resolv: Add internal __ns_name_length_uncompressed function

This function is useful for checking that the question name is
uncompressed (as it should be).

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/include/arpa/nameser.h b/include/arpa/nameser.h
index bb1dede187..6e4808f00d 100644
--- a/include/arpa/nameser.h
+++ b/include/arpa/nameser.h
@@ -95,5 +95,13 @@ libc_hidden_proto (__ns_name_unpack)
 extern __typeof (ns_samename) __libc_ns_samename;
 libc_hidden_proto (__libc_ns_samename)
 
+/* Packet parser helper functions.  */
+
+/* Verify that P points to an uncompressed domain name in wire format.
+   On success, return the length of the encoded name, including the
+   terminating null byte.  On failure, return -1 and set errno.  EOM
+   must point one past the last byte in the packet.  */
+int __ns_name_length_uncompressed (const unsigned char *p,
+				   const unsigned char *eom) attribute_hidden;
 # endif /* !_ISOMAC */
 #endif