]> www.wagner.pp.ru Git - openssl-gost/engine.git/blobdiff - gost_grasshopper_cipher.c
Make it possible to re-define OPENSSL_ENGINES_INSTALL_DIR
[openssl-gost/engine.git] / gost_grasshopper_cipher.c
index 6adc3802a34ee688b6c88510620471f4bb06062d..e78fae747db56dca65fc677e00a7b4d27425afbd 100644 (file)
@@ -17,6 +17,7 @@ extern "C" {
 #include <openssl/err.h>
 #include <string.h>
 
+#include "gost_lcl.h"
 #include "e_gost_err.h"
 
 enum GRASSHOPPER_CIPHER_TYPE {
@@ -24,15 +25,17 @@ enum GRASSHOPPER_CIPHER_TYPE {
     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);
@@ -49,7 +52,7 @@ struct GRASSHOPPER_CIPHER_PARAMS {
     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,
@@ -96,15 +99,54 @@ static struct GRASSHOPPER_CIPHER_PARAMS gost_cipher_params[5] = {
                 gost_grasshopper_cipher_do_ctr,
                 gost_grasshopper_cipher_destroy_ctr,
                 1,
-                sizeof(gost_grasshopper_cipher_ctx),
-                8,
+                sizeof(gost_grasshopper_cipher_ctx_ctr),
+               /* 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 */
-static GRASSHOPPER_INLINE void gost_grasshopper_cipher_key(gost_grasshopper_cipher_ctx* c, const uint8_t* k) {
-    for (int i = 0; i < 2; i++) {
+GRASSHOPPER_INLINE void gost_grasshopper_cipher_key(gost_grasshopper_cipher_ctx* c, const uint8_t* k) {
+               int i;
+    for (i = 0; i < 2; i++) {
         grasshopper_copy128(&c->key.k.k[i], (const grasshopper_w128_t*) (k + i * 16));
     }
     grasshopper_set_encrypt_key(&c->encrypt_round_keys, &c->key);
@@ -112,14 +154,15 @@ static GRASSHOPPER_INLINE void gost_grasshopper_cipher_key(gost_grasshopper_ciph
 }
 
 /* Cleans up key from context */
-static GRASSHOPPER_INLINE void gost_grasshopper_cipher_destroy(gost_grasshopper_cipher_ctx* c) {
-    for (int i = 0; i < 2; i++) {
+GRASSHOPPER_INLINE void gost_grasshopper_cipher_destroy(gost_grasshopper_cipher_ctx* c) {
+               int i;
+    for (i = 0; i < 2; i++) {
         grasshopper_zero128(&c->key.k.k[i]);
     }
-    for (int i = 0; i < GRASSHOPPER_ROUND_KEYS_COUNT; i++) {
+    for (i = 0; i < GRASSHOPPER_ROUND_KEYS_COUNT; i++) {
         grasshopper_zero128(&c->encrypt_round_keys.k[i]);
     }
-    for (int i = 0; i < GRASSHOPPER_ROUND_KEYS_COUNT; i++) {
+    for (i = 0; i < GRASSHOPPER_ROUND_KEYS_COUNT; i++) {
         grasshopper_zero128(&c->decrypt_round_keys.k[i]);
     }
     grasshopper_zero128(&c->buffer);
@@ -134,18 +177,15 @@ static GRASSHOPPER_INLINE void gost_grasshopper_cipher_destroy_ofb(gost_grasshop
 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);
-
-    ctx->counter = 0;
 }
 
-static int gost_grasshopper_cipher_init(EVP_CIPHER_CTX* ctx, const unsigned char* key,
+int gost_grasshopper_cipher_init(EVP_CIPHER_CTX* ctx, const unsigned char* key,
                                         const unsigned char* iv, int enc) {
-    gost_grasshopper_cipher_ctx* c = EVP_CIPHER_CTX_cipher_data(ctx);
+    gost_grasshopper_cipher_ctx* c = EVP_CIPHER_CTX_get_cipher_data(ctx);
 
     if (EVP_CIPHER_CTX_get_app_data(ctx) == NULL) {
-        EVP_CIPHER_CTX_set_app_data(ctx, EVP_CIPHER_CTX_cipher_data(ctx));
+        EVP_CIPHER_CTX_set_app_data(ctx, EVP_CIPHER_CTX_get_cipher_data(ctx));
     }
 
     if (key != NULL) {
@@ -166,26 +206,26 @@ static int gost_grasshopper_cipher_init(EVP_CIPHER_CTX* ctx, const unsigned char
     return 1;
 }
 
