#include <linux/spinlock.h>
#include <linux/percpu.h>
#include <linux/cryptohash.h>
+#include <linux/fips.h>
#ifdef CONFIG_GENERIC_HARDIRQS
# include <linux/irq.h>
#define INPUT_POOL_WORDS 128
#define OUTPUT_POOL_WORDS 32
#define SEC_XFER_SIZE 512
+#define EXTRACT_SIZE 10
/*
* The minimum number of bits of entropy before we wake up a read on
struct poolinfo *poolinfo;
__u32 *pool;
const char *name;
- int limit;
struct entropy_store *pull;
+ int limit;
/* read-write data: */
spinlock_t lock;
unsigned add_ptr;
int entropy_count;
int input_rotate;
+ __u8 last_data[EXTRACT_SIZE];
};
static __u32 input_pool_data[INPUT_POOL_WORDS];
preempt_disable();
/* if over the trickle threshold, use only 1 in 4096 samples */
if (input_pool.entropy_count > trickle_thresh &&
- (__get_cpu_var(trickle_count)++ & 0xfff))
+ ((__this_cpu_inc_return(trickle_count) - 1) & 0xfff))
goto out;
sample.jiffies = jiffies;
}
#endif
-#define EXTRACT_SIZE 10
-
/*********************************************************************
*
* Entropy extraction routines
{
ssize_t ret = 0, i;
__u8 tmp[EXTRACT_SIZE];
+ unsigned long flags;
xfer_secondary_pool(r, nbytes);
nbytes = account(r, nbytes, min, reserved);
while (nbytes) {
extract_buf(r, tmp);
+
+ if (fips_enabled) {
+ spin_lock_irqsave(&r->lock, flags);
+ if (!memcmp(tmp, r->last_data, EXTRACT_SIZE))
+ panic("Hardware RNG duplicated output!\n");
+ memcpy(r->last_data, tmp, EXTRACT_SIZE);
+ spin_unlock_irqrestore(&r->lock, flags);
+ }
i = min_t(int, nbytes, EXTRACT_SIZE);
memcpy(buf, tmp, i);
nbytes -= i;
/* like a named pipe */
}
- /*
- * If we gave the user some bytes, update the access time.
- */
- if (count)
- file_accessed(file);
-
return (count ? count : retval);
}
size_t count, loff_t *ppos)
{
size_t ret;
- struct inode *inode = file->f_path.dentry->d_inode;
ret = write_pool(&blocking_pool, buffer, count);
if (ret)
if (ret)
return ret;
- inode->i_mtime = current_fs_time(inode->i_sb);
- mark_inode_dirty(inode);
return (ssize_t)count;
}
.poll = random_poll,
.unlocked_ioctl = random_ioctl,
.fasync = random_fasync,
+ .llseek = noop_llseek,
};
const struct file_operations urandom_fops = {
.write = random_write,
.unlocked_ioctl = random_ioctl,
.fasync = random_fasync,
+ .llseek = noop_llseek,
};
/***************************************************************
void generate_random_uuid(unsigned char uuid_out[16])
{
get_random_bytes(uuid_out, 16);
- /* Set UUID version to 4 --- truely random generation */
+ /* Set UUID version to 4 --- truly random generation */
uuid_out[6] = (uuid_out[6] & 0x0F) | 0x40;
/* Set the UUID variant to DCE */
uuid_out[8] = (uuid_out[8] & 0x3F) | 0x80;
* as an ASCII string in the standard UUID format. If accesses via the
* sysctl system call, it is returned as 16 bytes of binary data.
