Add the redirection of standard I/O for process

demos/embedded_mode/bench_driver/main.c

@@ -65,7 +65,7 @@ int main(int argc, char* argv[]) {
 
     // Use Occlum PAL to execute the cmd
     int exit_status = 0;
-    if (occlum_pal_exec(cmd_path, cmd_args, &exit_status) < 0) {
+    if (occlum_pal_exec(cmd_path, cmd_args, NULL, &exit_status) < 0) {
         return EXIT_FAILURE;
     }
 

src/Enclave.edl

@@ -27,7 +27,8 @@ enclave {
          */
         public int occlum_ecall_new_process(
             [in, string] const char* executable_path,
-            [user_check] const char** argv);
+            [user_check] const char** argv,
+            [in] const struct occlum_stdio_fds* io_fds);
 
         /*
          * Execute the LibOS thread specified by the TID.

src/libos/include/edl/occlum_edl_types.h

@@ -10,4 +10,10 @@ struct timeval {
     suseconds_t tv_usec;    /* microseconds */
 };
 
+struct occlum_stdio_fds {
+    int stdin_fd;
+    int stdout_fd;
+    int stderr_fd;
+};
+
 #endif /* __OCCLUM_EDL_TYPES_H__ */

src/libos/src/entry.rs

@@ -1,5 +1,6 @@
 use super::*;
 use exception::*;
+use fs::HostStdioFds;
 use process::pid_t;
 use std::ffi::{CStr, CString, OsString};
 use std::path::{Path, PathBuf};
@@ -56,13 +57,14 @@ pub extern "C" fn occlum_ecall_init(log_level: *const c_char) -> i32 {
 pub extern "C" fn occlum_ecall_new_process(
     path_buf: *const c_char,
     argv: *const *const c_char,
+    host_stdio_fds: *const HostStdioFds,
 ) -> i32 {
     if HAS_INIT.load(Ordering::SeqCst) == false {
         return EXIT_STATUS_INTERNAL_ERROR;
     }
 
-    let (path, args) = match parse_arguments(path_buf, argv) {
+    let (path, args, host_stdio_fds) = match parse_arguments(path_buf, argv, host_stdio_fds) {
-        Ok(path_and_args) => path_and_args,
+        Ok(path_and_args_and_host_stdio_fds) => path_and_args_and_host_stdio_fds,
         Err(e) => {
             eprintln!("invalid arguments for LibOS: {}", e.backtrace());
             return EXIT_STATUS_INTERNAL_ERROR;
@@ -70,11 +72,13 @@ pub extern "C" fn occlum_ecall_new_process(
     };
     let _ = backtrace::enable_backtrace(ENCLAVE_PATH, PrintFormat::Short);
     panic::catch_unwind(|| {
-        backtrace::__rust_begin_short_backtrace(|| match do_new_process(&path, &args) {
+        backtrace::__rust_begin_short_backtrace(|| {
-            Ok(pid_t) => pid_t as i32,
+            match do_new_process(&path, &args, &host_stdio_fds) {
-            Err(e) => {
+                Ok(pid_t) => pid_t as i32,
-                eprintln!("failed to boot up LibOS: {}", e.backtrace());
+                Err(e) => {
-                EXIT_STATUS_INTERNAL_ERROR
+                    eprintln!("failed to boot up LibOS: {}", e.backtrace());
+                    EXIT_STATUS_INTERNAL_ERROR
+                }
             }
         })
     })
@@ -135,7 +139,8 @@ fn parse_log_level(level_chars: *const c_char) -> Result<LevelFilter> {
 fn parse_arguments(
     path_ptr: *const c_char,
     argv: *const *const c_char,
-) -> Result<(PathBuf, Vec<CString>)> {
+    host_stdio_fds: *const HostStdioFds,
+) -> Result<(PathBuf, Vec<CString>, HostStdioFds)> {
     let path_buf = {
         let path_cstring = clone_cstring_safely(path_ptr)?;
         let path_string = path_cstring
@@ -155,18 +160,31 @@ fn parse_arguments(
 
     let mut args = clone_cstrings_safely(argv)?;
     args.insert(0, program_cstring);
-    Ok((path_buf, args))
+
+    let host_stdio_fds = HostStdioFds::from_user(host_stdio_fds)?;
+
+    Ok((path_buf, args, host_stdio_fds))
 }
 
