c->section_size = arg;
break;
}
-#ifdef EVP_CTRL_TLS1_2_TLSTREE
- case EVP_CTRL_TLS1_2_TLSTREE:
+ case EVP_CTRL_TLSTREE:
{
unsigned char newkey[32];
int mode = EVP_CIPHER_CTX_mode(ctx);
- static const unsigned char zeroseq[8];
gost_grasshopper_cipher_ctx_ctr *ctr_ctx = NULL;
gost_grasshopper_cipher_ctx *c = NULL;
unsigned char adjusted_iv[16];
unsigned char seq[8];
- int j, carry;
+ int j, carry, decrement_arg;
if (mode != EVP_CIPH_CTR_MODE)
- return -1;
+ return -1;
ctr_ctx = (gost_grasshopper_cipher_ctx_ctr *)
- EVP_CIPHER_CTX_get_cipher_data(ctx);
+ EVP_CIPHER_CTX_get_cipher_data(ctx);
c = &(ctr_ctx->c);
+ /*
+ * 'arg' parameter indicates what we should do with sequence value.
+ *
+ * When function called, seq is incremented after MAC calculation.
+ * In ETM mode, we use seq 'as is' in the ctrl-function (arg = 0)
+ * Otherwise we have to decrease it in the implementation (arg = 1).
+ */
memcpy(seq, ptr, 8);
- if (EVP_CIPHER_CTX_encrypting(ctx)) {
- /*
- * OpenSSL increments seq after mac calculation.
- * As we have Mac-Then-Encrypt, we need decrement it here on encryption
- * to derive the key correctly.
- * */
- if (memcmp(seq, zeroseq, 8) != 0)
- {
- for(j=7; j>=0; j--)
- {
- if (seq[j] != 0) {seq[j]--; break;}
- else seq[j] = 0xFF;
- }
- }
+ decrement_arg = arg;
+ if (!decrement_sequence(seq, decrement_arg))
+ {
+ GOSTerr(GOST_F_GOST_GRASSHOPPER_CIPHER_CTL, GOST_R_CTRL_CALL_FAILED);
+ return -1;
}
+
if (gost_tlstree(NID_grasshopper_cbc, c->master_key.k.b, newkey,
(const unsigned char *)seq) > 0) {
memset(adjusted_iv, 0, 16);
}
}
return -1;
-#endif
#if 0
case EVP_CTRL_AEAD_GET_TAG:
case EVP_CTRL_AEAD_SET_TAG: