diff options
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/Kconfig | 2 | ||||
| -rw-r--r-- | drivers/char/hw_random/Kconfig | 6 | ||||
| -rw-r--r-- | drivers/char/random.c | 244 | ||||
| -rw-r--r-- | drivers/char/tpm/Kconfig | 2 | ||||
| -rw-r--r-- | drivers/char/virtio_console.c | 4 |
5 files changed, 143 insertions, 115 deletions
diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig index 1386749b48ff..fbae63e3d304 100644 --- a/drivers/char/Kconfig +++ b/drivers/char/Kconfig @@ -408,7 +408,7 @@ config APPLICOM config SONYPI tristate "Sony Vaio Programmable I/O Control Device support" - depends on X86 && PCI && INPUT && !64BIT + depends on X86_32 && PCI && INPUT ---help--- This driver enables access to the Sony Programmable I/O Control Device which can be found in many (all ?) Sony Vaio laptops. diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig index 2f2b08457c67..244759bbd7b7 100644 --- a/drivers/char/hw_random/Kconfig +++ b/drivers/char/hw_random/Kconfig @@ -342,11 +342,11 @@ config HW_RANDOM_TPM If unsure, say Y. config HW_RANDOM_MSM - tristate "Qualcomm MSM Random Number Generator support" - depends on HW_RANDOM && ARCH_MSM + tristate "Qualcomm SoCs Random Number Generator support" + depends on HW_RANDOM && ARCH_QCOM ---help--- This driver provides kernel-side support for the Random Number - Generator hardware found on Qualcomm MSM SoCs. + Generator hardware found on Qualcomm SoCs. To compile this driver as a module, choose M here. the module will be called msm-rng. diff --git a/drivers/char/random.c b/drivers/char/random.c index 429b75bb60e8..6b75713d953a 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -295,17 +295,17 @@ * The minimum number of bits of entropy before we wake up a read on * /dev/random. Should be enough to do a significant reseed. */ -static int random_read_wakeup_thresh = 64; +static int random_read_wakeup_bits = 64; /* * If the entropy count falls under this number of bits, then we * should wake up processes which are selecting or polling on write * access to /dev/random. */ -static int random_write_wakeup_thresh = 28 * OUTPUT_POOL_WORDS; +static int random_write_wakeup_bits = 28 * OUTPUT_POOL_WORDS; /* - * The minimum number of seconds between urandom pool resending. We + * The minimum number of seconds between urandom pool reseeding. We * do this to limit the amount of entropy that can be drained from the * input pool even if there are heavy demands on /dev/urandom. */ @@ -322,7 +322,7 @@ static int random_min_urandom_seed = 60; * Register. (See M. Matsumoto & Y. Kurita, 1992. Twisted GFSR * generators. ACM Transactions on Modeling and Computer Simulation * 2(3):179-194. Also see M. Matsumoto & Y. Kurita, 1994. Twisted - * GFSR generators II. ACM Transactions on Mdeling and Computer + * GFSR generators II. ACM Transactions on Modeling and Computer * Simulation 4:254-266) * * Thanks to Colin Plumb for suggesting this. @@ -666,10 +666,10 @@ retry: r->entropy_total, _RET_IP_); if (r == &input_pool) { - int entropy_bytes = entropy_count >> ENTROPY_SHIFT; + int entropy_bits = entropy_count >> ENTROPY_SHIFT; /* should we wake readers? */ - if (entropy_bytes >= random_read_wakeup_thresh) { + if (entropy_bits >= random_read_wakeup_bits) { wake_up_interruptible(&random_read_wait); kill_fasync(&fasync, SIGIO, POLL_IN); } @@ -678,9 +678,9 @@ retry: * forth between them, until the output pools are 75% * full. */ - if (entropy_bytes > random_write_wakeup_thresh && + if (entropy_bits > random_write_wakeup_bits && r->initialized && - r->entropy_total >= 2*random_read_wakeup_thresh) { + r->entropy_total >= 2*random_read_wakeup_bits) { static struct entropy_store *last = &blocking_pool; struct entropy_store *other = &blocking_pool; @@ -844,6 +844,8 @@ void add_interrupt_randomness(int irq, int irq_flags) cycles_t cycles = random_get_entropy(); __u32 input[4], c_high, j_high; __u64 ip; + unsigned long seed; + int credit; c_high = (sizeof(cycles) > 4) ? cycles >> 32 : 0; j_high = (sizeof(now) > 4) ? now >> 32 : 0; @@ -862,20 +864,33 @@ void add_interrupt_randomness(int irq, int irq_flags) 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. + * any