RFC 7539 - ChaCha20 and Poly1305 + chacha based PRNG

This commit is contained in:
Karel Miko
2017-03-21 19:42:54 +01:00
parent 6844275e82
commit ff6abc776c
37 changed files with 1831 additions and 72 deletions
@@ -0,0 +1,34 @@
/* LibTomCrypt, modular cryptographic library -- Tom St Denis
*
* LibTomCrypt is a library that provides various cryptographic
* algorithms in a highly modular and flexible manner.
*
* The library is free for all purposes without any express
* guarantee it works.
*/
#include "tomcrypt.h"
#ifdef LTC_CHACHA20POLY1305_MODE
/**
Add AAD to the ChaCha20Poly1305 state
@param st The ChaCha20Poly1305 state
@param in The additional authentication data to add to the ChaCha20Poly1305 state
@param inlen The length of the ChaCha20Poly1305 data.
@return CRYPT_OK on success
*/
int chacha20poly1305_add_aad(chachapoly_state *st, const unsigned char *in, unsigned long inlen)
{
int err;
if (inlen == 0) return CRYPT_OK; /* nothing to do */
LTC_ARGCHK(st != NULL);
if (st->aadflg == 0) return CRYPT_ERROR;
if ((err = poly1305_process(&st->poly, in, inlen)) != CRYPT_OK) return err;
st->aadlen += (ulong64)inlen;
return CRYPT_OK;
}
#endif
@@ -0,0 +1,44 @@
/* LibTomCrypt, modular cryptographic library -- Tom St Denis
*
* LibTomCrypt is a library that provides various cryptographic
* algorithms in a highly modular and flexible manner.
*
* The library is free for all purposes without any express
* guarantee it works.
*/
#include "tomcrypt.h"
#ifdef LTC_CHACHA20POLY1305_MODE
/**
Decrypt bytes of ciphertext with ChaCha20Poly1305
@param st The ChaCha20Poly1305 state
@param in The ciphertext
@param inlen The length of the input (octets)
@param out [out] The plaintext (length inlen)
@return CRYPT_OK if successful
*/
int chacha20poly1305_decrypt(chachapoly_state *st, const unsigned char *in, unsigned long inlen, unsigned char *out)
{
unsigned char padzero[16] = { 0 };
unsigned long padlen;
int err;
if (inlen == 0) return CRYPT_OK; /* nothing to do */
LTC_ARGCHK(st != NULL);
if (st->aadflg) {
if ((padlen = 16 - (st->aadlen % 16)) < 16) {
if ((err = poly1305_process(&st->poly, padzero, padlen)) != CRYPT_OK) return err;
}
st->aadflg = 0; /* no more AAD */
}
if (st->aadflg) st->aadflg = 0; /* no more AAD */
if ((err = poly1305_process(&st->poly, in, inlen)) != CRYPT_OK) return err;
if ((err = chacha_crypt(&st->chacha, in, inlen, out)) != CRYPT_OK) return err;
st->ctlen += (ulong64)inlen;
return CRYPT_OK;
}
#endif
@@ -0,0 +1,41 @@
/* LibTomCrypt, modular cryptographic library -- Tom St Denis
*
* LibTomCrypt is a library that provides various cryptographic
* algorithms in a highly modular and flexible manner.
*
* The library is free for all purposes without any express
* guarantee it works.
*/
#include "tomcrypt.h"
#ifdef LTC_CHACHA20POLY1305_MODE
/**
Terminate a ChaCha20Poly1305 stream
@param st The ChaCha20Poly1305 state
@param tag [out] The destination for the MAC tag
@param taglen [in/out] The length of the MAC tag
@return CRYPT_OK on success
*/
int chacha20poly1305_done(chachapoly_state *st, unsigned char *tag, unsigned long *taglen)
{
unsigned char padzero[16] = { 0 };
unsigned long padlen;
unsigned char buf[16];
int err;
LTC_ARGCHK(st != NULL);
padlen = 16 - (st->ctlen % 16);
if (padlen < 16) {
if ((err = poly1305_process(&st->poly, padzero, padlen)) != CRYPT_OK) return err;
}
STORE64L(st->aadlen, buf);
STORE64L(st->ctlen, buf + 8);
if ((err = poly1305_process(&st->poly, buf, 16)) != CRYPT_OK) return err;
if ((err = poly1305_done(&st->poly, tag, taglen)) != CRYPT_OK) return err;
return CRYPT_OK;
}
#endif
@@ -0,0 +1,44 @@
/* LibTomCrypt, modular cryptographic library -- Tom St Denis
*
* LibTomCrypt is a library that provides various cryptographic
* algorithms in a highly modular and flexible manner.
