sctp: add support for SCTP AUTH Information for sendmsg
This patch is to add support for SCTP AUTH Information for sendmsg,
as described in section 5.3.8 of RFC6458.
With this option, you can provide shared key identifier used for
sending the user message.
It's also a necessary send info for sctp_sendv.
Note that it reuses sinfo->sinfo_tsn to indicate if this option is
set and sinfo->sinfo_ssn to save the shkey ID which can be 0.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sctp/chunk.c b/net/sctp/chunk.c
index 9f28a9a..f889a84 100644
--- a/net/sctp/chunk.c
+++ b/net/sctp/chunk.c
@@ -206,7 +206,16 @@ struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *asoc,
max_data -= SCTP_PAD4(sizeof(struct sctp_auth_chunk) +
hmac_desc->hmac_len);
- shkey = asoc->shkey;
+ if (sinfo->sinfo_tsn &&
+ sinfo->sinfo_ssn != asoc->active_key_id) {
+ shkey = sctp_auth_get_shkey(asoc, sinfo->sinfo_ssn);
+ if (!shkey) {
+ err = -EINVAL;
+ goto errout;
+ }
+ } else {
+ shkey = asoc->shkey;
+ }
}
/* Check what's our max considering the above */
