1/* 2 * Copyright 2003-2004, Instant802 Networks, Inc. 3 * Copyright 2005-2006, Devicescape Software, Inc. 4 * 5 * Rewrite: Copyright (C) 2013 Linaro Ltd <ard.biesheuvel@linaro.org> 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 */ 11 12#include <linux/kernel.h> 13#include <linux/types.h> 14#include <linux/crypto.h> 15#include <linux/err.h> 16#include <crypto/aes.h> 17 18#include <net/mac80211.h> 19#include "key.h" 20#include "aes_ccm.h" 21 22void ieee80211_aes_ccm_encrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad, 23 u8 *data, size_t data_len, u8 *mic) 24{ 25 struct scatterlist assoc, pt, ct[2]; 26 27 char aead_req_data[sizeof(struct aead_request) + 28 crypto_aead_reqsize(tfm)] 29 __aligned(__alignof__(struct aead_request)); 30 struct aead_request *aead_req = (void *) aead_req_data; 31 32 memset(aead_req, 0, sizeof(aead_req_data)); 33 34 sg_init_one(&pt, data, data_len); 35 sg_init_one(&assoc, &aad[2], be16_to_cpup((__be16 *)aad)); 36 sg_init_table(ct, 2); 37 sg_set_buf(&ct[0], data, data_len); 38 sg_set_buf(&ct[1], mic, IEEE80211_CCMP_MIC_LEN); 39 40 aead_request_set_tfm(aead_req, tfm); 41 aead_request_set_assoc(aead_req, &assoc, assoc.length); 42 aead_request_set_crypt(aead_req, &pt, ct, data_len, b_0); 43 44 crypto_aead_encrypt(aead_req); 45} 46 47int ieee80211_aes_ccm_decrypt(struct crypto_aead *tfm, u8 *b_0, u8 *aad, 48 u8 *data, size_t data_len, u8 *mic) 49{ 50 struct scatterlist assoc, pt, ct[2]; 51 char aead_req_data[sizeof(struct aead_request) + 52 crypto_aead_reqsize(tfm)] 53 __aligned(__alignof__(struct aead_request)); 54 struct aead_request *aead_req = (void *) aead_req_data; 55 56 if (data_len == 0) 57 return -EINVAL; 58 59 memset(aead_req, 0, sizeof(aead_req_data)); 60 61 sg_init_one(&pt, data, data_len); 62 sg_init_one(&assoc, &aad[2], be16_to_cpup((__be16 *)aad)); 63 sg_init_table(ct, 2); 64 sg_set_buf(&ct[0], data, data_len); 65 sg_set_buf(&ct[1], mic, IEEE80211_CCMP_MIC_LEN); 66 67 aead_request_set_tfm(aead_req, tfm); 68 aead_request_set_assoc(aead_req, &assoc, assoc.length); 69 aead_request_set_crypt(aead_req, ct, &pt, 70 data_len + IEEE80211_CCMP_MIC_LEN, b_0); 71 72 return crypto_aead_decrypt(aead_req); 73} 74 75struct crypto_aead *ieee80211_aes_key_setup_encrypt(const u8 key[]) 76{ 77 struct crypto_aead *tfm; 78 int err; 79 80 tfm = crypto_alloc_aead("ccm(aes)", 0, CRYPTO_ALG_ASYNC); 81 if (IS_ERR(tfm)) 82 return tfm; 83 84 err = crypto_aead_setkey(tfm, key, WLAN_KEY_LEN_CCMP); 85 if (!err) 86 err = crypto_aead_setauthsize(tfm, IEEE80211_CCMP_MIC_LEN); 87 if (!err) 88 return tfm; 89 90 crypto_free_aead(tfm); 91 return ERR_PTR(err); 92} 93 94void ieee80211_aes_key_free(struct crypto_aead *tfm) 95{ 96 crypto_free_aead(tfm); 97} 98