325 lines
8.1 KiB
C
Executable file
325 lines
8.1 KiB
C
Executable file
/* $OpenBSD: chacha-merged.c,v 1.9 2019/01/22 00:59:21 dlg Exp $ */
|
|
/*
|
|
chacha-merged.c version 20080118
|
|
D. J. Bernstein
|
|
Public domain.
|
|
*/
|
|
|
|
#include <sys/types.h>
|
|
|
|
#include <stdint.h>
|
|
|
|
#define CHACHA_MINKEYLEN 16
|
|
#define CHACHA_NONCELEN 8
|
|
#define CHACHA_CTRLEN 8
|
|
#define CHACHA_STATELEN (CHACHA_NONCELEN+CHACHA_CTRLEN)
|
|
#define CHACHA_BLOCKLEN 64
|
|
|
|
struct chacha_ctx {
|
|
u_int input[16];
|
|
uint8_t ks[CHACHA_BLOCKLEN];
|
|
uint8_t unused;
|
|
};
|
|
|
|
static inline void chacha_keysetup(struct chacha_ctx *x, const u_char *k,
|
|
u_int kbits)
|
|
__attribute__((__bounded__(__minbytes__, 2, CHACHA_MINKEYLEN)));
|
|
static inline void chacha_ivsetup(struct chacha_ctx *x, const u_char *iv,
|
|
const u_char *ctr)
|
|
__attribute__((__bounded__(__minbytes__, 2, CHACHA_NONCELEN)))
|
|
__attribute__((__bounded__(__minbytes__, 3, CHACHA_CTRLEN)));
|
|
static inline void chacha_encrypt_bytes(struct chacha_ctx *x, const u_char *m,
|
|
u_char *c, u_int bytes)
|
|
__attribute__((__bounded__(__buffer__, 2, 4)))
|
|
__attribute__((__bounded__(__buffer__, 3, 4)));
|
|
|
|
typedef unsigned char u8;
|
|
typedef unsigned int u32;
|
|
|
|
typedef struct chacha_ctx chacha_ctx;
|
|
|
|
#define U8C(v) (v##U)
|
|
#define U32C(v) (v##U)
|
|
|
|
#define U8V(v) ((u8)(v) & U8C(0xFF))
|
|
#define U32V(v) ((u32)(v) & U32C(0xFFFFFFFF))
|
|
|
|
#define ROTL32(v, n) \
|
|
(U32V((v) << (n)) | ((v) >> (32 - (n))))
|
|
|
|
#define U8TO32_LITTLE(p) \
|
|
(((u32)((p)[0])) | \
|
|
((u32)((p)[1]) << 8) | \
|
|
((u32)((p)[2]) << 16) | \
|
|
((u32)((p)[3]) << 24))
|
|
|
|
#define U32TO8_LITTLE(p, v) \
|
|
do { \
|
|
(p)[0] = U8V((v)); \
|
|
(p)[1] = U8V((v) >> 8); \
|
|
(p)[2] = U8V((v) >> 16); \
|
|
(p)[3] = U8V((v) >> 24); \
|
|
} while (0)
|
|
|
|
#define ROTATE(v,c) (ROTL32(v,c))
|
|
#define XOR(v,w) ((v) ^ (w))
|
|
#define PLUS(v,w) (U32V((v) + (w)))
|
|
#define PLUSONE(v) (PLUS((v),1))
|
|
|
|
#define QUARTERROUND(a,b,c,d) \
|
|
a = PLUS(a,b); d = ROTATE(XOR(d,a),16); \
|
|
c = PLUS(c,d); b = ROTATE(XOR(b,c),12); \
|
|
a = PLUS(a,b); d = ROTATE(XOR(d,a), 8); \
|
|
c = PLUS(c,d); b = ROTATE(XOR(b,c), 7);
|
|
|
|
/* Initialise with "expand 32-byte k". */
|
|
static const char sigma[16] = {
