s1-mod/deps/libtomcrypt/src/pk/rsa/rsa_import.c
2024-02-27 03:09:30 -05:00

144 lines
4.3 KiB
C

/* LibTomCrypt, modular cryptographic library -- Tom St Denis */
/* SPDX-License-Identifier: Unlicense */
#include "tomcrypt_private.h"
/**
@file rsa_import.c
Import a PKCS RSA key, Tom St Denis
*/
#ifdef LTC_MRSA
/**
Import an RSAPublicKey or RSAPrivateKey as defined in PKCS #1 v2.1 [two-prime only]
The `key` passed into this function has to be already initialized and will
NOT be free'd on error!
@param in The packet to import from
@param inlen It's length (octets)
@param key [out] Destination for newly imported key
@return CRYPT_OK if successful
*/
int rsa_import_pkcs1(const unsigned char *in, unsigned long inlen, rsa_key *key)
{
int err;
unsigned long version = -1;
err = der_decode_sequence_multi(in, inlen, LTC_ASN1_SHORT_INTEGER, 1UL, &version,
LTC_ASN1_EOL, 0UL, NULL);
if (err == CRYPT_OVERFLOW) {
/* the version would fit into an LTC_ASN1_SHORT_INTEGER
* so we try to decode as a public key
*/
if ((err = der_decode_sequence_multi(in, inlen,
LTC_ASN1_INTEGER, 1UL, key->N,
LTC_ASN1_INTEGER, 1UL, key->e,
LTC_ASN1_EOL, 0UL, NULL)) == CRYPT_OK) {
key->type = PK_PUBLIC;
}
goto LBL_OUT;
} else if (err != CRYPT_INPUT_TOO_LONG) {
/* couldn't decode the version, so error out */
goto LBL_OUT;
}
if (version == 0) {
/* it's a private key */
if ((err = der_decode_sequence_multi(in, inlen,
LTC_ASN1_SHORT_INTEGER, 1UL, &version,
LTC_ASN1_INTEGER, 1UL, key->N,
LTC_ASN1_INTEGER, 1UL, key->e,
LTC_ASN1_INTEGER, 1UL, key->d,
LTC_ASN1_INTEGER, 1UL, key->p,
LTC_ASN1_INTEGER, 1UL, key->q,
LTC_ASN1_INTEGER, 1UL, key->dP,
LTC_ASN1_INTEGER, 1UL, key->dQ,
LTC_ASN1_INTEGER, 1UL, key->qP,
LTC_ASN1_EOL, 0UL, NULL)) != CRYPT_OK) {
goto LBL_OUT;
}
key->type = PK_PRIVATE;
} else if (version == 1) {
/* we don't support multi-prime RSA */
err = CRYPT_PK_INVALID_TYPE;
goto LBL_OUT;
}
err = CRYPT_OK;
LBL_OUT:
return err;
}
/**
Import multiple formats of RSA public and private keys.
RSAPublicKey or RSAPrivateKey as defined in PKCS #1 v2.1 [two-prime only]
SubjectPublicKeyInfo formatted public keys
@param in The packet to import from
@param inlen It's length (octets)
@param key [out] Destination for newly imported key
@return CRYPT_OK if successful, upon error allocated memory is freed
*/
int rsa_import(const unsigned char *in, unsigned long inlen, rsa_key *key)
{
int err;
unsigned char *tmpbuf=NULL;
unsigned long tmpbuf_len, len;
LTC_ARGCHK(in != NULL);
LTC_ARGCHK(key != NULL);
LTC_ARGCHK(ltc_mp.name != NULL);
/* init key */
if ((err = rsa_init(key)) != CRYPT_OK) {
return err;
}
/* see if the OpenSSL DER format RSA public key will work */
tmpbuf_len = inlen;
tmpbuf = XCALLOC(1, tmpbuf_len);
if (tmpbuf == NULL) {
err = CRYPT_MEM;
goto LBL_ERR;
}
len = 0;
err = x509_decode_subject_public_key_info(in, inlen,
LTC_OID_RSA, tmpbuf, &tmpbuf_len,
LTC_ASN1_NULL, NULL, &len);
if (err == CRYPT_OK) { /* SubjectPublicKeyInfo format */
/* now it should be SEQUENCE { INTEGER, INTEGER } */
if ((err = der_decode_sequence_multi(tmpbuf, tmpbuf_len,
LTC_ASN1_INTEGER, 1UL, key->N,
LTC_ASN1_INTEGER, 1UL, key->e,
LTC_ASN1_EOL, 0UL, NULL)) != CRYPT_OK) {
goto LBL_ERR;
}
key->type = PK_PUBLIC;
err = CRYPT_OK;
goto LBL_FREE;
}
/* not SSL public key, try to match against PKCS #1 standards */
if ((err = rsa_import_pkcs1(in, inlen, key)) == CRYPT_OK) {
goto LBL_FREE;
}
LBL_ERR:
rsa_free(key);
LBL_FREE:
if (tmpbuf != NULL) {
XFREE(tmpbuf);
}
return err;
}
#endif /* LTC_MRSA */