README
¶
embedexe
Run a program stored in a byte array such as an executable or a directory of executables embedded in a Go binary.
LIMITATIONS
-
the executable must either be statically linked or the linked libraries available on the filesystem
-
only works on Linux (but not on ChromeOS/crostini where the W^X policies disable executing memfds)
-
an embedded executable cannot run another executable embedded in the same binary
-
an embedded executable cannot use a library embedded in the same binary
EXAMPLES
-
embedexe: Using a file descriptor path
-
embedexe/fdexec: Using a file descriptor
-
embedexe/exec: Using a byte array
-
fsexe: embed a directory of executables in a Go binary and run from memory
Run an embedded executable
// Echotest forks and runs an embedded echo(1).
//
// cp /bin/echo .
// go build
// ./echotest hello world
package main
import (
_ "embed"
"log"
"os"
"codeberg.org/msantos/embedexe/exec"
)
//go:embed echo
var echo []byte
func main() {
cmd := exec.Command(echo, os.Args[1:]...)
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
if err := cmd.Run(); err != nil {
log.Fatalln("run:", cmd, err)
}
}
Documentation
¶
Overview ¶
Package embedexe executes a program stored in a byte array such as an executable or a directory of executables embedded in a Go binary.
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type FD ¶
type FD struct {
// contains filtered or unexported fields
}
func Open ¶
Open returns a file descriptor to an executable stored in memory.
Example ¶
package main
import (
"fmt"
"os"
"codeberg.org/msantos/embedexe"
)
func main() {
b := []byte("#!/bin/sh\necho $@")
fd, err := embedexe.Open(b, "example")
if err != nil {
fmt.Println(err)
return
}
defer fd.Close()
if err := fd.Exec([]string{"example", "test"}, os.Environ()); err != nil {
fmt.Println(err)
return
}
}
func (*FD) Exec ¶
Exec runs the executable referenced by the file descriptor, replacing the current running process image.
func (*FD) Path ¶
Path returns the path to the executable file descriptor. Running the executable using the file descriptor path directly is an alternative to running by file descriptor in Exec.
Example ¶
package main
import (
"fmt"
"os"
"os/exec"
"codeberg.org/msantos/embedexe"
)
func main() {
b, err := os.ReadFile("/bin/echo")
if err != nil {
fmt.Println(err)
return
}
fd, err := embedexe.Open(b, "echo")
if err != nil {
fmt.Println(err)
return
}
cmd := exec.Command(fd.Path(), "-n", "test", "abc")
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
if err := cmd.Run(); err != nil {
fmt.Println(err)
return
}
}
Output: test abc
Example (Sh) ¶
An example of running a script contained in a memfd without execute permissions.
package main
import (
"fmt"
"os"
"os/exec"
"codeberg.org/msantos/embedexe"
)
func main() {
b := []byte("#!/bin/sh\necho $@")
fd, err := embedexe.Open(b, "sh")
if err != nil {
fmt.Println(err)
return
}
cmd := exec.Command("/bin/sh", fd.Path(), "-n", "test", "abc")
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
if err := cmd.Run(); err != nil {
fmt.Println(err)
return
}
}
Output: test abc
func (*FD) SetCloseExec ¶
SetCloseExec enables or disables the O_CLOEXEC flag on the file descriptor.
Source Files
Directories
¶
| Path | Synopsis |
|---|---|
|
examples
|
|
|
fileexe
command
Fileexe forks and runs an embedded executable.
|
Fileexe forks and runs an embedded executable. |
|
fsexe
command
Fsexe forks and runs an executable from an embedded directory of executables.
|
Fsexe forks and runs an executable from an embedded directory of executables. |
|
Package exec runs a command stored as bytes in memory.
|
Package exec runs a command stored as bytes in memory. |
|
Package fdexec runs a command by file descriptor.
|
Package fdexec runs a command by file descriptor. |
|
internal
|
|
|
reexec
Package reexec reexecs the process image using a file descriptor.
|
Package reexec reexecs the process image using a file descriptor. |