GRASSHOPPER_CIPHER_CBC,
GRASSHOPPER_CIPHER_OFB,
GRASSHOPPER_CIPHER_CFB,
- GRASSHOPPER_CIPHER_CTR
+ GRASSHOPPER_CIPHER_CTR,
+ GRASSHOPPER_CIPHER_CTRACPKM,
};
-static EVP_CIPHER* gost_grasshopper_ciphers[5] = {
+static EVP_CIPHER* gost_grasshopper_ciphers[6] = {
[GRASSHOPPER_CIPHER_ECB] = NULL,
[GRASSHOPPER_CIPHER_CBC] = NULL,
[GRASSHOPPER_CIPHER_OFB] = NULL,
[GRASSHOPPER_CIPHER_CFB] = NULL,
- [GRASSHOPPER_CIPHER_CTR] = NULL
+ [GRASSHOPPER_CIPHER_CTR] = NULL,
+ [GRASSHOPPER_CIPHER_CTRACPKM] = NULL,
};
static GRASSHOPPER_INLINE void gost_grasshopper_cipher_destroy_ofb(gost_grasshopper_cipher_ctx* c);
bool padding;
};
-static struct GRASSHOPPER_CIPHER_PARAMS gost_cipher_params[5] = {
+static struct GRASSHOPPER_CIPHER_PARAMS gost_cipher_params[6] = {
[GRASSHOPPER_CIPHER_ECB] = {
NID_grasshopper_ecb,
gost_grasshopper_cipher_init_ecb,
gost_grasshopper_cipher_destroy_ctr,
1,
sizeof(gost_grasshopper_cipher_ctx_ctr),
- 8,
+ /* IV size is set to match full block, to make it responsibility of
+ * user to assign correct values (IV || 0), and to make naive context
+ * copy possible (for software such as openssh) */
+ 16,
false
},
+ [GRASSHOPPER_CIPHER_CTRACPKM] = {
+ NID_id_tc26_cipher_gostr3412_2015_kuznyechik_ctracpkm,
+ gost_grasshopper_cipher_init_ctracpkm,
+ gost_grasshopper_cipher_do_ctracpkm,
+ gost_grasshopper_cipher_destroy_ctr,
+ 1,
+ sizeof(gost_grasshopper_cipher_ctx_ctr),
+ 16,
+ false
+ },
+};
+
+/* first 256 bit of D from draft-irtf-cfrg-re-keying-12 */
+static const unsigned char ACPKM_D_2018[] = {
+ 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, /* 64 bit */
+ 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, /* 128 bit */
+ 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
+ 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, /* 256 bit */
};
+static void acpkm_next(gost_grasshopper_cipher_ctx *c)
+{
+ unsigned char newkey[GRASSHOPPER_KEY_SIZE];
+ const int J = GRASSHOPPER_KEY_SIZE / GRASSHOPPER_BLOCK_SIZE;
+ int n;
+
+ for (n = 0; n < J; n++) {
+ const unsigned char *D_n = &ACPKM_D_2018[n * GRASSHOPPER_BLOCK_SIZE];
+
+ grasshopper_encrypt_block(&c->encrypt_round_keys,
+ (grasshopper_w128_t *)D_n,
+ (grasshopper_w128_t *)&newkey[n * GRASSHOPPER_BLOCK_SIZE],
+ &c->buffer);
+ }
+ gost_grasshopper_cipher_key(c, newkey);
+}
+
/* Set 256 bit key into context */
GRASSHOPPER_INLINE void gost_grasshopper_cipher_key(gost_grasshopper_cipher_ctx* c, const uint8_t* k) {
int i;
static GRASSHOPPER_INLINE void gost_grasshopper_cipher_destroy_ctr(gost_grasshopper_cipher_ctx* c) {
gost_grasshopper_cipher_ctx_ctr* ctx = (gost_grasshopper_cipher_ctx_ctr*) c;
- grasshopper_zero128(&ctx->iv_buffer);
grasshopper_zero128(&ctx->partial_buffer);
}
gost_grasshopper_cipher_ctx_ctr* c = EVP_CIPHER_CTX_get_cipher_data(ctx);
c->c.type = GRASSHOPPER_CIPHER_CTR;
