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 da26473f0320e8914c461cfd7d51064d3a89fe81..26499360cb293ef06eb4699ff6a3e46a39b9f4f2 100644 (file)
--- a/print-aodv.c
+++ b/print-aodv.c
@@ -184,22 +184,14 @@ static void
 aodv_extension(netdissect_options *ndo,
                const struct aodv_ext *ep, u_int length)
 {
-       u_int i;
        const struct aodv_hello *ah;
 
        switch (ep->type) {
        case AODV_EXT_HELLO:
-               if (ndo->ndo_snapend < (u_char *) ep) {
-                       ND_PRINT((ndo, " [|hello]"));
-                       return;
-               }
-               i = min(length, (u_int)(ndo->ndo_snapend - (u_char *)ep));
-               if (i < sizeof(struct aodv_hello)) {
-                       ND_PRINT((ndo, " [|hello]"));
-                       return;
-               }
-               i -= sizeof(struct aodv_hello);
-               ah = (void *)ep;
+               ah = (const struct aodv_hello *)(const void *)ep;
+               ND_TCHECK(*ah);
+               if (length < sizeof(struct aodv_hello))
+                       goto trunc;
                ND_PRINT((ndo, "\n\text HELLO %ld ms",
                    (unsigned long)EXTRACT_32BITS(&ah->interval)));
                break;
@@ -208,24 +200,21 @@ aodv_extension(netdissect_options *ndo,
                ND_PRINT((ndo, "\n\text %u %u", ep->type, ep->length));
                break;
        }
+       return;
+
+trunc:
+       ND_PRINT((ndo, " [|hello]"));
 }
 
 static void
-aodv_rreq(netdissect_options *ndo,
-          const struct aodv_rreq *ap, const u_char *dat, u_int length)
+aodv_rreq(netdissect_options *ndo, const u_char *dat, u_int length)
 {
        u_int i;
+       const struct aodv_rreq *ap = (const struct aodv_rreq *)dat;
 
-       if (ndo->ndo_snapend < dat) {
-               ND_PRINT((ndo, " [|aodv]"));
-               return;
-       }
-       i = min(length, (u_int)(ndo->ndo_snapend - dat));
-       if (i < sizeof(*ap)) {
-               ND_PRINT((ndo, " [|rreq]"));
-               return;
-       }
-       i -= sizeof(*ap);
+       ND_TCHECK(*ap);
+       if (length < sizeof(*ap))
+               goto trunc;
        ND_PRINT((ndo, " 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]" : "",
@@ -239,26 +228,24 @@ aodv_rreq(netdissect_options *ndo,
            (unsigned long)EXTRACT_32BITS(&ap->rreq_ds),
            ipaddr_string(ndo, &ap->rreq_oa),
            (unsigned long)EXTRACT_32BITS(&ap->rreq_os)));
+       i = length - sizeof(*ap);
        if (i >= sizeof(struct aodv_ext))
-               aodv_extension(ndo, (void *)(ap + 1), i);
+               aodv_extension(ndo, (const struct aodv_ext *)(dat + sizeof(*ap)), i);
+       return;
+
+trunc:
+       ND_PRINT((ndo, " [|rreq"));
 }
 
 static void
-aodv_rrep(netdissect_options *ndo,
-          const struct aodv_rrep *ap, const u_char *dat, u_int length)
+aodv_rrep(netdissect_options *ndo, const u_char *dat, u_int length)
 {
        u_int i;
+       const struct aodv_rrep *ap = (const struct aodv_rrep *)dat;
 
