2 This file is part of GNUnet.
3 Copyright (C) 2001-2013 GNUnet e.V.
5 GNUnet is free software: you can redistribute it and/or modify it
6 under the terms of the GNU Affero General Public License as published
7 by the Free Software Foundation, either version 3 of the License,
8 or (at your option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Affero General Public License for more details.
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16 along with this program. If not, see <http://www.gnu.org/licenses/>.
18 SPDX-License-Identifier: AGPL3.0-or-later
22 * @file include/gnunet_crypto_lib.h
23 * @brief cryptographic primitives for GNUnet
25 * @author Christian Grothoff
26 * @author Krista Bennett
27 * @author Gerd Knorr <kraxel@bytesex.org>
28 * @author Ioana Patrascu
29 * @author Tzvetan Horozov
30 * @author Jeffrey Burdges <burdges@gnunet.org>
32 * @defgroup crypto Crypto library: cryptographic operations
33 * Provides cryptographic primitives.
35 * @see [Documentation](https://gnunet.org/crypto-api)
37 * @defgroup hash Crypto library: hash operations
38 * Provides hashing and operations on hashes.
40 * @see [Documentation](https://gnunet.org/crypto-api)
43 #ifndef GNUNET_CRYPTO_LIB_H
44 #define GNUNET_CRYPTO_LIB_H
48 #if 0 /* keep Emacsens' auto-indent happy */
55 * The identity of the host (wraps the signing key of the peer).
57 struct GNUNET_PeerIdentity;
59 #include "gnunet_common.h"
64 * Maximum length of an ECC signature.
65 * Note: round up to multiple of 8 minus 2 for alignment.
67 #define GNUNET_CRYPTO_ECC_SIGNATURE_DATA_ENCODING_LENGTH 126
71 * Desired quality level for random numbers.
74 enum GNUNET_CRYPTO_Quality
77 * No good quality of the operation is needed (i.e.,
78 * random numbers can be pseudo-random).
81 GNUNET_CRYPTO_QUALITY_WEAK,
84 * High-quality operations are desired.
87 GNUNET_CRYPTO_QUALITY_STRONG,
90 * Randomness for IVs etc. is required.
93 GNUNET_CRYPTO_QUALITY_NONCE
98 * @brief length of the sessionkey in bytes (256 BIT sessionkey)
100 #define GNUNET_CRYPTO_AES_KEY_LENGTH (256 / 8)
103 * Length of a hash value
105 #define GNUNET_CRYPTO_HASH_LENGTH (512 / 8)
108 * How many characters (without 0-terminator) are our ASCII-encoded
109 * public keys (ECDSA/EDDSA/ECDHE).
111 #define GNUNET_CRYPTO_PKEY_ASCII_LENGTH 52
114 * @brief 0-terminated ASCII encoding of a struct GNUNET_HashCode.
116 struct GNUNET_CRYPTO_HashAsciiEncoded
118 unsigned char encoding[104];
122 GNUNET_NETWORK_STRUCT_BEGIN
126 * @brief header of what an ECC signature signs
127 * this must be followed by "size - 8" bytes of
128 * the actual signed data
130 struct GNUNET_CRYPTO_EccSignaturePurpose
133 * How many bytes does this signature sign?
134 * (including this purpose header); in network
137 uint32_t size GNUNET_PACKED;
140 * What does this signature vouch for? This
141 * must contain a GNUNET_SIGNATURE_PURPOSE_XXX
142 * constant (from gnunet_signatures.h). In
143 * network byte order!
145 uint32_t purpose GNUNET_PACKED;
150 * @brief an ECC signature using EdDSA.
151 * See cr.yp.to/papers.html#ed25519
153 struct GNUNET_CRYPTO_EddsaSignature
158 unsigned char r[256 / 8];
163 unsigned char s[256 / 8];
168 * @brief an ECC signature using ECDSA
170 struct GNUNET_CRYPTO_EcdsaSignature
175 unsigned char r[256 / 8];
180 unsigned char s[256 / 8];
185 * Public ECC key (always for curve Ed25519) encoded in a format
186 * suitable for network transmission and EdDSA signatures.
188 struct GNUNET_CRYPTO_EddsaPublicKey
191 * Point Q consists of a y-value mod p (256 bits); the x-value is
192 * always positive. The point is stored in Ed25519 standard
195 unsigned char q_y[256 / 8];
200 * Public ECC key (always for Curve25519) encoded in a format suitable
201 * for network transmission and ECDSA signatures.
203 struct GNUNET_CRYPTO_EcdsaPublicKey
206 * Q consists of an x- and a y-value, each mod p (256 bits), given
207 * here in affine coordinates and Ed25519 standard compact format.
209 unsigned char q_y[256 / 8];
214 * The identity of the host (wraps the signing key of the peer).
216 struct GNUNET_PeerIdentity
218 struct GNUNET_CRYPTO_EddsaPublicKey public_key;
223 * Public ECC key (always for Curve25519) encoded in a format suitable
224 * for network transmission and encryption (ECDH),
225 * See http://cr.yp.to/ecdh.html
227 struct GNUNET_CRYPTO_EcdhePublicKey
230 * Q consists of an x- and a y-value, each mod p (256 bits), given
231 * here in affine coordinates and Ed25519 standard compact format.
233 unsigned char q_y[256 / 8];
238 * Private ECC key encoded for transmission. To be used only for ECDH
239 * key exchange (ECDHE to be precise).
241 struct GNUNET_CRYPTO_EcdhePrivateKey
244 * d is a value mod n, where n has at most 256 bits.
246 unsigned char d[256 / 8];
250 * Private ECC key encoded for transmission. To be used only for ECDSA
253 struct GNUNET_CRYPTO_EcdsaPrivateKey
256 * d is a value mod n, where n has at most 256 bits.
258 unsigned char d[256 / 8];
262 * Private ECC key encoded for transmission. To be used only for EdDSA
265 struct GNUNET_CRYPTO_EddsaPrivateKey
268 * d is a value mod n, where n has at most 256 bits.
270 unsigned char d[256 / 8];
275 * @brief type for session keys
277 struct GNUNET_CRYPTO_SymmetricSessionKey
280 * Actual key for AES.
282 unsigned char aes_key[GNUNET_CRYPTO_AES_KEY_LENGTH];
285 * Actual key for TwoFish.
287 unsigned char twofish_key[GNUNET_CRYPTO_AES_KEY_LENGTH];
290 GNUNET_NETWORK_STRUCT_END
293 * @brief IV for sym cipher
295 * NOTE: must be smaller (!) in size than the
296 * `struct GNUNET_HashCode`.
298 struct GNUNET_CRYPTO_SymmetricInitializationVector
300 unsigned char aes_iv[GNUNET_CRYPTO_AES_KEY_LENGTH / 2];
302 unsigned char twofish_iv[GNUNET_CRYPTO_AES_KEY_LENGTH / 2];
307 * @brief type for (message) authentication keys
309 struct GNUNET_CRYPTO_AuthKey
311 unsigned char key[GNUNET_CRYPTO_HASH_LENGTH];
316 * Size of paillier plain texts and public keys.
317 * Private keys and ciphertexts are twice this size.
319 #define GNUNET_CRYPTO_PAILLIER_BITS 2048
323 * Paillier public key.
325 struct GNUNET_CRYPTO_PaillierPublicKey
330 unsigned char n[GNUNET_CRYPTO_PAILLIER_BITS / 8];
335 * Paillier private key.
337 struct GNUNET_CRYPTO_PaillierPrivateKey
340 * Lambda-component of the private key.
