Files
data-lite-c/Sources/DataLiteC/libtomcrypt/misc/pem/pem_pkcs.c
2025-10-24 19:33:21 +03:00

299 lines
8.5 KiB
C

/* LibTomCrypt, modular cryptographic library -- Tom St Denis */
/* SPDX-License-Identifier: Unlicense */
#include "tomcrypt_private.h"
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wconversion"
#pragma clang diagnostic ignored "-Wshorten-64-to-32"
/**
@file pem_decode.c
Decode a PEM file, Steffen Jaeckel
*/
#ifdef LTC_PEM
extern const struct pem_header_id pem_std_headers[];
extern const unsigned long pem_std_headers_num;
static int s_decrypt_pem(unsigned char *asn1_cert, unsigned long *asn1_len, const struct pem_headers *hdr)
{
unsigned char iv[MAXBLOCKSIZE], key[MAXBLOCKSIZE];
unsigned long ivlen, klen;
int err;
if (hdr->info.keylen > sizeof(key)) {
return CRYPT_BUFFER_OVERFLOW;
}
if (!hdr->pw->pw) {
return CRYPT_INVALID_ARG;
}
ivlen = sizeof(iv);
if ((err = base16_decode(hdr->info.iv, XSTRLEN(hdr->info.iv), iv, &ivlen)) != CRYPT_OK) {
return err;
}
klen = hdr->info.keylen;
if ((err = pkcs_5_alg1_openssl(hdr->pw->pw, hdr->pw->l, iv, 1, find_hash("md5"), key, &klen))) {
return err;
}
err = pem_decrypt(asn1_cert, asn1_len, key, klen, iv, ivlen, NULL, 0, &hdr->info, LTC_PAD_PKCS7);
zeromem(key, sizeof(key));
zeromem(iv, sizeof(iv));
return err;
}
static int s_get_pka(ltc_asn1_list *pub, enum ltc_pka_id *pka)
{
der_flexi_check flexi_should[4];
ltc_asn1_list *seqid, *id;
enum ltc_oid_id oid_id;
int err;
unsigned long n = 0;
LTC_SET_DER_FLEXI_CHECK(flexi_should, n++, LTC_ASN1_SEQUENCE, &seqid);
LTC_SET_DER_FLEXI_CHECK(flexi_should, n++, LTC_ASN1_BIT_STRING, NULL);
LTC_SET_DER_FLEXI_CHECK(flexi_should, n, LTC_ASN1_EOL, NULL);
if ((err = der_flexi_sequence_cmp(pub, flexi_should)) != CRYPT_OK) {
return err;
}
n = 0;
LTC_SET_DER_FLEXI_CHECK(flexi_should, n++, LTC_ASN1_OBJECT_IDENTIFIER, &id);
LTC_SET_DER_FLEXI_CHECK(flexi_should, n, LTC_ASN1_EOL, NULL);
err = der_flexi_sequence_cmp(seqid, flexi_should);
if (err != CRYPT_OK && err != CRYPT_INPUT_TOO_LONG) {
return err;
}
if ((err = pk_get_oid_from_asn1(id, &oid_id)) != CRYPT_OK) {
return err;
}
return pk_get_pka_id(oid_id, pka);
}
typedef int (*import_fn)(const unsigned char *, unsigned long, void*);
static const import_fn s_import_x509_fns[LTC_PKA_NUM] = {
#ifdef LTC_MRSA
[LTC_PKA_RSA] = (import_fn)rsa_import_x509,
#endif
#ifdef LTC_MECC
[LTC_PKA_EC] = (import_fn)ecc_import_x509,
#endif
#ifdef LTC_CURVE25519
[LTC_PKA_X25519] = (import_fn)x25519_import_x509,
[LTC_PKA_ED25519] = (import_fn)ed25519_import_x509,
#endif
};
static int s_import_x509(unsigned char *asn1_cert, unsigned long asn1_len, ltc_pka_key *k)
{
enum ltc_pka_id pka = LTC_PKA_UNDEF;
ltc_asn1_list *d, *spki;
int err;
if ((err = x509_decode_spki(asn1_cert, asn1_len, &d, &spki)) != CRYPT_OK) {
return err;
}
err = s_get_pka(spki, &pka);
der_free_sequence_flexi(d);
if (err != CRYPT_OK) {
return err;
}
if (pka < 0
|| pka > LTC_ARRAY_SIZE(s_import_x509_fns)
|| s_import_x509_fns[pka] == NULL) {
return CRYPT_PK_INVALID_TYPE;
}
if ((err = s_import_x509_fns[pka](asn1_cert, asn1_len, &k->u)) == CRYPT_OK) {
k->id = pka;
}
return err;
}
static int s_import_pkcs8(unsigned char *asn1_cert, unsigned long asn1_len, ltc_pka_key *k, const password_ctx *pw_ctx)
{
int err;
enum ltc_oid_id pka;
ltc_asn1_list *alg_id, *priv_key;
ltc_asn1_list *p8_asn1 = NULL;
if ((err = pkcs8_decode_flexi(asn1_cert, asn1_len, pw_ctx, &p8_asn1)) != CRYPT_OK) {
goto cleanup;
}
if ((err = pkcs8_get_children(p8_asn1, &pka, &alg_id, &priv_key)) != CRYPT_OK) {
goto cleanup;
}
switch (pka) {
#ifdef LTC_MDH
case LTC_OID_DH:
err = dh_import_pkcs8_asn1(alg_id, priv_key, &k->u.dh);
k->id = LTC_PKA_DH;
break;
#endif
#ifdef LTC_MDSA
case LTC_OID_DSA:
err = dsa_import_pkcs8_asn1(alg_id, priv_key, &k->u.dsa);
