
        const struct rerr_unreach *dp;
 
-       if (snapend < dat) {
-               printf(" [|aodv]");
-               return;
-       }
-       i = min(length, (u_int)(snapend - dat));
-       if (i < sizeof(*ap)) {
-               printf(" [|rerr]");
-               return;
-       }
-       i -= sizeof(*ap);
+       TCHECK(*ap);
+       if (length < sizeof(*ap))
+               goto trunc;
        printf(" rerr %s [items %u] [%u]:",
            ap->rerr_flags & RERR_NODELETE ? "[D]" : "",
            ap->rerr_dc, length);
-       dp = (struct rerr_unreach *)(void *)(ap + 1);
+       dp = (struct rerr_unreach *)(dat + sizeof(*ap));
+       i = length - sizeof(*ap);
        for (dc = ap->rerr_dc; dc != 0 && i >= sizeof(*dp);
            ++dp, --dc, i -= sizeof(*dp)) {
+               TCHECK(*dp);
                printf(" {%s}(%ld)", ipaddr_string(&dp->u_da),
                    (unsigned long)EXTRACT_32BITS(&dp->u_ds));
        }
        if ((i % sizeof(*dp)) != 0)
-               printf("[|rerr]");
+               goto trunc;
+       return;
+
+trunc:
+       printf("[|rerr]");
 }
 
 static void
 #ifdef INET6
-aodv_v6_rreq(const struct aodv_rreq6 *ap, const u_char *dat, u_int length)
+aodv_v6_rreq(const u_char *dat, u_int length)
 #else
-aodv_v6_rreq(const struct aodv_rreq6 *ap _U_, const u_char *dat _U_, u_int length)
+aodv_v6_rreq(const u_char *dat _U_, u_int length)
 #endif
 {
 #ifdef INET6
        u_int i;
+       const struct aodv_rreq6 *ap = (const struct aodv_rreq6 *)dat;
 
-       if (snapend < dat) {
-               printf(" [|aodv]");
-               return;
-       }
-       i = min(length, (u_int)(snapend - dat));
-       if (i < sizeof(*ap)) {
-               printf(" [|rreq6]");
-               return;
-       }
-       i -= sizeof(*ap);
+       TCHECK(*ap);
+       if (length < sizeof(*ap))
+               goto trunc;
        printf(" v6 rreq %u %s%s%s%s%shops %u id 0x%08lx\n"
            "\tdst %s seq %lu src %s seq %lu", length,
            ap->rreq_type & RREQ_JOIN ? "[J]" : "",
@@ -204,8 +192,13 @@ aodv_v6_rreq(const struct aodv_rreq6 *ap _U_, const u_char *dat _U_, u_int lengt
            (unsigned long)EXTRACT_32BITS(&ap->rreq_ds),
            ip6addr_string(&ap->rreq_oa),
            (unsigned long)EXTRACT_32BITS(&ap->rreq_os));
+       i = length - sizeof(*ap);
        if (i >= sizeof(struct aodv_ext))
-               aodv_extension((void *)(ap + 1), i);
+               aodv_extension((const struct aodv_ext *)(dat + sizeof(*ap)), i);
+       return;
+
+trunc:
+       printf(" [|rreq");
 #else
        printf(" v6 rreq %u", length);
 #endif
@@ -213,24 +206,18 @@ aodv_v6_rreq(const struct aodv_rreq6 *ap _U_, const u_char *dat _U_, u_int lengt
 
 static void
 #ifdef INET6
-aodv_v6_rrep(const struct aodv_rrep6 *ap, const u_char *dat, u_int length)
+aodv_v6_rrep(const u_char *dat, u_int length)
 #else
-aodv_v6_rrep(const struct aodv_rrep6 *ap _U_, const u_char *dat _U_, u_int length)
+aodv_v6_rrep(const u_char *dat _U_, u_int length)
 #endif
 {
 #ifdef INET6
        u_int i;
+       const struct aodv_rrep6 *ap = (const struct aodv_rrep6 *)dat;
 
