/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) * All rights reserved. * * This package is an SSL implementation written * by Eric Young (eay@cryptsoft.com). * The implementation was written so as to conform with Netscapes SSL. * * This library is free for commercial and non-commercial use as long as * the following conditions are aheared to. The following conditions * apply to all code found in this distribution, be it the RC4, RSA, * lhash, DES, etc., code; not just the SSL code. The SSL documentation * included with this distribution is covered by the same copyright terms * except that the holder is Tim Hudson (tjh@cryptsoft.com). * * Copyright remains Eric Young's, and as such any Copyright notices in * the code are not to be removed. * If this package is used in a product, Eric Young should be given attribution * as the author of the parts of the library used. * This can be in the form of a textual message at program startup or * in documentation (online or textual) provided with the package. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * "This product includes cryptographic software written by * Eric Young (eay@cryptsoft.com)" * The word 'cryptographic' can be left out if the rouines from the library * being used are not cryptographic related :-). * 4. If you include any Windows specific code (or a derivative thereof) from * the apps directory (application code) you must include an acknowledgement: * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" * * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * The licence and distribution terms for any publically available version or * derivative of this code cannot be changed. i.e. this code cannot simply be * copied and put under another distribution licence * [including the GNU Public Licence.] * * The DSS routines are based on patches supplied by * Steven Schoch . */ #ifndef OPENSSL_HEADER_DSA_H #define OPENSSL_HEADER_DSA_H #include #include #include #include #if defined(__cplusplus) extern "C" { #endif /* DSA contains functions for signing and verifing with the Digital Signature * Algorithm. */ /* Allocation and destruction. */ /* DSA_new returns a new, empty DSA object or NULL on error. */ OPENSSL_EXPORT DSA *DSA_new(void); /* DSA_free decrements the reference count of |dsa| and frees it if the * reference count drops to zero. */ OPENSSL_EXPORT void DSA_free(DSA *dsa); /* DSA_up_ref increments the reference count of |dsa|. */ OPENSSL_EXPORT int DSA_up_ref(DSA *dsa); /* Parameter generation. */ /* DSA_generate_parameters_ex generates a set of DSA parameters by following * the procedure given in FIPS 186-4, appendix A. * (http://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.186-4.pdf) * * The larger prime will have a length of |bits| (e.g. 2048). The |seed| value * allows others to generate and verify the same parameters and should be * random input which is kept for reference. If |out_counter| or |out_h| are * not NULL then the counter and h value used in the generation are written to * them. * * The |cb| argument is passed to |BN_generate_prime_ex| and is thus called * during the generation process in order to indicate progress. See the * comments for that function for details. In addition to the calls made by * |BN_generate_prime_ex|, |DSA_generate_parameters_ex| will call it with * |event| equal to 2 and 3 at different stages of the process. * * It returns one on success and zero otherwise. */ OPENSSL_EXPORT int DSA_generate_parameters_ex(DSA *dsa, unsigned bits, const uint8_t *seed, size_t seed_len, int *out_counter, unsigned long *out_h, BN_GENCB *cb); /* DSAparams_dup returns a freshly allocated |DSA| that contains a copy of the * parameters from |dsa|. It returns NULL on error. */ OPENSSL_EXPORT DSA *DSAparams_dup(const DSA *dsa); /* Key generation. */ /* DSA_generate_key generates a public/private key pair in |dsa|, which