Added support code for RSA and EC key encoding (including reconstruction of all public and private key elements from the private key structure), with raw and PKCS#8 formats, both in DER and PEM.

This commit is contained in:
Thomas Pornin 2018-08-06 00:02:36 +02:00
parent cfbc702d3d
commit d8fa415fca
32 changed files with 3528 additions and 105 deletions

View file

@ -298,11 +298,22 @@ int uses_ecdhe(unsigned suite);
*/
void list_names(void);
/*
* Print out all known elliptic curve names.
*/
void list_curves(void);
/*
* Get the symbolic name for an elliptic curve (by ID).
*/
const char *ec_curve_name(int curve);
/*
* Get a curve by symbolic name. If the name is not recognized, -1 is
* returned.
*/
int get_curve_by_name(const char *str);
/*
* Get the symbolic name for a hash function name (by ID).
*/

View file

@ -322,68 +322,99 @@ const cipher_suite cipher_suites[] = {
static const struct {
int id;
const char *name;
const char *sid[4];
} curves[] = {
{ BR_EC_sect163k1,
"sect163k1" },
"sect163k1",
{ "sect163k1", "K-163", NULL, NULL } },
{ BR_EC_sect163r1,
"sect163r1" },
"sect163r1",
{ "sect163r1", NULL, NULL, NULL } },
{ BR_EC_sect163r2,
"sect163r2" },
"sect163r2",
{ "sect163r2", "B-163", NULL, NULL } },
{ BR_EC_sect193r1,
"sect193r1" },
"sect193r1",
{ "sect193r1", NULL, NULL, NULL } },
{ BR_EC_sect193r2,
"sect193r2" },
"sect193r2",
{ "sect193r2", NULL, NULL, NULL } },
{ BR_EC_sect233k1,
"sect233k1" },
"sect233k1",
{ "sect233k1", "K-233", NULL, NULL } },
{ BR_EC_sect233r1,
"sect233r1" },
"sect233r1",
{ "sect233r1", "B-233", NULL, NULL } },
{ BR_EC_sect239k1,
"sect239k1" },
"sect239k1",
{ "sect239k1", NULL, NULL, NULL } },
{ BR_EC_sect283k1,
"sect283k1" },
"sect283k1",
{ "sect283k1", "K-283", NULL, NULL } },
{ BR_EC_sect283r1,
"sect283r1" },
"sect283r1",
{ "sect283r1", "B-283", NULL, NULL } },
{ BR_EC_sect409k1,
"sect409k1" },
"sect409k1",
{ "sect409k1", "K-409", NULL, NULL } },
{ BR_EC_sect409r1,
"sect409r1" },
"sect409r1",
{ "sect409r1", "B-409", NULL, NULL } },
{ BR_EC_sect571k1,
"sect571k1" },
"sect571k1",
{ "sect571k1", "K-571", NULL, NULL } },
{ BR_EC_sect571r1,
"sect571r1" },
"sect571r1",
{ "sect571r1", "B-571", NULL, NULL } },
{ BR_EC_secp160k1,
"secp160k1" },
"secp160k1",
{ "secp160k1", NULL, NULL, NULL } },
{ BR_EC_secp160r1,
"secp160r1" },
"secp160r1",
{ "secp160r1", NULL, NULL, NULL } },
{ BR_EC_secp160r2,
"secp160r2" },
"secp160r2",
{ "secp160r2", NULL, NULL, NULL } },
{ BR_EC_secp192k1,
"secp192k1" },
"secp192k1",
{ "secp192k1", NULL, NULL, NULL } },
{ BR_EC_secp192r1,
"secp192r1" },
"secp192r1",
{ "secp192r1", "P-192", NULL, NULL } },
{ BR_EC_secp224k1,
"secp224k1" },
"secp224k1",
{ "secp224k1", NULL, NULL, NULL } },
{ BR_EC_secp224r1,
"secp224r1" },
"secp224r1",
{ "secp224r1", "P-224", NULL, NULL } },
{ BR_EC_secp256k1,
"secp256k1" },
"secp256k1",
{ "secp256k1", NULL, NULL, NULL } },
{ BR_EC_secp256r1,
"secp256r1 (P-256)" },