-fn do_new_process(program_path: &PathBuf, argv: &Vec<CString>) -> Result<pid_t> {
+fn do_new_process(
+    program_path: &PathBuf,
+    argv: &Vec<CString>,
+    host_stdio_fds: &HostStdioFds,
+) -> Result<pid_t> {
     validate_program_path(program_path)?;
 
     let envp = &config::LIBOS_CONFIG.env;
     let file_actions = Vec::new();
     let parent = &process::IDLE_PROCESS;
     let program_path_str = program_path.to_str().unwrap();
-    let new_tid =
+    let new_tid = process::do_spawn_without_exec(
-        process::do_spawn_without_exec(&program_path_str, argv, envp, &file_actions, parent)?;
+        &program_path_str,
+        argv,
+        envp,
+        &file_actions,
+        host_stdio_fds,
+        parent,
+    )?;
     Ok(new_tid)
 }
 

src/libos/src/fs/mod.rs

@@ -19,7 +19,7 @@ pub use self::file_table::{FileDesc, FileTable};
 pub use self::inode_file::{AsINodeFile, INodeExt, INodeFile};
 pub use self::pipe::Pipe;
 pub use self::rootfs::ROOT_INODE;
-pub use self::stdio::{StdinFile, StdoutFile};
+pub use self::stdio::{HostStdioFds, StdinFile, StdoutFile};
 pub use self::syscalls::*;
 
 mod dev_fs;

src/libos/src/fs/stdio.rs

@@ -1,20 +1,114 @@
 use super::*;
+use core::cell::RefCell;
+use core::cmp;
+use std::io::{BufReader, LineWriter};
+use std::sync::SgxMutex;
+
+macro_rules! try_libc_stdio {
+    ($ret: expr) => {{
+        let ret = unsafe { $ret };
+        if ret < 0 {
+            let errno_c = unsafe { libc::errno() };
+            Err(errno!(Errno::from(errno_c as u32)))
+        } else {
+            Ok(ret)
+        }
+    }};
+}
+
+// Struct for the occlum_stdio_fds
+#[repr(C)]
+pub struct HostStdioFds {
+    pub stdin_fd: i32,
+    pub stdout_fd: i32,
+    pub stderr_fd: i32,
+}
+
+impl HostStdioFds {
+    pub fn from_user(ptr: *const HostStdioFds) -> Result<Self> {
+        if ptr.is_null() {
+            return Ok(Self {
+                stdin_fd: libc::STDIN_FILENO,
+                stdout_fd: libc::STDOUT_FILENO,
+                stderr_fd: libc::STDERR_FILENO,
+            });
+        }
+        let host_stdio_fds_c = unsafe { &*ptr };
+        if host_stdio_fds_c.stdin_fd < 0
+            || host_stdio_fds_c.stdout_fd < 0
+            || host_stdio_fds_c.stderr_fd < 0
+        {
+            return_errno!(EBADF, "invalid file descriptor");
+        }
+        Ok(Self {
+            stdin_fd: host_stdio_fds_c.stdin_fd,
+            stdout_fd: host_stdio_fds_c.stdout_fd,
+            stderr_fd: host_stdio_fds_c.stderr_fd,
+        })
+    }
+}
+
+struct StdoutRaw {
+    host_fd: i32,
+}
+
+impl StdoutRaw {
+    pub fn new(host_fd: FileDesc) -> Self {
+        Self {
+            host_fd: host_fd as i32,
+        }
+    }
+}
+
+impl std::io::Write for StdoutRaw {
+    fn write(&mut self, buf: &[u8]) -> std::io::Result<usize> {
+        let writting_len = cmp::min(buf.len(), size_t::max_value() as usize);
+        let ret = try_libc_stdio!(libc::ocall::write(
+            self.host_fd,
+            buf.as_ptr() as *const c_void,
+            writting_len,
+        ))
+        .unwrap_or_else(|err| {
+            warn!("tolerate the write error: {:?}", err.errno());
+            writting_len as isize
+        });
+        // sanity check
+        assert!(ret <= writting_len as isize);
+        Ok(ret as usize)
+    }
+
+    fn flush(&mut self) -> std::io::Result<()> {
+        Ok(())
+    }
+}
 
