openwrt/package/utils/px5g/px5g.c

327 lines
8.4 KiB
C

/*
* px5g - Embedded x509 key and certificate generator based on PolarSSL
*
* Copyright (C) 2009 Steven Barth <steven@midlink.org>
* Copyright (C) 2014 Felix Fietkau <nbd@nbd.name>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License, version 2.1 as published by the Free Software Foundation.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA
*/
#include <sys/types.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <limits.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdbool.h>
#include <mbedtls/bignum.h>
#include <mbedtls/x509_crt.h>
#include <mbedtls/ecp.h>
#include <mbedtls/rsa.h>
#include <mbedtls/pk.h>
#define PX5G_VERSION "0.2"
#define PX5G_COPY "Copyright (c) 2009 Steven Barth <steven@midlink.org>"
#define PX5G_LICENSE "Licensed under the GNU Lesser General Public License v2.1"
static int urandom_fd;
static char buf[16384];
static int _urandom(void *ctx, unsigned char *out, size_t len)
{
read(urandom_fd, out, len);
return 0;
}
static void write_file(const char *path, int len, bool pem)
{
FILE *f = stdout;
const char *buf_start = buf;
if (!pem)
buf_start += sizeof(buf) - len;
if (!len) {
fprintf(stderr, "No data to write\n");
exit(1);
}
if (!f) {
fprintf(stderr, "error: I/O error\n");
exit(1);
}
if (path)
f = fopen(path, "w");
fwrite(buf_start, 1, len, f);
fclose(f);
}
static mbedtls_ecp_group_id ecp_curve(const char *name)
{
const mbedtls_ecp_curve_info *curve_info;
if (!strcmp(name, "P-256"))
return MBEDTLS_ECP_DP_SECP256R1;
else if (!strcmp(name, "P-384"))
return MBEDTLS_ECP_DP_SECP384R1;
else if (!strcmp(name, "P-521"))
return MBEDTLS_ECP_DP_SECP521R1;
curve_info = mbedtls_ecp_curve_info_from_name(name);
if (curve_info == NULL)
return MBEDTLS_ECP_DP_NONE;
else
return curve_info->grp_id;
}
static void write_key(mbedtls_pk_context *key, const char *path, bool pem)
{
int len = 0;
if (pem) {
if (mbedtls_pk_write_key_pem(key, (void *) buf, sizeof(buf)) == 0)
len = strlen(buf);
} else {
len = mbedtls_pk_write_key_der(key, (void *) buf, sizeof(buf));
if (len < 0)
len = 0;
}
write_file(path, len, pem);
}
static void gen_key(mbedtls_pk_context *key, bool rsa, int ksize, int exp,
mbedtls_ecp_group_id curve, bool pem)
{
mbedtls_pk_init(key);
if (rsa) {
fprintf(stderr, "Generating RSA private key, %i bit long modulus\n", ksize);
mbedtls_pk_setup(key, mbedtls_pk_info_from_type(MBEDTLS_PK_RSA));
if (!mbedtls_rsa_gen_key(mbedtls_pk_rsa(*key), _urandom, NULL, ksize, exp))
return;
} else {
fprintf(stderr, "Generating EC private key\n");
mbedtls_pk_setup(key, mbedtls_pk_info_from_type(MBEDTLS_PK_ECKEY));
if (!mbedtls_ecp_gen_key(curve, mbedtls_pk_ec(*key), _urandom, NULL))
return;
}
fprintf(stderr, "error: key generation failed\n");
exit(1);
}
int dokey(bool rsa, char **arg)
{
mbedtls_pk_context key;
unsigned int ksize = 512;
int exp = 65537;
char *path = NULL;
bool pem = true;
mbedtls_ecp_group_id curve = MBEDTLS_ECP_DP_SECP256R1;
while (*arg && **arg == '-') {
if (!strcmp(*arg, "-out") && arg[1]) {
path = arg[1];
arg++;
} else if (!strcmp(*arg, "-3")) {
exp = 3;
} else if (!strcmp(*arg, "-der")) {
pem = false;
}
arg++;
}
if (*arg && rsa) {
ksize = (unsigned int)atoi(*arg);
} else if (*arg) {
curve = ecp_curve((const char *)*arg);
if (curve == MBEDTLS_ECP_DP_NONE) {
fprintf(stderr, "error: invalid curve name: %s\n", *arg);
return 1;
}
}
gen_key(&key, rsa, ksize, exp, curve, pem);
write_key(&key, path, pem);
mbedtls_pk_free(&key);
return 0;
}
int selfsigned(char **arg)
{
mbedtls_pk_context key;
mbedtls_x509write_cert cert;
mbedtls_mpi serial;
char *subject = "";
unsigned int ksize = 512;
int exp = 65537;
unsigned int days = 30;
char *keypath = NULL, *certpath = NULL;
bool pem = true;
time_t from = time(NULL), to;
char fstr[20], tstr[20], sstr[17];
int len;
bool rsa = true;