-static GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_ecb(EVP_CIPHER_CTX* ctx, const unsigned char* key,
+GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_ecb(EVP_CIPHER_CTX* ctx, const unsigned char* key,
                                                                const unsigned char* iv,
                                                                int enc) {
-    gost_grasshopper_cipher_ctx* c = EVP_CIPHER_CTX_cipher_data(ctx);
+    gost_grasshopper_cipher_ctx* c = EVP_CIPHER_CTX_get_cipher_data(ctx);
     c->type = GRASSHOPPER_CIPHER_ECB;
     return gost_grasshopper_cipher_init(ctx, key, iv, enc);
 }
 
-static GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_cbc(EVP_CIPHER_CTX* ctx, const unsigned char* key,
+GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_cbc(EVP_CIPHER_CTX* ctx, const unsigned char* key,
                                                                const unsigned char* iv,
                                                                int enc) {
-    gost_grasshopper_cipher_ctx* c = EVP_CIPHER_CTX_cipher_data(ctx);
+    gost_grasshopper_cipher_ctx* c = EVP_CIPHER_CTX_get_cipher_data(ctx);
     c->type = GRASSHOPPER_CIPHER_CBC;
     return gost_grasshopper_cipher_init(ctx, key, iv, enc);
 }
 
-static GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_ofb(EVP_CIPHER_CTX* ctx, const unsigned char* key,
+GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_ofb(EVP_CIPHER_CTX* ctx, const unsigned char* key,
                                                                const unsigned char* iv,
                                                                int enc) {
-    gost_grasshopper_cipher_ctx_ofb* c = EVP_CIPHER_CTX_cipher_data(ctx);
+    gost_grasshopper_cipher_ctx_ofb* c = EVP_CIPHER_CTX_get_cipher_data(ctx);
 
     c->c.type = GRASSHOPPER_CIPHER_OFB;
 
@@ -194,40 +234,51 @@ static GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_ofb(EVP_CIPHER_CTX* c
     return gost_grasshopper_cipher_init(ctx, key, iv, enc);
 }
 
-static GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_cfb(EVP_CIPHER_CTX* ctx, const unsigned char* key,
+GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_cfb(EVP_CIPHER_CTX* ctx, const unsigned char* key,
                                                                const unsigned char* iv,
                                                                int enc) {
-    gost_grasshopper_cipher_ctx* c = EVP_CIPHER_CTX_cipher_data(ctx);
+    gost_grasshopper_cipher_ctx* c = EVP_CIPHER_CTX_get_cipher_data(ctx);
     c->type = GRASSHOPPER_CIPHER_CFB;
     return gost_grasshopper_cipher_init(ctx, key, iv, enc);
 }
 
-static GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_ctr(EVP_CIPHER_CTX* ctx, const unsigned char* key,
+GRASSHOPPER_INLINE int gost_grasshopper_cipher_init_ctr(EVP_CIPHER_CTX* ctx, const unsigned char* key,
                                                                const unsigned char* iv,
                                                                int enc) {
-    gost_grasshopper_cipher_ctx_ctr* c = EVP_CIPHER_CTX_cipher_data(ctx);
+    gost_grasshopper_cipher_ctx_ctr* c = EVP_CIPHER_CTX_get_cipher_data(ctx);
 
     c->c.type = GRASSHOPPER_CIPHER_CTR;
+    EVP_CIPHER_CTX_set_num(ctx, 0);
 
-    grasshopper_zero128(&c->iv_buffer);
     grasshopper_zero128(&c->partial_buffer);
 
-    c->counter = 0;
+    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);
 }
 
