diff options
Diffstat (limited to 'include/crypto/ecdh.h')
| -rw-r--r-- | include/crypto/ecdh.h | 58 |
1 files changed, 58 insertions, 0 deletions
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 |