providers/implementations/keymgmt/rsa_kmgmt.c

   1 /*
   2  * Copyright 2019 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 #include <openssl/core_numbers.h>
  11 #include <openssl/core_names.h>
  12 #include <openssl/bn.h>
  13 #include <openssl/rsa.h>
  14 #include <openssl/params.h>
  15 #include <openssl/types.h>
  16 #include "internal/param_build.h"
  17 #include "prov/implementations.h"
  18 #include "prov/providercommon.h"
  19 #include "crypto/rsa.h"
  20
  21 static OSSL_OP_keymgmt_importkey_fn rsa_importkey;
  22 static OSSL_OP_keymgmt_exportkey_fn rsa_exportkey;
  23 static OSSL_OP_keymgmt_get_key_params_fn rsa_get_key_params;
  24
  25 DEFINE_STACK_OF(BIGNUM)
  26 DEFINE_SPECIAL_STACK_OF_CONST(BIGNUM_const, BIGNUM)
  27
  28 static int collect_numbers(STACK_OF(BIGNUM) *numbers,
  29                            const OSSL_PARAM params[], const char *key)
  30 {
  31     const OSSL_PARAM *p = NULL;
  32
  33     if (numbers == NULL)
  34         return 0;
  35
  36     for (p = params; (p = OSSL_PARAM_locate_const(p, key)) != NULL; p++) {
  37         BIGNUM *tmp = NULL;
  38
  39         if (!OSSL_PARAM_get_BN(p, &tmp))
  40             return 0;
  41         sk_BIGNUM_push(numbers, tmp);
  42     }
  43
  44     return 1;
  45 }
  46
  47 static int params_to_key(RSA *rsa, const OSSL_PARAM params[])
  48 {
  49     const OSSL_PARAM *param_n, *param_e,  *param_d;
  50     BIGNUM *n = NULL, *e = NULL, *d = NULL;
  51     STACK_OF(BIGNUM) *factors = NULL, *exps = NULL, *coeffs = NULL;
  52     int is_private = 0;
  53
  54     if (rsa == NULL)
  55         return 0;
  56
  57     param_n = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_RSA_N);
  58     param_e = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_RSA_E);
  59     param_d = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_RSA_D);
  60
  61     if ((param_n != NULL && !OSSL_PARAM_get_BN(param_n, &n))
  62         || (param_e != NULL && !OSSL_PARAM_get_BN(param_e, &e))
  63         || (param_d != NULL && !OSSL_PARAM_get_BN(param_d, &d)))
  64         goto err;
  65
  66     is_private = (d != NULL);
  67
  68     if (!RSA_set0_key(rsa, n, e, d))
  69         goto err;
  70     n = e = d = NULL;
  71
  72     if (is_private) {
  73         if (!collect_numbers(factors = sk_BIGNUM_new_null(), params,
  74                              OSSL_PKEY_PARAM_RSA_FACTOR)
  75             || !collect_numbers(exps = sk_BIGNUM_new_null(), params,
  76                                 OSSL_PKEY_PARAM_RSA_EXPONENT)
  77             || !collect_numbers(coeffs = sk_BIGNUM_new_null(), params,
  78                                 OSSL_PKEY_PARAM_RSA_COEFFICIENT))
  79             goto err;
  80
  81         /* It's ok if this private key just has n, e and d */
  82         if (sk_BIGNUM_num(factors) != 0
  83             && !rsa_set0_all_params(rsa, factors, exps, coeffs))
  84             goto err;
  85     }
  86
  87     sk_BIGNUM_free(factors);
  88     sk_BIGNUM_free(exps);
  89     sk_BIGNUM_free(coeffs);
  90     return 1;
  91
  92  err:
  93     BN_free(n);
  94     BN_free(e);
  95     BN_free(d);
  96     sk_BIGNUM_pop_free(factors, BN_free);