-static GRASSHOPPER_INLINE int gost_grasshopper_cipher_do(EVP_CIPHER_CTX* ctx, unsigned char* out,
+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_cipher_data(ctx);
+    gost_grasshopper_cipher_ctx* c = (gost_grasshopper_cipher_ctx*) EVP_CIPHER_CTX_get_cipher_data(ctx);
     struct GRASSHOPPER_CIPHER_PARAMS* params = &gost_cipher_params[c->type];
 
     return params->do_cipher(ctx, out, in, inl);
 }
 
-static int gost_grasshopper_cipher_do_ecb(EVP_CIPHER_CTX* ctx, unsigned char* out,
+int gost_grasshopper_cipher_do_ecb(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_cipher_data(ctx);
+    gost_grasshopper_cipher_ctx* c = (gost_grasshopper_cipher_ctx*) EVP_CIPHER_CTX_get_cipher_data(ctx);
     bool encrypting = (bool) EVP_CIPHER_CTX_encrypting(ctx);
     const unsigned char* current_in = in;
     unsigned char* current_out = out;
@@ -249,9 +300,9 @@ static int gost_grasshopper_cipher_do_ecb(EVP_CIPHER_CTX* ctx, unsigned char* ou
     return 1;
 }
 
-static int gost_grasshopper_cipher_do_cbc(EVP_CIPHER_CTX* ctx, unsigned char* out,
+int gost_grasshopper_cipher_do_cbc(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_cipher_data(ctx);
+    gost_grasshopper_cipher_ctx* c = (gost_grasshopper_cipher_ctx*) EVP_CIPHER_CTX_get_cipher_data(ctx);
     unsigned char* iv = EVP_CIPHER_CTX_iv_noconst(ctx);
     bool encrypting = (bool) EVP_CIPHER_CTX_encrypting(ctx);
     const unsigned char* current_in = in;
@@ -281,27 +332,57 @@ static int gost_grasshopper_cipher_do_cbc(EVP_CIPHER_CTX* ctx, unsigned char* ou
     return 1;
 }
 
-static int gost_grasshopper_cipher_do_ctr(EVP_CIPHER_CTX* ctx, unsigned char* out,
+void inc_counter(unsigned char* counter, size_t counter_bytes)
+{
+    unsigned char c;
+    unsigned int n = counter_bytes;
+
+    do {
+        --n;
+        c = counter[n];
+        ++c;
+        counter[n] = c;
+        if (c) return;
+    } while (n);
+}
+
+/* increment counter (128-bit int) by 1 */
+static void ctr128_inc(unsigned char *counter)
+{
+       inc_counter(counter, 16);
+}
+
+int gost_grasshopper_cipher_do_ctr(EVP_CIPHER_CTX* ctx, unsigned char* out,
                                           const unsigned char* in, size_t inl) {
-    gost_grasshopper_cipher_ctx_ctr* c = (gost_grasshopper_cipher_ctx_ctr*) EVP_CIPHER_CTX_cipher_data(ctx);
+    gost_grasshopper_cipher_ctx_ctr* c = (gost_grasshopper_cipher_ctx_ctr*) EVP_CIPHER_CTX_get_cipher_data(ctx);
     unsigned char* iv = EVP_CIPHER_CTX_iv_noconst(ctx);
     const unsigned char* current_in = in;
     unsigned char* current_out = out;
-    size_t blocks = inl / GRASSHOPPER_BLOCK_SIZE;
     grasshopper_w128_t* currentInputBlock;
     grasshopper_w128_t* currentOutputBlock;
+    unsigned int n = EVP_CIPHER_CTX_num(ctx);
     size_t lasted;
+    size_t i;
+
+    while (n && inl) {
+       *(current_out++) = *(current_in++) ^ c->partial_buffer.b[n];
+       --inl;
+       n = (n + 1) % GRASSHOPPER_BLOCK_SIZE;
+    }
+    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 (size_t i = 0; i < blocks; i++, current_in += GRASSHOPPER_BLOCK_SIZE, current_out += GRASSHOPPER_BLOCK_SIZE) {
+    for (i = 0; i < blocks; i++) {
         currentInputBlock = (grasshopper_w128_t*) current_in;
         currentOutputBlock = (grasshopper_w128_t*) current_out;
-        memcpy(c->iv_buffer.b + 8, &c->counter, 8);
-        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);
-        c->counter += 1;
+        ctr128_inc(iv_buffer->b);
+        current_in += GRASSHOPPER_BLOCK_SIZE;
+        current_out += GRASSHOPPER_BLOCK_SIZE;
     }
 