342 unsigned char lambda[GNUNET_CRYPTO_PAILLIER_BITS / 8];
344 * Mu-component of the private key.
346 unsigned char mu[GNUNET_CRYPTO_PAILLIER_BITS / 8];
351 * Paillier ciphertext.
353 struct GNUNET_CRYPTO_PaillierCiphertext
356 * Guaranteed minimum number of homomorphic operations with this ciphertext,
357 * in network byte order (NBO).
359 int32_t remaining_ops GNUNET_PACKED;
362 * The bits of the ciphertext.
364 unsigned char bits[GNUNET_CRYPTO_PAILLIER_BITS * 2 / 8];
368 /* **************** Functions and Macros ************* */
372 * Seed a weak random generator. Only #GNUNET_CRYPTO_QUALITY_WEAK-mode generator
375 * @param seed the seed to use
378 GNUNET_CRYPTO_seed_weak_random (int32_t seed);
383 * Calculate the checksum of a buffer in one step.
385 * @param buf buffer to calculate CRC over
386 * @param len number of bytes in @a buf
390 GNUNET_CRYPTO_crc8_n (const void *buf, size_t len);
394 * Perform an incremental step in a CRC16 (for TCP/IP) calculation.
396 * @param sum current sum, initially 0
397 * @param buf buffer to calculate CRC over (must be 16-bit aligned)
398 * @param len number of bytes in @a buf, must be multiple of 2
399 * @return updated crc sum (must be subjected to #GNUNET_CRYPTO_crc16_finish to get actual crc16)
402 GNUNET_CRYPTO_crc16_step (uint32_t sum, const void *buf, size_t len);
406 * Convert results from GNUNET_CRYPTO_crc16_step to final crc16.
408 * @param sum cummulative sum
409 * @return crc16 value
412 GNUNET_CRYPTO_crc16_finish (uint32_t sum);
417 * Calculate the checksum of a buffer in one step.
419 * @param buf buffer to calculate CRC over (must be 16-bit aligned)
420 * @param len number of bytes in @a buf, must be multiple of 2
421 * @return crc16 value
424 GNUNET_CRYPTO_crc16_n (const void *buf, size_t len);
429 * Compute the CRC32 checksum for the first len
430 * bytes of the buffer.
432 * @param buf the data over which we're taking the CRC
433 * @param len the length of the buffer @a buf in bytes
434 * @return the resulting CRC32 checksum
437 GNUNET_CRYPTO_crc32_n (const void *buf, size_t len);
441 * Zero out @a buffer, securely against compiler optimizations.
442 * Used to delete key material.
444 * @param buffer the buffer to zap
445 * @param length buffer length
448 GNUNET_CRYPTO_zero_keys (void *buffer, size_t length);
453 * Fill block with a random values.
455 * @param mode desired quality of the random number
456 * @param buffer the buffer to fill
457 * @param length buffer length
460 GNUNET_CRYPTO_random_block (enum GNUNET_CRYPTO_Quality mode,
466 * Produce a random value.
468 * @param mode desired quality of the random number
469 * @param i the upper limit (exclusive) for the random number
470 * @return a random value in the interval [0,@a i) (exclusive).
473 GNUNET_CRYPTO_random_u32 (enum GNUNET_CRYPTO_Quality mode, uint32_t i);
478 * Random on unsigned 64-bit values.
480 * @param mode desired quality of the random number
481 * @param max value returned will be in range [0,@a max) (exclusive)
482 * @return random 64-bit number
485 GNUNET_CRYPTO_random_u64 (enum GNUNET_CRYPTO_Quality mode, uint64_t max);
490 * Get an array with a random permutation of the
492 * @param mode #GNUNET_CRYPTO_QUALITY_STRONG if the strong (but expensive) PRNG should be used,
493 * #GNUNET_CRYPTO_QUALITY_WEAK or #GNUNET_CRYPTO_QUALITY_NONCE otherwise
494 * @param n the size of the array
495 * @return the permutation array (allocated from heap)
498 GNUNET_CRYPTO_random_permute (enum GNUNET_CRYPTO_Quality mode, unsigned int n);
503 * Create a new random session key.
505 * @param key key to initialize
508 GNUNET_CRYPTO_symmetric_create_session_key (
509 struct GNUNET_CRYPTO_SymmetricSessionKey *key);
514 * Encrypt a block using a symmetric sessionkey.
516 * @param block the block to encrypt
517 * @param size the size of the @a block
518 * @param sessionkey the key used to encrypt
519 * @param iv the initialization vector to use, use INITVALUE
521 * @return the size of the encrypted block, -1 for errors
524 GNUNET_CRYPTO_symmetric_encrypt (
527 const struct GNUNET_CRYPTO_SymmetricSessionKey *sessionkey,
528 const struct GNUNET_CRYPTO_SymmetricInitializationVector *iv,
534 * Decrypt a given block using a symmetric sessionkey.
536 * @param block the data to decrypt, encoded as returned by encrypt
537 * @param size how big is the block?
538 * @param sessionkey the key used to decrypt
539 * @param iv the initialization vector to use
540 * @param result address to store the result at
541 * @return -1 on failure, size of decrypted block on success
544 GNUNET_CRYPTO_symmetric_decrypt (
547 const struct GNUNET_CRYPTO_SymmetricSessionKey *sessionkey,
548 const struct GNUNET_CRYPTO_SymmetricInitializationVector *iv,
554 * @brief Derive an IV
555 * @param iv initialization vector
556 * @param skey session key
557 * @param salt salt for the derivation
558 * @param salt_len size of the @a salt
559 * @param ... pairs of void * & size_t for context chunks, terminated by NULL
562 GNUNET_CRYPTO_symmetric_derive_iv (
563 struct GNUNET_CRYPTO_SymmetricInitializationVector *iv,
564 const struct GNUNET_CRYPTO_SymmetricSessionKey *skey,
571 * @brief Derive an IV
572 * @param iv initialization vector
573 * @param skey session key
574 * @param salt salt for the derivation
575 * @param salt_len size of the @a salt
576 * @param argp pairs of void * & size_t for context chunks, terminated by NULL
579 GNUNET_CRYPTO_symmetric_derive_iv_v (
580 struct GNUNET_CRYPTO_SymmetricInitializationVector *iv,
581 const struct GNUNET_CRYPTO_SymmetricSessionKey *skey,
589 * Convert hash to ASCII encoding.
590 * @param block the hash code
591 * @param result where to store the encoding (struct GNUNET_CRYPTO_HashAsciiEncoded can be
592 * safely cast to char*, a '\\0' termination is set).
595 GNUNET_CRYPTO_hash_to_enc (const struct GNUNET_HashCode *block,
596 struct GNUNET_CRYPTO_HashAsciiEncoded *result);
601 * Convert ASCII encoding back to a 'struct GNUNET_HashCode'
603 * @param enc the encoding
604 * @param enclen number of characters in @a enc (without 0-terminator, which can be missing)
605 * @param result where to store the hash code
606 * @return #GNUNET_OK on success, #GNUNET_SYSERR if result has the wrong encoding
609 GNUNET_CRYPTO_hash_from_string2 (const char *enc,
611 struct GNUNET_HashCode *result);
616 * Convert ASCII encoding back to `struct GNUNET_HashCode`
618 * @param enc the encoding
619 * @param result where to store the hash code
620 * @return #GNUNET_OK on success, #GNUNET_SYSERR if result has the wrong encoding
622 #define GNUNET_CRYPTO_hash_from_string(enc, result) \
623 GNUNET_CRYPTO_hash_from_string2 (enc, strlen (enc), result)
629 * Compute the distance between 2 hashcodes. The
630 * computation must be fast, not involve @a a[0] or @a a[4] (they're used
631 * elsewhere), and be somewhat consistent. And of course, the result
632 * should be a positive number.
