diff options
-rw-r--r-- | include/linux/net.h | 7 | ||||
-rw-r--r-- | include/linux/random.h | 3 | ||||
-rw-r--r-- | lib/Makefile | 2 | ||||
-rw-r--r-- | lib/random32.c | 142 | ||||
-rw-r--r-- | net/core/dev.c | 2 | ||||
-rw-r--r-- | net/core/utils.c | 116 |
6 files changed, 150 insertions, 122 deletions
diff --git a/include/linux/net.h b/include/linux/net.h index c257f716e00f..15c733b816f0 100644 --- a/include/linux/net.h +++ b/include/linux/net.h @@ -19,6 +19,7 @@ #define _LINUX_NET_H #include <linux/wait.h> +#include <linux/random.h> #include <asm/socket.h> struct poll_table_struct; @@ -193,9 +194,9 @@ extern int sock_map_fd(struct socket *sock); extern struct socket *sockfd_lookup(int fd, int *err); #define sockfd_put(sock) fput(sock->file) extern int net_ratelimit(void); -extern unsigned long net_random(void); -extern void net_srandom(unsigned long); -extern void net_random_init(void); + +#define net_random() random32() +#define net_srandom(seed) srandom32(seed) extern int kernel_sendmsg(struct socket *sock, struct msghdr *msg, struct kvec *vec, size_t num, size_t len); diff --git a/include/linux/random.h b/include/linux/random.h index 5d6456bcdeba..0248b30e306d 100644 --- a/include/linux/random.h +++ b/include/linux/random.h @@ -69,6 +69,9 @@ extern 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); + #endif /* __KERNEL___ */ #endif /* _LINUX_RANDOM_H */ diff --git a/lib/Makefile b/lib/Makefile index 59070dbfbeb4..4b8052f6a7b0 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -12,7 +12,7 @@ lib-$(CONFIG_SMP) += cpumask.o lib-y += kobject.o kref.o kobject_uevent.o klist.o -obj-y += sort.o parser.o halfmd4.o iomap_copy.o debug_locks.o +obj-y += sort.o parser.o halfmd4.o iomap_copy.o debug_locks.o random32.o ifeq ($(CONFIG_DEBUG_KOBJECT),y) CFLAGS_kobject.o += -DDEBUG diff --git a/lib/random32.c b/lib/random32.c new file mode 100644 index 000000000000..4a15ce51cea7 --- /dev/null +++ b/lib/random32.c @@ -0,0 +1,142 @@ +/* + This is a maximally equidistributed combined Tausworthe generator + based on code from GNU Scientific Library 1.5 (30 Jun 2004) + + x_n = (s1_n ^ s2_n ^ s3_n) + + s1_{n+1} = (((s1_n & 4294967294) <<12) ^ (((s1_n <<13) ^ s1_n) >>19)) + s2_{n+1} = (((s2_n & 4294967288) << 4) ^ (((s2_n << 2) ^ s2_n) >>25)) + s3_{n+1} = (((s3_n & 4294967280) <<17) ^ (((s3_n << 3) ^ s3_n) >>11)) + + The period of this generator is about 2^88. + + From: P. L'Ecuyer, "Maximally Equidistributed Combined Tausworthe + Generators", Mathematics of Computation, 65, 213 (1996), 203--213. + + This is available on the net from L'Ecuyer's home page, + + http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps + ftp://ftp.iro.umontreal.ca/pub/simulation/lecuyer/papers/tausme.ps + + There is an erratum in the paper "Tables of Maximally + Equidistributed Combined LFSR Generators", Mathematics of + Computation, 68, 225 (1999), 261--269: + http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps + + ... the k_j most significant bits of z_j must be non- + zero, for each j. (Note: this restriction also applies to the + computer code given in [4], but was mistakenly not mentioned in + that paper.) + + This affects the seeding procedure by imposing the requirement + s1 > 1, s2 > 7, s3 > 15. + +*/ + +#include <linux/types.h> +#include <linux/percpu.h> +#include <linux/module.h> +#include <linux/random.h> + +struct rnd_state { + u32 s1, s2, s3; +}; + +static DEFINE_PER_CPU(struct rnd_state, net_rand_state); + +static u32 __random32(struct rnd_state *state) +{ +#define TAUSWORTHE(s,a,b,c,d) ((s&c)<<d) ^ (((s <<a) ^ s)>>b) + + state->s1 = TAUSWORTHE(state->s1, 13, 19, 4294967294UL, 12); + state->s2 = TAUSWORTHE(state->s2, 2, 25, 4294967288UL, 4); + state->s3 = TAUSWORTHE(state->s3, 3, 11, 4294967280UL, 17); + + return (state->s1 ^ state->s2 ^ state->s3); +} + +static void __set_random32(struct rnd_state *state, unsigned long s) +{ + if (s == 0) + s = 1; /* default seed is 1 */ + +#define LCG(n) (69069 * n) + state->s1 = LCG(s); + state->s2 = LCG(state->s1); + state->s3 = LCG(state->s2); + + /* "warm it up" */ + __random32(state); + __random32(state); + __random32(state); + __random32(state); + __random32(state); + __random32(state); +} + +/** + * random32 - 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) +{ + unsigned long r; + struct rnd_state *state = &get_cpu_var(net_rand_state); + r = __random32(state); + put_cpu_var(state); + return r; +} +EXPORT_SYMBOL(random32); + +/** + * srandom32 - add entropy to pseudo random number generator + * @seed: seed value + * + * Add some additional seeding to the random32() pool. + * Note: this pool is per cpu so it only affects