|
|
0x65, 0x78, 0x70, 0x61, 0x6e, 0x64, 0x20, 0x33,
|
|
0x32, 0x2d, 0x62, 0x79, 0x74, 0x65, 0x20, 0x6b,
|
|
};
|
|
|
|
/* Initialise with "expand 16-byte k". */
|
|
static const char tau[16] = {
|
|
0x65, 0x78, 0x70, 0x61, 0x6e, 0x64, 0x20, 0x31,
|
|
0x36, 0x2d, 0x62, 0x79, 0x74, 0x65, 0x20, 0x6b,
|
|
};
|
|
|
|
static inline void
|
|
chacha_keysetup(chacha_ctx *x, const u8 *k, u32 kbits)
|
|
{
|
|
const char *constants;
|
|
|
|
x->input[4] = U8TO32_LITTLE(k + 0);
|
|
x->input[5] = U8TO32_LITTLE(k + 4);
|
|
x->input[6] = U8TO32_LITTLE(k + 8);
|
|
x->input[7] = U8TO32_LITTLE(k + 12);
|
|
if (kbits == 256) { /* recommended */
|
|
k += 16;
|
|
constants = sigma;
|
|
} else { /* kbits == 128 */
|
|
constants = tau;
|
|
}
|
|
x->input[8] = U8TO32_LITTLE(k + 0);
|
|
x->input[9] = U8TO32_LITTLE(k + 4);
|
|
x->input[10] = U8TO32_LITTLE(k + 8);
|
|
x->input[11] = U8TO32_LITTLE(k + 12);
|
|
x->input[0] = U8TO32_LITTLE(constants + 0);
|
|
x->input[1] = U8TO32_LITTLE(constants + 4);
|
|
x->input[2] = U8TO32_LITTLE(constants + 8);
|
|
x->input[3] = U8TO32_LITTLE(constants + 12);
|
|
}
|
|
|
|
static inline void
|
|
chacha_ivsetup(chacha_ctx *x, const u8 *iv, const u8 *counter)
|
|
{
|
|
x->input[12] = counter == NULL ? 0 : U8TO32_LITTLE(counter + 0);
|
|
x->input[13] = counter == NULL ? 0 : U8TO32_LITTLE(counter + 4);
|
|
x->input[14] = U8TO32_LITTLE(iv + 0);
|
|
x->input[15] = U8TO32_LITTLE(iv + 4);
|
|
}
|
|
|
|
static inline void
|
|
chacha_encrypt_bytes(chacha_ctx *x, const u8 *m, u8 *c, u32 bytes)
|
|
{
|
|
u32 x0, x1, x2, x3, x4, x5, x6, x7;
|
|
u32 x8, x9, x10, x11, x12, x13, x14, x15;
|
|
u32 j0, j1, j2, j3, j4, j5, j6, j7;
|
|
u32 j8, j9, j10, j11, j12, j13, j14, j15;
|
|
u8 *ctarget = NULL;
|
|
u8 tmp[64];
|
|
u_int i;
|
|
|
|
if (!bytes)
|
|
return;
|
|
|
|
j0 = x->input[0];
|
|
j1 = x->input[1];
|
|
j2 = x->input[2];
|
|
j3 = x->input[3];
|
|
j4 = x->input[4];
|
|
j5 = x->input[5];
|
|
j6 = x->input[6];
|
|
j7 = x->input[7];
|
|
j8 = x->input[8];
|
|
j9 = x->input[9];
|
|
j10 = x->input[10];
|
|
j11 = x->input[11];
|
|
j12 = x->input[12];
|
|
j13 = x->input[13];
|
|
j14 = x->input[14];
|
|
j15 = x->input[15];
|
|
|
|
for (;;) {
|
|
if (bytes < 64) {
|
|
for (i = 0; i < bytes; ++i)
|
|
tmp[i] = m[i];
|
|
m = tmp;
|
|
ctarget = c;
|
|
c = tmp;
|
|
}
|
|
x0 = j0;
|
|
