summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
Diffstat
-rw-r--r--net/bluetooth/ecdh_helper.c186
-rw-r--r--net/bluetooth/ecdh_helper.h9
-rw-r--r--net/bluetooth/selftest.c14
-rw-r--r--net/bluetooth/smp.c66
4 files changed, 147 insertions, 128 deletions
diff --git a/net/bluetooth/ecdh_helper.c b/net/bluetooth/ecdh_helper.c
index 16e022f5ab27..2155ce802877 100644
--- a/net/bluetooth/ecdh_helper.c
+++ b/net/bluetooth/ecdh_helper.c
@@ -49,15 +49,21 @@ static inline void swap_digits(u64 *in, u64 *out, unsigned int ndigits)
out[i] = __swab64(in[ndigits - 1 - i]);
}
+/* compute_ecdh_secret() - function assumes that the private key was
+ * already set.
+ * @tfm: KPP tfm handle allocated with crypto_alloc_kpp().
+ * @public_key: pair's ecc public key.
+ * secret: memory where the ecdh computed shared secret will be saved.
+ *
+ * Return: zero on success; error code in case of error.
+ */
int compute_ecdh_secret(struct crypto_kpp *tfm, const u8 public_key[64],
- const u8 private_key[32], u8 secret[32])
+ u8 secret[32])
{
struct kpp_request *req;
- struct ecdh p;
+ u8 *tmp;
struct ecdh_completion result;
struct scatterlist src, dst;
- u8 *tmp, *buf;
- unsigned int buf_len;
int err;
tmp = kmalloc(64, GFP_KERNEL);
@@ -72,28 +78,6 @@ int compute_ecdh_secret(struct crypto_kpp *tfm, const u8 public_key[64],
init_completion(&result.completion);
- /* Security Manager Protocol holds digits in litte-endian order
- * while ECC API expect big-endian data
- */
- swap_digits((u64 *)private_key, (u64 *)tmp, 4);
- p.key = (char *)tmp;
- p.key_size = 32;
- /* Set curve_id */
- p.curve_id = ECC_CURVE_NIST_P256;
- buf_len = crypto_ecdh_key_len(&p);
- buf = kmalloc(buf_len, GFP_KERNEL);
- if (!buf) {
- err = -ENOMEM;
- goto free_req;
- }
-
- crypto_ecdh_encode_key(buf, buf_len, &p);
-
- /* Set A private Key */
- err = crypto_kpp_set_secret(tfm, (void *)buf, buf_len);
- if (err)
- goto free_all;
-
swap_digits((u64 *)public_key, (u64 *)tmp, 4); /* x */
swap_digits((u64 *)&public_key[32], (u64 *)&tmp[32], 4); /* y */
@@ -118,26 +102,76 @@ int compute_ecdh_secret(struct crypto_kpp *tfm, const u8 public_key[64],
memcpy(secret, tmp, 32);
free_all:
- kzfree(buf);
-free_req:
kpp_request_free(req);
free_tmp:
kzfree(tmp);
return err;
}
-int generate_ecdh_keys(struct crypto_kpp *tfm, u8 public_key[64],
- u8 private_key[32])
+/* set_ecdh_privkey() - set or generate ecc private key.
+ *
+ * Function generates an ecc private key in the crypto subsystem when receiving
+ * a NULL private key or sets the received key when not NULL.
+ *
+ * @tfm: KPP tfm handle allocated with crypto_alloc_kpp().
+ * @private_key: user's ecc private key. When not NULL, the key is expected
+ * in little endian format.
+ *
+ * Return: zero on success; error code in case of error.