- ctx->num = 0;
+ EVP_CIPHER_CTX_set_num(ctx, 0);
- grasshopper_zero128(&c->iv_buffer);
grasshopper_zero128(&c->partial_buffer);
return gost_grasshopper_cipher_init(ctx, key, iv, enc);
}
+GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_ctracpkm(EVP_CIPHER_CTX *ctx, const unsigned char *key,
+ const unsigned char *iv,
+ int enc) {
+ gost_grasshopper_cipher_ctx_ctr *c = EVP_CIPHER_CTX_get_cipher_data(ctx);
+
+ /* NB: setting type makes EVP do_cipher callback useless */
+ c->c.type = GRASSHOPPER_CIPHER_CTRACPKM;
+ EVP_CIPHER_CTX_set_num(ctx, 0);
+ c->section_size = 4096;
+
+ return gost_grasshopper_cipher_init(ctx, key, iv, enc);
+}
+
GRASSHOPPER_INLINE int gost_grasshopper_cipher_do(EVP_CIPHER_CTX* ctx, unsigned char* out,
const unsigned char* in, size_t inl) {
gost_grasshopper_cipher_ctx* c = (gost_grasshopper_cipher_ctx*) EVP_CIPHER_CTX_get_cipher_data(ctx);
unsigned char* current_out = out;
grasshopper_w128_t* currentInputBlock;
grasshopper_w128_t* currentOutputBlock;
- unsigned int n = ctx->num;
+ unsigned int n = EVP_CIPHER_CTX_num(ctx);
size_t lasted;
size_t i;
--inl;
n = (n + 1) % GRASSHOPPER_BLOCK_SIZE;
}
- ctx->num = n;
+ EVP_CIPHER_CTX_set_num(ctx, n);
size_t blocks = inl / GRASSHOPPER_BLOCK_SIZE;
- memcpy(&c->iv_buffer, iv, 8);
+ grasshopper_w128_t* iv_buffer = (grasshopper_w128_t*) iv;
// full parts
for (i = 0; i < blocks; i++) {
currentInputBlock = (grasshopper_w128_t*) current_in;
currentOutputBlock = (grasshopper_w128_t*) current_out;
- grasshopper_encrypt_block(&c->c.encrypt_round_keys, &c->iv_buffer, currentOutputBlock, &c->c.buffer);
+ grasshopper_encrypt_block(&c->c.encrypt_round_keys, iv_buffer, currentOutputBlock, &c->c.buffer);
grasshopper_append128(currentOutputBlock, currentInputBlock);
- ctr128_inc(c->iv_buffer.b);
+ ctr128_inc(iv_buffer->b);
current_in += GRASSHOPPER_BLOCK_SIZE;
current_out += GRASSHOPPER_BLOCK_SIZE;
}
if (lasted > 0) {
currentInputBlock = (grasshopper_w128_t*) current_in;
currentOutputBlock = (grasshopper_w128_t*) current_out;
- grasshopper_encrypt_block(&c->c.encrypt_round_keys, &c->iv_buffer, &c->partial_buffer, &c->c.buffer);
+ grasshopper_encrypt_block(&c->c.encrypt_round_keys, iv_buffer, &c->partial_buffer, &c->c.buffer);
for (i = 0; i < lasted; i++) {
currentOutputBlock->b[i] = c->partial_buffer.b[i] ^ currentInputBlock->b[i];
}
- ctx->num = i;
- ctr128_inc(c->iv_buffer.b);
+ EVP_CIPHER_CTX_set_num(ctx, i);
+ ctr128_inc(iv_buffer->b);
+ }
+
+ return 1;
+}
+
+#define GRASSHOPPER_BLOCK_MASK (GRASSHOPPER_BLOCK_SIZE - 1)
+static inline void apply_acpkm_grasshopper(gost_grasshopper_cipher_ctx_ctr *ctx, unsigned int *num)
+{
+ if (!ctx->section_size ||
+ (*num < ctx->section_size))
+ return;
+ acpkm_next(&ctx->c);
+ *num &= GRASSHOPPER_BLOCK_MASK;
+}
+
+/* If meshing is not configured via ctrl (setting section_size)
