Add syscall getrandom

This commit is contained in:
Jianfeng Jiang 2023-06-12 17:12:15 +08:00 committed by Tate, Hongliang Tian
parent 3600a3a439
commit 5815f248fc
7 changed files with 136 additions and 3 deletions

22
Cargo.lock generated
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@ -302,6 +302,17 @@ version = "2.0.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "e6d5a32815ae3f33302d95fdcb2ce17862f8c65363dcfd29360480ba1001fc9c"
[[package]]
name = "getrandom"
version = "0.2.10"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "be4136b2a15dd319360be1c07d9933517ccf0be8f16bf62a3bee4f0d618df427"
dependencies = [
"cfg-if",
"libc",
"wasi",
]
[[package]]
name = "ghost"
version = "0.1.7"
@ -564,6 +575,7 @@ dependencies = [
"controlled",
"core2",
"cpio-decoder",
"getrandom",
"int-to-c-enum",
"intrusive-collections",
"jinux-block",
@ -650,9 +662,9 @@ dependencies = [
[[package]]
name = "libc"
version = "0.2.137"
version = "0.2.146"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "fc7fcc620a3bff7cdd7a365be3376c97191aeaccc2a603e600951e452615bf89"
checksum = "f92be4933c13fd498862a9e02a3055f8a8d9c039ce33db97306fd5a6caa7f29b"
[[package]]
name = "libflate"
@ -1130,6 +1142,12 @@ dependencies = [
"libc",
]
[[package]]
name = "wasi"
version = "0.11.0+wasi-snapshot-preview1"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
[[package]]
name = "winnow"
version = "0.3.3"

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@ -42,6 +42,7 @@ spin = "0.9.4"
vte = "0.10"
lru = "0.9.0"
log = "0.4"
getrandom = { version = "0.2.10", default-features = false, features = ["rdrand"] }
[dependencies.lazy_static]
version = "1.0"

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@ -1,9 +1,13 @@
mod null;
mod random;
pub mod tty;
mod urandom;
mod zero;
use crate::fs::device::{add_node, Device, DeviceId, DeviceType};
use crate::prelude::*;
pub use random::Random;
pub use urandom::Urandom;
/// Init the device node in fs, must be called after mounting rootfs.
pub fn init() -> Result<()> {
@ -14,5 +18,9 @@ pub fn init() -> Result<()> {
tty::init();
let tty = tty::get_n_tty().clone();
add_node(tty, "tty")?;
let random = Arc::new(random::Random);
add_node(random, "random")?;
let urandom = Arc::new(urandom::Urandom);
add_node(urandom, "urandom")?;
Ok(())
}

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@ -0,0 +1,36 @@
use crate::fs::device::{Device, DeviceId, DeviceType};
use crate::prelude::*;
pub struct Random;
impl Random {
pub fn getrandom(buf: &mut [u8]) -> Result<usize> {
getrandom::getrandom(buf)?;
Ok(buf.len())
}
}
impl Device for Random {
fn type_(&self) -> DeviceType {
DeviceType::CharDevice
}
fn id(&self) -> DeviceId {
// The same value as Linux
DeviceId::new(1, 8)
}
fn read(&self, buf: &mut [u8]) -> Result<usize> {
Self::getrandom(buf)
}
fn write(&self, buf: &[u8]) -> Result<usize> {
Ok(buf.len())
}
}
impl From<getrandom::Error> for Error {
fn from(value: getrandom::Error) -> Self {
Error::with_message(Errno::ENOSYS, "cannot generate random bytes")
}
}

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@ -0,0 +1,30 @@
use crate::fs::device::{Device, DeviceId, DeviceType};
use crate::prelude::*;
pub struct Urandom;
impl Urandom {
pub fn getrandom(buf: &mut [u8]) -> Result<usize> {
getrandom::getrandom(buf)?;
Ok(buf.len())
}
}
impl Device for Urandom {
fn type_(&self) -> DeviceType {
DeviceType::CharDevice
}
fn id(&self) -> DeviceId {
// The same value as Linux
DeviceId::new(1, 9)
}
fn read(&self, buf: &mut [u8]) -> Result<usize> {
Self::getrandom(buf)
}
fn write(&self, buf: &[u8]) -> Result<usize> {
Ok(buf.len())
}
}

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@ -0,0 +1,36 @@
use crate::device;
use crate::log_syscall_entry;
use crate::prelude::*;
use crate::syscall::SYS_GETRANDOM;
use crate::util::write_bytes_to_user;
use super::SyscallReturn;
pub fn sys_getrandom(buf: Vaddr, count: usize, flags: u32) -> Result<SyscallReturn> {
log_syscall_entry!(SYS_GETRANDOM);
let flags = GetRandomFlags::from_bits_truncate(flags);
debug!(
"buf = 0x{:x}, count = 0x{:x}, flags = {:?}",
buf, count, flags
);
// TODO: support nonblock flag.
// Currently our getrandom implementation relies on x86-specific `rdrand` instruction, so it will never block.
let mut buffer = vec![0u8; count];
let read_len = if flags.contains(GetRandomFlags::GRND_RANDOM) {
device::Random::getrandom(&mut buffer)?
} else {
device::Urandom::getrandom(&mut buffer)?
};
write_bytes_to_user(buf, &buffer)?;
Ok(SyscallReturn::Return(read_len as isize))
}
bitflags::bitflags! {
#[derive(Pod)]
#[repr(C)]
pub struct GetRandomFlags: u32 {
const GRND_NONBLOCK = 0x0001;
const GRND_RANDOM = 0x0002;
const GRND_INSECURE = 0x0004;
}
}

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@ -75,6 +75,7 @@ use self::accept::sys_accept;
use self::bind::sys_bind;
use self::connect::sys_connect;
use self::getpeername::sys_getpeername;
use self::getrandom::sys_getrandom;
use self::getsockname::sys_getsockname;
use self::listen::sys_listen;
use self::pread64::sys_pread64;
@ -114,6 +115,7 @@ mod getpeername;
mod getpgrp;
mod getpid;
mod getppid;
mod getrandom;
mod getsockname;
mod gettid;
mod gettimeofday;
@ -295,7 +297,8 @@ define_syscall_nums!(
SYS_UTIMENSAT = 280,
SYS_EPOLL_CREATE1 = 291,
SYS_PIPE2 = 293,
SYS_PRLIMIT64 = 302
SYS_PRLIMIT64 = 302,
SYS_GETRANDOM = 318
);
pub struct SyscallArgument {
@ -453,6 +456,7 @@ pub fn syscall_dispatch(
SYS_EPOLL_CREATE1 => syscall_handler!(1, sys_epoll_create1, args),
SYS_PIPE2 => syscall_handler!(2, sys_pipe2, args),
SYS_PRLIMIT64 => syscall_handler!(4, sys_prlimit64, args),
SYS_GETRANDOM => syscall_handler!(3, sys_getrandom, args),
_ => {
error!("Unimplemented syscall number: {}", syscall_number);
return_errno_with_message!(Errno::ENOSYS, "Syscall was unimplemented");