"secp256r1 (P-256)",
{ "secp256r1", "P-256", "prime256v1", NULL } },
{ BR_EC_secp384r1,
"secp384r1 (P-384)" },
"secp384r1 (P-384)",
{ "secp384r1", "P-384", NULL, NULL } },
{ BR_EC_secp521r1,
"secp521r1 (P-521)" },
"secp521r1 (P-521)",
{ "secp521r1", "P-521", NULL, NULL } },
{ BR_EC_brainpoolP256r1,
"brainpoolP256r1" },
"brainpoolP256r1",
{ "brainpoolP256r1", NULL, NULL, NULL } },
{ BR_EC_brainpoolP384r1,
"brainpoolP384r1" },
"brainpoolP384r1",
{ "brainpoolP384r1", NULL, NULL, NULL } },
{ BR_EC_brainpoolP512r1,
"brainpoolP512r1" },
"brainpoolP512r1",
{ "brainpoolP512r1", NULL, NULL, NULL } },
{ BR_EC_curve25519,
"Curve25519" },
"Curve25519",
{ "curve25519", "c25519", NULL, NULL } },
{ BR_EC_curve448,
"Curve448" },
{ 0, 0 }
"Curve448",
{ "curve448", "c448", NULL, NULL } },
{ 0, 0, { 0, 0, 0, 0 } }
};
static const struct {
@ -627,6 +658,31 @@ list_names(void)
}
}
/* see brssl.h */
void
list_curves(void)
{
size_t u;
for (u = 0; curves[u].name; u ++) {
size_t v;
for (v = 0; curves[u].sid[v]; v ++) {
if (v == 0) {
printf(" ");
} else if (v == 1) {
printf(" (");
} else {
printf(", ");
}
printf("%s", curves[u].sid[v]);
}
if (v > 1) {
printf(")");
}
printf("\n");
}
}
static int
is_ign(int c)
{
@ -956,6 +1012,22 @@ ec_curve_name(int curve)
}
}
/* see brssl.h */
int
get_curve_by_name(const char *str)
{
size_t u, v;
for (u = 0; curves[u].name; u ++) {
for (v = 0; curves[u].sid[v]; v ++) {
if (eqstr(curves[u].sid[v], str)) {
return curves[u].id;
}
}
}
return -1;
}
/* see brssl.h */
const char *
hash_function_name(int id)

View file

@ -31,6 +31,15 @@
#include "brssl.h"
#include "bearssl.h"
typedef struct {
int print_text;
int print_C;
const char *rawder;
const char *rawpem;
const char *pk8der;
const char *pk8pem;
} outspec;
static void
print_int_text(const char *name, const unsigned char *buf, size_t len)
{
@ -63,17 +72,70 @@ print_int_C(const char *name, const unsigned char *buf, size_t len)
printf("\n};\n");
}
static void
print_rsa(const br_rsa_private_key *sk, int print_text, int print_C)
static int
write_to_file(const char *name, const void *data, size_t len)
{
if (print_text) {
FILE *f;
f = fopen(name, "wb");
if (f == NULL) {
fprintf(stderr,
"ERROR: cannot open file '%s' for writing\n",
name);
return 0;
}
if (fwrite(data, 1, len, f) != len) {
fclose(f);
fprintf(stderr,
"ERROR: cannot write to file '%s'\n",
name);
return 0;
}
fclose(f);
return 1;
}
static int
write_to_pem_file(const char *name,
const void *data, size_t len, const char *banner)
{
void *pem;
size_t pemlen;
int r;
pemlen = br_pem_encode(NULL, NULL, len, banner, 0);
pem = xmalloc(pemlen + 1);
br_pem_encode(pem, data, len, banner, 0);
r = write_to_file(name, pem, pemlen);
xfree(pem);
return r;
}
static int
print_rsa(const br_rsa_private_key *sk, outspec *os)
{
int ret;
unsigned char *n, *d, *buf;
uint32_t e;
size_t nlen, dlen, len;
br_rsa_compute_modulus cm;
