Source code
Revision control
Copy as Markdown
Other Tools
/*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "defaults.h"
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <botan/ffi.h>
#include <botan/build.h>
#include "utils.h"
#include "repgp/repgp_def.h"
#include "symmetric.h"
static const char *
pgp_sa_to_botan_string(int alg, bool silent = false)
{
switch (alg) {
#if defined(BOTAN_HAS_IDEA) && defined(ENABLE_IDEA)
case PGP_SA_IDEA:
return "IDEA";
#endif
#if defined(BOTAN_HAS_DES)
case PGP_SA_TRIPLEDES:
return "TripleDES";
#endif
#if defined(BOTAN_HAS_CAST) && defined(ENABLE_CAST5)
case PGP_SA_CAST5:
return "CAST-128";
#endif
#if defined(BOTAN_HAS_BLOWFISH) && defined(ENABLE_BLOWFISH)
case PGP_SA_BLOWFISH:
return "Blowfish";
#endif
#if defined(BOTAN_HAS_AES)
case PGP_SA_AES_128:
return "AES-128";
case PGP_SA_AES_192:
return "AES-192";
case PGP_SA_AES_256:
return "AES-256";
#endif
#if defined(BOTAN_HAS_SM4) && defined(ENABLE_SM2)
case PGP_SA_SM4:
return "SM4";
#endif
#if defined(BOTAN_HAS_TWOFISH) && defined(ENABLE_TWOFISH)
case PGP_SA_TWOFISH:
return "Twofish";
#endif
#if defined(BOTAN_HAS_CAMELLIA)
case PGP_SA_CAMELLIA_128:
return "Camellia-128";
case PGP_SA_CAMELLIA_192:
return "Camellia-192";
case PGP_SA_CAMELLIA_256:
return "Camellia-256";
#endif
default:
if (!silent) {
RNP_LOG("Unsupported symmetric algorithm %d", alg);
}
return NULL;
}
}
#if defined(ENABLE_AEAD)
static bool
pgp_aead_to_botan_string(pgp_symm_alg_t ealg, pgp_aead_alg_t aalg, char *buf, size_t len)
{
const char *ealg_name = pgp_sa_to_botan_string(ealg);
size_t ealg_len;
if (!ealg_name) {
return false;
}
ealg_len = strlen(ealg_name);
if (len < ealg_len + 5) {
RNP_LOG("buffer too small");
return false;
}
switch (aalg) {
case PGP_AEAD_EAX:
memcpy(buf, ealg_name, ealg_len);
strncpy(buf + ealg_len, "/EAX", len - ealg_len);
break;
case PGP_AEAD_OCB:
memcpy(buf, ealg_name, ealg_len);
strncpy(buf + ealg_len, "/OCB", len - ealg_len);
break;
default:
RNP_LOG("unsupported AEAD alg %d", (int) aalg);
return false;
}
return true;
}
#endif
bool
pgp_cipher_cfb_start(pgp_crypt_t * crypt,
pgp_symm_alg_t alg,
const uint8_t *key,
const uint8_t *iv)
{
memset(crypt, 0x0, sizeof(*crypt));
const char *cipher_name = pgp_sa_to_botan_string(alg);
if (!cipher_name) {
return false;
}
crypt->alg = alg;
crypt->blocksize = pgp_block_size(alg);
// This shouldn't happen if pgp_sa_to_botan_string returned a ptr
if (botan_block_cipher_init(&(crypt->cfb.obj), cipher_name) != 0) {
RNP_LOG("Block cipher '%s' not available", cipher_name);
return false;
}
const size_t keysize = pgp_key_size(alg);
if (botan_block_cipher_set_key(crypt->cfb.obj, key, keysize) != 0) {
RNP_LOG("Failure setting key on block cipher object");
return false;
}
if (iv != NULL) {
// Otherwise left as all zeros via memset at start of function
memcpy(crypt->cfb.iv, iv, crypt->blocksize);
}
crypt->cfb.remaining = 0;
return true;
}
int
pgp_cipher_cfb_finish(pgp_crypt_t *crypt)
{
if (!crypt) {
return 0;
}
if (crypt->cfb.obj) {
botan_block_cipher_destroy(crypt->cfb.obj);
crypt->cfb.obj = NULL;
}
botan_scrub_mem((uint8_t *) crypt, sizeof(*crypt));
return 0;
}
int
pgp_cipher_encrypt_block(pgp_crypt_t *crypt, uint8_t *iv, size_t blsize)
{
return botan_block_cipher_encrypt_blocks(crypt->cfb.obj, iv, iv, 1);
