diff options
Diffstat (limited to 'include/crypto')
| -rw-r--r-- | include/crypto/aead.h | 50 | ||||
| -rw-r--r-- | include/crypto/dh.h | 58 | ||||
| -rw-r--r-- | include/crypto/ecdh.h | 58 | ||||
| -rw-r--r-- | include/crypto/hash.h | 2 | ||||
| -rw-r--r-- | include/crypto/kpp.h | 15 | ||||
| -rw-r--r-- | include/crypto/skcipher.h | 4 |
6 files changed, 150 insertions, 37 deletions
diff --git a/include/crypto/aead.h b/include/crypto/aead.h index 12f84327ca36..03b97629442c 100644 --- a/include/crypto/aead.h +++ b/include/crypto/aead.h @@ -55,14 +55,14 @@ * 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. + * 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. + * 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 @@ -452,7 +452,7 @@ static inline void aead_request_free(struct aead_request *req) * completes * * The callback function is registered with the aead_request handle and - * must comply with the following template + * must comply with the following template:: * * void callback_function(struct crypto_async_request *req, int error) */ @@ -483,30 +483,18 @@ static inline void aead_request_set_callback(struct aead_request *req, * destination is the ciphertext. For a decryption operation, the use is * reversed - the source is the ciphertext and the destination is the plaintext. * - * For both src/dst the layout is associated data, plain/cipher text, - * authentication tag. - * - * The content of the AD in the destination buffer after processing - * will either be untouched, or it will contain a copy of the AD - * from the source buffer. In order to ensure that it always has - * a copy of the AD, the user must copy the AD over either before - * or after processing. Of course this is not relevant if the user - * is doing in-place processing where src == dst. - * - * IMPORTANT NOTE AEAD requires an authentication tag (MAC). For decryption, - * the caller must concatenate the ciphertext followed by the - * authentication tag and provide the entire data stream to the - * decryption operation (i.e. the data length used for the - * initialization of the scatterlist and the data length for the - * decryption operation is identical). For encryption, however, - * the authentication tag is created while encrypting the data. - * The destination buffer must hold sufficient space for the - * ciphertext and the authentication tag while the encryption - * invocation must only point to the plaintext data size. The - * following code snippet illustrates the memory usage - * buffer = kmalloc(ptbuflen + (enc ? authsize : 0)); - * sg_init_one(&sg, buffer, ptbuflen + (enc ? authsize : 0)); - * aead_request_set_crypt(req, &sg, &sg, ptbuflen, iv); + * 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 decryption input: assoc data || ciphertext || auth tag + * - AEAD decryption output: assoc data || plaintext + * + * Albeit the kernel requires the presence of the AAD buffer, however, + * the kernel does not fill the AAD buffer in the output case. If the + * caller wants to have that data buffer filled, the caller must either + * use an in-place cipher operation (i.e. same memory location for + * input/output memory location). */ static inline void aead_request_set_crypt(struct aead_request *req, struct scatterlist *src, diff --git a/include/crypto/dh.h b/include/crypto/dh.h index 5102a8f282e6..6b424ad3482e 100644 --- a/include/crypto/dh.h +++ b/include/crypto/dh.h @@ -13,6 +13,27 @@ #ifndef _CRYPTO_DH_ #define _CRYPTO_DH_ +/** + * DOC: DH Helper Functions + * + * To use DH with the KPP cipher API, the following data structure and + * functions should be used. + * + * To use DH with KPP, the following functions should be used to operate on + * a DH private key. The packet private key that can be set with + * the KPP API function call of crypto_kpp_set_secret. + */ + +/** + * struct dh - define a DH private key + * + * @key: Private DH key + * @p: Diffie-Hellman parameter P + * @g: Diffie-Hellman generator G + * @key_size: Size of the private DH key + * @p_size: Size of DH parameter P + * @g_size: Size of DH generator G + */ struct dh { void *key; void *p; @@ -22,8 +43,45 @@ struct dh { unsigned int g_size; }; +/** + * crypto_dh_key_len() - Obtain the size of the private DH key + * @params: private DH key + * + * This function returns the packet DH key size. A caller can use that + * with the provided DH private key reference to obtain the required + * memory size to hold a packet key. + * + * Return: size of the key in bytes + */ int crypto_dh_key_len(const struct dh *params); + +/** + * crypto_dh_encode_key() - encode the private key + * @buf: Buffer allocated by the caller to hold the packet DH + * private key. The buffer should be at least crypto_dh_key_len + * bytes in size. + * @len: Length of the packet private key buffer + * @params: Buffer with the caller-specified private key + * + * The DH implementations operate on a packet representation of the private + * key. + * + * Return: -EINVAL if buffer has insufficient size, 0 on success + */ int crypto_dh_encode_key(char *buf, unsigned int len, const struct dh *params); + +/** + * crypto_dh_decode_key() - decode a private key + * @buf: Buffer holding a packet key that should be decoded + * @len: Lenth of the packet private key buffer + * @params: Buffer allocated by the caller that is filled with the + * unpacket DH private key. + * + * The unpacking obtains the private key by pointing @p to the correct location + * in @buf. Thus, both pointers refer to the same memory. + * + * Return: -EINVAL if buffer has insufficient size, 0 on success + */ int crypto_dh_decode_key(const char *buf, unsigned int len, struct dh *params); #endif diff --git a/include/crypto/ecdh.h b/include/crypto/ecdh.h index 84bad548d194..03a64f62ba7a 100644 --- a/include/crypto/ecdh.h +++ b/include/crypto/ecdh.h @@ -13,18 +13,76 @@ #ifndef _CRYPTO_ECDH_ #define _CRYPTO_ECDH_ +/** + * DOC: ECDH Helper Functions + * + * To use ECDH with the KPP cipher API, the following data structure and + * functions should be used. + * + * The ECC curves known to the ECDH implementation are specified in this + * header file. + * + * To use ECDH with KPP, the following functions should be used to operate on + * an ECDH private key. The packet private key that can be set with + * the KPP API function call of crypto_kpp_set_secret. + */ + /* Curves IDs */ #define ECC_CURVE_NIST_P192 0x0001 #define ECC_CURVE_NIST_P256 0x0002 +/** + * struct ecdh - define an ECDH private key + * + * @curve_id: ECC curve the key is based on. + * @key: Private ECDH key + * @key_size: Size of the private ECDH key + */ struct ecdh { unsigned short curve_id; char *key; unsigned short key_size; }; +/** + * crypto_ecdh_key_len() - Obtain the size of the private ECDH key + * @params: private ECDH key + * + * This function returns the packet ECDH key size. A caller can use that + * with the provided ECDH private key reference to obtain the required + * memory size to hold a packet key. + * + * Return: size of the key in bytes + */ int crypto_ecdh_key_len(const struct ecdh *params); + +/** + * crypto_ecdh_encode_key() - encode the private key + * @buf: Buffer allocated by the caller to hold the packet ECDH + * private key. The buffer should be at least crypto_ecdh_key_len + * bytes in size. + * @len: Length of the packet private key buffer + * @p: Buffer with the caller-specified private key + * + * The ECDH implementations operate on a packet representation of the private + * key. + * + * Return: -EINVAL if buffer has insufficient size, 0 on success + */ int crypto_ecdh_encode_key(char *buf, unsigned int len, const struct ecdh *p); + +/** + * crypto_ecdh_decode_key() - decode a private key + * @buf: Buffer holding a packet key that should be decoded + * @len: Lenth of the packet private key buffer + * @p: Buffer allocated by the caller that is filled with the + * unpacket ECDH private key. + * + * The unpacking obtains the private key by pointing @p to the correct location + * in @buf. Thus, both pointers refer to the same memory. + * + * Return: -EINVAL if buffer has insufficient size, 0 on success + */ int crypto_ecdh_decode_key(const char *buf, unsigned int len, struct ecdh *p); #endif diff --git a/include/crypto/hash.h b/include/crypto/hash.h index 26605888a199..216a2b876147 100644 --- a/include/crypto/hash.h +++ b/include/crypto/hash.h @@ -605,7 +605,7 @@ static inline struct ahash_request *ahash_request_cast( * the cipher operation completes. * * The callback function is registered with the &ahash_request handle and - * must comply with the following template + * must comply with the following template:: * * void callback_function(struct crypto_async_request *req, int error) */ diff --git a/include/crypto/kpp.h b/include/crypto/kpp.h index 30791f75c180..4307a2f2365f 100644 --- a/include/crypto/kpp.h +++ b/include/crypto/kpp.h @@ -71,7 +71,7 @@ struct crypto_kpp { * * @reqsize: Request context size required by algorithm * implementation - * @base Common crypto API algorithm data structure + * @base: Common crypto API algorithm data structure */ struct kpp_alg { int (*set_secret)(struct crypto_kpp *tfm, void *buffer, @@ -89,7 +89,7 @@ struct kpp_alg { }; /** - * DOC: Generic Key-agreement Protocol Primitevs API + * DOC: Generic Key-agreement Protocol Primitives API * * The KPP API is used with the algorithm type * CRYPTO_ALG_TYPE_KPP (listed as type "kpp" in /proc/crypto) @@ -264,6 +264,12 @@ struct kpp_secret { * Function invokes the specific kpp operation for a given alg. * * @tfm: tfm handle + * @buffer: Buffer holding the packet representation of the private + * key. The structure of the packet key depends on the particular + * KPP implementation. Packing and unpacking helpers are provided + * for ECDH and DH (see the respective header files for those + * implementations). + * @len: Length of the packet private key buffer. * * Return: zero on success; error code in case of error */ @@ -279,7 +285,10 @@ static inline int crypto_kpp_set_secret(struct crypto_kpp *tfm, void *buffer, * crypto_kpp_generate_public_key() - Invoke kpp operation * * Function invokes the specific kpp operation for generating the public part - * for a given kpp algorithm + * for a given kpp algorithm. + * + * To generate a private key, the caller should use a random number generator. + * The output of the requested length serves as the private key. * * @req: kpp key request * diff --git a/include/crypto/skcipher.h b/include/crypto/skcipher.h index cc4d98a7892e..750b14f1ada4 100644 --- a/include/crypto/skcipher.h +++ b/include/crypto/skcipher.h @@ -516,7 +516,7 @@ static inline void skcipher_request_zero(struct skcipher_request *req) * skcipher_request_set_callback() - set asynchronous callback function * @req: request handle * @flags: specify zero or an ORing of the flags - * CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and + * CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and * increase the wait queue beyond the initial maximum size; * CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep * @compl: callback function pointer to be registered with the request handle @@ -533,7 +533,7 @@ static inline void skcipher_request_zero(struct skcipher_request *req) * cipher operation completes. * * The callback function is registered with the skcipher_request handle and - * must comply with the following template + * must comply with the following template:: * * void callback_function(struct crypto_async_request *req, int error) */ |