br_rsa_compute_pubexp ce;
br_rsa_compute_privexp cd;
br_rsa_public_key pk;
unsigned char ebuf[4];
n = NULL;
d = NULL;
buf = NULL;
ret = 1;
if (os->print_text) {
print_int_text("p ", sk->p, sk->plen);
print_int_text("q ", sk->q, sk->qlen);
print_int_text("dp", sk->dp, sk->dplen);
print_int_text("dq", sk->dq, sk->dqlen);
print_int_text("iq", sk->iq, sk->iqlen);
}
if (print_C) {
if (os->print_C) {
print_int_C("RSA_P", sk->p, sk->plen);
print_int_C("RSA_Q", sk->q, sk->qlen);
print_int_C("RSA_DP", sk->dp, sk->dplen);
@ -88,21 +150,174 @@ print_rsa(const br_rsa_private_key *sk, int print_text, int print_C)
printf("\t(unsigned char *)RSA_IQ, sizeof RSA_IQ\n");
printf("};\n");
}
if (os->rawder == NULL && os->rawpem == NULL
&& os->pk8der == NULL && os->pk8pem == NULL)
{
return ret;
}
cm = br_rsa_compute_modulus_get_default();
ce = br_rsa_compute_pubexp_get_default();
cd = br_rsa_compute_privexp_get_default();
nlen = cm(NULL, sk);
if (nlen == 0) {
goto print_RSA_error;
}
n = xmalloc(nlen);
if (cm(n, sk) != nlen) {
goto print_RSA_error;
}
e = ce(sk);
if (e == 0) {
goto print_RSA_error;
}
dlen = cd(NULL, sk, e);
if (dlen == 0) {
goto print_RSA_error;
}
d = xmalloc(dlen);
if (cd(d, sk, e) != dlen) {
goto print_RSA_error;
}
ebuf[0] = e >> 24;
ebuf[1] = e >> 16;
ebuf[2] = e >> 8;
ebuf[3] = e;
pk.n = n;
pk.nlen = nlen;
pk.e = ebuf;
pk.elen = sizeof ebuf;
if (os->rawder != NULL || os->rawpem != NULL) {
len = br_encode_rsa_raw_der(NULL, sk, &pk, d, dlen);
if (len == 0) {
goto print_RSA_error;
}
buf = xmalloc(len);
if (br_encode_rsa_raw_der(buf, sk, &pk, d, dlen) != len) {
goto print_RSA_error;
}
if (os->rawder != NULL) {
ret &= write_to_file(os->rawder, buf, len);
}
if (os->rawpem != NULL) {
ret &= write_to_pem_file(os->rawpem,
buf, len, "RSA PRIVATE KEY");
}
xfree(buf);
buf = NULL;
}
if (os->pk8der != NULL || os->pk8pem != NULL) {
len = br_encode_rsa_pkcs8_der(NULL, sk, &pk, d, dlen);
if (len == 0) {
goto print_RSA_error;
}
buf = xmalloc(len);
if (br_encode_rsa_pkcs8_der(buf, sk, &pk, d, dlen) != len) {
goto print_RSA_error;
}
if (os->pk8der != NULL) {
ret &= write_to_file(os->pk8der, buf, len);
}
if (os->pk8pem != NULL) {
ret &= write_to_pem_file(os->pk8pem,
buf, len, "PRIVATE KEY");
}
xfree(buf);
buf = NULL;
}
print_RSA_exit:
xfree(n);
xfree(d);
xfree(buf);
return ret;
print_RSA_error:
fprintf(stderr, "ERROR: cannot encode RSA key\n");
ret = 0;
goto print_RSA_exit;
}
static void
print_ec(const br_ec_private_key *sk, int print_text, int print_C)
static int
print_ec(const br_ec_private_key *sk, outspec *os)
{
if (print_text) {
br_ec_public_key pk;
unsigned kbuf[BR_EC_KBUF_PUB_MAX_SIZE];
unsigned char *buf;
size_t len;
int r;
if (os->print_text) {
print_int_text("x", sk->x, sk->xlen);
}
if (print_C) {
if (os->print_C) {
print_int_C("EC_X", sk->x, sk->xlen);
printf("\nstatic const br_ec_private_key EC = {\n");
printf("\t%d,\n", sk->curve);