k->id = LTC_PKA_DSA;
break;
#endif
#ifdef LTC_MRSA
case LTC_OID_RSA:
err = rsa_import_pkcs8_asn1(alg_id, priv_key, &k->u.rsa);
k->id = LTC_PKA_RSA;
break;
#endif
#ifdef LTC_MECC
case LTC_OID_EC:
err = ecc_import_pkcs8_asn1(alg_id, priv_key, &k->u.ecc);
k->id = LTC_PKA_EC;
break;
#endif
#ifdef LTC_CURVE25519
case LTC_OID_X25519:
err = x25519_import_pkcs8_asn1(alg_id, priv_key, &k->u.x25519);
k->id = LTC_PKA_X25519;
break;
case LTC_OID_ED25519:
err = ed25519_import_pkcs8_asn1(alg_id, priv_key, &k->u.ed25519);
k->id = LTC_PKA_ED25519;
break;
#endif
default:
err = CRYPT_PK_INVALID_TYPE;
}
cleanup:
if (p8_asn1) {
der_sequence_free(p8_asn1);
}
return err;
}
static int s_extract_pka(unsigned char *asn1_cert, unsigned long asn1_len, enum ltc_pka_id *pka)
{
ltc_asn1_list *pub;
int err = CRYPT_ERROR;
if ((err = der_decode_sequence_flexi(asn1_cert, &asn1_len, &pub)) != CRYPT_OK) {
return err;
}
err = s_get_pka(pub, pka);
der_sequence_free(pub);
return err;
}
static const import_fn s_import_openssl_fns[LTC_PKA_NUM] = {
#ifdef LTC_MRSA
[LTC_PKA_RSA] = (import_fn)rsa_import,
#endif
#ifdef LTC_MDSA
[LTC_PKA_DSA] = (import_fn)dsa_import,
#endif
#ifdef LTC_MECC
[LTC_PKA_EC] = (import_fn)ecc_import_openssl,
#endif
#ifdef LTC_CURVE25519
[LTC_PKA_X25519] = (import_fn)x25519_import,
[LTC_PKA_ED25519] = (import_fn)ed25519_import,
#endif
};
static int s_decode(struct get_char *g, ltc_pka_key *k, const password_ctx *pw_ctx)
{
unsigned char *asn1_cert = NULL;
unsigned long w, asn1_len, n;
int err = CRYPT_ERROR;
struct pem_headers hdr = { 0 };
struct password pw = { 0 };
enum ltc_pka_id pka;
XMEMSET(k, 0, sizeof(*k));
w = LTC_PEM_READ_BUFSIZE * 2;
retry:
asn1_cert = XREALLOC(asn1_cert, w);
for (n = 0; n < pem_std_headers_num; ++n) {
hdr.id = &pem_std_headers[n];
err = pem_read(asn1_cert, &w, &hdr, g);
if (err == CRYPT_BUFFER_OVERFLOW) {
goto retry;
} else if (err == CRYPT_OK) {
break;
} else if (err != CRYPT_UNKNOWN_PEM) {
goto cleanup;
}
hdr.id = NULL;
}
/* id not found */
if (hdr.id == NULL)
goto cleanup;
asn1_len = w;
if (hdr.id->flags & pf_pkcs8) {
err = s_import_pkcs8(asn1_cert, asn1_len, k, pw_ctx);
goto cleanup;
} else if (hdr.id->flags == pf_x509) {
err = s_import_x509(asn1_cert, asn1_len, k);
goto cleanup;
} else if ((hdr.id->flags & pf_public) && hdr.id->pka == LTC_PKA_UNDEF) {
if ((err = s_extract_pka(asn1_cert, asn1_len, &pka)) != CRYPT_OK) {
goto cleanup;
}
} else if (hdr.encrypted) {
if ((pw_ctx == NULL) || (pw_ctx->callback == NULL)) {
err = CRYPT_PW_CTX_MISSING;
goto cleanup;
}
hdr.pw = &pw;
if (pw_ctx->callback(&hdr.pw->pw, &hdr.pw->l, pw_ctx->userdata)) {
err = CRYPT_ERROR;
goto cleanup;
}
if ((err = s_decrypt_pem(asn1_cert, &asn1_len, &hdr)) != CRYPT_OK) {
goto cleanup;
}
pka = hdr.id->pka;
} else {
pka = hdr.id->pka;
}
if (pka < 0
|| pka > LTC_ARRAY_SIZE(s_import_openssl_fns)
|| s_import_openssl_fns[pka] == NULL) {
err = CRYPT_PK_INVALID_TYPE;
goto cleanup;
}
if ((err = s_import_openssl_fns[pka](asn1_cert, asn1_len, &k->u)) == CRYPT_OK) {
k->id = pka;
}
cleanup:
password_free(hdr.pw, pw_ctx);
XFREE(asn1_cert);
return err;
}
#ifndef LTC_NO_FILE
int pem_decode_pkcs_filehandle(FILE *f, ltc_pka_key *k, const password_ctx *pw_ctx)
{
LTC_ARGCHK(f != NULL);
LTC_ARGCHK(k != NULL);
{
struct get_char g = { .get = pem_get_char_from_file, .data.f = f };
return s_decode(&g, k, pw_ctx);
}
}
#endif /* LTC_NO_FILE */
int pem_decode_pkcs(const void *buf, unsigned long len, ltc_pka_key *k, const password_ctx *pw_ctx)
{
LTC_ARGCHK(buf != NULL);
LTC_ARGCHK(len != 0);
LTC_ARGCHK(k != NULL);
{
struct get_char g = { .get = pem_get_char_from_buf, SET_BUFP(.data.buf, buf, len) };
return s_decode(&g, k, pw_ctx);
}
}
#endif /* LTC_PEM */
#pragma clang diagnostic pop