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>
diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index 0c2214a..059a3da 100644
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -71,6 +71,7 @@
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 @@
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 @@
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 @@
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 @@
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 @@
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 @@
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);