1 files changed, 251 insertions, 0 deletions
diff --git a/ext/libressl/crypto/modes/ctr128.c b/ext/libressl/crypto/modes/ctr128.c
new file mode 100644
index 0000000..3f14e4e
--- /dev/null
+++ b/ext/libressl/crypto/modes/ctr128.c
@@ -0,0 +1,251 @@
+/* $OpenBSD: ctr128.c,v 1.7 2017/08/13 17:46:24 bcook Exp $ */
+/* ====================================================================
+ * Copyright (c) 2008 The OpenSSL Project.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. All advertising materials mentioning features or use of this
+ *    software must display the following acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ *    endorse or promote products derived from this software without
+ *    prior written permission. For written permission, please contact
+ *    openssl-core@openssl.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ *    nor may "OpenSSL" appear in their names without prior written
+ *    permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ *    acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ====================================================================
+ *
+ */
+
+#include <openssl/crypto.h>
+#include "modes_lcl.h"
+#include <string.h>
+
+#ifndef MODES_DEBUG
+# ifndef NDEBUG
+#  define NDEBUG
+# endif
+#endif
+#include <assert.h>
+
+/* NOTE: the IV/counter CTR mode is big-endian.  The code itself
+ * is endian-neutral. */
+
+/* increment counter (128-bit int) by 1 */
+static void ctr128_inc(unsigned char *counter) {
+	u32 n=16;
+	u8  c;
+
+	do {
+		--n;
+		c = counter[n];
+		++c;
+		counter[n] = c;
+		if (c) return;
+	} while (n);
+}
+
+#if !defined(OPENSSL_SMALL_FOOTPRINT)
+static void
+ctr128_inc_aligned(unsigned char *counter)
+{
+#if BYTE_ORDER == LITTLE_ENDIAN
+	ctr128_inc(counter);
+#else
+	size_t *data, c, n;
+	data = (size_t *)counter;
+	n = 16 / sizeof(size_t);
+	do {
+		--n;
+		c = data[n];
+		++c;
+		data[n] = c;
+		if (c)
+			return;
+	} while (n);
+#endif
+}
+#endif
+
+/* The input encrypted as though 128bit counter mode is being
+ * used.  The extra state information to record how much of the
+ * 128bit block we have used is contained in *num, and the
+ * encrypted counter is kept in ecount_buf.  Both *num and
+ * ecount_buf must be initialised with zeros before the first
+ * call to CRYPTO_ctr128_encrypt().
+ *
+ * This algorithm assumes that the counter is in the x lower bits
+ * of the IV (ivec), and that the application has full control over
+ * overflow and the rest of the IV.  This implementation takes NO
+ * responsability for checking that the counter doesn't overflow
+ * into the rest of the IV when incremented.
+ */
+void CRYPTO_ctr128_encrypt(const unsigned char *in, unsigned char *out,
+			size_t len, const void *key,
+			unsigned char ivec[16], unsigned char ecount_buf[16],
+			unsigned int *num, block128_f block)
+{
+	unsigned int n;
+	size_t l=0;
+
+	assert(*num < 16);
+
+	n = *num;
+
+#if !defined(OPENSSL_SMALL_FOOTPRINT)
+	if (16%sizeof(size_t) == 0) do { /* always true actually */
+		while (n && len) {
+			*(out++) = *(in++) ^ ecount_buf[n];
+			--len;
+			n = (n+1) % 16;
+		}
+
+#ifdef __STRICT_ALIGNMENT
+		if (((size_t)in|(size_t)out|(size_t)ivec)%sizeof(size_t) != 0)
+			break;
+#endif
+		while (len>=16) {
+			(*block)(ivec, ecount_buf, key);
+			ctr128_inc_aligned(ivec);
+			for (; n<16; n+=sizeof(size_t))
+				*(size_t *)(out+n) =
+				*(size_t *)(in+n) ^ *(size_t *)(ecount_buf+n);
+			len -= 16;
+			out += 16;
+			in  += 16;
+			n = 0;
+		}
+		if (len) {
+			(*block)(ivec, ecount_buf, key);
+ 			ctr128_inc_aligned(ivec);
+			while (len--) {
+				out[n] = in[n] ^ ecount_buf[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, ecount_buf, key);
+ 			ctr128_inc(ivec);
+		}
+		out[l] = in[l] ^ ecount_buf[n];
+		++l;
+		n = (n+1) % 16;
+	}
+
+	*num=n;
+}
+
+/* increment upper 96 bits of 128-bit counter by 1 */
+static void ctr96_inc(unsigned char *counter) {
+	u32 n=12;
+	u8  c;
+
+	do {
+		--n;
+		c = counter[n];
+		++c;
+		counter[n] = c;
+		if (c) return;
+	} while (n);
+}
+
+void CRYPTO_ctr128_encrypt_ctr32(const unsigned char *in, unsigned char *out,
+			size_t len, const void *key,
+			unsigned char ivec[16], unsigned char ecount_buf[16],
+			unsigned int *num, ctr128_f func)
+{
+	unsigned int n,ctr32;
+
+	assert(*num < 16);
+
+	n = *num;
+
+	while (n && len) {
+		*(out++) = *(in++) ^ ecount_buf[n];
+		--len;
+		n = (n+1) % 16;
+	}
+
+	ctr32 = GETU32(ivec+12);
+	while (len>=16) {
+		size_t blocks = len/16;
+		/*
+		 * 1<<28 is just a not-so-small yet not-so-large number...
+		 * Below condition is practically never met, but it has to
+		 * be checked for code correctness.
+		 */
+		if (sizeof(size_t)>sizeof(unsigned int) && blocks>(1U<<28))
+			blocks = (1U<<28);
+		/*
+		 * As (*func) operates on 32-bit counter, caller
+		 * has to handle overflow. 'if' below detects the
+		 * overflow, which is then handled by limiting the
+		 * amount of blocks to the exact overflow point...
+		 */
+		ctr32 += (u32)blocks;
+		if (ctr32 < blocks) {
+			blocks -= ctr32;
+			ctr32   = 0;
+		}
+		(*func)(in,out,blocks,key,ivec);
+		/* (*ctr) does not update ivec, caller does: */
+		PUTU32(ivec+12,ctr32);
+		/* ... overflow was detected, propogate carry. */
+		if (ctr32 == 0)	ctr96_inc(ivec);
+		blocks *= 16;
+		len -= blocks;
+		out += blocks;
+		in  += blocks;
+	}
+	if (len) {
+		memset(ecount_buf,0,16);
+		(*func)(ecount_buf,ecount_buf,1,key,ivec);
+		++ctr32;
+		PUTU32(ivec+12,ctr32);
+		if (ctr32 == 0)	ctr96_inc(ivec);
+		while (len--) {
+			out[n] = in[n] ^ ecount_buf[n];
+			++n;
+		}
+	}
+
+	*num=n;
+}