crypto/ffc/ffc_params.c

   1 /*
   2  * Copyright 2019-2020 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 <string.h> /* memset */
  11 #include "internal/ffc.h"
  12 #ifndef FIPS_MODE
  13 # include <openssl/asn1.h> /* ffc_params_print */
  14 #endif
  15
  16 void ffc_params_init(FFC_PARAMS *params)
  17 {
  18     memset(params, 0, sizeof(FFC_PARAMS));
  19     params->pcounter = -1;
  20 }
  21
  22 void ffc_params_cleanup(FFC_PARAMS *params)
  23 {
  24     BN_free(params->p);
  25     BN_free(params->q);
  26     BN_free(params->g);
  27     BN_free(params->j);
  28     OPENSSL_free(params->seed);
  29     ffc_params_init(params);
  30 }
  31
  32 void ffc_params_set0_pqg(FFC_PARAMS *d, BIGNUM *p, BIGNUM *q, BIGNUM *g)
  33 {
  34     if (p != NULL && p != d->p) {
  35         BN_free(d->p);
  36         d->p = p;
  37     }
  38     if (q != NULL && q != d->q) {
  39         BN_free(d->q);
  40         d->q = q;
  41     }
  42     if (g != NULL && g != d->g) {
  43         BN_free(d->g);
  44         d->g = g;
  45     }
  46 }
  47
  48 void ffc_params_get0_pqg(const FFC_PARAMS *d, const BIGNUM **p,
  49                          const BIGNUM **q, const BIGNUM **g)
  50 {
  51     if (p != NULL)
  52         *p = d->p;
  53     if (q != NULL)
  54         *q = d->q;
  55     if (g != NULL)
  56         *g = d->g;
  57 }
  58
  59
  60 /* j is the 'cofactor' that is optionally output for ASN1. */
  61 void ffc_params_set0_j(FFC_PARAMS *d, BIGNUM *j)
  62 {
  63     BN_free(d->j);
  64     d->j = NULL;
  65     if (j != NULL)
  66         d->j = j;
  67 }
  68
  69 int ffc_params_set_validate_params(FFC_PARAMS *params,
  70                                    const unsigned char *seed, size_t seedlen,
  71                                    int counter)
  72 {
  73     if (params == NULL)
  74         return 0;
  75
  76     if (params->seed != NULL)
  77         OPENSSL_free(params->seed);
  78
  79     if (seed != NULL && seedlen > 0) {
  80         params->seed = OPENSSL_memdup(seed, seedlen);
  81         if (params->seed == NULL)
  82             return 0;
  83         params->seedlen = seedlen;
  84     } else {
  85         params->seed = NULL;
  86         params->seedlen = 0;
  87     }
  88     params->pcounter = counter;
  89     return 1;
  90 }
  91
  92 void ffc_params_get_validate_params(const FFC_PARAMS *params,
  93                                     unsigned char **seed, size_t *seedlen,
  94                                     int *pcounter)
  95 {
  96     if (seed != NULL)
  97         *seed = params->seed;
  98     if (seedlen != NULL)
  99         *seedlen = params->seedlen;
 100     if (pcounter != NULL)
 101         *pcounter = params->pcounter;
 102 }
 103
 104 static int ffc_bn_cpy(BIGNUM **dst, const BIGNUM *src)
 105 {
 106     BIGNUM *a;
 107
 108     /*
 109      * If source is read only just copy the pointer, so
 110      * we don't have to reallocate it.
 111      */
 112     if (src == NULL)
 113         a = NULL;
 114     else if (BN_get_flags(src, BN_FLG_STATIC_DATA)
 115              && !BN_get_flags(src, BN_FLG_MALLOCED))
 116         a = (BIGNUM *)src;
 117     else if ((a = BN_dup(src)) == NULL)
 118         return 0;
 119     BN_clear_free(*dst);
 120     *dst = a;
 121     return 1;
 122 }
 123
 124 int ffc_params_copy(FFC_PARAMS *dst, const FFC_PARAMS *src)
 125 {
 126     if (!ffc_bn_cpy(&dst->p, src->p)
 127         || !ffc_bn_cpy(&dst->g, src->g)
 128         || !ffc_bn_cpy(&dst->q, src->q)
 129         || !ffc_bn_cpy(&dst->j, src->j))
 130         return 0;
 131
 132     OPENSSL_free(dst->seed);
 133     dst->seedlen = src->seedlen;
 134     if (src->seed != NULL) {
 135         dst->seed = OPENSSL_memdup(src->seed, src->seedlen);
 136         if  (dst->seed == NULL)
 137             return 0;
 138     } else {
 139         dst->seed = NULL;
 140     }
 141     dst->pcounter = src->pcounter;
 142     return 1;
 143 }
 144
 145 int ffc_params_cmp(const FFC_PARAMS *a, const FFC_PARAMS *b, int ignore_q)
 146 {
 147     return BN_cmp(a->p, b->p) == 0
 148            && BN_cmp(a->g, b->g) == 0
 149            && (ignore_q || BN_cmp(a->q, b->q) == 0); /* Note: q may be NULL */
 150 }
 151
 152 #ifndef FIPS_MODE
 153 int ffc_params_print(BIO *bp, const FFC_PARAMS *ffc, int indent)
 154 {
 155     if (!ASN1_bn_print(bp, "prime P:", ffc->p, NULL, indent))
 156         goto err;
 157     if (!ASN1_bn_print(bp, "generator G:", ffc->g, NULL, indent))
 158         goto err;
 159     if (ffc->q != NULL
 160         && !ASN1_bn_print(bp, "subgroup order Q:", ffc->q, NULL, indent))
 161         goto err;
 162     if (ffc->j != NULL
 163         && !ASN1_bn_print(bp, "subgroup factor:", ffc->j, NULL, indent))
 164         goto err;
 165     if (ffc->seed != NULL) {
 166         size_t i;
 167         BIO_indent(bp, indent, 128);
 168         BIO_puts(bp, "seed:");
 169         for (i = 0; i < ffc->seedlen; i++) {
 170             if ((i % 15) == 0) {
 171                 if (BIO_puts(bp, "\n") <= 0
 172                     || !BIO_indent(bp, indent + 4, 128))
 173                     goto err;
 174             }
 175             if (BIO_printf(bp, "%02x%s", ffc->seed[i],
 176                            ((i + 1) == ffc->seedlen) ? "" : ":") <= 0)
 177                 goto err;
 178         }
 179         if (BIO_write(bp, "\n", 1) <= 0)
 180             return 0;
 181     }
 182     if (ffc->pcounter != -1) {
 183         BIO_indent(bp, indent, 128);
 184         if (BIO_printf(bp, "counter: %d\n", ffc->pcounter) <= 0)
 185             goto err;
 186     }
 187     return 1;
 188 err:
 189     return 0;
 190 }
 191 #endif /* FIPS_MODE */