-       if (snapend < dat) {
-               printf(" [|aodv]");
-               return;
-       }
-       i = min(length, (u_int)(snapend - dat));
-       if (i < sizeof(*ap)) {
-               printf(" [|rrep6]");
-               return;
-       }
-       i -= sizeof(*ap);
+       TCHECK(*ap);
+       if (length < sizeof(*ap))
+               goto trunc;
        printf(" rrep %u %s%sprefix %u hops %u\n"
           "\tdst %s dseq %lu src %s %lu ms", length,
            ap->rrep_type & RREP_REPAIR ? "[R]" : "",
@@ -241,8 +228,13 @@ aodv_v6_rrep(const struct aodv_rrep6 *ap _U_, const u_char *dat _U_, u_int lengt
            (unsigned long)EXTRACT_32BITS(&ap->rrep_ds),
            ip6addr_string(&ap->rrep_oa),
            (unsigned long)EXTRACT_32BITS(&ap->rrep_life));
+       i = length - sizeof(*ap);
        if (i >= sizeof(struct aodv_ext))
-               aodv_extension((void *)(ap + 1), i);
+               aodv_extension((const struct aodv_ext *)(dat + sizeof(*ap)), i);
+       return;
+
+trunc:
+       printf(" [|rreq");
 #else
        printf(" rrep %u", length);
 #endif
@@ -250,36 +242,36 @@ aodv_v6_rrep(const struct aodv_rrep6 *ap _U_, const u_char *dat _U_, u_int lengt
 
 static void
 #ifdef INET6
-aodv_v6_rerr(const struct aodv_rerr *ap, const u_char *dat, u_int length)
+aodv_v6_rerr(const u_char *dat, u_int length)
 #else
-aodv_v6_rerr(const struct aodv_rerr *ap _U_, const u_char *dat, u_int length)
+aodv_v6_rerr(const u_char *dat _U_, u_int length)
 #endif
 {
 #ifdef INET6
        u_int i, dc;
+       const struct aodv_rerr *ap = (const struct aodv_rerr *)dat;
        const struct rerr_unreach6 *dp6;
 
-       if (snapend < dat) {
-               printf(" [|aodv]");
-               return;
-       }
-       i = min(length, (u_int)(snapend - dat));
-        if (i < sizeof(*ap)) {
-               printf(" [|rerr]");
-               return;
-       }
-       i -= sizeof(*ap);
+       TCHECK(*ap);
+       if (length < sizeof(*ap))
+               goto trunc;
        printf(" rerr %s [items %u] [%u]:",
            ap->rerr_flags & RERR_NODELETE ? "[D]" : "",
            ap->rerr_dc, length);
        dp6 = (struct rerr_unreach6 *)(void *)(ap + 1);
+       i = length - sizeof(*ap);
        for (dc = ap->rerr_dc; dc != 0 && i >= sizeof(*dp6);
            ++dp6, --dc, i -= sizeof(*dp6)) {
+               TCHECK(*dp6);
                printf(" {%s}(%ld)", ip6addr_string(&dp6->u_da),
                    (unsigned long)EXTRACT_32BITS(&dp6->u_ds));
        }
        if ((i % sizeof(*dp6)) != 0)
-               printf("[|rerr]");
+               goto trunc;
+       return;
+
+trunc:
+       printf("[|rerr]");
 #else
        printf(" rerr %u", length);
 #endif
@@ -287,24 +279,18 @@ aodv_v6_rerr(const struct aodv_rerr *ap _U_, const u_char *dat, u_int length)
 
 static void
 #ifdef INET6
-aodv_v6_draft_01_rreq(const struct aodv_rreq6_draft_01 *ap, const u_char *dat, u_int length)
+aodv_v6_draft_01_rreq(const u_char *dat, u_int length)
 #else
-aodv_v6_draft_01_rreq(const struct aodv_rreq6_draft_01 *ap _U_, const u_char *dat _U_, u_int length)
+aodv_v6_draft_01_rreq(const u_char *dat _U_, u_int length)
 #endif
 {
 #ifdef INET6
        u_int i;
+       const struct aodv_rreq6_draft_01 *ap = (const struct aodv_rreq6_draft_01 *)dat;
 
