[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 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
88ba43b6 AB	184	static void smp_cmd_pairing_req(struct l2cap_conn conn, struct sk_buff skb)
	185	{
	186	struct smp_cmd_pairing rp = (void ) skb->data;
	187
	188	BT_DBG("conn %p", conn);
	189
f01ead31 AB	190	conn->preq[0] = SMP_CMD_PAIRING_REQ;
f01ead31 AB	191	memcpy(&conn->preq[1], rp, sizeof(*rp));
88ba43b6 AB	192	skb_pull(skb, sizeof(*rp));
	193
	194	rp->io_capability = 0x00;
	195	rp->oob_flag = 0x00;
	196	rp->max_key_size = 16;
	197	rp->init_key_dist = 0x00;
	198	rp->resp_key_dist = 0x00;
	199	rp->auth_req &= (SMP_AUTH_BONDING \| SMP_AUTH_MITM);
	200
7d24ddcc AB	201	/* Just works */
	202	memset(conn->tk, 0, sizeof(conn->tk));
	203
f01ead31 AB	204	conn->prsp[0] = SMP_CMD_PAIRING_RSP;
	205	memcpy(&conn->prsp[1], rp, sizeof(*rp));
	206
88ba43b6 AB	207	smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(*rp), rp);
	208	}
	209
	210	static void smp_cmd_pairing_rsp(struct l2cap_conn conn, struct sk_buff skb)
	211	{
f01ead31	212	struct smp_cmd_pairing rp = (void ) skb->data;
88ba43b6	213	struct smp_cmd_pairing_confirm cp;
7d24ddcc AB	214	struct crypto_blkcipher *tfm = conn->hcon->hdev->tfm;
	215	int ret;
	216	u8 res[16];
88ba43b6 AB	217
	218	BT_DBG("conn %p", conn);
	219
7d24ddcc AB	220	/* Just works */
7d24ddcc AB	221	memset(conn->tk, 0, sizeof(conn->tk));
88ba43b6	222
f01ead31 AB	223	conn->prsp[0] = SMP_CMD_PAIRING_RSP;
	224	memcpy(&conn->prsp[1], rp, sizeof(*rp));
	225	skb_pull(skb, sizeof(*rp));
	226
7d24ddcc AB	227	ret = smp_rand(conn->prnd);
	228	if (ret)
	229	return;
	230
	231	ret = smp_c1(tfm, conn->tk, conn->prnd, conn->preq, conn->prsp, 0,
	232	conn->src, conn->hcon->dst_type, conn->dst, res);
	233	if (ret)
	234	return;
	235
	236	swap128(res, cp.confirm_val);
	237
88ba43b6 AB	238	smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
	239	}
	240
	241	static void smp_cmd_pairing_confirm(struct l2cap_conn *conn,
	242	struct sk_buff *skb)
	243	{
7d24ddcc AB	244	struct crypto_blkcipher *tfm = conn->hcon->hdev->tfm;
7d24ddcc AB	245
88ba43b6 AB	246	BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
88ba43b6 AB	247
7d24ddcc AB	248	memcpy(conn->pcnf, skb->data, sizeof(conn->pcnf));
7d24ddcc AB	249	skb_pull(skb, sizeof(conn->pcnf));
88ba43b6	250
7d24ddcc AB	251	if (conn->hcon->out) {
7d24ddcc AB	252	u8 random[16];
88ba43b6	253
7d24ddcc	254	swap128(conn->prnd, random);
88ba43b6	255	smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(random),
7d24ddcc	256	random);
88ba43b6	257	} else {
7d24ddcc AB	258	struct smp_cmd_pairing_confirm cp;
	259	int ret;
	260	u8 res[16];
88ba43b6	261
7d24ddcc AB	262	ret = smp_rand(conn->prnd);
	263	if (ret)
	264	return;
88ba43b6	265
7d24ddcc AB	266	ret = smp_c1(tfm, conn->tk, conn->prnd, conn->preq, conn->prsp,
	267	conn->hcon->dst_type, conn->dst,
	268	0, conn->src, res);
	269	if (ret)
	270	return;
	271
	272	swap128(res, cp.confirm_val);
	273
	274	smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
88ba43b6 AB	275	}
	276	}
	277
	278	static void smp_cmd_pairing_random(struct l2cap_conn conn, struct sk_buff skb)
	279	{
a7a595f6 VCG	280	struct hci_conn *hcon = conn->hcon;
a7a595f6 VCG	281	struct crypto_blkcipher *tfm = hcon->hdev->tfm;
7d24ddcc	282	int ret;
9b3d6740	283	u8 key[16], res[16], random[16], confirm[16];
7d24ddcc AB	284
	285	swap128(skb->data, random);
	286	skb_pull(skb, sizeof(random));
	287
a7a595f6 VCG	288	memset(hcon->ltk, 0, sizeof(hcon->ltk));
a7a595f6 VCG	289
7d24ddcc AB	290	if (conn->hcon->out)
	291	ret = smp_c1(tfm, conn->tk, random, conn->preq, conn->prsp, 0,
	292	conn->src, conn->hcon->dst_type, conn->dst,
	293	res);
	294	else
	295	ret = smp_c1(tfm, conn->tk, random, conn->preq, conn->prsp,
	296	conn->hcon->dst_type, conn->dst, 0, conn->src,
	297	res);
	298	if (ret)
	299	return;
88ba43b6 AB	300
	301	BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
	302
7d24ddcc AB	303	swap128(res, confirm);
	304
	305	if (memcmp(conn->pcnf, confirm, sizeof(conn->pcnf)) != 0) {
	306	struct smp_cmd_pairing_fail cp;
	307
	308	BT_ERR("Pairing failed (confirmation values mismatch)");
	309	cp.reason = SMP_CONFIRM_FAILED;
	310	smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(cp), &cp);
	311	return;
	312	}
88ba43b6 AB	313
88ba43b6 AB	314	if (conn->hcon->out) {
a7a595f6 VCG	315	__le16 ediv;
	316	u8 rand[8];
	317
7d24ddcc	318	smp_s1(tfm, conn->tk, random, conn->prnd, key);
a7a595f6	319	swap128(key, hcon->ltk);
7d24ddcc	320
a7a595f6 VCG	321	memset(rand, 0, sizeof(rand));
	322	ediv = 0;
	323	hci_le_start_enc(hcon, ediv, rand, hcon->ltk);
88ba43b6	324	} else {
7d24ddcc AB	325	u8 r[16];
	326
	327	swap128(conn->prnd, r);
	328	smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(r), r);
	329
	330	smp_s1(tfm, conn->tk, conn->prnd, random, key);
a7a595f6	331	swap128(key, hcon->ltk);
88ba43b6 AB	332	}
	333	}
	334
	335	static void smp_cmd_security_req(struct l2cap_conn conn, struct sk_buff skb)
	336	{
	337	struct smp_cmd_security_req rp = (void ) skb->data;
	338	struct smp_cmd_pairing cp;
f1cb9af5	339	struct hci_conn *hcon = conn->hcon;
88ba43b6 AB	340
	341	BT_DBG("conn %p", conn);
	342
f1cb9af5 VCG	343	if (test_bit(HCI_CONN_ENCRYPT_PEND, &hcon->pend))
	344	return;
	345
88ba43b6 AB	346	skb_pull(skb, sizeof(*rp));
	347	memset(&cp, 0, sizeof(cp));
	348
	349	cp.io_capability = 0x00;
	350	cp.oob_flag = 0x00;
	351	cp.max_key_size = 16;
	352	cp.init_key_dist = 0x00;
	353	cp.resp_key_dist = 0x00;
	354	cp.auth_req = rp->auth_req & (SMP_AUTH_BONDING \| SMP_AUTH_MITM);
	355
f01ead31 AB	356	conn->preq[0] = SMP_CMD_PAIRING_REQ;
	357	memcpy(&conn->preq[1], &cp, sizeof(cp));
	358
88ba43b6	359	smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
f1cb9af5 VCG	360
	361	set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->pend);
	362	}
	363
	364	static __u8 seclevel_to_authreq(__u8 level)
	365	{
	366	switch (level) {
	367	case BT_SECURITY_HIGH:
	368	/* For now we don't support bonding */
	369	return SMP_AUTH_MITM;
	370
	371	default:
	372	return SMP_AUTH_NONE;