  97     sk_BIGNUM_pop_free(exps, BN_free);
  98     sk_BIGNUM_pop_free(coeffs, BN_free);
  99     return 0;
 100 }
 101
 102 static int export_numbers(OSSL_PARAM_BLD *tmpl, const char *key,
 103                           STACK_OF(BIGNUM_const) *numbers)
 104 {
 105     int i, nnum;
 106
 107     if (numbers == NULL)
 108         return 0;
 109
 110     nnum = sk_BIGNUM_const_num(numbers);
 111
 112     for (i = 0; i < nnum; i++) {
 113         if (!ossl_param_bld_push_BN(tmpl, key,
 114                                     sk_BIGNUM_const_value(numbers, i)))
 115             return 0;
 116     }
 117
 118     return 1;
 119 }
 120
 121 static int key_to_params(RSA *rsa, OSSL_PARAM_BLD *tmpl)
 122 {
 123     int ret = 0;
 124     const BIGNUM *rsa_d = NULL, *rsa_n = NULL, *rsa_e = NULL;
 125     STACK_OF(BIGNUM_const) *factors = sk_BIGNUM_const_new_null();
 126     STACK_OF(BIGNUM_const) *exps = sk_BIGNUM_const_new_null();
 127     STACK_OF(BIGNUM_const) *coeffs = sk_BIGNUM_const_new_null();
 128
 129     if (rsa == NULL || factors == NULL || exps == NULL || coeffs == NULL)
 130         goto err;
 131
 132     RSA_get0_key(rsa, &rsa_n, &rsa_e, &rsa_d);
 133     rsa_get0_all_params(rsa, factors, exps, coeffs);
 134
 135     if (rsa_n != NULL
 136         && !ossl_param_bld_push_BN(tmpl, OSSL_PKEY_PARAM_RSA_N, rsa_n))
 137         goto err;
 138     if (rsa_e != NULL
 139         && !ossl_param_bld_push_BN(tmpl, OSSL_PKEY_PARAM_RSA_E, rsa_e))
 140         goto err;
 141     if (rsa_d != NULL
 142         && !ossl_param_bld_push_BN(tmpl, OSSL_PKEY_PARAM_RSA_D, rsa_d))
 143         goto err;
 144
 145     if (!export_numbers(tmpl, OSSL_PKEY_PARAM_RSA_FACTOR, factors)
 146         || !export_numbers(tmpl, OSSL_PKEY_PARAM_RSA_EXPONENT, exps)
 147         || !export_numbers(tmpl, OSSL_PKEY_PARAM_RSA_COEFFICIENT, coeffs))
 148         goto err;
 149
 150     ret = 1;
 151  err:
 152     sk_BIGNUM_const_free(factors);
 153     sk_BIGNUM_const_free(exps);
 154     sk_BIGNUM_const_free(coeffs);
 155     return ret;
 156 }
 157
 158 static void *rsa_importkey(void *provctx, const OSSL_PARAM params[])
 159 {
 160     RSA *rsa;
 161
 162     if ((rsa = RSA_new()) == NULL
 163         || !params_to_key(rsa, params)) {
 164         RSA_free(rsa);
 165         rsa = NULL;
 166     }
 167     return rsa;
 168 }
 169
 170 static int rsa_exportkey(void *key, OSSL_CALLBACK *param_callback, void *cbarg)
 171 {
 172     RSA *rsa = key;
 173     OSSL_PARAM_BLD tmpl;
 174     OSSL_PARAM *params = NULL;
 175     int ret;
 176
 177     ossl_param_bld_init(&tmpl);
 178     if (rsa == NULL
 179         || !key_to_params(rsa, &tmpl)
 180         || (params = ossl_param_bld_to_param(&tmpl)) == NULL)
 181         return 0;
 182     ret = param_callback(params, cbarg);
 183     ossl_param_bld_free(params);
 184     return ret;
 185 }
 186
 187 /*
 188  * This provider can export everything in an RSA key, so we use the exact
 189  * same type description for export as for import.  Other providers might
 190  * choose to import full keys, but only export the public parts, and will
 191  * therefore have the importkey_types and importkey_types functions return
 192  * different arrays.
