isisd: implement MD5 circuit authentication

* Replace command "isis passwd" with "isis passwd {clear|md5}"
* Verify HMAC MD5 on ISIS Hello PDUs
* Add HMAC MD5 authentication to md5.h/md5.c from RFC2104

1 files changed, 3 insertions, 0 deletions

diff --git a/lib/md5.h b/lib/md5.h
index 89b9a320..3ce83a63 100644
--- a/lib/md5.h
+++ b/lib/md5.h
@@ -82,4 +82,7 @@ do {				\
 	md5_result((x), (y));	\
 } while (0)
 
+/* From RFC 2104 */
+void hmac_md5(unsigned char* text, int text_len, unsigned char* key, int key_len, caddr_t digest);
+
 #endif /* ! _LIBZEBRA_MD5_H_*/