	373	}
88ba43b6 AB	374	}
88ba43b6 AB	375
eb492e01 AB	376	int smp_conn_security(struct l2cap_conn *conn, __u8 sec_level)
eb492e01 AB	377	{
3a0259bb	378	struct hci_conn *hcon = conn->hcon;
eb492e01 AB	379	__u8 authreq;
eb492e01 AB	380
3a0259bb VCG	381	BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level);
	382
	383	if (IS_ERR(hcon->hdev->tfm))
	384	return 1;
eb492e01	385
f1cb9af5 VCG	386	if (test_bit(HCI_CONN_ENCRYPT_PEND, &hcon->pend))
f1cb9af5 VCG	387	return 0;
eb492e01	388
f1cb9af5 VCG	389	if (sec_level == BT_SECURITY_LOW)
f1cb9af5 VCG	390	return 1;
eb492e01	391
f1cb9af5	392	if (hcon->sec_level >= sec_level)
eb492e01	393	return 1;
f1cb9af5 VCG	394
f1cb9af5 VCG	395	authreq = seclevel_to_authreq(sec_level);
eb492e01	396
3a0259bb	397	if (hcon->link_mode & HCI_LM_MASTER) {
eb492e01 AB	398	struct smp_cmd_pairing cp;
	399	cp.io_capability = 0x00;
	400	cp.oob_flag = 0x00;
	401	cp.max_key_size = 16;
	402	cp.init_key_dist = 0x00;
	403	cp.resp_key_dist = 0x00;
	404	cp.auth_req = authreq;
f01ead31 AB	405
	406	conn->preq[0] = SMP_CMD_PAIRING_REQ;
	407	memcpy(&conn->preq[1], &cp, sizeof(cp));
	408
eb492e01 AB	409	smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
	410	} else {
	411	struct smp_cmd_security_req cp;
	412	cp.auth_req = authreq;
	413	smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp);
	414	}
	415
f1cb9af5 VCG	416	hcon->pending_sec_level = sec_level;
	417	set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->pend);
	418
eb492e01 AB	419	return 0;
	420	}
	421
	422	int smp_sig_channel(struct l2cap_conn conn, struct sk_buff skb)
	423	{
	424	__u8 code = skb->data[0];
	425	__u8 reason;
	426	int err = 0;
	427
3a0259bb VCG	428	if (IS_ERR(conn->hcon->hdev->tfm)) {
	429	err = PTR_ERR(conn->hcon->hdev->tfm);
	430	reason = SMP_PAIRING_NOTSUPP;
	431	goto done;
	432	}
	433
eb492e01 AB	434	skb_pull(skb, sizeof(code));
	435
	436	switch (code) {
	437	case SMP_CMD_PAIRING_REQ:
88ba43b6	438	smp_cmd_pairing_req(conn, skb);
eb492e01 AB	439	break;
	440
	441	case SMP_CMD_PAIRING_FAIL:
	442	break;
	443
	444	case SMP_CMD_PAIRING_RSP:
88ba43b6 AB	445	smp_cmd_pairing_rsp(conn, skb);
	446	break;
	447
	448	case SMP_CMD_SECURITY_REQ:
	449	smp_cmd_security_req(conn, skb);
	450	break;
	451
eb492e01	452	case SMP_CMD_PAIRING_CONFIRM:
88ba43b6 AB	453	smp_cmd_pairing_confirm(conn, skb);
	454	break;
	455
eb492e01	456	case SMP_CMD_PAIRING_RANDOM:
88ba43b6 AB	457	smp_cmd_pairing_random(conn, skb);
	458	break;
	459
eb492e01 AB	460	case SMP_CMD_ENCRYPT_INFO:
	461	case SMP_CMD_MASTER_IDENT:
	462	case SMP_CMD_IDENT_INFO:
	463	case SMP_CMD_IDENT_ADDR_INFO:
	464	case SMP_CMD_SIGN_INFO:
eb492e01 AB	465	default:
	466	BT_DBG("Unknown command code 0x%2.2x", code);
	467
	468	reason = SMP_CMD_NOTSUPP;
eb492e01	469	err = -EOPNOTSUPP;
3a0259bb	470	goto done;
eb492e01 AB	471	}
eb492e01 AB	472
3a0259bb VCG	473	done:
	474	if (reason)
	475	smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason),
	476	&reason);
	477
eb492e01 AB	478	kfree_skb(skb);
	479	return err;
	480	}