openssl/demos/pkey/EVP_PKEY_DSA_paramvalidate.c

203 lines
7.4 KiB
C

/*-
* Copyright 2022 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
/*
* Example showing how to validate DSA parameters.
*
* Proper FIPS 186-4 DSA (FFC) parameter validation requires that all
* the parameters used during parameter generation are supplied
* when doing the validation. Unfortunately saving DSA parameters as
* a PEM or DER file does not write out all required fields. Because
* of this the default provider normally only does a partial
* validation. The FIPS provider will however try to do a full
* validation. To force the default provider to use full
* validation the 'seed' that is output during generation must be
* added to the key. See doc/man7/EVP_PKEY-FFC for more information.
*/
#include <openssl/evp.h>
#include <openssl/core_names.h>
#include <openssl/pem.h>
#include "dsa.inc"
/* The following values were output from the EVP_PKEY_DSA_paramgen demo */
static const char dsapem[] =
"-----BEGIN DSA PARAMETERS-----\n"
"MIICLAKCAQEA1pobSR1FJ3+Tvi0J6Tk1PSV2owZey1Nuo847hGw/59VCS6RPQEqr\n"
"vp5fhbvBjupBeVGA/AMH6rI4i4h6jlhurrqH1CqUHVcDhJzxV668bMLiP3mIxg5o\n"
"9Yq8x6BnSOtH5Je0tpeE0/fEvvLjCwBUbwnwWxzjANcvDUEt9XYeRrtB2v52fr56\n"
"hVYz3wMMNog4CEDOLTvx7/84eVPuUeWDRQFH1EaHMdulP34KBcatEEpEZapkepng\n"
"nohm9sFSPQhq2utpkH7pNXdG0EILBtRDCvUpF5720a48LYofdggh2VEZfgElAGFk\n"
"dW/CkvyBDmGIzil5aTz4MMsdudaVYgzt6wIhAPsSGC42Qa+X0AFGvonb5nmfUVm/\n"
"8aC+tHk7Nb2AYLHXAoIBADx5C0H1+QHsmGKvuOaY+WKUt7aWUrEivD1zBMJAQ6bL\n"
"Wv9lbCq1CFHvVzojeOVpn872NqDEpkx4HTpvqhxWL5CkbN/HaGItsQzkD59AQg3v\n"
"4YsLlkesq9Jq6x/aWetJXWO36fszFv1gpD3NY3wliBvMYHx62jfc5suh9D3ZZvu7\n"
"PLGH4X4kcfzK/R2b0oVbEBjVTe5GMRYZRqnvfSW2f2fA7BzI1OL83UxDDe58cL2M\n"
"GcAoUYXOBAfZ37qLMm2juf+o5gCrT4CXfRPu6kbapt7V/YIc1nsNgeAOKKoFBHBQ\n"
"gc5u5G6G/j79FVoSDq9DYwTJcHPsU+eHj1uWHso1AjQ=\n"
"-----END DSA PARAMETERS-----\n";
static const char hexseed[] =
"cba30ccd905aa7675a0b81769704bf3c"
"ccf2ca1892b2eaf6b9e2b38d9bf6affc"
"42ada55986d8a1772b442770954d0b65";
const int gindex = 42;
const int pcounter = 363;
static const char digest[] = "SHA384";
/*
* Create a new dsa param key that is the combination of an existing param key
* plus extra parameters.
