---------------------------
-What: IRQF_SAMPLE_RANDOM
-Check: IRQF_SAMPLE_RANDOM
-When: July 2009
-
-Why: Many of IRQF_SAMPLE_RANDOM users are technically bogus as entropy
- sources in the kernel's current entropy model. To resolve this, every
- input point to the kernel's entropy pool needs to better document the
- type of entropy source it actually is. This will be replaced with
- additional add_*_randomness functions in drivers/char/random.c
-
-Who: Robin Getz <rgetz@blackfin.uclinux.org> & Matt Mackall <mpm@selenic.com>
-
----------------------------
-
What: The ieee80211_regdom module parameter
When: March 2010 / desktop catchup
F: drivers/block/brd.c
RANDOM NUMBER DRIVER
-M: Matt Mackall <mpm@selenic.com>
+M: Theodore Ts'o" <tytso@mit.edu>
S: Maintained
F: drivers/char/random.c
}
gpio_direction_input(PALMZ71_USBDETECT_GPIO);
if (request_irq(gpio_to_irq(PALMZ71_USBDETECT_GPIO),
- palmz71_powercable, IRQF_SAMPLE_RANDOM,
- "palmz71-cable", NULL))
+ palmz71_powercable, 0, "palmz71-cable", NULL))
printk(KERN_ERR
"IRQ request for power cable failed!\n");
palmz71_powercable(gpio_to_irq(PALMZ71_USBDETECT_GPIO), NULL);
init_timer(&mmc_timer);
mmc_timer.data = (unsigned long) data;
return request_irq(LUBBOCK_SD_IRQ, lubbock_detect_int,
- IRQF_SAMPLE_RANDOM, "lubbock-sd-detect", data);
+ 0, "lubbock-sd-detect", data);
}
static int lubbock_mci_get_ro(struct device *dev)
static int magician_mci_init(struct device *dev,
irq_handler_t detect_irq, void *data)
{
- return request_irq(IRQ_MAGICIAN_SD, detect_irq,
- IRQF_DISABLED | IRQF_SAMPLE_RANDOM,
- "mmc card detect", data);
+ return request_irq(IRQ_MAGICIAN_SD, detect_irq, IRQF_DISABLED,
+ "mmc card detect", data);
}
static void magician_mci_exit(struct device *dev, void *data)
int err;
err = request_irq(TRIZEPS4_MMC_IRQ, mci_detect_int,
- IRQF_DISABLED | IRQF_TRIGGER_RISING | IRQF_SAMPLE_RANDOM,
- "MMC card detect", data);
+ IRQF_DISABLED | IRQF_TRIGGER_RISING,
+ "MMC card detect", data);
if (err) {
printk(KERN_ERR "trizeps4_mci_init: MMC/SD: can't request"
"MMC card detect IRQ\n");
#include <linux/ioport.h>
#include <linux/kernel_stat.h>
#include <linux/ptrace.h>
-#include <linux/random.h> /* for rand_initialize_irq() */
#include <linux/signal.h>
#include <linux/smp.h>
#include <linux/threads.h>
snprintf(lp->rx_irq_name, LDC_IRQ_NAME_MAX, "%s RX", name);
snprintf(lp->tx_irq_name, LDC_IRQ_NAME_MAX, "%s TX", name);
- err = request_irq(lp->cfg.rx_irq, ldc_rx,
- IRQF_SAMPLE_RANDOM | IRQF_DISABLED,
+ err = request_irq(lp->cfg.rx_irq, ldc_rx, IRQF_DISABLED,
lp->rx_irq_name, lp);
if (err)
return err;
- err = request_irq(lp->cfg.tx_irq, ldc_tx,
- IRQF_SAMPLE_RANDOM | IRQF_DISABLED,
+ err = request_irq(lp->cfg.tx_irq, ldc_tx, IRQF_DISABLED,
lp->tx_irq_name, lp);
if (err) {
free_irq(lp->cfg.rx_irq, lp);
int line_setup_irq(int fd, int input, int output, struct line *line, void *data)
{
const struct line_driver *driver = line->driver;
- int err = 0, flags = IRQF_SHARED | IRQF_SAMPLE_RANDOM;
+ int err = 0;
if (input)
err = um_request_irq(driver->read_irq, fd, IRQ_READ,
- line_interrupt, flags,
- driver->read_irq_name, data);
+ line_interrupt, IRQF_SHARED,
+ driver->read_irq_name, data);
if (err)
return err;
if (output)
err = um_request_irq(driver->write_irq, fd, IRQ_WRITE,
- line_write_interrupt, flags,
- driver->write_irq_name, data);
+ line_write_interrupt, IRQF_SHARED,
+ driver->write_irq_name, data);
return err;
}
.stack = stack });
if (um_request_irq(WINCH_IRQ, fd, IRQ_READ, winch_interrupt,
- IRQF_SHARED | IRQF_SAMPLE_RANDOM,
- "winch", winch) < 0) {
+ IRQF_SHARED, "winch", winch) < 0) {
printk(KERN_ERR "register_winch_irq - failed to register "
"IRQ\n");
goto out_free;
register_reboot_notifier(&reboot_notifier);
err = um_request_irq(MCONSOLE_IRQ, sock, IRQ_READ, mconsole_interrupt,
- IRQF_SHARED | IRQF_SAMPLE_RANDOM,
- "mconsole", (void *)sock);
+ IRQF_SHARED, "mconsole", (void *)sock);
if (err) {
printk(KERN_ERR "Failed to get IRQ for management console\n");
goto out;
.port = port });
if (um_request_irq(TELNETD_IRQ, socket[0], IRQ_READ, pipe_interrupt,
- IRQF_SHARED | IRQF_SAMPLE_RANDOM,
- "telnetd", conn)) {
+ IRQF_SHARED, "telnetd", conn)) {
printk(KERN_ERR "port_accept : failed to get IRQ for "
"telnetd\n");
goto out_free;
}
if (um_request_irq(ACCEPT_IRQ, fd, IRQ_READ, port_interrupt,
