mbedtls/programs/pkey/key_app.c
Gilles Peskine 52cc2a6368 Use new mbedtls_ecp_keypair functions in sample programs
This eliminates the use of MBEDTLS_PRIVATE in sample programs to access
fields of an mbedtls_ecp_keypair structure.

When displaying elliptic curve points, the program now display the
coordinates in the standard form instead of the internal representation.

The auxiliary function show_ecp_key is present in three programs. It's more
complex than the previous code which was also triplicated. There's no good
place for such auxiliary functions that don't belong in the library and are
used in multiple sample programs.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2023-12-24 19:49:43 +01:00

368 lines
12 KiB
C

/*
* Key reading application
*
* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
*/
#include "mbedtls/build_info.h"
#include "mbedtls/platform.h"
#if defined(MBEDTLS_BIGNUM_C) && \
defined(MBEDTLS_PK_PARSE_C) && defined(MBEDTLS_FS_IO) && \
defined(MBEDTLS_ENTROPY_C) && defined(MBEDTLS_CTR_DRBG_C)
#include "mbedtls/error.h"
#include "mbedtls/rsa.h"
#include "mbedtls/pk.h"
#include "mbedtls/entropy.h"
#include "mbedtls/ctr_drbg.h"
#include <string.h>
#endif
#define MODE_NONE 0
#define MODE_PRIVATE 1
#define MODE_PUBLIC 2
#define DFL_MODE MODE_NONE
#define DFL_FILENAME "keyfile.key"
#define DFL_PASSWORD ""
#define DFL_PASSWORD_FILE ""
#define DFL_DEBUG_LEVEL 0
#define USAGE \
"\n usage: key_app param=<>...\n" \
"\n acceptable parameters:\n" \
" mode=private|public default: none\n" \
" filename=%%s default: keyfile.key\n" \
" password=%%s default: \"\"\n" \
" password_file=%%s default: \"\"\n" \
"\n"
#if !defined(MBEDTLS_BIGNUM_C) || \
!defined(MBEDTLS_PK_PARSE_C) || !defined(MBEDTLS_FS_IO) || \
!defined(MBEDTLS_ENTROPY_C) || !defined(MBEDTLS_CTR_DRBG_C)
int main(void)
{
mbedtls_printf("MBEDTLS_BIGNUM_C and/or "
"MBEDTLS_PK_PARSE_C and/or MBEDTLS_FS_IO and/or "
"MBEDTLS_ENTROPY_C and/or MBEDTLS_CTR_DRBG_C not defined.\n");
mbedtls_exit(0);
}
#else
#if defined(MBEDTLS_ECP_C)
static int show_ecp_key(const mbedtls_ecp_keypair *ecp, int has_private)
{
int ret = 0;
const mbedtls_ecp_curve_info *curve_info =
mbedtls_ecp_curve_info_from_grp_id(
mbedtls_ecp_keypair_get_group_id(ecp));
mbedtls_printf("curve: %s\n", curve_info->name);
mbedtls_ecp_group grp;
mbedtls_ecp_group_init(&grp);
mbedtls_mpi D;
mbedtls_mpi_init(&D);
mbedtls_ecp_point pt;
mbedtls_ecp_point_init(&pt);
mbedtls_mpi X, Y;
mbedtls_mpi_init(&X); mbedtls_mpi_init(&Y);
MBEDTLS_MPI_CHK(mbedtls_ecp_export(ecp, &grp,
(has_private ? &D : NULL),
&pt));
unsigned char point_bin[MBEDTLS_ECP_MAX_PT_LEN];
size_t len = 0;
MBEDTLS_MPI_CHK(mbedtls_ecp_point_write_binary(
&grp, &pt, MBEDTLS_ECP_PF_UNCOMPRESSED,
&len, point_bin, sizeof(point_bin)));
switch (mbedtls_ecp_get_type(&grp)) {
case MBEDTLS_ECP_TYPE_SHORT_WEIERSTRASS:
if ((len & 1) == 0 || point_bin[0] != 0x04) {
/* Point in an unxepected format. This shouldn't happen. */
ret = -1;
goto cleanup;
}
MBEDTLS_MPI_CHK(
mbedtls_mpi_read_binary(&X, point_bin + 1, len / 2));
MBEDTLS_MPI_CHK(
mbedtls_mpi_read_binary(&Y, point_bin + 1 + len / 2, len / 2));
mbedtls_mpi_write_file("X_Q: ", &X, 16, NULL);
mbedtls_mpi_write_file("Y_Q: ", &Y, 16, NULL);
break;
case MBEDTLS_ECP_TYPE_MONTGOMERY:
MBEDTLS_MPI_CHK(mbedtls_mpi_read_binary(&X, point_bin, len));
