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 #ifdef OPENSSL_NO_DH
63 #error DH is disabled.
64 #endif
65 
66 #ifndef OPENSSL_NO_BIO
67 #include <openssl/bio.h>
68 #endif
69 #include <openssl/bn.h>
70 #include <openssl/crypto.h>
71 #include <openssl/ossl_typ.h>
72 
73 #ifndef OPENSSL_DH_MAX_MODULUS_BITS
74 # define OPENSSL_DH_MAX_MODULUS_BITS	10000
75 #endif
76 
77 #define DH_FLAG_CACHE_MONT_P     0x01
78 #define DH_FLAG_NO_EXP_CONSTTIME 0x02 /* new with 0.9.7h; the built-in DH
79                                        * implementation now uses constant time
80                                        * modular exponentiation for secret exponents
81                                        * by default. This flag causes the
82                                        * faster variable sliding window method to
83                                        * be used for all exponents.
84                                        */
85 
86 #ifdef  __cplusplus
87 extern "C" {
88 #endif
89 
90 typedef struct dh_st DH;
91 
92 typedef struct dh_method {
93 	const char *name;
94 	/* Methods here */
95 	int (*generate_key)(DH *dh);
96 	int (*compute_key)(unsigned char *key,const BIGNUM *pub_key,DH *dh);
97 	int (*bn_mod_exp)(const DH *dh, BIGNUM *r, const BIGNUM *a,
98 				const BIGNUM *p, const BIGNUM *m, BN_CTX *ctx,
99 				BN_MONT_CTX *m_ctx); /* Can be null */
100 
101 	int (*init)(DH *dh);
102 	int (*finish)(DH *dh);
103 	int flags;
104 	char *app_data;
105 } DH_METHOD;
106 
107 struct dh_st
108 	{
109 	/* This first argument is used to pick up errors when
110 	 * a DH is passed instead of a EVP_PKEY */
111 	int pad;
112 	int version;
113 	BIGNUM *p;
114 	BIGNUM *g;
115 	int length; /* optional */
116 	BIGNUM *pub_key;	/* g^x */
117 	BIGNUM *priv_key;	/* x */
118 
119 	int flags;
120 	char *method_mont_p;
121 	/* Place holders if we want to do X9.42 DH */
122 	BIGNUM *q;
123 	BIGNUM *j;
124 	unsigned char *seed;
125 	int seedlen;
126 	BIGNUM *counter;
127 
128 	int references;
129 	CRYPTO_EX_DATA ex_data;
130 	const DH_METHOD *meth;
131 	ENGINE *engine;
132 	};
133 
134 #define DH_GENERATOR_2		2
135 /* #define DH_GENERATOR_3	3 */
136 #define DH_GENERATOR_5		5
137 
138 /* DH_check error codes */
139 #define DH_CHECK_P_NOT_PRIME		0x01
140 #define DH_CHECK_P_NOT_SAFE_PRIME	0x02
141 #define DH_UNABLE_TO_CHECK_GENERATOR	0x04
142 #define DH_NOT_SUITABLE_GENERATOR	0x08
143 
144 /* DH_check_pub_key error codes */
145 #define DH_CHECK_PUBKEY_TOO_SMALL	0x01
146 #define DH_CHECK_PUBKEY_TOO_LARGE	0x02
147 
148 /* primes p where (p-1)/2 is prime too are called "safe"; we define
149    this for backward compatibility: */
150 #define DH_CHECK_P_NOT_STRONG_PRIME	DH_CHECK_P_NOT_SAFE_PRIME
151 
152 #define DHparams_dup(x) (DH *)ASN1_dup((int (*)())i2d_DHparams, \
153 		(char *(*)())d2i_DHparams,(char *)(x))
154 #define d2i_DHparams_fp(fp,x) (DH *)ASN1_d2i_fp((char *(*)())DH_new, \
155 		(char *(*)())d2i_DHparams,(fp),(unsigned char **)(x))
156 #define i2d_DHparams_fp(fp,x) ASN1_i2d_fp(i2d_DHparams,(fp), \
157 		(unsigned char *)(x))
158 #define d2i_DHparams_bio(bp,x) (DH *)ASN1_d2i_bio((char *(*)())DH_new, \
159 		(char *(*)())d2i_DHparams,(bp),(unsigned char **)(x))
160 #ifdef  __cplusplus
161 #define i2d_DHparams_bio(bp,x) ASN1_i2d_bio((int (*)())i2d_DHparams,(bp), \
162 		(unsigned char *)(x))
163 #else
164 #define i2d_DHparams_bio(bp,x) ASN1_i2d_bio(i2d_DHparams,(bp), \
165 		(unsigned char *)(x))
166 #endif
167 
168 const DH_METHOD *DH_OpenSSL(void);
169 
170 void DH_set_default_method(const DH_METHOD *meth);
171 const DH_METHOD *DH_get_default_method(void);
172 int DH_set_method(DH *dh, const DH_METHOD *meth);
173 DH *DH_new_method(ENGINE *engine);
174 
175 DH *	DH_new(void);
176 void	DH_free(DH *dh);
177 int	DH_up_ref(DH *dh);
178 int	DH_size(const DH *dh);
179 int DH_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
180 	     CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func);
181 int DH_set_ex_data(DH *d, int idx, void *arg);
182 void *DH_get_ex_data(DH *d, int idx);
183 DH *	DH_generate_parameters(int prime_len,int generator,
184 		void (*callback)(int,int,void *),void *cb_arg);
185 int	DH_check(const DH *dh,int *codes);
186 int	DH_check_pub_key(const DH *dh,const BIGNUM *pub_key, int *codes);
187 int	DH_generate_key(DH *dh);
188 int	DH_compute_key(unsigned char *key,const BIGNUM *pub_key,DH *dh);
189 DH *	d2i_DHparams(DH **a,const unsigned char **pp, long length);
190 int	i2d_DHparams(const DH *a,unsigned char **pp);
191 #ifndef OPENSSL_NO_FP_API
192 int	DHparams_print_fp(FILE *fp, const DH *x);
193 #endif
194 #ifndef OPENSSL_NO_BIO
195 int	DHparams_print(BIO *bp, const DH *x);
196 #else
197 int	DHparams_print(char *bp, const DH *x);
198 #endif
199 
200 /* BEGIN ERROR CODES */
201 /* The following lines are auto generated by the script mkerr.pl. Any changes
202  * made after this point may be overwritten when the script is next run.
203  */
204 void ERR_load_DH_strings(void);
205 
206 /* Error codes for the DH functions. */
207 
208 /* Function codes. */
209 #define DH_F_DHPARAMS_PRINT				 100
210 #define DH_F_DHPARAMS_PRINT_FP				 101
211 #define DH_F_DH_COMPUTE_KEY				 102
212 #define DH_F_DH_GENERATE_KEY				 103
213 #define DH_F_DH_GENERATE_PARAMETERS			 104
214 #define DH_F_DH_NEW_METHOD				 105
215 
216 /* Reason codes. */
217 #define DH_R_BAD_GENERATOR				 101
218 #define DH_R_NO_PRIVATE_VALUE				 100
219 #define DH_R_INVALID_PUBKEY				 102
220 #define DH_R_MODULUS_TOO_LARGE				 103
221 
222 #ifdef  __cplusplus
223 }
224 #endif
225 #endif
226