- IRQF_SHARED | IRQF_SAMPLE_RANDOM,
- "port", port)) {
+ IRQF_SHARED, "port", port)) {
printk(KERN_ERR "Failed to get IRQ for port %d\n", port_num);
goto out_close;
}
random_fd = err;
err = um_request_irq(RANDOM_IRQ, random_fd, IRQ_READ, random_interrupt,
- IRQF_SAMPLE_RANDOM, "random",
- NULL);
+ 0, "random", NULL);
if (err)
goto err_out_cleanup_hw;
init_completion(&data->ready);
err = um_request_irq(XTERM_IRQ, socket, IRQ_READ, xterm_interrupt,
- IRQF_SHARED | IRQF_SAMPLE_RANDOM,
- "xterm", data);
+ IRQF_SHARED, "xterm", data);
if (err) {
printk(KERN_ERR "xterm_fd : failed to get IRQ for xterm, "
"err = %d\n", err);
int err;
err = um_request_irq(SIGIO_WRITE_IRQ, fd, IRQ_READ, sigio_interrupt,
- IRQF_SAMPLE_RANDOM, "write sigio",
- NULL);
+ 0, "write sigio", NULL);
if (err) {
printk(KERN_ERR "write_sigio_irq : um_request_irq failed, "
"err = %d\n", err);
if (err)
goto fail;
- err = bind_evtchn_to_irqhandler(info->evtchn,
- blkif_interrupt,
- IRQF_SAMPLE_RANDOM, "blkif", info);
+ err = bind_evtchn_to_irqhandler(info->evtchn, blkif_interrupt, 0,
+ "blkif", info);
if (err <= 0) {
xenbus_dev_fatal(dev, err,
"bind_evtchn_to_irqhandler failed");
* The current exported interfaces for gathering environmental noise
* from the devices are:
*
+ * void add_device_randomness(const void *buf, unsigned int size);
* void add_input_randomness(unsigned int type, unsigned int code,
* unsigned int value);
- * void add_interrupt_randomness(int irq);
+ * void add_interrupt_randomness(int irq, int irq_flags);
* void add_disk_randomness(struct gendisk *disk);
*
+ * add_device_randomness() is for adding data to the random pool that
+ * is likely to differ between two devices (or possibly even per boot).
+ * This would be things like MAC addresses or serial numbers, or the
+ * read-out of the RTC. This does *not* add any actual entropy to the
+ * pool, but it initializes the pool to different values for devices
+ * that might otherwise be identical and have very little entropy
+ * available to them (particularly common in the embedded world).
+ *
* add_input_randomness() uses the input layer interrupt timing, as well as
* the event type information from the hardware.
*
- * add_interrupt_randomness() uses the inter-interrupt timing as random
- * inputs to the entropy pool. Note that not all interrupts are good
- * sources of randomness! For example, the timer interrupts is not a
- * good choice, because the periodicity of the interrupts is too
- * regular, and hence predictable to an attacker. Network Interface
- * Controller interrupts are a better measure, since the timing of the
- * NIC interrupts are more unpredictable.
+ * add_interrupt_randomness() uses the interrupt timing as random
+ * inputs to the entropy pool. Using the cycle counters and the irq source
+ * as inputs, it feeds the randomness roughly once a second.
*
* add_disk_randomness() uses what amounts to the seek time of block
* layer request events, on a per-disk_devt basis, as input to the
#include <linux/percpu.h>
#include <linux/cryptohash.h>
#include <linux/fips.h>
+#include <linux/ptrace.h>
+#include <linux/kmemcheck.h>
#ifdef CONFIG_GENERIC_HARDIRQS
# include <linux/irq.h>
#include <asm/processor.h>
#include <asm/uaccess.h>
#include <asm/irq.h>
+#include <asm/irq_regs.h>
#include <asm/io.h>
+#define CREATE_TRACE_POINTS
+#include <trace/events/random.h>
+
/*
* Configuration information
*/
#define SEC_XFER_SIZE 512
#define EXTRACT_SIZE 10
+#define LONGS(x) (((x) + sizeof(unsigned long) - 1)/sizeof(unsigned long))
+
/*
* The minimum number of bits of entropy before we wake up a read on
* /dev/random. Should be enough to do a significant reseed.
/* read-write data: */
spinlock_t lock;
unsigned add_ptr;
+ unsigned input_rotate;
int entropy_count;
- int input_rotate;
+ int entropy_total;
+ unsigned int initialized:1;
__u8 last_data[EXTRACT_SIZE];
};
.pool = nonblocking_pool_data
};
+static __u32 const twist_table[8] = {
+ 0x00000000, 0x3b6e20c8, 0x76dc4190, 0x4db26158,
+ 0xedb88320, 0xd6d6a3e8, 0x9b64c2b0, 0xa00ae278 };
+
/*
* This function adds bytes into the entropy "pool". It does not
* update the entropy estimate. The caller should call
* it's cheap to do so and helps slightly in the expected case where
* the entropy is concentrated in the low-order bits.
