/*
* Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (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
*/
#include <openssl/opensslconf.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <string.h>
#include "apps.h"
#include "progs.h"
#include <openssl/bio.h>
#include <openssl/err.h>
#include <openssl/bn.h>
#include <openssl/dsa.h>
#include <openssl/x509.h>
#include <openssl/pem.h>
static int dsa_cb(int p, int n, BN_GENCB *cb);
typedef enum OPTION_choice {
OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,
OPT_INFORM, OPT_OUTFORM, OPT_IN, OPT_OUT, OPT_TEXT, OPT_C,
OPT_NOOUT, OPT_GENKEY, OPT_ENGINE, OPT_R_ENUM
} OPTION_CHOICE;
const OPTIONS dsaparam_options[] = {
{"help", OPT_HELP, '-', "Display this summary"},
{"inform", OPT_INFORM, 'F', "Input format - DER or PEM"},
{"in", OPT_IN, '<', "Input file"},
{"outform", OPT_OUTFORM, 'F', "Output format - DER or PEM"},
{"out", OPT_OUT, '>', "Output file"},
{"text", OPT_TEXT, '-', "Print as text"},
{"C", OPT_C, '-', "Output C code"},
{"noout", OPT_NOOUT, '-', "No output"},
{"genkey", OPT_GENKEY, '-', "Generate a DSA key"},
OPT_R_OPTIONS,
#ifndef OPENSSL_NO_ENGINE
{"engine", OPT_ENGINE, 's', "Use engine e, possibly a hardware device"},
#endif
{NULL}
};
int dsaparam_main(int argc, char **argv)
{
ENGINE *e = NULL;
DSA *dsa = NULL;
BIO *in = NULL, *out = NULL;
BN_GENCB *cb = NULL;
int numbits = -1, num = 0, genkey = 0;
int informat = FORMAT_PEM, outformat = FORMAT_PEM, noout = 0, C = 0;
int ret = 1, i, text = 0, private = 0;
char *infile = NULL, *outfile = NULL, *prog;
OPTION_CHOICE o;
prog = opt_init(argc, argv, dsaparam_options);
while ((o = opt_next()) != OPT_EOF) {
switch (o) {
case OPT_EOF:
case OPT_ERR:
opthelp:
BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
goto end;
case OPT_HELP:
opt_help(dsaparam_options);
ret = 0;
goto end;
case OPT_INFORM:
if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &informat))
goto opthelp;
break;
case OPT_IN:
infile = opt_arg();
break;
case OPT_OUTFORM:
if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &outformat))
goto opthelp;
break;
case OPT_OUT:
outfile = opt_arg();
break;
case OPT_ENGINE:
e = setup_engine(opt_arg(), 0);
break;
case OPT_TEXT:
text = 1;
break;
case OPT_C:
C = 1;
break;
case OPT_GENKEY:
genkey = 1;
break;
case OPT_R_CASES:
if (!opt_rand(o))
goto end;
break;
case OPT_NOOUT:
noout = 1;
break;
}
}
argc = opt_num_rest();
argv = opt_rest();
if (argc == 1) {
if (!opt_int(argv[0], &num) || num < 0)
goto end;
/* generate a key */
numbits = num;
}
private = genkey ? 1 : 0;
in = bio_open_default(infile, 'r', informat);
if (in == NULL)
goto end;
out = bio_open_owner(outfile, outformat, private);
if (out == NULL)
goto end;
if (numbits > 0) {
if (numbits > OPENSSL_DSA_MAX_MODULUS_BITS)
BIO_printf(bio_err,
"Warning: It is not recommended to use more than %d bit for DSA keys.\n"
" Your key size is %d! Larger key size may behave not as expected.\n",