printf("\t(unsigned char *)EC_X, sizeof EC_X\n");
printf("};\n");
}
if (os->rawder == NULL && os->rawpem == NULL
&& os->pk8der == NULL && os->pk8pem == NULL)
{
return 1;
}
if (br_ec_compute_pub(br_ec_get_default(), &pk, kbuf, sk) == 0) {
fprintf(stderr,
"ERROR: cannot re-encode (unsupported curve)\n");
return 0;
}
r = 1;
if (os->rawder != NULL || os->rawpem != NULL) {
len = br_encode_ec_raw_der(NULL, sk, &pk);
if (len == 0) {
fprintf(stderr, "ERROR: cannot re-encode"
" (unsupported curve)\n");
return 0;
}
buf = xmalloc(len);
if (br_encode_ec_raw_der(buf, sk, &pk) != len) {
fprintf(stderr, "ERROR: re-encode failure\n");
xfree(buf);
return 0;
}
if (os->rawder != NULL) {
r &= write_to_file(os->rawder, buf, len);
}
if (os->rawpem != NULL) {
r &= write_to_pem_file(os->rawpem,
buf, len, "EC PRIVATE KEY");
}
xfree(buf);
}
if (os->pk8der != NULL || os->pk8pem != NULL) {
len = br_encode_ec_pkcs8_der(NULL, sk, &pk);
if (len == 0) {
fprintf(stderr, "ERROR: cannot re-encode"
" (unsupported curve)\n");
return 0;
}
buf = xmalloc(len);
if (br_encode_ec_pkcs8_der(buf, sk, &pk) != len) {
fprintf(stderr, "ERROR: re-encode failure\n");
xfree(buf);
return 0;
}
if (os->pk8der != NULL) {
r &= write_to_file(os->pk8der, buf, len);
}
if (os->pk8pem != NULL) {
r &= write_to_pem_file(os->pk8pem,
buf, len, "PRIVATE KEY");
}
xfree(buf);
}
return r;
}
static int
@ -158,7 +373,7 @@ parse_rsa_spec(const char *kgen_spec, unsigned *size, uint32_t *pubexp)
}
static int
keygen_rsa(unsigned size, uint32_t pubexp, int print_text, int print_C)
keygen_rsa(unsigned size, uint32_t pubexp, outspec *os)
{
br_hmac_drbg_context rng;
br_prng_seeder seeder;
@ -183,17 +398,72 @@ keygen_rsa(unsigned size, uint32_t pubexp, int print_text, int print_C)
if (!r) {
fprintf(stderr, "ERROR: RSA key pair generation failed\n");
} else {
print_rsa(&sk, print_text, print_C);
r = print_rsa(&sk, os);
}
xfree(kbuf_priv);
return r;
}
static int
decode_key(const unsigned char *buf, size_t len, int print_text, int print_C)
parse_ec_spec(const char *kgen_spec, int *curve)
{
const char *p;
*curve = 0;
p = kgen_spec;
if (*p != 'e' && *p != 'E') {
return 0;
}
p ++;
if (*p != 'c' && *p != 'C') {
return 0;
}
p ++;
if (*p == 0) {
*curve = BR_EC_secp256r1;
return 1;
}
if (*p != ':') {
return 0;
}
*curve = get_curve_by_name(p);
return *curve > 0;
}
static int
keygen_ec(int curve, outspec *os)
{
br_hmac_drbg_context rng;
br_prng_seeder seeder;
const br_ec_impl *impl;
br_ec_private_key sk;
unsigned char kbuf_priv[BR_EC_KBUF_PRIV_MAX_SIZE];
size_t len;
seeder = br_prng_seeder_system(NULL);
if (seeder == 0) {
fprintf(stderr, "ERROR: no system source of randomness\n");
return 0;
}
br_hmac_drbg_init(&rng, &br_sha256_vtable, NULL, 0);
if (!seeder(&rng.vtable)) {
fprintf(stderr, "ERROR: system source of randomness failed\n");
return 0;
}
impl = br_ec_get_default();
len = br_ec_keygen(&rng.vtable, impl, &sk, kbuf_priv, curve);
