From: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Date: Wed, 19 Feb 2025 02:44:34 +0000 (+1300)
Subject: ndr:dns: introduce and use MAX_COMP_LEN
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9032bb499194ef45ef80f131803bd7b163b781f0;p=thirdparty%2Fsamba.git

ndr:dns: introduce and use MAX_COMP_LEN

it means 63 or 0x3f, and is the maximum length of a DNS/NBT component.

We also simplify an error message that was fond of long hex
representations of small numbers.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=14378

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Andreas Schneider <asn@samba.org>
---

diff --git a/librpc/ndr/ndr_dns_utils.c b/librpc/ndr/ndr_dns_utils.c
index 9b603b364f1..68d7800173e 100644
--- a/librpc/ndr/ndr_dns_utils.c
+++ b/librpc/ndr/ndr_dns_utils.c
@@ -7,7 +7,7 @@
    plenty.
  */
 #define MAX_COMPONENTS 128
-
+#define MAX_COMP_LEN    63
 
 
 /*
@@ -87,7 +87,7 @@ static enum ndr_err_code ndr_pull_component(struct ndr_pull *ndr,
 					      err_name, (len &0xC));
 		}
 		if (*offset + len + 1 > ndr->data_size ||
-		    len > 63 /* impossible!, but we live in fear */ ) {
+		    len > MAX_COMP_LEN /* impossible!, but we live in fear */ ) {
 			return ndr_pull_error(ndr, NDR_ERR_STRING,
 					      "BAD %s NAME component, "\
 					      "length too long",
@@ -272,12 +272,11 @@ enum ndr_err_code ndr_push_dns_string_list(struct ndr_push *ndr,
 		complen = strcspn(s, ".");
 
 		/* the length must fit into 6 bits (i.e. <= 63) */
-		if (complen > 0x3F) {
+		if (complen > MAX_COMP_LEN) {
 			return ndr_push_error(ndr, NDR_ERR_STRING,
-					      "component length %zu[%08zX] > " \
-					      "0x0000003F",
+					      "component length %zu > %u",
 					      complen,
-					      complen);
+					      MAX_COMP_LEN);
 		}
 
 		if (complen == 0 && s[complen] == '.') {