*/
-static void mix_pool_bytes_extract(struct entropy_store *r, const void *in,
- int nbytes, __u8 out[64])
+static void _mix_pool_bytes(struct entropy_store *r, const void *in,
+ int nbytes, __u8 out[64])
{
- static __u32 const twist_table[8] = {
- 0x00000000, 0x3b6e20c8, 0x76dc4190, 0x4db26158,
- 0xedb88320, 0xd6d6a3e8, 0x9b64c2b0, 0xa00ae278 };
unsigned long i, j, tap1, tap2, tap3, tap4, tap5;
int input_rotate;
int wordmask = r->poolinfo->poolwords - 1;
const char *bytes = in;
__u32 w;
- unsigned long flags;
- /* Taps are constant, so we can load them without holding r->lock. */
tap1 = r->poolinfo->tap1;
tap2 = r->poolinfo->tap2;
tap3 = r->poolinfo->tap3;
tap4 = r->poolinfo->tap4;
tap5 = r->poolinfo->tap5;
- spin_lock_irqsave(&r->lock, flags);
- input_rotate = r->input_rotate;
- i = r->add_ptr;
+ smp_rmb();
+ input_rotate = ACCESS_ONCE(r->input_rotate);
+ i = ACCESS_ONCE(r->add_ptr);
/* mix one byte at a time to simplify size handling and churn faster */
while (nbytes--) {
input_rotate += i ? 7 : 14;
}
- r->input_rotate = input_rotate;
- r->add_ptr = i;
+ ACCESS_ONCE(r->input_rotate) = input_rotate;
+ ACCESS_ONCE(r->add_ptr) = i;
+ smp_wmb();
if (out)
for (j = 0; j < 16; j++)
((__u32 *)out)[j] = r->pool[(i - j) & wordmask];
+}
+
+static void __mix_pool_bytes(struct entropy_store *r, const void *in,
+ int nbytes, __u8 out[64])
+{
+ trace_mix_pool_bytes_nolock(r->name, nbytes, _RET_IP_);
+ _mix_pool_bytes(r, in, nbytes, out);
+}
+
+static void mix_pool_bytes(struct entropy_store *r, const void *in,
+ int nbytes, __u8 out[64])
+{
+ unsigned long flags;
+ trace_mix_pool_bytes(r->name, nbytes, _RET_IP_);
+ spin_lock_irqsave(&r->lock, flags);
+ _mix_pool_bytes(r, in, nbytes, out);
spin_unlock_irqrestore(&r->lock, flags);
}
-static void mix_pool_bytes(struct entropy_store *r, const void *in, int bytes)
+struct fast_pool {
+ __u32 pool[4];
+ unsigned long last;
+ unsigned short count;
+ unsigned char rotate;
+ unsigned char last_timer_intr;
+};
+
+/*
+ * This is a fast mixing routine used by the interrupt randomness
+ * collector. It's hardcoded for an 128 bit pool and assumes that any
+ * locks that might be needed are taken by the caller.
+ */
+static void fast_mix(struct fast_pool *f, const void *in, int nbytes)
{
- mix_pool_bytes_extract(r, in, bytes, NULL);
+ const char *bytes = in;
+ __u32 w;
+ unsigned i = f->count;
+ unsigned input_rotate = f->rotate;
+
+ while (nbytes--) {
+ w = rol32(*bytes++, input_rotate & 31) ^ f->pool[i & 3] ^
+ f->pool[(i + 1) & 3];
+ f->pool[i & 3] = (w >> 3) ^ twist_table[w & 7];
+ input_rotate += (i++ & 3) ? 7 : 14;
+ }
+ f->count = i;
+ f->rotate = input_rotate;
}
/*
*/
static void credit_entropy_bits(struct entropy_store *r, int nbits)
{
- unsigned long flags;
- int entropy_count;
+ int entropy_count, orig;
if (!nbits)
return;
- spin_lock_irqsave(&r->lock, flags);
-
DEBUG_ENT("added %d entropy credits to %s\n", nbits, r->name);
- entropy_count = r->entropy_count;
+retry:
+ entropy_count = orig = ACCESS_ONCE(r->entropy_count);
entropy_count += nbits;
+
if (entropy_count < 0) {
DEBUG_ENT("negative entropy/overflow\n");
entropy_count = 0;
} else if (entropy_count > r->poolinfo->POOLBITS)
entropy_count = r->poolinfo->POOLBITS;
- r->entropy_count = entropy_count;
+ if (cmpxchg(&r->entropy_count, orig, entropy_count) != orig)
+ goto retry;
+
+ if (!r->initialized && nbits > 0) {
+ r->entropy_total += nbits;
+ if (r->entropy_total > 128)
+ r->initialized = 1;
+ }
+
+ trace_credit_entropy_bits(r->name, nbits, entropy_count,
+ r->entropy_total, _RET_IP_);
/* should we wake readers? */
if (r == &input_pool && entropy_count >= random_read_wakeup_thresh) {
wake_up_interruptible(&random_read_wait);
kill_fasync(&fasync, SIGIO, POLL_IN);
}
- spin_unlock_irqrestore(&r->lock, flags);
}
/*********************************************************************
unsigned dont_count_entropy:1;
};
-#ifndef CONFIG_GENERIC_HARDIRQS
-
-static struct timer_rand_state *irq_timer_state[NR_IRQS];
-
-static struct timer_rand_state *get_timer_rand_state(unsigned int irq)
-{
- return irq_timer_state[irq];
-}
-
-static void set_timer_rand_state(unsigned int irq,
- struct timer_rand_state *state)
-{
- irq_timer_state[irq] = state;
-}
-
-#else
-
-static struct timer_rand_state *get_timer_rand_state(unsigned int irq)
-{
- struct irq_desc *desc;
-
- desc = irq_to_desc(irq);
-
- return desc->timer_rand_state;
-}
-
-static void set_timer_rand_state(unsigned int irq,
- struct timer_rand_state *state)
+/*
+ * Add device- or boot-specific data to the input and nonblocking
+ * pools to help initialize them to unique values.
