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//go:build testsuite
// The sharefs test program checks cli behaviour and exercises the filesystem
// implemented by cmd/sharefs using fs_mark.
package main
import (
"errors"
"log"
"os"
"os/exec"
"strings"
"syscall"
"hakurei.app/test/internal/testsuite"
)
// checkBadOpts invokes cmd/sharefs with the specified options and compares
// the resulting error message.
func checkBadOpts(cred *syscall.Credential, opts, want string) {
var buf strings.Builder
buf.Grow(len(want))
cmd := exec.Command(
"sharefs",
"-f",
"-o", "source=/etc,"+opts,
"/mnt",
)
cmd.SysProcAttr = &syscall.SysProcAttr{
Pdeathsig: syscall.SIGKILL,
Credential: cred,
}
cmd.Stderr = &buf
err := cmd.Run()
if err == nil {
log.Fatalf("opts=%q, unexpected success", opts)
}
if e, ok := errors.AsType[*exec.ExitError](err); !ok {
log.Fatal(err)
} else if !e.Exited() {
log.Fatal(e)
}
if got := buf.String(); got != want {
log.Fatalf("opts=%q\n\t got:%q\n\twant:%q", opts, got, want)
}
}
func main() {
go testsuite.ReceiveSignals()
cred := syscall.Credential{Uid: 1000, Gid: 100}
if err := os.Mkdir("result", 0755); err != nil {
log.Fatal(err)
}
done := make(chan struct{})
go func() {
defer close(done)
testsuite.MustRun(
nil, nil,
"fs_mark",
"-v",
"-d", "/sdcard/fs_mark",
"-l", "result/fs_mark.log",
)
}()
log.Println("checking malformed setuid/setgid representation")
checkBadOpts(&cred, "setuid=ff", "sharefs: invalid value for option setuid\n")
checkBadOpts(&cred, "setgid=ff", "sharefs: invalid value for option setgid\n")
log.Println("checking bounds check for setuid/setgid")
checkBadOpts(&cred, "setuid=0", "sharefs: invalid value for option setuid\n")
checkBadOpts(&cred, "setgid=0", "sharefs: invalid value for option setgid\n")
checkBadOpts(&cred, "setuid=-1", "sharefs: invalid value for option setuid\n")
checkBadOpts(&cred, "setgid=-1", "sharefs: invalid value for option setgid\n")
log.Println("checking non-root setuid/setgid")
checkBadOpts(&cred, "setuid=1023", "sharefs: setuid and setgid has no effect when not starting as root\n")
checkBadOpts(&cred, "setgid=1023", "sharefs: setuid and setgid has no effect when not starting as root\n")
checkBadOpts(&cred, "setuid=1023,setgid=1023", "sharefs: setuid and setgid has no effect when not starting as root\n")
checkBadOpts(&cred, "mkdir", "sharefs: mkdir has no effect when not starting as root\n")
log.Println("checking root without setuid/setgid")
checkBadOpts(nil, "allow_other", "sharefs: setuid and setgid must not be 0\n")
checkBadOpts(nil, "setuid=1023", "sharefs: setuid and setgid must not be 0\n")
checkBadOpts(nil, "setgid=1023", "sharefs: setuid and setgid must not be 0\n")
log.Println("verifying mount point")
if err := os.Remove("/mnt"); err != nil {
log.Fatal(err)
}
log.Println("checking unprivileged mount/unmount")
testsuite.MustRun(&cred, nil, "mkdir", "/tmp/sdcard", "/tmp/persistent")
testsuite.MustRun(&cred, nil, "sharefs", "-o", "source=/tmp/persistent", "/tmp/sdcard")
testsuite.MustRun(&cred, nil, "touch", "/tmp/sdcard/check")
testsuite.MustRun(&cred, nil, "umount", "/tmp/sdcard")
testsuite.MustRun(&cred, nil, "rm", "/tmp/persistent/check")
testsuite.MustRun(&cred, nil, "rmdir", "/tmp/sdcard", "/tmp/persistent")
log.Println("waiting for fs_mark to complete")
<-done
const backingDir = "/var/lib/sdcard"
sharefsCred := syscall.Credential{Uid: 1023, Gid: 1023}
log.Println("checking permissions")
testsuite.MustRun(&sharefsCred, nil, "touch", backingDir+"/fs_mark/.check")
testsuite.MustRun(&sharefsCred, nil, "rm", backingDir+"/fs_mark/.check")
testsuite.MustRun(&cred, nil, "rm", "-rf", "/sdcard/fs_mark")
if _, err := os.ReadDir(backingDir + "/fs_mark"); err == nil {
log.Fatal("fs_mark directory was not removed")
} else if !errors.Is(err, os.ErrNotExist) {
log.Fatal(err)
}
}
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