From: Guy Harris <gharris@sonic.net>
Date: Mon, 25 May 2020 09:02:34 +0000 (-0700)
Subject: Squelch some warnings.
X-Git-Tag: tcpdump-4.99-bp~389
X-Git-Url: https://git.tcpdump.org/tcpdump/commitdiff_plain/2ba1be35231dbdad50729e544fe4c2252aa15008

Squelch some warnings.

Use ND_BYTES_AVAILABLE_AFTER() to calculate the number of bytes
remaining in the packet after a given pointer, rather than doing the
subtraction directly; that casts the result to a u_int (we don't handle
packets bigger than the maximum u_int value, so the difference between
the pointers will never be bigger than that value), so we don't have to
deal with it being a 64-bit value on LP64 or LLP64 systems.  (It also
makes it a bit clearer what we're doing).

Clean up some indentation while we're at it.
---

diff --git a/print-ppp.c b/print-ppp.c
index 6156e195..dbd5283a 100644
--- a/print-ppp.c
+++ b/print-ppp.c
@@ -1413,7 +1413,7 @@ static void
 ppp_hdlc(netdissect_options *ndo,
          const u_char *p, u_int length)
 {
-	u_int caplen = ndo->ndo_snapend - p;
+	u_int caplen = ND_BYTES_AVAILABLE_AFTER(p);
 	u_char *b, *t, c;
 	const u_char *s;
 	u_int i, proto;
diff --git a/print-smb.c b/print-smb.c
index 402bb71f..38a6a433 100644
--- a/print-smb.c
+++ b/print-smb.c
@@ -952,7 +952,7 @@ nbt_tcp_print(netdissect_options *ndo,
 	goto trunc;
     if (ndo->ndo_snapend < data)
 	goto trunc;
-    caplen = ndo->ndo_snapend - data;
+    caplen = ND_BYTES_AVAILABLE_AFTER(data);
     if (caplen < 4)
 	goto trunc;
     maxbuf = data + caplen;
@@ -1269,7 +1269,7 @@ smb_tcp_print(netdissect_options *ndo,
 	goto trunc;
     if (ndo->ndo_snapend < data)
 	goto trunc;
-    caplen = ndo->ndo_snapend - data;
+    caplen = ND_BYTES_AVAILABLE_AFTER(data);
     if (caplen < 4)
 	goto trunc;
     maxbuf = data + caplen;
diff --git a/print-zeromq.c b/print-zeromq.c
index ac61056a..31d69968 100644
--- a/print-zeromq.c
+++ b/print-zeromq.c
@@ -169,13 +169,13 @@ static const u_char *
 zmtp1_print_intermediate_part(netdissect_options *ndo, const u_char *cp, const u_int len)
 {
 	u_int frame_offset;
-	uint64_t remaining_len;
+	u_int remaining_len;
 
 	ND_TCHECK_2(cp);
 	frame_offset = GET_BE_U_2(cp);
 	ND_PRINT("\n\t frame offset 0x%04x", frame_offset);
 	cp += 2;
-	remaining_len = ndo->ndo_snapend - cp; /* without the frame length */
+	remaining_len = ND_BYTES_AVAILABLE_AFTER(cp); /* without the frame length */
 
 	if (frame_offset == 0xFFFF)
 		frame_offset = len - 2; /* always within the declared length */
@@ -188,14 +188,14 @@ zmtp1_print_intermediate_part(netdissect_options *ndo, const u_char *cp, const u
 	if (frame_offset) {
 		ND_PRINT("\n\t frame intermediate part, %u bytes", frame_offset);
 		if (frame_offset > remaining_len)
-			ND_PRINT(" (%"PRIu64" captured)", remaining_len);
+			ND_PRINT(" (%u captured)", remaining_len);
 		if (ndo->ndo_vflag) {
-			uint64_t len_printed = min(frame_offset, remaining_len);
+			u_int len_printed = min(frame_offset, remaining_len);
 
 			if (ndo->ndo_vflag == 1)
 				len_printed = min(VBYTES, len_printed);
 			if (len_printed > 1) {
-				ND_PRINT(", first %"PRIu64" byte(s):", len_printed);
+				ND_PRINT(", first %u byte(s):", len_printed);
 				hex_and_ascii_print(ndo, "\n\t ", cp, len_printed);
 			}
 		}
diff --git a/util-print.c b/util-print.c
index 8806b475..c87e3265 100644
--- a/util-print.c
+++ b/util-print.c
@@ -475,19 +475,22 @@ void nd_print_invalid(netdissect_options *ndo)
 int
 print_unknown_data(netdissect_options *ndo, const u_char *cp,const char *ident,int len)
 {
+	u_int len_to_print;
+
 	if (len < 0) {
-          ND_PRINT("%sDissector error: print_unknown_data called with negative length",
+		ND_PRINT("%sDissector error: print_unknown_data called with negative length",
 		    ident);
 		return(0);
 	}
-	if (ndo->ndo_snapend - cp < len)
-		len = ndo->ndo_snapend - cp;
-	if (len < 0) {
-          ND_PRINT("%sDissector error: print_unknown_data called with pointer past end of packet",
+	len_to_print = len;
+	if (ndo->ndo_snapend < cp) {
+		ND_PRINT("%sDissector error: print_unknown_data called with pointer past end of packet",
 		    ident);
 		return(0);
 	}
-        hex_print(ndo, ident,cp,len);
+	if (ND_BYTES_AVAILABLE_AFTER(cp) < len_to_print)
+		len_to_print = ND_BYTES_AVAILABLE_AFTER(cp);
+	hex_print(ndo, ident, cp, len_to_print);
 	return(1); /* everything is ok */
 }