     // last part
@@ -309,67 +390,84 @@ static int gost_grasshopper_cipher_do_ctr(EVP_CIPHER_CTX* ctx, unsigned char* ou
     if (lasted > 0) {
         currentInputBlock = (grasshopper_w128_t*) current_in;
         currentOutputBlock = (grasshopper_w128_t*) current_out;
-        memcpy(c->iv_buffer.b + 8, &c->counter, 8);
-        grasshopper_encrypt_block(&c->c.encrypt_round_keys, &c->iv_buffer, &c->partial_buffer, &c->c.buffer);
-        for (size_t i = 0; i < lasted; i++) {
+        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];
         }
-        c->counter += 1;
+       EVP_CIPHER_CTX_set_num(ctx, i);
+        ctr128_inc(iv_buffer->b);
     }
 
     return 1;
 }
 
-static void gost_grasshopper_cnt_next(gost_grasshopper_cipher_ctx_ofb* ctx, grasshopper_w128_t* iv,
-                                      grasshopper_w128_t* buf) {
-    memcpy(&ctx->buffer1, iv, 16);
-    ctx->g = ctx->buffer1.b[0] | (ctx->buffer1.b[1] << 8) | (ctx->buffer1.b[2] << 16) |
-             ((uint32_t) ctx->buffer1.b[3] << 24);
-    ctx->g += 0x01010101;
-    ctx->buffer1.b[0] = (unsigned char) (ctx->g & 0xff);
-    ctx->buffer1.b[1] = (unsigned char) ((ctx->g >> 8) & 0xff);
-    ctx->buffer1.b[2] = (unsigned char) ((ctx->g >> 16) & 0xff);
-    ctx->buffer1.b[3] = (unsigned char) ((ctx->g >> 24) & 0xff);
-    ctx->g = ctx->buffer1.b[4] | (ctx->buffer1.b[5] << 8) | (ctx->buffer1.b[6] << 16) |
-             ((uint32_t) ctx->buffer1.b[7] << 24);
-    ctx->go = ctx->g;
-    ctx->g += 0x01010104;
-    if (ctx->go > ctx->g) {                 /* overflow */
-        ctx->g++;
+#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++;
     }
-    ctx->buffer1.b[4] = (unsigned char) (ctx->g & 0xff);
-    ctx->buffer1.b[5] = (unsigned char) ((ctx->g >> 8) & 0xff);
-    ctx->buffer1.b[6] = (unsigned char) ((ctx->g >> 16) & 0xff);
-    ctx->buffer1.b[7] = (unsigned char) ((ctx->g >> 24) & 0xff);
-    ctx->g = ctx->buffer1.b[8] | (ctx->buffer1.b[9] << 8) | (ctx->buffer1.b[10] << 16) |
-             ((uint32_t) ctx->buffer1.b[11] << 24);
-    ctx->go = ctx->g;
-    ctx->g += 0x01010107;
-    if (ctx->go > ctx->g) {                 /* overflow */
-        ctx->g++;
+    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;
     }
-    ctx->buffer1.b[8] = (unsigned char) (ctx->g & 0xff);
-    ctx->buffer1.b[9] = (unsigned char) ((ctx->g >> 8) & 0xff);
-    ctx->buffer1.b[10] = (unsigned char) ((ctx->g >> 16) & 0xff);
-    ctx->buffer1.b[11] = (unsigned char) ((ctx->g >> 24) & 0xff);
-    ctx->g = ctx->buffer1.b[12] | (ctx->buffer1.b[13] << 8) | (ctx->buffer1.b[14] << 16) |
-             ((uint32_t) ctx->buffer1.b[15] << 24);
-    ctx->go = ctx->g;
-    ctx->g += 0x01010110;
-    if (ctx->go > ctx->g) {                 /* overflow */
-        ctx->g++;
+
+    // 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;
     }
-    ctx->buffer1.b[12] = (unsigned char) (ctx->g & 0xff);
-    ctx->buffer1.b[13] = (unsigned char) ((ctx->g >> 8) & 0xff);
-    ctx->buffer1.b[14] = (unsigned char) ((ctx->g >> 16) & 0xff);
-    ctx->buffer1.b[15] = (unsigned char) ((ctx->g >> 24) & 0xff);
-    memcpy(iv, &ctx->buffer1, 16);
+    EVP_CIPHER_CTX_set_num(ctx, num);
+
+    return 1;
+}
+
+/*
+ * Fixed 128-bit IV implementation make shift regiser redundant.
+ */
+static void gost_grasshopper_cnt_next(gost_grasshopper_cipher_ctx_ofb* ctx, grasshopper_w128_t* iv,
+                                      grasshopper_w128_t* buf) {
+    memcpy(&ctx->buffer1, iv, 16);
     grasshopper_encrypt_block(&ctx->c.encrypt_round_keys, &ctx->buffer1, buf, &ctx->c.buffer);
+    memcpy(iv, buf, 16);
 }
 
-static int gost_grasshopper_cipher_do_ofb(EVP_CIPHER_CTX* ctx, unsigned char* out,
+int gost_grasshopper_cipher_do_ofb(EVP_CIPHER_CTX* ctx, unsigned char* out,
                                           const unsigned char* in, size_t inl) {
-    gost_grasshopper_cipher_ctx_ofb* c = (gost_grasshopper_cipher_ctx_ofb*) EVP_CIPHER_CTX_cipher_data(ctx);
+    gost_grasshopper_cipher_ctx_ofb* c = (gost_grasshopper_cipher_ctx_ofb*) EVP_CIPHER_CTX_get_cipher_data(ctx);
     const unsigned char* in_ptr = in;
     unsigned char* out_ptr = out;
     unsigned char* buf = EVP_CIPHER_CTX_buf_noconst(ctx);
@@ -425,9 +523,9 @@ static int gost_grasshopper_cipher_do_ofb(EVP_CIPHER_CTX* ctx, unsigned char* ou
     return 1;
 }
 
-static int gost_grasshopper_cipher_do_cfb(EVP_CIPHER_CTX* ctx, unsigned char* out,
+int gost_grasshopper_cipher_do_cfb(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_cipher_data(ctx);
+    gost_grasshopper_cipher_ctx* c = (gost_grasshopper_cipher_ctx*) EVP_CIPHER_CTX_get_cipher_data(ctx);
     const unsigned char* in_ptr = in;
     unsigned char* out_ptr = out;
     unsigned char* buf = EVP_CIPHER_CTX_buf_noconst(ctx);
@@ -504,8 +602,8 @@ static int gost_grasshopper_cipher_do_cfb(EVP_CIPHER_CTX* ctx, unsigned char* ou
     return 1;
 }
 
-static int gost_grasshopper_cipher_cleanup(EVP_CIPHER_CTX* ctx) {
-    gost_grasshopper_cipher_ctx* c = (gost_grasshopper_cipher_ctx*) EVP_CIPHER_CTX_cipher_data(ctx);
+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);
     struct GRASSHOPPER_CIPHER_PARAMS* params = &gost_cipher_params[c->type];
 
     gost_grasshopper_cipher_destroy(c);
@@ -518,17 +616,16 @@ static int gost_grasshopper_cipher_cleanup(EVP_CIPHER_CTX* ctx) {
     return 1;
 }
 
