SEXP R_stream_chacha20(SEXP n, SEXP key, SEXP nonce){
if(LENGTH(key) != crypto_stream_chacha20_KEYBYTES)
Rf_error("Invalid key, must be exactly %d bytes", crypto_stream_chacha20_KEYBYTES);
if(LENGTH(nonce) != crypto_stream_chacha20_NONCEBYTES)
Rf_error("Invalid nonce, must be exactly %d bytes", crypto_stream_chacha20_NONCEBYTES);
unsigned long long clen = (unsigned long long) asReal(n);
SEXP res = allocVector(RAWSXP, clen);
crypto_stream_chacha20(RAW(res), clen, RAW(nonce), RAW(key));
return res;
}
int
crypto_stream_xchacha20(unsigned char *c, unsigned long long clen,
const unsigned char *n, const unsigned char *k)
{
unsigned char k2[crypto_core_hchacha20_OUTPUTBYTES];
crypto_core_hchacha20(k2, n, k, NULL);
assert(crypto_stream_chacha20_KEYBYTES <= sizeof k2);
assert(crypto_stream_chacha20_NONCEBYTES ==
(sizeof n) - crypto_core_hchacha20_INPUTBYTES);
return crypto_stream_chacha20(c, clen,
n + crypto_core_hchacha20_INPUTBYTES, k2);
}
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);
COMPILER_ASSERT(sizeof computed_mac == 16U);
ret = crypto_verify_16(computed_mac, mac);
sodium_memzero(computed_mac, sizeof computed_mac);
if (m == NULL) {
return ret;
}
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_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;
}
static
void tv(void)
{
static struct {
const char *key_hex;
const char *nonce_hex;
} tests[]
= { { "0000000000000000000000000000000000000000000000000000000000000000",
"0000000000000000" },
{ "0000000000000000000000000000000000000000000000000000000000000001",
"0000000000000000" },
{ "0000000000000000000000000000000000000000000000000000000000000000",
"0000000000000001" },
{ "0000000000000000000000000000000000000000000000000000000000000000",
"0100000000000000" },
{ "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f",
"0001020304050607" } };
unsigned char key[crypto_stream_chacha20_KEYBYTES];
unsigned char nonce[crypto_stream_chacha20_NONCEBYTES];
unsigned char *part;
unsigned char out[160];
unsigned char zero[160];
char out_hex[160 * 2 + 1];
size_t i = 0U;
size_t plen;
memset(zero, 0, sizeof zero);
do {
sodium_hex2bin((unsigned char *)key, sizeof key, tests[i].key_hex,
strlen(tests[i].key_hex), NULL, NULL, NULL);
sodium_hex2bin(nonce, sizeof nonce, tests[i].nonce_hex,
strlen(tests[i].nonce_hex), NULL, NULL, NULL);
crypto_stream_chacha20(out, sizeof out, nonce, key);
sodium_bin2hex(out_hex, sizeof out_hex, out, sizeof out);
printf("[%s]\n", out_hex);
for (plen = 1U; plen < sizeof out; plen++) {
part = (unsigned char *) sodium_malloc(plen);
crypto_stream_chacha20_xor(part, out, plen, nonce, key);
if (memcmp(part, zero, plen) != 0) {
printf("Failed with length %lu\n", (unsigned long) plen);
}
sodium_free(part);
}
} while (++i < (sizeof tests) / (sizeof tests[0]));
randombytes_buf(out, sizeof out);
crypto_stream_chacha20(out, sizeof out, nonce, key);
sodium_bin2hex(out_hex, sizeof out_hex, out, sizeof out);
printf("[%s]\n", out_hex);
assert(crypto_stream_chacha20(out, 0U, nonce, key) == 0);
assert(crypto_stream_chacha20_xor(out, out, 0U, nonce, key) == 0);
assert(crypto_stream_chacha20_xor(out, out, 0U, nonce, key) == 0);
assert(crypto_stream_chacha20_xor_ic(out, out, 0U, nonce, 1U, key) == 0);
memset(out, 0x42, sizeof out);
crypto_stream_chacha20_xor(out, out, sizeof out, nonce, key);
sodium_bin2hex(out_hex, sizeof out_hex, out, sizeof out);
printf("[%s]\n", out_hex);
crypto_stream_chacha20_xor_ic(out, out, sizeof out, nonce, 0U, key);
sodium_bin2hex(out_hex, sizeof out_hex, out, sizeof out);
printf("[%s]\n", out_hex);
crypto_stream_chacha20_xor_ic(out, out, sizeof out, nonce, 1U, key);
sodium_bin2hex(out_hex, sizeof out_hex, out, sizeof out);
printf("[%s]\n", out_hex);
};
