dh.h revision 296465 
1/* crypto/dh/dh.h */
2/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
8 *
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to.  The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 *
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
26 * 1. Redistributions of source code must retain the copyright
27 *    notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 *    notice, this list of conditions and the following disclaimer in the
30 *    documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 *    must display the following acknowledgement:
33 *    "This product includes cryptographic software written by
34 *     Eric Young (eay@cryptsoft.com)"
35 *    The word 'cryptographic' can be left out if the rouines from the library
36 *    being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 *    the apps directory (application code) you must include an acknowledgement:
39 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 *
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51 * SUCH DAMAGE.
52 *
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed.  i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
57 */
58
59#ifndef HEADER_DH_H
60# define HEADER_DH_H
61
62# include <openssl/e_os2.h>
63
64# ifdef OPENSSL_NO_DH
65#  error DH is disabled.
66# endif
67
68# ifndef OPENSSL_NO_BIO
69#  include <openssl/bio.h>
70# endif
71# include <openssl/ossl_typ.h>
72# ifndef OPENSSL_NO_DEPRECATED
73#  include <openssl/bn.h>
74# endif
75
76# ifndef OPENSSL_DH_MAX_MODULUS_BITS
77#  define OPENSSL_DH_MAX_MODULUS_BITS    10000
78# endif
79
80# define OPENSSL_DH_FIPS_MIN_MODULUS_BITS 1024
81
82# define DH_FLAG_CACHE_MONT_P     0x01
83
84/*
85 * new with 0.9.7h; the built-in DH
86 * implementation now uses constant time
87 * modular exponentiation for secret exponents
88 * by default. This flag causes the
89 * faster variable sliding window method to
90 * be used for all exponents.
91 */
92# define DH_FLAG_NO_EXP_CONSTTIME 0x02
93
94#ifdef  __cplusplus
95extern "C" {
96#endif
97
98/* Already defined in ossl_typ.h */
99/* typedef struct dh_st DH; */
100/* typedef struct dh_method DH_METHOD; */
101
102struct dh_method {
103    const char *name;
104    /* Methods here */
105    int (*generate_key) (DH *dh);
106    int (*compute_key) (unsigned char *key, const BIGNUM *pub_key, DH *dh);
107    /* Can be null */
108    int (*bn_mod_exp) (const DH *dh, BIGNUM *r, const BIGNUM *a,
109                       const BIGNUM *p, const BIGNUM *m, BN_CTX *ctx,
110                       BN_MONT_CTX *m_ctx);
111    int (*init) (DH *dh);
112    int (*finish) (DH *dh);
113    int flags;
114    char *app_data;
115    /* If this is non-NULL, it will be used to generate parameters */
116    int (*generate_params) (DH *dh, int prime_len, int generator,
117                            BN_GENCB *cb);
118};
119
120struct dh_st {
121    /*
122     * This first argument is used to pick up errors when a DH is passed
123     * instead of a EVP_PKEY
124     */
125    int pad;
126    int version;
127    BIGNUM *p;
128    BIGNUM *g;
129    long length;                /* optional */
130    BIGNUM *pub_key;            /* g^x */
131    BIGNUM *priv_key;           /* x */
132    int flags;
133    BN_MONT_CTX *method_mont_p;
134    /* Place holders if we want to do X9.42 DH */
135    BIGNUM *q;
136    BIGNUM *j;
137    unsigned char *seed;
138    int seedlen;
139    BIGNUM *counter;
140    int references;
141    CRYPTO_EX_DATA ex_data;
142    const DH_METHOD *meth;
143    ENGINE *engine;
144};
145
146# define DH_GENERATOR_2          2
147/* #define DH_GENERATOR_3       3 */
148# define DH_GENERATOR_5          5
149
150/* DH_check error codes */
151# define DH_CHECK_P_NOT_PRIME            0x01
152# define DH_CHECK_P_NOT_SAFE_PRIME       0x02
153# define DH_UNABLE_TO_CHECK_GENERATOR    0x04
154# define DH_NOT_SUITABLE_GENERATOR       0x08
