random32: rename random32 to prandom

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@gmail.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Robert Love <robert.w.love@intel.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Cc: David Laight <david.laight@aculab.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 31 insertions, 30 deletions

diff --git a/lib/interval_tree_test_main.c b/lib/interval_tree_test_main.c
index b25903987f7a..245900b98c8e 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 938bde5876ac..d1830fade915 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 d7f491a54579..af38aedbd874 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();