-       if (ndo->ndo_snapend < dat) {
-               ND_PRINT((ndo, " [|aodv]"));
-               return;
-       }
-       i = min(length, (u_int)(ndo->ndo_snapend - dat));
-       if (i < sizeof(*ap)) {
-               ND_PRINT((ndo, " [|rrep]"));
-               return;
-       }
-       i -= sizeof(*ap);
+       ND_TCHECK(*ap);
+       if (length < sizeof(*ap))
+               goto trunc;
        ND_PRINT((ndo, " rrep %u %s%sprefix %u hops %u\n"
            "\tdst %s dseq %lu src %s %lu ms", length,
            ap->rrep_type & RREP_REPAIR ? "[R]" : "",
@@ -269,62 +256,58 @@ aodv_rrep(netdissect_options *ndo,
            (unsigned long)EXTRACT_32BITS(&ap->rrep_ds),
            ipaddr_string(ndo, &ap->rrep_oa),
            (unsigned long)EXTRACT_32BITS(&ap->rrep_life)));
+       i = length - sizeof(*ap);
        if (i >= sizeof(struct aodv_ext))
-               aodv_extension(ndo, (void *)(ap + 1), i);
+               aodv_extension(ndo, (const struct aodv_ext *)(dat + sizeof(*ap)), i);
+       return;
+
+trunc:
+       ND_PRINT((ndo, " [|rreq"));
 }
 
 static void
-aodv_rerr(netdissect_options *ndo,
-          const struct aodv_rerr *ap, const u_char *dat, u_int length)
+aodv_rerr(netdissect_options *ndo, 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 (ndo->ndo_snapend < dat) {
-               ND_PRINT((ndo, " [|aodv]"));
-               return;
-       }
-       i = min(length, (u_int)(ndo->ndo_snapend - dat));
-       if (i < sizeof(*ap)) {
-               ND_PRINT((ndo, " [|rerr]"));
-               return;
-       }
-       i -= sizeof(*ap);
+       ND_TCHECK(*ap);
+       if (length < sizeof(*ap))
+               goto trunc;
        ND_PRINT((ndo, " 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)) {
+               ND_TCHECK(*dp);
                ND_PRINT((ndo, " {%s}(%ld)", ipaddr_string(ndo, &dp->u_da),
                    (unsigned long)EXTRACT_32BITS(&dp->u_ds)));
        }
        if ((i % sizeof(*dp)) != 0)
-               ND_PRINT((ndo, "[|rerr]"));
+               goto trunc;
+       return;
+
+trunc:
+       ND_PRINT((ndo, "[|rerr]"));
 }
 
 static void
 #ifdef INET6
-aodv_v6_rreq(netdissect_options *ndo,
-             const struct aodv_rreq6 *ap, const u_char *dat, u_int length)
+aodv_v6_rreq(netdissect_options *ndo, const u_char *dat, u_int length)
 #else
-aodv_v6_rreq(netdissect_options *ndo,
-             const struct aodv_rreq6 *ap _U_, const u_char *dat _U_, u_int length)
+aodv_v6_rreq(netdissect_options *ndo, 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 (ndo->ndo_snapend < dat) {
-               ND_PRINT((ndo, " [|aodv]"));
-               return;
-       }
-       i = min(length, (u_int)(ndo->ndo_snapend - dat));
-       if (i < sizeof(*ap)) {
-               ND_PRINT((ndo, " [|rreq6]"));
-               return;
-       }
-       i -= sizeof(*ap);
+       ND_TCHECK(*ap);
+       if (length < sizeof(*ap))
+               goto trunc;
        ND_PRINT((ndo, " 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]" : "",
@@ -338,8 +321,13 @@ aodv_v6_rreq(netdissect_options *ndo,
            (unsigned long)EXTRACT_32BITS(&ap->rreq_ds),
            ip6addr_string(ndo, &ap->rreq_oa),
            (unsigned long)EXTRACT_32BITS(&ap->rreq_os)));
+       i = length - sizeof(*ap);
        if (i >= sizeof(struct aodv_ext))
-               aodv_extension(ndo, (void *)(ap + 1), i);
+               aodv_extension(ndo, (const struct aodv_ext *)(dat + sizeof(*ap)), i);
+       return;
+
+trunc:
+       ND_PRINT((ndo, " [|rreq"));
 #else
        ND_PRINT((ndo, " v6 rreq %u", length));
 #endif
@@ -347,26 +335,18 @@ aodv_v6_rreq(netdissect_options *ndo,
 
