Initial commit of RR 2.0v2.0.0-alpha1

1 files changed, 56 insertions, 0 deletions

diff --git a/util/isolate.go b/util/isolate.go
new file mode 100644
index 00000000..005c430e
--- /dev/null
+++ b/util/isolate.go
@@ -0,0 +1,56 @@
+// +build !windows
+
+package util
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"os/user"
+	"strconv"
+	"syscall"
+)
+
+// IsolateProcess change gpid for the process to avoid bypassing signals to php processes.
+func IsolateProcess(cmd *exec.Cmd) {
+	cmd.SysProcAttr = &syscall.SysProcAttr{Setpgid: true, Pgid: 0}
+}
+
+// ExecuteFromUser may work only if run RR under root user
+func ExecuteFromUser(cmd *exec.Cmd, u string) error {
+	usr, err := user.Lookup(u)
+	if err != nil {
+		return err
+	}
+
+	usrI32, err := strconv.Atoi(usr.Uid)
+	if err != nil {
+		return err
+	}
+
+	grI32, err := strconv.Atoi(usr.Gid)
+	if err != nil {
+		return err
+	}
+
+	// For more information:
+	// https://www.man7.org/linux/man-pages/man7/user_namespaces.7.html
+	// https://www.man7.org/linux/man-pages/man7/namespaces.7.html
+	if _, err := os.Stat("/proc/self/ns/user"); err != nil {
+		if os.IsNotExist(err) {
+			return fmt.Errorf("kernel doesn't support user namespaces")
+		}
+		if os.IsPermission(err) {
+			return fmt.Errorf("unable to test user namespaces due to permissions")
+		}
+
+		return fmt.Errorf("failed to stat /proc/self/ns/user: %v", err)
+	}
+
+	cmd.SysProcAttr.Credential = &syscall.Credential{
+		Uid: uint32(usrI32),
+		Gid: uint32(grI32),
+	}
+
+	return nil
+}