[SCTP]: Implement SCTP-AUTH initializations.

The patch initializes AUTH related members of the generic SCTP
structures and provides a way to enable/disable auth extension.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index 9bad8ba..ee4b212 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -74,6 +74,8 @@
 {
 	struct sctp_sock *sp;
 	int i;
+	sctp_paramhdr_t *p;
+	int err;
 
 	/* Retrieve the SCTP per socket area.  */
 	sp = sctp_sk((struct sock *)sk);
@@ -298,6 +300,30 @@
 	asoc->default_timetolive = sp->default_timetolive;
 	asoc->default_rcv_context = sp->default_rcv_context;
 
+	/* AUTH related initializations */
+	INIT_LIST_HEAD(&asoc->endpoint_shared_keys);
+	err = sctp_auth_asoc_copy_shkeys(ep, asoc, gfp);
+	if (err)
+		goto fail_init;
+
+	asoc->active_key_id = ep->active_key_id;
+	asoc->asoc_shared_key = NULL;
+
+	asoc->default_hmac_id = 0;
+	/* Save the hmacs and chunks list into this association */
+	if (ep->auth_hmacs_list)
+		memcpy(asoc->c.auth_hmacs, ep->auth_hmacs_list,
+			ntohs(ep->auth_hmacs_list->param_hdr.length));
+	if (ep->auth_chunk_list)
+		memcpy(asoc->c.auth_chunks, ep->auth_chunk_list,
+			ntohs(ep->auth_chunk_list->param_hdr.length));
+
+	/* Get the AUTH random number for this association */
+	p = (sctp_paramhdr_t *)asoc->c.auth_random;
+	p->type = SCTP_PARAM_RANDOM;
+	p->length = htons(sizeof(sctp_paramhdr_t) + SCTP_AUTH_RANDOM_LENGTH);
+	get_random_bytes(p+1, SCTP_AUTH_RANDOM_LENGTH);
+
 	return asoc;
 
 fail_init:
@@ -407,6 +433,12 @@
 	if (asoc->addip_last_asconf)
 		sctp_chunk_free(asoc->addip_last_asconf);
 
+	/* AUTH - Free the endpoint shared keys */
+	sctp_auth_destroy_keys(&asoc->endpoint_shared_keys);
+
+	/* AUTH - Free the association shared key */
+	sctp_auth_key_put(asoc->asoc_shared_key);
+
 	sctp_association_put(asoc);
 }
 
@@ -1112,6 +1144,8 @@
 			sctp_assoc_set_id(asoc, GFP_ATOMIC);
 		}
 	}
+
+	/* SCTP-AUTH: XXX something needs to be done here*/
 }
 
 /* Update the retran path for sending a retransmitted packet.