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-rw-r--r--lib/random32.c97
1 files changed, 73 insertions, 24 deletions
diff --git a/lib/random32.c b/lib/random32.c
index 938bde5876ac..52280d5526be 100644
--- a/lib/random32.c
+++ b/lib/random32.c
@@ -42,13 +42,13 @@
static DEFINE_PER_CPU(struct rnd_state, net_rand_state);
/**
- * prandom32 - seeded pseudo-random number generator.
+ * prandom_u32_state - seeded pseudo-random number generator.
* @state: pointer to state structure holding seeded state.
*
* This is used for pseudo-randomness with no outside seeding.
- * For more random results, use random32().
+ * For more random results, use prandom_u32().
*/
-u32 prandom32(struct rnd_state *state)
+u32 prandom_u32_state(struct rnd_state *state)
{
#define TAUSWORTHE(s,a,b,c,d) ((s&c)<<d) ^ (((s <<a) ^ s)>>b)
@@ -58,32 +58,81 @@ u32 prandom32(struct rnd_state *state)
return (state->s1 ^ state->s2 ^ state->s3);
}
-EXPORT_SYMBOL(prandom32);
+EXPORT_SYMBOL(prandom_u32_state);
/**
- * random32 - pseudo random number generator
+ * prandom_u32 - pseudo random number generator
*
* A 32 bit pseudo-random number is generated using a fast
* algorithm suitable for simulation. This algorithm is NOT
* considered safe for cryptographic use.
*/
-u32 random32(void)
+u32 prandom_u32(void)
{
unsigned long r;
struct rnd_state *state = &get_cpu_var(net_rand_state);
- r = prandom32(state);
+ r = prandom_u32_state(state);
put_cpu_var(state);
return r;
}
-EXPORT_SYMBOL(random32);
+EXPORT_SYMBOL(prandom_u32);
+
+/*
+ * prandom_bytes_state - get the requested number of pseudo-random bytes
+ *
+ * @state: pointer to state structure holding seeded state.
+ * @buf: where to copy the pseudo-random bytes to
+ * @bytes: the requested number of bytes
+ *
+ * This is used for pseudo-randomness with no outside seeding.
+ * For more random results, use prandom_bytes().
+ */
+void prandom_bytes_state(struct rnd_state *state, void *buf, int bytes)
+{
+ unsigned char *p = buf;
+ int i;
+
+ for (i = 0; i < round_down(bytes, sizeof(u32)); i += sizeof(u32)) {
+ u32 random = prandom_u32_state(state);
+ int j;
+
+ for (j = 0; j < sizeof(u32); j++) {
+ p[i + j] = random;
+ random >>= BITS_PER_BYTE;
+ }
+ }
+ if (i < bytes) {
+ u32 random = prandom_u32_state(state);
+
+ for (; i < bytes; i++) {
+ p[i] = random;
+ random >>= BITS_PER_BYTE;
+ }
+ }
+}
+EXPORT_SYMBOL(prandom_bytes_state);
+
+/**
+ * prandom_bytes - get the requested number of pseudo-random bytes
+ * @buf: where to copy the pseudo-random bytes to
+ * @bytes: the requested number of bytes
+ */
+void prandom_bytes(void *buf, int bytes)
+{
+ struct rnd_state *state = &get_cpu_var(net_rand_state);
+
+ prandom_bytes_state(state, buf, bytes);
+ put_cpu_var(state);
+}
+EXPORT_SYMBOL(prandom_bytes);
/**
- * srandom32 - add entropy to pseudo random number generator
+ * prandom_seed - add entropy to pseudo random number generator
* @seed: seed value
*
- * Add some additional seeding to the random32() pool.
+ * Add some additional seeding to the prandom pool.
*/
-void srandom32(u32 entropy)
+void prandom_seed(u32 entropy)
{
int i;
/*
@@ -95,13 +144,13 @@ void srandom32(u32 entropy)
state->s1 = __seed(state->s1 ^ entropy, 1);
}
}
-EXPORT_SYMBOL(srandom32);
+EXPORT_SYMBOL(prandom_seed);
/*
* Generate some initially weak seeding values to allow
- * to start the random32() engine.
+ * to start the prandom_u32() engine.
*/
-static int __init random32_init(void)
+static int __init prandom_init(void)
{
int i;
@@ -114,22 +163,22 @@ static int __init random32_init(void)
state->s3 = __seed(LCG(state->s2), 15);
/* "warm it up" */
- prandom32(state);
- prandom32(state);
- prandom32(state);
- prandom32(state);
- prandom32(state);
- prandom32(state);
+ prandom_u32_state(state);
+ prandom_u32_state(state);
+ prandom_u32_state(state);
+ prandom_u32_state(state);
+ prandom_u32_state(state);
+ prandom_u32_state(state);
}
return 0;
}
-core_initcall(random32_init);
+core_initcall(prandom_init);
/*
* Generate better values after random number generator
* is fully initialized.
*/
-static int __init random32_reseed(void)
+static int __init prandom_reseed(void)
{
int i;
@@ -143,8 +192,8 @@ static int __init random32_reseed(void)
state->s3 = __seed(seeds[2], 15);
/* mix it in */
- prandom32(state);
+ prandom_u32_state(state);
}
return 0;
}
-late_initcall(random32_reseed);
+late_initcall(prandom_reseed);