83 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			83 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * AES-GMAC for IEEE 802.11 BIP-GMAC-128 and BIP-GMAC-256
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|  * Copyright 2015, Qualcomm Atheros, Inc.
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|  *
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|  * This program is free software; you can redistribute it and/or modify
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|  * it under the terms of the GNU General Public License version 2 as
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|  * published by the Free Software Foundation.
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|  */
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| 
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| #include <linux/kernel.h>
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| #include <linux/types.h>
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| #include <linux/err.h>
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| #include <crypto/aead.h>
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| #include <crypto/aes.h>
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| 
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| #include <net/mac80211.h>
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| #include "key.h"
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| #include "aes_gmac.h"
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| 
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| int ieee80211_aes_gmac(struct crypto_aead *tfm, const u8 *aad, u8 *nonce,
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| 		       const u8 *data, size_t data_len, u8 *mic)
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| {
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| 	struct scatterlist sg[4];
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| 	u8 *zero, *__aad, iv[AES_BLOCK_SIZE];
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| 	struct aead_request *aead_req;
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| 	int reqsize = sizeof(*aead_req) + crypto_aead_reqsize(tfm);
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| 
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| 	if (data_len < GMAC_MIC_LEN)
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| 		return -EINVAL;
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| 
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| 	aead_req = kzalloc(reqsize + GMAC_MIC_LEN + GMAC_AAD_LEN, GFP_ATOMIC);
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| 	if (!aead_req)
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| 		return -ENOMEM;
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| 
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| 	zero = (u8 *)aead_req + reqsize;
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| 	__aad = zero + GMAC_MIC_LEN;
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| 	memcpy(__aad, aad, GMAC_AAD_LEN);
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| 
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| 	sg_init_table(sg, 4);
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| 	sg_set_buf(&sg[0], __aad, GMAC_AAD_LEN);
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| 	sg_set_buf(&sg[1], data, data_len - GMAC_MIC_LEN);
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| 	sg_set_buf(&sg[2], zero, GMAC_MIC_LEN);
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| 	sg_set_buf(&sg[3], mic, GMAC_MIC_LEN);
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| 
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| 	memcpy(iv, nonce, GMAC_NONCE_LEN);
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| 	memset(iv + GMAC_NONCE_LEN, 0, sizeof(iv) - GMAC_NONCE_LEN);
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| 	iv[AES_BLOCK_SIZE - 1] = 0x01;
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| 
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| 	aead_request_set_tfm(aead_req, tfm);
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| 	aead_request_set_crypt(aead_req, sg, sg, 0, iv);
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| 	aead_request_set_ad(aead_req, GMAC_AAD_LEN + data_len);
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| 
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| 	crypto_aead_encrypt(aead_req);
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| 	kzfree(aead_req);
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| 
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| 	return 0;
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| }
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| 
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| struct crypto_aead *ieee80211_aes_gmac_key_setup(const u8 key[],
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| 						 size_t key_len)
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| {
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| 	struct crypto_aead *tfm;
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| 	int err;
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| 
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| 	tfm = crypto_alloc_aead("gcm(aes)", 0, CRYPTO_ALG_ASYNC);
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| 	if (IS_ERR(tfm))
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| 		return tfm;
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| 
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| 	err = crypto_aead_setkey(tfm, key, key_len);
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| 	if (!err)
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| 		err = crypto_aead_setauthsize(tfm, GMAC_MIC_LEN);
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| 	if (!err)
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| 		return tfm;
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| 
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| 	crypto_free_aead(tfm);
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| 	return ERR_PTR(err);
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| }
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| 
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| void ieee80211_aes_gmac_key_free(struct crypto_aead *tfm)
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| {
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| 	crypto_free_aead(tfm);
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| }
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