Kuznyechik ASN1 parameters parsing

[openssl-gost/engine.git] / gost_grasshopper_cipher.c

diff --git a/gost_grasshopper_cipher.c b/gost_grasshopper_cipher.c
index 2955534cb58fca1bad3b417ec106507a87785b62..75a0408e24b8e39eb073824369f08bd956f73aa3 100644 (file)
--- a/gost_grasshopper_cipher.c
+++ b/gost_grasshopper_cipher.c
@@ -7,6 +7,7 @@
 #include "gost_grasshopper_defines.h"
 #include "gost_grasshopper_math.h"
 #include "gost_grasshopper_core.h"
+#include "gost_gost2015.h"
 
 #include <openssl/evp.h>
 #include <openssl/rand.h>
@@ -91,21 +92,18 @@ static struct GRASSHOPPER_CIPHER_PARAMS gost_cipher_params[6] = {
                                 gost_grasshopper_cipher_destroy_ctr,
                                 1,
                                 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,
+                                8,
                                 false}
     ,
     {
-                                     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}
+                                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),
+                                8,
+                                false}
     ,
 };
 
@@ -331,8 +329,6 @@ int gost_grasshopper_cipher_do_cbc(EVP_CIPHER_CTX *ctx, unsigned char *out,
     bool encrypting = (bool) EVP_CIPHER_CTX_encrypting(ctx);
     const unsigned char *current_in = in;
     unsigned char *current_out = out;
-    grasshopper_w128_t *currentInputBlock;
-    grasshopper_w128_t *currentOutputBlock;
     size_t blocks = inl / GRASSHOPPER_BLOCK_SIZE;
     size_t i;
     grasshopper_w128_t *currentBlock;
@@ -342,8 +338,8 @@ int gost_grasshopper_cipher_do_cbc(EVP_CIPHER_CTX *ctx, unsigned char *out,
     for (i = 0; i < blocks;
          i++, current_in += GRASSHOPPER_BLOCK_SIZE, current_out +=
          GRASSHOPPER_BLOCK_SIZE) {
-        currentInputBlock = (grasshopper_w128_t *) current_in;
-        currentOutputBlock = (grasshopper_w128_t *) current_out;
+        grasshopper_w128_t *currentInputBlock = (grasshopper_w128_t *) current_in;
+        grasshopper_w128_t *currentOutputBlock = (grasshopper_w128_t *) current_out;
         if (encrypting) {
             grasshopper_append128(currentBlock, currentInputBlock);
             grasshopper_encrypt_block(&c->encrypt_round_keys, currentBlock,
@@ -366,10 +362,10 @@ int gost_grasshopper_cipher_do_cbc(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 {
+        unsigned char c;
         --n;
         c = counter[n];
         ++c;
@@ -692,36 +688,37 @@ int gost_grasshopper_cipher_cleanup(EVP_CIPHER_CTX *ctx)
 
 int gost_grasshopper_set_asn1_parameters(EVP_CIPHER_CTX *ctx, ASN1_TYPE *params)
 {
-    int len = 0;
-    unsigned char *buf = NULL;
-    ASN1_OCTET_STRING *os = NULL;
+       if (EVP_CIPHER_CTX_mode(ctx) == EVP_CIPH_CTR_MODE) {
+               gost_grasshopper_cipher_ctx_ctr *ctr = EVP_CIPHER_CTX_get_cipher_data(ctx);
 
-    os = ASN1_OCTET_STRING_new();
-
-    if (!os || !ASN1_OCTET_STRING_set(os, buf, len)) {
-        ASN1_OCTET_STRING_free(os);
-        OPENSSL_free(buf);
-        GOSTerr(GOST_F_GOST_GRASSHOPPER_SET_ASN1_PARAMETERS,
-                ERR_R_MALLOC_FAILURE);
-        return 0;
-    }
-    OPENSSL_free(buf);
-
-    ASN1_TYPE_set(params, V_ASN1_SEQUENCE, os);
-    return 1;
+               return gost2015_set_asn1_params(params, EVP_CIPHER_CTX_original_iv(ctx), 8,
+                               ctr->kdf_seed);
+       }
+       return 0;
 }
 
 GRASSHOPPER_INLINE int gost_grasshopper_get_asn1_parameters(EVP_CIPHER_CTX
                                                             *ctx, ASN1_TYPE
                                                             *params)
 {
-    int ret = -1;
+       if (EVP_CIPHER_CTX_mode(ctx) == EVP_CIPH_CTR_MODE) {
+               gost_grasshopper_cipher_ctx_ctr *ctr = EVP_CIPHER_CTX_get_cipher_data(ctx);
 
-    if (ASN1_TYPE_get(params) != V_ASN1_SEQUENCE) {
-        return ret;
-    }
+               int iv_len = 16;
+               unsigned char iv[16];
 
-    return 1;
+               if (gost2015_get_asn1_params(params, 16, iv, 8, ctr->kdf_seed) == 0) {
+                       return 0;
+               }
+
+               memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), iv, iv_len);
+               memcpy((unsigned char *)EVP_CIPHER_CTX_original_iv(ctx), iv, iv_len);
+
+               /* CMS implies 256kb mesh_section_size */
+               ctr->section_size = 256*1024;
+               return 1;
+       }
+       return 0;
 }
 
 int gost_grasshopper_cipher_ctl(EVP_CIPHER_CTX *ctx, int type, int arg,