634 * @param a some hash code
635 * @param b some hash code
636 * @return number between 0 and UINT32_MAX
639 GNUNET_CRYPTO_hash_distance_u32 (const struct GNUNET_HashCode *a,
640 const struct GNUNET_HashCode *b);
645 * Compute hash of a given block.
647 * @param block the data to hash
648 * @param size size of the @a block
649 * @param ret pointer to where to write the hashcode
652 GNUNET_CRYPTO_hash (const void *block,
654 struct GNUNET_HashCode *ret);
658 * Calculate the 'proof-of-work' hash (an expensive hash).
660 * @param salt salt to use in pow calculation
661 * @param buf data to hash
662 * @param buf_len number of bytes in @a buf
663 * @param result where to write the resulting hash
666 GNUNET_CRYPTO_pow_hash (const char *salt,
669 struct GNUNET_HashCode *result);
673 * Context for cummulative hashing.
675 struct GNUNET_HashContext;
679 * Start incremental hashing operation.
681 * @return context for incremental hash computation
683 struct GNUNET_HashContext *
684 GNUNET_CRYPTO_hash_context_start (void);
688 * Add data to be hashed.
690 * @param hc cummulative hash context
691 * @param buf data to add
692 * @param size number of bytes in @a buf
695 GNUNET_CRYPTO_hash_context_read (struct GNUNET_HashContext *hc,
701 * Finish the hash computation.
703 * @param hc hash context to use, is freed in the process
704 * @param r_hash where to write the latest / final hash code
707 GNUNET_CRYPTO_hash_context_finish (struct GNUNET_HashContext *hc,
708 struct GNUNET_HashCode *r_hash);
712 * Abort hashing, do not bother calculating final result.
714 * @param hc hash context to destroy
717 GNUNET_CRYPTO_hash_context_abort (struct GNUNET_HashContext *hc);
721 * Calculate HMAC of a message (RFC 2104)
722 * TODO: Shouldn' this be the standard hmac function and
723 * the above be renamed?
725 * @param key secret key
726 * @param key_len secret key length
727 * @param plaintext input plaintext
728 * @param plaintext_len length of @a plaintext
729 * @param hmac where to store the hmac
732 GNUNET_CRYPTO_hmac_raw (const void *key,
734 const void *plaintext,
735 size_t plaintext_len,
736 struct GNUNET_HashCode *hmac);
741 * Calculate HMAC of a message (RFC 2104)
743 * @param key secret key
744 * @param plaintext input plaintext
745 * @param plaintext_len length of @a plaintext
746 * @param hmac where to store the hmac
749 GNUNET_CRYPTO_hmac (const struct GNUNET_CRYPTO_AuthKey *key,
750 const void *plaintext,
751 size_t plaintext_len,
752 struct GNUNET_HashCode *hmac);
756 * Function called once the hash computation over the
757 * specified file has completed.
760 * @param res resulting hash, NULL on error
762 typedef void (*GNUNET_CRYPTO_HashCompletedCallback) (
764 const struct GNUNET_HashCode *res);
768 * Handle to file hashing operation.
770 struct GNUNET_CRYPTO_FileHashContext;
775 * Compute the hash of an entire file.
777 * @param priority scheduling priority to use
778 * @param filename name of file to hash
779 * @param blocksize number of bytes to process in one task
780 * @param callback function to call upon completion
781 * @param callback_cls closure for @a callback
782 * @return NULL on (immediate) errror
784 struct GNUNET_CRYPTO_FileHashContext *
785 GNUNET_CRYPTO_hash_file (enum GNUNET_SCHEDULER_Priority priority,
786 const char *filename,
788 GNUNET_CRYPTO_HashCompletedCallback callback,
793 * Cancel a file hashing operation.
795 * @param fhc operation to cancel (callback must not yet have been invoked)
798 GNUNET_CRYPTO_hash_file_cancel (struct GNUNET_CRYPTO_FileHashContext *fhc);
803 * Create a random hash code.
805 * @param mode desired quality level
806 * @param result hash code that is randomized
809 GNUNET_CRYPTO_hash_create_random (enum GNUNET_CRYPTO_Quality mode,
810 struct GNUNET_HashCode *result);
815 * compute @a result = @a b - @a a
817 * @param a some hash code
818 * @param b some hash code
819 * @param result set to @a b - @a a
822 GNUNET_CRYPTO_hash_difference (const struct GNUNET_HashCode *a,
823 const struct GNUNET_HashCode *b,
824 struct GNUNET_HashCode *result);
829 * compute @a result = @a a + @a delta
831 * @param a some hash code
832 * @param delta some hash code
833 * @param result set to @a a + @a delta
836 GNUNET_CRYPTO_hash_sum (const struct GNUNET_HashCode *a,
837 const struct GNUNET_HashCode *delta,
838 struct GNUNET_HashCode *result);
843 * compute result = a ^ b
845 * @param a some hash code
846 * @param b some hash code
847 * @param result set to @a a ^ @a b
850 GNUNET_CRYPTO_hash_xor (const struct GNUNET_HashCode *a,
851 const struct GNUNET_HashCode *b,
852 struct GNUNET_HashCode *result);
857 * Convert a hashcode into a key.
859 * @param hc hash code that serves to generate the key
860 * @param skey set to a valid session key
861 * @param iv set to a valid initialization vector
864 GNUNET_CRYPTO_hash_to_aes_key (
865 const struct GNUNET_HashCode *hc,
866 struct GNUNET_CRYPTO_SymmetricSessionKey *skey,
867 struct GNUNET_CRYPTO_SymmetricInitializationVector *iv);
872 * Obtain a bit from a hashcode.
874 * @param code the `struct GNUNET_HashCode` to index bit-wise
875 * @param bit index into the hashcode, [0...159]
876 * @return Bit \a bit from hashcode \a code, -1 for invalid index
879 GNUNET_CRYPTO_hash_get_bit (const struct GNUNET_HashCode *code,
885 * Determine how many low order bits match in two
886 * `struct GNUNET_HashCodes`. i.e. - 010011 and 011111 share
887 * the first two lowest order bits, and therefore the
888 * return value is two (NOT XOR distance, nor how many
889 * bits match absolutely!).
891 * @param first the first hashcode
892 * @param second the hashcode to compare first to
893 * @return the number of bits that match
896 GNUNET_CRYPTO_hash_matching_bits (const struct GNUNET_HashCode *first,
897 const struct GNUNET_HashCode *second);
902 * Compare function for HashCodes, producing a total ordering
905 * @param h1 some hash code
906 * @param h2 some hash code
907 * @return 1 if @a h1 > @a h2, -1 if @a h1 < @a h2 and 0 if @a h1 == @a h2.
910 GNUNET_CRYPTO_hash_cmp (const struct GNUNET_HashCode *h1,
911 const struct GNUNET_HashCode *h2);
916 * Find out which of the two GNUNET_CRYPTO_hash codes is closer to target
917 * in the XOR metric (Kademlia).
919 * @param h1 some hash code
920 * @param h2 some hash code
921 * @param target some hash code
922 * @return -1 if @a h1 is closer, 1 if @a h2 is closer and 0 if @a h1== @a h2.
925 GNUNET_CRYPTO_hash_xorcmp (const struct GNUNET_HashCode *h1,
926 const struct GNUNET_HashCode *h2,
927 const struct GNUNET_HashCode *target);
932 * @brief Derive an authentication key
933 * @param key authentication key
934 * @param rkey root key
936 * @param salt_len size of the salt
937 * @param argp pair of void * & size_t for context chunks, terminated by NULL
940 GNUNET_CRYPTO_hmac_derive_key_v (
941 struct GNUNET_CRYPTO_AuthKey *key,
942 const struct GNUNET_CRYPTO_SymmetricSessionKey *rkey,
950 * @brief Derive an authentication key
951 * @param key authentication key
952 * @param rkey root key
954 * @param salt_len size of the salt
955 * @param ... pair of void * & size_t for context chunks, terminated by NULL
958 GNUNET_CRYPTO_hmac_derive_key (
959 struct GNUNET_CRYPTO_AuthKey *key,
960 const struct GNUNET_CRYPTO_SymmetricSessionKey *rkey,
969 * @param result buffer for the derived key, allocated by caller
970 * @param out_len desired length of the derived key
971 * @param xtr_algo hash algorithm for the extraction phase, GCRY_MD_...
972 * @param prf_algo hash algorithm for the expansion phase, GCRY_MD_...
974 * @param xts_len length of @a xts
975 * @param skm source key material
976 * @param skm_len length of @a skm
977 * @param ... pair of void * & size_t for context chunks, terminated by NULL
978 * @return #GNUNET_YES on success
981 GNUNET_CRYPTO_hkdf (void *result,
995 * @param result buffer for the derived key, allocated by caller
996 * @param out_len desired length of the derived key
997 * @param xtr_algo hash algorithm for the extraction phase, GCRY_MD_...
998 * @param prf_algo hash algorithm for the expansion phase, GCRY_MD_...
1000 * @param xts_len length of @a xts
1001 * @param skm source key material
1002 * @param skm_len length of @a skm
1003 * @param argp va_list of void * & size_t pairs for context chunks
1004 * @return #GNUNET_YES on success
1007 GNUNET_CRYPTO_hkdf_v (void *result,
1020 * @param result buffer for the derived key, allocated by caller
1021 * @param out_len desired length of the derived key
1023 * @param xts_len length of @a xts
1024 * @param skm source key material
1025 * @param skm_len length of @a skm
1026 * @param argp va_list of void * & size_t pairs for context chunks
1027 * @return #GNUNET_YES on success
1030 GNUNET_CRYPTO_kdf_v (void *result,
1040 * Deterministically generate a pseudo-random number uniformly from the
1041 * integers modulo a libgcrypt mpi.
1043 * @param[out] r MPI value set to the FDH
1044 * @param n MPI to work modulo
1046 * @param xts_len length of @a xts
1047 * @param skm source key material
1048 * @param skm_len length of @a skm
1049 * @param ctx context string
1052 GNUNET_CRYPTO_kdf_mod_mpi (gcry_mpi_t *r,
1064 * @param result buffer for the derived key, allocated by caller
1065 * @param out_len desired length of the derived key
1067 * @param xts_len length of @a xts
1068 * @param skm source key material
1069 * @param skm_len length of @a skm
1070 * @param ... void * & size_t pairs for context chunks
1071 * @return #GNUNET_YES on success
1074 GNUNET_CRYPTO_kdf (void *result,
1085 * Extract the public key for the given private key.
1087 * @param priv the private key
1088 * @param pub where to write the public key
1091 GNUNET_CRYPTO_ecdsa_key_get_public (
1092 const struct GNUNET_CRYPTO_EcdsaPrivateKey *priv,
1093 struct GNUNET_CRYPTO_EcdsaPublicKey *pub);
1097 * Extract the public key for the given private key.
1099 * @param priv the private key
1100 * @param pub where to write the public key
1103 GNUNET_CRYPTO_eddsa_key_get_public (
1104 const struct GNUNET_CRYPTO_EddsaPrivateKey *priv,
1105 struct GNUNET_CRYPTO_EddsaPublicKey *pub);
1110 * Extract the public key for the given private key.
1112 * @param priv the private key
1113 * @param pub where to write the public key
1116 GNUNET_CRYPTO_ecdhe_key_get_public (
1117 const struct GNUNET_CRYPTO_EcdhePrivateKey *priv,
1118 struct GNUNET_CRYPTO_EcdhePublicKey *pub);
1122 * Convert a public key to a string.
1124 * @param pub key to convert
1125 * @return string representing @a pub
1128 GNUNET_CRYPTO_ecdsa_public_key_to_string (
1129 const struct GNUNET_CRYPTO_EcdsaPublicKey *pub);
1132 * Convert a private key to a string.
1134 * @param priv key to convert
1135 * @return string representing @a priv
1138 GNUNET_CRYPTO_ecdsa_private_key_to_string (
1139 const struct GNUNET_CRYPTO_EcdsaPrivateKey *priv);
1143 * Convert a private key to a string.
1145 * @param priv key to convert
1146 * @return string representing @a pub
1149 GNUNET_CRYPTO_eddsa_private_key_to_string (
1150 const struct GNUNET_CRYPTO_EddsaPrivateKey *priv);
1154 * Convert a public key to a string.
1156 * @param pub key to convert
1157 * @return string representing @a pub
1160 GNUNET_CRYPTO_eddsa_public_key_to_string (
1161 const struct GNUNET_CRYPTO_EddsaPublicKey *pub);
1165 * Convert a string representing a public key to a public key.
1167 * @param enc encoded public key
1168 * @param enclen number of bytes in @a enc (without 0-terminator)
1169 * @param pub where to store the public key
1170 * @return #GNUNET_OK on success
1173 GNUNET_CRYPTO_ecdsa_public_key_from_string (
1176 struct GNUNET_CRYPTO_EcdsaPublicKey *pub);
1180 * Convert a string representing a private key to a private key.
1182 * @param enc encoded public key
1183 * @param enclen number of bytes in @a enc (without 0-terminator)
1184 * @param priv where to store the private key
1185 * @return #GNUNET_OK on success
1188 GNUNET_CRYPTO_eddsa_private_key_from_string (
1191 struct GNUNET_CRYPTO_EddsaPrivateKey *pub);
1195 * Convert a string representing a public key to a public key.
1197 * @param enc encoded public key
1198 * @param enclen number of bytes in @a enc (without 0-terminator)
1199 * @param pub where to store the public key
1200 * @return #GNUNET_OK on success
1203 GNUNET_CRYPTO_eddsa_public_key_from_string (
1206 struct GNUNET_CRYPTO_EddsaPublicKey *pub);
1211 * Create a new private key by reading it from a file. If the
1212 * files does not exist, create a new key and write it to the
1213 * file. Caller must free return value. Note that this function
1214 * can not guarantee that another process might not be trying
1215 * the same operation on the same file at the same time.
1216 * If the contents of the file
1217 * are invalid the old file is deleted and a fresh key is
1220 * @param filename name of file to use to store the key
1221 * @return new private key, NULL on error (for example,
1222 * permission denied); free using #GNUNET_free
1224 struct GNUNET_CRYPTO_EcdsaPrivateKey *
1225 GNUNET_CRYPTO_ecdsa_key_create_from_file (const char *filename);
1230 * Create a new private key by reading it from a file. If the
1231 * files does not exist, create a new key and write it to the
1232 * file. Caller must free return value. Note that this function
1233 * can not guarantee that another process might not be trying
1234 * the same operation on the same file at the same time.
