Files
libsodium/src/libsodium/crypto_aead/chacha20poly1305/sodium/aead_chacha20poly1305.c
T
2016-04-02 12:08:41 +02:00

360 lines
13 KiB
C

#include <stdint.h>
#include <stdlib.h>
#include <limits.h>
#include <string.h>
#include "crypto_aead_chacha20poly1305.h"
#include "crypto_onetimeauth_poly1305.h"
#include "crypto_stream_chacha20.h"
#include "crypto_verify_16.h"
#include "utils.h"
#include "../../sodium/common.h"
static const unsigned char _pad0[16];
int
crypto_aead_chacha20poly1305_encrypt_detached(unsigned char *c,
unsigned char *mac,
unsigned long long *maclen_p,
const unsigned char *m,
unsigned long long mlen,
const unsigned char *ad,
unsigned long long adlen,
const unsigned char *nsec,
const unsigned char *npub,
const unsigned char *k)
{
crypto_onetimeauth_poly1305_state state;
unsigned char block0[64U];
unsigned char slen[8U];
(void) nsec;
crypto_stream_chacha20(block0, sizeof block0, npub, k);
crypto_onetimeauth_poly1305_init(&state, block0);
sodium_memzero(block0, sizeof block0);
crypto_onetimeauth_poly1305_update(&state, ad, adlen);
STORE64_LE(slen, (uint64_t) adlen);
crypto_onetimeauth_poly1305_update(&state, slen, sizeof slen);
crypto_stream_chacha20_xor_ic(c, m, mlen, npub, 1U, k);
crypto_onetimeauth_poly1305_update(&state, c, mlen);
STORE64_LE(slen, (uint64_t) mlen);
crypto_onetimeauth_poly1305_update(&state, slen, sizeof slen);
crypto_onetimeauth_poly1305_final(&state, mac);
sodium_memzero(&state, sizeof state);
if (maclen_p != NULL) {
*maclen_p = crypto_aead_chacha20poly1305_ABYTES;
}
return 0;
}
int
crypto_aead_chacha20poly1305_encrypt(unsigned char *c,
unsigned long long *clen_p,
const unsigned char *m,
unsigned long long mlen,
const unsigned char *ad,
unsigned long long adlen,
const unsigned char *nsec,
const unsigned char *npub,
const unsigned char *k)
{
unsigned long long clen = 0ULL;
int ret;
if (mlen > UINT64_MAX - crypto_aead_chacha20poly1305_ABYTES) {
abort(); /* LCOV_EXCL_LINE */
}
ret = crypto_aead_chacha20poly1305_encrypt_detached(c,
c + mlen, NULL,
m, mlen,
ad, adlen,
nsec, npub, k);
if (clen_p != NULL) {
if (ret == 0) {
clen = mlen + crypto_aead_chacha20poly1305_ABYTES;
}
*clen_p = clen;
}
return ret;
}
int
crypto_aead_chacha20poly1305_ietf_encrypt_detached(unsigned char *c,
unsigned char *mac,
unsigned long long *maclen_p,
const unsigned char *m,
unsigned long long mlen,
const unsigned char *ad,
unsigned long long adlen,
const unsigned char *nsec,
const unsigned char *npub,
const unsigned char *k)
{
crypto_onetimeauth_poly1305_state state;
unsigned char block0[64U];
unsigned char slen[8U];
(void) nsec;
crypto_stream_chacha20_ietf(block0, sizeof block0, npub, k);
crypto_onetimeauth_poly1305_init(&state, block0);
sodium_memzero(block0, sizeof block0);
crypto_onetimeauth_poly1305_update(&state, ad, adlen);
crypto_onetimeauth_poly1305_update(&state, _pad0, (0x10 - adlen) & 0xf);
crypto_stream_chacha20_ietf_xor_ic(c, m, mlen, npub, 1U, k);
crypto_onetimeauth_poly1305_update(&state, c, mlen);
crypto_onetimeauth_poly1305_update(&state, _pad0, (0x10 - mlen) & 0xf);