 pub struct StdoutFile {
-    inner: std::io::Stdout,
+    inner: SgxMutex<LineWriter<StdoutRaw>>,
+    host_fd: FileDesc,
 }
 
 impl StdoutFile {
-    pub fn new() -> StdoutFile {
+    pub fn new(host_fd: FileDesc) -> Self {
         StdoutFile {
-            inner: std::io::stdout(),
+            inner: SgxMutex::new(LineWriter::new(StdoutRaw::new(host_fd))),
+            host_fd,
         }
     }
+
+    fn get_host_fd(&self) -> FileDesc {
+        self.host_fd
+    }
 }
 
 impl File for StdoutFile {
     fn write(&self, buf: &[u8]) -> Result<usize> {
-        let write_len = { self.inner.lock().write(buf).map_err(|e| errno!(e))? };
+        let write_len = {
+            self.inner
+                .lock()
+                .unwrap()
+                .write(buf)
+                .map_err(|e| errno!(e))?
+        };
         Ok(write_len)
     }
 
@@ -23,7 +117,7 @@ impl File for StdoutFile {
     }
 
     fn writev(&self, bufs: &[&[u8]]) -> Result<usize> {
-        let mut guard = self.inner.lock();
+        let mut guard = self.inner.lock().unwrap();
         let mut total_bytes = 0;
         for buf in bufs {
             match guard.write(buf) {
@@ -70,7 +164,7 @@ impl File for StdoutFile {
     }
 
     fn sync_data(&self) -> Result<()> {
-        self.inner.lock().flush()?;
+        self.inner.lock().unwrap().flush()?;
         Ok(())
     }
 
@@ -86,10 +180,7 @@ impl File for StdoutFile {
 
         let cmd_bits = cmd.cmd_num() as c_int;
         let cmd_arg_ptr = cmd.arg_ptr() as *const c_int;
-        let host_stdout_fd = {
+        let host_stdout_fd = self.get_host_fd() as i32;
-            use std::os::unix::io::AsRawFd;
-            self.inner.as_raw_fd() as i32
-        };
         try_libc!(libc::ocall::ioctl_arg1(
             host_stdout_fd,
             cmd_bits,
@@ -107,33 +198,75 @@ impl File for StdoutFile {
 
 impl Debug for StdoutFile {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        write!(f, "StdoutFile")
+        write!(f, "StdoutFile with host_fd: {}", self.host_fd)
     }
 }
 
 unsafe impl Send for StdoutFile {}
 unsafe impl Sync for StdoutFile {}
 
+struct StdinRaw {
+    host_fd: i32,
+}
+
+impl StdinRaw {
+    pub fn new(host_fd: FileDesc) -> Self {
+        Self {
+            host_fd: host_fd as i32,
+        }
+    }
+}
+
+impl std::io::Read for StdinRaw {
+    fn read(&mut self, buf: &mut [u8]) -> std::io::Result<usize> {
+        let reading_len = cmp::min(buf.len(), size_t::max_value() as usize);
+        let ret = try_libc_stdio!(libc::ocall::read(
+            self.host_fd,
+            buf.as_mut_ptr() as *mut c_void,
+            reading_len,
+        ))
+        .unwrap_or_else(|err| {
+            warn!("tolerate the read error: {:?}", err.errno());
+            0
+        });
+        // sanity check
+        assert!(ret <= reading_len as isize);
+        Ok(ret as usize)
+    }
+}
+
 pub struct StdinFile {
-    inner: std::io::Stdin,
+    inner: SgxMutex<BufReader<StdinRaw>>,
+    host_fd: FileDesc,
 }
 