 193  */
 194 static const OSSL_PARAM rsa_key_types[] = {
 195     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_N, NULL, 0),
 196     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_E, NULL, 0),
 197     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_D, NULL, 0),
 198     /* We tolerate up to 10 factors... */
 199     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_FACTOR, NULL, 0),
 200     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_FACTOR, NULL, 0),
 201     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_FACTOR, NULL, 0),
 202     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_FACTOR, NULL, 0),
 203     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_FACTOR, NULL, 0),
 204     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_FACTOR, NULL, 0),
 205     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_FACTOR, NULL, 0),
 206     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_FACTOR, NULL, 0),
 207     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_FACTOR, NULL, 0),
 208     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_FACTOR, NULL, 0),
 209     /* ..., up to 10 CRT exponents... */
 210     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_EXPONENT, NULL, 0),
 211     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_EXPONENT, NULL, 0),
 212     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_EXPONENT, NULL, 0),
 213     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_EXPONENT, NULL, 0),
 214     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_EXPONENT, NULL, 0),
 215     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_EXPONENT, NULL, 0),
 216     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_EXPONENT, NULL, 0),
 217     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_EXPONENT, NULL, 0),
 218     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_EXPONENT, NULL, 0),
 219     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_EXPONENT, NULL, 0),
 220     /* ..., and up to 9 CRT coefficients */
 221     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_COEFFICIENT, NULL, 0),
 222     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_COEFFICIENT, NULL, 0),
 223     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_COEFFICIENT, NULL, 0),
 224     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_COEFFICIENT, NULL, 0),
 225     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_COEFFICIENT, NULL, 0),
 226     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_COEFFICIENT, NULL, 0),
 227     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_COEFFICIENT, NULL, 0),
 228     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_COEFFICIENT, NULL, 0),
 229     OSSL_PARAM_BN(OSSL_PKEY_PARAM_RSA_COEFFICIENT, NULL, 0),
 230 };
 231 /*
 232  * We lied about the amount of factors, exponents and coefficients, the
 233  * export and import functions can really deal with an infinite amount
 234  * of these numbers.  However, RSA keys with too many primes are futile,
 235  * so we at least pretend to have some limits.
 236  */
 237
 238 static const OSSL_PARAM *rsa_exportkey_types(void)
 239 {
 240     return rsa_key_types;
 241 }
 242
 243 static const OSSL_PARAM *rsa_importkey_types(void)
 244 {
 245     return rsa_key_types;
 246 }
 247
 248 static int rsa_get_key_params(void *key, OSSL_PARAM params[])
 249 {
 250     RSA *rsa = key;
 251     OSSL_PARAM *p;
 252
 253     if ((p = OSSL_PARAM_locate(params, OSSL_PKEY_PARAM_BITS)) != NULL
 254         && !OSSL_PARAM_set_int(p, RSA_bits(rsa)))
 255         return 0;
 256     if ((p = OSSL_PARAM_locate(params, OSSL_PKEY_PARAM_SECURITY_BITS)) != NULL
 257         && !OSSL_PARAM_set_int(p, RSA_security_bits(rsa)))
 258         return 0;
 259     if ((p = OSSL_PARAM_locate(params, OSSL_PKEY_PARAM_MAX_SIZE)) != NULL
 260         && !OSSL_PARAM_set_int(p, RSA_size(rsa)))
 261         return 0;
 262     return 1;
 263 }
 264
 265 const OSSL_DISPATCH rsa_keymgmt_functions[] = {
 266     { OSSL_FUNC_KEYMGMT_IMPORTKEY, (void (*)(void))rsa_importkey },
 267     { OSSL_FUNC_KEYMGMT_IMPORTKEY_TYPES, (void (*)(void))rsa_importkey_types },
 268     { OSSL_FUNC_KEYMGMT_EXPORTKEY, (void (*)(void))rsa_exportkey },
 269     { OSSL_FUNC_KEYMGMT_EXPORTKEY_TYPES, (void (*)(void))rsa_exportkey_types },
 270     { OSSL_FUNC_KEYMGMT_FREEKEY, (void (*)(void))RSA_free },
 271     { OSSL_FUNC_KEYMGMT_GET_KEY_PARAMS,  (void (*) (void))rsa_get_key_params },
 272     { 0, NULL }
 273 };