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-rw-r--r--net/bluetooth/smp.c1631
1 files changed, 1451 insertions, 180 deletions
diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index f09b6b65cf6b..6a46252fe66f 100644
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -29,14 +29,34 @@
#include <net/bluetooth/l2cap.h>
#include <net/bluetooth/mgmt.h>
+#include "ecc.h"
#include "smp.h"
+/* Low-level debug macros to be used for stuff that we don't want
+ * accidentially in dmesg, i.e. the values of the various crypto keys
+ * and the inputs & outputs of crypto functions.
+ */
+#ifdef DEBUG
+#define SMP_DBG(fmt, ...) printk(KERN_DEBUG "%s: " fmt, __func__, \
+ ##__VA_ARGS__)
+#else
+#define SMP_DBG(fmt, ...) no_printk(KERN_DEBUG "%s: " fmt, __func__, \
+ ##__VA_ARGS__)
+#endif
+
#define SMP_ALLOW_CMD(smp, code) set_bit(code, &smp->allow_cmd)
+/* Keys which are not distributed with Secure Connections */
+#define SMP_SC_NO_DIST (SMP_DIST_ENC_KEY | SMP_DIST_LINK_KEY);
+
#define SMP_TIMEOUT msecs_to_jiffies(30000)
-#define AUTH_REQ_MASK 0x07
-#define KEY_DIST_MASK 0x07
+#define AUTH_REQ_MASK(dev) (test_bit(HCI_SC_ENABLED, &(dev)->dev_flags) ? \
+ 0x1f : 0x07)
+#define KEY_DIST_MASK 0x07
+
+/* Maximum message length that can be passed to aes_cmac */
+#define CMAC_MSG_MAX 80
enum {
SMP_FLAG_TK_VALID,
@@ -44,6 +64,12 @@ enum {
SMP_FLAG_MITM_AUTH,
SMP_FLAG_COMPLETE,
SMP_FLAG_INITIATOR,
+ SMP_FLAG_SC,
+ SMP_FLAG_REMOTE_PK,
+ SMP_FLAG_DEBUG_KEY,
+ SMP_FLAG_WAIT_USER,
+ SMP_FLAG_DHKEY_PENDING,
+ SMP_FLAG_OOB,
};
struct smp_chan {
@@ -57,6 +83,7 @@ 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;
@@ -67,9 +94,43 @@ struct smp_chan {
struct smp_ltk *ltk;
struct smp_ltk *slave_ltk;
struct smp_irk *remote_irk;
+ u8 *link_key;
unsigned long flags;
+ u8 method;
+ u8 passkey_round;
+
+ /* Secure Connections variables */
+ u8 local_pk[64];
+ u8 local_sk[32];
+ u8 remote_pk[64];
+ u8 dhkey[32];
+ u8 mackey[16];
struct crypto_blkcipher *tfm_aes;
+ struct crypto_hash *tfm_cmac;
+};
+
+/* These debug key values are defined in the SMP section of the core
+ * specification. debug_pk is the public debug key and debug_sk the
+ * private debug key.
+ */
+static const u8 debug_pk[64] = {
+ 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
+ 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
+ 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
+ 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20,
+
+ 0x8b, 0xd2, 0x89, 0x15, 0xd0, 0x8e, 0x1c, 0x74,
+ 0x24, 0x30, 0xed, 0x8f, 0xc2, 0x45, 0x63, 0x76,
+ 0x5c, 0x15, 0x52, 0x5a, 0xbf, 0x9a, 0x32, 0x63,
+ 0x6d, 0xeb, 0x2a, 0x65, 0x49, 0x9c, 0x80, 0xdc,
+};
+
+static const u8 debug_sk[32] = {
+ 0xbd, 0x1a, 0x3c, 0xcd, 0xa6, 0xb8, 0x99, 0x58,
+ 0x99, 0xb7, 0x40, 0xeb, 0x7b, 0x60, 0xff, 0x4a,
+ 0x50, 0x3f, 0x10, 0xd2, 0xe3, 0xb3, 0xc9, 0x74,
+ 0x38, 0x5f, 0xc5, 0xa3, 0xd4, 0xf6, 0x49, 0x3f,
};
static inline void swap_buf(const u8 *src, u8 *dst, size_t len)
@@ -80,14 +141,22 @@ static inline void swap_buf(const u8 *src, u8 *dst, size_t len)
dst[len - 1 - i] = src[i];
}
-static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r)
+/* The following functions map to the LE SC SMP crypto functions
+ * AES-CMAC, f4, f5, f6, g2 and h6.
+ */
+
+static int aes_cmac(struct crypto_hash *tfm, const u8 k[16], const u8 *m,
+ size_t len, u8 mac[16])
{
- struct blkcipher_desc desc;
+ uint8_t tmp[16], mac_msb[16], msg_msb[CMAC_MSG_MAX];
+ struct hash_desc desc;
struct scatterlist sg;
- uint8_t tmp[16], data[16];
int err;
- if (tfm == NULL) {
+ if (len > CMAC_MSG_MAX)
+ return -EFBIG;
+
+ if (!tfm) {
BT_ERR("tfm %p", tfm);
return -EINVAL;
}
@@ -95,112 +164,237 @@ static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r)
desc.tfm = tfm;
desc.flags = 0;
- /* The most significant octet of key corresponds to k[0] */
+ crypto_hash_init(&desc);
+
+ /* Swap key and message from LSB to MSB */
swap_buf(k, tmp, 16);
+ swap_buf(m, msg_msb, len);
- err = crypto_blkcipher_setkey(tfm, tmp, 16);
+ SMP_DBG("msg (len %zu) %*phN", len, (int) len, m);
+ SMP_DBG("key %16phN", k);
+
+ err = crypto_hash_setkey(tfm, tmp, 16);
if (err) {
BT_ERR("cipher setkey failed: %d", err);
return err;
}
- /* Most significant octet of plaintextData corresponds to data[0] */
- swap_buf(r, data, 16);
+ sg_init_one(&sg, msg_msb, len);
- sg_init_one(&sg, data, 16);
+ err = crypto_hash_update(&desc, &sg, len);
+ if (err) {
+ BT_ERR("Hash update error %d", err);
+ return err;
+ }
- err = crypto_blkcipher_encrypt(&desc, &sg, &sg, 16);
+ err = crypto_hash_final(&desc, mac_msb);
+ if (err) {
+ BT_ERR("Hash final error %d", err);
+ return err;
+ }
+
+ swap_buf(mac_msb, mac, 16);
+
+ SMP_DBG("mac %16phN", mac);
+
+ return 0;
+}
+
+static int smp_f4(struct crypto_hash *tfm_cmac, const u8 u[32], const u8 v[32],
+ const u8 x[16], u8 z, u8 res[16])
+{
+ u8 m[65];
+ int err;
+
+ SMP_DBG("u %32phN", u);
+ SMP_DBG("v %32phN", v);
+ SMP_DBG("x %16phN z %02x", x, z);
+
+ m[0] = z;
+ memcpy(m + 1, v, 32);
+ memcpy(m + 33, u, 32);
+
+ err = aes_cmac(tfm_cmac, x, m, sizeof(m), res);
if (err)
- BT_ERR("Encrypt data error %d", err);
+ return err;
- /* Most significant octet of encryptedData corresponds to data[0] */
- swap_buf(data, r, 16);
+ SMP_DBG("res %16phN", res);
return err;
}
-static int smp_ah(struct crypto_blkcipher *tfm, u8 irk[16], u8 r[3], u8 res[3])
+static int smp_f5(struct crypto_hash *tfm_cmac, u8 w[32], u8 n1[16], u8 n2[16],
+ u8 a1[7], u8 a2[7], u8 mackey[16], u8 ltk[16])
{
- u8 _res[16];
+ /* The btle, salt and length "magic" values are as defined in
+ * the SMP section of the Bluetooth core specification. In ASCII
+ * the btle value ends up being 'btle'. The salt is just a
+ * random number whereas length is the value 256 in little
+ * endian format.
+ */
+ const u8 btle[4] = { 0x65, 0x6c, 0x74, 0x62 };
+ const u8 salt[16] = { 0xbe, 0x83, 0x60, 0x5a, 0xdb, 0x0b, 0x37, 0x60,
+ 0x38, 0xa5, 0xf5, 0xaa, 0x91, 0x83, 0x88, 0x6c };
+ const u8 length[2] = { 0x00, 0x01 };
+ u8 m[53], t[16];
int err;
- /* r' = padding || r */
- memcpy(_res, r, 3);
- memset(_res + 3, 0, 13);
+ SMP_DBG("w %32phN", w);
+ SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
+ SMP_DBG("a1 %7phN a2 %7phN", a1, a2);
- err = smp_e(tfm, irk, _res);
- if (err) {
- BT_ERR("Encrypt error");
+ err = aes_cmac(tfm_cmac, salt, w, 32, t);
+ if (err)
return err;
- }
- /* The output of the random address function ah is:
- * ah(h, r) = e(k, r') mod 2^24
- * The output of the security function e is then truncated to 24 bits
- * by taking the least significant 24 bits of the output of e as the
- * result of ah.