+ *
+ * None of this adds any entropy, it is meant to avoid the
+ * problem of the nonblocking pool having similar initial state
+ * across largely identical devices.
+ */
+void add_device_randomness(const void *buf, unsigned int size)
{
- struct irq_desc *desc;
+ unsigned long time = get_cycles() ^ jiffies;
- desc = irq_to_desc(irq);
-
- desc->timer_rand_state = state;
+ mix_pool_bytes(&input_pool, buf, size, NULL);
+ mix_pool_bytes(&input_pool, &time, sizeof(time), NULL);
+ mix_pool_bytes(&nonblocking_pool, buf, size, NULL);
+ mix_pool_bytes(&nonblocking_pool, &time, sizeof(time), NULL);
}
-#endif
+EXPORT_SYMBOL(add_device_randomness);
static struct timer_rand_state input_timer_state;
goto out;
sample.jiffies = jiffies;
-
- /* Use arch random value, fall back to cycles */
- if (!arch_get_random_int(&sample.cycles))
- sample.cycles = get_cycles();
-
+ sample.cycles = get_cycles();
sample.num = num;
- mix_pool_bytes(&input_pool, &sample, sizeof(sample));
+ mix_pool_bytes(&input_pool, &sample, sizeof(sample), NULL);
/*
* Calculate number of bits of randomness we probably added.
}
EXPORT_SYMBOL_GPL(add_input_randomness);
-void add_interrupt_randomness(int irq)
+static DEFINE_PER_CPU(struct fast_pool, irq_randomness);
+
+void add_interrupt_randomness(int irq, int irq_flags)
{
- struct timer_rand_state *state;
+ struct entropy_store *r;
+ struct fast_pool *fast_pool = &__get_cpu_var(irq_randomness);
+ struct pt_regs *regs = get_irq_regs();
+ unsigned long now = jiffies;
+ __u32 input[4], cycles = get_cycles();
+
+ input[0] = cycles ^ jiffies;
+ input[1] = irq;
+ if (regs) {
+ __u64 ip = instruction_pointer(regs);
+ input[2] = ip;
+ input[3] = ip >> 32;
+ }
- state = get_timer_rand_state(irq);
+ fast_mix(fast_pool, input, sizeof(input));
- if (state == NULL)
+ if ((fast_pool->count & 1023) &&
+ !time_after(now, fast_pool->last + HZ))
return;
- DEBUG_ENT("irq event %d\n", irq);
- add_timer_randomness(state, 0x100 + irq);
+ fast_pool->last = now;
+
+ r = nonblocking_pool.initialized ? &input_pool : &nonblocking_pool;
+ __mix_pool_bytes(r, &fast_pool->pool, sizeof(fast_pool->pool), NULL);
+ /*
+ * If we don't have a valid cycle counter, and we see
+ * back-to-back timer interrupts, then skip giving credit for
+ * any entropy.
+ */
+ if (cycles == 0) {
+ if (irq_flags & __IRQF_TIMER) {
+ if (fast_pool->last_timer_intr)
+ return;
+ fast_pool->last_timer_intr = 1;
+ } else
+ fast_pool->last_timer_intr = 0;
+ }
+ credit_entropy_bits(r, 1);
}
#ifdef CONFIG_BLOCK
*/
static void xfer_secondary_pool(struct entropy_store *r, size_t nbytes)
{
- __u32 tmp[OUTPUT_POOL_WORDS];
+ __u32 tmp[OUTPUT_POOL_WORDS];
if (r->pull && r->entropy_count < nbytes * 8 &&
r->entropy_count < r->poolinfo->POOLBITS) {
bytes = extract_entropy(r->pull, tmp, bytes,
random_read_wakeup_thresh / 8, rsvd);
- mix_pool_bytes(r, tmp, bytes);
+ mix_pool_bytes(r, tmp, bytes, NULL);
credit_entropy_bits(r, bytes*8);
}
}
static void extract_buf(struct entropy_store *r, __u8 *out)
{
int i;
- __u32 hash[5], workspace[SHA_WORKSPACE_WORDS];
+ union {
+ __u32 w[5];
+ unsigned long l[LONGS(EXTRACT_SIZE)];
+ } hash;
+ __u32 workspace[SHA_WORKSPACE_WORDS];
__u8 extract[64];
+ unsigned long flags;
/* Generate a hash across the pool, 16 words (512 bits) at a time */
- sha_init(hash);
+ sha_init(hash.w);
+ spin_lock_irqsave(&r->lock, flags);
for (i = 0; i < r->poolinfo->poolwords; i += 16)
- sha_transform(hash, (__u8 *)(r->pool + i), workspace);
+ sha_transform(hash.w, (__u8 *)(r->pool + i), workspace);
/*
* We mix the hash back into the pool to prevent backtracking
* brute-forcing the feedback as hard as brute-forcing the
* hash.
*/
- mix_pool_bytes_extract(r, hash, sizeof(hash), extract);
+ __mix_pool_bytes(r, hash.w, sizeof(hash.w), extract);
+ spin_unlock_irqrestore(&r->lock, flags);
/*
* To avoid duplicates, we atomically extract a portion of the
* pool while mixing, and hash one final time.
