[PATCH v3 01/11] random32: rename random32 to prandom

From: Akinobu Mita
Date: Tue Nov 13 2012 - 08:37:25 EST


This renames all random32 functions to have 'prandom_' prefix as follows:

void prandom_seed(u32 seed); /* rename from srandom32() */
u32 prandom_u32(void); /* rename from random32() */
void prandom_seed_state(struct rnd_state *state, u64 seed);
/* rename from prandom32_seed() */
u32 prandom_u32_state(struct rnd_state *state);
/* rename from prandom32() */

The purpose of this renaming is to prevent some kernel developers from
assuming that prandom32() and random32() might imply that only
prandom32() was the one using a pseudo-random number generator by
prandom32's "p", and the result may be a very embarassing security
exposure. This concern was expressed by Theodore Ts'o.

And furthermore, I'm going to introduce new functions for getting the
requested number of pseudo-random bytes. If I continue to use both
prandom32 and random32 prefixes for these functions, the confusion
is getting worse.

As a result of this renaming, "prandom_" is the common prefix for
pseudo-random number library.

Currently, srandom32() and random32() are preserved because it is
difficult to rename too many users at once.

Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx>
Cc: "Theodore Ts'o" <tytso@xxxxxxx>
Cc: Robert Love <robert.w.love@xxxxxxxxx>
Cc: devel@xxxxxxxxxxxxx
Cc: Michel Lespinasse <walken@xxxxxxxxxx>
Cc: Valdis Kletnieks <valdis.kletnieks@xxxxxx>
Cc: David Laight <david.laight@xxxxxxxxxx>
---
* v3
- change common prefix from 'random32_' to 'prandom_'

drivers/scsi/fcoe/fcoe_ctlr.c | 4 ++--
include/linux/random.h | 17 ++++++++++-----
lib/interval_tree_test_main.c | 7 ++++---
lib/random32.c | 48 +++++++++++++++++++++----------------------
lib/rbtree_test.c | 6 +++---
5 files changed, 45 insertions(+), 37 deletions(-)

diff --git a/drivers/scsi/fcoe/fcoe_ctlr.c b/drivers/scsi/fcoe/fcoe_ctlr.c
index 2ebe03a..4a909d7 100644
--- a/drivers/scsi/fcoe/fcoe_ctlr.c
+++ b/drivers/scsi/fcoe/fcoe_ctlr.c
@@ -2144,7 +2144,7 @@ static void fcoe_ctlr_vn_restart(struct fcoe_ctlr *fip)
*/
port_id = fip->port_id;
if (fip->probe_tries)
- port_id = prandom32(&fip->rnd_state) & 0xffff;
+ port_id = prandom_u32_state(&fip->rnd_state) & 0xffff;
else if (!port_id)
port_id = fip->lp->wwpn & 0xffff;
if (!port_id || port_id == 0xffff)
@@ -2169,7 +2169,7 @@ static void fcoe_ctlr_vn_restart(struct fcoe_ctlr *fip)
static void fcoe_ctlr_vn_start(struct fcoe_ctlr *fip)
{
fip->probe_tries = 0;
- prandom32_seed(&fip->rnd_state, fip->lp->wwpn);
+ prandom_seed_state(&fip->rnd_state, fip->lp->wwpn);
fcoe_ctlr_vn_restart(fip);
}

diff --git a/include/linux/random.h b/include/linux/random.h
index 6330ed4..db6debc 100644
--- a/include/linux/random.h
+++ b/include/linux/random.h
@@ -25,10 +25,17 @@ extern const struct file_operations random_fops, urandom_fops;
unsigned int get_random_int(void);
unsigned long randomize_range(unsigned long start, unsigned long end, unsigned long len);

-u32 random32(void);
-void srandom32(u32 seed);
+u32 prandom_u32(void);
+void prandom_seed(u32 seed);

-u32 prandom32(struct rnd_state *);
+/*
+ * These macros are preserved for backward compatibility and should be
+ * removed as soon as a transition is finished.
+ */
+#define random32() prandom_u32()
+#define srandom32(seed) prandom_seed(seed)
+
+u32 prandom_u32_state(struct rnd_state *);

/*
* Handle minimum values for seeds
@@ -39,11 +46,11 @@ static inline u32 __seed(u32 x, u32 m)
}

/**
- * prandom32_seed - set seed for prandom32().
+ * prandom_seed_state - set seed for prandom_u32_state().
* @state: pointer to state structure to receive the seed.
* @seed: arbitrary 64-bit value to use as a seed.
*/
-static inline void prandom32_seed(struct rnd_state *state, u64 seed)
+static inline void prandom_seed_state(struct rnd_state *state, u64 seed)
{
u32 i = (seed >> 32) ^ (seed << 10) ^ seed;

diff --git a/lib/interval_tree_test_main.c b/lib/interval_tree_test_main.c
index b259039..245900b 100644
--- a/lib/interval_tree_test_main.c
+++ b/lib/interval_tree_test_main.c
@@ -30,7 +30,8 @@ static void init(void)
{
int i;
for (i = 0; i < NODES; i++) {
- u32 a = prandom32(&rnd), b = prandom32(&rnd);
+ u32 a = prandom_u32_state(&rnd);
+ u32 b = prandom_u32_state(&rnd);
if (a <= b) {
nodes[i].start = a;
nodes[i].last = b;
@@ -40,7 +41,7 @@ static void init(void)
}
}
for (i = 0; i < SEARCHES; i++)
- queries[i] = prandom32(&rnd);
+ queries[i] = prandom_u32_state(&rnd);
}

static int interval_tree_test_init(void)
@@ -51,7 +52,7 @@ static int interval_tree_test_init(void)

printk(KERN_ALERT "interval tree insert/remove");

- prandom32_seed(&rnd, 3141592653589793238ULL);
+ prandom_seed_state(&rnd, 3141592653589793238ULL);
init();

time1 = get_cycles();
diff --git a/lib/random32.c b/lib/random32.c
index 938bde5..d1830fa 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 +58,32 @@ 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);

/**
- * 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 +95,13 @@ 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 +114,22 @@ 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 +143,8 @@ 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);
diff --git a/lib/rbtree_test.c b/lib/rbtree_test.c
index 268b239..da96578 100644
--- a/lib/rbtree_test.c
+++ b/lib/rbtree_test.c
@@ -96,8 +96,8 @@ static void init(void)
{
int i;
for (i = 0; i < NODES; i++) {
- nodes[i].key = prandom32(&rnd);
- nodes[i].val = prandom32(&rnd);
+ nodes[i].key = prandom_u32_state(&rnd);
+ nodes[i].val = prandom_u32_state(&rnd);
}
}

@@ -155,7 +155,7 @@ static int rbtree_test_init(void)

printk(KERN_ALERT "rbtree testing");

- prandom32_seed(&rnd, 3141592653589793238ULL);
+ prandom_seed_state(&rnd, 3141592653589793238ULL);
init();

time1 = get_cycles();
--
1.7.11.7

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