-static int gost_grasshopper_set_asn1_parameters(EVP_CIPHER_CTX* ctx, ASN1_TYPE* params) {
+int gost_grasshopper_set_asn1_parameters(EVP_CIPHER_CTX* ctx, ASN1_TYPE* params) {
     int len = 0;
     unsigned char* buf = NULL;
-    unsigned char* p = NULL;
     ASN1_OCTET_STRING* os = NULL;
 
     os = ASN1_OCTET_STRING_new();
 
     if (!os || !ASN1_OCTET_STRING_set(os, buf, len)) {
         OPENSSL_free(buf);
-        GOSTerr(GOST_F_GOST89_SET_ASN1_PARAMETERS, ERR_R_MALLOC_FAILURE);
+        GOSTerr(GOST_F_GOST_GRASSHOPPER_SET_ASN1_PARAMETERS, ERR_R_MALLOC_FAILURE);
         return 0;
     }
     OPENSSL_free(buf);
@@ -537,7 +634,7 @@ static int gost_grasshopper_set_asn1_parameters(EVP_CIPHER_CTX* ctx, ASN1_TYPE*
     return 1;
 }
 
-static GRASSHOPPER_INLINE int gost_grasshopper_get_asn1_parameters(EVP_CIPHER_CTX* ctx, ASN1_TYPE* params) {
+GRASSHOPPER_INLINE int gost_grasshopper_get_asn1_parameters(EVP_CIPHER_CTX* ctx, ASN1_TYPE* params) {
     int ret = -1;
 
     if (ASN1_TYPE_get(params) != V_ASN1_SEQUENCE) {
@@ -547,23 +644,31 @@ static GRASSHOPPER_INLINE int gost_grasshopper_get_asn1_parameters(EVP_CIPHER_CT
     return 1;
 }
 
-static int gost_grasshopper_cipher_ctl(EVP_CIPHER_CTX* ctx, int type, int arg, void* ptr) {
+int gost_grasshopper_cipher_ctl(EVP_CIPHER_CTX* ctx, int type, int arg, void* ptr) {
     switch (type) {
         case EVP_CTRL_RAND_KEY: {
             if (RAND_bytes((unsigned char*) ptr, EVP_CIPHER_CTX_key_length(ctx)) <= 0) {
-                GOSTerr(GOST_F_GOST_CIPHER_CTL, GOST_R_RNG_ERROR);
+                GOSTerr(GOST_F_GOST_GRASSHOPPER_CIPHER_CTL, GOST_R_RNG_ERROR);
                 return -1;
             }
             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_CIPHER_CTL, GOST_R_UNSUPPORTED_CIPHER_CTL_COMMAND);
+            GOSTerr(GOST_F_GOST_GRASSHOPPER_CIPHER_CTL, GOST_R_UNSUPPORTED_CIPHER_CTL_COMMAND);
             return -1;
     }
     return 1;
 }
 
-static GRASSHOPPER_INLINE EVP_CIPHER* cipher_gost_grasshopper_create(int cipher_type, int block_size) {
+GRASSHOPPER_INLINE EVP_CIPHER* cipher_gost_grasshopper_create(int cipher_type, int block_size) {
     return EVP_CIPHER_meth_new(cipher_type,
                                block_size  /* block_size */,
                                GRASSHOPPER_KEY_SIZE /* key_size */);
@@ -585,7 +690,7 @@ const int cipher_gost_grasshopper_setup(EVP_CIPHER* cipher, uint8_t mode, int iv
            EVP_CIPHER_meth_set_do_cipher(cipher, gost_grasshopper_cipher_do);
 }
 
-static const GRASSHOPPER_INLINE EVP_CIPHER* cipher_gost_grasshopper(uint8_t mode, uint8_t num) {
+const GRASSHOPPER_INLINE EVP_CIPHER* cipher_gost_grasshopper(uint8_t mode, uint8_t num) {
     EVP_CIPHER** cipher;
     struct GRASSHOPPER_CIPHER_PARAMS* params;
 
@@ -637,6 +742,26 @@ const GRASSHOPPER_INLINE EVP_CIPHER* cipher_gost_grasshopper_ctr() {
     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_ECB] = NULL;
+    EVP_CIPHER_meth_free(gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_CBC]);
+    gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_CBC] = NULL;
+    EVP_CIPHER_meth_free(gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_OFB]);
+    gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_OFB] = NULL;
+    EVP_CIPHER_meth_free(gost_grasshopper_ciphers[GRASSHOPPER_CIPHER_CFB]);
+    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)
 }
 #endif