 static void
 #ifdef INET6
-aodv_v6_rrep(netdissect_options *ndo,
-             const struct aodv_rrep6 *ap, const u_char *dat, u_int length)
+aodv_v6_rrep(netdissect_options *ndo, const u_char *dat, u_int length)
 #else
-aodv_v6_rrep(netdissect_options *ndo,
-             const struct aodv_rrep6 *ap _U_, const u_char *dat _U_, u_int length)
+aodv_v6_rrep(netdissect_options *ndo, 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 (ndo->ndo_snapend < dat) {
-               ND_PRINT((ndo, " [|aodv]"));
-               return;
-       }
-       i = min(length, (u_int)(ndo->ndo_snapend - dat));
-       if (i < sizeof(*ap)) {
-               ND_PRINT((ndo, " [|rrep6]"));
-               return;
-       }
-       i -= sizeof(*ap);
+       ND_TCHECK(*ap);
+       if (length < sizeof(*ap))
+               goto trunc;
        ND_PRINT((ndo, " rrep %u %s%sprefix %u hops %u\n"
           "\tdst %s dseq %lu src %s %lu ms", length,
            ap->rrep_type & RREP_REPAIR ? "[R]" : "",
@@ -377,8 +357,13 @@ aodv_v6_rrep(netdissect_options *ndo,
            (unsigned long)EXTRACT_32BITS(&ap->rrep_ds),
            ip6addr_string(ndo, &ap->rrep_oa),
            (unsigned long)EXTRACT_32BITS(&ap->rrep_life)));
+       i = length - sizeof(*ap);
        if (i >= sizeof(struct aodv_ext))
-               aodv_extension(ndo, (void *)(ap + 1), i);
+               aodv_extension(ndo, (const struct aodv_ext *)(dat + sizeof(*ap)), i);
+       return;
+
+trunc:
+       ND_PRINT((ndo, " [|rreq"));
 #else
        ND_PRINT((ndo, " rrep %u", length));
 #endif
@@ -386,38 +371,36 @@ aodv_v6_rrep(netdissect_options *ndo,
 
 static void
 #ifdef INET6
-aodv_v6_rerr(netdissect_options *ndo,
-             const struct aodv_rerr *ap, const u_char *dat, u_int length)
+aodv_v6_rerr(netdissect_options *ndo, const u_char *dat, u_int length)
 #else
-aodv_v6_rerr(netdissect_options *ndo,
-             const struct aodv_rerr *ap _U_, const u_char *dat, u_int length)
+aodv_v6_rerr(netdissect_options *ndo, 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 (ndo->ndo_snapend < dat) {
-               ND_PRINT((ndo, " [|aodv]"));
-               return;
-       }
-       i = min(length, (u_int)(ndo->ndo_snapend - dat));
-        if (i < sizeof(*ap)) {
-               ND_PRINT((ndo, " [|rerr]"));
-               return;
-       }
-       i -= sizeof(*ap);
+       ND_TCHECK(*ap);
+       if (length < sizeof(*ap))
+               goto trunc;
        ND_PRINT((ndo, " 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)) {
+               ND_TCHECK(*dp6);
                ND_PRINT((ndo, " {%s}(%ld)", ip6addr_string(ndo, &dp6->u_da),
                    (unsigned long)EXTRACT_32BITS(&dp6->u_ds)));
        }
        if ((i % sizeof(*dp6)) != 0)
-               ND_PRINT((ndo, "[|rerr]"));
+               goto trunc;
+       return;
+
+trunc:
+       ND_PRINT((ndo, "[|rerr]"));
 #else
        ND_PRINT((ndo, " rerr %u", length));
 #endif
@@ -425,26 +408,18 @@ aodv_v6_rerr(netdissect_options *ndo,
 