*/
-static int proc_do_uuid(ctl_table *table, int write, struct file *filp,
+static int proc_do_uuid(ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
ctl_table fake_table;
if (uuid[8] == 0)
generate_random_uuid(uuid);
- sprintf(buf, "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-"
- "%02x%02x%02x%02x%02x%02x",
- uuid[0], uuid[1], uuid[2], uuid[3],
- uuid[4], uuid[5], uuid[6], uuid[7],
- uuid[8], uuid[9], uuid[10], uuid[11],
- uuid[12], uuid[13], uuid[14], uuid[15]);
+ sprintf(buf, "%pU", uuid);
+
fake_table.data = buf;
fake_table.maxlen = sizeof(buf);
- return proc_dostring(&fake_table, write, filp, buffer, lenp, ppos);
-}
-
-static int uuid_strategy(ctl_table *table,
- void __user *oldval, size_t __user *oldlenp,
- void __user *newval, size_t newlen)
-{
- unsigned char tmp_uuid[16], *uuid;
- unsigned int len;
-
- if (!oldval || !oldlenp)
- return 1;
-
- uuid = table->data;
- if (!uuid) {
- uuid = tmp_uuid;
- uuid[8] = 0;
- }
- if (uuid[8] == 0)
- generate_random_uuid(uuid);
-
- if (get_user(len, oldlenp))
- return -EFAULT;
- if (len) {
- if (len > 16)
- len = 16;
- if (copy_to_user(oldval, uuid, len) ||
- put_user(len, oldlenp))
- return -EFAULT;
- }
- return 1;
+ return proc_dostring(&fake_table, write, buffer, lenp, ppos);
}
static int sysctl_poolsize = INPUT_POOL_WORDS * 32;
ctl_table random_table[] = {
{
- .ctl_name = RANDOM_POOLSIZE,
.procname = "poolsize",
.data = &sysctl_poolsize,
.maxlen = sizeof(int),
.mode = 0444,
- .proc_handler = &proc_dointvec,
+ .proc_handler = proc_dointvec,
},
{
- .ctl_name = RANDOM_ENTROPY_COUNT,
.procname = "entropy_avail",
.maxlen = sizeof(int),
.mode = 0444,
- .proc_handler = &proc_dointvec,
+ .proc_handler = proc_dointvec,
.data = &input_pool.entropy_count,
},
{
- .ctl_name = RANDOM_READ_THRESH,
.procname = "read_wakeup_threshold",
.data = &random_read_wakeup_thresh,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = &proc_dointvec_minmax,
- .strategy = &sysctl_intvec,
+ .proc_handler = proc_dointvec_minmax,
.extra1 = &min_read_thresh,
.extra2 = &max_read_thresh,
},
{
- .ctl_name = RANDOM_WRITE_THRESH,
.procname = "write_wakeup_threshold",
.data = &random_write_wakeup_thresh,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = &proc_dointvec_minmax,
- .strategy = &sysctl_intvec,
+ .proc_handler = proc_dointvec_minmax,
.extra1 = &min_write_thresh,
.extra2 = &max_write_thresh,
},
{
- .ctl_name = RANDOM_BOOT_ID,
.procname = "boot_id",
.data = &sysctl_bootid,
.maxlen = 16,
.mode = 0444,
- .proc_handler = &proc_do_uuid,
- .strategy = &uuid_strategy,
+ .proc_handler = proc_do_uuid,
},
{
- .ctl_name = RANDOM_UUID,
.procname = "uuid",
.maxlen = 16,
.mode = 0444,
- .proc_handler = &proc_do_uuid,
- .strategy = &uuid_strategy,
+ .proc_handler = proc_do_uuid,
},
- { .ctl_name = 0 }
+ { }
};
#endif /* CONFIG_SYSCTL */
-/********************************************************************
- *
- * Random funtions for networking
- *
- ********************************************************************/
-
-/*
- * TCP initial sequence number picking. This uses the random number
- * generator to pick an initial secret value. This value is hashed
- * along with the TCP endpoint information to provide a unique
- * starting point for each pair of TCP endpoints. This defeats
- * attacks which rely on guessing the initial TCP sequence number.
- * This algorithm was suggested by Steve Bellovin.
- *
- * Using a very strong hash was taking an appreciable amount of the total
- * TCP connection establishment time, so this is a weaker hash,
- * compensated for by changing the secret periodically.
- */
-
-/* F, G and H are basic MD4 functions: selection, majority, parity */
-#define F(x, y, z) ((z) ^ ((x) & ((y) ^ (z))))
-#define G(x, y, z) (((x) & (y)) + (((x) ^ (y)) & (z)))
-#define H(x, y, z) ((x) ^ (y) ^ (z))
-
-/*
- * The generic round function. The application is so specific that
- * we don't bother protecting all the arguments with parens, as is generally
- * good macro practice, in favor of extra legibility.
