auth-snmp: allow specifying management network prefix

So we don't go and try querying untrusted LLDP capable devices in
non-managed subnets.

1 files changed, 15 insertions, 7 deletions

diff --git a/src/blob.c b/src/blob.c
index ea02ea4..a6ccc62 100644
--- a/src/blob.c
+++ b/src/blob.c
@@ -139,23 +139,31 @@ int blob_icmp(blob_t a, blob_t b)
 	return strncasecmp(a.ptr, b.ptr, a.len);
 }
 
-unsigned long blob_inet_addr(blob_t b)
+int blob_pull_inet_addr(blob_t *b, struct in_addr *saddr)
 {
 	unsigned long ip = 0;
 	int i;
 
 	for (i = 0; i < 3; i++) {
-		ip += blob_pull_uint(&b, 10);
+		ip += blob_pull_uint(b, 10);
 		ip <<= 8;
-		if (!blob_pull_matching(&b, BLOB_STR(".")))
+		if (!blob_pull_matching(b, BLOB_STR(".")))
 			return 0;
 	}
-	ip += blob_pull_uint(&b, 10);
-	if (b.len != 0)
-		return 0;
-	return htonl(ip);
+	ip += blob_pull_uint(b, 10);
+	saddr->s_addr = htonl(ip);
+	return 1;
 }
 
+unsigned long blob_inet_addr(blob_t b)
+{
+	struct in_addr saddr;
+
+	if (blob_pull_inet_addr(&b, &saddr) && b.len == 0)
+		return saddr.s_addr;
+
+	return 0;
+}
 
 blob_t blob_pushed(blob_t buffer, blob_t left)
 {