mbedtls_mpi_write_file("X_Q: ", &X, 16, NULL);
break;
default:
mbedtls_printf(
"This program does not yet support listing coordinates for this curve type.\n");
break;
}
if (has_private) {
mbedtls_mpi_write_file("D: ", &D, 16, NULL);
}
cleanup:
mbedtls_ecp_group_free(&grp);
mbedtls_mpi_free(&D);
mbedtls_ecp_point_free(&pt);
mbedtls_mpi_free(&X); mbedtls_mpi_free(&Y);
return ret;
}
#endif
/*
* global options
*/
struct options {
int mode; /* the mode to run the application in */
const char *filename; /* filename of the key file */
const char *password; /* password for the private key */
const char *password_file; /* password_file for the private key */
} opt;
int main(int argc, char *argv[])
{
int ret = 1;
int exit_code = MBEDTLS_EXIT_FAILURE;
char buf[1024];
int i;
char *p, *q;
const char *pers = "pkey/key_app";
mbedtls_entropy_context entropy;
mbedtls_ctr_drbg_context ctr_drbg;
mbedtls_pk_context pk;
mbedtls_mpi N, P, Q, D, E, DP, DQ, QP;
/*
* Set to sane values
*/
mbedtls_entropy_init(&entropy);
mbedtls_ctr_drbg_init(&ctr_drbg);
mbedtls_pk_init(&pk);
memset(buf, 0, sizeof(buf));
#if defined(MBEDTLS_USE_PSA_CRYPTO)
psa_status_t status = psa_crypto_init();
if (status != PSA_SUCCESS) {
mbedtls_fprintf(stderr, "Failed to initialize PSA Crypto implementation: %d\n",
(int) status);
goto cleanup;
}
#endif /* MBEDTLS_USE_PSA_CRYPTO */
mbedtls_mpi_init(&N); mbedtls_mpi_init(&P); mbedtls_mpi_init(&Q);
mbedtls_mpi_init(&D); mbedtls_mpi_init(&E); mbedtls_mpi_init(&DP);
mbedtls_mpi_init(&DQ); mbedtls_mpi_init(&QP);
if (argc < 2) {
usage:
mbedtls_printf(USAGE);
goto cleanup;
}
opt.mode = DFL_MODE;
opt.filename = DFL_FILENAME;
opt.password = DFL_PASSWORD;
opt.password_file = DFL_PASSWORD_FILE;
for (i = 1; i < argc; i++) {
p = argv[i];
if ((q = strchr(p, '=')) == NULL) {
goto usage;
}
*q++ = '\0';
if (strcmp(p, "mode") == 0) {
if (strcmp(q, "private") == 0) {
opt.mode = MODE_PRIVATE;
} else if (strcmp(q, "public") == 0) {
opt.mode = MODE_PUBLIC;
} else {
goto usage;
}
} else if (strcmp(p, "filename") == 0) {
opt.filename = q;
} else if (strcmp(p, "password") == 0) {
opt.password = q;
} else if (strcmp(p, "password_file") == 0) {
opt.password_file = q;
} else {
goto usage;
}
}
if (opt.mode == MODE_PRIVATE) {
if (strlen(opt.password) && strlen(opt.password_file)) {
mbedtls_printf("Error: cannot have both password and password_file\n");
goto usage;
}
if (strlen(opt.password_file)) {
FILE *f;
mbedtls_printf("\n . Loading the password file ...");
if ((f = fopen(opt.password_file, "rb")) == NULL) {
mbedtls_printf(" failed\n ! fopen returned NULL\n");
goto cleanup;
}
if (fgets(buf, sizeof(buf), f) == NULL) {
fclose(f);
mbedtls_printf("Error: fgets() failed to retrieve password\n");
goto cleanup;
}
fclose(f);
i = (int) strlen(buf);
if (buf[i - 1] == '\n') {
buf[i - 1] = '\0';
}
if (buf[i - 2] == '\r') {
buf[i - 2] = '\0';
}
opt.password = buf;
}
/*
* 1.1. Load the key
*/
mbedtls_printf("\n . Loading the private key ...");
fflush(stdout);
if ((ret = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func, &entropy,
(const unsigned char *) pers,
strlen(pers))) != 0) {
mbedtls_printf(" failed\n ! mbedtls_ctr_drbg_seed returned -0x%04x\n",
(unsigned int) -ret);
goto cleanup;
}
ret = mbedtls_pk_parse_keyfile(&pk, opt.filename, opt.password,
