"ruderich.org/simon/safcm/remote"
)
-func (c *Conn) DialSSH(remote string) error {
+type SSHConfig struct {
+ Host string
+ User string // optional
+ SshConfig string // optional
+}
+
+func (c *Conn) DialSSH(cfg SSHConfig) error {
if c.events == nil {
return fmt.Errorf("cannot reuse Conn")
}
+ remote := cfg.Host
+ if cfg.User != "" {
+ remote = cfg.User + "@" + cfg.Host
+ }
c.debugf("DialSSH: connecting to %q", remote)
opts := "-eu"
// Help debugging by showing executed shell commands
opts += "x"
}
- c.cmd = exec.Command("ssh", remote, "/bin/sh", opts)
- c.remote = remote
+
+ c.sshRemote = remote
+ if cfg.SshConfig != "" {
+ c.sshOpts = []string{"-F", cfg.SshConfig}
+ }
+ c.cmd = exec.Command("ssh",
+ append(append([]string{}, c.sshOpts...),
+ c.sshRemote, "/bin/sh", opts)...)
stdin, err := c.cmd.StdinPipe()
if err != nil {
path := fmt.Sprintf("/tmp/safcm-remote-%d", uid)
c.debugf("DialSSH: probing remote at %q", path)
+
+ // Compatibility for different operating systems
+ var compat string
+ switch goos {
+ case "linux":
+ compat = `
+dir_stat='drwxrwxrwt 0 0'
+file_stat="-rwx------ $(id -u) $(id -g)"
+compat_stat() {
+ stat -c '%A %u %g' "$1"
+}
+compat_sha512sum() {
+ sha512sum "$1"
+}
+`
+ case "freebsd", "openbsd":
+ compat = `
+dir_stat='41777 0 0'
+file_stat="100700 $(id -u) $(id -g)"
+compat_stat() {
+ stat -f '%p %u %g' "$1"
+}
+compat_sha512sum() {
+ sha512 -q "$1"
+}
+`
+ default:
+ return fmt.Errorf("internal error: no support for %q", goos)
+ }
+
// Use a function so the shell cannot execute the input line-wise.
// This is important because we're also using stdin to send data to
// the script. If the shell executes the input line-wise then our
//
// The target directory must no permit other users to delete our files
// or symlink attacks and arbitrary code execution is possible. For
- // /tmp this is guaranteed by the sticky bit. Make sure it has the
- // proper permissions.
+ // /tmp this is guaranteed by the sticky bit. The code verifies the
+ // directory has the proper permissions.
//
// We cannot use `test -f && test -O` because this is open to TOCTOU
// attacks. `stat` gives use the full file state. If the file is owned
- // by us and not a symlink then it's safe to use (assuming sticky or
- // directory not writable by others).
+ // by us and not a symlink then it's safe to use (assuming sticky
+ // directory or directory not writable by others).
//
// `test -e` is only used to prevent error messages if the file
// doesn't exist. It does not guard against any races.
_, err = fmt.Fprintf(stdin, `
+%s
f() {
x=%q
dir="$(dirname "$x")"
- if ! test "$(stat -c '%%A %%u %%g' "$dir")" = 'drwxrwxrwt 0 0'; then
+ if ! test "$(compat_stat "$dir")" = "$dir_stat"; then
echo "unsafe permissions on $dir, aborting" >&2
exit 1
fi
- if test -e "$x" && test "$(stat -c '%%A %%u' "$x")" = "-rwx------ $(id -u)"; then
+ if test -e "$x" && test "$(compat_stat "$x")" = "$file_stat"; then
# Report checksum
- sha512sum "$x"
+ compat_sha512sum "$x"
else
# Empty checksum to request upload
echo
tmp="$(mktemp "$x.XXXXXX")"
# Report filename for upload
echo "$tmp"
-
# Wait for upload to complete
read unused
rm "$tmp"
# Make file executable
chmod 0700 "$x"
+ # Some BSD create files with group wheel in /tmp
+ chgrp "$(id -g)" "$x"
fi
- exec "$x"
+ exec "$x" sync
}
f
-`, path)
+`, compat, path)
if err != nil {
return err
}
path = strings.TrimSuffix(path, "\n")
c.debugf("DialSSH: uploading new remote to %q at %q",
- c.remote, path)
+ c.sshRemote, path)
- cmd := exec.Command("ssh", c.remote,
- fmt.Sprintf("cat > %q", path))
+ cmd := exec.Command("ssh",
+ append(append([]string{}, c.sshOpts...),
+ c.sshRemote,
+ fmt.Sprintf("cat > %q", path))...)
cmd.Stdin = bytes.NewReader(helper)
- err = c.handleStderrAsEvents(cmd)
+ err = c.handleStderrAsEvents(cmd) // cmd.Stderr
if err != nil {
return err
}
}
func connGetGoos(stdin io.Writer, stdout *bufio.Reader) (string, error) {
- _, err := fmt.Fprintln(stdin, "uname -o")
+ _, err := fmt.Fprintln(stdin, "uname")
if err != nil {
return "", err
}
// NOTE: Adapt helper uploading in dialSSH() when adding new systems
var goos string
switch x {
- case "GNU/Linux":
+ case "Linux":
goos = "linux"
+ case "FreeBSD":
+ goos = "freebsd"
+ case "OpenBSD":
+ goos = "openbsd"
default:
- return "", fmt.Errorf("unsupported OS %q (`uname -o`)", x)
+ return "", fmt.Errorf("unsupported OS %q (`uname`)", x)
}
return goos, nil
}
// NOTE: Adapt cmd/safcm-remote/build.sh when adding new architectures
var goarch string
switch x {
- case "x86_64":
+ case "x86_64", "amd64":
goarch = "amd64"
case "armv7l":
goarch = "armv7l"
ruderich.org/simon / safcm / safcm.git / blobdiff