--- old/usr/src/cmd/ssh/libssh/common/deattack.c	Tue Aug 16 19:27:13 2016
+++ /dev/null	Tue Aug 16 19:26:53 2016
@@ -1,178 +0,0 @@
-/*
- * Cryptographic attack detector for ssh - source code
- *
- * Copyright (c) 1998 CORE SDI S.A., Buenos Aires, Argentina.
- *
- * All rights reserved. Redistribution and use in source and binary
- * forms, with or without modification, are permitted provided that
- * this copyright notice is retained.
- *
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
- * WARRANTIES ARE DISCLAIMED. IN NO EVENT SHALL CORE SDI S.A. BE
- * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY OR
- * CONSEQUENTIAL DAMAGES RESULTING FROM THE USE OR MISUSE OF THIS
- * SOFTWARE.
- *
- * Ariel Futoransky <futo@core-sdi.com>
- * <http://www.core-sdi.com>
- */
-
-#include "includes.h"
-RCSID("$OpenBSD: deattack.c,v 1.18 2002/03/04 17:27:39 stevesk Exp $");
-
-#pragma ident	"%Z%%M%	%I%	%E% SMI"
-
-#include "deattack.h"
-#include "log.h"
-#include "crc32.h"
-#include "getput.h"
-#include "xmalloc.h"
-#include "deattack.h"
-
-/*
- * CRC attack detection has a worst-case behaviour that is O(N^2) over
- * the number of identical blocks in a packet. This behaviour can be 
- * exploited to create a limited denial of service attack. 
- * 
- * However, because we are dealing with encrypted data, identical
- * blocks should only occur every 2^35 maximally-sized packets or so. 
- * Consequently, we can detect this DoS by looking for identical blocks
- * in a packet.
- *
- * The parameter below determines how many identical blocks we will
- * accept in a single packet, trading off between attack detection and
- * likelihood of terminating a legitimate connection. A value of 32 
- * corresponds to an average of 2^40 messages before an attack is
- * misdetected
- */
-#define MAX_IDENTICAL	32
-
-/* SSH Constants */
-#define SSH_MAXBLOCKS	(32 * 1024)
-#define SSH_BLOCKSIZE	(8)
-
-/* Hashing constants */
-#define HASH_MINSIZE	(8 * 1024)
-#define HASH_ENTRYSIZE	(2)
-#define HASH_FACTOR(x)	((x)*3/2)
-#define HASH_UNUSEDCHAR	(0xff)
-#define HASH_UNUSED	(0xffff)
-#define HASH_IV		(0xfffe)
-
-#define HASH_MINBLOCKS	(7*SSH_BLOCKSIZE)
-
-
-/* Hash function (Input keys are cipher results) */
-#define HASH(x)		GET_32BIT(x)
-
-#define CMP(a, b)	(memcmp(a, b, SSH_BLOCKSIZE))
-
-static void
-crc_update(u_int32_t *a, u_int32_t b)
-{
-	b ^= *a;
-	*a = ssh_crc32((u_char *) &b, sizeof(b));
-}
-
-/* detect if a block is used in a particular pattern */
-static int
-check_crc(u_char *S, u_char *buf, u_int32_t len,
-	  u_char *IV)
-{
-	u_int32_t crc;
-	u_char *c;
-
-	crc = 0;
-	if (IV && !CMP(S, IV)) {
-		crc_update(&crc, 1);
-		crc_update(&crc, 0);
-	}
-	for (c = buf; c < buf + len; c += SSH_BLOCKSIZE) {
-		if (!CMP(S, c)) {
-			crc_update(&crc, 1);
-			crc_update(&crc, 0);
-		} else {
-			crc_update(&crc, 0);
-			crc_update(&crc, 0);
-		}
-	}
-	return (crc == 0);
-}
-
-
-/* Detect a crc32 compensation attack on a packet */
-int
-detect_attack(u_char *buf, u_int32_t len, u_char *IV)
-{
-	static u_int16_t *h = (u_int16_t *) NULL;
-	static u_int32_t n = HASH_MINSIZE / HASH_ENTRYSIZE;
-	u_int32_t i, j;
-	u_int32_t l, same;
-	u_char *c;
-	u_char *d;
-
-	if (len > (SSH_MAXBLOCKS * SSH_BLOCKSIZE) ||
-	    len % SSH_BLOCKSIZE != 0) {
-		fatal("detect_attack: bad length %d", len);
-	}
-	for (l = n; l < HASH_FACTOR(len / SSH_BLOCKSIZE); l = l << 2)
-		;
-
-	if (h == NULL) {
-		debug("Installing crc compensation attack detector.");
-		n = l;
-		h = (u_int16_t *) xmalloc(n * HASH_ENTRYSIZE);
-	} else {
-		if (l > n) {
-			n = l;
-			h = (u_int16_t *) xrealloc(h, n * HASH_ENTRYSIZE);
-		}
-	}
-
-	if (len <= HASH_MINBLOCKS) {
-		for (c = buf; c < buf + len; c += SSH_BLOCKSIZE) {
-			if (IV && (!CMP(c, IV))) {
-				if ((check_crc(c, buf, len, IV)))
-					return (DEATTACK_DETECTED);
-				else
-					break;
-			}
-			for (d = buf; d < c; d += SSH_BLOCKSIZE) {
-				if (!CMP(c, d)) {
-					if ((check_crc(c, buf, len, IV)))
-						return (DEATTACK_DETECTED);
-					else
-						break;
-				}
-			}
-		}
-		return (DEATTACK_OK);
-	}
-	memset(h, HASH_UNUSEDCHAR, n * HASH_ENTRYSIZE);
-
-	if (IV)
-		h[HASH(IV) & (n - 1)] = HASH_IV;
-
-	for (c = buf, same = j = 0; c < (buf + len); c += SSH_BLOCKSIZE, j++) {
-		for (i = HASH(c) & (n - 1); h[i] != HASH_UNUSED;
-		    i = (i + 1) & (n - 1)) {
-			if (h[i] == HASH_IV) {
-				if (!CMP(c, IV)) {
-					if (check_crc(c, buf, len, IV))
-						return (DEATTACK_DETECTED);
-					else
-						break;
-				}
-			} else if (!CMP(c, buf + h[i] * SSH_BLOCKSIZE)) {
-				if (++same > MAX_IDENTICAL)
-					return (DEATTACK_DOS_DETECTED);
-				if (check_crc(c, buf, len, IV))
-					return (DEATTACK_DETECTED);
-				else
-					break;
-			}
-		}
-		h[i] = j;
-	}
-	return (DEATTACK_OK);
-}
