[v3,3/3] nvme-auth: always set valid seq_num in dhchap reply
Commit Message
Currently a seqnum of zero is sent during uni-directional
authentication. The zero value is reserved for the secure channel
feature which is not yet implemented.
Relevant extract from the spec:
The value 0h is used to indicate that bidirectional authentication
is not performed, but a challenge value C2 is carried in order to
generate a pre-shared key (PSK) for subsequent establishment of a
secure channel
Signed-off-by: Mark O'Donovan <shiftee@posteo.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
v1: used incorrect prefix nvme-tcp
v2: added spec extract to commit message
v3: read the seq-num in nvme-target code
drivers/nvme/host/auth.c | 3 +--
drivers/nvme/target/fabrics-cmd-auth.c | 2 +-
2 files changed, 2 insertions(+), 3 deletions(-)
Comments
On 10/25/23 12:51, Mark O'Donovan wrote:
> Currently a seqnum of zero is sent during uni-directional
> authentication. The zero value is reserved for the secure channel
> feature which is not yet implemented.
>
> Relevant extract from the spec:
> The value 0h is used to indicate that bidirectional authentication
> is not performed, but a challenge value C2 is carried in order to
> generate a pre-shared key (PSK) for subsequent establishment of a
> secure channel
>
> Signed-off-by: Mark O'Donovan <shiftee@posteo.net>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
>
> ---
> v1: used incorrect prefix nvme-tcp
> v2: added spec extract to commit message
> v3: read the seq-num in nvme-target code
>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cheers,
Hannes
@@ -316,15 +316,14 @@ static int nvme_auth_set_dhchap_reply_data(struct nvme_ctrl *ctrl,
chap->bi_directional = true;
get_random_bytes(chap->c2, chap->hash_len);
data->cvalid = 1;
- chap->s2 = nvme_auth_get_seqnum();
memcpy(data->rval + chap->hash_len, chap->c2,
chap->hash_len);
dev_dbg(ctrl->device, "%s: qid %d ctrl challenge %*ph\n",
__func__, chap->qid, (int)chap->hash_len, chap->c2);
} else {
memset(chap->c2, 0, chap->hash_len);
- chap->s2 = 0;
}
+ chap->s2 = nvme_auth_get_seqnum();
data->seqnum = cpu_to_le32(chap->s2);
if (chap->host_key_len) {
dev_dbg(ctrl->device, "%s: qid %d host public key %*ph\n",
@@ -163,11 +163,11 @@ static u16 nvmet_auth_reply(struct nvmet_req *req, void *d)
pr_debug("%s: ctrl %d qid %d challenge %*ph\n",
__func__, ctrl->cntlid, req->sq->qid, data->hl,
req->sq->dhchap_c2);
- req->sq->dhchap_s2 = le32_to_cpu(data->seqnum);
} else {
req->sq->authenticated = true;
req->sq->dhchap_c2 = NULL;
}
+ req->sq->dhchap_s2 = le32_to_cpu(data->seqnum);
return 0;
}