*/
- sha_transform(hash, extract, workspace);
+ sha_transform(hash.w, extract, workspace);
memset(extract, 0, sizeof(extract));
memset(workspace, 0, sizeof(workspace));
* pattern, we fold it in half. Thus, we always feed back
* twice as much data as we output.
*/
- hash[0] ^= hash[3];
- hash[1] ^= hash[4];
- hash[2] ^= rol32(hash[2], 16);
- memcpy(out, hash, EXTRACT_SIZE);
- memset(hash, 0, sizeof(hash));
+ hash.w[0] ^= hash.w[3];
+ hash.w[1] ^= hash.w[4];
+ hash.w[2] ^= rol32(hash.w[2], 16);
+
+ /*
+ * If we have a architectural hardware random number
+ * generator, mix that in, too.
+ */
+ for (i = 0; i < LONGS(EXTRACT_SIZE); i++) {
+ unsigned long v;
+ if (!arch_get_random_long(&v))
+ break;
+ hash.l[i] ^= v;
+ }
+
+ memcpy(out, &hash, EXTRACT_SIZE);
+ memset(&hash, 0, sizeof(hash));
}
static ssize_t extract_entropy(struct entropy_store *r, void *buf,
- size_t nbytes, int min, int reserved)
+ size_t nbytes, int min, int reserved)
{
ssize_t ret = 0, i;
__u8 tmp[EXTRACT_SIZE];
- unsigned long flags;
+ trace_extract_entropy(r->name, nbytes, r->entropy_count, _RET_IP_);
xfer_secondary_pool(r, nbytes);
nbytes = account(r, nbytes, min, reserved);
extract_buf(r, tmp);
if (fips_enabled) {
+ unsigned long flags;
+
spin_lock_irqsave(&r->lock, flags);
if (!memcmp(tmp, r->last_data, EXTRACT_SIZE))
panic("Hardware RNG duplicated output!\n");
ssize_t ret = 0, i;
__u8 tmp[EXTRACT_SIZE];
+ trace_extract_entropy_user(r->name, nbytes, r->entropy_count, _RET_IP_);
xfer_secondary_pool(r, nbytes);
nbytes = account(r, nbytes, 0, 0);
/*
* This function is the exported kernel interface. It returns some
- * number of good random numbers, suitable for seeding TCP sequence
- * numbers, etc.
+ * number of good random numbers, suitable for key generation, seeding
+ * TCP sequence numbers, etc. It does not use the hw random number
+ * generator, if available; use get_random_bytes_arch() for that.
*/
void get_random_bytes(void *buf, int nbytes)
+{
+ extract_entropy(&nonblocking_pool, buf, nbytes, 0, 0);
+}
+EXPORT_SYMBOL(get_random_bytes);
+
+/*
+ * This function will use the architecture-specific hardware random
+ * number generator if it is available. The arch-specific hw RNG will
+ * almost certainly be faster than what we can do in software, but it
+ * is impossible to verify that it is implemented securely (as
+ * opposed, to, say, the AES encryption of a sequence number using a
+ * key known by the NSA). So it's useful if we need the speed, but
+ * only if we're willing to trust the hardware manufacturer not to
+ * have put in a back door.
+ */
+void get_random_bytes_arch(void *buf, int nbytes)
{
char *p = buf;
+ trace_get_random_bytes(nbytes, _RET_IP_);
while (nbytes) {
unsigned long v;
int chunk = min(nbytes, (int)sizeof(unsigned long));
-
+
if (!arch_get_random_long(&v))
break;
nbytes -= chunk;
}
- extract_entropy(&nonblocking_pool, p, nbytes, 0, 0);
+ if (nbytes)
+ extract_entropy(&nonblocking_pool, p, nbytes, 0, 0);
}
-EXPORT_SYMBOL(get_random_bytes);
+EXPORT_SYMBOL(get_random_bytes_arch);
+
/*
* init_std_data - initialize pool with system data
static void init_std_data(struct entropy_store *r)
{
int i;
- ktime_t now;
- unsigned long flags;
+ ktime_t now = ktime_get_real();
+ unsigned long rv;
- spin_lock_irqsave(&r->lock, flags);
r->entropy_count = 0;
- spin_unlock_irqrestore(&r->lock, flags);
-
- now = ktime_get_real();
- mix_pool_bytes(r, &now, sizeof(now));
- for (i = r->poolinfo->POOLBYTES; i > 0; i -= sizeof flags) {
- if (!arch_get_random_long(&flags))
+ r->entropy_total = 0;
+ mix_pool_bytes(r, &now, sizeof(now), NULL);
+ for (i = r->poolinfo->POOLBYTES; i > 0; i -= sizeof(rv)) {
+ if (!arch_get_random_long(&rv))
break;
- mix_pool_bytes(r, &flags, sizeof(flags));
+ mix_pool_bytes(r, &rv, sizeof(rv), NULL);
}
- mix_pool_bytes(r, utsname(), sizeof(*(utsname())));
+ mix_pool_bytes(r, utsname(), sizeof(*(utsname())), NULL);
}
+/*
+ * Note that setup_arch() may call add_device_randomness()
+ * long before we get here. This allows seeding of the pools
+ * with some platform dependent data very early in the boot
+ * process. But it limits our options here. We must use
+ * statically allocated structures that already have all
+ * initializations complete at compile time. We should also
+ * take care not to overwrite the precious per platform data
+ * we were given.
+ */
static int rand_initialize(void)
{
init_std_data(&input_pool);
}
module_init(rand_initialize);
-void rand_initialize_irq(int irq)
-{
- struct timer_rand_state *state;
-
- state = get_timer_rand_state(irq);
-
- if (state)
- return;
-
- /*
- * If kzalloc returns null, we just won't use that entropy
- * source.
