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Diffstat (limited to 'openssl-1.1.0h/crypto/des/ofb_enc.c')
-rw-r--r--openssl-1.1.0h/crypto/des/ofb_enc.c82
1 files changed, 82 insertions, 0 deletions
diff --git a/openssl-1.1.0h/crypto/des/ofb_enc.c b/openssl-1.1.0h/crypto/des/ofb_enc.c
new file mode 100644
index 0000000..65a9b86
--- /dev/null
+++ b/openssl-1.1.0h/crypto/des/ofb_enc.c
@@ -0,0 +1,82 @@
+/*
+ * Copyright 1995-2016 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 "des_locl.h"
+
+/*
+ * The input and output are loaded in multiples of 8 bits. What this means is
+ * that if you have numbits=12 and length=2 the first 12 bits will be
+ * retrieved from the first byte and half the second. The second 12 bits
+ * will come from the 3rd and half the 4th byte.
+ */
+void DES_ofb_encrypt(const unsigned char *in, unsigned char *out, int numbits,
+ long length, DES_key_schedule *schedule,
+ DES_cblock *ivec)
+{
+ register DES_LONG d0, d1, vv0, vv1, v0, v1, n = (numbits + 7) / 8;
+ register DES_LONG mask0, mask1;
+ register long l = length;
+ register int num = numbits;
+ DES_LONG ti[2];
+ unsigned char *iv;
+
+ if (num > 64)
+ return;
+ if (num > 32) {
+ mask0 = 0xffffffffL;
+ if (num >= 64)
+ mask1 = mask0;
+ else
+ mask1 = (1L << (num - 32)) - 1;
+ } else {
+ if (num == 32)
+ mask0 = 0xffffffffL;
+ else
+ mask0 = (1L << num) - 1;
+ mask1 = 0x00000000L;
+ }
+
+ iv = &(*ivec)[0];
+ c2l(iv, v0);
+ c2l(iv, v1);
+ ti[0] = v0;
+ ti[1] = v1;
+ while (l-- > 0) {
+ ti[0] = v0;
+ ti[1] = v1;
+ DES_encrypt1((DES_LONG *)ti, schedule, DES_ENCRYPT);
+ vv0 = ti[0];
+ vv1 = ti[1];
+ c2ln(in, d0, d1, n);
+ in += n;
+ d0 = (d0 ^ vv0) & mask0;
+ d1 = (d1 ^ vv1) & mask1;
+ l2cn(d0, d1, out, n);
+ out += n;
+
+ if (num == 32) {
+ v0 = v1;
+ v1 = vv0;
+ } else if (num == 64) {
+ v0 = vv0;
+ v1 = vv1;
+ } else if (num > 32) { /* && num != 64 */
+ v0 = ((v1 >> (num - 32)) | (vv0 << (64 - num))) & 0xffffffffL;
+ v1 = ((vv0 >> (num - 32)) | (vv1 << (64 - num))) & 0xffffffffL;
+ } else { /* num < 32 */
+
+ v0 = ((v0 >> num) | (v1 << (32 - num))) & 0xffffffffL;
+ v1 = ((v1 >> num) | (vv0 << (32 - num))) & 0xffffffffL;
+ }
+ }
+ iv = &(*ivec)[0];
+ l2c(v0, iv);
+ l2c(v1, iv);
+ v0 = v1 = d0 = d1 = ti[0] = ti[1] = vv0 = vv1 = 0;
+}