diff options
Diffstat (limited to 'include/crypto/aead.h')
| -rw-r--r-- | include/crypto/aead.h | 234 |
1 files changed, 162 insertions, 72 deletions
diff --git a/include/crypto/aead.h b/include/crypto/aead.h index 9ad595f97c65..8e66a1fa9c78 100644 --- a/include/crypto/aead.h +++ b/include/crypto/aead.h @@ -1,21 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ /* * AEAD: Authenticated Encryption with Associated Data * * Copyright (c) 2007-2015 Herbert Xu <herbert@gondor.apana.org.au> - * - * This program is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License as published by the Free - * Software Foundation; either version 2 of the License, or (at your option) - * any later version. - * */ #ifndef _CRYPTO_AEAD_H #define _CRYPTO_AEAD_H +#include <linux/atomic.h> +#include <linux/container_of.h> #include <linux/crypto.h> -#include <linux/kernel.h> #include <linux/slab.h> +#include <linux/types.h> /** * DOC: Authenticated Encryption With Associated Data (AEAD) Cipher API @@ -31,15 +28,12 @@ * * For example: authenc(hmac(sha256), cbc(aes)) * - * The example code provided for the symmetric key cipher operation - * applies here as well. Naturally all *skcipher* symbols must be exchanged - * the *aead* pendants discussed in the following. In addition, for the AEAD - * operation, the aead_request_set_ad function must be used to set the - * pointer to the associated data memory location before performing the - * encryption or decryption operation. In case of an encryption, the associated - * data memory is filled during the encryption operation. For decryption, the - * associated data memory must contain data that is used to verify the integrity - * of the decrypted data. Another deviation from the asynchronous block cipher + * The example code provided for the symmetric key cipher operation applies + * here as well. Naturally all *skcipher* symbols must be exchanged the *aead* + * pendants discussed in the following. In addition, for the AEAD operation, + * the aead_request_set_ad function must be used to set the pointer to the + * associated data memory location before performing the encryption or + * decryption operation. Another deviation from the asynchronous block cipher * operation is that the caller should explicitly check for -EBADMSG of the * crypto_aead_decrypt. That error indicates an authentication error, i.e. * a breach in the integrity of the message. In essence, that -EBADMSG error @@ -48,30 +42,40 @@ * * Memory Structure: * - * To support the needs of the most prominent user of AEAD ciphers, namely - * IPSEC, the AEAD ciphers have a special memory layout the caller must adhere - * to. - * - * The scatter list pointing to the input data must contain: - * - * * for RFC4106 ciphers, the concatenation of - * associated authentication data || IV || plaintext or ciphertext. Note, the - * same IV (buffer) is also set with the aead_request_set_crypt call. Note, - * the API call of aead_request_set_ad must provide the length of the AAD and - * the IV. The API call of aead_request_set_crypt only points to the size of - * the input plaintext or ciphertext. - * - * * for "normal" AEAD ciphers, the concatenation of - * associated authentication data || plaintext or ciphertext. - * - * It is important to note that if multiple scatter gather list entries form - * the input data mentioned above, the first entry must not point to a NULL - * buffer. If there is any potential where the AAD buffer can be NULL, the - * calling code must contain a precaution to ensure that this does not result - * in the first scatter gather list entry pointing to a NULL buffer. + * The source scatterlist must contain the concatenation of + * associated data || plaintext or ciphertext. + * + * The destination scatterlist has the same layout, except that the plaintext + * (resp. ciphertext) will grow (resp. shrink) by the authentication tag size + * during encryption (resp. decryption). The authentication tag is generated + * during the encryption operation and appended to the ciphertext. During + * decryption, the authentication tag is consumed along with the ciphertext and + * used to verify the integrity of the plaintext and the associated data. + * + * In-place encryption/decryption is enabled by using the same scatterlist + * pointer for both the source and destination. + * + * Even in the out-of-place case, space must be reserved in the destination for + * the associated data, even though it won't be written to. This makes the + * in-place and out-of-place cases more consistent. It is permissible for the + * "destination" associated data to alias the "source" associated data. + * + * As with