+ */
+int set_ecdh_privkey(struct crypto_kpp *tfm, const u8 private_key[32])
+{
+ u8 *buf, *tmp = NULL;
+ unsigned int buf_len;
+ int err;
+ struct ecdh p = {0};
+
+ p.curve_id = ECC_CURVE_NIST_P256;
+
+ if (private_key) {
+ tmp = kmalloc(32, GFP_KERNEL);
+ if (!tmp)
+ return -ENOMEM;
+ swap_digits((u64 *)private_key, (u64 *)tmp, 4);
+ p.key = tmp;
+ p.key_size = 32;
+ }
+
+ buf_len = crypto_ecdh_key_len(&p);
+ buf = kmalloc(buf_len, GFP_KERNEL);
+ if (!buf) {
+ err = -ENOMEM;
+ goto free_tmp;
+ }
+
+ err = crypto_ecdh_encode_key(buf, buf_len, &p);
+ if (err)
+ goto free_all;
+
+ err = crypto_kpp_set_secret(tfm, buf, buf_len);
+ /* fall through */
+free_all:
+ kzfree(buf);
+free_tmp:
+ kzfree(tmp);
+ return err;
+}
+
+/* generate_ecdh_public_key() - function assumes that the private key was
+ * already set.
+ *
+ * @tfm: KPP tfm handle allocated with crypto_alloc_kpp().
+ * @public_key: memory where the computed ecc public key will be saved.
+ *
+ * Return: zero on success; error code in case of error.
+ */
+int generate_ecdh_public_key(struct crypto_kpp *tfm, u8 public_key[64])
{
struct kpp_request *req;
- struct ecdh p;
+ u8 *tmp;
struct ecdh_completion result;
struct scatterlist dst;
- u8 *tmp, *buf;
- unsigned int buf_len;
int err;
- const unsigned short max_tries = 16;
- unsigned short tries = 0;
tmp = kmalloc(64, GFP_KERNEL);
if (!tmp)
@@ -150,63 +184,47 @@ int generate_ecdh_keys(struct crypto_kpp *tfm, u8 public_key[64],
}
init_completion(&result.completion);
+ sg_init_one(&dst, tmp, 64);
+ kpp_request_set_input(req, NULL, 0);
+ kpp_request_set_output(req, &dst, 64);
+ kpp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
+ ecdh_complete, &result);
- /* Set curve_id */
- p.curve_id = ECC_CURVE_NIST_P256;
- p.key_size = 32;
- buf_len = crypto_ecdh_key_len(&p);
- buf = kmalloc(buf_len, GFP_KERNEL);
- if (!buf)
- goto free_req;
-
- do {
- if (tries++ >= max_tries)
- goto free_all;
-
- /* Set private Key */
- p.key = (char *)private_key;
- crypto_ecdh_encode_key(buf, buf_len, &p);
- err = crypto_kpp_set_secret(tfm, buf, buf_len);
- if (err)
- goto free_all;
-
- sg_init_one(&dst, tmp, 64);
- kpp_request_set_input(req, NULL, 0);
- kpp_request_set_output(req, &dst, 64);
- kpp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
- ecdh_complete, &result);
-
- err = crypto_kpp_generate_public_key(req);
-
- if (err == -EINPROGRESS) {
- wait_for_completion(&result.completion);
- err = result.err;
- }
-
- /* Private key is not valid. Regenerate */
- if (err == -EINVAL)
- continue;
-
- if (err < 0)
- goto free_all;
- else
- break;
-
- } while (true);
-
- /* Keys are handed back in little endian as expected by Security
- * Manager Protocol
+ err = crypto_kpp_generate_public_key(req);
+ if (err == -EINPROGRESS) {
+ wait_for_completion(&result.completion);
+ err = result.err;
+ }
+ if (err < 0)
+ goto free_all;
+
+ /* The public key is handed back in little endian as expected by
+ * the Security Manager Protocol.
*/
swap_digits((u64 *)tmp, (u64 *)public_key, 4); /* x */
swap_digits((u64 *)&tmp[32], (u64 *)&public_key[32], 4); /* y */
- swap_digits((u64 *)private_key, (u64 *)tmp, 4);
- memcpy(private_key, tmp, 32);
free_all:
- kzfree(buf);
-free_req:
kpp_request_free(req);
free_tmp:
kfree(tmp);
return err;
}
+
+/* generate_ecdh_keys() - generate ecc key pair.
+ *
+ * @tfm: KPP tfm handle allocated with crypto_alloc_kpp().
+ * @public_key: memory where the computed ecc public key will be saved.
+ *
+ * Return: zero on success; error code in case of error.
+ */
+int generate_ecdh_keys(struct crypto_kpp *tfm, u8 public_key[64])
+{
+ int err;
+
+ err = set_ecdh_privkey(tfm, NULL);
+ if (err)
+ return err;
+
+ return generate_ecdh_public_key(tfm, public_key);
+}
diff --git a/net/bluetooth/ecdh_helper.h b/net/bluetooth/ecdh_helper.h
index 50e6676aebf5..a6f8d03d4aaf 100644
--- a/net/bluetooth/ecdh_helper.h
+++ b/net/bluetooth/ecdh_helper.h
@@ -23,7 +23,8 @@
#include <crypto/kpp.h>
#include <linux/types.h>
-int compute_ecdh_secret(struct crypto_kpp *tfm, const u8 pub_a[64],
- const u8 priv_b[32], u8 secret[32]);
-int generate_ecdh_keys(struct crypto_kpp *tfm, u8 public_key[64],
- u8 private_key[32]);
+int compute_ecdh_secret(struct crypto_kpp *tfm, const u8 pair_public_key[64],
+ u8 secret[32]);
+int set_ecdh_privkey(struct crypto_kpp *tfm, const u8 *private_key);
+int generate_ecdh_public_key(struct crypto_kpp *tfm, u8 public_key[64]);
+int generate_ecdh_keys(struct crypto_kpp *tfm, u8 public_key[64]);
diff --git a/net/bluetooth/selftest.c b/net/bluetooth/selftest.c
index ce99648ed870..2d1519d0affa 100644
--- a/net/bluetooth/selftest.c
+++ b/net/bluetooth/selftest.c
@@ -152,11 +152,11 @@ static int __init test_ecdh_sample(struct crypto_kpp *tfm, const u8 priv_a[32],
dhkey_a = &tmp[0];
dhkey_b = &tmp[32];
- ret = compute_ecdh_secret(tfm, pub_b, priv_a, dhkey_a);
+ ret = set_ecdh_privkey(tfm, priv_a);
if (ret)
goto out;
- ret = compute_ecdh_secret(tfm, pub_a, priv_b, dhkey_b);
+ ret = compute_ecdh_secret(tfm, pub_b, dhkey_a);
if (ret)
goto out;
@@ -165,9 +165,17 @@ static int __init test_ecdh_sample(struct crypto_kpp *tfm, const u8 priv_a[32],
goto out;
}
+ ret = set_ecdh_privkey(tfm, priv_b);
+ if (ret)
+ goto out;
+
+ ret = compute_ecdh_secret(tfm, pub_a, dhkey_b);
+ if (ret)
+ goto out;
+
if (memcmp(dhkey_b, dhkey, 32))
ret = -EINVAL;
-
+ /* fall through*/
out:
kfree(tmp);
return ret;
diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index af7e6100e55b..d41449b9e9d6 100644
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -84,7 +84,6 @@ enum {
struct smp_dev {
/* Secure Connections OOB data */
u8 local_pk[64];
- u8 local_sk[32];
u8 local_rand[16];
bool debug_key;
@@ -126,7 +125,6 @@ struct smp_chan {
/* Secure Connections variables */
u8 local_pk[64];
- u8 local_sk[32];
u8 remote_pk[64];
u8 dhkey[32];
u8 mackey[16];
@@ -568,24 +566,22 @@ int smp_generate_oob(struct hci_dev *hdev, u8 hash[16], u8 rand[16])
if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
BT_DBG("Using debug keys");
+ err = set_ecdh_privkey(smp->tfm_ecdh, debug_sk);
+ if (err)
+ return err;
memcpy(smp->local_pk, debug_pk, 64);
- memcpy(smp->local_sk, debug_sk, 32);
smp->debug_key = true;
} else {
while (true) {
- /* Seed private key with random number */
- get_random_bytes(smp->local_sk, 32);
-
- /* Generate local key pair for Secure Connections */
- err = generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk,
- smp->local_sk);
+ /* Generate key pair for Secure Connections */
+ err = generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk);
if (err)
return err;
/* This is unlikely, but we need to check that
* we didn't accidentially generate a debug key.
*/
- if (crypto_memneq(smp->local_sk, debug_sk, 32))
+ if (crypto_memneq(smp->local_pk, debug_pk, 64))
break;
}
smp->debug_key = false;
@@ -593,7 +589,6 @@ int smp_generate_oob(struct hci_dev *hdev, u8 hash[16], u8 rand[16])
SMP_DBG("OOB Public Key X: %32phN", smp->local_pk);
SMP_DBG("OOB Public Key Y: %32phN", smp->local_pk + 32);
- SMP_DBG("OOB Private Key: %32phN", smp->local_sk);
get_random_bytes(smp->local_rand, 16);
@@ -1900,7 +1895,6 @@ static u8 sc_send_public_key(struct smp_chan *smp)
smp_dev = chan->data;
memcpy(smp->local_pk, smp_dev->local_pk, 64);
- memcpy(smp->local_sk, smp_dev->local_sk, 32);
memcpy(smp->lr, smp_dev->local_rand, 16);
if (smp_dev->debug_key)
@@ -1911,23 +1905,20 @@ static u8 sc_send_public_key(struct smp_chan *smp)
if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) {
BT_DBG("Using debug keys");
+ if (set_ecdh_privkey(smp->tfm_ecdh, debug_sk))
+ return SMP_UNSPECIFIED;
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) {
- /* Seed private key with random number */
- get_random_bytes(smp->local_sk, 32);
-
- /* Generate local key pair for Secure Connections */
- if (generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk,
- smp->local_sk))
+ /* Generate key pair for Secure Connections */
+ if (generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk))
return SMP_UNSPECIFIED;
/* This is unlikely, but we need to check that
* we didn't accidentially generate a debug key.
*/
- if (crypto_memneq(smp->local_sk, debug_sk, 32))
+ if (crypto_memneq(smp->local_pk, debug_pk, 64))
break;
}
}
@@ -1935,7 +1926,6 @@ static u8 sc_send_public_key(struct smp_chan *smp)
done:
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);
@@ -2663,6 +2653,7 @@ static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb)
struct l2cap_chan *chan = conn->smp;
struct smp_chan *smp = chan->data;
struct hci_dev *hdev = hcon->hdev;
+ struct crypto_kpp *tfm_ecdh;
struct smp_cmd_pairing_confirm cfm;
int err;
@@ -2695,8 +2686,18 @@ static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb)
SMP_DBG("Remote Public Key X: %32phN", smp->remote_pk);
SMP_DBG("Remote Public Key Y: %32phN", smp->remote_pk + 32);
- if (!compute_ecdh_secret(smp->tfm_ecdh, smp->remote_pk, smp->local_sk,
- smp->dhkey))
+ /* Compute the shared secret on the same crypto tfm on which the private
+ * key was set/generated.
+ */
+ if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) {
+ struct smp_dev *smp_dev = chan->data;
+
+ tfm_ecdh = smp_dev->tfm_ecdh;
+ } else {
+ tfm_ecdh = smp->tfm_ecdh;
+ }
+
+ if (compute_ecdh_secret(tfm_ecdh, smp->remote_pk, smp->dhkey))
return SMP_UNSPECIFIED;
SMP_DBG("DHKey %32phN", smp->dhkey);
@@ -3522,27 +3523,18 @@ void smp_unregister(struct hci_dev *hdev)
#if IS_ENABLED(CONFIG_BT_SELFTEST_SMP)
-static inline void swap_digits(u64 *in, u64 *out, unsigned int ndigits)
-{
- int i;
-
- for (i = 0; i < ndigits; i++)
- out[i] = __swab64(in[ndigits - 1 - i]);
-}
-
static int __init test_debug_key(struct crypto_kpp *tfm_ecdh)
{
- u8 pk[64], sk[32];
+ u8 pk[64];
int err;
- swap_digits((u64 *)debug_sk, (u64 *)sk, 4);
-
- err = generate_ecdh_keys(tfm_ecdh, pk, sk);
+ err = set_ecdh_privkey(tfm_ecdh, debug_sk);
if (err)
return err;
- if (crypto_memneq(sk, debug_sk, 32))
- return -EINVAL;
+ err = generate_ecdh_public_key(tfm_ecdh, pk);
+ if (err)
+ return err;
if (crypto_memneq(pk, debug_pk, 64))
return -EINVAL;
generated by cgit (git 2.34.1) at 2024-06-13 14:27:02 +0000