STORE64_LE(slen, (uint64_t) adlen);
crypto_onetimeauth_poly1305_update(&state, slen, sizeof slen);
STORE64_LE(slen, (uint64_t) mlen);
crypto_onetimeauth_poly1305_update(&state, slen, sizeof slen);
crypto_onetimeauth_poly1305_final(&state, mac);
sodium_memzero(&state, sizeof state);
if (maclen_p != NULL) {
*maclen_p = crypto_aead_chacha20poly1305_ietf_ABYTES;
}
return 0;
}
int
crypto_aead_chacha20poly1305_ietf_encrypt(unsigned char *c,
unsigned long long *clen_p,
const unsigned char *m,
unsigned long long mlen,
const unsigned char *ad,
unsigned long long adlen,
const unsigned char *nsec,
const unsigned char *npub,
const unsigned char *k)
{
unsigned long long clen = 0ULL;
int ret;
if (mlen > UINT64_MAX - crypto_aead_chacha20poly1305_ietf_ABYTES) {
abort(); /* LCOV_EXCL_LINE */
}
ret = crypto_aead_chacha20poly1305_ietf_encrypt_detached(c,
c + mlen, NULL,
m, mlen,
ad, adlen,
nsec, npub, k);
if (clen_p != NULL) {
if (ret == 0) {
clen = mlen + crypto_aead_chacha20poly1305_ietf_ABYTES;
}
*clen_p = clen;
}
return ret;
}
int
crypto_aead_chacha20poly1305_decrypt_detached(unsigned char *m,
unsigned char *nsec,
const unsigned char *c,
unsigned long long clen,
const unsigned char *mac,
const unsigned char *ad,
unsigned long long adlen,
const unsigned char *npub,
const unsigned char *k)
{
crypto_onetimeauth_poly1305_state state;
unsigned char block0[64U];
unsigned char slen[8U];
unsigned char computed_mac[crypto_aead_chacha20poly1305_ABYTES];
unsigned long long mlen;
int ret;
(void) nsec;
crypto_stream_chacha20(block0, sizeof block0, npub, k);
crypto_onetimeauth_poly1305_init(&state, block0);
sodium_memzero(block0, sizeof block0);
crypto_onetimeauth_poly1305_update(&state, ad, adlen);
STORE64_LE(slen, (uint64_t) adlen);
crypto_onetimeauth_poly1305_update(&state, slen, sizeof slen);
mlen = clen;
crypto_onetimeauth_poly1305_update(&state, c, mlen);
STORE64_LE(slen, (uint64_t) mlen);
crypto_onetimeauth_poly1305_update(&state, slen, sizeof slen);
crypto_onetimeauth_poly1305_final(&state, computed_mac);
sodium_memzero(&state, sizeof state);
(void) sizeof(int[sizeof computed_mac == 16U ? 1 : -1]);
ret = crypto_verify_16(computed_mac, mac);
sodium_memzero(computed_mac, sizeof computed_mac);
if (ret != 0) {
memset(m, 0, mlen);
return -1;
}
crypto_stream_chacha20_xor_ic(m, c, mlen, npub, 1U, k);
return 0;
}
int
crypto_aead_chacha20poly1305_decrypt(unsigned char *m,
unsigned long long *mlen_p,
unsigned char *nsec,
const unsigned char *c,
unsigned long long clen,
const unsigned char *ad,
unsigned long long adlen,
const unsigned char *npub,
const unsigned char *k)
{
unsigned long long mlen = 0ULL;
int ret = -1;
if (clen >= crypto_aead_chacha20poly1305_ABYTES) {
ret = crypto_aead_chacha20poly1305_decrypt_detached
(m, nsec,
c, clen - crypto_aead_chacha20poly1305_ABYTES,
c + clen - crypto_aead_chacha20poly1305_ABYTES,
ad, adlen, npub, k);
}
if (mlen_p != NULL) {
if (ret == 0) {
mlen = clen - crypto_aead_chacha20poly1305_ABYTES;
}
*mlen_p = mlen;
}