}
bool
pgp_is_sa_supported(int alg, bool silent)
{
return pgp_sa_to_botan_string(alg, silent);
}
#if defined(ENABLE_AEAD)
bool
pgp_cipher_aead_init(pgp_crypt_t * crypt,
pgp_symm_alg_t ealg,
pgp_aead_alg_t aalg,
const uint8_t *key,
bool decrypt)
{
char cipher_name[32];
uint32_t flags;
memset(crypt, 0x0, sizeof(*crypt));
if (!pgp_aead_to_botan_string(ealg, aalg, cipher_name, sizeof(cipher_name))) {
return false;
}
crypt->alg = ealg;
crypt->blocksize = pgp_block_size(ealg);
crypt->aead.alg = aalg;
crypt->aead.decrypt = decrypt;
crypt->aead.taglen = PGP_AEAD_EAX_OCB_TAG_LEN; /* it's the same for EAX and OCB */
flags = decrypt ? BOTAN_CIPHER_INIT_FLAG_DECRYPT : BOTAN_CIPHER_INIT_FLAG_ENCRYPT;
if (botan_cipher_init(&(crypt->aead.obj), cipher_name, flags)) {
RNP_LOG("cipher %s is not available", cipher_name);
return false;
}
if (botan_cipher_set_key(crypt->aead.obj, key, (size_t) pgp_key_size(ealg))) {
RNP_LOG("failed to set key");
return false;
}
if (botan_cipher_get_update_granularity(crypt->aead.obj, &crypt->aead.granularity)) {
RNP_LOG("failed to get update granularity");
return false;
}
return true;
}
bool
pgp_cipher_aead_set_ad(pgp_crypt_t *crypt, const uint8_t *ad, size_t len)
{
return botan_cipher_set_associated_data(crypt->aead.obj, ad, len) == 0;
}
bool
pgp_cipher_aead_start(pgp_crypt_t *crypt, const uint8_t *nonce, size_t len)
{
return botan_cipher_start(crypt->aead.obj, nonce, len) == 0;
}
bool
pgp_cipher_aead_update(
pgp_crypt_t &crypt, uint8_t *out, const uint8_t *in, size_t len, size_t &read)
{
if (len % crypt.aead.granularity) {
RNP_LOG("aead wrong update len");
return false;
}
size_t outwr = 0;
size_t inread = 0;
if (botan_cipher_update(crypt.aead.obj, 0, out, len, &outwr, in, len, &inread)) {
RNP_LOG("aead update failed");
return false;
}
if (outwr != inread) {
RNP_LOG("wrong aead usage: %zu vs %zu, len is %zu", outwr, inread, len);
return false;
}
read = inread;
return true;
}
void
pgp_cipher_aead_reset(pgp_crypt_t *crypt)
{
botan_cipher_reset(crypt->aead.obj);
}
bool
pgp_cipher_aead_finish(pgp_crypt_t *crypt, uint8_t *out, const uint8_t *in, size_t len)
{
uint32_t flags = BOTAN_CIPHER_UPDATE_FLAG_FINAL;
size_t inread = 0;
size_t outwr = 0;
int res;
if (crypt->aead.decrypt) {
size_t datalen = len - crypt->aead.taglen;
/* for decryption we should have tag for the final update call */
res =
botan_cipher_update(crypt->aead.obj, flags, out, datalen, &outwr, in, len, &inread);
if (res != 0) {
if (res != BOTAN_FFI_ERROR_BAD_MAC) {
RNP_LOG("aead finish failed: %d", res);
}
return false;
}
if ((outwr != datalen) || (inread != len)) {
RNP_LOG("wrong decrypt aead finish usage");
return false;
}
} else {
/* for encryption tag will be generated */
size_t outlen = len + crypt->aead.taglen;
if (botan_cipher_update(
crypt->aead.obj, flags, out, outlen, &outwr, in, len, &inread) != 0) {
RNP_LOG("aead finish failed");
return false;
}
if ((outwr != outlen) || (inread != len)) {
RNP_LOG("wrong encrypt aead finish usage");
return false;
}
}
pgp_cipher_aead_reset(crypt);
return true;
}
void
pgp_cipher_aead_destroy(pgp_crypt_t *crypt)
{
if (crypt->aead.obj) {
botan_cipher_destroy(crypt->aead.obj);
}
memset(crypt, 0x0, sizeof(*crypt));
}
#endif // ENABLE_AEAD