- * Rotation is separate from addition to prevent recomputation
- */
-#define ROUND(f, a, b, c, d, x, s) \
- (a += f(b, c, d) + x, a = (a << s) | (a >> (32 - s)))
-#define K1 0
-#define K2 013240474631UL
-#define K3 015666365641UL
-
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
-
-static __u32 twothirdsMD4Transform(__u32 const buf[4], __u32 const in[12])
-{
- __u32 a = buf[0], b = buf[1], c = buf[2], d = buf[3];
-
- /* Round 1 */
- ROUND(F, a, b, c, d, in[ 0] + K1, 3);
- ROUND(F, d, a, b, c, in[ 1] + K1, 7);
- ROUND(F, c, d, a, b, in[ 2] + K1, 11);
- ROUND(F, b, c, d, a, in[ 3] + K1, 19);
- ROUND(F, a, b, c, d, in[ 4] + K1, 3);
- ROUND(F, d, a, b, c, in[ 5] + K1, 7);
- ROUND(F, c, d, a, b, in[ 6] + K1, 11);
- ROUND(F, b, c, d, a, in[ 7] + K1, 19);
- ROUND(F, a, b, c, d, in[ 8] + K1, 3);
- ROUND(F, d, a, b, c, in[ 9] + K1, 7);
- ROUND(F, c, d, a, b, in[10] + K1, 11);
- ROUND(F, b, c, d, a, in[11] + K1, 19);
-
- /* Round 2 */
- ROUND(G, a, b, c, d, in[ 1] + K2, 3);
- ROUND(G, d, a, b, c, in[ 3] + K2, 5);
- ROUND(G, c, d, a, b, in[ 5] + K2, 9);
- ROUND(G, b, c, d, a, in[ 7] + K2, 13);
- ROUND(G, a, b, c, d, in[ 9] + K2, 3);
- ROUND(G, d, a, b, c, in[11] + K2, 5);
- ROUND(G, c, d, a, b, in[ 0] + K2, 9);
- ROUND(G, b, c, d, a, in[ 2] + K2, 13);
- ROUND(G, a, b, c, d, in[ 4] + K2, 3);
- ROUND(G, d, a, b, c, in[ 6] + K2, 5);
- ROUND(G, c, d, a, b, in[ 8] + K2, 9);
- ROUND(G, b, c, d, a, in[10] + K2, 13);
-
- /* Round 3 */
- ROUND(H, a, b, c, d, in[ 3] + K3, 3);
- ROUND(H, d, a, b, c, in[ 7] + K3, 9);
- ROUND(H, c, d, a, b, in[11] + K3, 11);
- ROUND(H, b, c, d, a, in[ 2] + K3, 15);
- ROUND(H, a, b, c, d, in[ 6] + K3, 3);
- ROUND(H, d, a, b, c, in[10] + K3, 9);
- ROUND(H, c, d, a, b, in[ 1] + K3, 11);
- ROUND(H, b, c, d, a, in[ 5] + K3, 15);
- ROUND(H, a, b, c, d, in[ 9] + K3, 3);
- ROUND(H, d, a, b, c, in[ 0] + K3, 9);
- ROUND(H, c, d, a, b, in[ 4] + K3, 11);
- ROUND(H, b, c, d, a, in[ 8] + K3, 15);
-
- return buf[1] + b; /* "most hashed" word */
- /* Alternative: return sum of all words? */
-}
-#endif
-
-#undef ROUND
-#undef F
-#undef G
-#undef H
-#undef K1
-#undef K2
-#undef K3
-
-/* This should not be decreased so low that ISNs wrap too fast. */
-#define REKEY_INTERVAL (300 * HZ)
-/*
- * Bit layout of the tcp sequence numbers (before adding current time):
- * bit 24-31: increased after every key exchange
- * bit 0-23: hash(source,dest)
- *
- * The implementation is similar to the algorithm described
- * in the Appendix of RFC 1185, except that
- * - it uses a 1 MHz clock instead of a 250 kHz clock
- * - it performs a rekey every 5 minutes, which is equivalent
- * to a (source,dest) tulple dependent forward jump of the
- * clock by 0..2^(HASH_BITS+1)
- *
- * Thus the average ISN wraparound time is 68 minutes instead of
- * 4.55 hours.
