/* This file is part of GNUnet. (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2012 Christian Grothoff (and other contributing authors) GNUnet 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, or (at your option) any later version. GNUnet is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNUnet; see the file COPYING. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /** * @file include/gnunet_crypto_lib.h * @brief cryptographic primitives for GNUnet * * @author Christian Grothoff * @author Krista Bennett * @author Gerd Knorr * @author Ioana Patrascu * @author Tzvetan Horozov */ #ifndef GNUNET_CRYPTO_LIB_H #define GNUNET_CRYPTO_LIB_H #ifdef __cplusplus extern "C" { #if 0 /* keep Emacsens' auto-indent happy */ } #endif #endif #include "gnunet_common.h" #include "gnunet_scheduler_lib.h" /** * Desired quality level for cryptographic operations. */ enum GNUNET_CRYPTO_Quality { /** * No good quality of the operation is needed (i.e., * random numbers can be pseudo-random). */ GNUNET_CRYPTO_QUALITY_WEAK, /** * High-quality operations are desired. */ GNUNET_CRYPTO_QUALITY_STRONG, /** * Randomness for IVs etc. is required. */ GNUNET_CRYPTO_QUALITY_NONCE }; /** * @brief length of the sessionkey in bytes (256 BIT sessionkey) */ #define GNUNET_CRYPTO_AES_KEY_LENGTH (256/8) /** * @brief Length of RSA encrypted data (2048 bit) * * We currently do not handle encryption of data * that can not be done in a single call to the * RSA methods (read: large chunks of data). * We should never need that, as we can use * the GNUNET_CRYPTO_hash for larger pieces of data for signing, * and for encryption, we only need to encode sessionkeys! */ #define GNUNET_CRYPTO_RSA_DATA_ENCODING_LENGTH 256 /** * Length of an RSA KEY (n,e,len), 2048 bit (=256 octests) key n, 2 byte e */ #define GNUNET_CRYPTO_RSA_KEY_LENGTH 258 /** * Length of a hash value */ #define GNUNET_CRYPTO_HASH_LENGTH (512/8) /** * Maximum length of an ECC signature. * Note: round up to multiple of 8 minus 2 for alignment. */ #define GNUNET_CRYPTO_ECC_SIGNATURE_DATA_ENCODING_LENGTH 126 /** * Maximum length of the public key (q-point, Q = dP) when encoded. */ #define GNUNET_CRYPTO_ECC_MAX_PUBLIC_KEY_LENGTH 76 /** * The private information of an RSA key pair. */ struct GNUNET_CRYPTO_RsaPrivateKey; /** * The private information of an ECC private key. */ struct GNUNET_CRYPTO_EccPrivateKey; GNUNET_NETWORK_STRUCT_BEGIN /** * GNUnet mandates a certain format for the encoding * of private RSA key information that is provided * by the RSA implementations. This format is used * to serialize a private RSA key (typically when * writing it to disk). */ struct GNUNET_CRYPTO_RsaPrivateKeyBinaryEncoded { /** * Total size of the structure, in bytes, in big-endian! */ uint16_t len GNUNET_PACKED; uint16_t sizen GNUNET_PACKED; /* in big-endian! */ uint16_t sizee GNUNET_PACKED; /* in big-endian! */ uint16_t sized GNUNET_PACKED; /* in big-endian! */ uint16_t sizep GNUNET_PACKED; /* in big-endian! */ uint16_t sizeq GNUNET_PACKED; /* in big-endian! */ uint16_t sizedmp1 GNUNET_PACKED; /* in big-endian! */ uint16_t sizedmq1 GNUNET_PACKED; /* in big-endian! */ /* followed by the actual values */ }; GNUNET_NETWORK_STRUCT_END /** * @brief 0-terminated ASCII encoding of a struct GNUNET_HashCode. */ struct GNUNET_CRYPTO_HashAsciiEncoded { unsigned char encoding[104]; }; /** * @brief 0-terminated ASCII encoding of a 'struct GNUNET_ShortHashCode'. */ struct GNUNET_CRYPTO_ShortHashAsciiEncoded { unsigned char short_encoding[53]; }; /** * @brief an RSA signature */ struct GNUNET_CRYPTO_RsaSignature { unsigned char sig[GNUNET_CRYPTO_RSA_DATA_ENCODING_LENGTH]; }; GNUNET_NETWORK_STRUCT_BEGIN /** * @brief header of what an RSA signature signs * this must be followed by "size - 8" bytes of * the actual signed data */ struct GNUNET_CRYPTO_RsaSignaturePurpose { /** * How many bytes does this signature sign? * (including this purpose header); in network * byte order (!). */ uint32_t size GNUNET_PACKED; /** * What does this signature vouch for? This * must contain a GNUNET_SIGNATURE_PURPOSE_XXX * constant (from gnunet_signatures.h). In * network byte order! */ uint32_t purpose GNUNET_PACKED; }; /** * @brief A public key. */ struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded { /** * In big-endian, must be GNUNET_CRYPTO_RSA_KEY_LENGTH+4 */ uint16_t len GNUNET_PACKED; /** * Size of n in key; in big-endian! */ uint16_t sizen GNUNET_PACKED; /** * The key itself, contains n followed