MFC: fix for predictable TCP sequence numbers, requires MFC of arc4ra…

…ndom.
freebsd · Oct 6, 2000 · d8e34cd · d8e34cd
1 parent bf483ab
commit d8e34cd
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Showing 5 changed files with 4 additions and 3 deletions.
diff --git a/sys/i386/conf/files.i386 b/sys/i386/conf/files.i386
@@ -256,6 +256,7 @@ libkern/strncmp.c		standard
 libkern/strncpy.c		standard
 libkern/udivdi3.c		standard
 libkern/umoddi3.c		standard
+libkern/arc4random.c		standard
 gnu/i386/fpemul/div_small.s	optional	gpl_math_emulate
 gnu/i386/fpemul/errors.c	optional	gpl_math_emulate
 gnu/i386/fpemul/fpu_arith.c	optional	gpl_math_emulate

diff --git a/sys/libkern/arc4random.c b/sys/libkern/arc4random.c
@@ -11,7 +11,6 @@
  */
 
 #include <sys/types.h>
-#include <sys/random.h>
 #include <sys/libkern.h>
 
 #define	ARC4_MAXRUNS 64

diff --git a/sys/netinet/tcp_seq.h b/sys/netinet/tcp_seq.h
@@ -91,7 +91,7 @@ extern tcp_cc	tcp_ccgen;		/* global connection count */
  * number in the range [0-0x3ffff] that is hard to predict.
  */
 #ifndef tcp_random18
-#define	tcp_random18()	((random() >> 14) & 0x3ffff)
+#define	tcp_random18()	(arc4random() & 0x3ffff)
 #endif
 #define	TCP_ISSINCR	(122*1024 + tcp_random18())
 

diff --git a/sys/netinet/tcp_subr.c b/sys/netinet/tcp_subr.c
@@ -104,7 +104,7 @@ void
 tcp_init()
 {
 
-	tcp_iss = random();	/* wrong, but better than a constant */
+	tcp_iss = arc4random();	/* wrong, but better than a constant */
 	tcp_ccgen = 1;
 	tcp_cleartaocache();
 	LIST_INIT(&tcb);

diff --git a/sys/sys/libkern.h b/sys/sys/libkern.h
@@ -61,6 +61,7 @@ static __inline u_long ulmax(u_long a, u_long b) { return (a > b ? a : b); }
 static __inline u_long ulmin(u_long a, u_long b) { return (a < b ? a : b); }
 
 /* Prototypes for non-quad routines. */
+u_int32_t	arc4random __P((void));
 int	 bcmp __P((const void *, const void *, size_t));
 #ifndef HAVE_INLINE_FFS
 int	 ffs __P((int));