- */
- state = kzalloc(sizeof(struct timer_rand_state), GFP_KERNEL);
- if (state)
- set_timer_rand_state(irq, state);
-}
-
#ifdef CONFIG_BLOCK
void rand_initialize_disk(struct gendisk *disk)
{
count -= bytes;
p += bytes;
- mix_pool_bytes(r, buf, bytes);
+ mix_pool_bytes(r, buf, bytes, NULL);
cond_resched();
}
}
static int sysctl_poolsize = INPUT_POOL_WORDS * 32;
+extern ctl_table random_table[];
ctl_table random_table[] = {
{
.procname = "poolsize",
* 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);
+static DEFINE_PER_CPU(__u32 [MD5_DIGEST_WORDS], get_random_int_hash);
unsigned int get_random_int(void)
{
__u32 *hash;
sprintf(p->irq_name, "%s-%d", irq_name, index);
- return request_irq(p->irq, handler, IRQF_SAMPLE_RANDOM,
- p->irq_name, p);
+ return request_irq(p->irq, handler, 0, p->irq_name, p);
}
static struct kmem_cache *queue_cache[2];
#include <linux/dmi.h>
#include <linux/efi.h>
#include <linux/bootmem.h>
+#include <linux/random.h>
#include <asm/dmi.h>
/*
dmi_table(buf, dmi_len, dmi_num, decode, NULL);
+ add_device_randomness(buf, dmi_len);
+
dmi_iounmap(buf, dmi_len);
return 0;
}
if (ret)
goto err_cleanup;
- ret = request_irq(irq, vmbus_isr, IRQF_SAMPLE_RANDOM,
- driver_name, hv_acpi_dev);
+ ret = request_irq(irq, vmbus_isr, 0, driver_name, hv_acpi_dev);
if (ret != 0) {
pr_err("Unable to request IRQ %d\n",
pmcmsptwi_data.irq = platform_get_irq(pldev, 0);
if (pmcmsptwi_data.irq) {
rc = request_irq(pmcmsptwi_data.irq, &pmcmsptwi_interrupt,
- IRQF_SHARED | IRQF_SAMPLE_RANDOM,
- pldev->name, &pmcmsptwi_data);
+ IRQF_SHARED, pldev->name, &pmcmsptwi_data);
if (rc == 0) {
/*
* Enable 'DONE' interrupt only.
#endif
errstr = "IRQ not available for";
- if (request_irq(hp_sdc.irq, &hp_sdc_isr, IRQF_SHARED|IRQF_SAMPLE_RANDOM,
+ if (request_irq(hp_sdc.irq, &hp_sdc_isr, IRQF_SHARED,
"HP SDC", &hp_sdc))
goto err1;
u32 fatevent;
int err;
- add_interrupt_randomness(irq);
-
err = ab3100_get_register_page_interruptible(ab3100, AB3100_EVENTA1,
event_regs, 3);
if (err)
IRQF_ONESHOT, "ab3100-core", ab3100);
if (err)
goto exit_no_irq;
- /* This real unpredictable IRQ is of course sampled for entropy */
- rand_initialize_irq(client->irq);
err = abx500_register_ops(&client->dev, &ab3100_ops);
if (err)
*/
if (client->irq > 0) {
status = request_irq(client->irq, tps65010_irq,
- IRQF_SAMPLE_RANDOM | IRQF_TRIGGER_FALLING,
- DRIVER_NAME, tps);
+ IRQF_TRIGGER_FALLING, DRIVER_NAME, tps);
if (status < 0) {
dev_dbg(&client->dev, "can't get IRQ %d, err %d\n",
client->irq, status);
#include <linux/bcd.h>
#include <linux/delay.h>
#include <linux/mfd/core.h>
+#include <linux/random.h>
#include <linux/mfd/wm831x/core.h>
#include <linux/mfd/wm831x/otp.h>
int wm831x_otp_init(struct wm831x *wm831x)
{
+ char uuid[WM831X_UNIQUE_ID_LEN];
int ret;
ret = device_create_file(wm831x->dev, &dev_attr_unique_id);
dev_err(wm831x->dev, "Unique ID attribute not created: %d\n",
ret);
+ ret = wm831x_unique_id_read(wm831x, uuid);
+ if (ret == 0)
+ add_device_randomness(uuid, sizeof(uuid));
+ else
+ dev_err(wm831x->dev, "Failed to read UUID: %d\n", ret);
+
return ret;
}
static inline unsigned int get_irq_flags(struct resource *res)
{
- unsigned int flags = IRQF_SAMPLE_RANDOM | IRQF_SHARED;
-
- flags |= res->flags & IRQF_TRIGGER_MASK;
-
- return flags;
+ return IRQF_SHARED | (res->flags & IRQF_TRIGGER_MASK);
}
static struct device *dev;
#include <linux/mfd/wm831x/core.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
-
+#include <linux/random.h>
/*
* R16416 (0x4020) - RTC Write Counter
unsigned int alarm_enabled:1;
};
+static void wm831x_rtc_add_randomness(struct wm831x *wm831x)
+{
+ int ret;
+ u16 reg;
+
+ /*
+ * The write counter contains a pseudo-random number which is
+ * regenerated every time we set the RTC so it should be a
+ * useful per-system source of entropy.
