-The chap_auth_hook is called to determine whether the response
-to a CHAP challenge provided by the peer is valid. user points to
-a null-terminated string containing the username supplied
-by the peer. remmd points to the response provided by the peer, of
-length remmd_len bytes. cstate is the internal CHAP state structure
-maintained by pppd. chap_auth_hook is expected to return one of
-CHAP_SUCCESS or CHAP_FAILURE.
+The chap_verify_hook is called to determine whether the peer's
+response to our CHAP challenge is valid -- it should return 1 if valid
+or 0 if not. The parameters are:
+
+* name points to a null-terminated string containing the username
+ supplied by the peer, or the remote name specified with the
+ "remotename" option.
+* ourname points to a null-terminated string containing the name of
+ the local machine (the hostname, or the name specified with the
+ "name" option).
+* id is the value of the id field from the challenge.
+* digest points to a chap_digest_type struct, which contains an
+ identifier for the type of digest in use plus function pointers for
+ functions for dealing with digests of that type.
+* challenge points to the challenge as a counted string (length byte
+ followed by the actual challenge bytes).
+* response points to the response as a counted string.
+* message points to an area of message_space bytes in which to store
+ any message that should be returned to the peer.