*
* The library is free for all purposes without any express
* guarantee it works.
*/
#include "tomcrypt.h"
#ifdef LTC_CHACHA20POLY1305_MODE
/**
Encrypt bytes of ciphertext with ChaCha20Poly1305
@param st The ChaCha20Poly1305 state
@param in The plaintext
@param inlen The length of the input (octets)
@param out [out] The ciphertext (length inlen)
@return CRYPT_OK if successful
*/
int chacha20poly1305_encrypt(chachapoly_state *st, const unsigned char *in, unsigned long inlen, unsigned char *out)
{
unsigned char padzero[16] = { 0 };
unsigned long padlen;
int err;
if (inlen == 0) return CRYPT_OK; /* nothing to do */
LTC_ARGCHK(st != NULL);
if ((err = chacha_crypt(&st->chacha, in, inlen, out)) != CRYPT_OK) return err;
if (st->aadflg) {
padlen = 16 - (st->aadlen % 16);
if (padlen < 16) {
if ((err = poly1305_process(&st->poly, padzero, padlen)) != CRYPT_OK) return err;
}
st->aadflg = 0; /* no more AAD */
}
if ((err = poly1305_process(&st->poly, out, inlen)) != CRYPT_OK) return err;
st->ctlen += (ulong64)inlen;
return CRYPT_OK;
}
#endif
@@ -0,0 +1,26 @@
/* LibTomCrypt, modular cryptographic library -- Tom St Denis
*
* LibTomCrypt is a library that provides various cryptographic
* algorithms in a highly modular and flexible manner.
*
* The library is free for all purposes without any express
* guarantee it works.
*/
#include "tomcrypt.h"
#ifdef LTC_CHACHA20POLY1305_MODE
/**
Initialize an ChaCha20Poly1305 context (only the key)
@param st [out] The destination of the ChaCha20Poly1305 state
@param key The secret key
@param keylen The length of the secret key (octets)
@return CRYPT_OK if successful
*/
int chacha20poly1305_init(chachapoly_state *st, const unsigned char *key, unsigned long keylen)
{
return chacha_setup(&st->chacha, key, keylen, 20);
}
#endif
@@ -0,0 +1,70 @@
/* LibTomCrypt, modular cryptographic library -- Tom St Denis
*
* LibTomCrypt is a library that provides various cryptographic
* algorithms in a highly modular and flexible manner.
*
* The library is free for all purposes without any express
* guarantee it works.
*/
#include "tomcrypt.h"
#ifdef LTC_CHACHA20POLY1305_MODE
/**
Process an entire GCM packet in one call.
@param key The secret key
@param keylen The length of the secret key
@param iv The initial vector
@param ivlen The length of the initial vector
@param aad The additional authentication data (header)
@param aadlen The length of the aad
@param in The plaintext
@param inlen The length of the plaintext (ciphertext length is the same)
@param out The ciphertext
@param tag [out] The MAC tag
@param taglen [in/out] The MAC tag length
@param direction Encrypt or Decrypt mode (CHCHA20POLY1305_ENCRYPT or CHCHA20POLY1305_DECRYPT)
@return CRYPT_OK on success
*/
int chacha20poly1305_memory(const unsigned char *key, unsigned long keylen,
const unsigned char *iv, unsigned long ivlen,
const unsigned char *aad, unsigned long aadlen,
const unsigned char *in, unsigned long inlen,
unsigned char *out,
unsigned char *tag, unsigned long *taglen,
int direction)
{
chachapoly_state st;
int err;
LTC_ARGCHK(key != NULL);
LTC_ARGCHK(iv != NULL);
LTC_ARGCHK(in != NULL);
LTC_ARGCHK(out != NULL);
LTC_ARGCHK(tag != NULL);
if ((err = chacha20poly1305_init(&st, key, keylen)) != CRYPT_OK) { goto LBL_ERR; }
if ((err = chacha20poly1305_setiv(&st, iv, ivlen)) != CRYPT_OK) { goto LBL_ERR; }
if (aad && aadlen > 0) {
if ((err = chacha20poly1305_add_aad(&st, aad, aadlen)) != CRYPT_OK) { goto LBL_ERR; }
}
if (direction == CHCHA20POLY1305_ENCRYPT) {
if ((err = chacha20poly1305_encrypt(&st, in, inlen, out)) != CRYPT_OK) { goto LBL_ERR; }
}
else if (direction == CHCHA20POLY1305_DECRYPT) {
if ((err = chacha20poly1305_decrypt(&st, in, inlen, out)) != CRYPT_OK) { goto LBL_ERR; }
}
else {
err = CRYPT_INVALID_ARG;
goto LBL_ERR;
}
err = chacha20poly1305_done(&st, tag, taglen);
LBL_ERR:
#ifdef LTC_CLEAN_STACK
zeromem(&st, sizeof(chachapoly_state));
#endif
return err;
}
#endif
@@ -0,0 +1,64 @@
/* LibTomCrypt, modular cryptographic library -- Tom St Denis
*
* LibTomCrypt is a library that provides various cryptographic
* algorithms in a highly modular and flexible manner.