+ */
+ ret = wm831x_reg_read(wm831x, WM831X_RTC_WRITE_COUNTER);
+ if (ret >= 0) {
+ reg = ret;
+ add_device_randomness(®, sizeof(reg));
+ } else {
+ dev_warn(wm831x->dev, "Failed to read RTC write counter: %d\n",
+ ret);
+ }
+}
+
/*
* Read current time and date in RTC
*/
alm_irq, ret);
}
+ wm831x_rtc_add_randomness(wm831x);
+
return 0;
err:
{
int ret;
- ret = request_irq(port->irq, ulite_isr,
- IRQF_SHARED | IRQF_SAMPLE_RANDOM, "uartlite", port);
+ ret = request_irq(port->irq, ulite_isr, IRQF_SHARED, "uartlite", port);
if (ret)
return ret;
#include <linux/kthread.h>
#include <linux/mutex.h>
#include <linux/freezer.h>
+#include <linux/random.h>
#include <asm/uaccess.h>
#include <asm/byteorder.h>
/* Tell the world! */
announce_device(udev);
+ if (udev->serial)
+ add_device_randomness(udev->serial, strlen(udev->serial));
+ if (udev->product)
+ add_device_randomness(udev->product, strlen(udev->product));
+ if (udev->manufacturer)
+ add_device_randomness(udev->manufacturer,
+ strlen(udev->manufacturer));
+
device_enable_async_suspend(&udev->dev);
/*
/* init to known state, then setup irqs */
udc_reset(dev);
udc_reinit (dev);
- if (request_irq(pdev->irq, goku_irq, IRQF_SHARED/*|IRQF_SAMPLE_RANDOM*/,
+ if (request_irq(pdev->irq, goku_irq, IRQF_SHARED,
driver_name, dev) != 0) {
DBG(dev, "request interrupt %d failed\n", pdev->irq);
retval = -EBUSY;
#ifdef CONFIG_ARCH_LUBBOCK
if (machine_is_lubbock()) {
- retval = request_irq(LUBBOCK_USB_DISC_IRQ,
- lubbock_vbus_irq,
- IRQF_SAMPLE_RANDOM,
- driver_name, dev);
+ retval = request_irq(LUBBOCK_USB_DISC_IRQ, lubbock_vbus_irq,
+ 0, driver_name, dev);
if (retval != 0) {
pr_err("%s: can't get irq %i, err %d\n",
driver_name, LUBBOCK_USB_DISC_IRQ, retval);
goto err_irq_lub;
}
- retval = request_irq(LUBBOCK_USB_IRQ,
- lubbock_vbus_irq,
- IRQF_SAMPLE_RANDOM,
- driver_name, dev);
+ retval = request_irq(LUBBOCK_USB_IRQ, lubbock_vbus_irq,
+ 0, driver_name, dev);
if (retval != 0) {
pr_err("%s: can't get irq %i, err %d\n",
driver_name, LUBBOCK_USB_IRQ, retval);
isp->irq_type = IRQF_TRIGGER_FALLING;
}
- isp->irq_type |= IRQF_SAMPLE_RANDOM;
status = request_irq(i2c->irq, isp1301_irq,
isp->irq_type, DRIVER_NAME, isp);
if (status < 0) {
*
* IRQF_DISABLED - keep irqs disabled when calling the action handler.
* DEPRECATED. This flag is a NOOP and scheduled to be removed
- * IRQF_SAMPLE_RANDOM - irq is used to feed the random generator
* IRQF_SHARED - allow sharing the irq among several devices
* IRQF_PROBE_SHARED - set by callers when they expect sharing mismatches to occur
* IRQF_TIMER - Flag to mark this interrupt as timer interrupt
* resume time.
*/
#define IRQF_DISABLED 0x00000020
-#define IRQF_SAMPLE_RANDOM 0x00000040
#define IRQF_SHARED 0x00000080
#define IRQF_PROBE_SHARED 0x00000100
#define __IRQF_TIMER 0x00000200
*/
struct irq_desc {
struct irq_data irq_data;
- struct timer_rand_state *timer_rand_state;
unsigned int __percpu *kstat_irqs;
irq_flow_handler_t handle_irq;
#ifdef CONFIG_IRQ_PREFLOW_FASTEOI
#ifdef __KERNEL__
-extern void rand_initialize_irq(int irq);
-
+extern void add_device_randomness(const void *, unsigned int);
extern void add_input_randomness(unsigned int type, unsigned int code,
unsigned int value);
-extern void add_interrupt_randomness(int irq);
+extern void add_interrupt_randomness(int irq, int irq_flags);
extern void get_random_bytes(void *buf, int nbytes);
+extern void get_random_bytes_arch(void *buf, int nbytes);
void generate_random_uuid(unsigned char uuid_out[16]);
#ifndef MODULE
--- /dev/null
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM random
+
+#if !defined(_TRACE_RANDOM_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_RANDOM_H
+
+#include <linux/writeback.h>
+#include <linux/tracepoint.h>
+
+DECLARE_EVENT_CLASS(random__mix_pool_bytes,
+ TP_PROTO(const char *pool_name, int bytes, unsigned long IP),
+
+ TP_ARGS(pool_name, bytes, IP),
+
+ TP_STRUCT__entry(
+ __field( const char *, pool_name )
+ __field( int, bytes )
+ __field(unsigned long, IP )
+ ),
+
+ TP_fast_assign(
+ __entry->pool_name = pool_name;
+ __entry->bytes = bytes;
+ __entry->IP = IP;
+ ),
+
+ TP_printk("%s pool: bytes %d caller %pF",
+ __entry->pool_name, __entry->bytes, (void *)__entry->IP)
+);
+
+DEFINE_EVENT(random__mix_pool_bytes, mix_pool_bytes,
+ TP_PROTO(const char *pool_name, int bytes, unsigned long IP),
+
+ TP_ARGS(pool_name, bytes, IP)
+);
+