the other scatterlist crypto APIs, zero-length scatterlist elements + * are not allowed in the used part of the scatterlist. Thus, if there is no + * associated data, the first element must point to the plaintext/ciphertext. + * + * To meet the needs of IPsec, a special quirk applies to rfc4106, rfc4309, + * rfc4543, and rfc7539esp ciphers. For these ciphers, the final 'ivsize' bytes + * of the associated data buffer must contain a second copy of the IV. This is + * in addition to the copy passed to aead_request_set_crypt(). These two IV + * copies must not differ; different implementations of the same algorithm may + * behave differently in that case. Note that the algorithm might not actually + * treat the IV as associated data; nevertheless the length passed to + * aead_request_set_ad() must include it. */ struct crypto_aead; +struct scatterlist; /** * struct aead_request - AEAD request @@ -155,6 +159,21 @@ struct crypto_aead { struct crypto_tfm base; }; +struct crypto_sync_aead { + struct crypto_aead base; +}; + +#define MAX_SYNC_AEAD_REQSIZE 384 + +#define SYNC_AEAD_REQUEST_ON_STACK(name, _tfm) \ + char __##name##_desc[sizeof(struct aead_request) + \ + MAX_SYNC_AEAD_REQSIZE \ + ] CRYPTO_MINALIGN_ATTR; \ + struct aead_request *name = \ + (((struct aead_request *)__##name##_desc)->base.tfm = \ + crypto_sync_aead_tfm((_tfm)), \ + (void *)__##name##_desc) + static inline struct crypto_aead *__crypto_aead_cast(struct crypto_tfm *tfm) { return container_of(tfm, struct crypto_aead, base); @@ -176,20 +195,51 @@ static inline struct crypto_aead *__crypto_aead_cast(struct crypto_tfm *tfm) */ struct crypto_aead *crypto_alloc_aead(const char *alg_name, u32 type, u32 mask); +struct crypto_sync_aead *crypto_alloc_sync_aead(const char *alg_name, u32 type, u32 mask); + static inline struct crypto_tfm *crypto_aead_tfm(struct crypto_aead *tfm) { return &tfm->base; } +static inline struct crypto_tfm *crypto_sync_aead_tfm(struct crypto_sync_aead *tfm) +{ + return crypto_aead_tfm(&tfm->base); +} + /** * crypto_free_aead() - zeroize and free aead handle * @tfm: cipher handle to be freed + * + * If @tfm is a NULL or error pointer, this function does nothing. */ static inline void crypto_free_aead(struct crypto_aead *tfm) { crypto_destroy_tfm(tfm, crypto_aead_tfm(tfm)); } +static inline void crypto_free_sync_aead(struct crypto_sync_aead *tfm) +{ + crypto_free_aead(&tfm->base); +} + +/** + * crypto_has_aead() - Search for the availability of an aead. + * @alg_name: is the cra_name / name or cra_driver_name / driver name of the + * aead + * @type: specifies the type of the aead + * @mask: specifies the mask for the aead + * + * Return: true when the aead is known to the kernel crypto API; false + * otherwise + */ +int crypto_has_aead(const char *alg_name, u32 type, u32 mask); + +static inline const char *crypto_aead_driver_name(struct crypto_aead *tfm) +{ + return crypto_tfm_alg_driver_name(crypto_aead_tfm(tfm)); +} + static inline struct aead_alg *crypto_aead_alg(struct crypto_aead *tfm) { return container_of(crypto_aead_tfm(tfm)->__crt_alg, @@ -215,6 +265,11 @@ static inline unsigned int crypto_aead_ivsize(struct crypto_aead *tfm) return crypto_aead_alg_ivsize(crypto_aead_alg(tfm)); } +static inline unsigned int crypto_sync_aead_ivsize(struct crypto_sync_aead *tfm) +{ + return crypto_aead_ivsize(&tfm->base); +} + /** * crypto_aead_authsize() - obtain maximum authentication data size * @tfm: cipher handle @@ -232,6 +287,26 @@ static inline unsigned int crypto_aead_authsize(struct crypto_aead *tfm) return tfm->authsize; } +static inline unsigned int crypto_sync_aead_authsize(struct crypto_sync_aead *tfm) +{ + return crypto_aead_authsize(&tfm->base); +} + +static inline unsigned int crypto_aead_alg_maxauthsize(struct aead_alg *alg) +{ + return alg->maxauthsize; +} + +static inline unsigned int crypto_aead_maxauthsize(struct crypto_aead *aead) +{ + return crypto_aead_alg_maxauthsize(crypto_aead_alg(aead)); +} + +static inline unsigned int crypto_sync_aead_maxauthsize(struct crypto_sync_aead *tfm) +{ + return crypto_aead_maxauthsize(&tfm->base); +} + /** * crypto_aead_blocksize() - obtain block size of cipher * @tfm: cipher handle @@ -247,6 +322,11 @@ static inline unsigned int crypto_aead_blocksize(struct crypto_aead *tfm) return crypto_tfm_alg_blocksize(crypto_aead_tfm(tfm)); } +static inline unsigned int crypto_sync_aead_blocksize(struct crypto_sync_aead *tfm) +{ + return crypto_aead_blocksize(&tfm->base); +} + static inline unsigned int crypto_aead_alignmask(struct crypto_aead *tfm) { return crypto_tfm_alg_alignmask(crypto_aead_tfm(tfm)); @@ -267,6 +347,21 @@ static inline void crypto_aead_clear_flags(struct