155
156/* DH_check_pub_key error codes */
157# define DH_CHECK_PUBKEY_TOO_SMALL       0x01
158# define DH_CHECK_PUBKEY_TOO_LARGE       0x02
159
160/*
161 * primes p where (p-1)/2 is prime too are called "safe"; we define this for
162 * backward compatibility:
163 */
164# define DH_CHECK_P_NOT_STRONG_PRIME     DH_CHECK_P_NOT_SAFE_PRIME
165
166# define DHparams_dup(x) ASN1_dup_of_const(DH,i2d_DHparams,d2i_DHparams,x)
167# define d2i_DHparams_fp(fp,x) (DH *)ASN1_d2i_fp((char *(*)())DH_new, \
168                (char *(*)())d2i_DHparams,(fp),(unsigned char **)(x))
169# define i2d_DHparams_fp(fp,x) ASN1_i2d_fp(i2d_DHparams,(fp), \
170                (unsigned char *)(x))
171# define d2i_DHparams_bio(bp,x) ASN1_d2i_bio_of(DH,DH_new,d2i_DHparams,bp,x)
172# define i2d_DHparams_bio(bp,x) ASN1_i2d_bio_of_const(DH,i2d_DHparams,bp,x)
173
174const DH_METHOD *DH_OpenSSL(void);
175
176# ifdef OPENSSL_FIPS
177DH *FIPS_dh_new(void);
178void FIPS_dh_free(DH *dh);
179# endif
180
181void DH_set_default_method(const DH_METHOD *meth);
182const DH_METHOD *DH_get_default_method(void);
183int DH_set_method(DH *dh, const DH_METHOD *meth);
184DH *DH_new_method(ENGINE *engine);
185
186DH *DH_new(void);
187void DH_free(DH *dh);
188int DH_up_ref(DH *dh);
189int DH_size(const DH *dh);
190int DH_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
191                        CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func);
192int DH_set_ex_data(DH *d, int idx, void *arg);
193void *DH_get_ex_data(DH *d, int idx);
194
195/* Deprecated version */
196# ifndef OPENSSL_NO_DEPRECATED
197DH *DH_generate_parameters(int prime_len, int generator,
198                           void (*callback) (int, int, void *), void *cb_arg);
199# endif                         /* !defined(OPENSSL_NO_DEPRECATED) */
200
201/* New version */
202int DH_generate_parameters_ex(DH *dh, int prime_len, int generator,
203                              BN_GENCB *cb);
204
205int DH_check(const DH *dh, int *codes);
206int DH_check_pub_key(const DH *dh, const BIGNUM *pub_key, int *codes);
207int DH_generate_key(DH *dh);
208int DH_compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh);
209DH *d2i_DHparams(DH **a, const unsigned char **pp, long length);
210int i2d_DHparams(const DH *a, unsigned char **pp);
211# ifndef OPENSSL_NO_FP_API
212int DHparams_print_fp(FILE *fp, const DH *x);
213# endif
214# ifndef OPENSSL_NO_BIO
215int DHparams_print(BIO *bp, const DH *x);
216# else
217int DHparams_print(char *bp, const DH *x);
218# endif
219
220/* BEGIN ERROR CODES */
221/*
222 * The following lines are auto generated by the script mkerr.pl. Any changes
223 * made after this point may be overwritten when the script is next run.
224 */
225void ERR_load_DH_strings(void);
226
227/* Error codes for the DH functions. */
228
229/* Function codes. */
230# define DH_F_COMPUTE_KEY                                 102
231# define DH_F_DHPARAMS_PRINT                              100
232# define DH_F_DHPARAMS_PRINT_FP                           101
233# define DH_F_DH_BUILTIN_GENPARAMS                        106
234# define DH_F_DH_COMPUTE_KEY                              107
235# define DH_F_DH_GENERATE_KEY                             108
236# define DH_F_DH_GENERATE_PARAMETERS                      109
237# define DH_F_DH_NEW_METHOD                               105
238# define DH_F_GENERATE_KEY                                103
239# define DH_F_GENERATE_PARAMETERS                         104
240
241/* Reason codes. */
242# define DH_R_BAD_GENERATOR                               101
243# define DH_R_INVALID_PUBKEY                              102
244# define DH_R_KEY_SIZE_TOO_SMALL                          104
245# define DH_R_MODULUS_TOO_LARGE                           103
246# define DH_R_NO_PRIVATE_VALUE                            100
247
248#ifdef  __cplusplus
249}
250#endif
251#endif
252