-       if (snapend < dat) {
-               printf(" [|aodv]");
-               return;
-       }
-       i = min(length, (u_int)(snapend - dat));
-       if (i < sizeof(*ap)) {
-               printf(" [|rreq6]");
-               return;
-       }
-       i -= sizeof(*ap);
+       TCHECK(*ap);
+       if (length < sizeof(*ap))
+               goto trunc;
        printf(" rreq %u %s%s%s%s%shops %u id 0x%08lx\n"
            "\tdst %s seq %lu src %s seq %lu", length,
            ap->rreq_type & RREQ_JOIN ? "[J]" : "",
@@ -318,8 +304,13 @@ aodv_v6_draft_01_rreq(const struct aodv_rreq6_draft_01 *ap _U_, const u_char *da
            (unsigned long)EXTRACT_32BITS(&ap->rreq_ds),
            ip6addr_string(&ap->rreq_oa),
            (unsigned long)EXTRACT_32BITS(&ap->rreq_os));
+       i = length - sizeof(*ap);
        if (i >= sizeof(struct aodv_ext))
-               aodv_extension((void *)(ap + 1), i);
+               aodv_extension((const struct aodv_ext *)(dat + sizeof(*ap)), i);
+       return;
+
+trunc:
+       printf(" [|rreq");
 #else
        printf(" rreq %u", length);
 #endif
@@ -327,24 +318,18 @@ aodv_v6_draft_01_rreq(const struct aodv_rreq6_draft_01 *ap _U_, const u_char *da
 
 static void
 #ifdef INET6
-aodv_v6_draft_01_rrep(const struct aodv_rrep6_draft_01 *ap, const u_char *dat, u_int length)
+aodv_v6_draft_01_rrep(const u_char *dat, u_int length)
 #else
-aodv_v6_draft_01_rrep(const struct aodv_rrep6_draft_01 *ap _U_, const u_char *dat _U_, u_int length)
+aodv_v6_draft_01_rrep(const u_char *dat _U_, u_int length)
 #endif
 {
 #ifdef INET6
        u_int i;
+       const struct aodv_rrep6_draft_01 *ap = (const struct aodv_rrep6_draft_01 *)dat;
 
-       if (snapend < dat) {
-               printf(" [|aodv]");
-               return;
-       }
-       i = min(length, (u_int)(snapend - dat));
-       if (i < sizeof(*ap)) {
-               printf(" [|rrep6]");
-               return;
-       }
-       i -= sizeof(*ap);
+       TCHECK(*ap);
+       if (length < sizeof(*ap))
+               goto trunc;
        printf(" rrep %u %s%sprefix %u hops %u\n"
           "\tdst %s dseq %lu src %s %lu ms", length,
            ap->rrep_type & RREP_REPAIR ? "[R]" : "",
@@ -355,8 +340,13 @@ aodv_v6_draft_01_rrep(const struct aodv_rrep6_draft_01 *ap _U_, const u_char *da
            (unsigned long)EXTRACT_32BITS(&ap->rrep_ds),
            ip6addr_string(&ap->rrep_oa),
            (unsigned long)EXTRACT_32BITS(&ap->rrep_life));
+       i = length - sizeof(*ap);
        if (i >= sizeof(struct aodv_ext))
-               aodv_extension((void *)(ap + 1), i);
+               aodv_extension((const struct aodv_ext *)(dat + sizeof(*ap)), i);
+       return;
+
+trunc:
+       printf(" [|rreq");
 #else
        printf(" rrep %u", length);
 #endif
@@ -364,36 +354,36 @@ aodv_v6_draft_01_rrep(const struct aodv_rrep6_draft_01 *ap _U_, const u_char *da
 
