[NET]: random functions can use nsec resolution instead of usec

In order to get more randomness for secure_tcpv6_sequence_number(),
secure_tcp_sequence_number(), secure_dccp_sequence_number() functions,
we can use the high resolution time services, providing nanosec
resolution.

I've also done two kmalloc()/kzalloc() conversions.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/char/random.c b/drivers/char/random.c
index 03af50f..46c1b97 100644 (file)
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -881,15 +881,15 @@ EXPORT_SYMBOL(get_random_bytes);
  */
 static void init_std_data(struct entropy_store *r)
 {
-       struct timeval tv;
+       ktime_t now;
        unsigned long flags;
 
        spin_lock_irqsave(&r->lock, flags);
        r->entropy_count = 0;
        spin_unlock_irqrestore(&r->lock, flags);
 
-       do_gettimeofday(&tv);
-       add_entropy_words(r, (__u32 *)&tv, sizeof(tv)/4);
+       now = ktime_get_real();
+       add_entropy_words(r, (__u32 *)&now, sizeof(now)/4);
        add_entropy_words(r, (__u32 *)utsname(),
                          sizeof(*(utsname()))/4);
 }
@@ -911,14 +911,12 @@ void rand_initialize_irq(int irq)
                return;
 
        /*
-        * If kmalloc returns null, we just won't use that entropy
+        * If kzalloc returns null, we just won't use that entropy
         * source.
         */
-       state = kmalloc(sizeof(struct timer_rand_state), GFP_KERNEL);
-       if (state) {
-               memset(state, 0, sizeof(struct timer_rand_state));
+       state = kzalloc(sizeof(struct timer_rand_state), GFP_KERNEL);
+       if (state)
                irq_timer_state[irq] = state;
-       }
 }
 
 #ifdef CONFIG_BLOCK
@@ -927,14 +925,12 @@ void rand_initialize_disk(struct gendisk *disk)
        struct timer_rand_state *state;
 
        /*
-        * If kmalloc returns null, we just won't use that entropy
+        * If kzalloc returns null, we just won't use that entropy
         * source.
         */
-       state = kmalloc(sizeof(struct timer_rand_state), GFP_KERNEL);
-       if (state) {
-               memset(state, 0, sizeof(struct timer_rand_state));
+       state = kzalloc(sizeof(struct timer_rand_state), GFP_KERNEL);
+       if (state)
                disk->random = state;
-       }
 }
 #endif
 
@@ -1469,7 +1465,6 @@ late_initcall(seqgen_init);
 __u32 secure_tcpv6_sequence_number(__be32 *saddr, __be32 *daddr,
                                   __be16 sport, __be16 dport)
 {
-       struct timeval tv;
        __u32 seq;
        __u32 hash[12];
        struct keydata *keyptr = get_keyptr();
@@ -1485,8 +1480,7 @@ __u32 secure_tcpv6_sequence_number(__be32 *saddr, __be32 *daddr,
        seq = twothirdsMD4Transform((const __u32 *)daddr, hash) & HASH_MASK;
        seq += keyptr->count;
 
-       do_gettimeofday(&tv);
-       seq += tv.tv_usec + tv.tv_sec * 1000000;
+       seq += ktime_get_real().tv64;
 
        return seq;
 }
@@ -1521,7 +1515,6 @@ __u32 secure_ip_id(__be32 daddr)
 __u32 secure_tcp_sequence_number(__be32 saddr, __be32 daddr,
                                 __be16 sport, __be16 dport)
 {
-       struct timeval tv;
        __u32 seq;
        __u32 hash[4];
        struct keydata *keyptr = get_keyptr();
@@ -1543,12 +1536,11 @@ __u32 secure_tcp_sequence_number(__be32 saddr, __be32 daddr,
         *      As close as possible to RFC 793, which
         *      suggests using a 250 kHz clock.
         *      Further reading shows this assumes 2 Mb/s networks.
-        *      For 10 Mb/s Ethernet, a 1 MHz clock is appropriate.
+        *      For 10 Gb/s Ethernet, a 1 GHz clock is appropriate.
         *      That's funny, Linux has one built in!  Use it!
         *      (Networks are faster now - should this be increased?)
         */
-       do_gettimeofday(&tv);
-       seq += tv.tv_usec + tv.tv_sec * 1000000;
+       seq += ktime_get_real().tv64;
 #if 0
        printk("init_seq(%lx, %lx, %d, %d) = %d\n",
               saddr, daddr, sport, dport, seq);
@@ -1596,7 +1588,6 @@ u32 secure_ipv6_port_ephemeral(const __be32 *saddr, const __be32 *daddr, __be16
 u64 secure_dccp_sequence_number(__be32 saddr, __be32 daddr,
                                __be16 sport, __be16 dport)
 {
-       struct timeval tv;
        u64 seq;
        __u32 hash[4];
        struct keydata *keyptr = get_keyptr();
@@ -1609,8 +1600,7 @@ u64 secure_dccp_sequence_number(__be32 saddr, __be32 daddr,
        seq = half_md4_transform(hash, keyptr->secret);
        seq |= ((u64)keyptr->count) << (32 - HASH_BITS);
 
-       do_gettimeofday(&tv);
-       seq += tv.tv_usec + tv.tv_sec * 1000000;
+       seq += ktime_get_real().tv64;
        seq &= (1ull << 48) - 1;
 #if 0
        printk("dccp init_seq(%lx, %lx, %d, %d) = %d\n",