if (len == 0) {
fprintf(stderr, "ERROR: curve is not supported\n");
return 0;
}
return print_ec(&sk, os);
}
static int
decode_key(const unsigned char *buf, size_t len, outspec *os)
{
br_skey_decoder_context dc;
int err;
int err, ret;
br_skey_decoder_init(&dc);
br_skey_decoder_push(&dc, buf, len);
@ -208,8 +478,9 @@ decode_key(const unsigned char *buf, size_t len, int print_text, int print_C)
} else {
fprintf(stderr, " (unknown)\n");
}
return -1;
return 0;
}
ret = 1;
switch (br_skey_decoder_key_type(&dc)) {
const br_rsa_private_key *rk;
const br_ec_private_key *ek;
@ -217,23 +488,24 @@ decode_key(const unsigned char *buf, size_t len, int print_text, int print_C)
case BR_KEYTYPE_RSA:
rk = br_skey_decoder_get_rsa(&dc);
printf("RSA key (%lu bits)\n", (unsigned long)rk->n_bitlen);
print_rsa(rk, print_text, print_C);
ret = print_rsa(rk, os);
break;
case BR_KEYTYPE_EC:
ek = br_skey_decoder_get_ec(&dc);
printf("EC key (curve = %d: %s)\n",
ek->curve, ec_curve_name(ek->curve));
print_ec(ek, print_text, print_C);
ret = print_ec(ek, os);
break;
default:
fprintf(stderr, "Unknown key type: %d\n",
br_skey_decoder_key_type(&dc));
return -1;
ret = 0;
break;
}
return 0;
return ret;
}
static void
@ -244,19 +516,31 @@ usage_skey(void)
fprintf(stderr,
"options:\n");
fprintf(stderr,
" -q suppress verbose messages\n");
" -q suppress verbose messages\n");
fprintf(stderr,
" -text print public key details (human-readable)\n");
" -text print private key details (human-readable)\n");
fprintf(stderr,
" -C print public key details (C code)\n");
" -C print private key details (C code)\n");
fprintf(stderr,
" -gen spec generate a new key using the provided key specification\n");
" -rawder file save private key in 'file' (raw format, DER)\n");
fprintf(stderr,
" -rawpem file save private key in 'file' (raw format, PEM)\n");
fprintf(stderr,
" -pk8der file save private key in 'file' (PKCS#8 format, DER)\n");
fprintf(stderr,
" -pk8pem file save private key in 'file' (PKCS#8 format, PEM)\n");
fprintf(stderr,
" -gen spec generate a new key using the provided key specification\n");
fprintf(stderr,
" -list list known elliptic curve names\n");
fprintf(stderr,
"Key specification begins with a key type, followed by optional parameters\n");
fprintf(stderr,
"that depend on the key type, separated by colon characters:\n");
fprintf(stderr,
" rsa[:size[:pubexep]] RSA key (defaults: size = 2048, pubexp = 3)\n");
fprintf(stderr,
" ec[:curvename] EC key (default curve: secp256r1)\n");
}
/* see brssl.h */
@ -266,7 +550,7 @@ do_skey(int argc, char *argv[])
int retcode;
int verbose;
int i, num_files;
int print_text, print_C;
outspec os;
unsigned char *buf;
size_t len;
pem_object *pos;
@ -274,8 +558,12 @@ do_skey(int argc, char *argv[])
retcode = 0;
verbose = 1;
print_text = 0;
print_C = 0;
os.print_text = 0;
os.print_C = 0;
os.rawder = NULL;
os.rawpem = NULL;
os.pk8der = NULL;
os.pk8pem = NULL;