+DEFINE_EVENT(random__mix_pool_bytes, mix_pool_bytes_nolock,
+ TP_PROTO(const char *pool_name, int bytes, unsigned long IP),
+
+ TP_ARGS(pool_name, bytes, IP)
+);
+
+TRACE_EVENT(credit_entropy_bits,
+ TP_PROTO(const char *pool_name, int bits, int entropy_count,
+ int entropy_total, unsigned long IP),
+
+ TP_ARGS(pool_name, bits, entropy_count, entropy_total, IP),
+
+ TP_STRUCT__entry(
+ __field( const char *, pool_name )
+ __field( int, bits )
+ __field( int, entropy_count )
+ __field( int, entropy_total )
+ __field(unsigned long, IP )
+ ),
+
+ TP_fast_assign(
+ __entry->pool_name = pool_name;
+ __entry->bits = bits;
+ __entry->entropy_count = entropy_count;
+ __entry->entropy_total = entropy_total;
+ __entry->IP = IP;
+ ),
+
+ TP_printk("%s pool: bits %d entropy_count %d entropy_total %d "
+ "caller %pF", __entry->pool_name, __entry->bits,
+ __entry->entropy_count, __entry->entropy_total,
+ (void *)__entry->IP)
+);
+
+TRACE_EVENT(get_random_bytes,
+ TP_PROTO(int nbytes, unsigned long IP),
+
+ TP_ARGS(nbytes, IP),
+
+ TP_STRUCT__entry(
+ __field( int, nbytes )
+ __field(unsigned long, IP )
+ ),
+
+ TP_fast_assign(
+ __entry->nbytes = nbytes;
+ __entry->IP = IP;
+ ),
+
+ TP_printk("nbytes %d caller %pF", __entry->nbytes, (void *)__entry->IP)
+);
+
+DECLARE_EVENT_CLASS(random__extract_entropy,
+ TP_PROTO(const char *pool_name, int nbytes, int entropy_count,
+ unsigned long IP),
+
+ TP_ARGS(pool_name, nbytes, entropy_count, IP),
+
+ TP_STRUCT__entry(
+ __field( const char *, pool_name )
+ __field( int, nbytes )
+ __field( int, entropy_count )
+ __field(unsigned long, IP )
+ ),
+
+ TP_fast_assign(
+ __entry->pool_name = pool_name;
+ __entry->nbytes = nbytes;
+ __entry->entropy_count = entropy_count;
+ __entry->IP = IP;
+ ),
+
+ TP_printk("%s pool: nbytes %d entropy_count %d caller %pF",
+ __entry->pool_name, __entry->nbytes, __entry->entropy_count,
+ (void *)__entry->IP)
+);
+
+
+DEFINE_EVENT(random__extract_entropy, extract_entropy,
+ TP_PROTO(const char *pool_name, int nbytes, int entropy_count,
+ unsigned long IP),
+
+ TP_ARGS(pool_name, nbytes, entropy_count, IP)
+);
+
+DEFINE_EVENT(random__extract_entropy, extract_entropy_user,
+ TP_PROTO(const char *pool_name, int nbytes, int entropy_count,
+ unsigned long IP),
+
+ TP_ARGS(pool_name, nbytes, entropy_count, IP)
+);
+
+
+
+#endif /* _TRACE_RANDOM_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action)
{
irqreturn_t retval = IRQ_NONE;
- unsigned int random = 0, irq = desc->irq_data.irq;
+ unsigned int flags = 0, irq = desc->irq_data.irq;
do {
irqreturn_t res;
/* Fall through to add to randomness */
case IRQ_HANDLED:
- random |= action->flags;
+ flags |= action->flags;
break;
default:
action = action->next;
} while (action);
- if (random & IRQF_SAMPLE_RANDOM)
- add_interrupt_randomness(irq);
+ add_interrupt_randomness(irq, flags);
if (!noirqdebug)
note_interrupt(irq, desc, retval);
return -ENOSYS;
if (!try_module_get(desc->owner))
return -ENODEV;
- /*
- * Some drivers like serial.c use request_irq() heavily,
- * so we have to be careful not to interfere with a
- * running system.
- */
- if (new->flags & IRQF_SAMPLE_RANDOM) {
- /*
- * This function might sleep, we want to call it first,
- * outside of the atomic block.
- * Yes, this might clear the entropy pool if the wrong
- * driver is attempted to be loaded, without actually
- * installing a new handler, but is this really a problem,
- * only the sysadmin is able to do this.
- */
- rand_initialize_irq(irq);
- }
/*
* Check whether the interrupt nests into another interrupt
* Flags:
*
* IRQF_SHARED Interrupt is shared
- * IRQF_SAMPLE_RANDOM The interrupt can be used for entropy
* IRQF_TRIGGER_* Specify active edge(s) or level
*
*/
net_dmaengine_get();
dev_set_rx_mode(dev);
dev_activate(dev);
+ add_device_randomness(dev->dev_addr, dev->addr_len);
}
return ret;
err = ops->ndo_set_mac_address(dev, sa);
if (!err)
call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
+ add_device_randomness(dev->dev_addr, dev->addr_len);
return err;
}
EXPORT_SYMBOL(dev_set_mac_address);
dev_init_scheduler(dev);
dev_hold(dev);
list_netdevice(dev);
+ add_device_randomness(dev->dev_addr, dev->addr_len);
/* Notify protocols, that a new device appeared. */
ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
goto errout;
send_addr_notify = 1;
modified = 1;
+ add_device_randomness(dev->dev_addr, dev->addr_len);
}
if (tb[IFLA_MTU]) {