mbedtls_ecp_group_id curve = MBEDTLS_ECP_DP_SECP256R1;
while (*arg && **arg == '-') {
if (!strcmp(*arg, "-der")) {
pem = false;
} else if (!strcmp(*arg, "-newkey") && arg[1]) {
if (!strncmp(arg[1], "rsa:", 4)) {
rsa = true;
ksize = (unsigned int)atoi(arg[1] + 4);
} else if (!strcmp(arg[1], "ec")) {
rsa = false;
} else {
fprintf(stderr, "error: invalid algorithm\n");
return 1;
}
arg++;
} else if (!strcmp(*arg, "-days") && arg[1]) {
days = (unsigned int)atoi(arg[1]);
arg++;
} else if (!strcmp(*arg, "-pkeyopt") && arg[1]) {
if (strncmp(arg[1], "ec_paramgen_curve:", 18)) {
fprintf(stderr, "error: invalid pkey option: %s\n", arg[1]);
return 1;
}
curve = ecp_curve((const char *)(arg[1] + 18));
if (curve == MBEDTLS_ECP_DP_NONE) {
fprintf(stderr, "error: invalid curve name: %s\n", arg[1] + 18);
return 1;
}
arg++;
} else if (!strcmp(*arg, "-keyout") && arg[1]) {
keypath = arg[1];
arg++;
} else if (!strcmp(*arg, "-out") && arg[1]) {
certpath = arg[1];
arg++;
} else if (!strcmp(*arg, "-subj") && arg[1]) {
if (arg[1][0] != '/' || strchr(arg[1], ';')) {
fprintf(stderr, "error: invalid subject");
return 1;
}
subject = calloc(strlen(arg[1]) + 1, 1);
char *oldc = arg[1] + 1, *newc = subject, *delim;
do {
delim = strchr(oldc, '=');
if (!delim) {
fprintf(stderr, "error: invalid subject");
return 1;
}
memcpy(newc, oldc, delim - oldc + 1);
newc += delim - oldc + 1;
oldc = delim + 1;
delim = strchr(oldc, '/');
if (!delim) {
delim = arg[1] + strlen(arg[1]);
}
memcpy(newc, oldc, delim - oldc);
newc += delim - oldc;
*newc++ = ',';
oldc = delim + 1;
} while(*delim);
arg++;
}
arg++;
}
gen_key(&key, rsa, ksize, exp, curve, pem);
if (keypath)
write_key(&key, keypath, pem);
from = (from < 1000000000) ? 1000000000 : from;
strftime(fstr, sizeof(fstr), "%Y%m%d%H%M%S", gmtime(&from));
to = from + 60 * 60 * 24 * days;
if (to < from)
to = INT_MAX;
strftime(tstr, sizeof(tstr), "%Y%m%d%H%M%S", gmtime(&to));
fprintf(stderr, "Generating selfsigned certificate with subject '%s'"
" and validity %s-%s\n", subject, fstr, tstr);
mbedtls_x509write_crt_init(&cert);
mbedtls_x509write_crt_set_md_alg(&cert, MBEDTLS_MD_SHA256);
mbedtls_x509write_crt_set_issuer_key(&cert, &key);
mbedtls_x509write_crt_set_subject_key(&cert, &key);
mbedtls_x509write_crt_set_subject_name(&cert, subject);
mbedtls_x509write_crt_set_issuer_name(&cert, subject);
mbedtls_x509write_crt_set_validity(&cert, fstr, tstr);
mbedtls_x509write_crt_set_basic_constraints(&cert, 0, -1);
mbedtls_x509write_crt_set_subject_key_identifier(&cert);
mbedtls_x509write_crt_set_authority_key_identifier(&cert);
_urandom(NULL, (void *) buf, 8);
for (len = 0; len < 8; len++)
sprintf(sstr + len*2, "%02x", (unsigned char) buf[len]);
mbedtls_mpi_init(&serial);
mbedtls_mpi_read_string(&serial, 16, sstr);
mbedtls_x509write_crt_set_serial(&cert, &serial);
if (pem) {
if (mbedtls_x509write_crt_pem(&cert, (void *) buf, sizeof(buf), _urandom, NULL) < 0) {
fprintf(stderr, "Failed to generate certificate\n");
return 1;
}
len = strlen(buf);
} else {
len = mbedtls_x509write_crt_der(&cert, (void *) buf, sizeof(buf), _urandom, NULL);
if (len < 0) {
fprintf(stderr, "Failed to generate certificate: %d\n", len);
return 1;
}
}
write_file(certpath, len, pem);
mbedtls_x509write_crt_free(&cert);
mbedtls_mpi_free(&serial);
mbedtls_pk_free(&key);
return 0;
}
int main(int argc, char *argv[])
{
urandom_fd = open("/dev/urandom", O_RDONLY);
if (!argv[1]) {
//Usage
} else if (!strcmp(argv[1], "eckey")) {
return dokey(false, argv+2);
} else if (!strcmp(argv[1], "rsakey")) {
return dokey(true, argv+2);
} else if (!strcmp(argv[1], "selfsigned")) {
return selfsigned(argv+2);
}
fprintf(stderr,
"PX5G X.509 Certificate Generator Utility v" PX5G_VERSION "\n" PX5G_COPY
"\nbased on PolarSSL by Christophe Devine and Paul Bakker\n\n");
fprintf(stderr, "Usage: %s [eckey|rsakey|selfsigned]\n", *argv);
return 1;
}