- */
- memcpy(res, _res, 3);
+ SMP_DBG("t %16phN", t);
+
+ memcpy(m, length, 2);
+ memcpy(m + 2, a2, 7);
+ memcpy(m + 9, a1, 7);
+ memcpy(m + 16, n2, 16);
+ memcpy(m + 32, n1, 16);
+ memcpy(m + 48, btle, 4);
+
+ m[52] = 0; /* Counter */
+
+ err = aes_cmac(tfm_cmac, t, m, sizeof(m), mackey);
+ if (err)
+ return err;
+
+ SMP_DBG("mackey %16phN", mackey);
+
+ m[52] = 1; /* Counter */
+
+ err = aes_cmac(tfm_cmac, t, m, sizeof(m), ltk);
+ if (err)
+ return err;
+
+ SMP_DBG("ltk %16phN", ltk);
return 0;
}
-bool smp_irk_matches(struct hci_dev *hdev, u8 irk[16], bdaddr_t *bdaddr)
+static int smp_f6(struct crypto_hash *tfm_cmac, const u8 w[16],
+ const u8 n1[16], u8 n2[16], const u8 r[16],
+ const u8 io_cap[3], const u8 a1[7], const u8 a2[7],
+ u8 res[16])
{
- struct l2cap_chan *chan = hdev->smp_data;
- struct crypto_blkcipher *tfm;
- u8 hash[3];
+ u8 m[65];
int err;
- if (!chan || !chan->data)
- return false;
+ SMP_DBG("w %16phN", w);
+ SMP_DBG("n1 %16phN n2 %16phN", n1, n2);
+ SMP_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN", r, io_cap, a1, a2);
- tfm = chan->data;
+ memcpy(m, a2, 7);
+ memcpy(m + 7, a1, 7);
+ memcpy(m + 14, io_cap, 3);
+ memcpy(m + 17, r, 16);
+ memcpy(m + 33, n2, 16);
+ memcpy(m + 49, n1, 16);
- BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk);
+ err = aes_cmac(tfm_cmac, w, m, sizeof(m), res);
+ if (err)
+ return err;
- err = smp_ah(tfm, irk, &bdaddr->b[3], hash);
+ BT_DBG("res %16phN", res);
+
+ return err;
+}
+
+static int smp_g2(struct crypto_hash *tfm_cmac, const u8 u[32], const u8 v[32],
+ const u8 x[16], const u8 y[16], u32 *val)
+{
+ u8 m[80], tmp[16];
+ int err;
+
+ SMP_DBG("u %32phN", u);
+ SMP_DBG("v %32phN", v);
+ SMP_DBG("x %16phN y %16phN", x, y);
+
+ memcpy(m, y, 16);
+ memcpy(m + 16, v, 32);
+ memcpy(m + 48, u, 32);
+
+ err = aes_cmac(tfm_cmac, x, m, sizeof(m), tmp);
if (err)
- return false;
+ return err;
- return !memcmp(bdaddr->b, hash, 3);
+ *val = get_unaligned_le32(tmp);
+ *val %= 1000000;
+
+ SMP_DBG("val %06u", *val);
+
+ return 0;
}
-int smp_generate_rpa(struct hci_dev *hdev, u8 irk[16], bdaddr_t *rpa)
+static int smp_h6(struct crypto_hash *tfm_cmac, const u8 w[16],
+ const u8 key_id[4], u8 res[16])
{
- struct l2cap_chan *chan = hdev->smp_data;
- struct crypto_blkcipher *tfm;
int err;
- if (!chan || !chan->data)
- return -EOPNOTSUPP;
+ SMP_DBG("w %16phN key_id %4phN", w, key_id);
- tfm = chan->data;
+ err = aes_cmac(tfm_cmac, w, key_id, 4, res);
+ if (err)
+ return err;
- get_random_bytes(&rpa->b[3], 3);
+ SMP_DBG("res %16phN", res);
- rpa->b[5] &= 0x3f; /* Clear two most significant bits */
- rpa->b[5] |= 0x40; /* Set second most significant bit */
+ return err;
+}
- err = smp_ah(tfm, irk, &rpa->b[3], rpa->b);
- if (err < 0)
+/* The following functions map to the legacy SMP crypto functions e, c1,
+ * s1 and ah.
+ */
+
+static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r)
+{
+ struct blkcipher_desc desc;
+ struct scatterlist sg;
+ uint8_t tmp[16], data[16];
+ int err;
+
+ if (!tfm) {
+ BT_ERR("tfm %p", tfm);
+ return -EINVAL;
+ }
+
+ desc.tfm = tfm;
+ desc.flags = 0;
+
+ /* The most significant octet of key corresponds to k[0] */
+ swap_buf(k, tmp, 16);
+
+ err = crypto_blkcipher_setkey(tfm, tmp, 16);
+ if (err) {
+ BT_ERR("cipher setkey failed: %d", err);
return err;
+ }
- BT_DBG("RPA %pMR", rpa);
+ /* Most significant octet of plaintextData corresponds to data[0] */
+ swap_buf(r, data, 16);
- return 0;
+ sg_init_one(&sg, data, 16);
+
+ err = crypto_blkcipher_encrypt(&desc, &sg, &sg, 16);
+ if (err)
+ BT_ERR("Encrypt data error %d", err);
+
+ /* Most significant octet of encryptedData corresponds to data[0] */
+ swap_buf(data, r, 16);
+
+ return err;
}
-static int smp_c1(struct smp_chan *smp, u8 k[16], u8 r[16], u8 preq[7],
- u8 pres[7], u8 _iat, bdaddr_t *ia, u8 _rat, bdaddr_t *ra,
- u8 res[16])
+static int smp_c1(struct crypto_blkcipher *tfm_aes, const u8 k[16],
+ const u8 r[16], const u8 preq[7], const u8 pres[7], u8 _iat,
+ const bdaddr_t *ia, u8 _rat, const bdaddr_t *ra, u8 res[16])
{
- struct hci_dev *hdev = smp->conn->hcon->hdev;
u8 p1[16], p2[16];
int err;
- BT_DBG("%s", hdev->name);
-
memset(p1, 0, 16);
/* p1 = pres || preq || _rat || _iat */
@@ -218,7 +412,7 @@ static int smp_c1(struct smp_chan *smp, u8 k[16], u8 r[16], u8 preq[7],
u128_xor((u128 *) res, (u128 *) r, (u128 *) p1);
/* res = e(k, res) */
- err = smp_e(smp->tfm_aes, k, res);
+ err = smp_e(tfm_aes, k, res);
if (err) {
BT_ERR("Encrypt data error");
return err;
@@ -228,32 +422,103 @@ static int smp_c1(struct smp_chan *smp, u8 k[16], u8 r[16], u8 preq[7],
u128_xor((u128 *) res, (u128 *) res, (u128 *) p2);
/* res = e(k, res) */
- err = smp_e(smp->tfm_aes, k, res);
+ err = smp_e(tfm_aes, k, res);
if (err)
BT_ERR("Encrypt data error");
return err;
}
-static int smp_s1(struct smp_chan *smp, u8 k[16], u8 r1[16], u8 r2[16],
- u8 _r[16])
+static int smp_s1(struct crypto_blkcipher *tfm_aes, const u8 k[16],
+ const u8 r1[16], const u8 r2[16], u8 _r[16])
{
- struct hci_dev *hdev = smp->conn->hcon->hdev;
int err;
- BT_DBG("%s", hdev->name);
-
/* Just least significant octets from r1 and r2 are considered */
memcpy(_r, r2, 8);
memcpy(_r + 8, r1, 8);
- err = smp_e(smp->tfm_aes, k, _r);
+ err = smp_e(tfm_aes, k, _r);
if (err)
BT_ERR("Encrypt data error");
return err;
}
+static int smp_ah(struct crypto_blkcipher *tfm, const u8 irk[16],
+ const u8 r[3], u8 res[3])
+{
+ u8 _res[16];
+ int err;
+
+ /* r' = padding || r */
+ memcpy(_res, r, 3);
+ memset(_res + 3, 0, 13);
+
+ err = smp_e(tfm, irk, _res);
+ if (err) {
+ BT_ERR("Encrypt error");
+ return err;
+ }
+
+ /* The output of the random address function ah is:
+ * ah(h, r) = e(k, r') mod 2^24
+ * The output of the security function e is then truncated to 24 bits
+ * by taking the least significant 24 bits of the output of e as the
+ * result of ah.
