1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253
use std::cell::Cell;
use rustc_middle::ty::ScalarInt;
use crate::*;
use epoll::{Epoll, EpollEvent};
use event::Event;
use socketpair::SocketPair;
use shims::unix::fs::EvalContextExt as _;
pub mod epoll;
pub mod event;
pub mod socketpair;
impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
/// This function returns a file descriptor referring to the new `Epoll` instance. This file
/// descriptor is used for all subsequent calls to the epoll interface. If the `flags` argument
/// is 0, then this function is the same as `epoll_create()`.
///
/// <https://linux.die.net/man/2/epoll_create1>
fn epoll_create1(
&mut self,
flags: &OpTy<'tcx, Provenance>,
) -> InterpResult<'tcx, Scalar<Provenance>> {
let this = self.eval_context_mut();
let flags = this.read_scalar(flags)?.to_i32()?;
let epoll_cloexec = this.eval_libc_i32("EPOLL_CLOEXEC");
if flags == epoll_cloexec {
// Miri does not support exec, so this flag has no effect.
} else if flags != 0 {
throw_unsup_format!("epoll_create1 flags {flags} are not implemented");
}
let fd = this.machine.file_handler.insert_fd(Box::new(Epoll::default()));
Ok(Scalar::from_i32(fd))
}
/// This function performs control operations on the `Epoll` instance referred to by the file
/// descriptor `epfd`. It requests that the operation `op` be performed for the target file
/// descriptor, `fd`.
///
/// Valid values for the op argument are:
/// `EPOLL_CTL_ADD` - Register the target file descriptor `fd` on the `Epoll` instance referred
/// to by the file descriptor `epfd` and associate the event `event` with the internal file
/// linked to `fd`.
/// `EPOLL_CTL_MOD` - Change the event `event` associated with the target file descriptor `fd`.
/// `EPOLL_CTL_DEL` - Deregister the target file descriptor `fd` from the `Epoll` instance
/// referred to by `epfd`. The `event` is ignored and can be null.
///
/// <https://linux.die.net/man/2/epoll_ctl>
fn epoll_ctl(
&mut self,
epfd: &OpTy<'tcx, Provenance>,
op: &OpTy<'tcx, Provenance>,
fd: &OpTy<'tcx, Provenance>,
event: &OpTy<'tcx, Provenance>,
) -> InterpResult<'tcx, Scalar<Provenance>> {
let this = self.eval_context_mut();
let epfd = this.read_scalar(epfd)?.to_i32()?;
let op = this.read_scalar(op)?.to_i32()?;
let fd = this.read_scalar(fd)?.to_i32()?;
let _event = this.read_scalar(event)?.to_pointer(this)?;
let epoll_ctl_add = this.eval_libc_i32("EPOLL_CTL_ADD");
let epoll_ctl_mod = this.eval_libc_i32("EPOLL_CTL_MOD");
let epoll_ctl_del = this.eval_libc_i32("EPOLL_CTL_DEL");
if op == epoll_ctl_add || op == epoll_ctl_mod {
let event = this.deref_pointer_as(event, this.libc_ty_layout("epoll_event"))?;
let events = this.project_field(&event, 0)?;
let events = this.read_scalar(&events)?.to_u32()?;
let data = this.project_field(&event, 1)?;
let data = this.read_scalar(&data)?;
let event = EpollEvent { events, data };
if let Some(epfd) = this.machine.file_handler.handles.get_mut(&epfd) {
let epfd = epfd
.downcast_mut::<Epoll>()
.ok_or_else(|| err_unsup_format!("non-epoll FD passed to `epoll_ctl`"))?;
epfd.file_descriptors.insert(fd, event);
Ok(Scalar::from_i32(0))
} else {
Ok(Scalar::from_i32(this.handle_not_found()?))
}
} else if op == epoll_ctl_del {
if let Some(epfd) = this.machine.file_handler.handles.get_mut(&epfd) {
let epfd = epfd
.downcast_mut::<Epoll>()
.ok_or_else(|| err_unsup_format!("non-epoll FD passed to `epoll_ctl`"))?;
epfd.file_descriptors.remove(&fd);
Ok(Scalar::from_i32(0))
} else {
Ok(Scalar::from_i32(this.handle_not_found()?))
}
} else {
let einval = this.eval_libc("EINVAL");
this.set_last_error(einval)?;
Ok(Scalar::from_i32(-1))
}
}
/// The `epoll_wait()` system call waits for events on the `Epoll`
/// instance referred to by the file descriptor `epfd`. The buffer
/// pointed to by `events` is used to return information from the ready
/// list about file descriptors in the interest list that have some
/// events available. Up to `maxevents` are returned by `epoll_wait()`.
/// The `maxevents` argument must be greater than zero.
/// The `timeout` argument specifies the number of milliseconds that
/// `epoll_wait()` will block. Time is measured against the
/// CLOCK_MONOTONIC clock.
/// A call to `epoll_wait()` will block until either:
/// • a file descriptor delivers an event;
/// • the call is interrupted by a signal handler; or
/// • the timeout expires.
/// Note that the timeout interval will be rounded up to the system
/// clock granularity, and kernel scheduling delays mean that the
/// blocking interval may overrun by a small amount. Specifying a
/// timeout of -1 causes `epoll_wait()` to block indefinitely, while
/// specifying a timeout equal to zero cause `epoll_wait()` to return
/// immediately, even if no events are available.
///
/// On success, `epoll_wait()` returns the number of file descriptors
/// ready for the requested I/O, or zero if no file descriptor became
/// ready during the requested timeout milliseconds. On failure,
/// `epoll_wait()` returns -1 and errno is set to indicate the error.
