Return-Path: MIME-Version: 1.0 In-Reply-To: <264af59a3060c2bc2a725cfc66a8fa68219d1c4a.1468270393.git.luto@kernel.org> References: <264af59a3060c2bc2a725cfc66a8fa68219d1c4a.1468270393.git.luto@kernel.org> From: Andy Lutomirski Date: Thu, 14 Jul 2016 12:10:45 -0700 Message-ID: Subject: Re: [PATCH v5 01/32] bluetooth: Switch SMP to crypto_cipher_encrypt_one() To: Andy Lutomirski , "David S. Miller" Cc: X86 ML , "linux-kernel@vger.kernel.org" , linux-arch , Borislav Petkov , Nadav Amit , Kees Cook , Brian Gerst , "kernel-hardening@lists.openwall.com" , Linus Torvalds , Josh Poimboeuf , Jann Horn , Heiko Carstens , Marcel Holtmann , Gustavo Padovan , Johan Hedberg , linux-bluetooth@vger.kernel.org, Network Development Content-Type: text/plain; charset=UTF-8 List-ID: On Mon, Jul 11, 2016 at 1:53 PM, Andy Lutomirski wrote: > SMP does ECB crypto on stack buffers. This is complicated and > fragile, and it will not work if the stack is virtually allocated. > > Switch to the crypto_cipher interface, which is simpler and safer. Hi Dave- It looks like we're delaying virtually mapped stacks to 4.9. That means that there's time for this to go in through net-next. Could you queue it up? --Andy > > Cc: Marcel Holtmann > Cc: Gustavo Padovan > Cc: Johan Hedberg > Cc: "David S. Miller" > Cc: linux-bluetooth@vger.kernel.org > Cc: netdev@vger.kernel.org > Acked-by: Herbert Xu > Acked-and-tested-by: Johan Hedberg > Signed-off-by: Andy Lutomirski > --- > net/bluetooth/smp.c | 67 ++++++++++++++++++++++------------------------------- > 1 file changed, 28 insertions(+), 39 deletions(-) > > diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c > index 50976a6481f3..4c1a16a96ae5 100644 > --- a/net/bluetooth/smp.c > +++ b/net/bluetooth/smp.c > @@ -22,9 +22,9 @@ > > #include > #include > +#include > #include > #include > -#include > > #include > #include > @@ -88,7 +88,7 @@ struct smp_dev { > u8 min_key_size; > u8 max_key_size; > > - struct crypto_skcipher *tfm_aes; > + struct crypto_cipher *tfm_aes; > struct crypto_shash *tfm_cmac; > }; > > @@ -127,7 +127,7 @@ struct smp_chan { > u8 dhkey[32]; > u8 mackey[16]; > > - struct crypto_skcipher *tfm_aes; > + struct crypto_cipher *tfm_aes; > struct crypto_shash *tfm_cmac; > }; > > @@ -361,10 +361,8 @@ static int smp_h6(struct crypto_shash *tfm_cmac, const u8 w[16], > * s1 and ah. > */ > > -static int smp_e(struct crypto_skcipher *tfm, const u8 *k, u8 *r) > +static int smp_e(struct crypto_cipher *tfm, const u8 *k, u8 *r) > { > - SKCIPHER_REQUEST_ON_STACK(req, tfm); > - struct scatterlist sg; > uint8_t tmp[16], data[16]; > int err; > > @@ -378,7 +376,7 @@ static int smp_e(struct crypto_skcipher *tfm, const u8 *k, u8 *r) > /* The most significant octet of key corresponds to k[0] */ > swap_buf(k, tmp, 16); > > - err = crypto_skcipher_setkey(tfm, tmp, 16); > + err = crypto_cipher_setkey(tfm, tmp, 16); > if (err) { > BT_ERR("cipher setkey failed: %d", err); > return err; > @@ -387,16 +385,7 @@ static int smp_e(struct crypto_skcipher *tfm, const u8 *k, u8 *r) > /* Most significant octet of plaintextData corresponds to data[0] */ > swap_buf(r, data, 16); > > - sg_init_one(&sg, data, 16); > - > - skcipher_request_set_tfm(req, tfm); > - skcipher_request_set_callback(req, 0, NULL, NULL); > - skcipher_request_set_crypt(req, &sg, &sg, 16, NULL); > - > - err = crypto_skcipher_encrypt(req); > - skcipher_request_zero(req); > - if (err) > - BT_ERR("Encrypt data error %d", err); > + crypto_cipher_encrypt_one(tfm, data, data); > > /* Most significant octet of encryptedData corresponds to data[0] */ > swap_buf(data, r, 16); > @@ -406,7 +395,7 @@ static int smp_e(struct crypto_skcipher *tfm, const u8 *k, u8 *r) > return err; > } > > -static int smp_c1(struct crypto_skcipher *tfm_aes, const u8 k[16], > +static int smp_c1(struct crypto_cipher *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]) > { > @@ -455,7 +444,7 @@ static int smp_c1(struct crypto_skcipher *tfm_aes, const u8 k[16], > return err; > } > > -static int smp_s1(struct crypto_skcipher *tfm_aes, const u8 k[16], > +static int smp_s1(struct crypto_cipher *tfm_aes, const u8 k[16], > const u8 r1[16], const u8 r2[16], u8 _r[16]) > { > int err; > @@ -471,7 +460,7 @@ static int smp_s1(struct crypto_skcipher *tfm_aes, const u8 k[16], > return err; > } > > -static int smp_ah(struct crypto_skcipher *tfm, const u8 irk[16], > +static int smp_ah(struct crypto_cipher *tfm, const u8 irk[16], > const u8 r[3], u8 res[3]) > { > u8 _res[16]; > @@ -759,7 +748,7 @@ static void smp_chan_destroy(struct l2cap_conn *conn) > kzfree(smp->slave_csrk); > kzfree(smp->link_key); > > - crypto_free_skcipher(smp->tfm_aes); > + crypto_free_cipher(smp->tfm_aes); > crypto_free_shash(smp->tfm_cmac); > > /* Ensure