mbedtls_ctr_drbg_random, &ctr_drbg);
if (ret != 0) {
mbedtls_printf(" failed\n ! mbedtls_pk_parse_keyfile returned -0x%04x\n",
(unsigned int) -ret);
goto cleanup;
}
mbedtls_printf(" ok\n");
/*
* 1.2 Print the key
*/
mbedtls_printf(" . Key information ...\n");
#if defined(MBEDTLS_RSA_C)
if (mbedtls_pk_get_type(&pk) == MBEDTLS_PK_RSA) {
mbedtls_rsa_context *rsa = mbedtls_pk_rsa(pk);
if ((ret = mbedtls_rsa_export(rsa, &N, &P, &Q, &D, &E)) != 0 ||
(ret = mbedtls_rsa_export_crt(rsa, &DP, &DQ, &QP)) != 0) {
mbedtls_printf(" failed\n ! could not export RSA parameters\n\n");
goto cleanup;
}
MBEDTLS_MPI_CHK(mbedtls_mpi_write_file("N: ", &N, 16, NULL));
MBEDTLS_MPI_CHK(mbedtls_mpi_write_file("E: ", &E, 16, NULL));
MBEDTLS_MPI_CHK(mbedtls_mpi_write_file("D: ", &D, 16, NULL));
MBEDTLS_MPI_CHK(mbedtls_mpi_write_file("P: ", &P, 16, NULL));
MBEDTLS_MPI_CHK(mbedtls_mpi_write_file("Q: ", &Q, 16, NULL));
MBEDTLS_MPI_CHK(mbedtls_mpi_write_file("DP: ", &DP, 16, NULL));
MBEDTLS_MPI_CHK(mbedtls_mpi_write_file("DQ: ", &DQ, 16, NULL));
MBEDTLS_MPI_CHK(mbedtls_mpi_write_file("QP: ", &QP, 16, NULL));
} else
#endif
#if defined(MBEDTLS_ECP_C)
if (mbedtls_pk_get_type(&pk) == MBEDTLS_PK_ECKEY) {
if (show_ecp_key(mbedtls_pk_ec(pk), 1) != 0) {
mbedtls_printf(" failed\n ! could not export ECC parameters\n\n");
goto cleanup;
}
} else
#endif
{
mbedtls_printf("Do not know how to print key information for this type\n");
goto cleanup;
}
} else if (opt.mode == MODE_PUBLIC) {
/*
* 1.1. Load the key
*/
mbedtls_printf("\n . Loading the public key ...");
fflush(stdout);
ret = mbedtls_pk_parse_public_keyfile(&pk, opt.filename);
if (ret != 0) {
mbedtls_printf(" failed\n ! mbedtls_pk_parse_public_keyfile returned -0x%04x\n",
(unsigned int) -ret);
goto cleanup;
}
mbedtls_printf(" ok\n");
mbedtls_printf(" . Key information ...\n");
#if defined(MBEDTLS_RSA_C)
if (mbedtls_pk_get_type(&pk) == MBEDTLS_PK_RSA) {
mbedtls_rsa_context *rsa = mbedtls_pk_rsa(pk);
if ((ret = mbedtls_rsa_export(rsa, &N, NULL, NULL,
NULL, &E)) != 0) {
mbedtls_printf(" failed\n ! could not export RSA parameters\n\n");
goto cleanup;
}
MBEDTLS_MPI_CHK(mbedtls_mpi_write_file("N: ", &N, 16, NULL));
MBEDTLS_MPI_CHK(mbedtls_mpi_write_file("E: ", &E, 16, NULL));
} else
#endif
#if defined(MBEDTLS_ECP_C)
if (mbedtls_pk_get_type(&pk) == MBEDTLS_PK_ECKEY) {
if (show_ecp_key(mbedtls_pk_ec(pk), 0) != 0) {
mbedtls_printf(" failed\n ! could not export ECC parameters\n\n");
goto cleanup;
}
} else
#endif
{
mbedtls_printf("Do not know how to print key information for this type\n");
goto cleanup;
}
} else {
goto usage;
}
exit_code = MBEDTLS_EXIT_SUCCESS;
cleanup:
#if defined(MBEDTLS_ERROR_C)
if (exit_code != MBEDTLS_EXIT_SUCCESS) {
mbedtls_strerror(ret, buf, sizeof(buf));
mbedtls_printf(" ! Last error was: %s\n", buf);
}
#endif
mbedtls_ctr_drbg_free(&ctr_drbg);
mbedtls_entropy_free(&entropy);
mbedtls_pk_free(&pk);
#if defined(MBEDTLS_USE_PSA_CRYPTO)
mbedtls_psa_crypto_free();
#endif /* MBEDTLS_USE_PSA_CRYPTO */
mbedtls_mpi_free(&N); mbedtls_mpi_free(&P); mbedtls_mpi_free(&Q);
mbedtls_mpi_free(&D); mbedtls_mpi_free(&E); mbedtls_mpi_free(&DP);
mbedtls_mpi_free(&DQ); mbedtls_mpi_free(&QP);
mbedtls_exit(exit_code);
}
#endif /* MBEDTLS_BIGNUM_C && MBEDTLS_PK_PARSE_C && MBEDTLS_FS_IO &&
MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C */