OPENSSL_DSA_MAX_MODULUS_BITS, numbits);
cb = BN_GENCB_new();
if (cb == NULL) {
BIO_printf(bio_err, "Error allocating BN_GENCB object\n");
goto end;
}
BN_GENCB_set(cb, dsa_cb, bio_err);
dsa = DSA_new();
if (dsa == NULL) {
BIO_printf(bio_err, "Error allocating DSA object\n");
goto end;
}
BIO_printf(bio_err, "Generating DSA parameters, %d bit long prime\n",
num);
BIO_printf(bio_err, "This could take some time\n");
if (!DSA_generate_parameters_ex(dsa, num, NULL, 0, NULL, NULL, cb)) {
ERR_print_errors(bio_err);
BIO_printf(bio_err, "Error, DSA key generation failed\n");
goto end;
}
} else if (informat == FORMAT_ASN1) {
dsa = d2i_DSAparams_bio(in, NULL);
} else {
dsa = PEM_read_bio_DSAparams(in, NULL, NULL, NULL);
}
if (dsa == NULL) {
BIO_printf(bio_err, "unable to load DSA parameters\n");
ERR_print_errors(bio_err);
goto end;
}
if (text) {
DSAparams_print(out, dsa);
}
if (C) {
const BIGNUM *p = NULL, *q = NULL, *g = NULL;
unsigned char *data;
int len, bits_p;
DSA_get0_pqg(dsa, &p, &q, &g);
len = BN_num_bytes(p);
bits_p = BN_num_bits(p);
data = app_malloc(len + 20, "BN space");
BIO_printf(bio_out, "static DSA *get_dsa%d(void)\n{\n", bits_p);
print_bignum_var(bio_out, p, "dsap", bits_p, data);
print_bignum_var(bio_out, q, "dsaq", bits_p, data);
print_bignum_var(bio_out, g, "dsag", bits_p, data);
BIO_printf(bio_out, " DSA *dsa = DSA_new();\n"
" BIGNUM *p, *q, *g;\n"
"\n");
BIO_printf(bio_out, " if (dsa == NULL)\n"
" return NULL;\n");
BIO_printf(bio_out, " if (!DSA_set0_pqg(dsa, p = BN_bin2bn(dsap_%d, sizeof(dsap_%d), NULL),\n",
bits_p, bits_p);
BIO_printf(bio_out, " q = BN_bin2bn(dsaq_%d, sizeof(dsaq_%d), NULL),\n",
bits_p, bits_p);
BIO_printf(bio_out, " g = BN_bin2bn(dsag_%d, sizeof(dsag_%d), NULL))) {\n",
bits_p, bits_p);
BIO_printf(bio_out, " DSA_free(dsa);\n"
" BN_free(p);\n"
" BN_free(q);\n"
" BN_free(g);\n"
" return NULL;\n"
" }\n"
" return dsa;\n}\n");
OPENSSL_free(data);
}
if (outformat == FORMAT_ASN1 && genkey)
noout = 1;
if (!noout) {
if (outformat == FORMAT_ASN1)
i = i2d_DSAparams_bio(out, dsa);
else
i = PEM_write_bio_DSAparams(out, dsa);
if (!i) {
BIO_printf(bio_err, "unable to write DSA parameters\n");
ERR_print_errors(bio_err);
goto end;
}
}
if (genkey) {
DSA *dsakey;
if ((dsakey = DSAparams_dup(dsa)) == NULL)
goto end;
if (!DSA_generate_key(dsakey)) {
ERR_print_errors(bio_err);
DSA_free(dsakey);
goto end;
}
assert(private);
if (outformat == FORMAT_ASN1)
i = i2d_DSAPrivateKey_bio(out, dsakey);
else
i = PEM_write_bio_DSAPrivateKey(out, dsakey, NULL, NULL, 0, NULL,
NULL);
DSA_free(dsakey);
}
ret = 0;
end:
BN_GENCB_free(cb);
BIO_free(in);
BIO_free_all(out);
DSA_free(dsa);
release_engine(e);
return ret;
}
static int dsa_cb(int p, int n, BN_GENCB *cb)
{
static const char symbols[] = ".+*\n";
char c = (p >= 0 && (size_t)p < sizeof(symbols) - 1) ? symbols[p] : '?';
BIO_write(BN_GENCB_get_arg(cb), &c, 1);
(void)BIO_flush(BN_GENCB_get_arg(cb));
return 1;
}