- *
- * SMP cleanup and lock avoidance with poor man's RCU.
- * Manfred Spraul <manfred@colorfullife.com>
- *
- */
-#define COUNT_BITS 8
-#define COUNT_MASK ((1 << COUNT_BITS) - 1)
-#define HASH_BITS 24
-#define HASH_MASK ((1 << HASH_BITS) - 1)
-
-static struct keydata {
- __u32 count; /* already shifted to the final position */
- __u32 secret[12];
-} ____cacheline_aligned ip_keydata[2];
-
-static unsigned int ip_cnt;
-
-static void rekey_seq_generator(struct work_struct *work);
-
-static DECLARE_DELAYED_WORK(rekey_work, rekey_seq_generator);
-
-/*
- * Lock avoidance:
- * The ISN generation runs lockless - it's just a hash over random data.
- * State changes happen every 5 minutes when the random key is replaced.
- * Synchronization is performed by having two copies of the hash function
- * state and rekey_seq_generator always updates the inactive copy.
- * The copy is then activated by updating ip_cnt.
- * The implementation breaks down if someone blocks the thread
- * that processes SYN requests for more than 5 minutes. Should never
- * happen, and even if that happens only a not perfectly compliant
- * ISN is generated, nothing fatal.
- */
-static void rekey_seq_generator(struct work_struct *work)
-{
- struct keydata *keyptr = &ip_keydata[1 ^ (ip_cnt & 1)];
-
- get_random_bytes(keyptr->secret, sizeof(keyptr->secret));
- keyptr->count = (ip_cnt & COUNT_MASK) << HASH_BITS;
- smp_wmb();
- ip_cnt++;
- schedule_delayed_work(&rekey_work, REKEY_INTERVAL);
-}
-
-static inline struct keydata *get_keyptr(void)
-{
- struct keydata *keyptr = &ip_keydata[ip_cnt & 1];
-
- smp_rmb();
-
- return keyptr;
-}
+static u32 random_int_secret[MD5_MESSAGE_BYTES / 4] ____cacheline_aligned;
-static __init int seqgen_init(void)
+static int __init random_int_secret_init(void)
{
- rekey_seq_generator(NULL);
+ get_random_bytes(random_int_secret, sizeof(random_int_secret));
return 0;
}
-late_initcall(seqgen_init);
-
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
-__u32 secure_tcpv6_sequence_number(__be32 *saddr, __be32 *daddr,
- __be16 sport, __be16 dport)
-{
- __u32 seq;
- __u32 hash[12];
- struct keydata *keyptr = get_keyptr();
-
- /* The procedure is the same as for IPv4, but addresses are longer.
- * Thus we must use twothirdsMD4Transform.
- */
-
- memcpy(hash, saddr, 16);
- hash[4] = ((__force u16)sport << 16) + (__force u16)dport;
- memcpy(&hash[5], keyptr->secret, sizeof(__u32) * 7);
-
- seq = twothirdsMD4Transform((const __u32 *)daddr, hash) & HASH_MASK;
- seq += keyptr->count;
-
- seq += ktime_to_ns(ktime_get_real());
-
- return seq;
-}
-EXPORT_SYMBOL(secure_tcpv6_sequence_number);
-#endif
-
-/* The code below is shamelessly stolen from secure_tcp_sequence_number().
- * All blames to Andrey V. Savochkin <saw@msu.ru>.
- */
-__u32 secure_ip_id(__be32 daddr)
-{
- struct keydata *keyptr;
- __u32 hash[4];
-
- keyptr = get_keyptr();
-
- /*
- * Pick a unique starting offset for each IP destination.
- * The dest ip address is placed in the starting vector,
- * which is then hashed with random data.
- */
- hash[0] = (__force __u32)daddr;
- hash[1] = keyptr->secret[9];
- hash[2] = keyptr->secret[10];
- hash[3] = keyptr->secret[11];
-
- return half_md4_transform(hash, keyptr->secret);
-}
-
-#ifdef CONFIG_INET
-
-__u32 secure_tcp_sequence_number(__be32 saddr, __be32 daddr,
- __be16 sport, __be16 dport)
-{
- __u32 seq;
- __u32 hash[4];
- struct keydata *keyptr = get_keyptr();
-
- /*
- * Pick a unique starting offset for each TCP connection endpoints
- * (saddr, daddr, sport, dport).
