diff --git a/share/man/man9/Makefile b/share/man/man9/Makefile index 21541908e218..695fa23cd2f3 100644 --- a/share/man/man9/Makefile +++ b/share/man/man9/Makefile @@ -1281,6 +1281,7 @@ MLINKS+=psignal.9 gsignal.9 \ MLINKS+=random.9 arc4rand.9 \ random.9 arc4random.9 \ random.9 read_random.9 \ + random.9 read_random_uio.9 \ random.9 srandom.9 MLINKS+=refcount.9 refcount_acquire.9 \ refcount.9 refcount_init.9 \ diff --git a/share/man/man9/random.9 b/share/man/man9/random.9 index 906b5e59679b..275359a6945b 100644 --- a/share/man/man9/random.9 +++ b/share/man/man9/random.9 @@ -26,7 +26,7 @@ .\" .\" $FreeBSD$ .\" " -.Dd June 30, 2015 +.Dd July 14, 2015 .Dt RANDOM 9 .Os .Sh NAME @@ -34,6 +34,7 @@ .Nm arc4random , .Nm random , .Nm read_random , +.Nm read_random_uio , .Nm srandom .Nd supply pseudo-random numbers .Sh SYNOPSIS @@ -50,6 +51,8 @@ .In sys/random.h .Ft int .Fn read_random "void *buffer" "int count" +.Ft int +.Fn read_random_uio "struct uio *uio" "bool nonblock" .Sh DESCRIPTION The .Fn random @@ -117,11 +120,27 @@ necessary to know that no entropy has been returned. .Pp +The +.Fn read_random_uio +function behaves identically to +.Xr read 2 +on +.Pa /dev/random . +The +.Fa uio +argument points to a buffer where random data should be stored. +This function only returns data if the the random device is seeded. +It blocks if unseeded, +except when the +.Fa nonblock +argument is true. +.Pp All the bits returned by .Fn random , -.Fn arc4rand +.Fn arc4rand , +.Fn read_random , and -.Fn read_random +.Fn read_random_uio are usable. For example, .Sq Li random()&01 @@ -168,6 +187,22 @@ The function returns the number of bytes placed in .Fa buffer . +.Pp +.Fn read_random_uio +returns zero when successful, +otherwise an error code is returned. +.Sh ERRORS +.Fn read_random_uio +may fail if: +.Bl -tag -width Er +.It Bq Er EFAULT +.Fa uio +points to an invalid memory region. +.It Bq Er EWOULDBLOCK +The random device is unseeded and +.Fa nonblock +is true. +.El .Sh AUTHORS .An Dan Moschuk wrote diff --git a/sys/compat/cloudabi/cloudabi_random.c b/sys/compat/cloudabi/cloudabi_random.c index bd644c316353..76a93604d299 100644 --- a/sys/compat/cloudabi/cloudabi_random.c +++ b/sys/compat/cloudabi/cloudabi_random.c @@ -26,13 +26,28 @@ #include __FBSDID("$FreeBSD$"); +#include +#include +#include + #include int cloudabi_sys_random_get(struct thread *td, struct cloudabi_sys_random_get_args *uap) { + struct iovec iov = { + .iov_base = uap->buf, + .iov_len = uap->nbyte + }; + struct uio uio = { + .uio_iov = &iov, + .uio_iovcnt = 1, + .uio_resid = iov.iov_len, + .uio_segflg = UIO_USERSPACE, + .uio_rw = UIO_READ, + .uio_td = td + }; - /* Not implemented. */ - return (ENOSYS); + return (read_random_uio(&uio, false)); } diff --git a/sys/dev/random/randomdev.c b/sys/dev/random/randomdev.c index e27b90957d09..f3339aa40827 100644 --- a/sys/dev/random/randomdev.c +++ b/sys/dev/random/randomdev.c @@ -151,6 +151,13 @@ static struct selinfo rsel; /* ARGSUSED */ static int randomdev_read(struct cdev *dev __unused, struct uio *uio, int flags) +{ + + return (read_random_uio(uio, (flags & O_NONBLOCK) != 0)); +} + +int +read_random_uio(struct uio *uio, bool nonblock) { uint8_t *random_buf; int error; diff --git a/sys/sys/random.h b/sys/sys/random.h index 920d36b09431..78a9955a0e10 100644 --- a/sys/sys/random.h +++ b/sys/sys/random.h @@ -31,7 +31,12 @@ #ifdef _KERNEL +#include + +struct uio; + u_int read_random(void *, u_int); +int read_random_uio(struct uio *, bool); /* * Note: if you add or remove members of random_entropy_source, remember to also update the