X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=crypt.h;h=85629591880ad03f2d2d010f194667be1db4c121;hp=e9657ff5c0ae2b9c5a8875ea9f37e8e145ff9f64;hb=HEAD;hpb=6eab6671f857009b6d6a2de2c2ec8187f869f705 diff --git a/crypt.h b/crypt.h index e9657ff5..5578cd56 100644 --- a/crypt.h +++ b/crypt.h @@ -1,20 +1,15 @@ -/* - * Copyright (C) 2005-2013 Andre Noll - * - * Licensed under the GPL v2. For licencing details see COPYING. - */ +/* Copyright (C) 2005 Andre Noll , see file COPYING. */ /** \file crypt.h Public crypto interface. */ +/* + * Asymmetric pubkey cryptosystem (apc). + * + * This is just RSA, but this fact is a hidden implementation detail. + */ -/* These are used to distinguish between loading of private/public key. */ - -/** The key to load is a public key. */ -#define LOAD_PUBLIC_KEY 0 -/** The key to load is a private key. */ -#define LOAD_PRIVATE_KEY 1 /** The size of the challenge sent to the client. */ -#define CHALLENGE_SIZE 64 +#define APC_CHALLENGE_SIZE 64 /** Opaque structure for public and private keys. */ struct asymmetric_key; @@ -29,7 +24,7 @@ struct asymmetric_key; * * \return The size of the encrypted data on success, negative on errors. */ -int pub_encrypt(struct asymmetric_key *pub, unsigned char *inbuf, +int apc_pub_encrypt(struct asymmetric_key *pub, unsigned char *inbuf, unsigned len, unsigned char *outbuf); /** @@ -44,29 +39,28 @@ int pub_encrypt(struct asymmetric_key *pub, unsigned char *inbuf, * * \return The size of the recovered plaintext on success, negative on errors. */ -int priv_decrypt(const char *key_file, unsigned char *outbuf, +int apc_priv_decrypt(const char *key_file, unsigned char *outbuf, unsigned char *inbuf, int inlen); /** * Read an asymmetric key from a file. * * \param key_file The file containing the key. - * \param private if non-zero, read the private key, otherwise the public key. * \param result The key structure is returned here. * - * \return The size of the key on success, negative on errors. + * \return The size of the key in bytes on success, negative on errors. */ -int get_asymmetric_key(const char *key_file, int private, - struct asymmetric_key **result); +int apc_get_pubkey(const char *key_file, struct asymmetric_key **result); /** - * Deallocate an asymmetric key structure. + * Deallocate a public key. * * \param key Pointer to the key structure to free. * - * This must be called for any key obtained by get_asymmetric_key(). + * This should be called for keys obtained by \ref apc_get_pubkey() if the key is no + * longer needed. */ -void free_asymmetric_key(struct asymmetric_key *key); +void apc_free_pubkey(struct asymmetric_key *key); /** @@ -83,17 +77,20 @@ void free_asymmetric_key(struct asymmetric_key *key); void get_random_bytes_or_die(unsigned char *buf, int num); /** - * Seed pseudo random number generators. + * Initialize the crypto backend. * - * This function seeds the PRNG used by random() with a random seed obtained - * from the crypto implementation. On errors, an error message is logged and - * the function calls exit(). + * This function initializes the crypto library and seeds the pseudo random + * number generator used by random() with a random seed obtained from the + * crypto implementation. On errors, an error message is logged and the + * function calls exit(). * * \sa \ref get_random_bytes_or_die(), srandom(3), random(3), \ref * para_random(). */ -void init_random_seed_or_die(void); +void crypt_init(void); +/** Allocate all resources of the crypto backend. */ +void crypt_shutdown(void); /** Opaque structure for stream ciphers. */ struct stream_cipher; @@ -119,16 +116,14 @@ struct stream_cipher_context { }; /** - * Allocate and initialize a stream cipher structure. + * Allocate and initialize an aes_ctr128 stream cipher structure. * * \param data The key. * \param len The size of the key. - * \param use_aes True: Use the aes_ctr128 stream cipher, false: Use RC4. * * \return A new stream cipher structure. */ -struct stream_cipher *sc_new(const unsigned char *data, int len, - bool use_aes); +struct stream_cipher *sc_new(const unsigned char *data, int len); /** * Encrypt or decrypt a buffer using a stream cipher. @@ -163,7 +158,7 @@ _static_inline_ void sc_trafo(struct iovec *src, struct iovec *dst, /** * Deallocate a stream cipher structure. * - * \param sc A stream cipher previously obtained by sc_new(). + * \param sc A stream cipher previously obtained by \ref sc_new(). */ void sc_free(struct stream_cipher *sc); @@ -193,7 +188,7 @@ void hash_function(const char *data, unsigned long len, unsigned char *hash); * will be filled by the function with the ascii representation of the hash * value given by \a hash, and a terminating \p NULL byte. */ -void hash_to_asc(unsigned char *hash, char *asc); +void hash_to_asc(const unsigned char *hash, char *asc); /** * Compare two hashes. @@ -204,4 +199,43 @@ void hash_to_asc(unsigned char *hash, char *asc); * \return 1, -1, or zero, depending on whether \a h1 is greater than, * less than or equal to h2, respectively. */ -int hash_compare(unsigned char *h1, unsigned char *h2); +int hash_compare(const unsigned char *h1, const unsigned char *h2); + +/** Size of the hash value in bytes. */ +#define HASH2_SIZE 32 + +/** + * Compute the hash2 of the given input data. + * + * \param data Pointer to the data to compute the hash value from. + * \param len The length of \a data in bytes. + * \param hash Result pointer. + * + * \a hash must point to an area at least \p HASH2_SIZE bytes large. + * + * \sa sha(3), openssl(1). + * */ +void hash2_function(const char *data, unsigned long len, unsigned char *hash); + +/** + * Convert a hash2 value to ascii format. + * + * \param hash the hash value. + * \param asc Result pointer. + * + * \a asc must point to an area of at least 2 * \p HASH2_SIZE + 1 bytes which + * will be filled by the function with the ascii representation of the hash + * value given by \a hash, and a terminating \p NULL byte. + */ +void hash2_to_asc(const unsigned char *hash, char *asc); + +/** + * Compare two version 2 hashes. + * + * \param h1 Pointer to the first hash value. + * \param h2 Pointer to the second hash value. + * + * \return 1, -1, or zero, depending on whether \a h1 is greater than, + * less than or equal to h2, respectively. + */ +int hash2_compare(const unsigned char *h1, const unsigned char *h2);