return ret;
}
int
crypto_aead_chacha20poly1305_ietf_decrypt_detached(unsigned char *m,
unsigned char *nsec,
const unsigned char *c,
unsigned long long clen,
const unsigned char *mac,
const unsigned char *ad,
unsigned long long adlen,
const unsigned char *npub,
const unsigned char *k)
{
crypto_onetimeauth_poly1305_state state;
unsigned char block0[64U];
unsigned char slen[8U];
unsigned char computed_mac[crypto_aead_chacha20poly1305_ietf_ABYTES];
unsigned long long mlen;
int ret;
(void) nsec;
crypto_stream_chacha20_ietf(block0, sizeof block0, npub, k);
crypto_onetimeauth_poly1305_init(&state, block0);
sodium_memzero(block0, sizeof block0);
crypto_onetimeauth_poly1305_update(&state, ad, adlen);
crypto_onetimeauth_poly1305_update(&state, _pad0, (0x10 - adlen) & 0xf);
mlen = clen;
crypto_onetimeauth_poly1305_update(&state, c, mlen);
crypto_onetimeauth_poly1305_update(&state, _pad0, (0x10 - mlen) & 0xf);
STORE64_LE(slen, (uint64_t) adlen);
crypto_onetimeauth_poly1305_update(&state, slen, sizeof slen);
STORE64_LE(slen, (uint64_t) mlen);
crypto_onetimeauth_poly1305_update(&state, slen, sizeof slen);
crypto_onetimeauth_poly1305_final(&state, computed_mac);
sodium_memzero(&state, sizeof state);
(void) sizeof(int[sizeof computed_mac == 16U ? 1 : -1]);
ret = crypto_verify_16(computed_mac, mac);
sodium_memzero(computed_mac, sizeof computed_mac);
if (ret != 0) {
memset(m, 0, mlen);
return -1;
}
crypto_stream_chacha20_ietf_xor_ic(m, c, mlen, npub, 1U, k);
return 0;
}
int
crypto_aead_chacha20poly1305_ietf_decrypt(unsigned char *m,
unsigned long long *mlen_p,
unsigned char *nsec,
const unsigned char *c,
unsigned long long clen,
const unsigned char *ad,
unsigned long long adlen,
const unsigned char *npub,
const unsigned char *k)
{
unsigned long long mlen = 0ULL;
int ret = -1;
if (clen >= crypto_aead_chacha20poly1305_ietf_ABYTES) {
ret = crypto_aead_chacha20poly1305_ietf_decrypt_detached
(m, nsec,
c, clen - crypto_aead_chacha20poly1305_ietf_ABYTES,
c + clen - crypto_aead_chacha20poly1305_ietf_ABYTES,
ad, adlen, npub, k);
}
if (mlen_p != NULL) {
if (ret == 0) {
mlen = clen - crypto_aead_chacha20poly1305_ietf_ABYTES;
}
*mlen_p = mlen;
}
return ret;
}
size_t
crypto_aead_chacha20poly1305_ietf_keybytes(void) {
return crypto_aead_chacha20poly1305_ietf_KEYBYTES;
}
size_t
crypto_aead_chacha20poly1305_ietf_npubbytes(void) {
return crypto_aead_chacha20poly1305_ietf_NPUBBYTES;
}
size_t
crypto_aead_chacha20poly1305_ietf_nsecbytes(void) {
return crypto_aead_chacha20poly1305_ietf_NSECBYTES;
}
size_t
crypto_aead_chacha20poly1305_ietf_abytes(void) {
return crypto_aead_chacha20poly1305_ietf_ABYTES;
}
size_t
crypto_aead_chacha20poly1305_keybytes(void) {
return crypto_aead_chacha20poly1305_KEYBYTES;
}
size_t
crypto_aead_chacha20poly1305_npubbytes(void) {
return crypto_aead_chacha20poly1305_NPUBBYTES;
}
size_t
crypto_aead_chacha20poly1305_nsecbytes(void) {
return crypto_aead_chacha20poly1305_NSECBYTES;
}
size_t
crypto_aead_chacha20poly1305_abytes(void) {
return crypto_aead_chacha20poly1305_ABYTES;
}