+ if(enc && (enc != -1)) enc = 1;
+ /* Whether it's nice or not, "Inits" can be used on "Final"'d contexts
+ * so this context may already have an ENGINE! Try to avoid releasing
+ * the previous handle, re-querying for an ENGINE, and having a
+ * reinitialisation, when it may all be unecessary. */
+ if (ctx->engine && ctx->cipher && (!cipher ||
+ (cipher && (cipher->nid == ctx->cipher->nid))))
+ goto skip_to_init;
+ if (cipher)
+ {
+ /* Ensure an ENGINE left lying around from last time is cleared
+ * (the previous check attempted to avoid this if the same
+ * ENGINE and EVP_CIPHER could be used). */
+ if(ctx->engine)
+ ENGINE_finish(ctx->engine);
+ if(!impl)
+ /* Ask if an ENGINE is reserved for this job */
+ impl = ENGINE_get_cipher_engine(cipher->nid);
+ if(impl)
+ {
+ /* There's an ENGINE for this job ... (apparently) */
+ const EVP_CIPHER *c = ENGINE_get_cipher(impl, cipher->nid);
+ if(!c)
+ {
+ /* One positive side-effect of US's export
+ * control history, is that we should at least
+ * be able to avoid using US mispellings of
+ * "initialisation"? */
+ EVPerr(EVP_F_EVP_CIPHERINIT, EVP_R_INITIALIZATION_ERROR);
+ return 0;
+ }
+ /* We'll use the ENGINE's private cipher definition */
+ cipher = c;
+ /* Store the ENGINE functional reference so we know
+ * 'cipher' came from an ENGINE and we need to release
+ * it when done. */
+ ctx->engine = impl;
+ }
+ else
+ ctx->engine = NULL;