x1 = j1;
|
|
x2 = j2;
|
|
x3 = j3;
|
|
x4 = j4;
|
|
x5 = j5;
|
|
x6 = j6;
|
|
x7 = j7;
|
|
x8 = j8;
|
|
x9 = j9;
|
|
x10 = j10;
|
|
x11 = j11;
|
|
x12 = j12;
|
|
x13 = j13;
|
|
x14 = j14;
|
|
x15 = j15;
|
|
for (i = 20; i > 0; i -= 2) {
|
|
QUARTERROUND(x0, x4, x8, x12)
|
|
QUARTERROUND(x1, x5, x9, x13)
|
|
QUARTERROUND(x2, x6, x10, x14)
|
|
QUARTERROUND(x3, x7, x11, x15)
|
|
QUARTERROUND(x0, x5, x10, x15)
|
|
QUARTERROUND(x1, x6, x11, x12)
|
|
QUARTERROUND(x2, x7, x8, x13)
|
|
QUARTERROUND(x3, x4, x9, x14)
|
|
}
|
|
x0 = PLUS(x0, j0);
|
|
x1 = PLUS(x1, j1);
|
|
x2 = PLUS(x2, j2);
|
|
x3 = PLUS(x3, j3);
|
|
x4 = PLUS(x4, j4);
|
|
x5 = PLUS(x5, j5);
|
|
x6 = PLUS(x6, j6);
|
|
x7 = PLUS(x7, j7);
|
|
x8 = PLUS(x8, j8);
|
|
x9 = PLUS(x9, j9);
|
|
x10 = PLUS(x10, j10);
|
|
x11 = PLUS(x11, j11);
|
|
x12 = PLUS(x12, j12);
|
|
x13 = PLUS(x13, j13);
|
|
x14 = PLUS(x14, j14);
|
|
x15 = PLUS(x15, j15);
|
|
|
|
if (bytes < 64) {
|
|
U32TO8_LITTLE(x->ks + 0, x0);
|
|
U32TO8_LITTLE(x->ks + 4, x1);
|
|
U32TO8_LITTLE(x->ks + 8, x2);
|
|
U32TO8_LITTLE(x->ks + 12, x3);
|
|
U32TO8_LITTLE(x->ks + 16, x4);
|
|
U32TO8_LITTLE(x->ks + 20, x5);
|
|
U32TO8_LITTLE(x->ks + 24, x6);
|
|
U32TO8_LITTLE(x->ks + 28, x7);
|
|
U32TO8_LITTLE(x->ks + 32, x8);
|
|
U32TO8_LITTLE(x->ks + 36, x9);
|
|
U32TO8_LITTLE(x->ks + 40, x10);
|
|
U32TO8_LITTLE(x->ks + 44, x11);
|
|
U32TO8_LITTLE(x->ks + 48, x12);
|
|
U32TO8_LITTLE(x->ks + 52, x13);
|
|
U32TO8_LITTLE(x->ks + 56, x14);
|
|
U32TO8_LITTLE(x->ks + 60, x15);
|
|
}
|
|
|
|
x0 = XOR(x0, U8TO32_LITTLE(m + 0));
|
|
x1 = XOR(x1, U8TO32_LITTLE(m + 4));
|
|
x2 = XOR(x2, U8TO32_LITTLE(m + 8));
|
|
x3 = XOR(x3, U8TO32_LITTLE(m + 12));
|
|
x4 = XOR(x4, U8TO32_LITTLE(m + 16));
|
|
x5 = XOR(x5, U8TO32_LITTLE(m + 20));
|
|
x6 = XOR(x6, U8TO32_LITTLE(m + 24));
|
|
x7 = XOR(x7, U8TO32_LITTLE(m + 28));
|
|
x8 = XOR(x8, U8TO32_LITTLE(m + 32));
|
|
x9 = XOR(x9, U8TO32_LITTLE(m + 36));
|
|
x10 = XOR(x10, U8TO32_LITTLE(m + 40));
|
|
x11 = XOR(x11, U8TO32_LITTLE(m + 44));
|
|
x12 = XOR(x12, U8TO32_LITTLE(m + 48));
|
|
x13 = XOR(x13, U8TO32_LITTLE(m + 52));
|
|
x14 = XOR(x14, U8TO32_LITTLE(m + 56));
|
|
x15 = XOR(x15, U8TO32_LITTLE(m + 60));
|
|
|
|
j12 = PLUSONE(j12);
|
|
if (!j12) {
|
|
j13 = PLUSONE(j13);
|
|
/*
|
|
* Stopping at 2^70 bytes per nonce is the user's
|
|
* responsibility.
|
|
*/
|
|
}
|
|
|
|
U32TO8_LITTLE(c + 0, x0);
|
|
U32TO8_LITTLE(c + 4, x1);
|
|
U32TO8_LITTLE(c + 8, x2);
|
|
U32TO8_LITTLE(c + 12, x3);
|
|
U32TO8_LITTLE(c + 16, x4);
|
|
U32TO8_LITTLE(c + 20, x5);
|
|
U32TO8_LITTLE(c + 24, x6);
|
|
U32TO8_LITTLE(c + 28, x7);
|
|
U32TO8_LITTLE(c + 32, x8);
|
|
U32TO8_LITTLE(c + 36, x9);
|
|
U32TO8_LITTLE(c + 40, x10);
|
|
U32TO8_LITTLE(c + 44, x11);
|
|
U32TO8_LITTLE(c + 48, x12);
|
|
U32TO8_LITTLE(c + 52, x13);
|
|
U32TO8_LITTLE(c + 56, x14);
|
|
U32TO8_LITTLE(c + 60, x15);
|
|
|
|
if (bytes <= 64) {
|
|
if (bytes < 64) {
|
|
for (i = 0; i < bytes; ++i)
|
|
ctarget[i] = c[i];
|
|
}
|
|
x->input[12] = j12;
|
|
x->input[13] = j13;
|
|
x->unused = 64 - bytes;
|
|
return;
|
|
}
|
|
bytes -= 64;
|
|
c += 64;
|
|
m += 64;
|
|
}
|
|
}
|
|
|
|
void
|
|
CRYPTO_hchacha_20(unsigned char subkey[32], const unsigned char key[32],
|
|
const unsigned char nonce[16])
|
|
{
|
|
uint32_t x[16];
|
|
int i;
|
|
|
|
x[0] = U8TO32_LITTLE(sigma + 0);
|
|
x[1] = U8TO32_LITTLE(sigma + 4);
|
|
x[2] = U8TO32_LITTLE(sigma + 8);
|
|
x[3] = U8TO32_LITTLE(sigma + 12);
|
|
x[4] = U8TO32_LITTLE(key + 0);
|
|
x[5] = U8TO32_LITTLE(key + 4);
|
|
x[6] = U8TO32_LITTLE(key + 8);
|
|
x[7] = U8TO32_LITTLE(key + 12);
|
|
x[8] = U8TO32_LITTLE(key + 16);
|
|
x[9] = U8TO32_LITTLE(key + 20);
|
|
x[10] = U8TO32_LITTLE(key + 24);
|
|
x[11] = U8TO32_LITTLE(key + 28);
|
|
x[12] = U8TO32_LITTLE(nonce + 0);
|
|
x[13] = U8TO32_LITTLE(nonce + 4);
|
|
x[14] = U8TO32_LITTLE(nonce + 8);
|
|
x[15] = U8TO32_LITTLE(nonce + 12);
|
|
|
|
for (i = 20; i > 0; i -= 2) {
|
|
QUARTERROUND(x[0], x[4], x[8], x[12])
|
|
QUARTERROUND(x[1], x[5], x[9], x[13])
|
|
QUARTERROUND(x[2], x[6], x[10], x[14])
|
|
QUARTERROUND(x[3], x[7], x[11], x[15])
|
|
QUARTERROUND(x[0], x[5], x[10], x[15])
|
|
QUARTERROUND(x[1], x[6], x[11], x[12])
|
|
QUARTERROUND(x[2], x[7], x[8], x[13])
|
|
QUARTERROUND(x[3], x[4], x[9], x[14])
|
|
}
|
|
|
|
U32TO8_LITTLE(subkey + 0, x[0]);
|
|
U32TO8_LITTLE(subkey + 4, x[1]);
|
|
U32TO8_LITTLE(subkey + 8, x[2]);
|
|
U32TO8_LITTLE(subkey + 12, x[3]);
|
|
|
|
U32TO8_LITTLE(subkey + 16, x[12]);
|
|
U32TO8_LITTLE(subkey + 20, x[13]);
|
|
U32TO8_LITTLE(subkey + 24, x[14]);
|
|
U32TO8_LITTLE(subkey + 28, x[15]);
|
|
}
|