 impl StdinFile {
-    pub fn new() -> StdinFile {
+    pub fn new(host_fd: FileDesc) -> Self {
         StdinFile {
-            inner: std::io::stdin(),
+            inner: SgxMutex::new(BufReader::new(StdinRaw::new(host_fd))),
+            host_fd,
         }
     }
+
+    fn get_host_fd(&self) -> FileDesc {
+        self.host_fd
+    }
 }
 
 impl File for StdinFile {
     fn read(&self, buf: &mut [u8]) -> Result<usize> {
-        let read_len = { self.inner.lock().read(buf).map_err(|e| errno!(e))? };
+        let read_len = {
+            self.inner
+                .lock()
+                .unwrap()
+                .read(buf)
+                .map_err(|e| errno!(e))?
+        };
         Ok(read_len)
     }
 
     fn readv(&self, bufs: &mut [&mut [u8]]) -> Result<usize> {
-        let mut guard = self.inner.lock();
+        let mut guard = self.inner.lock().unwrap();
         let mut total_bytes = 0;
         for buf in bufs {
             match guard.read(buf) {
@@ -175,6 +308,29 @@ impl File for StdinFile {
         })
     }
 
+    fn ioctl(&self, cmd: &mut IoctlCmd) -> Result<()> {
+        let can_delegate_to_host = match cmd {
+            IoctlCmd::TIOCGWINSZ(_) => true,
+            IoctlCmd::TIOCSWINSZ(_) => true,
+            _ => false,
+        };
+        if !can_delegate_to_host {
+            return_errno!(EINVAL, "unknown ioctl cmd for stdin");
+        }
+
+        let cmd_bits = cmd.cmd_num() as c_int;
+        let cmd_arg_ptr = cmd.arg_ptr() as *const c_int;
+        let host_stdin_fd = self.get_host_fd() as i32;
+        try_libc!(libc::ocall::ioctl_arg1(
+            host_stdin_fd,
+            cmd_bits,
+            cmd_arg_ptr
+        ));
+        cmd.validate_arg_val()?;
+
+        Ok(())
+    }
+
     fn as_any(&self) -> &dyn Any {
         self
     }
@@ -182,7 +338,7 @@ impl File for StdinFile {
 
 impl Debug for StdinFile {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        write!(f, "StdinFile")
+        write!(f, "StdinFile with host_fd: {}", self.host_fd)
     }
 }
 

src/libos/src/process/spawn/mod.rs

@@ -5,7 +5,8 @@ use std::path::Path;
 use std::sgxfs::SgxFile;
 
 use super::fs::{
-    CreationFlags, File, FileDesc, FileTable, INodeExt, StdinFile, StdoutFile, ROOT_INODE,
+    CreationFlags, File, FileDesc, FileTable, HostStdioFds, INodeExt, StdinFile, StdoutFile,
+    ROOT_INODE,
 };
 use super::misc::ResourceLimitsRef;
 use super::vm::{ProcessVM, ProcessVMBuilder};
@@ -24,7 +25,8 @@ pub fn do_spawn(
     file_actions: &[FileAction],
     parent_ref: &ProcessRef,
 ) -> Result<pid_t> {
-    let (new_tid, new_process_ref) = new_process(elf_path, argv, envp, file_actions, parent_ref)?;
+    let (new_tid, new_process_ref) =
+        new_process(elf_path, argv, envp, file_actions, None, parent_ref)?;
     task::enqueue_and_exec_task(new_tid, new_process_ref);
     Ok(new_tid)
 }
@@ -34,9 +36,17 @@ pub fn do_spawn_without_exec(
     argv: &[CString],
     envp: &[CString],
     file_actions: &[FileAction],
+    host_stdio_fds: &HostStdioFds,
     parent_ref: &ProcessRef,
 ) -> Result<pid_t> {
-    let (new_tid, new_process_ref) = new_process(elf_path, argv, envp, file_actions, parent_ref)?;
+    let (new_tid, new_process_ref) = new_process(
+        elf_path,
+        argv,
+        envp,
+        file_actions,
+        Some(host_stdio_fds),
+        parent_ref,
+    )?;
     task::enqueue_task(new_tid, new_process_ref);
     Ok(new_tid)
 }
@@ -46,6 +56,7 @@ fn new_process(
     argv: &[CString],
     envp: &[CString],
     file_actions: &[FileAction],
+    host_stdio_fds: Option<&HostStdioFds>,
     parent_ref: &ProcessRef,
 ) -> Result<(pid_t, ProcessRef)> {
     let elf_buf = load_elf_to_vec(elf_path, parent_ref)
@@ -107,7 +118,7 @@ fn new_process(
         };
         let vm_ref = Arc::new(SgxMutex::new(vm));
         let files_ref = {
-            let files = init_files(parent_ref, file_actions)?;
+            let files = init_files(parent_ref, file_actions, host_stdio_fds)?;
             Arc::new(SgxMutex::new(files))
         };
         let rlimits_ref = Default::default();
@@ -145,7 +156,11 @@ fn load_elf_to_vec(elf_path: &str, parent_ref: &ProcessRef) -> Result<Vec<u8>> {
             .map_err(|e| errno!(e.errno(), "failed to read the executable ELF"))
 }
 
-fn init_files(parent_ref: &ProcessRef, file_actions: &[FileAction]) -> Result<FileTable> {
+fn init_files(
+    parent_ref: &ProcessRef,
+    file_actions: &[FileAction],
+    host_stdio_fds: Option<&HostStdioFds>,
+) -> Result<FileTable> {
     // Usually, we just inherit the file table from the parent
     let parent = parent_ref.lock().unwrap();
     let should_inherit_file_table = parent.get_pid() > 0;
@@ -186,10 +201,16 @@ fn init_files(parent_ref: &ProcessRef, file_actions: &[FileAction]) -> Result<Fi
 
     // But, for init process, we initialize file table for it
     let mut file_table = FileTable::new();
-    let stdin: Arc<Box<dyn File>> = Arc::new(Box::new(StdinFile::new()));
+    let stdin: Arc<Box<dyn File>> = Arc::new(Box::new(StdinFile::new(
-    let stdout: Arc<Box<dyn File>> = Arc::new(Box::new(StdoutFile::new()));
+        host_stdio_fds.unwrap().stdin_fd as FileDesc,
-    // TODO: implement and use a real stderr
+    )));
-    let stderr = stdout.clone();
+    let stdout: Arc<Box<dyn File>> = Arc::new(Box::new(StdoutFile::new(
+        host_stdio_fds.unwrap().stdout_fd as FileDesc,
+    )));
+    let stderr: Arc<Box<dyn File>> = Arc::new(Box::new(StdoutFile::new(
+        host_stdio_fds.unwrap().stderr_fd as FileDesc,
+    )));
+
     file_table.put(stdin, false);
     file_table.put(stdout, false);
     file_table.put(stderr, false);

src/libos/src/syscall/mod.rs

@@ -12,7 +12,8 @@ use fs::{
     do_fcntl, do_fdatasync, do_fstat, do_fstatat, do_fsync, do_ftruncate, do_getdents64, do_ioctl,
     do_link, do_lseek, do_lstat, do_mkdir, do_open, do_openat, do_pipe, do_pipe2, do_pread,
     do_pwrite, do_read, do_readlink, do_readv, do_rename, do_rmdir, do_sendfile, do_stat, do_sync,
-    do_truncate, do_unlink, do_write, do_writev, iovec_t, File, FileDesc, FileRef, Stat,
+    do_truncate, do_unlink, do_write, do_writev, iovec_t, File, FileDesc, FileRef, HostStdioFds,
+    Stat,
 };
 use misc::{resource_t, rlimit_t, utsname_t};
 use net::{

src/pal/include/edl/occlum_edl_types.h

@@ -4,5 +4,6 @@
 #include <time.h>               // import struct timespec
 #include <sys/time.h>           // import struct timeval
 #include <sys/uio.h>            // import struct iovec
+#include <occlum_pal_api.h>     // import occlum_stdio_fds
 