by e. */ unsigned char key[GNUNET_CRYPTO_RSA_KEY_LENGTH]; /** * Padding (must be 0) */ uint16_t padding GNUNET_PACKED; }; /** * RSA Encrypted data. */ struct GNUNET_CRYPTO_RsaEncryptedData { unsigned char encoding[GNUNET_CRYPTO_RSA_DATA_ENCODING_LENGTH]; }; /** * @brief header of what an ECC signature signs * this must be followed by "size - 8" bytes of * the actual signed data */ struct GNUNET_CRYPTO_EccSignaturePurpose { /** * How many bytes does this signature sign? * (including this purpose header); in network * byte order (!). */ uint32_t size GNUNET_PACKED; /** * What does this signature vouch for? This * must contain a GNUNET_SIGNATURE_PURPOSE_XXX * constant (from gnunet_signatures.h). In * network byte order! */ uint32_t purpose GNUNET_PACKED; }; /** * @brief an ECC signature */ struct GNUNET_CRYPTO_EccSignature { /** * Overall size of the signature data. */ uint16_t size; /** * S-expression, padded with zeros. */ char sexpr[GNUNET_CRYPTO_ECC_SIGNATURE_DATA_ENCODING_LENGTH]; }; /** * Public ECC key (always for NIST P-521) encoded in a format suitable * for network transmission as created using 'gcry_sexp_sprint'. */ struct GNUNET_CRYPTO_EccPublicKeyBinaryEncoded { /** * Size of the encoding, in network byte order. */ uint16_t size; /** * Actual length of the q-point binary encoding. */ uint16_t len; /** * 0-padded q-point in binary encoding (GCRYPT_MPI_FMT_USG). */ unsigned char key[GNUNET_CRYPTO_ECC_MAX_PUBLIC_KEY_LENGTH]; }; struct GNUNET_CRYPTO_EccPrivateKeyBinaryEncoded { /** * Overall size of the private key. */ uint16_t size; /* followd by S-expression, opaque to applications */ /* FIXME: consider defining padding to make this a fixed-size struct */ }; /** * @brief type for session keys */ struct GNUNET_CRYPTO_AesSessionKey { /** * Actual key. */ unsigned char key[GNUNET_CRYPTO_AES_KEY_LENGTH]; }; GNUNET_NETWORK_STRUCT_END /** * @brief IV for sym cipher * * NOTE: must be smaller (!) in size than the * struct GNUNET_HashCode. */ struct GNUNET_CRYPTO_AesInitializationVector { unsigned char iv[GNUNET_CRYPTO_AES_KEY_LENGTH / 2]; }; /** * @brief type for (message) authentication keys */ struct GNUNET_CRYPTO_AuthKey { unsigned char key[GNUNET_CRYPTO_HASH_LENGTH]; }; /* **************** Functions and Macros ************* */ /** * Seed a weak random generator. Only GNUNET_CRYPTO_QUALITY_WEAK-mode generator * can be seeded. * * @param seed the seed to use */ void GNUNET_CRYPTO_seed_weak_random (int32_t seed); /** * Perform an incremental step in a CRC16 (for TCP/IP) calculation. * * @param sum current sum, initially 0 * @param buf buffer to calculate CRC over (must be 16-bit aligned) * @param len number of bytes in hdr, must be multiple of 2 * @return updated crc sum (must be subjected to GNUNET_CRYPTO_crc16_finish to get actual crc16) */ uint32_t GNUNET_CRYPTO_crc16_step (uint32_t sum, const void *buf, size_t len); /** * Convert results from GNUNET_CRYPTO_crc16_step to final crc16. * * @param sum cummulative sum * @return crc16 value */ uint16_t GNUNET_CRYPTO_crc16_finish (uint32_t sum); /** * Calculate the checksum of a buffer in one step. * * @param buf buffer to calculate CRC over (must be 16-bit aligned) * @param len number of bytes in hdr, must be multiple of 2 * @return crc16 value */ uint16_t GNUNET_CRYPTO_crc16_n (const void *buf, size_t len); /** * Compute the CRC32 checksum for the first len * bytes of the buffer. * * @param buf the data over which we're taking the CRC * @param len the length of the buffer in bytes * @return the resulting CRC32 checksum */ int32_t GNUNET_CRYPTO_crc32_n (const void *buf, size_t len); /** * Produce a random value. * * @param mode desired quality of the random number * @param i the upper limit (exclusive) for the random number * @return a random value in the interval [0,i) (exclusive). */ uint32_t GNUNET_CRYPTO_random_u32 (enum GNUNET_CRYPTO_Quality mode, uint32_t i); /** * Random on unsigned 64-bit values. * * @param mode desired quality of the random number * @param max value returned will be in range [0,max) (exclusive) * @return random 64-bit number */ uint64_t GNUNET_CRYPTO_random_u64 (enum GNUNET_CRYPTO_Quality mode, uint64_t max); /** * Get an array with a random permutation of the * numbers 0...n-1. * @param mode GNUNET_CRYPTO_QUALITY_STRONG if the strong (but expensive) PRNG should be used, GNUNET_CRYPTO_QUALITY_WEAK otherwise * @param n the size of the array * @return the permutation array (allocated from heap) */ unsigned int * GNUNET_CRYPTO_random_permute (enum GNUNET_CRYPTO_Quality mode, unsigned int n); /** * Create a new Session key. * * @param key key to initialize */ void GNUNET_CRYPTO_aes_create_session_key (struct GNUNET_CRYPTO_AesSessionKey *key); /** * Encrypt a block with the public key of another * host that uses the same cyper. * * @param block the block to encrypt * @param len the size of the block * @param sessionkey the key used to encrypt * @param iv the initialization vector to use, use INITVALUE * for streams. * @return the size of the encrypted block, -1 for errors */ ssize_t GNUNET_CRYPTO_aes_encrypt (const void *block, size_t len, const struct GNUNET_CRYPTO_AesSessionKey *sessionkey, const struct GNUNET_CRYPTO_AesInitializationVector *iv, void *result); /** * Decrypt a given block with the sessionkey. * * @param block the data to decrypt, encoded as returned by encrypt * @param size how big is the block? * @param sessionkey the key used to decrypt * @param iv the initialization vector to use * @param result address to store the result at * @return -1 on failure, size of decrypted block on success */ ssize_t GNUNET_CRYPTO_aes_decrypt (const void *block, size_t size, const struct GNUNET_CRYPTO_AesSessionKey *sessionkey, const struct GNUNET_CRYPTO_AesInitializationVector *iv, void *result); /** * @brief Derive an IV * @param iv initialization vector * @param skey session key * @param salt salt for the derivation * @param salt_len size of the salt * @param ... pairs of void * & size_t for context chunks, terminated by NULL */ void GNUNET_CRYPTO_aes_derive_iv (struct GNUNET_CRYPTO_AesInitializationVector *iv, const struct GNUNET_CRYPTO_AesSessionKey *skey, const void *salt, size_t salt_len, ...); /** * @brief Derive an IV * @param iv initialization vector * @param skey session key * @param salt salt for the derivation * @param salt_len size of the salt * @param argp pairs of void * & size_t for context chunks, terminated by NULL */ void GNUNET_CRYPTO_aes_derive_iv_v (struct GNUNET_CRYPTO_AesInitializationVector *iv, const struct GNUNET_CRYPTO_AesSessionKey *skey, const void *salt, size_t salt_len, va_list argp); /** * Convert hash to ASCII encoding. * @param block the hash code * @param result where to store the encoding (struct GNUNET_CRYPTO_HashAsciiEncoded can be * safely cast to char*, a '\\0' termination is set). */ void GNUNET_CRYPTO_hash_to_enc (const struct GNUNET_HashCode * block, struct GNUNET_CRYPTO_HashAsciiEncoded *result); /** * Convert short hash to ASCII encoding. * * @param block the hash code * @param result where to store the encoding (struct GNUNET_CRYPTO_ShortHashAsciiEncoded can be * safely cast to char*, a '\\0' termination is set). */ void GNUNET_CRYPTO_short_hash_to_enc (const struct GNUNET_CRYPTO_ShortHashCode * block, struct GNUNET_CRYPTO_ShortHashAsciiEncoded *result); /** * Convert ASCII encoding back to a 'struct GNUNET_HashCode' * * @param enc the encoding * @param enclen number of characters in 'enc' (without 0-terminator, which can be missing) * @param result where to store the GNUNET_CRYPTO_hash code * @return GNUNET_OK on success, GNUNET_SYSERR if result has the wrong encoding */ int GNUNET_CRYPTO_hash_from_string2 (const char *enc, size_t enclen, struct GNUNET_HashCode * result); /** * Convert ASCII encoding back to a 'struct GNUNET_CRYPTO_ShortHash' * * @param enc the encoding * @param enclen number of characters in 'enc' (without 0-terminator, which can be missing) * @param result where to store the GNUNET_CRYPTO_hash code * @return GNUNET_OK on success, GNUNET_SYSERR if result has the wrong encoding */ int GNUNET_CRYPTO_short_hash_from_string2 (const char *enc, size_t enclen, struct GNUNET_CRYPTO_ShortHashCode * result); /** * Convert ASCII encoding back to struct GNUNET_HashCode * * @param enc the encoding * @param result where to store the hash code * @return GNUNET_OK on success, GNUNET_SYSERR if result has the wrong encoding */ #define GNUNET_CRYPTO_hash_from_string(enc, result) \ GNUNET_CRYPTO_hash_from_string2 (enc, strlen(enc), result) /** * Convert ASCII encoding back to a 'struct GNUNET_CRYPTO_ShortHash' * * @param enc the encoding * @param result where to store the GNUNET_CRYPTO_ShortHash * @return GNUNET_OK on success, GNUNET_SYSERR if result has the wrong encoding */ #define GNUNET_CRYPTO_short_hash_from_string(enc, result) \ GNUNET_CRYPTO_short_hash_from_string2 (enc, strlen(enc), result) /** * Compare function for ShortHashCodes, producing a total ordering * of all hashcodes. * * @param h1 some hash code * @param h2 some hash code * @return 1 if h1 > h2, -1 if h1 < h2 and 0 if h1 == h2. */ int GNUNET_CRYPTO_short_hash_cmp (const struct GNUNET_CRYPTO_ShortHashCode * h1, const struct GNUNET_CRYPTO_ShortHashCode * h2); /** * Compute the distance between 2 hashcodes. * The computation must be fast, not involve * a.a or a.e (they're used elsewhere), and * be somewhat consistent. And of course, the * result should be a positive number. * * @param a some hash code * @param b some hash code * @return number between 0 and UINT32_MAX */ uint32_t GNUNET_CRYPTO_hash_distance_u32 (const struct GNUNET_HashCode * a, const struct GNUNET_HashCode * b); /** * Compute hash of a given block. * * @param block the data to hash * @param size size of the block * @param ret pointer to where to write the hashcode */ void GNUNET_CRYPTO_hash (const void *block, size_t size, struct GNUNET_HashCode * ret); /** * Compute short (256-bit) hash of a given block. * * @param block the data to hash * @param size size of the block * @param ret pointer to where to write the hashcode */ void GNUNET_CRYPTO_short_hash (const void *block, size_t size, struct GNUNET_CRYPTO_ShortHashCode * ret); /** * Double short (256-bit) hash to create a long hash. * * @param sh short hash to double * @param dh where to store the (doubled) long hash (not really a hash) */ void GNUNET_CRYPTO_short_hash_double (const struct GNUNET_CRYPTO_ShortHashCode *sh, struct GNUNET_HashCode *dh); /** * Truncate doubled short hash back to a short hash. * * @param dh doubled short hash to reduce again * @param sh where to store the short hash * @return GNUNET_OK on success, GNUNET_SYSERR if this was not a * doubled short hash */ int GNUNET_CRYPTO_short_hash_from_truncation (const struct GNUNET_HashCode *dh, struct GNUNET_CRYPTO_ShortHashCode *sh); /** * Calculate HMAC of a message (RFC 2104) * * @param key secret key * @param plaintext input plaintext * @param plaintext_len length of plaintext * @param hmac where to store the hmac */ void GNUNET_CRYPTO_hmac (const struct GNUNET_CRYPTO_AuthKey *key, const void *plaintext, size_t plaintext_len, struct GNUNET_HashCode * hmac); /** * Function called once the hash computation over the * specified file has completed. * * @param cls closure * @param res resulting hash, NULL on error */ typedef void (*GNUNET_CRYPTO_HashCompletedCallback) (void *cls, const struct GNUNET_HashCode * res); /** * Handle to file hashing operation. */ struct GNUNET_CRYPTO_FileHashContext; /** * Compute the hash of an entire file. * * @param priority scheduling priority to use * @param filename name of file to hash * @param blocksize number of bytes to process in one task * @param callback function to call upon completion * @param callback_cls closure for callback * @return NULL on (immediate) errror */ struct GNUNET_CRYPTO_FileHashContext * GNUNET_CRYPTO_hash_file (enum GNUNET_SCHEDULER_Priority priority, const char *filename, size_t blocksize, GNUNET_CRYPTO_HashCompletedCallback callback, void *callback_cls); /** * Cancel a file hashing operation. * * @param fhc operation to cancel (callback must not yet have been invoked) */ void GNUNET_CRYPTO_hash_file_cancel (struct GNUNET_CRYPTO_FileHashContext *fhc); /** * Create a random hash code. * * @param mode desired quality level * @param result hash code that is randomized */ void GNUNET_CRYPTO_hash_create_random (enum GNUNET_CRYPTO_Quality mode, struct GNUNET_HashCode * result); /** * compute result(delta) = b - a * * @param a some hash code * @param b some hash code * @param result set to b - a */ void GNUNET_CRYPTO_hash_difference (const struct GNUNET_HashCode * a, const struct GNUNET_HashCode * b, struct GNUNET_HashCode * result); /** * compute result(b) = a + delta * * @param a some hash code * @param delta some hash code * @param result set to a + delta */ void GNUNET_CRYPTO_hash_sum (const struct GNUNET_HashCode * a, const struct GNUNET_HashCode * delta, struct GNUNET_HashCode * result); /** * compute result = a ^ b * * @param a some hash code * @param b some hash code * @param result set to a ^ b */ void GNUNET_CRYPTO_hash_xor (const struct GNUNET_HashCode * a, const struct GNUNET_HashCode * b, struct GNUNET_HashCode * result); /** * Convert a hashcode into a key. * * @param hc hash code that serves to generate the key * @param skey set to a valid session key * @param iv set to a valid initialization vector */ void GNUNET_CRYPTO_hash_to_aes_key (const struct GNUNET_HashCode * hc, struct GNUNET_CRYPTO_AesSessionKey *skey, struct GNUNET_CRYPTO_AesInitializationVector *iv); /** * Obtain a bit from a hashcode. * * @param code the GNUNET_CRYPTO_hash to index bit-wise * @param bit index into the hashcode, [0...159] * @return Bit \a bit from hashcode \a code, -1 for invalid index */ int GNUNET_CRYPTO_hash_get_bit (const struct GNUNET_HashCode * code, unsigned int bit); /** * Determine how many low order bits match in two * struct GNUNET_HashCodes. i.e. - 010011 and 011111 share * the first two lowest order bits, and therefore the * return value is two (NOT XOR distance, nor how many * bits match absolutely!). * * @param first the first hashcode * @param second the hashcode to compare first to * * @return the number of bits that match */ unsigned int GNUNET_CRYPTO_hash_matching_bits (const struct GNUNET_HashCode * first, const struct GNUNET_HashCode * second); /** * Compare function for HashCodes, producing a total ordering * of all hashcodes. * * @param h1 some hash code * @param h2 some hash code * @return 1 if h1 > h2, -1 if h1 < h2 and 0 if h1 == h2. */ int GNUNET_CRYPTO_hash_cmp (const struct GNUNET_HashCode * h1, const struct GNUNET_HashCode * h2); /** * Find out which of the two GNUNET_CRYPTO_hash codes is closer to target * in the XOR metric (Kademlia). * * @param h1 some hash code * @param h2 some hash code * @param target some hash code * @return -1 if h1 is closer, 1 if h2 is closer and 0 if h1==h2. */ int GNUNET_CRYPTO_hash_xorcmp (const struct GNUNET_HashCode * h1, const struct GNUNET_HashCode * h2, const struct GNUNET_HashCode * target); /** * @brief Derive an authentication key * @param key authentication key * @param rkey root key * @param salt salt * @param salt_len size of the salt * @param argp pair of void * & size_t for context chunks, terminated by NULL */ void GNUNET_CRYPTO_hmac_derive_key_v (struct GNUNET_CRYPTO_AuthKey *key, const struct GNUNET_CRYPTO_AesSessionKey *rkey, const void *salt, size_t salt_len, va_list argp); /** * @brief Derive an authentication key * @param key authentication key * @param rkey root key * @param salt salt * @param salt_len size of the salt * @param ... pair of void * & size_t for context chunks, terminated by NULL */ void GNUNET_CRYPTO_hmac_derive_key (struct GNUNET_CRYPTO_AuthKey *key, const struct GNUNET_CRYPTO_AesSessionKey *rkey, const void *salt, size_t salt_len, ...); /** * @brief Derive key * @param result buffer for the derived key, allocated by caller * @param out_len desired length of the derived key * @param xtr_algo hash algorithm for the extraction phase, GCRY_MD_... * @param prf_algo hash algorithm for the expansion phase, GCRY_MD_... * @param xts salt * @param xts_len length of xts * @param skm source key material * @param skm_len length of skm * @param ... pair of void * & size_t for context chunks, terminated by NULL * @return GNUNET_YES on success */ int GNUNET_CRYPTO_hkdf (void *result, size_t out_len, int xtr_algo, int prf_algo, const void *xts, size_t xts_len, const void *skm, size_t skm_len, ...); /** * @brief Derive key * @param result buffer for the derived key, allocated by caller * @param out_len desired length of the derived key * @param xtr_algo hash algorithm for the extraction phase, GCRY_MD_... * @param prf_algo hash algorithm for the expansion phase, GCRY_MD_... * @param xts salt * @param xts_len length of xts * @param skm source key material * @param skm_len length of skm * @param argp va_list of void * & size_t pairs for context chunks * @return GNUNET_YES on success */ int GNUNET_CRYPTO_hkdf_v (void *result, size_t out_len, int xtr_algo, int prf_algo, const void *xts, size_t xts_len, const void *skm, size_t skm_len, va_list argp); /** * @brief Derive key * @param result buffer for the derived key, allocated by caller * @param out_len desired length of the derived key * @param xts salt * @param xts_len length of xts * @param skm source key material * @param skm_len length of skm * @param argp va_list of void * & size_t pairs for context chunks * @return GNUNET_YES on success */ int GNUNET_CRYPTO_kdf_v (void *result, size_t out_len, const void *xts, size_t xts_len, const void *skm, size_t skm_len, va_list argp); /** * @brief Derive key * @param result buffer for the derived key, allocated by caller * @param out_len desired length of the derived key * @param xts salt * @param xts_len length of xts * @param skm source key material * @param skm_len length of skm * @param ... void * & size_t pairs for context chunks * @return GNUNET_YES on success */ int GNUNET_CRYPTO_kdf (void *result, size_t out_len, const void *xts, size_t xts_len, const void *skm, size_t skm_len, ...); /** * Convert a public key to a string. * * @param pub key to convert * @return string representing 'pub' */ char * GNUNET_CRYPTO_rsa_public_key_to_string (const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *pub); /** * Convert a string representing a public key to a public key. * * @param enc encoded public key * @param enclen number of bytes in enc (without 0-terminator) * @param pub where to store the public key * @return GNUNET_OK on success */ int GNUNET_CRYPTO_rsa_public_key_from_string (const char *enc, size_t enclen, struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *pub); /** * Encode the private key in a format suitable for * storing it into a file. * @return encoding of the private key */ struct GNUNET_CRYPTO_RsaPrivateKeyBinaryEncoded * GNUNET_CRYPTO_rsa_encode_key (const struct GNUNET_CRYPTO_RsaPrivateKey *hostkey); /** * Decode the private key from the data-format back * to the "normal", internal format. * * @param buf the buffer where the private key data is stored * @param len the length of the data in 'buffer' * @return NULL on error */ struct GNUNET_CRYPTO_RsaPrivateKey * GNUNET_CRYPTO_rsa_decode_key (const char *buf, uint16_t len); /** * Create a new private key by reading it from a file. If the * files does not exist, create a new key and write it to the * file. Caller must free return value. Note that this function * can not guarantee that another process might not be trying * the same operation on the same file at the same time. * If the contents of the file * are invalid the old file is deleted and a fresh key is * created. * * @param filename name of file to use for storage * @return new private key, NULL on error (for example, * permission denied) * @deprecated use 'GNUNET_CRYPTO_rsa_key_create_start' instead */ struct GNUNET_CRYPTO_RsaPrivateKey * GNUNET_CRYPTO_rsa_key_create_from_file (const char *filename); /** * Open existing private key file and read it. If the * file does not exist, or the contents of the file are * invalid, the function fails * Caller must free returned value. * * @return a private key, NULL on error (for example, * permission denied) or when file does not exist or contains invalid * data. */ struct GNUNET_CRYPTO_RsaPrivateKey * GNUNET_CRYPTO_rsa_key_create_from_existing_file (const char *filename); /** * Handle to cancel private key generation. */ struct GNUNET_CRYPTO_RsaKeyGenerationContext; /** * Function called upon completion of 'GNUNET_CRYPTO_rsa_key_create_async'. * * @param cls closure * @param pk NULL on error, otherwise the private key (which must be free'd by the callee) * @param emsg NULL on success, otherwise an error message */ typedef void (*GNUNET_CRYPTO_RsaKeyCallback)(void *cls, struct GNUNET_CRYPTO_RsaPrivateKey *pk, const char *emsg); /** * Create a new private key by reading it from a file. If the files * does not exist, create a new key and write it to the file. If the * contents of the file are invalid the old file is deleted and a * fresh key is created. * * @param filename name of file to use for storage * @param cont function to call when done (or on errors) * @param cont_cls closure for 'cont' * @return handle to abort operation, NULL on fatal errors (cont will not be called if NULL is returned) */ struct GNUNET_CRYPTO_RsaKeyGenerationContext * GNUNET_CRYPTO_rsa_key_create_start (const char *filename, GNUNET_CRYPTO_RsaKeyCallback cont, void *cont_cls); /** * Abort RSA key generation. * * @param gc key generation context to abort */ void GNUNET_CRYPTO_rsa_key_create_stop (struct GNUNET_CRYPTO_RsaKeyGenerationContext *gc); /** * Setup a hostkey file for a peer given the name of the * configuration file (!). This function is used so that * at a later point code can be certain that reading a * hostkey is fast (for example in time-dependent testcases). * * @param cfg_name name of the configuration file to use */ void GNUNET_CRYPTO_rsa_setup_hostkey (const char *cfg_name); /** * Deterministically (!) create a private key using only the * given HashCode as input to the PRNG. * * @param hc "random" input to PRNG * @return some private key purely dependent on input */ struct GNUNET_CRYPTO_RsaPrivateKey * GNUNET_CRYPTO_rsa_key_create_from_hash (const struct GNUNET_HashCode *hc); /** * Free memory occupied by the private key. * * @param key pointer to the memory to free */ void GNUNET_CRYPTO_rsa_key_free (struct GNUNET_CRYPTO_RsaPrivateKey *key); /** * Extract the public key of the host. * * @param priv the private key * @param pub where to write the public key */ void GNUNET_CRYPTO_rsa_key_get_public (const struct GNUNET_CRYPTO_RsaPrivateKey *priv, struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *pub); /** * Get hash of the public key that corresponds to a private key. * * @param key RSA private key * @param id buffer for hash of the public key */ void GNUNET_CRYPTO_rsa_get_public_key_hash (struct GNUNET_CRYPTO_RsaPrivateKey *key, struct GNUNET_HashCode *id); /** * Encrypt a block with the public key of another host that uses the * same cyper. * * @param block the block to encrypt * @param size the size of block * @param publicKey the encoded public key used to encrypt * @param target where to store the encrypted block * @return GNUNET_SYSERR on error, GNUNET_OK if ok */ int GNUNET_CRYPTO_rsa_encrypt (const void *block, size_t size, const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *publicKey, struct GNUNET_CRYPTO_RsaEncryptedData *target); /** * Decrypt a given block with the hostkey. * * @param key the key to use * @param block the data to decrypt, encoded as returned by encrypt, not consumed * @param result pointer to a location where the result can be stored * @param max how many bytes of a result are expected? Must be exact. * @return the size of the decrypted block (that is, size) or -1 on error */ ssize_t GNUNET_CRYPTO_rsa_decrypt (const struct GNUNET_CRYPTO_RsaPrivateKey *key, const struct GNUNET_CRYPTO_RsaEncryptedData *block, void *result, size_t max); /** * Sign a given block. * * @param key private key to use for the signing * @param purpose what to sign (size, purpose) * @param sig where to write the signature * @return GNUNET_SYSERR on error, GNUNET_OK on success */ int GNUNET_CRYPTO_rsa_sign (const struct GNUNET_CRYPTO_RsaPrivateKey *key, const struct GNUNET_CRYPTO_RsaSignaturePurpose *purpose, struct GNUNET_CRYPTO_RsaSignature *sig); /** * Verify signature. Note that the caller MUST have already * checked that "validate->size" bytes are actually available. * * @param purpose what is the purpose that validate should have? * @param validate block to validate (size, purpose, data) * @param sig signature that is being validated * @param publicKey public key of the signer * @return GNUNET_OK if ok, GNUNET_SYSERR if invalid */ int GNUNET_CRYPTO_rsa_verify (uint32_t purpose, const struct GNUNET_CRYPTO_RsaSignaturePurpose *validate, const struct GNUNET_CRYPTO_RsaSignature *sig, const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *publicKey); /** * Function called upon completion of 'GNUNET_CRYPTO_ecc_key_create_async'. * * @param cls closure * @param pk NULL on error, otherwise the private key (which must be free'd by the callee) * @param emsg NULL on success, otherwise an error message */ typedef void (*GNUNET_CRYPTO_EccKeyCallback)(void *cls, struct GNUNET_CRYPTO_EccPrivateKey *pk, const char *emsg); /** * Free memory occupied by ECC key * * @param privatekey pointer to the memory to free */ void GNUNET_CRYPTO_ecc_key_free (struct GNUNET_CRYPTO_EccPrivateKey *privatekey); /** * Extract the public key for the given private key. * * @param priv the private key * @param pub where to write the public key */ void GNUNET_CRYPTO_ecc_key_get_public (const struct GNUNET_CRYPTO_EccPrivateKey *priv, struct GNUNET_CRYPTO_EccPublicKeyBinaryEncoded *pub); /** * Convert a public key to a string. * * @param pub key to convert * @return string representing 'pub' */ char * GNUNET_CRYPTO_ecc_public_key_to_string (const struct GNUNET_CRYPTO_EccPublicKeyBinaryEncoded *pub); /** * Convert a string representing a public key to a public key. * * @param enc encoded public key * @param enclen number of bytes in enc (without 0-terminator) * @param pub where to store the public key * @return GNUNET_OK on success */ int GNUNET_CRYPTO_ecc_public_key_from_string (const char *enc, size_t enclen, struct GNUNET_CRYPTO_EccPublicKeyBinaryEncoded *pub); /** * Encode the private key in a format suitable for * storing it into a file. * * @param key key to encode * @return encoding of the private key. * The first 4 bytes give the size of the array, as usual. */ struct GNUNET_CRYPTO_EccPrivateKeyBinaryEncoded * GNUNET_CRYPTO_ecc_encode_key (const struct GNUNET_CRYPTO_EccPrivateKey *key); /** * Decode the private key from the file-format back * to the "normal", internal format. * * @param buf the buffer where the private key data is stored * @param len the length of the data in 'buffer' * @param validate GNUNET_YES to validate that the key is well-formed, * GNUNET_NO if the key comes from a totally trusted source * and validation is considered too expensive * @return NULL on error */ struct GNUNET_CRYPTO_EccPrivateKey * GNUNET_CRYPTO_ecc_decode_key (const char *buf, size_t len, int validate); /** * Create a new private key by reading it from a file. If the * files does not exist, create a new key and write it to the * file. Caller must free return value. Note that this function * can not guarantee that another process might not be trying * the same operation on the same file at the same time. * If the contents of the file * are invalid the old file is deleted and a fresh key is * created. * * @return new private key, NULL on error (for example, * permission denied) */ struct GNUNET_CRYPTO_EccPrivateKey * GNUNET_CRYPTO_ecc_key_create_from_file (const char *filename); /** * Handle to cancel private key generation and state for the * key generation operation. */ struct GNUNET_CRYPTO_EccKeyGenerationContext; /** * Create a new private key. Caller must free return value. Blocking version * (blocks to gather entropy). * * @return fresh private key */ struct GNUNET_CRYPTO_EccPrivateKey * GNUNET_CRYPTO_ecc_key_create (void); /** * Create a new private key by reading it from a file. If the files * does not exist, create a new key and write it to the file. If the * contents of the file are invalid the old file is deleted and a * fresh key is created. * * @param filename name of file to use for storage * @param cont function to call when done (or on errors) * @param cont_cls closure for 'cont' * @return handle to abort operation, NULL on fatal errors (cont will not be called if NULL is returned) */ struct GNUNET_CRYPTO_EccKeyGenerationContext * GNUNET_CRYPTO_ecc_key_create_start (const char *filename, GNUNET_CRYPTO_EccKeyCallback cont, void *cont_cls); /** * Abort ECC key generation. * * @param gc key generation context to abort */ void GNUNET_CRYPTO_ecc_key_create_stop (struct GNUNET_CRYPTO_EccKeyGenerationContext *gc); /** * Setup a hostkey file for a peer given the name of the * configuration file (!). This function is used so that * at a later point code can be certain that reading a * hostkey is fast (for example in time-dependent testcases). * * @param cfg_name name of the configuration file to use */ void GNUNET_CRYPTO_ecc_setup_hostkey (const char *cfg_name); /** * Retrieve the identity of the host's peer. * * @param cfg configuration to use * @param dst pointer to where to write the peer identity * @return GNUNET_OK on success, GNUNET_SYSERR if the identity * could not be retrieved */ int GNUNET_CRYPTO_get_host_identity (const struct GNUNET_CONFIGURATION_Handle *cfg, struct GNUNET_PeerIdentity *dst); /** * Derive key material from a public and a private ECC key. * * @param key private key to use for the ECDH (x) * @param pub public key to use for the ECDY (yG) * @param key_material where to write the key material (xyG) * @return GNUNET_SYSERR on error, GNUNET_OK on success */ int GNUNET_CRYPTO_ecc_ecdh (const struct GNUNET_CRYPTO_EccPrivateKey *key, const struct GNUNET_CRYPTO_EccPublicKeyBinaryEncoded *pub, struct GNUNET_HashCode *key_material); /** * Sign a given block. * * @param key private key to use for the signing * @param purpose what to sign (size, purpose) * @param sig where to write the signature * @return GNUNET_SYSERR on error, GNUNET_OK on success */ int GNUNET_CRYPTO_ecc_sign (const struct GNUNET_CRYPTO_EccPrivateKey *key, const struct GNUNET_CRYPTO_EccSignaturePurpose *purpose, struct GNUNET_CRYPTO_EccSignature *sig); /** * Verify signature. * * @param purpose what is the purpose that the signature should have? * @param validate block to validate (size, purpose, data) * @param sig signature that is being validated * @param publicKey public key of the signer * @returns GNUNET_OK if ok, GNUNET_SYSERR if invalid */ int GNUNET_CRYPTO_ecc_verify (uint32_t purpose, const struct GNUNET_CRYPTO_EccSignaturePurpose *validate, const struct GNUNET_CRYPTO_EccSignature *sig, const struct GNUNET_CRYPTO_EccPublicKeyBinaryEncoded *publicKey); #if 0 /* keep Emacsens' auto-indent happy */ { #endif #ifdef __cplusplus } #endif /* ifndef GNUNET_CRYPTO_LIB_H */ #endif /* end of gnunet_crypto_lib.h */