*/
EVP_PKEY_CTX *create_merged_key(EVP_PKEY *dsaparams, const OSSL_PARAM *newparams,
OSSL_LIB_CTX *libctx, const char *propq)
{
EVP_PKEY_CTX *out = NULL;
EVP_PKEY_CTX *ctx = NULL;
EVP_PKEY *pkey = NULL;
OSSL_PARAM *mergedparams = NULL;
OSSL_PARAM *loadedparams = NULL;
/* Specify EVP_PKEY_KEY_PUBLIC here if you have a public key */
if (EVP_PKEY_todata(dsaparams, EVP_PKEY_KEY_PARAMETERS, &loadedparams) <= 0) {
fprintf(stderr, "EVP_PKEY_todata() failed\n");
goto cleanup;
}
mergedparams = OSSL_PARAM_merge(loadedparams, newparams);
if (mergedparams == NULL) {
fprintf(stderr, "OSSL_PARAM_merge() failed\n");
goto cleanup;
}
ctx = EVP_PKEY_CTX_new_from_name(libctx, "DSA", propq);
if (ctx == NULL) {
fprintf(stderr, "EVP_PKEY_CTX_new_from_name() failed\n");
goto cleanup;
}
if (EVP_PKEY_fromdata_init(ctx) <= 0
|| EVP_PKEY_fromdata(ctx, &pkey,
EVP_PKEY_KEY_PARAMETERS, mergedparams) <= 0) {
fprintf(stderr, "EVP_PKEY_fromdata() failed\n");
goto cleanup;
}
out = EVP_PKEY_CTX_new_from_pkey(libctx, pkey, propq);
if (out == NULL) {
fprintf(stderr, "EVP_PKEY_CTX_new_from_pkey() failed\n");
goto cleanup;
}
cleanup:
EVP_PKEY_free(pkey);
OSSL_PARAM_free(loadedparams);
OSSL_PARAM_free(mergedparams);
EVP_PKEY_CTX_free(ctx);
return out;
}
int main(int argc, char **argv)
{
int rv = EXIT_FAILURE;
OSSL_LIB_CTX *libctx = NULL;
const char *propq = NULL;
EVP_PKEY *dsaparamskey = NULL;
EVP_PKEY_CTX *ctx = NULL;
EVP_PKEY_CTX *ctx1 = NULL;
EVP_PKEY_CTX *ctx2 = NULL;
BIO *in = NULL;
OSSL_PARAM params[6];
unsigned char seed[64];
size_t seedlen;
if (!OPENSSL_hexstr2buf_ex(seed, sizeof(seed), &seedlen, hexseed, '\0'))
goto cleanup;
/*
* This example loads the PEM data from a memory buffer
* Use BIO_new_fp() to load a PEM file instead
*/
in = BIO_new_mem_buf(dsapem, strlen(dsapem));
if (in == NULL) {
fprintf(stderr, "BIO_new_mem_buf() failed\n");
goto cleanup;
}
/* Load DSA params from pem data */
dsaparamskey = PEM_read_bio_Parameters_ex(in, NULL, libctx, propq);
if (dsaparamskey == NULL) {
fprintf(stderr, "Failed to load dsa params\n");
goto cleanup;
}
ctx = EVP_PKEY_CTX_new_from_pkey(libctx, dsaparamskey, propq);
if (ctx == NULL) {
fprintf(stderr, "EVP_PKEY_CTX_new_from_pkey() failed\n");
goto cleanup;
}
/*
* When using the default provider this only does a partial check to
* make sure that the values of p, q and g are ok.
* This will fail however if the FIPS provider is used since it does
* a proper FIPS 186-4 key validation which requires extra parameters
*/
if (EVP_PKEY_param_check(ctx) <= 0) {
fprintf(stderr, "Simple EVP_PKEY_param_check() failed \n");
goto cleanup;
}
/*
* Setup parameters that we want to add.
* For illustration purposes it deliberately omits a required parameter.
*/
params[0] = OSSL_PARAM_construct_utf8_string(OSSL_PKEY_PARAM_FFC_TYPE,
"fips186_4", 0);
/* Force it to do a proper validation by setting the seed */
params[1] = OSSL_PARAM_construct_octet_string(OSSL_PKEY_PARAM_FFC_SEED,
(void *)seed, seedlen);
params[2] = OSSL_PARAM_construct_int(OSSL_PKEY_PARAM_FFC_GINDEX, (int *)&gindex);
params[3] = OSSL_PARAM_construct_int(OSSL_PKEY_PARAM_FFC_PCOUNTER, (int *)&pcounter);
params[4] = OSSL_PARAM_construct_end();
/* generate a new key that is the combination of the existing key and the new params */
ctx1 = create_merged_key(dsaparamskey, params, libctx, propq);
if (ctx1 == NULL)
goto cleanup;
/* This will fail since not all the parameters used for key generation are added */
if (EVP_PKEY_param_check(ctx1) > 0) {
fprintf(stderr, "EVP_PKEY_param_check() should fail\n");
goto cleanup;
}
/*
* Add the missing parameters onto the end of the existing list of params
* If the default was used for the generation then this parameter is not
* needed
*/
params[4] = OSSL_PARAM_construct_utf8_string(OSSL_PKEY_PARAM_FFC_DIGEST,
(char *)digest, 0);
params[5] = OSSL_PARAM_construct_end();
ctx2 = create_merged_key(dsaparamskey, params, libctx, propq);
if (ctx2 == NULL)
goto cleanup;
if (EVP_PKEY_param_check(ctx2) <= 0) {
fprintf(stderr, "EVP_PKEY_param_check() failed\n");
goto cleanup;
}
if (!dsa_print_key(EVP_PKEY_CTX_get0_pkey(ctx2), 0, libctx, propq))
goto cleanup;
rv = EXIT_SUCCESS;
cleanup:
EVP_PKEY_free(dsaparamskey);
EVP_PKEY_CTX_free(ctx2);
EVP_PKEY_CTX_free(ctx1);
EVP_PKEY_CTX_free(ctx);
BIO_free(in);
return rv;
}