+ * this function works exactly like plain ctr */
+int gost_grasshopper_cipher_do_ctracpkm(EVP_CIPHER_CTX *ctx, unsigned char *out,
+ const unsigned char *in, size_t inl) {
+ gost_grasshopper_cipher_ctx_ctr *c = EVP_CIPHER_CTX_get_cipher_data(ctx);
+ unsigned char *iv = EVP_CIPHER_CTX_iv_noconst(ctx);
+ unsigned int num = EVP_CIPHER_CTX_num(ctx);
+
+ while ((num & GRASSHOPPER_BLOCK_MASK) && inl) {
+ *out++ = *in++ ^ c->partial_buffer.b[num & GRASSHOPPER_BLOCK_MASK];
+ --inl;
+ num++;
+ }
+ size_t blocks = inl / GRASSHOPPER_BLOCK_SIZE;
+ size_t i;
+
+ // full parts
+ for (i = 0; i < blocks; i++) {
+ apply_acpkm_grasshopper(c, &num);
+ grasshopper_encrypt_block(&c->c.encrypt_round_keys,
+ (grasshopper_w128_t *)iv, (grasshopper_w128_t *)out, &c->c.buffer);
+ grasshopper_append128((grasshopper_w128_t *)out, (grasshopper_w128_t *)in);
+ ctr128_inc(iv);
+ in += GRASSHOPPER_BLOCK_SIZE;
+ out += GRASSHOPPER_BLOCK_SIZE;
+ num += GRASSHOPPER_BLOCK_SIZE;
}
+ // last part
+ size_t lasted = inl - blocks * GRASSHOPPER_BLOCK_SIZE;
+ if (lasted > 0) {
+ apply_acpkm_grasshopper(c, &num);
+ grasshopper_encrypt_block(&c->c.encrypt_round_keys,
+ (grasshopper_w128_t *)iv, &c->partial_buffer, &c->c.buffer);
+ for (i = 0; i < lasted; i++)
+ out[i] = c->partial_buffer.b[i] ^ in[i];
+ ctr128_inc(iv);
+ num += lasted;
+ }
+ EVP_CIPHER_CTX_set_num(ctx, num);
+
return 1;
}
int gost_grasshopper_cipher_cleanup(EVP_CIPHER_CTX* ctx) {
gost_grasshopper_cipher_ctx* c = (gost_grasshopper_cipher_ctx*) EVP_CIPHER_CTX_get_cipher_data(ctx);
+
+ if (!c)
+ return 1;
+
struct GRASSHOPPER_CIPHER_PARAMS* params = &gost_cipher_params[c->type];
gost_grasshopper_cipher_destroy(c);
}
break;
}
+ case EVP_CTRL_KEY_MESH: {
+ gost_grasshopper_cipher_ctx_ctr *c = EVP_CIPHER_CTX_get_cipher_data(ctx);
+ if (c->c.type != GRASSHOPPER_CIPHER_CTRACPKM ||
+ !arg || (arg % GRASSHOPPER_BLOCK_SIZE))
+ return -1;
+ c->section_size = arg;
+ break;
+ }
default:
GOSTerr(GOST_F_GOST_GRASSHOPPER_CIPHER_CTL, GOST_R_UNSUPPORTED_CIPHER_CTL_COMMAND);
return -1;
return cipher_gost_grasshopper(EVP_CIPH_CTR_MODE, GRASSHOPPER_CIPHER_CTR);
}
+const GRASSHOPPER_INLINE EVP_CIPHER* cipher_gost_grasshopper_ctracpkm() {
+ return cipher_gost_grasshopper(EVP_CIPH_CTR_MODE, GRASSHOPPER_CIPHER_CTRACPKM);
+}
+
void cipher_gost_grasshopper_destroy(void)
{
EVP_CIPHER_meth_free(gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_ECB]);
gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_CFB] = NULL;
EVP_CIPHER_meth_free(gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_CTR]);
gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_CTR] = NULL;
+ EVP_CIPHER_meth_free(gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_CTRACPKM]);
+ gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_CTRACPKM] = NULL;
}
#if defined(__cplusplus)