num_files = 0;
buf = NULL;
pos = NULL;
@ -294,9 +582,69 @@ do_skey(int argc, char *argv[])
} else if (eqstr(arg, "-q") || eqstr(arg, "-quiet")) {
verbose = 0;
} else if (eqstr(arg, "-text")) {
print_text = 1;
os.print_text = 1;
} else if (eqstr(arg, "-C")) {
print_C = 1;
os.print_C = 1;
} else if (eqstr(arg, "-rawder")) {
if (++ i >= argc) {
fprintf(stderr,
"ERROR: no argument for '-rawder'\n");
usage_skey();
goto skey_exit_error;
}
if (os.rawder != NULL) {
fprintf(stderr,
"ERROR: multiple '-rawder' options\n");
usage_skey();
goto skey_exit_error;
}
os.rawder = argv[i];
argv[i] = NULL;
} else if (eqstr(arg, "-rawpem")) {
if (++ i >= argc) {
fprintf(stderr,
"ERROR: no argument for '-rawpem'\n");
usage_skey();
goto skey_exit_error;
}
if (os.rawpem != NULL) {
fprintf(stderr,
"ERROR: multiple '-rawpem' options\n");
usage_skey();
goto skey_exit_error;
}
os.rawpem = argv[i];
argv[i] = NULL;
} else if (eqstr(arg, "-pk8der")) {
if (++ i >= argc) {
fprintf(stderr,
"ERROR: no argument for '-pk8der'\n");
usage_skey();
goto skey_exit_error;
}
if (os.pk8der != NULL) {
fprintf(stderr,
"ERROR: multiple '-pk8der' options\n");
usage_skey();
goto skey_exit_error;
}
os.pk8der = argv[i];
argv[i] = NULL;
} else if (eqstr(arg, "-pk8pem")) {
if (++ i >= argc) {
fprintf(stderr,
"ERROR: no argument for '-pk8pem'\n");
usage_skey();
goto skey_exit_error;
}
if (os.pk8pem != NULL) {
fprintf(stderr,
"ERROR: multiple '-pk8pem' options\n");
usage_skey();
goto skey_exit_error;
}
os.pk8pem = argv[i];
argv[i] = NULL;
} else if (eqstr(arg, "-gen")) {
if (++ i >= argc) {
fprintf(stderr,
@ -312,6 +660,9 @@ do_skey(int argc, char *argv[])
}
kgen_spec = argv[i];
argv[i] = NULL;
} else if (eqstr(arg, "-list")) {
list_curves();
goto skey_exit;
} else {
fprintf(stderr, "ERROR: unknown option: '%s'\n", arg);
usage_skey();
@ -321,6 +672,7 @@ do_skey(int argc, char *argv[])
if (kgen_spec != NULL) {
unsigned rsa_size;
uint32_t rsa_pubexp;
int curve;
if (num_files != 0) {
fprintf(stderr,
@ -330,7 +682,13 @@ do_skey(int argc, char *argv[])
}
if (parse_rsa_spec(kgen_spec, &rsa_size, &rsa_pubexp)) {
keygen_rsa(rsa_size, rsa_pubexp, print_text, print_C);
if (!keygen_rsa(rsa_size, rsa_pubexp, &os)) {
goto skey_exit_error;
}
} else if (parse_ec_spec(kgen_spec, &curve)) {
if (!keygen_ec(curve, &os)) {
goto skey_exit_error;
}
} else {
fprintf(stderr,
"ERROR: unknown key specification: '%s'\n",
@ -360,7 +718,7 @@ do_skey(int argc, char *argv[])
fprintf(stderr, "File '%s': ASN.1/DER object\n",
fname);
}
if (decode_key(buf, len, print_text, print_C) < 0) {
if (!decode_key(buf, len, &os)) {
goto skey_exit_error;
}
} else {
@ -382,9 +740,8 @@ do_skey(int argc, char *argv[])
|| eqstr(name, "EC PRIVATE KEY")
|| eqstr(name, "PRIVATE KEY"))
{
if (decode_key(pos[u].data,
pos[u].data_len,
print_text, print_C) < 0)
if (!decode_key(pos[u].data,
pos[u].data_len, &os))
{
goto skey_exit_error;
}