*
* The library is free for all purposes without any express
* guarantee it works.
*/
#include "tomcrypt.h"
#ifdef LTC_CHACHA20POLY1305_MODE
/**
Set IV + counter data to the ChaCha20Poly1305 state and reset the context
@param st The ChaCha20Poly1305 state
@param iv The IV data to add
@param inlen The length of the IV (must be 12 or 8)
@return CRYPT_OK on success
*/
int chacha20poly1305_setiv(chachapoly_state *st, const unsigned char *iv, unsigned long ivlen)
{
chacha_state tmp_st;
int i, err;
unsigned char polykey[32];
LTC_ARGCHK(st != NULL);
LTC_ARGCHK(iv != NULL);
LTC_ARGCHK(ivlen == 12 || ivlen == 8);
/* set IV for chacha20 */
if (ivlen == 12) {
/* IV 96bit */
if ((err = chacha_ivctr32(&st->chacha, iv, ivlen, 1)) != CRYPT_OK) return err;
}
else {
/* IV 64bit */
if ((err = chacha_ivctr64(&st->chacha, iv, ivlen, 1)) != CRYPT_OK) return err;
}
/* copy chacha20 key to temporary state */
for(i = 0; i < 12; i++) tmp_st.input[i] = st->chacha.input[i];
tmp_st.rounds = 20;
/* set IV */
if (ivlen == 12) {
/* IV 32bit */
if ((err = chacha_ivctr32(&tmp_st, iv, ivlen, 0)) != CRYPT_OK) return err;
}
else {
/* IV 64bit */
if ((err = chacha_ivctr64(&tmp_st, iv, ivlen, 0)) != CRYPT_OK) return err;
}
/* (re)generate new poly1305 key */
if ((err = chacha_keystream(&tmp_st, polykey, 32)) != CRYPT_OK) return err;
/* (re)initialise poly1305 */
if ((err = poly1305_init(&st->poly, polykey, 32)) != CRYPT_OK) return err;
st->ctlen = 0;
st->aadlen = 0;
st->aadflg = 1;
return CRYPT_OK;
}
#endif
@@ -0,0 +1,36 @@
/* LibTomCrypt, modular cryptographic library -- Tom St Denis
*
* LibTomCrypt is a library that provides various cryptographic
* algorithms in a highly modular and flexible manner.
*
* The library is free for all purposes without any express
* guarantee it works.
*/
#include "tomcrypt.h"
#ifdef LTC_CHACHA20POLY1305_MODE
/**
Set IV + counter data (with RFC7905-magic) to the ChaCha20Poly1305 state and reset the context
@param st The ChaCha20Poly1305 state
@param iv The IV data to add
@param inlen The length of the IV (must be 12 or 8)
@param sequence_number 64bit sequence number which is incorporated into IV as described in RFC7905
@return CRYPT_OK on success
*/
int chacha20poly1305_setiv_rfc7905(chachapoly_state *st, const unsigned char *iv, unsigned long ivlen, ulong64 sequence_number)
{
int i;
unsigned char combined_iv[12] = { 0 };
LTC_ARGCHK(st != NULL);
LTC_ARGCHK(iv != NULL);
LTC_ARGCHK(ivlen == 12);
STORE64L(sequence_number, combined_iv + 4);
for (i = 0; i < 12; i++) combined_iv[i] = iv[i] ^ combined_iv[i];
return chacha20poly1305_setiv(st, combined_iv, 12);
}
#endif
@@ -0,0 +1,70 @@
/* LibTomCrypt, modular cryptographic library -- Tom St Denis
*
* LibTomCrypt is a library that provides various cryptographic
* algorithms in a highly modular and flexible manner.
*
* The library is free for all purposes without any express
* guarantee it works.
*/
#include "tomcrypt.h"
#ifdef LTC_CHACHA20POLY1305_MODE
int chacha20poly1305_test(void)
{
#ifndef LTC_TEST
return CRYPT_NOP;
#else
chachapoly_state st1, st2;
unsigned char k[] = { 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f };
unsigned char iv[] = { 0x07, 0x00, 0x00, 0x00, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47 };
unsigned char aad[] = { 0x50, 0x51, 0x52, 0x53, 0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7 };
unsigned char enc[] = { 0xD3, 0x1A, 0x8D, 0x34, 0x64, 0x8E, 0x60, 0xDB, 0x7B, 0x86, 0xAF, 0xBC, 0x53, 0xEF, 0x7E, 0xC2,
0xA4, 0xAD, 0xED, 0x51, 0x29, 0x6E, 0x08, 0xFE, 0xA9, 0xE2, 0xB5, 0xA7, 0x36, 0xEE, 0x62, 0xD6,
0x3D, 0xBE, 0xA4, 0x5E, 0x8C, 0xA9, 0x67, 0x12, 0x82, 0xFA, 0xFB, 0x69, 0xDA, 0x92, 0x72, 0x8B,
0x1A, 0x71, 0xDE, 0x0A, 0x9E, 0x06, 0x0B, 0x29, 0x05, 0xD6, 0xA5, 0xB6, 0x7E, 0xCD, 0x3B, 0x36,
0x92, 0xDD, 0xBD, 0x7F, 0x2D, 0x77, 0x8B, 0x8C, 0x98, 0x03, 0xAE, 0xE3, 0x28, 0x09, 0x1B, 0x58,
0xFA, 0xB3, 0x24, 0xE4, 0xFA, 0xD6, 0x75, 0x94, 0x55, 0x85, 0x80, 0x8B, 0x48, 0x31, 0xD7, 0xBC,
0x3F, 0xF4, 0xDE, 0xF0, 0x8E, 0x4B, 0x7A, 0x9D, 0xE5, 0x76, 0xD2, 0x65, 0x86, 0xCE, 0xC6, 0x4B,
0x61, 0x16 };
unsigned char tag[] = { 0x1A, 0xE1, 0x0B, 0x59, 0x4F, 0x09, 0xE2, 0x6A, 0x7E, 0x90, 0x2E, 0xCB, 0xD0, 0x60, 0x06, 0x91 };
char m[] = "Ladies and Gentlemen of the class of '99: If I could offer you only one tip for the future, sunscreen would be it.";
unsigned long mlen = strlen(m);
unsigned long len;
unsigned char ct[1000], pt[1000], emac[16], dmac[16];
/* encrypt */
chacha20poly1305_init(&st1, k, sizeof(k));
chacha20poly1305_setiv(&st1, iv, sizeof(iv));
chacha20poly1305_add_aad(&st1, aad, sizeof(aad));
/* encrypt piece by piece */
chacha20poly1305_encrypt(&st1, (unsigned char *)m, 25, ct);
chacha20poly1305_encrypt(&st1, (unsigned char *)m + 25, 10, ct + 25);
chacha20poly1305_encrypt(&st1, (unsigned char *)m + 35, 35, ct + 35);
chacha20poly1305_encrypt(&st1, (unsigned char *)m + 70, 5, ct + 70);
chacha20poly1305_encrypt(&st1, (unsigned char *)m + 75, 5, ct + 75);
chacha20poly1305_encrypt(&st1, (unsigned char *)m + 80, mlen - 80, ct + 80);
len = sizeof(emac);
chacha20poly1305_done(&st1, emac, &len);
if (compare_testvector(ct, mlen, enc, sizeof(enc), "ENC-CT", 1) != 0) return CRYPT_FAIL_TESTVECTOR;
if (compare_testvector(emac, len, tag, sizeof(tag), "ENC-TAG", 2) != 0) return CRYPT_FAIL_TESTVECTOR;
/* decrypt */
chacha20poly1305_init(&st2, k, len = sizeof(k));
chacha20poly1305_setiv(&st2, iv, len = sizeof(iv));
chacha20poly1305_add_aad(&st2, aad, len = sizeof(aad));
chacha20poly1305_decrypt(&st2, ct, 21, pt);
chacha20poly1305_decrypt(&st2, ct + 21, mlen - 21, pt + 21);
len = sizeof(dmac);
chacha20poly1305_done(&st2, dmac, &len);
if (compare_testvector(pt, mlen, m, mlen, "DEC-PT", 3) != 0) return CRYPT_FAIL_TESTVECTOR;
if (compare_testvector(dmac, len, tag, sizeof(tag), "DEC-TAG", 4) != 0) return CRYPT_FAIL_TESTVECTOR;
return CRYPT_OK;
#endif
};
#endif