entropy, otherwise credit 1 bit. */ + credit = 1; if (cycles == 0) { if (irq_flags & __IRQF_TIMER) { if (fast_pool->last_timer_intr) - return; + credit = 0; fast_pool->last_timer_intr = 1; } else fast_pool->last_timer_intr = 0; } - credit_entropy_bits(r, 1); + + /* + * If we have architectural seed generator, produce a seed and + * add it to the pool. For the sake of paranoia count it as + * 50% entropic. + */ + if (arch_get_random_seed_long(&seed)) { + __mix_pool_bytes(r, &seed, sizeof(seed), NULL); + credit += sizeof(seed) * 4; + } + + credit_entropy_bits(r, credit); } #ifdef CONFIG_BLOCK @@ -924,19 +939,19 @@ static void _xfer_secondary_pool(struct entropy_store *r, size_t nbytes) { __u32 tmp[OUTPUT_POOL_WORDS]; - /* For /dev/random's pool, always leave two wakeup worth's BITS */ - int rsvd = r->limit ? 0 : random_read_wakeup_thresh/4; + /* For /dev/random's pool, always leave two wakeups' worth */ + int rsvd_bytes = r->limit ? 0 : random_read_wakeup_bits / 4; int bytes = nbytes; - /* pull at least as many as BYTES as wakeup BITS */ - bytes = max_t(int, bytes, random_read_wakeup_thresh / 8); + /* pull at least as much as a wakeup */ + bytes = max_t(int, bytes, random_read_wakeup_bits / 8); /* but never more than the buffer size */ bytes = min_t(int, bytes, sizeof(tmp)); trace_xfer_secondary_pool(r->name, bytes * 8, nbytes * 8, ENTROPY_BITS(r), ENTROPY_BITS(r->pull)); bytes = extract_entropy(r->pull, tmp, bytes, - random_read_wakeup_thresh / 8, rsvd); + random_read_wakeup_bits / 8, rsvd_bytes); mix_pool_bytes(r, tmp, bytes, NULL); credit_entropy_bits(r, bytes*8); } @@ -952,35 +967,22 @@ static void push_to_pool(struct work_struct *work) struct entropy_store *r = container_of(work, struct entropy_store, push_work); BUG_ON(!r); - _xfer_secondary_pool(r, random_read_wakeup_thresh/8); + _xfer_secondary_pool(r, random_read_wakeup_bits/8); trace_push_to_pool(r->name, r->entropy_count >> ENTROPY_SHIFT, r->pull->entropy_count >> ENTROPY_SHIFT); } /* - * These functions extracts randomness from the "entropy pool", and - * returns it in a buffer. - * - * The min parameter specifies the minimum amount we can pull before - * failing to avoid races that defeat catastrophic reseeding while the - * reserved parameter indicates how much entropy we must leave in the - * pool after each pull to avoid starving other readers. - * - * Note: extract_entropy() assumes that .poolwords is a multiple of 16 words. + * This function decides how many bytes to actually take from the + * given pool, and also debits the entropy count accordingly. */ - static size_t account(struct entropy_store *r, size_t nbytes, int min, int reserved) { - unsigned long flags; - int wakeup_write = 0; int have_bytes; int entropy_count, orig; size_t ibytes; - /* Hold lock while accounting */ - spin_lock_irqsave(&r->lock, flags); - BUG_ON(r->entropy_count > r->poolinfo->poolfracbits); /* Can we pull enough? */ @@ -988,29 +990,19 @@ retry: entropy_count = orig = ACCESS_ONCE(r->entropy_count); have_bytes = entropy_count >> (ENTROPY_SHIFT + 3); ibytes = nbytes; - if (have_bytes < min + reserved) { + /* If limited, never pull more than available */ + if (r->limit) + ibytes = min_t(size_t, ibytes, have_bytes - reserved); + if (ibytes < min) ibytes = 0; - } else { - /* If limited, never pull more than available */ - if (r->limit && ibytes + reserved >= have_bytes) - ibytes = have_bytes - reserved; - - if (have_bytes >= ibytes + reserved) - entropy_count -= ibytes << (ENTROPY_SHIFT + 3); - else - entropy_count = reserved << (ENTROPY_SHIFT + 3); - - if (cmpxchg(&r->entropy_count, orig, entropy_count) != orig) - goto retry; - - if ((r->entropy_count >> ENTROPY_SHIFT) - < random_write_wakeup_thresh) - wakeup_write = 1; - } - spin_unlock_irqrestore(&r->lock, flags); + entropy_count = max_t(int, 0, + entropy_count - (ibytes << (ENTROPY_SHIFT + 3))); + if (cmpxchg(&r->entropy_count, orig, entropy_count) != orig) + goto retry; trace_debit_entropy(r->name, 8 * ibytes); - if (wakeup_write) { + if (ibytes && + (r->entropy_count >> ENTROPY_SHIFT) < random_write_wakeup_bits) { wake_up_interruptible(&random_write_wait); kill_fasync(&fasync, SIGIO, POLL_OUT); } @@ -1018,6 +1010,12 @@ retry: return ibytes; } +/* + * This function does the actual extraction for extract_entropy and + * extract_entropy_user. + * + * Note: we assume that .poolwords is a multiple of 16 words. + */ static void extract_buf(struct entropy_store *r, __u8 *out) { int i; @@ -1029,23 +1027,23 @@ static void extract_buf(struct entropy_store *r, __u8 *out) __u8 extract[64]; unsigned long flags; - /* Generate a hash across the pool, 16 words (512 bits) at a time */ - sha_init(hash.w); - spin_lock_irqsave(&r->lock, flags); - for (i = 0; i < r->poolinfo->poolwords; i += 16) - sha_transform(hash.w, (__u8 *)(r->pool + i), workspace); - /* - * If we have a architectural hardware random number - * generator, mix that in, too. + * If we have an architectural hardware random number + * generator, use it for SHA's initial vector */ + sha_init(hash.w); for (i = 0; i < LONGS(20); i++) { unsigned long v; if (!arch_get_random_long(&v)) break; - hash.l[i] ^= v; + hash.l[i] = v; } + /* Generate a hash across the pool, 16 words (512 bits) at a time */ + spin_lock_irqsave(&r->lock, flags); + for (i = 0; i < r->poolinfo->poolwords; i += 16) + sha_transform(hash.w, (__u8 *)(r->pool + i), workspace); + /* * We mix the hash back into the pool to prevent backtracking * attacks (where the attacker knows the state of the pool @@ -1079,6 +1077,15 @@ static void extract_buf(struct entropy_store *r, __u8 *out) memset(&hash, 0, sizeof(hash)); } +/* + * This function extracts randomness from the "entropy pool", and + * returns it in a buffer. + * + * The min parameter specifies the minimum amount we can pull before + * failing to avoid races that defeat catastrophic reseeding while the + * reserved parameter indicates how much entropy we must leave in the + * pool after each pull to avoid starving other readers. + */ static ssize_t extract_entropy(struct entropy_store *r, void *buf, size_t nbytes, int min, int reserved) { @@ -1129,6 +1136,10 @@ static ssize_t extract_entropy(struct entropy_store *r, void *buf, return ret; } +/* + * This function extracts randomness from the "entropy pool", and + * returns it in a userspace buffer. + */ static ssize_t extract_entropy_user(struct entropy_store *r, void __user *buf, size_t nbytes) { @@ -1170,8 +1181,9 @@ static ssize_t extract_entropy_user(struct entropy_store *r, void __user *buf, /* * This function is the exported kernel interface. It returns some * 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. + * TCP sequence numbers, etc. It does not rely on the hardware random + * number generator. For random bytes direct from the hardware RNG + * (when available), use get_random_bytes_arch(). */ void get_random_bytes(void *buf, int nbytes) { @@ -1238,7 +1250,8 @@ static void init_std_data(struct entropy_store *r) r->last_pulled = jiffies; mix_pool_bytes(r, &now, sizeof(now), NULL); for (i = r->poolinfo->poolbytes; i > 0; i -= sizeof(rv)) { - if (!arch_get_random_long(&rv)) + if (!arch_get_random_seed_long(&rv) && + !arch_get_random_long(&rv)) rv = random_get_entropy(); mix_pool_bytes(r, &rv, sizeof(rv), NULL); } @@ -1281,56 +1294,71 @@ void rand_initialize_disk(struct gendisk *disk) } #endif -static ssize_t -random_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos) +/* + * Attempt an emergency refill using arch_get_random_seed_long(). + * + * As with add_interrupt_randomness() be paranoid and only + * credit the output as 50% entropic. + */ +static int arch_random_refill(void) { - ssize_t n, retval = 0, count = 0; + const unsigned int nlongs = 64; /* Arbitrary number */ + unsigned int n = 0; + unsigned int i; + unsigned long buf[nlongs]; - if (nbytes == 0) + if (!arch_has_random_seed()) return 0; - while (nbytes > 0) { - n = nbytes; - if (n > SEC_XFER_SIZE) - n = SEC_XFER_SIZE; + for (i = 0; i < nlongs; i++) { + if (arch_get_random_seed_long(&buf[n])) + n++; + } - n = extract_entropy_user(&blocking_pool, buf, n); + if (n) { + unsigned int rand_bytes = n * sizeof(unsigned long); - if (n < 0) { - retval = n; - break; - } + mix_pool_bytes(&input_pool, buf, rand_bytes, NULL); + credit_entropy_bits(&input_pool, rand_bytes*4); + } + return n; +} + +static ssize_t +random_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos) +{ + ssize_t n; + + if (nbytes == 0) + return 0; + + nbytes = min_t(size_t, nbytes, SEC_XFER_SIZE); + while (1) { + n = extract_entropy_user(&blocking_pool, buf, nbytes); + if (n < 0) + return n; trace_random_read(n*8, (nbytes-n)*8, ENTROPY_BITS(&blocking_pool), ENTROPY_BITS(&input_pool)); + if (n > 0) + return n; - if (n == 0) { - if (file->f_flags & O_NONBLOCK) { - retval = -EAGAIN; - break; - } - - wait_event_interruptible(random_read_wait, - ENTROPY_BITS(&input_pool) >= - random_read_wakeup_thresh); - - if (signal_pending(current)) { - retval = -ERESTARTSYS; - break; - } + /* Pool is (near) empty. Maybe wait and retry. */ + /* First try an emergency refill */ + if (arch_random_refill()) continue; - } - count += n; - buf += n; - nbytes -= n; - break; /* This break makes the device work */ - /* like a named pipe */ - } + if (file->f_flags & O_NONBLOCK) + return -EAGAIN; - return (count ? count : retval); + wait_event_interruptible(random_read_wait, + ENTROPY_BITS(&input_pool) >= + random_read_wakeup_bits); + if (signal_pending(current)) + return -ERESTARTSYS; + } } static ssize_t @@ -1358,9 +1386,9 @@ random_poll(struct file *file, poll_table * wait) poll_wait(file, &random_read_wait, wait); poll_wait(file, &random_write_wait, wait); mask = 0; - if (ENTROPY_BITS(&input_pool) >= random_read_wakeup_thresh) + if (ENTROPY_BITS(&input_pool) >= random_read_wakeup_bits) mask |= POLLIN | POLLRDNORM; - if (ENTROPY_BITS(&input_pool) < random_write_wakeup_thresh) + if (ENTROPY_BITS(&input_pool) < random_write_wakeup_bits) mask |= POLLOUT | POLLWRNORM; return mask; } @@ -1507,18 +1535,18 @@ EXPORT_SYMBOL(generate_random_uuid); #include <linux/sysctl.h> static int min_read_thresh = 8, min_write_thresh; -static int max_read_thresh = INPUT_POOL_WORDS * 32; +static int max_read_thresh = OUTPUT_POOL_WORDS * 32; static int max_write_thresh = INPUT_POOL_WORDS * 32; static char sysctl_bootid[16]; /* - * These functions is used to return both the bootid UUID, and random + * This function is used to return both the bootid UUID, and random * UUID. The difference is in whether table->data is NULL; if it is, * then a new UUID is generated and returned to the user. * - * If the user accesses this via the proc interface, it will be returned - * 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. + * If the user accesses this via the proc interface, the UUID will be + * returned as an ASCII string in the standard UUID format; if via the + * sysctl system call, as 16 bytes of binary data. */ static int proc_do_uuid(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) @@ -1583,7 +1611,7 @@ struct ctl_table random_table[] = { }, { .procname = "read_wakeup_threshold", - .data = &random_read_wakeup_thresh, + .data = &random_read_wakeup_bits, .maxlen = sizeof(int), .mode = 0644, .proc_handler = proc_dointvec_minmax, @@ -1592,7 +1620,7 @@ struct ctl_table random_table[] = { }, { .procname = "write_wakeup_threshold", - .data = &random_write_wakeup_thresh, + .data = &random_write_wakeup_bits, .maxlen = sizeof(int), .mode = 0644, .proc_handler = proc_dointvec_minmax, diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig index 1a65838888cd..c54cac3f8bc8 100644 --- a/drivers/char/tpm/Kconfig +++ b/drivers/char/tpm/Kconfig @@ -74,7 +74,7 @@ config TCG_NSC config TCG_ATMEL tristate "Atmel TPM Interface" - depends on PPC64 || HAS_IOPORT + depends on PPC64 || HAS_IOPORT_MAP ---help--- If you have a TPM security chip from Atmel say Yes and it will be accessible from within Linux. To compile this driver diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c index 6928d094451d..60aafb8a1f2e 100644 --- a/drivers/char/virtio_console.c +++ b/drivers/char/virtio_console.c @@ -901,9 +901,9 @@ static int pipe_to_sg(struct pipe_inode_info *pipe, struct pipe_buffer *buf, if (len + offset > PAGE_SIZE) len = PAGE_SIZE - offset; - src = buf->ops->map(pipe, buf, 1); + src = kmap_atomic(buf->page); memcpy(page_address(page) + offset, src + buf->offset, len); - buf->ops->unmap(pipe, buf, src); + kunmap_atomic(src); sg_set_page(&(sgl->sg[sgl->n]), page, len, offset); } |