[RFCv0 16/19] Bluetooth: Add function to derive AMP key using hmac
From: Andrei Emeltchenko <hidden>
Date: 2012-06-29 14:46:49
Subsystem:
bluetooth subsystem, the rest · Maintainers:
Marcel Holtmann, Luiz Augusto von Dentz, Linus Torvalds
From: Dmitry Kasatkin <redacted> hmac(sha256) will be used for AMP key generation. Signed-off-by: Andrei Emeltchenko <redacted> --- net/bluetooth/pal.c | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+)
diff --git a/net/bluetooth/pal.c b/net/bluetooth/pal.c
index 35c9934..1c74912 100644
--- a/net/bluetooth/pal.c
+++ b/net/bluetooth/pal.c@@ -226,3 +226,37 @@ struct phy_link *hci_phylink_lookup(struct amp_mgr *mgr, u8 local_id, return found; } + +int hmac_sha256(u8 *key, u8 ksize, char *plaintext, u8 psize, u8 *output) +{ + int ret = 0; + struct crypto_shash *tfm; + + tfm = crypto_alloc_shash("hmac(sha256)", 0, 0); + if (IS_ERR(tfm)) { + BT_DBG("crypto_alloc_ahash failed"); + return PTR_ERR(tfm); + } + + if (ksize) { + ret = crypto_shash_setkey(tfm, key, ksize); + if (ret) { + BT_DBG("crypto_ahash_setkey failed"); + } else { + struct { + struct shash_desc shash; + char ctx[crypto_shash_descsize(tfm)]; + } desc; + + desc.shash.tfm = tfm; + desc.shash.flags = CRYPTO_TFM_REQ_MAY_SLEEP; + + ret = crypto_shash_digest(&desc.shash, plaintext, psize, + output); + } + } + + BT_DBG("ret 0x%x", ret); + crypto_free_shash(tfm); + return ret; +}
--
1.7.9.5