diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
commit | 57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch) | |
tree | 5e910f0e82173f4ef4f51111366a3f1299037a7b /net/mac80211/aes_gmac.c |
Initial import
Diffstat (limited to 'net/mac80211/aes_gmac.c')
-rw-r--r-- | net/mac80211/aes_gmac.c | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/net/mac80211/aes_gmac.c b/net/mac80211/aes_gmac.c new file mode 100644 index 000000000..f1321b7d6 --- /dev/null +++ b/net/mac80211/aes_gmac.c @@ -0,0 +1,84 @@ +/* + * AES-GMAC for IEEE 802.11 BIP-GMAC-128 and BIP-GMAC-256 + * Copyright 2015, Qualcomm Atheros, Inc. + * + * 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. + */ + +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/crypto.h> +#include <linux/err.h> +#include <crypto/aes.h> + +#include <net/mac80211.h> +#include "key.h" +#include "aes_gmac.h" + +#define GMAC_MIC_LEN 16 +#define GMAC_NONCE_LEN 12 +#define AAD_LEN 20 + +int ieee80211_aes_gmac(struct crypto_aead *tfm, const u8 *aad, u8 *nonce, + const u8 *data, size_t data_len, u8 *mic) +{ + struct scatterlist sg[3], ct[1]; + char aead_req_data[sizeof(struct aead_request) + + crypto_aead_reqsize(tfm)] + __aligned(__alignof__(struct aead_request)); + struct aead_request *aead_req = (void *)aead_req_data; + u8 zero[GMAC_MIC_LEN], iv[AES_BLOCK_SIZE]; + + if (data_len < GMAC_MIC_LEN) + return -EINVAL; + + memset(aead_req, 0, sizeof(aead_req_data)); + + memset(zero, 0, GMAC_MIC_LEN); + sg_init_table(sg, 3); + sg_set_buf(&sg[0], aad, AAD_LEN); + sg_set_buf(&sg[1], data, data_len - GMAC_MIC_LEN); + sg_set_buf(&sg[2], zero, GMAC_MIC_LEN); + + memcpy(iv, nonce, GMAC_NONCE_LEN); + memset(iv + GMAC_NONCE_LEN, 0, sizeof(iv) - GMAC_NONCE_LEN); + iv[AES_BLOCK_SIZE - 1] = 0x01; + + sg_init_table(ct, 1); + sg_set_buf(&ct[0], mic, GMAC_MIC_LEN); + + aead_request_set_tfm(aead_req, tfm); + aead_request_set_assoc(aead_req, sg, AAD_LEN + data_len); + aead_request_set_crypt(aead_req, NULL, ct, 0, iv); + + crypto_aead_encrypt(aead_req); + + return 0; +} + +struct crypto_aead *ieee80211_aes_gmac_key_setup(const u8 key[], + size_t key_len) +{ + struct crypto_aead *tfm; + int err; + + tfm = crypto_alloc_aead("gcm(aes)", 0, CRYPTO_ALG_ASYNC); + if (IS_ERR(tfm)) + return tfm; + + err = crypto_aead_setkey(tfm, key, key_len); + if (!err) + err = crypto_aead_setauthsize(tfm, GMAC_MIC_LEN); + if (!err) + return tfm; + + crypto_free_aead(tfm); + return ERR_PTR(err); +} + +void ieee80211_aes_gmac_key_free(struct crypto_aead *tfm) +{ + crypto_free_aead(tfm); +} |