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-rw-r--r--openssl-1.1.0h/crypto/modes/ofb128.c74
1 files changed, 74 insertions, 0 deletions
diff --git a/openssl-1.1.0h/crypto/modes/ofb128.c b/openssl-1.1.0h/crypto/modes/ofb128.c
new file mode 100644
index 0000000..8309256
--- /dev/null
+++ b/openssl-1.1.0h/crypto/modes/ofb128.c
@@ -0,0 +1,74 @@
+/*
+ * Copyright 2008-2016 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL license (the "License"). You may not use
+ * this file except in compliance with the License. You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#include <openssl/crypto.h>
+#include "modes_lcl.h"
+#include <string.h>
+
+/*
+ * The input and output encrypted as though 128bit ofb mode is being used.
+ * The extra state information to record how much of the 128bit block we have
+ * used is contained in *num;
+ */
+void CRYPTO_ofb128_encrypt(const unsigned char *in, unsigned char *out,
+ size_t len, const void *key,
+ unsigned char ivec[16], int *num, block128_f block)
+{
+ unsigned int n;
+ size_t l = 0;
+
+ n = *num;
+
+#if !defined(OPENSSL_SMALL_FOOTPRINT)
+ if (16 % sizeof(size_t) == 0) { /* always true actually */
+ do {
+ while (n && len) {
+ *(out++) = *(in++) ^ ivec[n];
+ --len;
+ n = (n + 1) % 16;
+ }
+# if defined(STRICT_ALIGNMENT)
+ if (((size_t)in | (size_t)out | (size_t)ivec) % sizeof(size_t) !=
+ 0)
+ break;
+# endif
+ while (len >= 16) {
+ (*block) (ivec, ivec, key);
+ for (; n < 16; n += sizeof(size_t))
+ *(size_t *)(out + n) =
+ *(size_t *)(in + n) ^ *(size_t *)(ivec + n);
+ len -= 16;
+ out += 16;
+ in += 16;
+ n = 0;
+ }
+ if (len) {
+ (*block) (ivec, ivec, key);
+ while (len--) {
+ out[n] = in[n] ^ ivec[n];
+ ++n;
+ }
+ }
+ *num = n;
+ return;
+ } while (0);
+ }
+ /* the rest would be commonly eliminated by x86* compiler */
+#endif
+ while (l < len) {
+ if (n == 0) {
+ (*block) (ivec, ivec, key);
+ }
+ out[l] = in[l] ^ ivec[n];
+ ++l;
+ n = (n + 1) % 16;
+ }
+
+ *num = n;
+}