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commit 65c5d8ad7a46a83338c23dee66e208a014c3d3d2
Author: Ulrich Sibiller <uli42@gmx.de>
Date: Fri Mar 3 22:46:33 2017 +0100
Backport CVE-2017-2624 (timingsafe_memcmp)
Fixes ArcticaProject/nx-libs#365
These two commits:
commit 5c44169caed811e59a65ba346de1cadb46d266ec
Author: Adam Jackson <ajax@redhat.com>
Date: Thu Mar 2 17:20:30 2017 -0500
os: Squash missing declaration warning for timingsafe_memcmp
timingsafe_memcmp.c:21:1: warning: no previous prototype for ‘timingsafe_memcmp’ [-Wmissing-prototypes]
timingsafe_memcmp(const void *b1, const void *b2, size_t len)
Signed-off-by: Adam Jackson <ajax@redhat.com>
commit d7ac755f0b618eb1259d93c8a16ec6e39a18627c
Author: Matthieu Herrb <matthieu@herrb.eu>
Date: Tue Feb 28 19:18:25 2017 +0100
Use timingsafe_memcmp() to compare MIT-MAGIC-COOKIES CVE-2017-2624
Provide the function definition for systems that don't have it.
Signed-off-by: Matthieu Herrb <matthieu@herrb.eu>
Backported from Arctica GH 3.6.x branch.
v2: backport to nx-libs 3.6.x (Ulrich Sibiller)
v3: backport to nx-libs 3.5.0.x (Mihai Moldovan)
commit 22f542626cf9935fd55a899e21144111e481542c
Author: Ulrich Sibiller <uli42@gmx.de>
Date: Sat Mar 4 16:10:38 2017 +0100
os: add timingsafe_memcmp to Imake
There might be some library linking missing on platforms that deliver
timingsafe_memcmp but I cannot test that here.
Backported from Arctica GH 3.6.x branch.
v2: backport to nx-libs 3.5.0.x (Mihai Moldovan)
--- a/nx-X11/config/cf/Imake.tmpl
+++ b/nx-X11/config/cf/Imake.tmpl
@@ -484,6 +484,9 @@ XCOMM the platform-specific parameters -
#ifndef HasBasename
#define HasBasename YES
#endif
+#ifndef HasTimingsafeMemcmp
+#define HasTimingsafeMemcmp NO /* assume not */
+#endif
#ifndef HasGetopt
# if !defined(Win32Architecture) && !defined(OS2Architecture)
# define HasGetopt YES
--- a/nx-X11/programs/Xserver/include/os.h
+++ b/nx-X11/programs/Xserver/include/os.h
@@ -480,6 +480,11 @@ extern void AbortDDX(void);
extern void ddxGiveUp(void);
extern int TimeSinceLastInputEvent(void);
+#ifndef HAVE_TIMINGSAFE_MEMCMP
+extern _X_EXPORT int
+timingsafe_memcmp(const void *b1, const void *b2, size_t len);
+#endif
+
/* Logging. */
typedef enum _LogParameter {
XLOG_FLUSH,
--- a/nx-X11/programs/Xserver/os/Imakefile
+++ b/nx-X11/programs/Xserver/os/Imakefile
@@ -127,17 +127,22 @@ GETPEER_DEFINES = -DHAS_GETPEEREID
# endif
#endif
+#if !HasTimingsafeMemcmp
+TMEMCMP_SRCS = timingsafe_memcmp.c
+TMEMCMP_OBJS = timingsafe_memcmp.o
+#endif
+
BOOTSTRAPCFLAGS =
SRCS = WaitFor.c access.c connection.c io.c $(COLOR_SRCS) \
osinit.c utils.c log.c auth.c mitauth.c secauth.c \
$(XDMAUTHSRCS) $(RPCSRCS) $(KRB5SRCS) xdmcp.c OtherSources \
transport.c $(SNPRINTF_SRCS) $(STRLCAT_SRCS) \
- $(MALLOC_SRCS) $(LBX_SRCS) xprintf.c
+ $(MALLOC_SRCS) $(LBX_SRCS) xprintf.c $(TMEMCMP_SRCS)
OBJS = WaitFor.o access.o connection.o io.o $(COLOR_OBJS) \
osinit.o utils.o log.o auth.o mitauth.o secauth.o \
$(XDMAUTHOBJS) $(RPCOBJS) $(KRB5OBJS) xdmcp.o OtherObjects \
transport.o $(SNPRINTF_OBJS) $(STRLCAT_OBJS) \
- $(MALLOC_OBJS) $(LBX_OBJS) xprintf.o
+ $(MALLOC_OBJS) $(LBX_OBJS) xprintf.o $(TMEMCMP_OBJS)
#if SpecialMalloc
MEM_DEFINES = -DSPECIAL_MALLOC
--- a/nx-X11/programs/Xserver/os/mitauth.c
+++ b/nx-X11/programs/Xserver/os/mitauth.c
@@ -84,7 +84,7 @@ MitCheckCookie (
for (auth = mit_auth; auth; auth=auth->next) {
if (data_length == auth->len &&
- memcmp (data, auth->data, (int) data_length) == 0)
+ timingsafe_memcmp (data, auth->data, (int) data_length) == 0)
return auth->id;
}
*reason = "Invalid MIT-MAGIC-COOKIE-1 key";
--- /dev/null
+++ b/nx-X11/programs/Xserver/os/timingsafe_memcmp.c
@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2014 Google Inc.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <limits.h>
+#include <string.h>
+#include <X11/Xfuncproto.h>
+#include "os.h"
+
+int
+timingsafe_memcmp(const void *b1, const void *b2, size_t len)
+{
+ const unsigned char *p1 = b1, *p2 = b2;
+ size_t i;
+ int res = 0, done = 0;
+
+ for (i = 0; i < len; i++) {
+ /* lt is -1 if p1[i] < p2[i]; else 0. */
+ int lt = (p1[i] - p2[i]) >> CHAR_BIT;
+
+ /* gt is -1 if p1[i] > p2[i]; else 0. */
+ int gt = (p2[i] - p1[i]) >> CHAR_BIT;
+
+ /* cmp is 1 if p1[i] > p2[i]; -1 if p1[i] < p2[i]; else 0. */
+ int cmp = lt - gt;
+
+ /* set res = cmp if !done. */
+ res |= cmp & ~done;
+
+ /* set done if p1[i] != p2[i]. */
+ done |= lt | gt;
+ }
+
+ return (res);
+}