- * Note that the words are placed into the starting vector, which is
- * then mixed with a partial MD4 over random data.
- */
- hash[0] = (__force u32)saddr;
- hash[1] = (__force u32)daddr;
- hash[2] = ((__force u16)sport << 16) + (__force u16)dport;
- hash[3] = keyptr->secret[11];
-
- seq = half_md4_transform(hash, keyptr->secret) & HASH_MASK;
- seq += keyptr->count;
- /*
- * 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 should be ok, but
- * we also need to limit the resolution so that the u32 seq
- * overlaps less than one time per MSL (2 minutes).
- * Choosing a clock of 64 ns period is OK. (period of 274 s)
- */
- seq += ktime_to_ns(ktime_get_real()) >> 6;
-
- return seq;
-}
-
-/* Generate secure starting point for ephemeral IPV4 transport port search */
-u32 secure_ipv4_port_ephemeral(__be32 saddr, __be32 daddr, __be16 dport)
-{
- struct keydata *keyptr = get_keyptr();
- u32 hash[4];
-
- /*
- * Pick a unique starting offset for each ephemeral port search
- * (saddr, daddr, dport) and 48bits of random data.
- */
- hash[0] = (__force u32)saddr;
- hash[1] = (__force u32)daddr;
- hash[2] = (__force u32)dport ^ keyptr->secret[10];
- hash[3] = keyptr->secret[11];
-
- return half_md4_transform(hash, keyptr->secret);
-}
-EXPORT_SYMBOL_GPL(secure_ipv4_port_ephemeral);
-
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
-u32 secure_ipv6_port_ephemeral(const __be32 *saddr, const __be32 *daddr,
- __be16 dport)
-{
- struct keydata *keyptr = get_keyptr();
- u32 hash[12];
-
- memcpy(hash, saddr, 16);
- hash[4] = (__force u32)dport;
- memcpy(&hash[5], keyptr->secret, sizeof(__u32) * 7);
-
- return twothirdsMD4Transform((const __u32 *)daddr, hash);
-}
-#endif
-
-#if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
-/* Similar to secure_tcp_sequence_number but generate a 48 bit value
- * bit's 32-47 increase every key exchange
- * 0-31 hash(source, dest)
- */
-u64 secure_dccp_sequence_number(__be32 saddr, __be32 daddr,
- __be16 sport, __be16 dport)
-{
- u64 seq;
- __u32 hash[4];
- struct keydata *keyptr = get_keyptr();
-
- hash[0] = (__force u32)saddr;
- hash[1] = (__force u32)daddr;
- hash[2] = ((__force u16)sport << 16) + (__force u16)dport;
- hash[3] = keyptr->secret[11];
-
- seq = half_md4_transform(hash, keyptr->secret);
- seq |= ((u64)keyptr->count) << (32 - HASH_BITS);
-
- seq += ktime_to_ns(ktime_get_real());
- seq &= (1ull << 48) - 1;
-
- return seq;
-}
-EXPORT_SYMBOL(secure_dccp_sequence_number);
-#endif
-
-#endif /* CONFIG_INET */
-
+late_initcall(random_int_secret_init);
/*
* Get a random word for internal kernel use only. Similar to urandom but
* value is not cryptographically secure but for several uses the cost of
* depleting entropy is too high
*/
+DEFINE_PER_CPU(__u32 [MD5_DIGEST_WORDS], get_random_int_hash);
unsigned int get_random_int(void)
{
- /*
- * Use IP's RNG. It suits our purpose perfectly: it re-keys itself
- * every second, from the entropy pool (and thus creates a limited
- * drain on it), and uses halfMD4Transform within the second. We
- * also mix it with jiffies and the PID:
- */
- return secure_ip_id((__force __be32)(current->pid + jiffies));
+ __u32 *hash = get_cpu_var(get_random_int_hash);
+ unsigned int ret;
+
+ hash[0] += current->pid + jiffies + get_cycles();
+ md5_transform(hash, random_int_secret);
+ ret = hash[0];
+ put_cpu_var(get_random_int_hash);
+
+ return ret;
}
/*
projects / linux-flexiantxendom0-natty.git / blobdiff