+ */
+ memcpy(res, _res, 3);
+
+ return 0;
+}
+
+bool smp_irk_matches(struct hci_dev *hdev, const u8 irk[16],
+ const bdaddr_t *bdaddr)
+{
+ struct l2cap_chan *chan = hdev->smp_data;
+ struct crypto_blkcipher *tfm;
+ u8 hash[3];
+ int err;
+
+ if (!chan || !chan->data)
+ return false;
+
+ tfm = chan->data;
+
+ BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk);
+
+ err = smp_ah(tfm, irk, &bdaddr->b[3], hash);
+ if (err)
+ return false;
+
+ return !memcmp(bdaddr->b, hash, 3);
+}
+
+int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16], bdaddr_t *rpa)
+{
+ struct l2cap_chan *chan = hdev->smp_data;
+ struct crypto_blkcipher *tfm;
+ int err;
+
+ if (!chan || !chan->data)
+ return -EOPNOTSUPP;
+
+ tfm = chan->data;
+
+ get_random_bytes(&rpa->b[3], 3);
+
+ rpa->b[5] &= 0x3f; /* Clear two most significant bits */
+ rpa->b[5] |= 0x40; /* Set second most significant bit */
+
+ err = smp_ah(tfm, irk, &rpa->b[3], rpa->b);
+ if (err < 0)
+ return err;
+
+ BT_DBG("RPA %pMR", rpa);
+
+ return 0;
+}
+
static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
{
struct l2cap_chan *chan = conn->smp;
@@ -274,8 +539,7 @@ static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
memset(&msg, 0, sizeof(msg));
- msg.msg_iov = (struct iovec *) &iv;
- msg.msg_iovlen = 2;
+ iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iv, 2, 1 + len);
l2cap_chan_send(chan, &msg, 1 + len);
@@ -288,17 +552,22 @@ static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT);
}
-static __u8 authreq_to_seclevel(__u8 authreq)
+static u8 authreq_to_seclevel(u8 authreq)
{
- if (authreq & SMP_AUTH_MITM)
- return BT_SECURITY_HIGH;
- else
+ if (authreq & SMP_AUTH_MITM) {
+ if (authreq & SMP_AUTH_SC)
+ return BT_SECURITY_FIPS;
+ else
+ return BT_SECURITY_HIGH;
+ } else {
return BT_SECURITY_MEDIUM;
+ }
}
static __u8 seclevel_to_authreq(__u8 sec_level)
{
switch (sec_level) {
+ case BT_SECURITY_FIPS:
case BT_SECURITY_HIGH:
return SMP_AUTH_MITM | SMP_AUTH_BONDING;
case BT_SECURITY_MEDIUM:
@@ -316,7 +585,7 @@ static void build_pairing_cmd(struct l2cap_conn *conn,
struct smp_chan *smp = chan->data;
struct hci_conn *hcon = conn->hcon;
struct hci_dev *hdev = hcon->hdev;
- u8 local_dist = 0, remote_dist = 0;
+ u8 local_dist = 0, remote_dist = 0, oob_flag = SMP_OOB_NOT_PRESENT;
if (test_bit(HCI_BONDABLE, &conn->hcon->hdev->dev_flags)) {
local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
@@ -332,24 +601,52 @@ static void build_pairing_cmd(struct l2cap_conn *conn,
if (test_bit(HCI_PRIVACY, &hdev->dev_flags))
local_dist |= SMP_DIST_ID_KEY;
+ if (test_bit(HCI_SC_ENABLED, &hdev->dev_flags) &&
+ (authreq & SMP_AUTH_SC)) {
+ struct oob_data *oob_data;
+ u8 bdaddr_type;
+
+ if (test_bit(HCI_SSP_ENABLED, &hdev->dev_flags)) {
+ local_dist |= SMP_DIST_LINK_KEY;
+ remote_dist |= SMP_DIST_LINK_KEY;
+ }
+
+ if (hcon->dst_type == ADDR_LE_DEV_PUBLIC)
+ bdaddr_type = BDADDR_LE_PUBLIC;
+ else
+ bdaddr_type = BDADDR_LE_RANDOM;
+
+ oob_data = hci_find_remote_oob_data(hdev, &hcon->dst,
+ bdaddr_type);
+ if (oob_data) {
+ set_bit(SMP_FLAG_OOB, &smp->flags);
+ oob_flag = SMP_OOB_PRESENT;
+ memcpy(smp->rr, oob_data->rand256, 16);
+ memcpy(smp->pcnf, oob_data->hash256, 16);
+ }
+
+ } else {
+ authreq &= ~SMP_AUTH_SC;
+ }
+
if (rsp == NULL) {
req->io_capability = conn->hcon->io_capability;
- req->oob_flag = SMP_OOB_NOT_PRESENT;
+ req->oob_flag = oob_flag;
req->max_key_size = SMP_MAX_ENC_KEY_SIZE;
req->init_key_dist = local_dist;
req->resp_key_dist = remote_dist;
- req->auth_req = (authreq & AUTH_REQ_MASK);
+ req->auth_req = (authreq & AUTH_REQ_MASK(hdev));
smp->remote_key_dist = remote_dist;
return;
}
rsp->io_capability = conn->hcon->io_capability;
- rsp->oob_flag = SMP_OOB_NOT_PRESENT;
+ rsp->oob_flag = oob_flag;
rsp->max_key_size = SMP_MAX_ENC_KEY_SIZE;
rsp->init_key_dist = req->init_key_dist & remote_dist;
rsp->resp_key_dist = req->resp_key_dist & local_dist;
- rsp->auth_req = (authreq & AUTH_REQ_MASK);
+ rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev));
smp->remote_key_dist = rsp->init_key_dist;
}
@@ -372,6 +669,7 @@ static void smp_chan_destroy(struct l2cap_conn *conn)
{
struct l2cap_chan *chan = conn->smp;
struct smp_chan *smp = chan->data;
+ struct hci_conn *hcon = conn->hcon;
bool complete;
BUG_ON(!smp);
@@ -379,34 +677,46 @@ static void smp_chan_destroy(struct l2cap_conn *conn)
cancel_delayed_work_sync(&smp->security_timer);
complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags);
- mgmt_smp_complete(conn->hcon, complete);
+ mgmt_smp_complete(hcon, complete);
kfree(smp->csrk);
kfree(smp->slave_csrk);
+ kfree(smp->link_key);
crypto_free_blkcipher(smp->tfm_aes);
+ crypto_free_hash(smp->tfm_cmac);
+
+ /* Ensure that we don't leave any debug key around if debug key
+ * support hasn't been explicitly enabled.
+ */
+ if (smp->ltk && smp->ltk->type == SMP_LTK_P256_DEBUG &&
+ !test_bit(HCI_KEEP_DEBUG_KEYS, &hcon->hdev->dev_flags)) {
+ list_del_rcu(&smp->ltk->list);
+ kfree_rcu(smp->ltk, rcu);
+ smp->ltk = NULL;
+ }
/* If pairing failed clean up any keys we might have */
if (!complete) {
if (smp->ltk) {
- list_del(&smp->ltk->list);
- kfree(smp->ltk);
+ list_del_rcu(&smp->ltk->list);
+ kfree_rcu(smp->ltk, rcu);
}
if (smp->slave_ltk) {
- list_del(&smp->slave_ltk->list);
- kfree(smp->slave_ltk);
+ list_del_rcu(&smp->slave_ltk->list);
+ kfree_rcu(smp->slave_ltk, rcu);
}
if (smp->remote_irk) {
- list_del(&smp->remote_irk->list);
- kfree(smp->remote_irk);
+ list_del_rcu(&smp->remote_irk->list);
+ kfree_rcu(smp->remote_irk, rcu);
}
}
chan->data = NULL;
kfree(smp);
- hci_conn_drop(conn->hcon);
+ hci_conn_drop(hcon);
}
static void smp_failure(struct l2cap_conn *conn, u8 reason)
@@ -430,6 +740,7 @@ static void smp_failure(struct l2cap_conn *conn, u8 reason)
#define REQ_PASSKEY 0x02
#define CFM_PASSKEY 0x03
#define REQ_OOB 0x04
+#define DSP_PASSKEY 0x05
#define OVERLAP 0xFF
static const u8 gen_method[5][5] = {
@@ -440,6 +751,14 @@ static const u8 gen_method[5][5] = {
{ CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP },
};
+static const u8 sc_method[5][5] = {
+ { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY },
+ { JUST_WORKS, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
+ { DSP_PASSKEY, DSP_PASSKEY, REQ_PASSKEY, JUST_WORKS, DSP_PASSKEY },
+ { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM },
+ { DSP_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY },
+};
+
static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io)
{
/* If either side has unknown io_caps, use JUST_CFM (which gets
@@ -449,6 +768,9 @@ static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io)
remote_io > SMP_IO_KEYBOARD_DISPLAY)
return JUST_CFM;
+ if (test_bit(SMP_FLAG_SC, &smp->flags))
+ return sc_method[remote_io][local_io];
+
return gen_method[remote_io][local_io];
}
@@ -458,7 +780,6 @@ static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
struct hci_conn *hcon = conn->hcon;
struct l2cap_chan *chan = conn->smp;
struct smp_chan *smp = chan->data;
- u8 method;
u32 passkey = 0;
int ret = 0;
@@ -475,26 +796,28 @@ static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
* table.
*/
if (!(auth & SMP_AUTH_MITM))
- method = JUST_CFM;
+ smp->method = JUST_CFM;
else
- method = get_auth_method(smp, local_io, remote_io);
+ smp->method = get_auth_method(smp, local_io, remote_io);
/* Don't confirm locally initiated pairing attempts */
- if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags))
- method = JUST_WORKS;
+ if (smp->method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR,
+ &smp->flags))
+ smp->method = JUST_WORKS;
/* Don't bother user space with no IO capabilities */
- if (method == JUST_CFM && hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
- method = JUST_WORKS;
+ if (smp->method == JUST_CFM &&
+ hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
+ smp->method = JUST_WORKS;
/* If Just Works, Continue with Zero TK */
- if (method == JUST_WORKS) {
+ if (smp->method == JUST_WORKS) {
set_bit(SMP_FLAG_TK_VALID, &smp->flags);
return 0;
}
/* Not Just Works/Confirm results in MITM Authentication */
- if (method != JUST_CFM) {
+ if (smp->method != JUST_CFM) {
set_bit(SMP_FLAG_MITM_AUTH, &smp->flags);
if (hcon->pending_sec_level < BT_SECURITY_HIGH)
hcon->pending_sec_level = BT_SECURITY_HIGH;
@@ -503,15 +826,15 @@ static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
/* If both devices have Keyoard-Display I/O, the master
* Confirms and the slave Enters the passkey.
*/
- if (method == OVERLAP) {
+ if (smp->method == OVERLAP) {
if (hcon->role == HCI_ROLE_MASTER)
- method = CFM_PASSKEY;
+ smp->method = CFM_PASSKEY;
else
- method = REQ_PASSKEY;
+ smp->method = REQ_PASSKEY;
}
/* Generate random passkey. */
- if (method == CFM_PASSKEY) {
+ if (smp->method == CFM_PASSKEY) {
memset(smp->tk, 0, sizeof(smp->tk));
get_random_bytes(&passkey, sizeof(passkey));
passkey %= 1000000;
@@ -520,12 +843,10 @@ static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
set_bit(SMP_FLAG_TK_VALID, &smp->flags);
}
- hci_dev_lock(hcon->hdev);
-
- if (method == REQ_PASSKEY)
+ if (smp->method == REQ_PASSKEY)
ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst,
hcon->type, hcon->dst_type);
- else if (method == JUST_CFM)
+ else if (smp->method == JUST_CFM)
ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst,
hcon->type, hcon->dst_type,
passkey, 1);
@@ -534,8 +855,6 @@ static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth,
hcon->type, hcon->dst_type,
passkey, 0);
- hci_dev_unlock(hcon->hdev);
-
return ret;
}
@@ -547,7 +866,7 @@ static u8 smp_confirm(struct smp_chan *smp)
BT_DBG("conn %p", conn);
- ret = smp_c1(smp, smp->tk, smp->prnd, smp->preq, smp->prsp,
+ ret = smp_c1(smp->tfm_aes, smp->tk, smp->prnd, smp->preq, smp->prsp,
conn->hcon->init_addr_type, &conn->hcon->init_addr,
conn->hcon->resp_addr_type, &conn->hcon->resp_addr,
cp.confirm_val);
@@ -578,7 +897,7 @@ static u8 smp_random(struct smp_chan *smp)
BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
- ret = smp_c1(smp, smp->tk, smp->rrnd, smp->preq, smp->prsp,
+ ret = smp_c1(smp->tfm_aes, smp->tk, smp->rrnd, smp->preq, smp->prsp,
hcon->init_addr_type, &hcon->init_addr,
hcon->resp_addr_type, &hcon->resp_addr, confirm);
if (ret)
@@ -594,7 +913,7 @@ static u8 smp_random(struct smp_chan *smp)
__le64 rand = 0;
__le16 ediv = 0;
- smp_s1(smp, smp->tk, smp->rrnd, smp->prnd, stk);
+ smp_s1(smp->tfm_aes, smp->tk, smp->rrnd, smp->prnd, stk);
memset(stk + smp->enc_key_size, 0,
SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size);
@@ -613,7 +932,7 @@ static u8 smp_random(struct smp_chan *smp)
smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
smp->prnd);
- smp_s1(smp, smp->tk, smp->prnd, smp->rrnd, stk);
+ smp_s1(smp->tfm_aes, smp->tk, smp->prnd, smp->rrnd, stk);
memset(stk + smp->enc_key_size, 0,
SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size);
@@ -648,11 +967,13 @@ static void smp_notify_keys(struct l2cap_conn *conn)
mgmt_new_irk(hdev, smp->remote_irk);
/* Now that user space can be considered to know the
* identity address track the connection based on it
- * from now on.
+ * from now on (assuming this is an LE link).
*/
- bacpy(&hcon->dst, &smp->remote_irk->bdaddr);
- hcon->dst_type = smp->remote_irk->addr_type;
- queue_work(hdev->workqueue, &conn->id_addr_update_work);
+ if (hcon->type == LE_LINK) {
+ bacpy(&hcon->dst, &smp->remote_irk->bdaddr);
+ hcon->dst_type = smp->remote_irk->addr_type;
+ queue_work(hdev->workqueue, &conn->id_addr_update_work);
+ }
/* When receiving an indentity resolving key for
* a remote device that does not use a resolvable
@@ -665,16 +986,26 @@ static void smp_notify_keys(struct l2cap_conn *conn)
* just remove it.
*/
if (!bacmp(&smp->remote_irk->rpa, BDADDR_ANY)) {
- list_del(&smp->remote_irk->list);
- kfree(smp->remote_irk);
+ list_del_rcu(&smp->remote_irk->list);
+ kfree_rcu(smp->remote_irk, rcu);
smp->remote_irk = NULL;
}
}
- /* The LTKs and CSRKs should be persistent only if both sides
- * had the bonding bit set in their authentication requests.
- */
- persistent = !!((req->auth_req & rsp->auth_req) & SMP_AUTH_BONDING);
+ if (hcon->type == ACL_LINK) {
+ if (hcon->key_type == HCI_LK_DEBUG_COMBINATION)
+ persistent = false;
+ else
+ persistent = !test_bit(HCI_CONN_FLUSH_KEY,
+ &hcon->flags);
+ } else {
+ /* The LTKs and CSRKs should be persistent only if both sides
+ * had the bonding bit set in their authentication requests.
+ */
+ persistent = !!((req->auth_req & rsp->auth_req) &
+ SMP_AUTH_BONDING);
+ }
+
if (smp->csrk) {
smp->csrk->bdaddr_type = hcon->dst_type;
@@ -699,6 +1030,81 @@ static void smp_notify_keys(struct l2cap_conn *conn)
bacpy(&smp->slave_ltk->bdaddr, &hcon->dst);
mgmt_new_ltk(hdev, smp->slave_ltk, persistent);
}
+
+ if (smp->link_key) {
+ struct link_key *key;
+ u8 type;
+
+ if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
+ type = HCI_LK_DEBUG_COMBINATION;
+ else if (hcon->sec_level == BT_SECURITY_FIPS)
+ type = HCI_LK_AUTH_COMBINATION_P256;
+ else
+ type = HCI_LK_UNAUTH_COMBINATION_P256;
+
+ key = hci_add_link_key(hdev, smp->conn->hcon, &hcon->dst,
+ smp->link_key, type, 0, &persistent);
+ if (key) {
+ mgmt_new_link_key(hdev, key, persistent);
+
+ /* Don't keep debug keys around if the relevant
+ * flag is not set.
+ */
+ if (!test_bit(HCI_KEEP_DEBUG_KEYS, &hdev->dev_flags) &&
+ key->type == HCI_LK_DEBUG_COMBINATION) {
+ list_del_rcu(&key->list);
+ kfree_rcu(key, rcu);
+ }
+ }
+ }
+}
+
+static void sc_add_ltk(struct smp_chan *smp)
+{
+ struct hci_conn *hcon = smp->conn->hcon;
+ u8 key_type, auth;
+
+ if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags))
+ key_type = SMP_LTK_P256_DEBUG;
+ else
+ key_type = SMP_LTK_P256;
+
+ if (hcon->pending_sec_level == BT_SECURITY_FIPS)
+ auth = 1;
+ else
+ auth = 0;
+
+ memset(smp->tk + smp->enc_key_size, 0,
+ SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size);
+
+ smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
+ key_type, auth, smp->tk, smp->enc_key_size,
+ 0, 0);
+}
+
+static void sc_generate_link_key(struct smp_chan *smp)
+{
+ /* These constants are as specified in the core specification.
+ * In ASCII they spell out to 'tmp1' and 'lebr'.
+ */
+ const u8 tmp1[4] = { 0x31, 0x70, 0x6d, 0x74 };
+ const u8 lebr[4] = { 0x72, 0x62, 0x65, 0x6c };
+
+ smp->link_key = kzalloc(16, GFP_KERNEL);
+ if (!smp->link_key)
+ return;
+
+ if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) {
+ kfree(smp->link_key);
+ smp->link_key = NULL;
+ return;
+ }
+
+ if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) {
+ kfree(smp->link_key);
+ smp->link_key = NULL;
+ return;
+ }
}
static void smp_allow_key_dist(struct smp_chan *smp)
@@ -715,6 +1121,35 @@ static void smp_allow_key_dist(struct smp_chan *smp)
SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO);
}
+static void sc_generate_ltk(struct smp_chan *smp)
+{
+ /* These constants are as specified in the core specification.
+ * In ASCII they spell out to 'tmp2' and 'brle'.
+ */
+ const u8 tmp2[4] = { 0x32, 0x70, 0x6d, 0x74 };
+ const u8 brle[4] = { 0x65, 0x6c, 0x72, 0x62 };
+ struct hci_conn *hcon = smp->conn->hcon;
+ struct hci_dev *hdev = hcon->hdev;
+ struct link_key *key;
+
+ key = hci_find_link_key(hdev, &hcon->dst);
+ if (!key) {
+ BT_ERR("%s No Link Key found to generate LTK", hdev->name);
+ return;
+ }
+
+ if (key->type == HCI_LK_DEBUG_COMBINATION)
+ set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
+
+ if (smp_h6(smp->tfm_cmac, key->val, tmp2, smp->tk))
+ return;
+
+ if (smp_h6(smp->tfm_cmac, smp->tk, brle, smp->tk))
+ return;
+
+ sc_add_ltk(smp);
+}
+
static void smp_distribute_keys(struct smp_chan *smp)
{
struct smp_cmd_pairing *req, *rsp;
@@ -743,6 +1178,16 @@ static void smp_distribute_keys(struct smp_chan *smp)
*keydist &= req->resp_key_dist;
}
+ if (test_bit(SMP_FLAG_SC, &smp->flags)) {
+ if (hcon->type == LE_LINK && (*keydist & SMP_DIST_LINK_KEY))
+ sc_generate_link_key(smp);
+ if (hcon->type == ACL_LINK && (*keydist & SMP_DIST_ENC_KEY))
+ sc_generate_ltk(smp);
+
+ /* Clear the keys which are generated but not distributed */
+ *keydist &= ~SMP_SC_NO_DIST;
+ }
+
BT_DBG("keydist 0x%x", *keydist);
if (*keydist & SMP_DIST_ENC_KEY) {
@@ -854,6 +1299,14 @@ static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
return NULL;
}
+ smp->tfm_cmac = crypto_alloc_hash("cmac(aes)", 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(smp->tfm_cmac)) {
+ BT_ERR("Unable to create CMAC crypto context");
+ crypto_free_blkcipher(smp->tfm_aes);
+ kfree(smp);
+ return NULL;
+ }
+
smp->conn = conn;
chan->data = smp;
@@ -866,6 +1319,213 @@ static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
return smp;
}
+static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16], u8 ltk[16])
+{
+ struct hci_conn *hcon = smp->conn->hcon;
+ u8 *na, *nb, a[7], b[7];
+
+ if (hcon->out) {
+ na = smp->prnd;
+ nb = smp->rrnd;
+ } else {
+ na = smp->rrnd;
+ nb = smp->prnd;
+ }
+
+ memcpy(a, &hcon->init_addr, 6);
+ memcpy(b, &hcon->resp_addr, 6);
+ a[6] = hcon->init_addr_type;
+ b[6] = hcon->resp_addr_type;
+
+ return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk);
+}
+
+static void sc_dhkey_check(struct smp_chan *smp)
+{
+ struct hci_conn *hcon = smp->conn->hcon;
+ struct smp_cmd_dhkey_check check;
+ u8 a[7], b[7], *local_addr, *remote_addr;
+ u8 io_cap[3], r[16];
+
+ memcpy(a, &hcon->init_addr, 6);
+ memcpy(b, &hcon->resp_addr, 6);
+ a[6] = hcon->init_addr_type;
+ b[6] = hcon->resp_addr_type;
+
+ if (hcon->out) {
+ local_addr = a;
+ remote_addr = b;
+ memcpy(io_cap, &smp->preq[1], 3);
+ } else {
+ local_addr = b;
+ remote_addr = a;
+ memcpy(io_cap, &smp->prsp[1], 3);
+ }
+
+ memset(r, 0, sizeof(r));
+
+ 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);
+
+ smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof(check), &check);
+}
+
+static u8 sc_passkey_send_confirm(struct smp_chan *smp)
+{
+ struct l2cap_conn *conn = smp->conn;
+ struct hci_conn *hcon = conn->hcon;
+ struct smp_cmd_pairing_confirm cfm;
+ u8 r;
+
+ r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
+ r |= 0x80;
+
+ get_random_bytes(smp->prnd, sizeof(smp->prnd));
+
+ if (smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, r,
+ cfm.confirm_val))
+ return SMP_UNSPECIFIED;
+
+ smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
+
+ return 0;
+}
+
+static u8 sc_passkey_round(struct smp_chan *smp, u8 smp_op)
+{
+ struct l2cap_conn *conn = smp->conn;
+ struct hci_conn *hcon = conn->hcon;
+ struct hci_dev *hdev = hcon->hdev;
+ u8 cfm[16], r;
+
+ /* Ignore the PDU if we've already done 20 rounds (0 - 19) */
+ if (smp->passkey_round >= 20)
+ return 0;
+
+ switch (smp_op) {
+ case SMP_CMD_PAIRING_RANDOM:
+ r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01);
+ r |= 0x80;
+
+ if (smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
+ smp->rrnd, r, cfm))
+ return SMP_UNSPECIFIED;
+
+ if (memcmp(smp->pcnf, cfm, 16))
+ return SMP_CONFIRM_FAILED;
+
+ smp->passkey_round++;
+
+ if (smp->passkey_round == 20) {
+ /* Generate MacKey and LTK */
+ if (sc_mackey_and_ltk(smp, smp->mackey, smp->tk))
+ return SMP_UNSPECIFIED;
+ }
+
+ /* The round is only complete when the initiator
+ * receives pairing random.
+ */
+ if (!hcon->out) {
+ smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
+ sizeof(smp->prnd), smp->prnd);
+ if (smp->passkey_round == 20)
+ SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
+ else
+ SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
+ return 0;
+ }
+
+ /* Start the next round */
+ if (smp->passkey_round != 20)
+ return sc_passkey_round(smp, 0);
+
+ /* Passkey rounds are complete - start DHKey Check */
+ sc_dhkey_check(smp);
+ SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
+
+ break;
+
+ case SMP_CMD_PAIRING_CONFIRM:
+ if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
+ set_bit(SMP_FLAG_CFM_PENDING, &smp->flags);
+ return 0;
+ }
+
+ SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
+
+ if (hcon->out) {
+ smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM,
+ sizeof(smp->prnd), smp->prnd);
+ return 0;
+ }
+
+ return sc_passkey_send_confirm(smp);
+
+ case SMP_CMD_PUBLIC_KEY:
+ default:
+ /* Initiating device starts the round */
+ if (!hcon->out)
+ return 0;
+
+ BT_DBG("%s Starting passkey round %u", hdev->name,
+ smp->passkey_round + 1);
+
+ SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
+
+ return sc_passkey_send_confirm(smp);
+ }
+
+ return 0;
+}
+
+static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey)
+{
+ struct l2cap_conn *conn = smp->conn;
+ struct hci_conn *hcon = conn->hcon;
+ u8 smp_op;
+
+ clear_bit(SMP_FLAG_WAIT_USER, &smp->flags);
+
+ switch (mgmt_op) {
+ case MGMT_OP_USER_PASSKEY_NEG_REPLY:
+ smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED);
+ return 0;
+ case MGMT_OP_USER_CONFIRM_NEG_REPLY:
+ smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED);
+ return 0;
+ case MGMT_OP_USER_PASSKEY_REPLY:
+ hcon->passkey_notify = le32_to_cpu(passkey);
+ smp->passkey_round = 0;
+
+ if (test_and_clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags))
+ smp_op = SMP_CMD_PAIRING_CONFIRM;
+ else
+ smp_op = 0;
+
+ if (sc_passkey_round(smp, smp_op))
+ return -EIO;
+
+ return 0;
+ }
+
+ /* Initiator sends DHKey check first */
+ if (hcon->out) {
+ sc_dhkey_check(smp);
+ SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
+ } else if (test_and_clear_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags)) {
+ sc_dhkey_check(smp);
+ sc_add_ltk(smp);
+ }
+
+ return 0;
+}
+
int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey)
{
struct l2cap_conn *conn = hcon->l2cap_data;
@@ -891,6 +1551,11 @@ int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey)
smp = chan->data;
+ if (test_bit(SMP_FLAG_SC, &smp->flags)) {
+ err = sc_user_reply(smp, mgmt_op, passkey);
+ goto unlock;
+ }
+
switch (mgmt_op) {
case MGMT_OP_USER_PASSKEY_REPLY:
value = le32_to_cpu(passkey);
@@ -926,6 +1591,46 @@ unlock:
return err;
}
+static void build_bredr_pairing_cmd(struct smp_chan *smp,
+ struct smp_cmd_pairing *req,
+ struct smp_cmd_pairing *rsp)
+{
+ struct l2cap_conn *conn = smp->conn;
+ struct hci_dev *hdev = conn->hcon->hdev;
+ u8 local_dist = 0, remote_dist = 0;
+
+ if (test_bit(HCI_BONDABLE, &hdev->dev_flags)) {
+ local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
+ remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN;
+ }
+
+ if (test_bit(HCI_RPA_RESOLVING, &hdev->dev_flags))
+ remote_dist |= SMP_DIST_ID_KEY;
+
+ if (test_bit(HCI_PRIVACY, &hdev->dev_flags))
+ local_dist |= SMP_DIST_ID_KEY;
+
+ if (!rsp) {
+ memset(req, 0, sizeof(*req));
+
+ req->init_key_dist = local_dist;
+ req->resp_key_dist = remote_dist;
+ req->max_key_size = SMP_MAX_ENC_KEY_SIZE;
+
+ smp->remote_key_dist = remote_dist;
+
+ return;
+ }
+
+ memset(rsp, 0, sizeof(*rsp));
+
+ rsp->max_key_size = SMP_MAX_ENC_KEY_SIZE;
+ rsp->init_key_dist = req->init_key_dist & remote_dist;
+ rsp->resp_key_dist = req->resp_key_dist & local_dist;
+
+ smp->remote_key_dist = rsp->init_key_dist;
+}
+
static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
{
struct smp_cmd_pairing rsp, *req = (void *) skb->data;
@@ -952,16 +1657,49 @@ static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
return SMP_UNSPECIFIED;
/* We didn't start the pairing, so match remote */
- auth = req->auth_req & AUTH_REQ_MASK;
+ auth = req->auth_req & AUTH_REQ_MASK(hdev);
if (!test_bit(HCI_BONDABLE, &hdev->dev_flags) &&
(auth & SMP_AUTH_BONDING))
return SMP_PAIRING_NOTSUPP;
+ if (test_bit(HCI_SC_ONLY, &hdev->dev_flags) && !(auth & SMP_AUTH_SC))
+ return SMP_AUTH_REQUIREMENTS;
+
smp->preq[0] = SMP_CMD_PAIRING_REQ;
memcpy(&smp->preq[1], req, sizeof(*req));
skb_pull(skb, sizeof(*req));
+ /* SMP over BR/EDR requires special treatment */
+ if (conn->hcon->type == ACL_LINK) {
+ /* We must have a BR/EDR SC link */
+ if (!test_bit(HCI_CONN_AES_CCM, &conn->hcon->flags))
+ return SMP_CROSS_TRANSP_NOT_ALLOWED;
+
+ set_bit(SMP_FLAG_SC, &smp->flags);
+
+ build_bredr_pairing_cmd(smp, req, &rsp);
+
+ key_size = min(req->max_key_size, rsp.max_key_size);
+ if (check_enc_key_size(conn, key_size))
+ return SMP_ENC_KEY_SIZE;
+
+ /* Clear bits which are generated but not distributed */
+ smp->remote_key_dist &= ~SMP_SC_NO_DIST;
+
+ smp->prsp[0] = SMP_CMD_PAIRING_RSP;
+ memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
+ smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
+
+ smp_distribute_keys(smp);
+ return 0;
+ }
+
+ build_pairing_cmd(conn, req, &rsp, auth);
+
+ if (rsp.auth_req & SMP_AUTH_SC)
+ set_bit(SMP_FLAG_SC, &smp->flags);
+
if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
sec_level = BT_SECURITY_MEDIUM;
else
@@ -970,7 +1708,7 @@ static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
if (sec_level > conn->hcon->pending_sec_level)
conn->hcon->pending_sec_level = sec_level;
- /* If we need MITM check that it can be acheived */
+ /* If we need MITM check that it can be achieved */
if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
u8 method;
@@ -980,8 +1718,6 @@ static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
return SMP_AUTH_REQUIREMENTS;
}
- build_pairing_cmd(conn, req, &rsp, auth);
-
key_size = min(req->max_key_size, rsp.max_key_size);
if (check_enc_key_size(conn, key_size))
return SMP_ENC_KEY_SIZE;
@@ -992,7 +1728,18 @@ static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
- SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
+
+ clear_bit(SMP_FLAG_INITIATOR, &smp->flags);
+
+ if (test_bit(SMP_FLAG_SC, &smp->flags)) {
+ SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
+ /* Clear bits which are generated but not distributed */
+ smp->remote_key_dist &= ~SMP_SC_NO_DIST;
+ /* Wait for Public Key from Initiating Device */
+ return 0;
+ } else {
+ SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
+ }
/* Request setup of TK */
ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability);
@@ -1002,11 +1749,46 @@ static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
return 0;
}
+static u8 sc_send_public_key(struct smp_chan *smp)
+{
+ struct hci_dev *hdev = smp->conn->hcon->hdev;
+
+ BT_DBG("");
+
+ if (test_bit(HCI_USE_DEBUG_KEYS, &hdev->dev_flags)) {
+ BT_DBG("Using debug keys");
+ memcpy(smp->local_pk, debug_pk, 64);
+ memcpy(smp->local_sk, debug_sk, 32);
+ set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
+ } else {
+ while (true) {
+ /* Generate local key pair for Secure Connections */
+ if (!ecc_make_key(smp->local_pk, smp->local_sk))
+ return SMP_UNSPECIFIED;
+
+ /* This is unlikely, but we need to check that
+ * we didn't accidentially generate a debug key.
+ */
+ if (memcmp(smp->local_sk, debug_sk, 32))
+ break;
+ }
+ }
+
+ SMP_DBG("Local Public Key X: %32phN", smp->local_pk);
+ SMP_DBG("Local Public Key Y: %32phN", &smp->local_pk[32]);
+ SMP_DBG("Local Private Key: %32phN", smp->local_sk);
+
+ smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk);
+
+ return 0;
+}
+
static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
{
struct smp_cmd_pairing *req, *rsp = (void *) skb->data;
struct l2cap_chan *chan = conn->smp;
struct smp_chan *smp = chan->data;
+ struct hci_dev *hdev = conn->hcon->hdev;
u8 key_size, auth;
int ret;
@@ -1026,9 +1808,33 @@ static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
if (check_enc_key_size(conn, key_size))
return SMP_ENC_KEY_SIZE;
- auth = rsp->auth_req & AUTH_REQ_MASK;
+ auth = rsp->auth_req & AUTH_REQ_MASK(hdev);
+
+ if (test_bit(HCI_SC_ONLY, &hdev->dev_flags) && !(auth & SMP_AUTH_SC))
+ return SMP_AUTH_REQUIREMENTS;
+
+ smp->prsp[0] = SMP_CMD_PAIRING_RSP;
+ memcpy(&smp->prsp[1], rsp, sizeof(*rsp));
- /* If we need MITM check that it can be acheived */
+ /* Update remote key distribution in case the remote cleared
+ * some bits that we had enabled in our request.
+ */
+ smp->remote_key_dist &= rsp->resp_key_dist;
+
+ /* For BR/EDR this means we're done and can start phase 3 */
+ if (conn->hcon->type == ACL_LINK) {
+ /* Clear bits which are generated but not distributed */
+ smp->remote_key_dist &= ~SMP_SC_NO_DIST;
+ smp_distribute_keys(smp);
+ return 0;
+ }
+
+ if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC))
+ set_bit(SMP_FLAG_SC, &smp->flags);
+ else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH)
+ conn->hcon->pending_sec_level = BT_SECURITY_HIGH;
+
+ /* If we need MITM check that it can be achieved */
if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) {
u8 method;
@@ -1040,14 +1846,18 @@ static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
get_random_bytes(smp->prnd, sizeof(smp->prnd));
- smp->prsp[0] = SMP_CMD_PAIRING_RSP;
- memcpy(&smp->prsp[1], rsp, sizeof(*rsp));
-
/* Update remote key distribution in case the remote cleared
* some bits that we had enabled in our request.
*/
smp->remote_key_dist &= rsp->resp_key_dist;
+ if (test_bit(SMP_FLAG_SC, &smp->flags)) {
+ /* Clear bits which are generated but not distributed */
+ smp->remote_key_dist &= ~SMP_SC_NO_DIST;
+ SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY);
+ return sc_send_public_key(smp);
+ }
+
auth |= req->auth_req;
ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability);
@@ -1063,6 +1873,28 @@ static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
return 0;
}
+static u8 sc_check_confirm(struct smp_chan *smp)
+{
+ struct l2cap_conn *conn = smp->conn;
+
+ BT_DBG("");
+
+ /* Public Key exchange must happen before any other steps */
+ if (!test_bit(SMP_FLAG_REMOTE_PK, &smp->flags))
+ return SMP_UNSPECIFIED;
+
+ if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
+ return sc_passkey_round(smp, SMP_CMD_PAIRING_CONFIRM);
+
+ if (conn->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;
+}
+
static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb)
{
struct l2cap_chan *chan = conn->smp;
@@ -1076,6 +1908,9 @@ static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb)
memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf));
skb_pull(skb, sizeof(smp->pcnf));
+ if (test_bit(SMP_FLAG_SC, &smp->flags))
+ return sc_check_confirm(smp);
+
if (conn->hcon->out) {
smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
smp->prnd);
@@ -1095,6 +1930,10 @@ static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
{
struct l2cap_chan *chan = conn->smp;
struct smp_chan *smp = chan->data;
+ struct hci_conn *hcon = conn->hcon;
+ u8 *pkax, *pkbx, *na, *nb;
+ u32 passkey;
+ int err;
BT_DBG("conn %p", conn);
@@ -1104,7 +1943,75 @@ static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd));
skb_pull(skb, sizeof(smp->rrnd));
- return smp_random(smp);
+ if (!test_bit(SMP_FLAG_SC, &smp->flags))
+ return smp_random(smp);
+
+ if (hcon->out) {
+ pkax = smp->local_pk;
+ pkbx = smp->remote_pk;
+ na = smp->prnd;
+ nb = smp->rrnd;
+ } else {
+ pkax = smp->remote_pk;
+ pkbx = smp->local_pk;
+ na = smp->rrnd;
+ nb = smp->prnd;
+ }
+
+ 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);
+
+ if (hcon->out) {
+ u8 cfm[16];
+
+ err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk,
+ smp->rrnd, 0, cfm);
+ if (err)
+ return SMP_UNSPECIFIED;
+
+ if (memcmp(smp->pcnf, cfm, 16))
+ return SMP_CONFIRM_FAILED;
+ } else {
+ smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
+ smp->prnd);
+ SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
+ }
+
+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 || smp->method == REQ_OOB) {
+ if (hcon->out) {
+ sc_dhkey_check(smp);
+ SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
+ }
+ return 0;
+ }
+
+ err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey);
+ if (err)
+ return SMP_UNSPECIFIED;
+
+ err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, hcon->type,
+ hcon->dst_type, passkey, 0);
+ if (err)
+ return SMP_UNSPECIFIED;
+
+ set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
+
+ return 0;
}
static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level)
@@ -1112,8 +2019,7 @@ static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level)
struct smp_ltk *key;
struct hci_conn *hcon = conn->hcon;
- key = hci_find_ltk_by_addr(hcon->hdev, &hcon->dst, hcon->dst_type,
- hcon->role);
+ key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role);
if (!key)
return false;
@@ -1132,20 +2038,21 @@ static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level)
return true;
}
-bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level)
+bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level,
+ enum smp_key_pref key_pref)
{
if (sec_level == BT_SECURITY_LOW)
return true;
- /* If we're encrypted with an STK always claim insufficient
- * security. This way we allow the connection to be re-encrypted
- * with an LTK, even if the LTK provides the same level of
- * security. Only exception is if we don't have an LTK (e.g.
- * because of key distribution bits).
+ /* If we're encrypted with an STK but the caller prefers using
+ * LTK claim insufficient security. This way we allow the
+ * connection to be re-encrypted with an LTK, even if the LTK
+ * provides the same level of security. Only exception is if we
+ * don't have an LTK (e.g. because of key distribution bits).
*/
- if (test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) &&
- hci_find_ltk_by_addr(hcon->hdev, &hcon->dst, hcon->dst_type,
- hcon->role))
+ if (key_pref == SMP_USE_LTK &&
+ test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) &&
+ hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role))
return false;
if (hcon->sec_level >= sec_level)
@@ -1159,6 +2066,7 @@ static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
struct smp_cmd_security_req *rp = (void *) skb->data;
struct smp_cmd_pairing cp;
struct hci_conn *hcon = conn->hcon;
+ struct hci_dev *hdev = hcon->hdev;
struct smp_chan *smp;
u8 sec_level, auth;
@@ -1170,14 +2078,17 @@ static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
if (hcon->role != HCI_ROLE_MASTER)
return SMP_CMD_NOTSUPP;
- auth = rp->auth_req & AUTH_REQ_MASK;
+ auth = rp->auth_req & AUTH_REQ_MASK(hdev);
+
+ if (test_bit(HCI_SC_ONLY, &hdev->dev_flags) && !(auth & SMP_AUTH_SC))
+ return SMP_AUTH_REQUIREMENTS;
if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT)
sec_level = BT_SECURITY_MEDIUM;
else
sec_level = authreq_to_seclevel(auth);
- if (smp_sufficient_security(hcon, sec_level))
+ if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
return 0;
if (sec_level > hcon->pending_sec_level)
@@ -1227,7 +2138,7 @@ int smp_conn_security(struct hci_conn *hcon, __u8 sec_level)
if (!test_bit(HCI_LE_ENABLED, &hcon->hdev->dev_flags))
return 1;
- if (smp_sufficient_security(hcon, sec_level))
+ if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK))
return 1;
if (sec_level > hcon->pending_sec_level)
@@ -1253,6 +2164,9 @@ int smp_conn_security(struct hci_conn *hcon, __u8 sec_level)
authreq = seclevel_to_authreq(sec_level);
+ if (test_bit(HCI_SC_ENABLED, &hcon->hdev->dev_flags))
+ authreq |= SMP_AUTH_SC;
+
/* Require MITM if IO Capability allows or the security level
* requires it.
*/
@@ -1329,7 +2243,6 @@ static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb)
skb_pull(skb, sizeof(*rp));
- hci_dev_lock(hdev);
authenticated = (hcon->sec_level == BT_SECURITY_HIGH);
ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK,
authenticated, smp->tk, smp->enc_key_size,
@@ -1337,7 +2250,6 @@ static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb)
smp->ltk = ltk;
if (!(smp->remote_key_dist & KEY_DIST_MASK))
smp_distribute_keys(smp);
- hci_dev_unlock(hdev);
return 0;
}
@@ -1384,8 +2296,6 @@ static int smp_cmd_ident_addr_info(struct l2cap_conn *conn,
skb_pull(skb, sizeof(*info));
- hci_dev_lock(hcon->hdev);
-
/* Strictly speaking the Core Specification (4.1) allows sending
* an empty address which would force us to rely on just the IRK
* as "identity information". However, since such
@@ -1413,8 +2323,6 @@ distribute:
if (!(smp->remote_key_dist & KEY_DIST_MASK))
smp_distribute_keys(smp);
- hci_dev_unlock(hcon->hdev);
-
return 0;
}
@@ -1423,7 +2331,6 @@ static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb)
struct smp_cmd_sign_info *rp = (void *) skb->data;
struct l2cap_chan *chan = conn->smp;
struct smp_chan *smp = chan->data;
- struct hci_dev *hdev = conn->hcon->hdev;
struct smp_csrk *csrk;
BT_DBG("conn %p", conn);
@@ -1436,7 +2343,6 @@ static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb)
skb_pull(skb, sizeof(*rp));
- hci_dev_lock(hdev);
csrk = kzalloc(sizeof(*csrk), GFP_KERNEL);
if (csrk) {
csrk->master = 0x01;
@@ -1444,7 +2350,234 @@ static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb)
}
smp->csrk = csrk;
smp_distribute_keys(smp);
- hci_dev_unlock(hdev);
+
+ return 0;
+}
+
+static u8 sc_select_method(struct smp_chan *smp)
+{
+ struct l2cap_conn *conn = smp->conn;
+ struct hci_conn *hcon = conn->hcon;
+ 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
+ * first byte which contains the opcode.
+ */
+ if (hcon->out) {
+ local = (void *) &smp->preq[1];
+ remote = (void *) &smp->prsp[1];
+ } else {
+ local = (void *) &smp->prsp[1];
+ remote = (void *) &smp->preq[1];
+ }
+
+ local_io = local->io_capability;
+ remote_io = remote->io_capability;
+
+ local_mitm = (local->auth_req & SMP_AUTH_MITM);
+ remote_mitm = (remote->auth_req & SMP_AUTH_MITM);
+
+ /* If either side wants MITM, look up the method from the table,
+ * otherwise use JUST WORKS.
+ */
+ if (local_mitm || remote_mitm)
+ method = get_auth_method(smp, local_io, remote_io);
+ else
+ method = JUST_WORKS;
+
+ /* Don't confirm locally initiated pairing attempts */
+ if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags))
+ method = JUST_WORKS;
+
+ return method;
+}
+
+static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb)
+{
+ struct smp_cmd_public_key *key = (void *) skb->data;
+ struct hci_conn *hcon = conn->hcon;
+ struct l2cap_chan *chan = conn->smp;
+ struct smp_chan *smp = chan->data;
+ struct hci_dev *hdev = hcon->hdev;
+ struct smp_cmd_pairing_confirm cfm;
+ int err;
+
+ BT_DBG("conn %p", conn);
+
+ if (skb->len < sizeof(*key))
+ return SMP_INVALID_PARAMS;
+
+ memcpy(smp->remote_pk, key, 64);
+
+ /* Non-initiating device sends its public key after receiving
+ * the key from the initiating device.
+ */
+ if (!hcon->out) {
+ err = sc_send_public_key(smp);
+ if (err)
+ return err;
+ }
+
+ SMP_DBG("Remote Public Key X: %32phN", smp->remote_pk);
+ SMP_DBG("Remote Public Key Y: %32phN", &smp->remote_pk[32]);
+
+ if (!ecdh_shared_secret(smp->remote_pk, smp->local_sk, smp->dhkey))
+ return SMP_UNSPECIFIED;
+
+ SMP_DBG("DHKey %32phN", smp->dhkey);
+
+ set_bit(SMP_FLAG_REMOTE_PK, &smp->flags);
+
+ smp->method = sc_select_method(smp);
+
+ BT_DBG("%s selected method 0x%02x", hdev->name, smp->method);
+
+ /* JUST_WORKS and JUST_CFM result in an unauthenticated key */
+ if (smp->method == JUST_WORKS || smp->method == JUST_CFM)
+ hcon->pending_sec_level = BT_SECURITY_MEDIUM;
+ else
+ hcon->pending_sec_level = BT_SECURITY_FIPS;
+
+ if (!memcmp(debug_pk, smp->remote_pk, 64))
+ set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags);
+
+ if (smp->method == DSP_PASSKEY) {
+ get_random_bytes(&hcon->passkey_notify,
+ sizeof(hcon->passkey_notify));
+ hcon->passkey_notify %= 1000000;
+ hcon->passkey_entered = 0;
+ smp->passkey_round = 0;
+ if (mgmt_user_passkey_notify(hdev, &hcon->dst, hcon->type,
+ hcon->dst_type,
+ hcon->passkey_notify,
+ hcon->passkey_entered))
+ return SMP_UNSPECIFIED;
+ SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
+ 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);
+
+ if (smp->method == REQ_PASSKEY) {
+ if (mgmt_user_passkey_request(hdev, &hcon->dst, hcon->type,
+ hcon->dst_type))
+ return SMP_UNSPECIFIED;
+ SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM);
+ set_bit(SMP_FLAG_WAIT_USER, &smp->flags);
+ return 0;
+ }
+
+ /* The Initiating device waits for the non-initiating device to
+ * send the confirm value.
+ */
+ if (conn->hcon->out)
+ return 0;
+
+ err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd,
+ 0, cfm.confirm_val);
+ if (err)
+ return SMP_UNSPECIFIED;
+
+ smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm);
+ SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM);
+
+ return 0;
+}
+
+static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb)
+{
+ struct smp_cmd_dhkey_check *check = (void *) skb->data;
+ struct l2cap_chan *chan = conn->smp;
+ struct hci_conn *hcon = conn->hcon;
+ struct smp_chan *smp = chan->data;
+ u8 a[7], b[7], *local_addr, *remote_addr;
+ u8 io_cap[3], r[16], e[16];
+ int err;
+
+ BT_DBG("conn %p", conn);
+
+ if (skb->len < sizeof(*check))
+ return SMP_INVALID_PARAMS;
+
+ memcpy(a, &hcon->init_addr, 6);
+ memcpy(b, &hcon->resp_addr, 6);
+ a[6] = hcon->init_addr_type;
+ b[6] = hcon->resp_addr_type;
+
+ if (hcon->out) {
+ local_addr = a;
+ remote_addr = b;
+ memcpy(io_cap, &smp->prsp[1], 3);
+ } else {
+ local_addr = b;
+ remote_addr = a;
+ memcpy(io_cap, &smp->preq[1], 3);
+ }
+
+ memset(r, 0, sizeof(r));
+
+ if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY)
+ put_unaligned_le32(hcon->passkey_notify, r);
+
+ err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r,
+ io_cap, remote_addr, local_addr, e);
+ if (err)
+ return SMP_UNSPECIFIED;
+
+ if (memcmp(check->e, e, 16))
+ return SMP_DHKEY_CHECK_FAILED;
+
+ if (!hcon->out) {
+ if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) {
+ set_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags);
+ return 0;
+ }
+
+ /* Slave sends DHKey check as response to master */
+ sc_dhkey_check(smp);
+ }
+
+ sc_add_ltk(smp);
+
+ if (hcon->out) {
+ hci_le_start_enc(hcon, 0, 0, smp->tk);
+ hcon->enc_key_size = smp->enc_key_size;
+ }
+
+ return 0;
+}
+
+static int smp_cmd_keypress_notify(struct l2cap_conn *conn,
+ struct sk_buff *skb)
+{
+ struct smp_cmd_keypress_notify *kp = (void *) skb->data;
+
+ BT_DBG("value 0x%02x", kp->value);
return 0;
}
@@ -1457,11 +2590,6 @@ static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb)
__u8 code, reason;
int err = 0;
- if (hcon->type != LE_LINK) {
- kfree_skb(skb);
- return 0;
- }
-
if (skb->len < 1)
return -EILSEQ;
@@ -1533,6 +2661,18 @@ static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb)
reason = smp_cmd_sign_info(conn, skb);
break;
+ case SMP_CMD_PUBLIC_KEY:
+ reason = smp_cmd_public_key(conn, skb);
+ break;
+
+ case SMP_CMD_DHKEY_CHECK:
+ reason = smp_cmd_dhkey_check(conn, skb);
+ break;
+
+ case SMP_CMD_KEYPRESS_NOTIFY:
+ reason = smp_cmd_keypress_notify(conn, skb);
+ break;
+
default:
BT_DBG("Unknown command code 0x%2.2x", code);
reason = SMP_CMD_NOTSUPP;
@@ -1568,6 +2708,74 @@ static void smp_teardown_cb(struct l2cap_chan *chan, int err)
l2cap_chan_put(chan);
}
+static void bredr_pairing(struct l2cap_chan *chan)
+{
+ struct l2cap_conn *conn = chan->conn;
+ struct hci_conn *hcon = conn->hcon;
+ struct hci_dev *hdev = hcon->hdev;
+ struct smp_cmd_pairing req;
+ struct smp_chan *smp;
+
+ BT_DBG("chan %p", chan);
+
+ /* Only new pairings are interesting */
+ if (!test_bit(HCI_CONN_NEW_LINK_KEY, &hcon->flags))
+ return;
+
+ /* Don't bother if we're not encrypted */
+ if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
+ return;
+
+ /* Only master may initiate SMP over BR/EDR */
+ if (hcon->role != HCI_ROLE_MASTER)
+ return;
+
+ /* Secure Connections support must be enabled */
+ if (!test_bit(HCI_SC_ENABLED, &hdev->dev_flags))
+ return;
+
+ /* BR/EDR must use Secure Connections for SMP */
+ if (!test_bit(HCI_CONN_AES_CCM, &hcon->flags) &&
+ !test_bit(HCI_FORCE_LESC, &hdev->dbg_flags))
+ return;
+
+ /* If our LE support is not enabled don't do anything */
+ if (!test_bit(HCI_LE_ENABLED, &hdev->dev_flags))
+ return;
+
+ /* Don't bother if remote LE support is not enabled */
+ if (!lmp_host_le_capable(hcon))
+ return;
+
+ /* Remote must support SMP fixed chan for BR/EDR */
+ if (!(conn->remote_fixed_chan & L2CAP_FC_SMP_BREDR))
+ return;
+
+ /* Don't bother if SMP is already ongoing */
+ if (chan->data)
+ return;
+
+ smp = smp_chan_create(conn);
+ if (!smp) {
+ BT_ERR("%s unable to create SMP context for BR/EDR",
+ hdev->name);
+ return;
+ }
+
+ set_bit(SMP_FLAG_SC, &smp->flags);
+
+ BT_DBG("%s starting SMP over BR/EDR", hdev->name);
+
+ /* Prepare and send the BR/EDR SMP Pairing Request */
+ build_bredr_pairing_cmd(smp, &req, NULL);
+
+ smp->preq[0] = SMP_CMD_PAIRING_REQ;
+ memcpy(&smp->preq[1], &req, sizeof(req));
+
+ smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(req), &req);
+ SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP);
+}
+
static void smp_resume_cb(struct l2cap_chan *chan)
{
struct smp_chan *smp = chan->data;
@@ -1576,6 +2784,11 @@ static void smp_resume_cb(struct l2cap_chan *chan)
BT_DBG("chan %p", chan);
+ if (hcon->type == ACL_LINK) {
+ bredr_pairing(chan);
+ return;
+ }
+
if (!smp)
return;
@@ -1590,11 +2803,15 @@ static void smp_resume_cb(struct l2cap_chan *chan)
static void smp_ready_cb(struct l2cap_chan *chan)
{
struct l2cap_conn *conn = chan->conn;
+ struct hci_conn *hcon = conn->hcon;
BT_DBG("chan %p", chan);
conn->smp = chan;
l2cap_chan_hold(chan);
+
+ if (hcon->type == ACL_LINK && test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
+ bredr_pairing(chan);
}
static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
@@ -1647,7 +2864,6 @@ static const struct l2cap_ops smp_chan_ops = {
.suspend = l2cap_chan_no_suspend,
.set_shutdown = l2cap_chan_no_set_shutdown,
.get_sndtimeo = l2cap_chan_no_get_sndtimeo,
- .memcpy_fromiovec = l2cap_chan_no_memcpy_fromiovec,
};
static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan)
@@ -1668,6 +2884,13 @@ static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan)
chan->omtu = pchan->omtu;
chan->mode = pchan->mode;
+ /* Other L2CAP channels may request SMP routines in order to
+ * change the security level. This means that the SMP channel
+ * lock must be considered in its own category to avoid lockdep
+ * warnings.
+ */
+ atomic_set(&chan->nesting, L2CAP_NESTING_SMP);
+
BT_DBG("created chan %p", chan);
return chan;
@@ -1689,56 +2912,58 @@ static const struct l2cap_ops smp_root_chan_ops = {
.resume = l2cap_chan_no_resume,
.set_shutdown = l2cap_chan_no_set_shutdown,
.get_sndtimeo = l2cap_chan_no_get_sndtimeo,
- .memcpy_fromiovec = l2cap_chan_no_memcpy_fromiovec,
};
-int smp_register(struct hci_dev *hdev)
+static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid)
{
struct l2cap_chan *chan;
struct crypto_blkcipher *tfm_aes;
- BT_DBG("%s", hdev->name);
+ if (cid == L2CAP_CID_SMP_BREDR) {
+ tfm_aes = NULL;
+ goto create_chan;
+ }
- tfm_aes = crypto_alloc_blkcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC);
+ tfm_aes = crypto_alloc_blkcipher("ecb(aes)", 0, 0);
if (IS_ERR(tfm_aes)) {
- int err = PTR_ERR(tfm_aes);
BT_ERR("Unable to create crypto context");
- return err;
+ return ERR_PTR(PTR_ERR(tfm_aes));
}
+create_chan:
chan = l2cap_chan_create();
if (!chan) {
crypto_free_blkcipher(tfm_aes);
- return -ENOMEM;
+ return ERR_PTR(-ENOMEM);
}
chan->data = tfm_aes;
- l2cap_add_scid(chan, L2CAP_CID_SMP);
+ l2cap_add_scid(chan, cid);
l2cap_chan_set_defaults(chan);
bacpy(&chan->src, &hdev->bdaddr);
- chan->src_type = BDADDR_LE_PUBLIC;
+ if (cid == L2CAP_CID_SMP)
+ chan->src_type = BDADDR_LE_PUBLIC;
+ else
+ chan->src_type = BDADDR_BREDR;
chan->state = BT_LISTEN;
chan->mode = L2CAP_MODE_BASIC;
chan->imtu = L2CAP_DEFAULT_MTU;
chan->ops = &smp_root_chan_ops;
- hdev->smp_data = chan;
+ /* Set correct nesting level for a parent/listening channel */
+ atomic_set(&chan->nesting, L2CAP_NESTING_PARENT);
- return 0;
+ return chan;
}
-void smp_unregister(struct hci_dev *hdev)
+static void smp_del_chan(struct l2cap_chan *chan)
{
- struct l2cap_chan *chan = hdev->smp_data;
- struct crypto_blkcipher *tfm_aes;
-
- if (!chan)
- return;
+ struct crypto_blkcipher *tfm_aes;
- BT_DBG("%s chan %p", hdev->name, chan);
+ BT_DBG("chan %p", chan);
tfm_aes = chan->data;
if (tfm_aes) {
@@ -1746,6 +2971,52 @@ void smp_unregister(struct hci_dev *hdev)
crypto_free_blkcipher(tfm_aes);
}
- hdev->smp_data = NULL;
l2cap_chan_put(chan);
}
+
+int smp_register(struct hci_dev *hdev)
+{
+ struct l2cap_chan *chan;
+
+ BT_DBG("%s", hdev->name);
+
+ chan = smp_add_cid(hdev, L2CAP_CID_SMP);
+ if (IS_ERR(chan))
+ return PTR_ERR(chan);
+
+ hdev->smp_data = chan;
+
+ if (!lmp_sc_capable(hdev) &&
+ !test_bit(HCI_FORCE_LESC, &hdev->dbg_flags))
+ return 0;
+
+ chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR);
+ if (IS_ERR(chan)) {
+ int err = PTR_ERR(chan);
+ chan = hdev->smp_data;
+ hdev->smp_data = NULL;
+ smp_del_chan(chan);
+ return err;
+ }
+
+ hdev->smp_bredr_data = chan;
+
+ return 0;
+}
+
+void smp_unregister(struct hci_dev *hdev)
+{
+ struct l2cap_chan *chan;
+
+ if (hdev->smp_bredr_data) {
+ chan = hdev->smp_bredr_data;
+ hdev->smp_bredr_data = NULL;
+ smp_del_chan(chan);
+ }
+
+ if (hdev->smp_data) {
+ chan = hdev->smp_data;
+ hdev->smp_data = NULL;
+ smp_del_chan(chan);
+ }
+}