 static void
 #ifdef INET6
-aodv_v6_draft_01_rerr(const struct aodv_rerr *ap, const u_char *dat, u_int length)
+aodv_v6_draft_01_rerr(const u_char *dat, u_int length)
 #else
-aodv_v6_draft_01_rerr(const struct aodv_rerr *ap _U_, const u_char *dat, u_int length)
+aodv_v6_draft_01_rerr(const u_char *dat _U_, u_int length)
 #endif
 {
 #ifdef INET6
        u_int i, dc;
+       const struct aodv_rerr *ap = (const struct aodv_rerr *)dat;
        const struct rerr_unreach6_draft_01 *dp6;
 
-       if (snapend < dat) {
-               printf(" [|aodv]");
-               return;
-       }
-       i = min(length, (u_int)(snapend - dat));
-       if (i < sizeof(*ap)) {
-               printf(" [|rerr]");
-               return;
-       }
-       i -= sizeof(*ap);
+       TCHECK(*ap);
+       if (length < sizeof(*ap))
+               goto trunc;
        printf(" rerr %s [items %u] [%u]:",
            ap->rerr_flags & RERR_NODELETE ? "[D]" : "",
            ap->rerr_dc, length);
        dp6 = (struct rerr_unreach6_draft_01 *)(void *)(ap + 1);
+       i = length - sizeof(*ap);
        for (dc = ap->rerr_dc; dc != 0 && i >= sizeof(*dp6);
            ++dp6, --dc, i -= sizeof(*dp6)) {
+               TCHECK(*dp6);
                printf(" {%s}(%ld)", ip6addr_string(&dp6->u_da),
                    (unsigned long)EXTRACT_32BITS(&dp6->u_ds));
        }
        if ((i % sizeof(*dp6)) != 0)
-               printf("[|rerr]");
+               goto trunc;
+       return;
+
+trunc:
+       printf("[|rerr]");
 #else
        printf(" rerr %u", length);
 #endif
@@ -416,23 +406,23 @@ aodv_print(const u_char *dat, u_int length, int is_ip6)
 
        case AODV_RREQ:
                if (is_ip6)
-                       aodv_v6_rreq((const struct aodv_rreq6 *)dat, dat, length);
+                       aodv_v6_rreq(dat, length);
                else
-                       aodv_rreq((const struct aodv_rreq *)dat, dat, length);
+                       aodv_rreq(dat, length);
                break;
 
        case AODV_RREP:
                if (is_ip6)
-                       aodv_v6_rrep((const struct aodv_rrep6 *)dat, dat, length);
+                       aodv_v6_rrep(dat, length);
                else
-                       aodv_rrep((const struct aodv_rrep *)dat, dat, length);
+                       aodv_rrep(dat, length);
                break;
 
        case AODV_RERR:
                if (is_ip6)
-                       aodv_v6_rerr((const struct aodv_rerr *)dat, dat, length);
+                       aodv_v6_rerr(dat, length);
                else
-                       aodv_rerr((const struct aodv_rerr *)dat, dat, length);
+                       aodv_rerr(dat, length);
                break;
 
        case AODV_RREP_ACK:
@@ -440,15 +430,15 @@ aodv_print(const u_char *dat, u_int length, int is_ip6)
                break;
 
        case AODV_V6_DRAFT_01_RREQ:
-               aodv_v6_draft_01_rreq((const struct aodv_rreq6_draft_01 *)dat, dat, length);
+               aodv_v6_draft_01_rreq(dat, length);
                break;
 
        case AODV_V6_DRAFT_01_RREP:
-               aodv_v6_draft_01_rrep((const struct aodv_rrep6_draft_01 *)dat, dat, length);
+               aodv_v6_draft_01_rrep(dat, length);
                break;
 
        case AODV_V6_DRAFT_01_RERR:
-               aodv_v6_draft_01_rerr((const struct aodv_rerr *)dat, dat, length);
+               aodv_v6_draft_01_rerr(dat, length);
                break;
 
        case AODV_V6_DRAFT_01_RREP_ACK: