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-rw-r--r--crypto/openssh/deattack.c156
1 files changed, 0 insertions, 156 deletions
diff --git a/crypto/openssh/deattack.c b/crypto/openssh/deattack.c
deleted file mode 100644
index 74a46c0e7b809..0000000000000
--- a/crypto/openssh/deattack.c
+++ /dev/null
@@ -1,156 +0,0 @@
-/* $OpenBSD: deattack.c,v 1.9 2000/09/07 20:27:51 deraadt Exp $ */
-
-/*
- * 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"
-#include "deattack.h"
-#include "ssh.h"
-#include "crc32.h"
-#include "getput.h"
-#include "xmalloc.h"
-
-/* 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))
-
-
-void
-crc_update(u_int32_t *a, u_int32_t b)
-{
- b ^= *a;
- *a = ssh_crc32((unsigned char *) &b, sizeof(b));
-}
-
-/* detect if a block is used in a particular pattern */
-int
-check_crc(unsigned char *S, unsigned char *buf, u_int32_t len,
- unsigned char *IV)
-{
- u_int32_t crc;
- unsigned 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(unsigned char *buf, u_int32_t len, unsigned char *IV)
-{
- static u_int16_t *h = (u_int16_t *) NULL;
- static u_int16_t n = HASH_MINSIZE / HASH_ENTRYSIZE;
- register u_int32_t i, j;
- u_int32_t l;
- register unsigned char *c;
- unsigned 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, 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 (check_crc(c, buf, len, IV))
- return (DEATTACK_DETECTED);
- else
- break;
- }
- }
- h[i] = j;
- }
- return (DEATTACK_OK);
-}