must * already have parameters setup. It returns one on success and zero on * error. */ OPENSSL_EXPORT int DSA_generate_key(DSA *dsa); /* Signatures. */ /* DSA_SIG_st (aka |DSA_SIG|) contains a DSA signature as a pair of integers. */ struct DSA_SIG_st { BIGNUM *r, *s; }; /* DSA_SIG_new returns a freshly allocated, DIG_SIG structure or NULL on error. * Both |r| and |s| in the signature will be NULL. */ OPENSSL_EXPORT DSA_SIG *DSA_SIG_new(void); /* DSA_SIG_free frees the contents of |sig| and then frees |sig| itself. */ OPENSSL_EXPORT void DSA_SIG_free(DSA_SIG *sig); /* DSA_do_sign returns a signature of the hash in |digest| by the key in |dsa| * and returns an allocated, DSA_SIG structure, or NULL on error. */ OPENSSL_EXPORT DSA_SIG *DSA_do_sign(const uint8_t *digest, size_t digest_len, DSA *dsa); /* DSA_do_verify verifies that |sig| is a valid signature, by the public key in * |dsa|, of the hash in |digest|. It returns one if so, zero if invalid and -1 * on error. * * WARNING: do not use. This function returns -1 for error, 0 for invalid and 1 * for valid. However, this is dangerously different to the usual OpenSSL * convention and could be a disaster if a user did |if (DSA_do_verify(...))|. * Because of this, |DSA_check_signature| is a safer version of this. * * TODO(fork): deprecate. */ OPENSSL_EXPORT int DSA_do_verify(const uint8_t *digest, size_t digest_len, DSA_SIG *sig, const DSA *dsa); /* DSA_do_check_signature sets |*out_valid| to zero. Then it verifies that |sig| * is a valid signature, by the public key in |dsa| of the hash in |digest| * and, if so, it sets |*out_valid| to one. * * It returns one if it was able to verify the signature as valid or invalid, * and zero on error. */ OPENSSL_EXPORT int DSA_do_check_signature(int *out_valid, const uint8_t *digest, size_t digest_len, DSA_SIG *sig, const DSA *dsa); /* ASN.1 signatures. * * These functions also perform DSA signature operations, but deal with ASN.1 * encoded signatures as opposed to raw |BIGNUM|s. If you don't know what * encoding a DSA signature is in, it's probably ASN.1. */ /* DSA_sign signs |digest| with the key in |dsa| and writes the resulting * signature, in ASN.1 form, to |out_sig| and the length of the signature to * |*out_siglen|. There must be, at least, |DSA_size(dsa)| bytes of space in * |out_sig|. It returns one on success and zero otherwise. * * (The |type| argument is ignored.) */ OPENSSL_EXPORT int DSA_sign(int type, const uint8_t *digest, size_t digest_len, uint8_t *out_sig, unsigned int *out_siglen, DSA *dsa); /* DSA_verify verifies that |sig| is a valid, ASN.1 signature, by the public * key in |dsa|, of the hash in |digest|. It returns one if so, zero if invalid * and -1 on error. * * (The |type| argument is ignored.) * * WARNING: do not use. This function returns -1 for error, 0 for invalid and 1 * for valid. However, this is dangerously different to the usual OpenSSL * convention and could be a disaster if a user did |if (DSA_do_verify(...))|. * Because of this, |DSA_check_signature| is a safer version of this. * * TODO(fork): deprecate. */ OPENSSL_EXPORT int DSA_verify(int type, const uint8_t *digest, size_t digest_len, const uint8_t *sig, size_t sig_len, const DSA *dsa); /* DSA_check_signature sets |*out_valid| to zero. Then it verifies that |sig| * is a valid, ASN.1 signature, by the public key in |dsa|, of the hash in * |digest|. If so, it sets |*out_valid| to one. * * It returns one if it was able to verify the signature as valid or invalid, * and zero on error. */ OPENSSL_EXPORT int DSA_check_signature(int *out_valid, const uint8_t *digest, size_t digest_len, const uint8_t *sig, size_t sig_len, const DSA *dsa); /* DSA_size returns the size, in bytes, of an ASN.1 encoded, DSA signature * generated by |dsa|. Parameters must already have been setup in |dsa|. */ OPENSSL_EXPORT int DSA_size(const DSA *dsa); /* ASN.1 encoding. */ /* DSA_SIG_parse parses a DER-encoded DSA-Sig-Value structure from |cbs| and * advances |cbs|. It returns a newly-allocated |DSA_SIG| or NULL on error. */ OPENSSL_EXPORT DSA_SIG *DSA_SIG_parse(CBS *cbs); /* DSA_SIG_marshal marshals |sig| as a DER-encoded DSA-Sig-Value and appends the * result to |cbb|. It returns one on success and zero on error. */ OPENSSL_EXPORT int DSA_SIG_marshal(CBB *cbb, const DSA_SIG *sig); /* DSA_parse_public_key parses a DER-encoded DSA public key from |cbs| and * advances |cbs|. It returns a newly-allocated |DSA| or NULL on error. */ OPENSSL_EXPORT DSA *DSA_parse_public_key(CBS *cbs); /* DSA_marshal_public_key marshals |dsa| as a DER-encoded DSA public key and * appends the result to |cbb|. It returns one on success and zero on * failure. */ OPENSSL_EXPORT int DSA_marshal_public_key(CBB *cbb, const DSA *dsa); /* DSA_parse_private_key parses a DER-encoded DSA private key from |cbs| and * advances |cbs|. It returns a newly-allocated |DSA| or NULL on error. */ OPENSSL_EXPORT DSA *DSA_parse_private_key(CBS *cbs); /* DSA_marshal_private_key marshals |dsa| as a DER-encoded DSA private key and * appends the result to |cbb|. It returns one on success and zero on * failure. */ OPENSSL_EXPORT int DSA_marshal_private_key(CBB *cbb, const DSA *dsa); /* DSA_parse_parameters parses a DER-encoded Dss-Parms structure (RFC 3279) * from |cbs| and advances |cbs|. It returns a newly-allocated |DSA| or NULL on * error. */ OPENSSL_EXPORT DSA *DSA_parse_parameters(CBS *cbs); /* DSA_marshal_parameters marshals |dsa| as a DER-encoded Dss-Parms structure * (RFC 3447) and appends the result to |cbb|. It returns one on success and * zero on failure. */ OPENSSL_EXPORT int DSA_marshal_parameters(CBB *cbb, const DSA *dsa); /* Precomputation. */ /* DSA_sign_setup precomputes the message independent part of the DSA signature * and writes them to |*out_kinv| and |*out_r|. Returns one on success, zero on * error. * * TODO(fork): decide what to do with this. Since making DSA* opaque there's no * way for the user to install them. Also, it forces the DSA* not to be const * when passing to the signing function. */ OPENSSL_EXPORT int DSA_sign_setup(const DSA *dsa, BN_CTX *ctx, BIGNUM **out_kinv, BIGNUM **out_r); /* Conversion. */ /* DSA_dup_DH returns a |DH| constructed from the parameters of |dsa|. This is * sometimes needed when Diffie-Hellman parameters are stored in the form of * DSA parameters. It returns an allocated |DH| on success or NULL on error. */ OPENSSL_EXPORT DH *DSA_dup_DH(const DSA *dsa); /* ex_data functions. * * See |ex_data.h| for details. */ OPENSSL_EXPORT int DSA_get_ex_new_index(long argl, void *argp, CRYPTO_EX_unused *unused, CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func); OPENSSL_EXPORT int DSA_set_ex_data(DSA *d, int idx, void *arg); OPENSSL_EXPORT void *DSA_get_ex_data(const DSA *d, int idx); /* Deprecated functions. */ /* d2i_DSA_SIG parses an ASN.1, DER-encoded, DSA signature from |len| bytes at * |*inp|. If |out_sig| is not NULL then, on exit, a pointer to the result is * in |*out_sig|. Note that, even if |*out_sig| is already non-NULL on entry, it * will not be written to. Rather, a fresh |DSA_SIG| is allocated and the * previous one is freed. On successful exit, |*inp| is advanced past the DER * structure. It returns the result or NULL on error. * * Use |DSA_SIG_parse| instead. */ OPENSSL_EXPORT DSA_SIG *d2i_DSA_SIG(DSA_SIG **out_sig, const uint8_t **inp, long len); /* i2d_DSA_SIG marshals |in| to an ASN.1, DER structure. If |outp| is not NULL * then the result is written to |*outp| and |*outp| is advanced just past the * output. It returns the number of bytes in the result, whether written or not, * or a negative value on error. * * Use |DSA_SIG_marshal| instead. */ OPENSSL_EXPORT int i2d_DSA_SIG(const DSA_SIG *in, uint8_t **outp); /* d2i_DSAPublicKey parses an ASN.1, DER-encoded, DSA public key from |len| * bytes at |*inp|. If |out| is not NULL then, on exit, a pointer to the result * is in |*out|. Note that, even if |*ou| is already non-NULL on entry, it will * not be written to. Rather, a fresh |DSA| is allocated and the previous one is * freed. On successful exit, |*inp| is advanced past the DER structure. It * returns the result or NULL on error. * * Use |DSA_parse_public_key| instead. */ OPENSSL_EXPORT DSA *d2i_DSAPublicKey(DSA **out, const uint8_t **inp, long len); /* i2d_DSAPublicKey marshals a public key from |in| to an ASN.1, DER structure. * If |outp| is not NULL then the result is written to |*outp| and |*outp| is * advanced just past the output. It returns the number of bytes in the result, * whether written or not, or a negative value on error. * * Use |DSA_marshal_public_key| instead. */ OPENSSL_EXPORT int i2d_DSAPublicKey(const DSA *in, uint8_t **outp); /* d2i_DSAPrivateKey parses an ASN.1, DER-encoded, DSA private key from |len| * bytes at |*inp|. If |out| is not NULL then, on exit, a pointer to the result * is in |*out|. Note that, even if |*out| is already non-NULL on entry, it will * not be written to. Rather, a fresh |DSA| is allocated and the previous one is * freed. On successful exit, |*inp| is advanced past the DER structure. It * returns the result or NULL on error. * * Use |DSA_parse_private_key| instead. */ OPENSSL_EXPORT DSA *d2i_DSAPrivateKey(DSA **out, const uint8_t **inp, long len); /* i2d_DSAPrivateKey marshals a private key from |in| to an ASN.1, DER structure. * If |outp| is not NULL then the result is written to |*outp| and |*outp| is * advanced just past the output. It returns the number of bytes in the result, * whether written or not, or a negative value on error. * * Use |DSA_marshal_private_key| instead. */ OPENSSL_EXPORT int i2d_DSAPrivateKey(const DSA *in, uint8_t **outp); /* d2i_DSAparams parses ASN.1, DER-encoded, DSA parameters from |len| bytes at * |*inp|. If |out| is not NULL then, on exit, a pointer to the result is in * |*out|. Note that, even if |*out| is already non-NULL on entry, it will not * be written to. Rather, a fresh |DSA| is allocated and the previous one is * freed. On successful exit, |*inp| is advanced past the DER structure. It * returns the result or NULL on error. * * Use |DSA_parse_parameters| instead. */ OPENSSL_EXPORT DSA *d2i_DSAparams(DSA **out, const uint8_t **inp, long len); /* i2d_DSAparams marshals DSA parameters from |in| to an ASN.1, DER structure. * If |outp| is not NULL then the result is written to |*outp| and |*outp| is * advanced just past the output. It returns the number of bytes in the result, * whether written or not, or a negative value on error. * * Use |DSA_marshal_parameters| instead. */ OPENSSL_EXPORT int i2d_DSAparams(const DSA *in, uint8_t **outp); /* DSA_generate_parameters is a deprecated version of * |DSA_generate_parameters_ex| that creates and returns a |DSA*|. Don't use * it. */ OPENSSL_EXPORT DSA *DSA_generate_parameters(int bits, unsigned char *seed, int seed_len, int *counter_ret, unsigned long *h_ret, void (*callback)(int, int, void *), void *cb_arg); struct dsa_st { long version; BIGNUM *p; BIGNUM *q; /* == 20 */ BIGNUM *g; BIGNUM *pub_key; /* y public key */ BIGNUM *priv_key; /* x private key */ BIGNUM *kinv; /* Signing pre-calc */ BIGNUM *r; /* Signing pre-calc */ int flags; /* Normally used to cache montgomery values */ CRYPTO_MUTEX method_mont_lock; BN_MONT_CTX *method_mont_p; BN_MONT_CTX *method_mont_q; CRYPTO_refcount_t references; CRYPTO_EX_DATA ex_data; }; #if defined(__cplusplus) } /* extern C */ #endif #define DSA_R_BAD_Q_VALUE 100 #define DSA_R_MISSING_PARAMETERS 101 #define DSA_R_MODULUS_TOO_LARGE 102 #define DSA_R_NEED_NEW_SETUP_VALUES 103 #define DSA_R_BAD_VERSION 104 #define DSA_R_DECODE_ERROR 105 #define DSA_R_ENCODE_ERROR 106 #endif /* OPENSSL_HEADER_DSA_H */