Bluetooth: Add basic LE SC OOB support for remote OOB data

This patch adds basic OOB pairing support when we've received the remote
OOB data. This includes tracking the remote r value (in smp->rr) as well
as doing the appropriate f4() call when needed. Previously the OOB rand
would have been stored in smp->rrnd however these are actually two
independent values so we need separate variables for them. Na/Nb in the
spec maps to smp->prnd/rrnd and ra/rb maps to smp->rr with smp->pr to
come once local OOB data is supported.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This commit is contained in:
Johan Hedberg 2014-10-28 15:17:05 +01:00 committed by Marcel Holtmann
parent 02b05bd8b0
commit a29b073351

View file

@ -71,6 +71,7 @@ struct smp_chan {
u8 rrnd[16]; /* SMP Pairing Random (remote) */
u8 pcnf[16]; /* SMP Pairing Confirm */
u8 tk[16]; /* SMP Temporary Key */
u8 rr[16];
u8 enc_key_size;
u8 remote_key_dist;
bdaddr_t id_addr;
@ -599,7 +600,7 @@ static void build_pairing_cmd(struct l2cap_conn *conn,
if (oob_data) {
set_bit(SMP_FLAG_OOB, &smp->flags);
oob_flag = SMP_OOB_PRESENT;
memcpy(smp->rrnd, oob_data->rand256, 16);
memcpy(smp->rr, oob_data->rand256, 16);
memcpy(smp->pcnf, oob_data->hash256, 16);
}
@ -1334,6 +1335,9 @@ static void sc_dhkey_check(struct smp_chan *smp)
if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
put_unaligned_le32(hcon->passkey_notify, r);
if (smp->method == REQ_OOB)
memcpy(r, smp->rr, 16);
smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap,
local_addr, remote_addr, check.e);
@ -1910,6 +1914,14 @@ static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
if (!test_bit(SMP_FLAG_SC, &smp->flags))
return smp_random(smp);
if (smp->method == REQ_OOB) {
if (!hcon->out)
smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
sizeof(smp->prnd), smp->prnd);
SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
goto mackey_and_ltk;
}
/* Passkey entry has special treatment */
if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
return sc_passkey_round(smp, SMP_CMD_PAIRING_RANDOM);
@ -1940,12 +1952,13 @@ static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
nb = smp->prnd;
}
mackey_and_ltk:
/* Generate MacKey and LTK */
err = sc_mackey_and_ltk(smp, smp->mackey, smp->tk);
if (err)
return SMP_UNSPECIFIED;
if (smp->method == JUST_WORKS) {
if (smp->method == JUST_WORKS || smp->method == REQ_OOB) {
if (hcon->out) {
sc_dhkey_check(smp);
SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
@ -2314,6 +2327,9 @@ static u8 sc_select_method(struct smp_chan *smp)
struct smp_cmd_pairing *local, *remote;
u8 local_mitm, remote_mitm, local_io, remote_io, method;
if (test_bit(SMP_FLAG_OOB, &smp->flags))
return REQ_OOB;
/* The preq/prsp contain the raw Pairing Request/Response PDUs
* which are needed as inputs to some crypto functions. To get
* the "struct smp_cmd_pairing" from them we need to skip the
@ -2412,6 +2428,24 @@ static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb)
return sc_passkey_round(smp, SMP_CMD_PUBLIC_KEY);
}
if (smp->method == REQ_OOB) {
err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->remote_pk,
smp->rr, 0, cfm.confirm_val);
if (err)
return SMP_UNSPECIFIED;
if (memcmp(cfm.confirm_val, smp->pcnf, 16))
return SMP_CONFIRM_FAILED;
if (hcon->out)
smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
sizeof(smp->prnd), smp->prnd);
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
return 0;
}
if (hcon->out)
SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);