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-rw-r--r--lib/libc/stdlib/rand.313
-rw-r--r--lib/libc/stdlib/random.317
2 files changed, 17 insertions, 13 deletions
diff --git a/lib/libc/stdlib/rand.3 b/lib/libc/stdlib/rand.3
index 3eb1a1d..6805073 100644
--- a/lib/libc/stdlib/rand.3
+++ b/lib/libc/stdlib/rand.3
@@ -55,9 +55,15 @@
.Fn rand_r "unsigned *ctx"
.Sh DESCRIPTION
.Bf -symbolic
+The functions described in this manual page are not cryptographically
+secure.
+Cryptographic applications should use
+.Xr arc4random 3
+instead.
+.Ef
+.Pp
These interfaces are obsoleted by
.Xr random 3 .
-.Ef
.Pp
The
.Fn rand
@@ -88,9 +94,6 @@ The
function initializes a seed using the
.Xr random 4
random number device which returns good random numbers.
-However, the
-.Fn rand
-function still remains unsuitable for cryptographic use.
.Pp
The
.Fn rand_r
@@ -105,8 +108,6 @@ For better generator quality, use
.Xr random 3
or
.Xr lrand48 3 .
-Applications requiring cryptographic quality randomness should use
-.Xr arc4random 3 .
.Sh SEE ALSO
.Xr arc4random 3 ,
.Xr lrand48 3 ,
diff --git a/lib/libc/stdlib/random.3 b/lib/libc/stdlib/random.3
index c6502bf..612a37e 100644
--- a/lib/libc/stdlib/random.3
+++ b/lib/libc/stdlib/random.3
@@ -53,6 +53,14 @@
.Ft char *
.Fn setstate "char *state"
.Sh DESCRIPTION
+.Bf -symbolic
+The functions described in this manual page are not cryptographically
+secure.
+Cryptographic applications should use
+.Xr arc4random 3
+instead.
+.Ef
+.Pp
The
.Fn random
function
@@ -98,10 +106,8 @@ as the seed.
.Pp
The
.Fn srandomdev
-routine initializes a state array using the
-.Xr random 4
-random number device which returns good random numbers,
-suitable for cryptographic use.
+routine initializes a state array using data from
+.Xr random 4 .
Note that this particular seeding
procedure can generate states which are impossible to reproduce by
calling
@@ -191,6 +197,3 @@ The historical implementation used to have a very weak seeding; the
random sequence did not vary much with the seed.
The current implementation employs a better pseudo-random number
generator for the initial state calculation.
-.Pp
-Applications requiring cryptographic quality randomness should use
-.Xr arc4random 3 .
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