+ if(enc && (enc != -1)) enc = 1;
+ if (cipher)
+ {
+ if(ctx->cipher)
+ EVP_CIPHER_CTX_cleanup(ctx);
+ ctx->cipher=cipher;
+ ctx->cipher_data=OPENSSL_malloc(ctx->cipher->ctx_size);
+ ctx->key_len = cipher->key_len;
+ ctx->flags = 0;
+ if(ctx->cipher->flags & EVP_CIPH_CTRL_INIT) {
+ if(!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_INIT, 0, NULL)) {
+ EVPerr(EVP_F_EVP_CIPHERINIT, EVP_R_INITIALIZATION_ERROR);
+ return 0;
+ }
+ }
+ } else if(!ctx->cipher) {
+ EVPerr(EVP_F_EVP_CIPHERINIT, EVP_R_NO_CIPHER_SET);
+ return 0;
+ }
+
+ /* we assume block size is a power of 2 in *cryptUpdate */
+ assert(ctx->cipher->block_size == 1
+ || ctx->cipher->block_size == 8
+ || ctx->cipher->block_size == 16);
+
+ if(!(EVP_CIPHER_CTX_flags(ctx) & EVP_CIPH_CUSTOM_IV)) {
+ switch(EVP_CIPHER_CTX_mode(ctx)) {
+
+ case EVP_CIPH_STREAM_CIPHER:
+ case EVP_CIPH_ECB_MODE:
+ break;
+
+ case EVP_CIPH_CFB_MODE:
+ case EVP_CIPH_OFB_MODE:
+
+ ctx->num = 0;
+
+ case EVP_CIPH_CBC_MODE:
+
+ if(iv) memcpy(ctx->oiv, iv, EVP_CIPHER_CTX_iv_length(ctx));
+ memcpy(ctx->iv, ctx->oiv, EVP_CIPHER_CTX_iv_length(ctx));
+ break;
+
+ default:
+ return 0;
+ break;
+ }
+ }
+
+ if(key || (ctx->cipher->flags & EVP_CIPH_ALWAYS_CALL_INIT)) {
+ if(!ctx->cipher->init(ctx,key,iv,enc)) return 0;
+ }
+ if(enc != -1) ctx->encrypt=enc;
+ ctx->buf_len=0;
+ ctx->final_used=0;
+ ctx->block_mask=ctx->cipher->block_size-1;
+ return 1;