///
/// <https://man7.org/linux/man-pages/man2/epoll_wait.2.html>
fn epoll_wait(
&mut self,
epfd: &OpTy<'tcx, Provenance>,
events: &OpTy<'tcx, Provenance>,
maxevents: &OpTy<'tcx, Provenance>,
timeout: &OpTy<'tcx, Provenance>,
) -> InterpResult<'tcx, Scalar<Provenance>> {
let this = self.eval_context_mut();
let epfd = this.read_scalar(epfd)?.to_i32()?;
let _events = this.read_scalar(events)?.to_pointer(this)?;
let _maxevents = this.read_scalar(maxevents)?.to_i32()?;
let _timeout = this.read_scalar(timeout)?.to_i32()?;
if let Some(epfd) = this.machine.file_handler.handles.get_mut(&epfd) {
let _epfd = epfd
.downcast_mut::<Epoll>()
.ok_or_else(|| err_unsup_format!("non-epoll FD passed to `epoll_wait`"))?;
// FIXME return number of events ready when scheme for marking events ready exists
throw_unsup_format!("returning ready events from epoll_wait is not yet implemented");
} else {
Ok(Scalar::from_i32(this.handle_not_found()?))
}
}
/// This function creates an `Event` that is used as an event wait/notify mechanism by
/// user-space applications, and by the kernel to notify user-space applications of events.
/// The `Event` contains an `u64` counter maintained by the kernel. The counter is initialized
/// with the value specified in the `initval` argument.
///
/// A new file descriptor referring to the `Event` is returned. The `read`, `write`, `poll`,
/// `select`, and `close` operations can be performed on the file descriptor. For more
/// information on these operations, see the man page linked below.
///
/// The `flags` are not currently implemented for eventfd.
/// The `flags` may be bitwise ORed to change the behavior of `eventfd`:
/// `EFD_CLOEXEC` - Set the close-on-exec (`FD_CLOEXEC`) flag on the new file descriptor.
/// `EFD_NONBLOCK` - Set the `O_NONBLOCK` file status flag on the new open file description.
/// `EFD_SEMAPHORE` - miri does not support semaphore-like semantics.
///
/// <https://linux.die.net/man/2/eventfd>
#[expect(clippy::needless_if)]
fn eventfd(
&mut self,
val: &OpTy<'tcx, Provenance>,
flags: &OpTy<'tcx, Provenance>,
) -> InterpResult<'tcx, Scalar<Provenance>> {
let this = self.eval_context_mut();
let val = this.read_scalar(val)?.to_u32()?;
let flags = this.read_scalar(flags)?.to_i32()?;
let efd_cloexec = this.eval_libc_i32("EFD_CLOEXEC");
let efd_nonblock = this.eval_libc_i32("EFD_NONBLOCK");
let efd_semaphore = this.eval_libc_i32("EFD_SEMAPHORE");
if flags & (efd_cloexec | efd_nonblock | efd_semaphore) == 0 {
throw_unsup_format!("{flags} is unsupported");
}
// FIXME handle the cloexec and nonblock flags
if flags & efd_cloexec == efd_cloexec {}
if flags & efd_nonblock == efd_nonblock {}
if flags & efd_semaphore == efd_semaphore {
throw_unsup_format!("EFD_SEMAPHORE is unsupported");
}
let fh = &mut this.machine.file_handler;
let fd = fh.insert_fd(Box::new(Event { val: Cell::new(val.into()) }));
Ok(Scalar::from_i32(fd))
}
/// Currently this function creates new `SocketPair`s without specifying the domain, type, or
/// protocol of the new socket and these are stored in the socket values `sv` argument.
///
/// This function creates an unnamed pair of connected sockets in the specified domain, of the
/// specified type, and using the optionally specified protocol.
///
/// The `domain` argument specified a communication domain; this selects the protocol family
/// used for communication. The socket `type` specifies the communication semantics.
/// The `protocol` specifies a particular protocol to use with the socket. Normally there's
/// only a single protocol supported for a particular socket type within a given protocol
/// family, in which case `protocol` can be specified as 0. It is possible that many protocols
/// exist and in that case, a particular protocol must be specified.
///
/// For more information on the arguments see the socket manpage:
/// <https://linux.die.net/man/2/socket>
///
/// <https://linux.die.net/man/2/socketpair>
fn socketpair(
&mut self,
domain: &OpTy<'tcx, Provenance>,
type_: &OpTy<'tcx, Provenance>,
protocol: &OpTy<'tcx, Provenance>,
sv: &OpTy<'tcx, Provenance>,
) -> InterpResult<'tcx, Scalar<Provenance>> {
let this = self.eval_context_mut();
let _domain = this.read_scalar(domain)?.to_i32()?;
let _type_ = this.read_scalar(type_)?.to_i32()?;
let _protocol = this.read_scalar(protocol)?.to_i32()?;
let sv = this.deref_pointer(sv)?;
let fh = &mut this.machine.file_handler;
let sv0 = fh.insert_fd(Box::new(SocketPair));
let sv0 = ScalarInt::try_from_int(sv0, sv.layout.size).unwrap();
let sv1 = fh.insert_fd(Box::new(SocketPair));
let sv1 = ScalarInt::try_from_int(sv1, sv.layout.size).unwrap();
this.write_scalar(sv0, &sv)?;
this.write_scalar(sv1, &sv.offset(sv.layout.size, sv.layout, this)?)?;
Ok(Scalar::from_i32(0))
}
}