 #endif /* __OCCLUM_EDL_TYPES__ */

src/pal/include/occlum_pal_api.h

@@ -33,6 +33,15 @@ typedef struct {
     .log_level = NULL                     \
 }
 
+/*
+ * The struct which consists of file descriptors of standard I/O
+ */
+struct occlum_stdio_fds {
+    int stdin_fd;
+    int stdout_fd;
+    int stderr_fd;
+};
+
 /*
  * @brief Initialize an Occlum enclave
  *
@@ -48,13 +57,19 @@ int occlum_pal_init(occlum_pal_attr_t* attr);
  * @param cmd_path      The path of the command to be executed
  * @param cmd_args      The arguments to the command. The array must be NULL
  *                      terminated.
+ * @param io_fds        The file descriptors of the redirected standard I/O
+ *                      (i.e., stdin, stdout, stderr), If set to NULL, will
+ *                      use the original standard I/O file descriptors.
  * @param exit_status   Output. The exit status of the command. Note that the
  *                      exit status is returned if and only if the function
  *                      succeeds.
  *
  * @retval If 0, then success; otherwise, check errno for the exact error type.
  */
-int occlum_pal_exec(const char* cmd_path, const char** cmd_args, int* exit_status);
+int occlum_pal_exec(const char* cmd_path,
+                    const char** cmd_args,
+                    const struct occlum_stdio_fds* io_fds,
+                    int* exit_status);
 
 /*
  * @brief Destroy teh Occlum enclave

src/pal/src/pal_api.c

@@ -47,7 +47,10 @@ int occlum_pal_init(occlum_pal_attr_t* attr) {
     return 0;
 }
 
-int occlum_pal_exec(const char* cmd_path, const char** cmd_args, int* exit_status) {
+int occlum_pal_exec(const char* cmd_path,
+                    const char** cmd_args,
+                    const struct occlum_stdio_fds* io_fds,
+                    int* exit_status) {
     errno = 0;
 
     if (cmd_path == NULL || cmd_args == NULL || exit_status == NULL) {
@@ -63,7 +66,7 @@ int occlum_pal_exec(const char* cmd_path, const char** cmd_args, int* exit_statu
     }
 
     int libos_tid = -1;
-    sgx_status_t ecall_status = occlum_ecall_new_process(eid, &libos_tid, cmd_path, cmd_args);
+    sgx_status_t ecall_status = occlum_ecall_new_process(eid, &libos_tid, cmd_path, cmd_args, io_fds);
     if (ecall_status != SGX_SUCCESS) {
         const char* sgx_err = pal_get_sgx_error_msg(ecall_status);
         PAL_ERROR("Failed to do ECall: %s", sgx_err);

src/run/main.c

@@ -1,6 +1,7 @@
 #include <linux/limits.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <unistd.h>
 #include <occlum_pal_api.h>
 
 static const char* get_instance_dir(void) {
@@ -32,8 +33,13 @@ int main(int argc, char* argv[]) {
     }
 
     // Use Occlum PAL to execute the cmd
+    struct occlum_stdio_fds io_fds = {
+        .stdin_fd = STDIN_FILENO,
+        .stdout_fd = STDOUT_FILENO,
+        .stderr_fd = STDERR_FILENO,
+    };
     int exit_status = 0;
-    if (occlum_pal_exec(cmd_path, cmd_args, &exit_status) < 0) {
+    if (occlum_pal_exec(cmd_path, cmd_args, &io_fds, &exit_status) < 0) {
         return EXIT_FAILURE;
     }