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-rw-r--r--third_party/bearssl/src/des_tab_cbcdec.c85
1 files changed, 85 insertions, 0 deletions
diff --git a/third_party/bearssl/src/des_tab_cbcdec.c b/third_party/bearssl/src/des_tab_cbcdec.c
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+++ b/third_party/bearssl/src/des_tab_cbcdec.c
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+/*
+ * Copyright (c) 2016 Thomas Pornin <[email protected]>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining 
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be 
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "inner.h"
+
+/* see bearssl_block.h */
+void
+br_des_tab_cbcdec_init(br_des_tab_cbcdec_keys *ctx,
+	const void *key, size_t len)
+{
+	ctx->vtable = &br_des_tab_cbcdec_vtable;
+	ctx->num_rounds = br_des_tab_keysched(ctx->skey, key, len);
+	if (len == 8) {
+		br_des_rev_skey(ctx->skey);
+	} else {
+		int i;
+
+		for (i = 0; i < 48; i += 2) {
+			uint32_t t;
+
+			t = ctx->skey[i];
+			ctx->skey[i] = ctx->skey[94 - i];
+			ctx->skey[94 - i] = t;
+			t = ctx->skey[i + 1];
+			ctx->skey[i + 1] = ctx->skey[95 - i];
+			ctx->skey[95 - i] = t;
+		}
+	}
+}
+
+/* see bearssl_block.h */
+void
+br_des_tab_cbcdec_run(const br_des_tab_cbcdec_keys *ctx,
+	void *iv, void *data, size_t len)
+{
+	unsigned char *buf, *ivbuf;
+
+	ivbuf = iv;
+	buf = data;
+	while (len > 0) {
+		unsigned char tmp[8];
+		int i;
+
+		memcpy(tmp, buf, 8);
+		br_des_tab_process_block(ctx->num_rounds, ctx->skey, buf);
+		for (i = 0; i < 8; i ++) {
+			buf[i] ^= ivbuf[i];
+		}
+		memcpy(ivbuf, tmp, 8);
+		buf += 8;
+		len -= 8;
+	}
+}
+
+/* see bearssl_block.h */
+const br_block_cbcdec_class br_des_tab_cbcdec_vtable = {
+	sizeof(br_des_tab_cbcdec_keys),
+	8,
+	3,
+	(void (*)(const br_block_cbcdec_class **, const void *, size_t))
+		&br_des_tab_cbcdec_init,
+	(void (*)(const br_block_cbcdec_class *const *, void *, void *, size_t))
+		&br_des_tab_cbcdec_run
+};