that we don't leave any debug key around if debug key > @@ -1359,9 +1348,9 @@ static struct smp_chan *smp_chan_create(struct l2cap_conn *conn) > if (!smp) > return NULL; > > - smp->tfm_aes = crypto_alloc_skcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC); > + smp->tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC); > if (IS_ERR(smp->tfm_aes)) { > - BT_ERR("Unable to create ECB crypto context"); > + BT_ERR("Unable to create AES crypto context"); > kzfree(smp); > return NULL; > } > @@ -1369,7 +1358,7 @@ static struct smp_chan *smp_chan_create(struct l2cap_conn *conn) > smp->tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0); > if (IS_ERR(smp->tfm_cmac)) { > BT_ERR("Unable to create CMAC crypto context"); > - crypto_free_skcipher(smp->tfm_aes); > + crypto_free_cipher(smp->tfm_aes); > kzfree(smp); > return NULL; > } > @@ -3120,7 +3109,7 @@ static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid) > { > struct l2cap_chan *chan; > struct smp_dev *smp; > - struct crypto_skcipher *tfm_aes; > + struct crypto_cipher *tfm_aes; > struct crypto_shash *tfm_cmac; > > if (cid == L2CAP_CID_SMP_BREDR) { > @@ -3132,9 +3121,9 @@ static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid) > if (!smp) > return ERR_PTR(-ENOMEM); > > - tfm_aes = crypto_alloc_skcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC); > + tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC); > if (IS_ERR(tfm_aes)) { > - BT_ERR("Unable to create ECB crypto context"); > + BT_ERR("Unable to create AES crypto context"); > kzfree(smp); > return ERR_CAST(tfm_aes); > } > @@ -3142,7 +3131,7 @@ static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid) > tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0); > if (IS_ERR(tfm_cmac)) { > BT_ERR("Unable to create CMAC crypto context"); > - crypto_free_skcipher(tfm_aes); > + crypto_free_cipher(tfm_aes); > kzfree(smp); > return ERR_CAST(tfm_cmac); > } > @@ -3156,7 +3145,7 @@ create_chan: > chan = l2cap_chan_create(); > if (!chan) { > if (smp) { > - crypto_free_skcipher(smp->tfm_aes); > + crypto_free_cipher(smp->tfm_aes); > crypto_free_shash(smp->tfm_cmac); > kzfree(smp); > } > @@ -3203,7 +3192,7 @@ static void smp_del_chan(struct l2cap_chan *chan) > smp = chan->data; > if (smp) { > chan->data = NULL; > - crypto_free_skcipher(smp->tfm_aes); > + crypto_free_cipher(smp->tfm_aes); > crypto_free_shash(smp->tfm_cmac); > kzfree(smp); > } > @@ -3440,7 +3429,7 @@ void smp_unregister(struct hci_dev *hdev) > > #if IS_ENABLED(CONFIG_BT_SELFTEST_SMP) > > -static int __init test_ah(struct crypto_skcipher *tfm_aes) > +static int __init test_ah(struct crypto_cipher *tfm_aes) > { > const u8 irk[16] = { > 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, > @@ -3460,7 +3449,7 @@ static int __init test_ah(struct crypto_skcipher *tfm_aes) > return 0; > } > > -static int __init test_c1(struct crypto_skcipher *tfm_aes) > +static int __init test_c1(struct crypto_cipher *tfm_aes) > { > const u8 k[16] = { > 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, > @@ -3490,7 +3479,7 @@ static int __init test_c1(struct crypto_skcipher *tfm_aes) > return 0; > } > > -static int __init test_s1(struct crypto_skcipher *tfm_aes) > +static int __init test_s1(struct crypto_cipher *tfm_aes) > { > const u8 k[16] = { > 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, > @@ -3686,7 +3675,7 @@ static const struct file_operations test_smp_fops = { > .llseek = default_llseek, > }; > > -static int __init run_selftests(struct crypto_skcipher *tfm_aes, > +static int __init run_selftests(struct crypto_cipher *tfm_aes, > struct crypto_shash *tfm_cmac) > { > ktime_t calltime, delta, rettime; > @@ -3764,27 +3753,27 @@ done: > > int __init bt_selftest_smp(void) > { > - struct crypto_skcipher *tfm_aes; > + struct crypto_cipher *tfm_aes; > struct crypto_shash *tfm_cmac; > int err; > > - tfm_aes = crypto_alloc_skcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC); > + tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC); > if (IS_ERR(tfm_aes)) { > - BT_ERR("Unable to create ECB crypto context"); > + BT_ERR("Unable to create AES crypto context"); > return PTR_ERR(tfm_aes); > } > > tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, CRYPTO_ALG_ASYNC); > if (IS_ERR(tfm_cmac)) { > BT_ERR("Unable to create CMAC crypto context"); > - crypto_free_skcipher(tfm_aes); > + crypto_free_cipher(tfm_aes); > return PTR_ERR(tfm_cmac); > } > > err = run_selftests(tfm_aes, tfm_cmac); > > crypto_free_shash(tfm_cmac); > - crypto_free_skcipher(tfm_aes); > + crypto_free_cipher(tfm_aes); > > return err; > } > -- > 2.7.4 > -- Andy Lutomirski AMA Capital Management, LLC