1235 * If the contents of the file
1236 * are invalid the old file is deleted and a fresh key is
1239 * @param filename name of file to use to store the key
1240 * @return new private key, NULL on error (for example,
1241 * permission denied); free using #GNUNET_free
1243 struct GNUNET_CRYPTO_EddsaPrivateKey *
1244 GNUNET_CRYPTO_eddsa_key_create_from_file (const char *filename);
1248 * Forward declaration to simplify #include-structure.
1250 struct GNUNET_CONFIGURATION_Handle;
1255 * Create a new private key by reading our peer's key from
1256 * the file specified in the configuration.
1258 * @param cfg the configuration to use
1259 * @return new private key, NULL on error (for example,
1260 * permission denied); free using #GNUNET_free
1262 struct GNUNET_CRYPTO_EddsaPrivateKey *
1263 GNUNET_CRYPTO_eddsa_key_create_from_configuration (
1264 const struct GNUNET_CONFIGURATION_Handle *cfg);
1269 * Create a new private key. Caller must free return value.
1271 * @return fresh private key; free using #GNUNET_free
1273 struct GNUNET_CRYPTO_EcdsaPrivateKey *
1274 GNUNET_CRYPTO_ecdsa_key_create (void);
1279 * Create a new private key. Caller must free return value.
1281 * @return fresh private key; free using #GNUNET_free
1283 struct GNUNET_CRYPTO_EddsaPrivateKey *
1284 GNUNET_CRYPTO_eddsa_key_create (void);
1289 * Create a new private key. Clear with #GNUNET_CRYPTO_ecdhe_key_clear().
1291 * @param[out] pk set to fresh private key;
1292 * @return #GNUNET_OK on success, #GNUNET_SYSERR on failure
1295 GNUNET_CRYPTO_ecdhe_key_create2 (struct GNUNET_CRYPTO_EcdhePrivateKey *pk);
1300 * Create a new private key. Caller must free return value.
1302 * @return fresh private key; free using #GNUNET_free
1304 struct GNUNET_CRYPTO_EcdhePrivateKey *
1305 GNUNET_CRYPTO_ecdhe_key_create (void);
1310 * Clear memory that was used to store a private key.
1312 * @param pk location of the key
1315 GNUNET_CRYPTO_eddsa_key_clear (struct GNUNET_CRYPTO_EddsaPrivateKey *pk);
1320 * Clear memory that was used to store a private key.
1322 * @param pk location of the key
1325 GNUNET_CRYPTO_ecdsa_key_clear (struct GNUNET_CRYPTO_EcdsaPrivateKey *pk);
1330 * Clear memory that was used to store a private key.
1332 * @param pk location of the key
1335 GNUNET_CRYPTO_ecdhe_key_clear (struct GNUNET_CRYPTO_EcdhePrivateKey *pk);
1340 * Get the shared private key we use for anonymous users.
1342 * @return "anonymous" private key; do not free
1344 const struct GNUNET_CRYPTO_EcdsaPrivateKey *
1345 GNUNET_CRYPTO_ecdsa_key_get_anonymous (void);
1350 * Setup a hostkey file for a peer given the name of the
1351 * configuration file (!). This function is used so that
1352 * at a later point code can be certain that reading a
1353 * hostkey is fast (for example in time-dependent testcases).
1355 * @param cfg_name name of the configuration file to use
1358 GNUNET_CRYPTO_eddsa_setup_hostkey (const char *cfg_name);
1363 * Retrieve the identity of the host's peer.
1365 * @param cfg configuration to use
1366 * @param dst pointer to where to write the peer identity
1367 * @return #GNUNET_OK on success, #GNUNET_SYSERR if the identity
1368 * could not be retrieved
1371 GNUNET_CRYPTO_get_peer_identity (const struct GNUNET_CONFIGURATION_Handle *cfg,
1372 struct GNUNET_PeerIdentity *dst);
1376 * Internal structure used to cache pre-calculated values for DLOG calculation.
1378 struct GNUNET_CRYPTO_EccDlogContext;
1382 * Point on a curve (always for Curve25519) encoded in a format suitable
1383 * for network transmission (ECDH), see http://cr.yp.to/ecdh.html.
1385 struct GNUNET_CRYPTO_EccPoint
1388 * Q consists of an x- and a y-value, each mod p (256 bits), given
1389 * here in affine coordinates and Ed25519 standard compact format.
1391 unsigned char q_y[256 / 8];
1396 * Do pre-calculation for ECC discrete logarithm for small factors.
1398 * @param max maximum value the factor can be
1399 * @param mem memory to use (should be smaller than @a max), must not be zero.
1400 * @return NULL on error
1402 struct GNUNET_CRYPTO_EccDlogContext *
1403 GNUNET_CRYPTO_ecc_dlog_prepare (unsigned int max, unsigned int mem);
1407 * Calculate ECC discrete logarithm for small factors.
1408 * Opposite of #GNUNET_CRYPTO_ecc_dexp().
1410 * @param dlc precalculated values, determine range of factors
1411 * @param input point on the curve to factor
1412 * @return INT_MAX if dlog failed, otherwise the factor
1415 GNUNET_CRYPTO_ecc_dlog (struct GNUNET_CRYPTO_EccDlogContext *edc,
1416 gcry_mpi_point_t input);
1420 * Multiply the generator g of the elliptic curve by @a val
1421 * to obtain the point on the curve representing @a val.
1422 * Afterwards, point addition will correspond to integer
1423 * addition. #GNUNET_CRYPTO_ecc_dlog() can be used to
1424 * convert a point back to an integer (as long as the
1425 * integer is smaller than the MAX of the @a edc context).
1427 * @param edc calculation context for ECC operations
1428 * @param val value to encode into a point
1429 * @return representation of the value as an ECC point,
1430 * must be freed using #GNUNET_CRYPTO_ecc_free()
1433 GNUNET_CRYPTO_ecc_dexp (struct GNUNET_CRYPTO_EccDlogContext *edc, int val);
1437 * Multiply the generator g of the elliptic curve by @a val
1438 * to obtain the point on the curve representing @a val.
1440 * @param edc calculation context for ECC operations
1441 * @param val (positive) value to encode into a point
1442 * @return representation of the value as an ECC point,
1443 * must be freed using #GNUNET_CRYPTO_ecc_free()
1446 GNUNET_CRYPTO_ecc_dexp_mpi (struct GNUNET_CRYPTO_EccDlogContext *edc,
1451 * Multiply the point @a p on the elliptic curve by @a val.
1453 * @param edc calculation context for ECC operations
1454 * @param p point to multiply
1455 * @param val (positive) value to encode into a point
1456 * @return representation of the value as an ECC point,
1457 * must be freed using #GNUNET_CRYPTO_ecc_free()
1460 GNUNET_CRYPTO_ecc_pmul_mpi (struct GNUNET_CRYPTO_EccDlogContext *edc,
1466 * Convert point value to binary representation.
1468 * @param edc calculation context for ECC operations
1469 * @param point computational point representation
1470 * @param[out] bin binary point representation
1473 GNUNET_CRYPTO_ecc_point_to_bin (struct GNUNET_CRYPTO_EccDlogContext *edc,
1474 gcry_mpi_point_t point,
1475 struct GNUNET_CRYPTO_EccPoint *bin);
1479 * Convert binary representation of a point to computational representation.
1481 * @param edc calculation context for ECC operations
1482 * @param bin binary point representation
1483 * @return computational representation
1486 GNUNET_CRYPTO_ecc_bin_to_point (struct GNUNET_CRYPTO_EccDlogContext *edc,
1487 const struct GNUNET_CRYPTO_EccPoint *bin);
1491 * Add two points on the elliptic curve.
1493 * @param edc calculation context for ECC operations
1494 * @param a some value
1495 * @param b some value
1496 * @return @a a + @a b, must be freed using #GNUNET_CRYPTO_ecc_free()
1499 GNUNET_CRYPTO_ecc_add (struct GNUNET_CRYPTO_EccDlogContext *edc,
1501 gcry_mpi_point_t b);
1505 * Obtain a random point on the curve and its
1506 * additive inverse. Both returned values
1507 * must be freed using #GNUNET_CRYPTO_ecc_free().
1509 * @param edc calculation context for ECC operations
1510 * @param[out] r set to a random point on the curve
1511 * @param[out] r_inv set to the additive inverse of @a r
1514 GNUNET_CRYPTO_ecc_rnd (struct GNUNET_CRYPTO_EccDlogContext *edc,
1515 gcry_mpi_point_t *r,
1516 gcry_mpi_point_t *r_inv);
1520 * Obtain a random scalar for point multiplication on the curve and
1521 * its multiplicative inverse.
1523 * @param edc calculation context for ECC operations
1524 * @param[out] r set to a random scalar on the curve
1525 * @param[out] r_inv set to the multiplicative inverse of @a r
1528 GNUNET_CRYPTO_ecc_rnd_mpi (struct GNUNET_CRYPTO_EccDlogContext *edc,
1534 * Generate a random value mod n.
1536 * @param edc ECC context
1537 * @return random value mod n.
1540 GNUNET_CRYPTO_ecc_random_mod_n (struct GNUNET_CRYPTO_EccDlogContext *edc);
1544 * Free a point value returned by the API.
1546 * @param p point to free
1549 GNUNET_CRYPTO_ecc_free (gcry_mpi_point_t p);
1553 * Release precalculated values.
1555 * @param dlc dlog context
1558 GNUNET_CRYPTO_ecc_dlog_release (struct GNUNET_CRYPTO_EccDlogContext *dlc);
1563 * Derive key material from a public and a private ECC key.
1565 * @param priv private key to use for the ECDH (x)
1566 * @param pub public key to use for the ECDH (yG)
1567 * @param key_material where to write the key material (xyG)
1568 * @return #GNUNET_SYSERR on error, #GNUNET_OK on success
1571 GNUNET_CRYPTO_ecc_ecdh (const struct GNUNET_CRYPTO_EcdhePrivateKey *priv,
1572 const struct GNUNET_CRYPTO_EcdhePublicKey *pub,
1573 struct GNUNET_HashCode *key_material);
1578 * Derive key material from a ECDH public key and a private EdDSA key.
1579 * Dual to #GNUNET_CRRYPTO_ecdh_eddsa.
1581 * @param priv private key from EdDSA to use for the ECDH (x)
1582 * @param pub public key to use for the ECDH (yG)
1583 * @param key_material where to write the key material H(h(x)yG)
1584 * @return #GNUNET_SYSERR on error, #GNUNET_OK on success
1587 GNUNET_CRYPTO_eddsa_ecdh (const struct GNUNET_CRYPTO_EddsaPrivateKey *priv,
1588 const struct GNUNET_CRYPTO_EcdhePublicKey *pub,
1589 struct GNUNET_HashCode *key_material);
1593 * Derive key material from a ECDH public key and a private ECDSA key.
1594 * Dual to #GNUNET_CRRYPTO_ecdh_ecdsa.
1596 * @param priv private key from ECDSA to use for the ECDH (x)
1597 * @param pub public key to use for the ECDH (yG)
1598 * @param key_material where to write the key material H(h(x)yG)
1599 * @return #GNUNET_SYSERR on error, #GNUNET_OK on success
1602 GNUNET_CRYPTO_ecdsa_ecdh (const struct GNUNET_CRYPTO_EcdsaPrivateKey *priv,
1603 const struct GNUNET_CRYPTO_EcdhePublicKey *pub,
1604 struct GNUNET_HashCode *key_material);
1609 * Derive key material from a EdDSA public key and a private ECDH key.
1610 * Dual to #GNUNET_CRRYPTO_eddsa_ecdh.
1612 * @param priv private key to use for the ECDH (y)
1613 * @param pub public key from EdDSA to use for the ECDH (X=h(x)G)
1614 * @param key_material where to write the key material H(yX)=H(h(x)yG)
1615 * @return #GNUNET_SYSERR on error, #GNUNET_OK on success
1618 GNUNET_CRYPTO_ecdh_eddsa (const struct GNUNET_CRYPTO_EcdhePrivateKey *priv,
1619 const struct GNUNET_CRYPTO_EddsaPublicKey *pub,
1620 struct GNUNET_HashCode *key_material);
1624 * Derive key material from a EcDSA public key and a private ECDH key.
1625 * Dual to #GNUNET_CRRYPTO_ecdsa_ecdh.
1627 * @param priv private key to use for the ECDH (y)
1628 * @param pub public key from ECDSA to use for the ECDH (X=h(x)G)
1629 * @param key_material where to write the key material H(yX)=H(h(x)yG)
1630 * @return #GNUNET_SYSERR on error, #GNUNET_OK on success
1633 GNUNET_CRYPTO_ecdh_ecdsa (const struct GNUNET_CRYPTO_EcdhePrivateKey *priv,
1634 const struct GNUNET_CRYPTO_EcdsaPublicKey *pub,
1635 struct GNUNET_HashCode *key_material);
1640 * EdDSA sign a given block.
1642 * @param priv private key to use for the signing
1643 * @param purpose what to sign (size, purpose)
1644 * @param sig where to write the signature
1645 * @return #GNUNET_SYSERR on error, #GNUNET_OK on success
1648 GNUNET_CRYPTO_eddsa_sign (
1649 const struct GNUNET_CRYPTO_EddsaPrivateKey *priv,
1650 const struct GNUNET_CRYPTO_EccSignaturePurpose *purpose,
1651 struct GNUNET_CRYPTO_EddsaSignature *sig);
1656 * ECDSA Sign a given block.
1658 * @param priv private key to use for the signing
1659 * @param purpose what to sign (size, purpose)
1660 * @param sig where to write the signature
1661 * @return #GNUNET_SYSERR on error, #GNUNET_OK on success
1664 GNUNET_CRYPTO_ecdsa_sign (
1665 const struct GNUNET_CRYPTO_EcdsaPrivateKey *priv,
1666 const struct GNUNET_CRYPTO_EccSignaturePurpose *purpose,
1667 struct GNUNET_CRYPTO_EcdsaSignature *sig);
1671 * Verify EdDSA signature.
1673 * @param purpose what is the purpose that the signature should have?
1674 * @param validate block to validate (size, purpose, data)
1675 * @param sig signature that is being validated
1676 * @param pub public key of the signer
1677 * @returns #GNUNET_OK if ok, #GNUNET_SYSERR if invalid
1680 GNUNET_CRYPTO_eddsa_verify (
1682 const struct GNUNET_CRYPTO_EccSignaturePurpose *validate,
1683 const struct GNUNET_CRYPTO_EddsaSignature *sig,
1684 const struct GNUNET_CRYPTO_EddsaPublicKey *pub);
1689 * Verify ECDSA signature.
1691 * @param purpose what is the purpose that the signature should have?
1692 * @param validate block to validate (size, purpose, data)
1693 * @param sig signature that is being validated
1694 * @param pub public key of the signer
1695 * @returns #GNUNET_OK if ok, #GNUNET_SYSERR if invalid
1698 GNUNET_CRYPTO_ecdsa_verify (
1700 const struct GNUNET_CRYPTO_EccSignaturePurpose *validate,
1701 const struct GNUNET_CRYPTO_EcdsaSignature *sig,
1702 const struct GNUNET_CRYPTO_EcdsaPublicKey *pub);
1707 * Derive a private key from a given private key and a label.
1708 * Essentially calculates a private key 'h = H(l,P) * d mod n'
1709 * where n is the size of the ECC group and P is the public
1710 * key associated with the private key 'd'.
1712 * @param priv original private key
1713 * @param label label to use for key deriviation
1714 * @param context additional context to use for HKDF of 'h';
1715 * typically the name of the subsystem/application
1716 * @return derived private key
1718 struct GNUNET_CRYPTO_EcdsaPrivateKey *
1719 GNUNET_CRYPTO_ecdsa_private_key_derive (
1720 const struct GNUNET_CRYPTO_EcdsaPrivateKey *priv,
1722 const char *context);
1727 * Derive a public key from a given public key and a label.
1728 * Essentially calculates a public key 'V = H(l,P) * P'.
1730 * @param pub original public key
1731 * @param label label to use for key deriviation
1732 * @param context additional context to use for HKDF of 'h'.
1733 * typically the name of the subsystem/application
1734 * @param result where to write the derived public key
1737 GNUNET_CRYPTO_ecdsa_public_key_derive (
1738 const struct GNUNET_CRYPTO_EcdsaPublicKey *pub,
1740 const char *context,
1741 struct GNUNET_CRYPTO_EcdsaPublicKey *result);
1745 * Output the given MPI value to the given buffer in network
1746 * byte order. The MPI @a val may not be negative.
1748 * @param buf where to output to
1749 * @param size number of bytes in @a buf
1750 * @param val value to write to @a buf
1753 GNUNET_CRYPTO_mpi_print_unsigned (void *buf, size_t size, gcry_mpi_t val);
1757 * Convert data buffer into MPI value.
1758 * The buffer is interpreted as network
1759 * byte order, unsigned integer.
1761 * @param result where to store MPI value (allocated)
1762 * @param data raw data (GCRYMPI_FMT_USG)
1763 * @param size number of bytes in @a data
1766 GNUNET_CRYPTO_mpi_scan_unsigned (gcry_mpi_t *result,
1772 * Create a freshly generated paillier public key.
1774 * @param[out] public_key Where to store the public key?
1775 * @param[out] private_key Where to store the private key?
1778 GNUNET_CRYPTO_paillier_create (
1779 struct GNUNET_CRYPTO_PaillierPublicKey *public_key,
1780 struct GNUNET_CRYPTO_PaillierPrivateKey *private_key);
1784 * Encrypt a plaintext with a paillier public key.
1786 * @param public_key Public key to use.
1787 * @param m Plaintext to encrypt.
1788 * @param desired_ops How many homomorphic ops the caller intends to use
1789 * @param[out] ciphertext Encrytion of @a plaintext with @a public_key.
1790 * @return guaranteed number of supported homomorphic operations >= 1,
1791 * or desired_ops, in case that is lower,
1792 * or -1 if less than one homomorphic operation is possible
1795 GNUNET_CRYPTO_paillier_encrypt (
1796 const struct GNUNET_CRYPTO_PaillierPublicKey *public_key,
1799 struct GNUNET_CRYPTO_PaillierCiphertext *ciphertext);
1803 * Decrypt a paillier ciphertext with a private key.
1805 * @param private_key Private key to use for decryption.
1806 * @param public_key Public key to use for decryption.
1807 * @param ciphertext Ciphertext to decrypt.
1808 * @param[out] m Decryption of @a ciphertext with @private_key.
1811 GNUNET_CRYPTO_paillier_decrypt (
1812 const struct GNUNET_CRYPTO_PaillierPrivateKey *private_key,
1813 const struct GNUNET_CRYPTO_PaillierPublicKey *public_key,
1814 const struct GNUNET_CRYPTO_PaillierCiphertext *ciphertext,
1819 * Compute a ciphertext that represents the sum of the plaintext in @a x1 and @a x2
1821 * Note that this operation can only be done a finite number of times
1822 * before an overflow occurs.
1824 * @param public_key Public key to use for encryption.
1825 * @param c1 Paillier cipher text.
1826 * @param c2 Paillier cipher text.
1827 * @param[out] result Result of the homomorphic operation.
1828 * @return #GNUNET_OK if the result could be computed,
1829 * #GNUNET_SYSERR if no more homomorphic operations are remaining.
1832 GNUNET_CRYPTO_paillier_hom_add (
1833 const struct GNUNET_CRYPTO_PaillierPublicKey *public_key,
1834 const struct GNUNET_CRYPTO_PaillierCiphertext *c1,
1835 const struct GNUNET_CRYPTO_PaillierCiphertext *c2,
1836 struct GNUNET_CRYPTO_PaillierCiphertext *result);
1840 * Get the number of remaining supported homomorphic operations.
1842 * @param c Paillier cipher text.
1843 * @return the number of remaining homomorphic operations
1846 GNUNET_CRYPTO_paillier_hom_get_remaining (
1847 const struct GNUNET_CRYPTO_PaillierCiphertext *c);
1850 /* ********* Chaum-style RSA-based blind signatures ******************* */
1854 * The private information of an RSA key pair.
1856 struct GNUNET_CRYPTO_RsaPrivateKey;
1859 * The public information of an RSA key pair.
1861 struct GNUNET_CRYPTO_RsaPublicKey;
1864 * Constant-size pre-secret for blinding key generation.
1866 struct GNUNET_CRYPTO_RsaBlindingKeySecret
1869 * Bits used to generate the blinding key. 256 bits
1870 * of entropy is enough.
1872 uint32_t pre_secret[8] GNUNET_PACKED;
1876 * @brief an RSA signature
1878 struct GNUNET_CRYPTO_RsaSignature;
1882 * Create a new private key. Caller must free return value.
1884 * @param len length of the key in bits (i.e. 2048)
1885 * @return fresh private key
1887 struct GNUNET_CRYPTO_RsaPrivateKey *
1888 GNUNET_CRYPTO_rsa_private_key_create (unsigned int len);
1892 * Free memory occupied by the private key.
1894 * @param key pointer to the memory to free
1897 GNUNET_CRYPTO_rsa_private_key_free (struct GNUNET_CRYPTO_RsaPrivateKey *key);
1901 * Encode the private key in a format suitable for
1902 * storing it into a file.
1904 * @param key the private key
1905 * @param[out] buffer set to a buffer with the encoded key
1906 * @return size of memory allocatedin @a buffer
1909 GNUNET_CRYPTO_rsa_private_key_encode (
1910 const struct GNUNET_CRYPTO_RsaPrivateKey *key,
1915 * Decode the private key from the data-format back
1916 * to the "normal", internal format.
1918 * @param buf the buffer where the private key data is stored
1919 * @param len the length of the data in @a buf
1920 * @return NULL on error
1922 struct GNUNET_CRYPTO_RsaPrivateKey *
1923 GNUNET_CRYPTO_rsa_private_key_decode (const char *buf, size_t len);
1927 * Duplicate the given private key
1929 * @param key the private key to duplicate
1930 * @return the duplicate key; NULL upon error
1932 struct GNUNET_CRYPTO_RsaPrivateKey *
1933 GNUNET_CRYPTO_rsa_private_key_dup (
1934 const struct GNUNET_CRYPTO_RsaPrivateKey *key);
1938 * Extract the public key of the given private key.
1940 * @param priv the private key
1941 * @retur NULL on error, otherwise the public key
1943 struct GNUNET_CRYPTO_RsaPublicKey *
1944 GNUNET_CRYPTO_rsa_private_key_get_public (
1945 const struct GNUNET_CRYPTO_RsaPrivateKey *priv);
1949 * Compute hash over the public key.
1951 * @param key public key to hash
1952 * @param hc where to store the hash code
1955 GNUNET_CRYPTO_rsa_public_key_hash (const struct GNUNET_CRYPTO_RsaPublicKey *key,
1956 struct GNUNET_HashCode *hc);
1960 * Obtain the length of the RSA key in bits.
1962 * @param key the public key to introspect
1963 * @return length of the key in bits
1966 GNUNET_CRYPTO_rsa_public_key_len (const struct GNUNET_CRYPTO_RsaPublicKey *key);
1970 * Free memory occupied by the public key.
1972 * @param key pointer to the memory to free
1975 GNUNET_CRYPTO_rsa_public_key_free (struct GNUNET_CRYPTO_RsaPublicKey *key);
1979 * Encode the public key in a format suitable for
1980 * storing it into a file.
1982 * @param key the private key
1983 * @param[out] buffer set to a buffer with the encoded key
1984 * @return size of memory allocated in @a buffer
1987 GNUNET_CRYPTO_rsa_public_key_encode (
1988 const struct GNUNET_CRYPTO_RsaPublicKey *key,
1993 * Decode the public key from the data-format back
1994 * to the "normal", internal format.
1996 * @param buf the buffer where the public key data is stored
1997 * @param len the length of the data in @a buf
1998 * @return NULL on error
2000 struct GNUNET_CRYPTO_RsaPublicKey *
2001 GNUNET_CRYPTO_rsa_public_key_decode (const char *buf, size_t len);
2005 * Duplicate the given public key
2007 * @param key the public key to duplicate
2008 * @return the duplicate key; NULL upon error
2010 struct GNUNET_CRYPTO_RsaPublicKey *
2011 GNUNET_CRYPTO_rsa_public_key_dup (const struct GNUNET_CRYPTO_RsaPublicKey *key);
2015 * Compare the values of two signatures.
2017 * @param s1 one signature
2018 * @param s2 the other signature
2019 * @return 0 if the two are equal
2022 GNUNET_CRYPTO_rsa_signature_cmp (struct GNUNET_CRYPTO_RsaSignature *s1,
2023 struct GNUNET_CRYPTO_RsaSignature *s2);
2026 * Compare the values of two private keys.
2028 * @param p1 one private key
2029 * @param p2 the other private key
2030 * @return 0 if the two are equal
2033 GNUNET_CRYPTO_rsa_private_key_cmp (struct GNUNET_CRYPTO_RsaPrivateKey *p1,
2034 struct GNUNET_CRYPTO_RsaPrivateKey *p2);
2038 * Compare the values of two public keys.
2040 * @param p1 one public key
2041 * @param p2 the other public key
2042 * @return 0 if the two are equal
2045 GNUNET_CRYPTO_rsa_public_key_cmp (struct GNUNET_CRYPTO_RsaPublicKey *p1,
2046 struct GNUNET_CRYPTO_RsaPublicKey *p2);
2050 * Blinds the given message with the given blinding key
2052 * @param hash hash of the message to sign
2053 * @param bkey the blinding key
2054 * @param pkey the public key of the signer
2055 * @param[out] buf set to a buffer with the blinded message to be signed
2056 * @param[out] buf_size number of bytes stored in @a buf
2057 * @return #GNUNET_YES if successful, #GNUNET_NO if RSA key is malicious
2060 GNUNET_CRYPTO_rsa_blind (const struct GNUNET_HashCode *hash,
2061 const struct GNUNET_CRYPTO_RsaBlindingKeySecret *bks,
2062 struct GNUNET_CRYPTO_RsaPublicKey *pkey,
2068 * Sign a blinded value, which must be a full domain hash of a message.
2070 * @param key private key to use for the signing
2071 * @param msg the (blinded) message to sign
2072 * @param msg_len number of bytes in @a msg to sign
2073 * @return NULL on error, signature on success
2075 struct GNUNET_CRYPTO_RsaSignature *
2076 GNUNET_CRYPTO_rsa_sign_blinded (const struct GNUNET_CRYPTO_RsaPrivateKey *key,
2082 * Create and sign a full domain hash of a message.
2084 * @param key private key to use for the signing
2085 * @param hash the hash of the message to sign
2086 * @return NULL on error, including a malicious RSA key, signature on success
2088 struct GNUNET_CRYPTO_RsaSignature *
2089 GNUNET_CRYPTO_rsa_sign_fdh (const struct GNUNET_CRYPTO_RsaPrivateKey *key,
2090 const struct GNUNET_HashCode *hash);
2094 * Free memory occupied by signature.
2096 * @param sig memory to free
2099 GNUNET_CRYPTO_rsa_signature_free (struct GNUNET_CRYPTO_RsaSignature *sig);
2103 * Encode the given signature in a format suitable for storing it into a file.
2105 * @param sig the signature
2106 * @param[out] buffer set to a buffer with the encoded key
2107 * @return size of memory allocated in @a buffer
2110 GNUNET_CRYPTO_rsa_signature_encode (
2111 const struct GNUNET_CRYPTO_RsaSignature *sig,
2116 * Decode the signature from the data-format back to the "normal", internal
2119 * @param buf the buffer where the public key data is stored
2120 * @param len the length of the data in @a buf
2121 * @return NULL on error
2123 struct GNUNET_CRYPTO_RsaSignature *
2124 GNUNET_CRYPTO_rsa_signature_decode (const char *buf, size_t len);
2128 * Duplicate the given rsa signature
2130 * @param sig the signature to duplicate
2131 * @return the duplicate key; NULL upon error
2133 struct GNUNET_CRYPTO_RsaSignature *
2134 GNUNET_CRYPTO_rsa_signature_dup (const struct GNUNET_CRYPTO_RsaSignature *sig);
2138 * Unblind a blind-signed signature. The signature should have been generated
2139 * with #GNUNET_CRYPTO_rsa_sign() using a hash that was blinded with
2140 * #GNUNET_CRYPTO_rsa_blind().
2142 * @param sig the signature made on the blinded signature purpose
2143 * @param bks the blinding key secret used to blind the signature purpose
2144 * @param pkey the public key of the signer
2145 * @return unblinded signature on success, NULL if RSA key is bad or malicious.
2147 struct GNUNET_CRYPTO_RsaSignature *
2148 GNUNET_CRYPTO_rsa_unblind (const struct GNUNET_CRYPTO_RsaSignature *sig,
2149 const struct GNUNET_CRYPTO_RsaBlindingKeySecret *bks,
2150 struct GNUNET_CRYPTO_RsaPublicKey *pkey);
2154 * Verify whether the given hash corresponds to the given signature and the
2155 * signature is valid with respect to the given public key.
2157 * @param hash the message to verify to match the @a sig
2158 * @param sig signature that is being validated
2159 * @param public_key public key of the signer
2160 * @returns #GNUNET_YES if ok, #GNUNET_NO if RSA key is malicious, #GNUNET_SYSERR if signature
2163 GNUNET_CRYPTO_rsa_verify (const struct GNUNET_HashCode *hash,
2164 const struct GNUNET_CRYPTO_RsaSignature *sig,
2165 const struct GNUNET_CRYPTO_RsaPublicKey *public_key);
2168 #if 0 /* keep Emacsens' auto-indent happy */
2176 /* ifndef GNUNET_CRYPTO_LIB_H */
2178 /* end of gnunet_crypto_lib.h */