 static void
 #ifdef INET6
-aodv_v6_draft_01_rreq(netdissect_options *ndo,
-                      const struct aodv_rreq6_draft_01 *ap, const u_char *dat, u_int length)
+aodv_v6_draft_01_rreq(netdissect_options *ndo, const u_char *dat, u_int length)
 #else
-aodv_v6_draft_01_rreq(netdissect_options *ndo,
-                      const struct aodv_rreq6_draft_01 *ap _U_, const u_char *dat _U_, u_int length)
+aodv_v6_draft_01_rreq(netdissect_options *ndo, 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 (ndo->ndo_snapend < dat) {
-               ND_PRINT((ndo, " [|aodv]"));
-               return;
-       }
-       i = min(length, (u_int)(ndo->ndo_snapend - dat));
-       if (i < sizeof(*ap)) {
-               ND_PRINT((ndo, " [|rreq6]"));
-               return;
-       }
-       i -= sizeof(*ap);
+       ND_TCHECK(*ap);
+       if (length < sizeof(*ap))
+               goto trunc;
        ND_PRINT((ndo, " 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]" : "",
@@ -458,8 +433,13 @@ aodv_v6_draft_01_rreq(netdissect_options *ndo,
            (unsigned long)EXTRACT_32BITS(&ap->rreq_ds),
            ip6addr_string(ndo, &ap->rreq_oa),
            (unsigned long)EXTRACT_32BITS(&ap->rreq_os)));
+       i = length - sizeof(*ap);
        if (i >= sizeof(struct aodv_ext))
-               aodv_extension(ndo, (void *)(ap + 1), i);
+               aodv_extension(ndo, (const struct aodv_ext *)(dat + sizeof(*ap)), i);
+       return;
+
+trunc:
+       ND_PRINT((ndo, " [|rreq"));
 #else
        ND_PRINT((ndo, " rreq %u", length));
 #endif
@@ -467,26 +447,18 @@ aodv_v6_draft_01_rreq(netdissect_options *ndo,
 
 static void
 #ifdef INET6
-aodv_v6_draft_01_rrep(netdissect_options *ndo,
-                      const struct aodv_rrep6_draft_01 *ap, const u_char *dat, u_int length)
+aodv_v6_draft_01_rrep(netdissect_options *ndo, const u_char *dat, u_int length)
 #else
-aodv_v6_draft_01_rrep(netdissect_options *ndo,
-                      const struct aodv_rrep6_draft_01 *ap _U_, const u_char *dat _U_, u_int length)
+aodv_v6_draft_01_rrep(netdissect_options *ndo, 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 (ndo->ndo_snapend < dat) {
-               ND_PRINT((ndo, " [|aodv]"));
-               return;
-       }
-       i = min(length, (u_int)(ndo->ndo_snapend - dat));
-       if (i < sizeof(*ap)) {
-               ND_PRINT((ndo, " [|rrep6]"));
-               return;
-       }
-       i -= sizeof(*ap);
+       ND_TCHECK(*ap);
+       if (length < sizeof(*ap))
+               goto trunc;
        ND_PRINT((ndo, " rrep %u %s%sprefix %u hops %u\n"
           "\tdst %s dseq %lu src %s %lu ms", length,
            ap->rrep_type & RREP_REPAIR ? "[R]" : "",
@@ -497,8 +469,13 @@ aodv_v6_draft_01_rrep(netdissect_options *ndo,
            (unsigned long)EXTRACT_32BITS(&ap->rrep_ds),
            ip6addr_string(ndo, &ap->rrep_oa),
            (unsigned long)EXTRACT_32BITS(&ap->rrep_life)));
+       i = length - sizeof(*ap);
        if (i >= sizeof(struct aodv_ext))
-               aodv_extension(ndo, (void *)(ap + 1), i);
+               aodv_extension(ndo, (const struct aodv_ext *)(dat + sizeof(*ap)), i);
+       return;
+
+trunc:
+       ND_PRINT((ndo, " [|rreq"));
 #else
        ND_PRINT((ndo, " rrep %u", length));
 #endif
@@ -506,38 +483,36 @@ aodv_v6_draft_01_rrep(netdissect_options *ndo,
 