crypto_aead *tfm, u32 flags) crypto_tfm_clear_flags(crypto_aead_tfm(tfm), flags); } +static inline u32 crypto_sync_aead_get_flags(struct crypto_sync_aead *tfm) +{ + return crypto_aead_get_flags(&tfm->base); +} + +static inline void crypto_sync_aead_set_flags(struct crypto_sync_aead *tfm, u32 flags) +{ + crypto_aead_set_flags(&tfm->base, flags); +} + +static inline void crypto_sync_aead_clear_flags(struct crypto_sync_aead *tfm, u32 flags) +{ + crypto_aead_clear_flags(&tfm->base, flags); +} + /** * crypto_aead_setkey() - set key for cipher * @tfm: cipher handle @@ -286,6 +381,12 @@ static inline void crypto_aead_clear_flags(struct crypto_aead *tfm, u32 flags) int crypto_aead_setkey(struct crypto_aead *tfm, const u8 *key, unsigned int keylen); +static inline int crypto_sync_aead_setkey(struct crypto_sync_aead *tfm, + const u8 *key, unsigned int keylen) +{ + return crypto_aead_setkey(&tfm->base, key, keylen); +} + /** * crypto_aead_setauthsize() - set authentication data size * @tfm: cipher handle @@ -298,11 +399,24 @@ int crypto_aead_setkey(struct crypto_aead *tfm, */ int crypto_aead_setauthsize(struct crypto_aead *tfm, unsigned int authsize); +static inline int crypto_sync_aead_setauthsize(struct crypto_sync_aead *tfm, + unsigned int authsize) +{ + return crypto_aead_setauthsize(&tfm->base, authsize); +} + static inline struct crypto_aead *crypto_aead_reqtfm(struct aead_request *req) { return __crypto_aead_cast(req->base.tfm); } +static inline struct crypto_sync_aead *crypto_sync_aead_reqtfm(struct aead_request *req) +{ + struct crypto_aead *tfm = crypto_aead_reqtfm(req); + + return container_of(tfm, struct crypto_sync_aead, base); +} + /** * crypto_aead_encrypt() - encrypt plaintext * @req: reference to the aead_request handle that holds all information @@ -322,25 +436,11 @@ static inline struct crypto_aead *crypto_aead_reqtfm(struct aead_request *req) * * Return: 0 if the cipher operation was successful; < 0 if an error occurred */ -static inline int crypto_aead_encrypt(struct aead_request *req) -{ - struct crypto_aead *aead = crypto_aead_reqtfm(req); - struct crypto_alg *alg = aead->base.__crt_alg; - unsigned int cryptlen = req->cryptlen; - int ret; - - crypto_stats_get(alg); - if (crypto_aead_get_flags(aead) & CRYPTO_TFM_NEED_KEY) - ret = -ENOKEY; - else - ret = crypto_aead_alg(aead)->encrypt(req); - crypto_stats_aead_encrypt(cryptlen, alg, ret); - return ret; -} +int crypto_aead_encrypt(struct aead_request *req); /** * crypto_aead_decrypt() - decrypt ciphertext - * @req: reference to the ablkcipher_request handle that holds all information + * @req: reference to the aead_request handle that holds all information * needed to perform the cipher operation * * Decrypt ciphertext data using the aead_request handle. That data structure @@ -360,23 +460,7 @@ static inline int crypto_aead_encrypt(struct aead_request *req) * integrity of the ciphertext or the associated data was violated); * < 0 if an error occurred. */ -static inline int crypto_aead_decrypt(struct aead_request *req) -{ - struct crypto_aead *aead = crypto_aead_reqtfm(req); - struct crypto_alg *alg = aead->base.__crt_alg; - unsigned int cryptlen = req->cryptlen; - int ret; - - crypto_stats_get(alg); - if (crypto_aead_get_flags(aead) & CRYPTO_TFM_NEED_KEY) - ret = -ENOKEY; - else if (req->cryptlen < crypto_aead_authsize(aead)) - ret = -EINVAL; - else - ret = crypto_aead_alg(aead)->decrypt(req); - crypto_stats_aead_decrypt(cryptlen, alg, ret); - return ret; -} +int crypto_aead_decrypt(struct aead_request *req); /** * DOC: Asynchronous AEAD Request Handle @@ -414,6 +498,12 @@ static inline void aead_request_set_tfm(struct aead_request *req, req->base.tfm = crypto_aead_tfm(tfm); } +static inline void aead_request_set_sync_tfm(struct aead_request *req, + struct crypto_sync_aead *tfm) +{ + aead_request_set_tfm(req, &tfm->base); +} + /** * aead_request_alloc() - allocate request data structure * @tfm: cipher handle to be registered with the request @@ -444,7 +534,7 @@ static inline struct aead_request *aead_request_alloc(struct crypto_aead *tfm, */ static inline void aead_request_free(struct aead_request *req) { - kzfree(req); + kfree_sensitive(req); } /** @@ -502,7 +592,7 @@ static inline void aead_request_set_callback(struct aead_request *req, * The memory structure for cipher operation has the following structure: * * - AEAD encryption input: assoc data || plaintext - * - AEAD encryption output: assoc data || cipherntext || auth tag + * - AEAD encryption output: assoc data || ciphertext || auth tag * - AEAD decryption input: assoc data || ciphertext || auth tag * - AEAD decryption output: assoc data || plaintext * |