1/* 2 * Copyright 2000-2021 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the Apache License 2.0 (the "License"). You may not use 5 * this file except in compliance with the License. You can obtain a copy 6 * in the file LICENSE in the source distribution or at 7 * https://www.openssl.org/source/license.html 8 */ 9 10/* 11 * DH low level APIs are deprecated for public use, but still ok for 12 * internal use. 13 */ 14#include "internal/deprecated.h" 15 16#include <stdio.h> 17#include "internal/cryptlib.h" 18#include <openssl/bn.h> 19#include "dh_local.h" 20#include <openssl/objects.h> 21#include <openssl/asn1t.h> 22#include "crypto/dh.h" 23 24/* Override the default free and new methods */ 25static int dh_cb(int operation, ASN1_VALUE **pval, const ASN1_ITEM *it, 26 void *exarg) 27{ 28 if (operation == ASN1_OP_NEW_PRE) { 29 *pval = (ASN1_VALUE *)DH_new(); 30 if (*pval != NULL) 31 return 2; 32 return 0; 33 } else if (operation == ASN1_OP_FREE_PRE) { 34 DH_free((DH *)*pval); 35 *pval = NULL; 36 return 2; 37 } else if (operation == ASN1_OP_D2I_POST) { 38 DH *dh = (DH *)*pval; 39 40 DH_clear_flags(dh, DH_FLAG_TYPE_MASK); 41 DH_set_flags(dh, DH_FLAG_TYPE_DH); 42 ossl_dh_cache_named_group(dh); 43 dh->dirty_cnt++; 44 } 45 return 1; 46} 47 48ASN1_SEQUENCE_cb(DHparams, dh_cb) = { 49 ASN1_SIMPLE(DH, params.p, BIGNUM), 50 ASN1_SIMPLE(DH, params.g, BIGNUM), 51 ASN1_OPT_EMBED(DH, length, ZINT32), 52} ASN1_SEQUENCE_END_cb(DH, DHparams) 53 54IMPLEMENT_ASN1_ENCODE_FUNCTIONS_fname(DH, DHparams, DHparams) 55 56/* 57 * Internal only structures for handling X9.42 DH: this gets translated to or 58 * from a DH structure straight away. 59 */ 60 61typedef struct { 62 ASN1_BIT_STRING *seed; 63 BIGNUM *counter; 64} int_dhvparams; 65 66typedef struct { 67 BIGNUM *p; 68 BIGNUM *q; 69 BIGNUM *g; 70 BIGNUM *j; 71 int_dhvparams *vparams; 72} int_dhx942_dh; 73 74ASN1_SEQUENCE(DHvparams) = { 75 ASN1_SIMPLE(int_dhvparams, seed, ASN1_BIT_STRING), 76 ASN1_SIMPLE(int_dhvparams, counter, BIGNUM) 77} static_ASN1_SEQUENCE_END_name(int_dhvparams, DHvparams) 78 79ASN1_SEQUENCE(DHxparams) = { 80 ASN1_SIMPLE(int_dhx942_dh, p, BIGNUM), 81 ASN1_SIMPLE(int_dhx942_dh, g, BIGNUM), 82 ASN1_SIMPLE(int_dhx942_dh, q, BIGNUM), 83 ASN1_OPT(int_dhx942_dh, j, BIGNUM), 84 ASN1_OPT(int_dhx942_dh, vparams, DHvparams), 85} static_ASN1_SEQUENCE_END_name(int_dhx942_dh, DHxparams) 86 87int_dhx942_dh *d2i_int_dhx(int_dhx942_dh **a, 88 const unsigned char **pp, long length); 89int i2d_int_dhx(const int_dhx942_dh *a, unsigned char **pp); 90 91IMPLEMENT_ASN1_ENCODE_FUNCTIONS_fname(int_dhx942_dh, DHxparams, int_dhx) 92 93DH *d2i_DHxparams(DH **a, const unsigned char **pp, long length) 94{ 95 FFC_PARAMS *params; 96 int_dhx942_dh *dhx = NULL; 97 DH *dh = NULL; 98 99 dh = DH_new(); 100 if (dh == NULL) 101 return NULL; 102 dhx = d2i_int_dhx(NULL, pp, length); 103 if (dhx == NULL) { 104 DH_free(dh); 105 return NULL; 106 } 107 108 if (a != NULL) { 109 DH_free(*a); 110 *a = dh; 111 } 112 113 params = &dh->params; 114 DH_set0_pqg(dh, dhx->p, dhx->q, dhx->g); 115 ossl_ffc_params_set0_j(params, dhx->j); 116 117 if (dhx->vparams != NULL) { 118 /* The counter has a maximum value of 4 * numbits(p) - 1 */ 119 size_t counter = (size_t)BN_get_word(dhx->vparams->counter); 120 ossl_ffc_params_set_validate_params(params, dhx->vparams->seed->data, 121 dhx->vparams->seed->length, 122 counter); 123 ASN1_BIT_STRING_free(dhx->vparams->seed); 124 BN_free(dhx->vparams->counter); 125 OPENSSL_free(dhx->vparams); 126 dhx->vparams = NULL; 127 } 128 129 OPENSSL_free(dhx); 130 DH_clear_flags(dh, DH_FLAG_TYPE_MASK); 131 DH_set_flags(dh, DH_FLAG_TYPE_DHX); 132 return dh; 133} 134 135int i2d_DHxparams(const DH *dh, unsigned char **pp) 136{ 137 int ret = 0; 138 int_dhx942_dh dhx; 139 int_dhvparams dhv = { NULL, NULL }; 140 ASN1_BIT_STRING seed; 141 size_t seedlen = 0; 142 const FFC_PARAMS *params = &dh->params; 143 int counter; 144 145 ossl_ffc_params_get0_pqg(params, (const BIGNUM **)&dhx.p, 146 (const BIGNUM **)&dhx.q, (const BIGNUM **)&dhx.g); 147 dhx.j = params->j; 148 ossl_ffc_params_get_validate_params(params, &seed.data, &seedlen, &counter); 149 seed.length = (int)seedlen; 150 151 if (counter != -1 && seed.data != NULL && seed.length > 0) { 152 seed.flags = ASN1_STRING_FLAG_BITS_LEFT; 153 dhv.seed = &seed; 154 dhv.counter = BN_new(); 155 if (dhv.counter == NULL) 156 return 0; 157 if (!BN_set_word(dhv.counter, (BN_ULONG)counter)) 158 goto err; 159 dhx.vparams = &dhv; 160 } else { 161 dhx.vparams = NULL; 162 } 163 ret = i2d_int_dhx(&dhx, pp); 164err: 165 BN_free(dhv.counter); 166 return ret; 167} 168