 static void
 #ifdef INET6
-aodv_v6_draft_01_rerr(netdissect_options *ndo,
-                      const struct aodv_rerr *ap, const u_char *dat, u_int length)
+aodv_v6_draft_01_rerr(netdissect_options *ndo, const u_char *dat, u_int length)
 #else
-aodv_v6_draft_01_rerr(netdissect_options *ndo,
-                      const struct aodv_rerr *ap _U_, const u_char *dat, u_int length)
+aodv_v6_draft_01_rerr(netdissect_options *ndo, 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 (ndo->ndo_snapend < dat) {
-               ND_PRINT((ndo, " [|aodv]"));
-               return;
-       }
-       i = min(length, (u_int)(ndo->ndo_snapend - dat));
-       if (i < sizeof(*ap)) {
-               ND_PRINT((ndo, " [|rerr]"));
-               return;
-       }
-       i -= sizeof(*ap);
+       ND_TCHECK(*ap);
+       if (length < sizeof(*ap))
+               goto trunc;
        ND_PRINT((ndo, " 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)) {
+               ND_TCHECK(*dp6);
                ND_PRINT((ndo, " {%s}(%ld)", ip6addr_string(ndo, &dp6->u_da),
                    (unsigned long)EXTRACT_32BITS(&dp6->u_ds)));
        }
        if ((i % sizeof(*dp6)) != 0)
-               ND_PRINT((ndo, "[|rerr]"));
+               goto trunc;
+       return;
+
+trunc:
+       ND_PRINT((ndo, "[|rerr]"));
 #else
        ND_PRINT((ndo, " rerr %u", length));
 #endif
@@ -561,23 +536,23 @@ aodv_print(netdissect_options *ndo,
 
        case AODV_RREQ:
                if (is_ip6)
-                       aodv_v6_rreq(ndo, (const struct aodv_rreq6 *)dat, dat, length);
+                       aodv_v6_rreq(ndo, dat, length);
                else
-                       aodv_rreq(ndo, (const struct aodv_rreq *)dat, dat, length);
+                       aodv_rreq(ndo, dat, length);
                break;
 
        case AODV_RREP:
                if (is_ip6)
-                       aodv_v6_rrep(ndo, (const struct aodv_rrep6 *)dat, dat, length);
+                       aodv_v6_rrep(ndo, dat, length);
                else
-                       aodv_rrep(ndo, (const struct aodv_rrep *)dat, dat, length);
+                       aodv_rrep(ndo, dat, length);
                break;
 
        case AODV_RERR:
                if (is_ip6)
-                       aodv_v6_rerr(ndo, (const struct aodv_rerr *)dat, dat, length);
+                       aodv_v6_rerr(ndo, dat, length);
                else
-                       aodv_rerr(ndo, (const struct aodv_rerr *)dat, dat, length);
+                       aodv_rerr(ndo, dat, length);
                break;
 
        case AODV_RREP_ACK:
@@ -585,15 +560,15 @@ aodv_print(netdissect_options *ndo,
                break;
 
        case AODV_V6_DRAFT_01_RREQ:
-               aodv_v6_draft_01_rreq(ndo, (const struct aodv_rreq6_draft_01 *)dat, dat, length);
+               aodv_v6_draft_01_rreq(ndo, dat, length);
                break;
 
        case AODV_V6_DRAFT_01_RREP:
-               aodv_v6_draft_01_rrep(ndo, (const struct aodv_rrep6_draft_01 *)dat, dat, length);
+               aodv_v6_draft_01_rrep(ndo, dat, length);
                break;
 
        case AODV_V6_DRAFT_01_RERR:
-               aodv_v6_draft_01_rerr(ndo, (const struct aodv_rerr *)dat, dat, length);
+               aodv_v6_draft_01_rerr(ndo, dat, length);
                break;
 
        case AODV_V6_DRAFT_01_RREP_ACK: