[deliverable/linux.git] / net / bluetooth / smp.c

/*
   BlueZ - Bluetooth protocol stack for Linux
   Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License version 2 as
   published by the Free Software Foundation;

   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
   OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
   IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
   CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
   WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
   ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

   ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
   COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
   SOFTWARE IS DISCLAIMED.
*/

#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
#include <net/bluetooth/l2cap.h>
#include <net/bluetooth/smp.h>
#include <linux/crypto.h>
#include <crypto/b128ops.h>

static inline void swap128(u8 src[16], u8 dst[16])
{
	int i;
	for (i = 0; i < 16; i++)
		dst[15 - i] = src[i];
}

static inline void swap56(u8 src[7], u8 dst[7])
{
	int i;
	for (i = 0; i < 7; i++)
		dst[6 - i] = src[i];
}

static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r)
{
	struct blkcipher_desc desc;
	struct scatterlist sg;
	int err, iv_len;
	unsigned char iv[128];

	if (tfm == NULL) {
		BT_ERR("tfm %p", tfm);
		return -EINVAL;
	}

	desc.tfm = tfm;
	desc.flags = 0;

	err = crypto_blkcipher_setkey(tfm, k, 16);
	if (err) {
		BT_ERR("cipher setkey failed: %d", err);
		return err;
	}

	sg_init_one(&sg, r, 16);

	iv_len = crypto_blkcipher_ivsize(tfm);
	if (iv_len) {
		memset(&iv, 0xff, iv_len);
		crypto_blkcipher_set_iv(tfm, iv, iv_len);
	}

	err = crypto_blkcipher_encrypt(&desc, &sg, &sg, 16);
	if (err)
		BT_ERR("Encrypt data error %d", err);

	return err;
}

static int smp_c1(struct crypto_blkcipher *tfm, 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])
{
	u8 p1[16], p2[16];
	int err;

	memset(p1, 0, 16);

	/* p1 = pres || preq || _rat || _iat */
	swap56(pres, p1);
	swap56(preq, p1 + 7);
	p1[14] = _rat;
	p1[15] = _iat;

	memset(p2, 0, 16);

	/* p2 = padding || ia || ra */
	baswap((bdaddr_t *) (p2 + 4), ia);
	baswap((bdaddr_t *) (p2 + 10), ra);

	/* res = r XOR p1 */
	u128_xor((u128 *) res, (u128 *) r, (u128 *) p1);

	/* res = e(k, res) */
	err = smp_e(tfm, k, res);
	if (err) {
		BT_ERR("Encrypt data error");
		return err;
	}

	/* res = res XOR p2 */
	u128_xor((u128 *) res, (u128 *) res, (u128 *) p2);

	/* res = e(k, res) */
	err = smp_e(tfm, k, res);
	if (err)
		BT_ERR("Encrypt data error");

	return err;
}

static int smp_s1(struct crypto_blkcipher *tfm, u8 k[16],
			u8 r1[16], u8 r2[16], u8 _r[16])
{
	int err;

	/* Just least significant octets from r1 and r2 are considered */
	memcpy(_r, r1 + 8, 8);
	memcpy(_r + 8, r2 + 8, 8);

	err = smp_e(tfm, k, _r);
	if (err)
		BT_ERR("Encrypt data error");

	return err;
}

static int smp_rand(u8 *buf)
{
	get_random_bytes(buf, 16);

	return 0;
}

static struct sk_buff *smp_build_cmd(struct l2cap_conn *conn, u8 code,
						u16 dlen, void *data)
{
	struct sk_buff *skb;
	struct l2cap_hdr *lh;
	int len;

	len = L2CAP_HDR_SIZE + sizeof(code) + dlen;

	if (len > conn->mtu)
		return NULL;

	skb = bt_skb_alloc(len, GFP_ATOMIC);
	if (!skb)
		return NULL;

	lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
	lh->len = cpu_to_le16(sizeof(code) + dlen);
	lh->cid = cpu_to_le16(L2CAP_CID_SMP);

	memcpy(skb_put(skb, sizeof(code)), &code, sizeof(code));

	memcpy(skb_put(skb, dlen), data, dlen);

	return skb;
}

static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
{
	struct sk_buff *skb = smp_build_cmd(conn, code, len, data);

	BT_DBG("code 0x%2.2x", code);

	if (!skb)
		return;

	hci_send_acl(conn->hcon, skb, 0);
}

static void build_pairing_cmd(struct l2cap_conn *conn,
				struct smp_cmd_pairing *cmd, __u8 authreq)
{
	cmd->io_capability = conn->hcon->io_capability;
	cmd->oob_flag = SMP_OOB_NOT_PRESENT;
	cmd->max_key_size = 16;
	cmd->init_key_dist = 0x00;
	cmd->resp_key_dist = 0x00;
	cmd->auth_req = authreq;
}

static void smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
{
	struct smp_cmd_pairing *rp = (void *) skb->data;

	BT_DBG("conn %p", conn);

	conn->preq[0] = SMP_CMD_PAIRING_REQ;
	memcpy(&conn->preq[1], rp, sizeof(*rp));
	skb_pull(skb, sizeof(*rp));

	rp->io_capability = 0x00;
	rp->oob_flag = 0x00;
	rp->max_key_size = 16;
	rp->init_key_dist = 0x00;
	rp->resp_key_dist = 0x00;
	rp->auth_req &= (SMP_AUTH_BONDING | SMP_AUTH_MITM);

	/* Just works */
	memset(conn->tk, 0, sizeof(conn->tk));

	conn->prsp[0] = SMP_CMD_PAIRING_RSP;
	memcpy(&conn->prsp[1], rp, sizeof(*rp));

	smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(*rp), rp);
}

static void smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
{
	struct smp_cmd_pairing *rp = (void *) skb->data;
	struct smp_cmd_pairing_confirm cp;
	struct crypto_blkcipher *tfm = conn->hcon->hdev->tfm;
	int ret;
	u8 res[16];

	BT_DBG("conn %p", conn);

	/* Just works */
	memset(conn->tk, 0, sizeof(conn->tk));

	conn->prsp[0] = SMP_CMD_PAIRING_RSP;
	memcpy(&conn->prsp[1], rp, sizeof(*rp));
	skb_pull(skb, sizeof(*rp));

	ret = smp_rand(conn->prnd);
	if (ret)
		return;

	ret = smp_c1(tfm, conn->tk, conn->prnd, conn->preq, conn->prsp, 0,
			conn->src, conn->hcon->dst_type, conn->dst, res);
	if (ret)
		return;

	swap128(res, cp.confirm_val);

	smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
}

static void smp_cmd_pairing_confirm(struct l2cap_conn *conn,
							struct sk_buff *skb)
{
	struct crypto_blkcipher *tfm = conn->hcon->hdev->tfm;

	BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");

	memcpy(conn->pcnf, skb->data, sizeof(conn->pcnf));
	skb_pull(skb, sizeof(conn->pcnf));

	if (conn->hcon->out) {
		u8 random[16];

		swap128(conn->prnd, random);
		smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(random),
								random);
	} else {
		struct smp_cmd_pairing_confirm cp;
		int ret;
		u8 res[16];

		ret = smp_rand(conn->prnd);
		if (ret)
			return;

		ret = smp_c1(tfm, conn->tk, conn->prnd, conn->preq, conn->prsp,
						conn->hcon->dst_type, conn->dst,
						0, conn->src, res);
		if (ret)
			return;

		swap128(res, cp.confirm_val);

		smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
	}
}

static void smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
{
	struct hci_conn *hcon = conn->hcon;
	struct crypto_blkcipher *tfm = hcon->hdev->tfm;
	int ret;
	u8 key[16], res[16], random[16], confirm[16];

	swap128(skb->data, random);
	skb_pull(skb, sizeof(random));

	memset(hcon->ltk, 0, sizeof(hcon->ltk));

	if (conn->hcon->out)
		ret = smp_c1(tfm, conn->tk, random, conn->preq, conn->prsp, 0,
				conn->src, conn->hcon->dst_type, conn->dst,
				res);
	else
		ret = smp_c1(tfm, conn->tk, random, conn->preq, conn->prsp,
				conn->hcon->dst_type, conn->dst, 0, conn->src,
				res);
	if (ret)
		return;

	BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");

	swap128(res, confirm);

	if (memcmp(conn->pcnf, confirm, sizeof(conn->pcnf)) != 0) {
		struct smp_cmd_pairing_fail cp;

		BT_ERR("Pairing failed (confirmation values mismatch)");
		cp.reason = SMP_CONFIRM_FAILED;
		smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(cp), &cp);
		return;
	}

	if (conn->hcon->out) {
		__le16 ediv;
		u8 rand[8];

		smp_s1(tfm, conn->tk, random, conn->prnd, key);
		swap128(key, hcon->ltk);

		memset(rand, 0, sizeof(rand));
		ediv = 0;
		hci_le_start_enc(hcon, ediv, rand, hcon->ltk);
	} else {
		u8 r[16];

		swap128(conn->prnd, r);
		smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(r), r);

		smp_s1(tfm, conn->tk, conn->prnd, random, key);
		swap128(key, hcon->ltk);
	}
}

static void 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;

	BT_DBG("conn %p", conn);

	if (test_bit(HCI_CONN_ENCRYPT_PEND, &hcon->pend))
		return;

	skb_pull(skb, sizeof(*rp));
	memset(&cp, 0, sizeof(cp));

	cp.io_capability = 0x00;
	cp.oob_flag = 0x00;
	cp.max_key_size = 16;
	cp.init_key_dist = 0x00;
	cp.resp_key_dist = 0x00;
	cp.auth_req = rp->auth_req & (SMP_AUTH_BONDING | SMP_AUTH_MITM);

	conn->preq[0] = SMP_CMD_PAIRING_REQ;
	memcpy(&conn->preq[1], &cp, sizeof(cp));

	smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);

	set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->pend);
}

static __u8 seclevel_to_authreq(__u8 level)
{
	switch (level) {
	case BT_SECURITY_HIGH:
		/* For now we don't support bonding */
		return SMP_AUTH_MITM;

	default:
		return SMP_AUTH_NONE;
	}
}

int smp_conn_security(struct l2cap_conn *conn, __u8 sec_level)
{
	struct hci_conn *hcon = conn->hcon;
	__u8 authreq;

	BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level);

	if (IS_ERR(hcon->hdev->tfm))
		return 1;

	if (test_bit(HCI_CONN_ENCRYPT_PEND, &hcon->pend))
		return 0;

	if (sec_level == BT_SECURITY_LOW)
		return 1;

	if (hcon->sec_level >= sec_level)
		return 1;

	authreq = seclevel_to_authreq(sec_level);

	if (hcon->link_mode & HCI_LM_MASTER) {
		struct smp_cmd_pairing cp;
		cp.io_capability = 0x00;
		cp.oob_flag = 0x00;
		cp.max_key_size = 16;
		cp.init_key_dist = 0x00;
		cp.resp_key_dist = 0x00;
		cp.auth_req = authreq;

		conn->preq[0] = SMP_CMD_PAIRING_REQ;
		memcpy(&conn->preq[1], &cp, sizeof(cp));

		smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
	} else {
		struct smp_cmd_security_req cp;
		cp.auth_req = authreq;
		smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp);
	}

	hcon->pending_sec_level = sec_level;
	set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->pend);

	return 0;
}

int smp_sig_channel(struct l2cap_conn *conn, struct sk_buff *skb)
{
	__u8 code = skb->data[0];
	__u8 reason;
	int err = 0;

	if (IS_ERR(conn->hcon->hdev->tfm)) {
		err = PTR_ERR(conn->hcon->hdev->tfm);
		reason = SMP_PAIRING_NOTSUPP;
		goto done;
	}

	skb_pull(skb, sizeof(code));

	switch (code) {
	case SMP_CMD_PAIRING_REQ:
		smp_cmd_pairing_req(conn, skb);
		break;

	case SMP_CMD_PAIRING_FAIL:
		break;

	case SMP_CMD_PAIRING_RSP:
		smp_cmd_pairing_rsp(conn, skb);
		break;

	case SMP_CMD_SECURITY_REQ:
		smp_cmd_security_req(conn, skb);
		break;

	case SMP_CMD_PAIRING_CONFIRM:
		smp_cmd_pairing_confirm(conn, skb);
		break;

	case SMP_CMD_PAIRING_RANDOM:
		smp_cmd_pairing_random(conn, skb);
		break;

	case SMP_CMD_ENCRYPT_INFO:
	case SMP_CMD_MASTER_IDENT:
	case SMP_CMD_IDENT_INFO:
	case SMP_CMD_IDENT_ADDR_INFO:
	case SMP_CMD_SIGN_INFO:
	default:
		BT_DBG("Unknown command code 0x%2.2x", code);

		reason = SMP_CMD_NOTSUPP;
		err = -EOPNOTSUPP;
		goto done;
	}

done:
	if (reason)
		smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason),
								&reason);

	kfree_skb(skb);
	return err;
}
Commit	Line	Data
eb492e01 AB	1	/*
	2	BlueZ - Bluetooth protocol stack for Linux
	3	Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
	4
	5	This program is free software; you can redistribute it and/or modify
	6	it under the terms of the GNU General Public License version 2 as
	7	published by the Free Software Foundation;
	8
	9	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
	10	OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	11	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
	12	IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
	13	CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
	14	WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
	15	ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
	16	OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
	17
	18	ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
	19	COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
	20	SOFTWARE IS DISCLAIMED.
	21	*/
	22
	23	#include <net/bluetooth/bluetooth.h>
	24	#include <net/bluetooth/hci_core.h>
	25	#include <net/bluetooth/l2cap.h>
	26	#include <net/bluetooth/smp.h>
d22ef0bc AB	27	#include <linux/crypto.h>
	28	#include <crypto/b128ops.h>
	29
	30	static inline void swap128(u8 src[16], u8 dst[16])
	31	{
	32	int i;
	33	for (i = 0; i < 16; i++)
	34	dst[15 - i] = src[i];
	35	}
	36
	37	static inline void swap56(u8 src[7], u8 dst[7])
	38	{
	39	int i;
	40	for (i = 0; i < 7; i++)
	41	dst[6 - i] = src[i];
	42	}
	43
	44	static int smp_e(struct crypto_blkcipher tfm, const u8 k, u8 *r)
	45	{
	46	struct blkcipher_desc desc;
	47	struct scatterlist sg;
	48	int err, iv_len;
	49	unsigned char iv[128];
	50
	51	if (tfm == NULL) {
	52	BT_ERR("tfm %p", tfm);
	53	return -EINVAL;
	54	}
	55
	56	desc.tfm = tfm;
	57	desc.flags = 0;
	58
	59	err = crypto_blkcipher_setkey(tfm, k, 16);
	60	if (err) {
	61	BT_ERR("cipher setkey failed: %d", err);
	62	return err;
	63	}
	64
	65	sg_init_one(&sg, r, 16);
	66
	67	iv_len = crypto_blkcipher_ivsize(tfm);
	68	if (iv_len) {
	69	memset(&iv, 0xff, iv_len);
	70	crypto_blkcipher_set_iv(tfm, iv, iv_len);
	71	}
	72
	73	err = crypto_blkcipher_encrypt(&desc, &sg, &sg, 16);
	74	if (err)
	75	BT_ERR("Encrypt data error %d", err);
	76
	77	return err;
	78	}
	79
	80	static int smp_c1(struct crypto_blkcipher *tfm, u8 k[16], u8 r[16],
	81	u8 preq[7], u8 pres[7], u8 _iat, bdaddr_t *ia,
	82	u8 _rat, bdaddr_t *ra, u8 res[16])
	83	{
	84	u8 p1[16], p2[16];
	85	int err;
	86
	87	memset(p1, 0, 16);
	88
	89	/* p1 = pres \|\| preq \|\| _rat \|\| _iat */
	90	swap56(pres, p1);
91	swap56(preq, p1 + 7);
92	p1[14] = _rat;
93	p1[15] = _iat;
94
95	memset(p2, 0, 16);
96
97	/* p2 = padding \|\| ia \|\| ra */
98	baswap((bdaddr_t *) (p2 + 4), ia);
99	baswap((bdaddr_t *) (p2 + 10), ra);
100
101	/* res = r XOR p1 */
102	u128_xor((u128 ) res, (u128 ) r, (u128 *) p1);
103
104	/* res = e(k, res) */
105	err = smp_e(tfm, k, res);
106	if (err) {
107	BT_ERR("Encrypt data error");
108	return err;
109	}
110
111	/* res = res XOR p2 */
112	u128_xor((u128 ) res, (u128 ) res, (u128 *) p2);
113
114	/* res = e(k, res) */
115	err = smp_e(tfm, k, res);
116	if (err)
117	BT_ERR("Encrypt data error");
118
119	return err;
120	}
121
122	static int smp_s1(struct crypto_blkcipher *tfm, u8 k[16],
123	u8 r1[16], u8 r2[16], u8 _r[16])
124	{
125	int err;
126
127	/* Just least significant octets from r1 and r2 are considered */
128	memcpy(_r, r1 + 8, 8);
129	memcpy(_r + 8, r2 + 8, 8);
130
131	err = smp_e(tfm, k, _r);
132	if (err)
133	BT_ERR("Encrypt data error");
134
135	return err;
136	}
137
138	static int smp_rand(u8 *buf)
139	{
140	get_random_bytes(buf, 16);
141
142	return 0;
143	}
eb492e01 AB	144
	145	static struct sk_buff smp_build_cmd(struct l2cap_conn conn, u8 code,
	146	u16 dlen, void *data)
	147	{
	148	struct sk_buff *skb;
	149	struct l2cap_hdr *lh;
	150	int len;
	151
	152	len = L2CAP_HDR_SIZE + sizeof(code) + dlen;
	153
	154	if (len > conn->mtu)
	155	return NULL;
	156
	157	skb = bt_skb_alloc(len, GFP_ATOMIC);
	158	if (!skb)
	159	return NULL;
	160
	161	lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
	162	lh->len = cpu_to_le16(sizeof(code) + dlen);
	163	lh->cid = cpu_to_le16(L2CAP_CID_SMP);
	164
	165	memcpy(skb_put(skb, sizeof(code)), &code, sizeof(code));
	166
	167	memcpy(skb_put(skb, dlen), data, dlen);
	168
	169	return skb;
	170	}
	171
	172	static void smp_send_cmd(struct l2cap_conn conn, u8 code, u16 len, void data)
	173	{
	174	struct sk_buff *skb = smp_build_cmd(conn, code, len, data);
	175
	176	BT_DBG("code 0x%2.2x", code);
	177
	178	if (!skb)
	179	return;
	180
	181	hci_send_acl(conn->hcon, skb, 0);
	182	}
	183
b8e66eac VCG	184	static void build_pairing_cmd(struct l2cap_conn *conn,
	185	struct smp_cmd_pairing *cmd, __u8 authreq)
	186	{
	187	cmd->io_capability = conn->hcon->io_capability;
	188	cmd->oob_flag = SMP_OOB_NOT_PRESENT;
	189	cmd->max_key_size = 16;
	190	cmd->init_key_dist = 0x00;
	191	cmd->resp_key_dist = 0x00;
	192	cmd->auth_req = authreq;
	193	}
	194
88ba43b6 AB	195	static void smp_cmd_pairing_req(struct l2cap_conn conn, struct sk_buff skb)
	196	{
	197	struct smp_cmd_pairing rp = (void ) skb->data;
	198
	199	BT_DBG("conn %p", conn);
	200
f01ead31 AB	201	conn->preq[0] = SMP_CMD_PAIRING_REQ;
f01ead31 AB	202	memcpy(&conn->preq[1], rp, sizeof(*rp));
88ba43b6 AB	203	skb_pull(skb, sizeof(*rp));
	204
	205	rp->io_capability = 0x00;
	206	rp->oob_flag = 0x00;
	207	rp->max_key_size = 16;
	208	rp->init_key_dist = 0x00;
	209	rp->resp_key_dist = 0x00;
	210	rp->auth_req &= (SMP_AUTH_BONDING \| SMP_AUTH_MITM);
	211
7d24ddcc AB	212	/* Just works */
	213	memset(conn->tk, 0, sizeof(conn->tk));
	214
f01ead31 AB	215	conn->prsp[0] = SMP_CMD_PAIRING_RSP;
	216	memcpy(&conn->prsp[1], rp, sizeof(*rp));
	217
88ba43b6 AB	218	smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(*rp), rp);
	219	}
	220
	221	static void smp_cmd_pairing_rsp(struct l2cap_conn conn, struct sk_buff skb)
	222	{
f01ead31	223	struct smp_cmd_pairing rp = (void ) skb->data;
88ba43b6	224	struct smp_cmd_pairing_confirm cp;
7d24ddcc AB	225	struct crypto_blkcipher *tfm = conn->hcon->hdev->tfm;
	226	int ret;
	227	u8 res[16];
88ba43b6 AB	228
	229	BT_DBG("conn %p", conn);
	230
7d24ddcc AB	231	/* Just works */
7d24ddcc AB	232	memset(conn->tk, 0, sizeof(conn->tk));
88ba43b6	233
f01ead31 AB	234	conn->prsp[0] = SMP_CMD_PAIRING_RSP;
	235	memcpy(&conn->prsp[1], rp, sizeof(*rp));
	236	skb_pull(skb, sizeof(*rp));
	237
7d24ddcc AB	238	ret = smp_rand(conn->prnd);
	239	if (ret)
	240	return;
	241
	242	ret = smp_c1(tfm, conn->tk, conn->prnd, conn->preq, conn->prsp, 0,
	243	conn->src, conn->hcon->dst_type, conn->dst, res);
	244	if (ret)
	245	return;
	246
	247	swap128(res, cp.confirm_val);
	248
88ba43b6 AB	249	smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
	250	}
	251
	252	static void smp_cmd_pairing_confirm(struct l2cap_conn *conn,
	253	struct sk_buff *skb)
	254	{
7d24ddcc AB	255	struct crypto_blkcipher *tfm = conn->hcon->hdev->tfm;
7d24ddcc AB	256
88ba43b6 AB	257	BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
88ba43b6 AB	258
7d24ddcc AB	259	memcpy(conn->pcnf, skb->data, sizeof(conn->pcnf));
7d24ddcc AB	260	skb_pull(skb, sizeof(conn->pcnf));
88ba43b6	261
7d24ddcc AB	262	if (conn->hcon->out) {
7d24ddcc AB	263	u8 random[16];
88ba43b6	264
7d24ddcc	265	swap128(conn->prnd, random);
88ba43b6	266	smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(random),
7d24ddcc	267	random);
88ba43b6	268	} else {
7d24ddcc AB	269	struct smp_cmd_pairing_confirm cp;
	270	int ret;
	271	u8 res[16];
88ba43b6	272
7d24ddcc AB	273	ret = smp_rand(conn->prnd);
	274	if (ret)
	275	return;
88ba43b6	276
7d24ddcc AB	277	ret = smp_c1(tfm, conn->tk, conn->prnd, conn->preq, conn->prsp,
	278	conn->hcon->dst_type, conn->dst,
	279	0, conn->src, res);
	280	if (ret)
	281	return;
	282
	283	swap128(res, cp.confirm_val);
	284
	285	smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
88ba43b6 AB	286	}
	287	}
	288
	289	static void smp_cmd_pairing_random(struct l2cap_conn conn, struct sk_buff skb)
	290	{
a7a595f6 VCG	291	struct hci_conn *hcon = conn->hcon;
a7a595f6 VCG	292	struct crypto_blkcipher *tfm = hcon->hdev->tfm;
7d24ddcc	293	int ret;
9b3d6740	294	u8 key[16], res[16], random[16], confirm[16];
7d24ddcc AB	295
	296	swap128(skb->data, random);
	297	skb_pull(skb, sizeof(random));
	298
a7a595f6 VCG	299	memset(hcon->ltk, 0, sizeof(hcon->ltk));
a7a595f6 VCG	300
7d24ddcc AB	301	if (conn->hcon->out)
	302	ret = smp_c1(tfm, conn->tk, random, conn->preq, conn->prsp, 0,
	303	conn->src, conn->hcon->dst_type, conn->dst,
	304	res);
	305	else
	306	ret = smp_c1(tfm, conn->tk, random, conn->preq, conn->prsp,
	307	conn->hcon->dst_type, conn->dst, 0, conn->src,
	308	res);
	309	if (ret)
	310	return;
88ba43b6 AB	311
	312	BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
	313
7d24ddcc AB	314	swap128(res, confirm);
	315
	316	if (memcmp(conn->pcnf, confirm, sizeof(conn->pcnf)) != 0) {
	317	struct smp_cmd_pairing_fail cp;
	318
	319	BT_ERR("Pairing failed (confirmation values mismatch)");
	320	cp.reason = SMP_CONFIRM_FAILED;
	321	smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(cp), &cp);
	322	return;
	323	}
88ba43b6 AB	324
88ba43b6 AB	325	if (conn->hcon->out) {
a7a595f6 VCG	326	__le16 ediv;
	327	u8 rand[8];
	328
7d24ddcc	329	smp_s1(tfm, conn->tk, random, conn->prnd, key);
a7a595f6	330	swap128(key, hcon->ltk);
7d24ddcc	331
a7a595f6 VCG	332	memset(rand, 0, sizeof(rand));
	333	ediv = 0;
	334	hci_le_start_enc(hcon, ediv, rand, hcon->ltk);
88ba43b6	335	} else {
7d24ddcc AB	336	u8 r[16];
	337
	338	swap128(conn->prnd, r);
	339	smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(r), r);
	340
	341	smp_s1(tfm, conn->tk, conn->prnd, random, key);
a7a595f6	342	swap128(key, hcon->ltk);
88ba43b6 AB	343	}
	344	}
	345
	346	static void smp_cmd_security_req(struct l2cap_conn conn, struct sk_buff skb)
	347	{
	348	struct smp_cmd_security_req rp = (void ) skb->data;
	349	struct smp_cmd_pairing cp;
f1cb9af5	350	struct hci_conn *hcon = conn->hcon;
88ba43b6 AB	351
	352	BT_DBG("conn %p", conn);
	353
f1cb9af5 VCG	354	if (test_bit(HCI_CONN_ENCRYPT_PEND, &hcon->pend))
	355	return;
	356
88ba43b6 AB	357	skb_pull(skb, sizeof(*rp));
	358	memset(&cp, 0, sizeof(cp));
	359
	360	cp.io_capability = 0x00;
	361	cp.oob_flag = 0x00;
	362	cp.max_key_size = 16;
	363	cp.init_key_dist = 0x00;
	364	cp.resp_key_dist = 0x00;
	365	cp.auth_req = rp->auth_req & (SMP_AUTH_BONDING \| SMP_AUTH_MITM);
	366
f01ead31 AB	367	conn->preq[0] = SMP_CMD_PAIRING_REQ;
	368	memcpy(&conn->preq[1], &cp, sizeof(cp));
	369
88ba43b6	370	smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
f1cb9af5 VCG	371
	372	set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->pend);
	373	}
	374
	375	static __u8 seclevel_to_authreq(__u8 level)
	376	{
	377	switch (level) {
	378	case BT_SECURITY_HIGH:
	379	/* For now we don't support bonding */
	380	return SMP_AUTH_MITM;
	381
	382	default:
	383	return SMP_AUTH_NONE;
	384	}
88ba43b6 AB	385	}
88ba43b6 AB	386
eb492e01 AB	387	int smp_conn_security(struct l2cap_conn *conn, __u8 sec_level)
eb492e01 AB	388	{
3a0259bb	389	struct hci_conn *hcon = conn->hcon;
eb492e01 AB	390	__u8 authreq;
eb492e01 AB	391
3a0259bb VCG	392	BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level);
	393
	394	if (IS_ERR(hcon->hdev->tfm))
	395	return 1;
eb492e01	396
f1cb9af5 VCG	397	if (test_bit(HCI_CONN_ENCRYPT_PEND, &hcon->pend))
f1cb9af5 VCG	398	return 0;
eb492e01	399
f1cb9af5 VCG	400	if (sec_level == BT_SECURITY_LOW)
f1cb9af5 VCG	401	return 1;
eb492e01	402
f1cb9af5	403	if (hcon->sec_level >= sec_level)
eb492e01	404	return 1;
f1cb9af5 VCG	405
f1cb9af5 VCG	406	authreq = seclevel_to_authreq(sec_level);
eb492e01	407
3a0259bb	408	if (hcon->link_mode & HCI_LM_MASTER) {
eb492e01 AB	409	struct smp_cmd_pairing cp;
	410	cp.io_capability = 0x00;
	411	cp.oob_flag = 0x00;
	412	cp.max_key_size = 16;
	413	cp.init_key_dist = 0x00;
	414	cp.resp_key_dist = 0x00;
	415	cp.auth_req = authreq;
f01ead31 AB	416
	417	conn->preq[0] = SMP_CMD_PAIRING_REQ;
	418	memcpy(&conn->preq[1], &cp, sizeof(cp));
	419
eb492e01 AB	420	smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
	421	} else {
	422	struct smp_cmd_security_req cp;
	423	cp.auth_req = authreq;
	424	smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp);
	425	}
	426
f1cb9af5 VCG	427	hcon->pending_sec_level = sec_level;
	428	set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->pend);
	429
eb492e01 AB	430	return 0;
	431	}
	432
	433	int smp_sig_channel(struct l2cap_conn conn, struct sk_buff skb)
	434	{
	435	__u8 code = skb->data[0];
	436	__u8 reason;
	437	int err = 0;
	438
3a0259bb VCG	439	if (IS_ERR(conn->hcon->hdev->tfm)) {
	440	err = PTR_ERR(conn->hcon->hdev->tfm);
	441	reason = SMP_PAIRING_NOTSUPP;
	442	goto done;
	443	}
	444
eb492e01 AB	445	skb_pull(skb, sizeof(code));
	446
	447	switch (code) {
	448	case SMP_CMD_PAIRING_REQ:
88ba43b6	449	smp_cmd_pairing_req(conn, skb);
eb492e01 AB	450	break;
	451
	452	case SMP_CMD_PAIRING_FAIL:
	453	break;
	454
	455	case SMP_CMD_PAIRING_RSP:
88ba43b6 AB	456	smp_cmd_pairing_rsp(conn, skb);
	457	break;
	458
	459	case SMP_CMD_SECURITY_REQ:
	460	smp_cmd_security_req(conn, skb);
	461	break;
	462
eb492e01	463	case SMP_CMD_PAIRING_CONFIRM:
88ba43b6 AB	464	smp_cmd_pairing_confirm(conn, skb);
	465	break;
	466
eb492e01	467	case SMP_CMD_PAIRING_RANDOM:
88ba43b6 AB	468	smp_cmd_pairing_random(conn, skb);
	469	break;
	470
eb492e01 AB	471	case SMP_CMD_ENCRYPT_INFO:
	472	case SMP_CMD_MASTER_IDENT:
	473	case SMP_CMD_IDENT_INFO:
	474	case SMP_CMD_IDENT_ADDR_INFO:
	475	case SMP_CMD_SIGN_INFO:
eb492e01 AB	476	default:
	477	BT_DBG("Unknown command code 0x%2.2x", code);
	478
	479	reason = SMP_CMD_NOTSUPP;
eb492e01	480	err = -EOPNOTSUPP;
3a0259bb	481	goto done;
eb492e01 AB	482	}
eb492e01 AB	483
3a0259bb VCG	484	done:
	485	if (reason)
	486	smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason),
	487	&reason);
	488
eb492e01 AB	489	kfree_skb(skb);
	490	return err;
	491	}