current CPU. + */ +void srandom32(u32 entropy) +{ + struct rnd_state *state = &get_cpu_var(net_rand_state); + __set_random32(state, state->s1 ^ entropy); + put_cpu_var(state); +} +EXPORT_SYMBOL(srandom32); + +/* + * Generate some initially weak seeding values to allow + * to start the random32() engine. + */ +static int __init random32_init(void) +{ + int i; + + for_each_possible_cpu(i) { + struct rnd_state *state = &per_cpu(net_rand_state,i); + __set_random32(state, i + jiffies); + } + return 0; +} +core_initcall(random32_init); + +/* + * Generate better values after random number generator + * is fully initalized. + */ +static int __init random32_reseed(void) +{ + int i; + unsigned long seed; + + for_each_possible_cpu(i) { + struct rnd_state *state = &per_cpu(net_rand_state,i); + + get_random_bytes(&seed, sizeof(seed)); + __set_random32(state, seed); + } + return 0; +} +late_initcall(random32_reseed); diff --git a/net/core/dev.c b/net/core/dev.c index 4d891beab138..81c426adcd1e 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3502,8 +3502,6 @@ static int __init net_dev_init(void) BUG_ON(!dev_boot_phase); - net_random_init(); - if (dev_proc_init()) goto out; diff --git a/net/core/utils.c b/net/core/utils.c index 94c5d761c830..d93fe64f6693 100644 --- a/net/core/utils.c +++ b/net/core/utils.c @@ -30,119 +30,6 @@ #include <asm/system.h> #include <asm/uaccess.h> -/* - This is a maximally equidistributed combined Tausworthe generator - based on code from GNU Scientific Library 1.5 (30 Jun 2004) - - x_n = (s1_n ^ s2_n ^ s3_n) - - s1_{n+1} = (((s1_n & 4294967294) <<12) ^ (((s1_n <<13) ^ s1_n) >>19)) - s2_{n+1} = (((s2_n & 4294967288) << 4) ^ (((s2_n << 2) ^ s2_n) >>25)) - s3_{n+1} = (((s3_n & 4294967280) <<17) ^ (((s3_n << 3) ^ s3_n) >>11)) - - The period of this generator is about 2^88. - - From: P. L'Ecuyer, "Maximally Equidistributed Combined Tausworthe - Generators", Mathematics of Computation, 65, 213 (1996), 203--213. - - This is available on the net from L'Ecuyer's home page, - - http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps - ftp://ftp.iro.umontreal.ca/pub/simulation/lecuyer/papers/tausme.ps - - There is an erratum in the paper "Tables of Maximally - Equidistributed Combined LFSR Generators", Mathematics of - Computation, 68, 225 (1999), 261--269: - http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps - - ... the k_j most significant bits of z_j must be non- - zero, for each j. (Note: this restriction also applies to the - computer code given in [4], but was mistakenly not mentioned in - that paper.) - - This affects the seeding procedure by imposing the requirement - s1 > 1, s2 > 7, s3 > 15. - -*/ -struct nrnd_state { - u32 s1, s2, s3; -}; - -static DEFINE_PER_CPU(struct nrnd_state, net_rand_state); - -static u32 __net_random(struct nrnd_state *state) -{ -#define TAUSWORTHE(s,a,b,c,d) ((s&c)<<d) ^ (((s <<a) ^ s)>>b) - - state->s1 = TAUSWORTHE(state->s1, 13, 19, 4294967294UL, 12); - state->s2 = TAUSWORTHE(state->s2, 2, 25, 4294967288UL, 4); - state->s3 = TAUSWORTHE(state->s3, 3, 11, 4294967280UL, 17); - - return (state->s1 ^ state->s2 ^ state->s3); -} - -static void __net_srandom(struct nrnd_state *state, unsigned long s) -{ - if (s == 0) - s = 1; /* default seed is 1 */ - -#define LCG(n) (69069 * n) - state->s1 = LCG(s); - state->s2 = LCG(state->s1); - state->s3 = LCG(state->s2); - - /* "warm it up" */ - __net_random(state); - __net_random(state); - __net_random(state); - __net_random(state); - __net_random(state); - __net_random(state); -} - - -unsigned long net_random(void) -{ - unsigned long r; - struct nrnd_state *state = &get_cpu_var(net_rand_state); - r = __net_random(state); - put_cpu_var(state); - return r; -} - - -void net_srandom(unsigned long entropy) -{ - struct nrnd_state *state = &get_cpu_var(net_rand_state); - __net_srandom(state, state->s1^entropy); - put_cpu_var(state); -} - -void __init net_random_init(void) -{ - int i; - - for_each_possible_cpu(i) { - struct nrnd_state *state = &per_cpu(net_rand_state,i); - __net_srandom(state, i+jiffies); - } -} - -static int net_random_reseed(void) -{ - int i; - unsigned long seed; - - for_each_possible_cpu(i) { - struct nrnd_state *state = &per_cpu(net_rand_state,i); - - get_random_bytes(&seed, sizeof(seed)); - __net_srandom(state, seed); - } - return 0; -} -late_initcall(net_random_reseed); - int net_msg_cost = 5*HZ; int net_msg_burst = 10; @@ -153,10 +40,7 @@ int net_ratelimit(void) { return __printk_ratelimit(net_msg_cost, net_msg_burst); } - -EXPORT_SYMBOL(net_random); EXPORT_SYMBOL(net_ratelimit); -EXPORT_SYMBOL(net_srandom); /* * Convert an ASCII string to binary IP. |