1 files changed, 97 insertions, 0 deletions
diff --git a/contrib/persistent-https/socket.go b/contrib/persistent-https/socket.go
new file mode 100644
index 0000000000..193b911dd1
--- /dev/null
+++ b/contrib/persistent-https/socket.go
@@ -0,0 +1,97 @@
+// Copyright 2012 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+import (
+	"fmt"
+	"log"
+	"net"
+	"os"
+	"path/filepath"
+	"syscall"
+)
+
+// A Socket is a wrapper around a Unix socket that verifies directory
+// permissions.
+type Socket struct {
+	Dir string
+}
+
+func defaultDir() string {
+	sockPath := ".git-credential-cache"
+	if home := os.Getenv("HOME"); home != "" {
+		return filepath.Join(home, sockPath)
+	}
+	log.Printf("socket: cannot find HOME path. using relative directory %q for socket", sockPath)
+	return sockPath
+}
+
+// DefaultSocket is a Socket in the $HOME/.git-credential-cache directory.
+var DefaultSocket = Socket{Dir: defaultDir()}
+
+// Listen announces the local network address of the unix socket. The
+// permissions on the socket directory are verified before attempting
+// the actual listen.
+func (s Socket) Listen() (net.Listener, error) {
+	network, addr := "unix", s.Path()
+	if err := s.mkdir(); err != nil {
+		return nil, &net.OpError{Op: "listen", Net: network, Addr: &net.UnixAddr{Name: addr, Net: network}, Err: err}
+	}
+	return net.Listen(network, addr)
+}
+
+// Dial connects to the unix socket. The permissions on the socket directory
+// are verified before attempting the actual dial.
+func (s Socket) Dial() (net.Conn, error) {
+	network, addr := "unix", s.Path()
+	if err := s.checkPermissions(); err != nil {
+		return nil, &net.OpError{Op: "dial", Net: network, Addr: &net.UnixAddr{Name: addr, Net: network}, Err: err}
+	}
+	return net.Dial(network, addr)
+}
+
+// Path returns the fully specified file name of the unix socket.
+func (s Socket) Path() string {
+	return filepath.Join(s.Dir, "persistent-https-proxy-socket")
+}
+
+func (s Socket) mkdir() error {
+	if err := s.checkPermissions(); err == nil {
+		return nil
+	} else if !os.IsNotExist(err) {
+		return err
+	}
+	if err := os.MkdirAll(s.Dir, 0700); err != nil {
+		return err
+	}
+	return s.checkPermissions()
+}
+
+func (s Socket) checkPermissions() error {
+	fi, err := os.Stat(s.Dir)
+	if err != nil {
+		return err
+	}
+	if !fi.IsDir() {
+		return fmt.Errorf("socket: got file, want directory for %q", s.Dir)
+	}
+	if fi.Mode().Perm() != 0700 {
+		return fmt.Errorf("socket: got perm %o, want 700 for %q", fi.Mode().Perm(), s.Dir)
+	}
+	if st := fi.Sys().(*syscall.Stat_t); int(st.Uid) != os.Getuid() {
+		return fmt.Errorf("socket: got uid %d, want %d for %q", st.Uid, os.Getuid(), s.Dir)
+	}
+	return nil
+}