From ed97ccf535888a5e1fa2cadf42d01089e1192e06 Mon Sep 17 00:00:00 2001
From: Dan Walsh <dwalsh@redhat.com>
Date: Thu, 13 Nov 2014 15:28:39 -0500
Subject: [PATCH] Super Secrets Patch

Docker-DCO-1.1-Signed-off-by: Dan Walsh <dwalsh@redhat.com> (github: rhatdan)
---
 daemon/container.go | 48 +++++++++++++++++++++++++++++-
 daemon/secrets.go   | 86 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 daemon/volumes.go   | 11 +++++++
 graph/graph.go      |  1 +
 4 files changed, 145 insertions(+), 1 deletion(-)
 create mode 100644 daemon/secrets.go

diff --git a/daemon/container.go b/daemon/container.go
index 2ac8316..b754105 100644
--- a/daemon/container.go
+++ b/daemon/container.go
@@ -338,11 +338,28 @@ func (container *Container) Start() (err error) {
 	if err := populateCommand(container, env); err != nil {
 		return err
 	}
+	if err := container.setupSecretFiles(); err != nil {
+		return err
+	}
 	if err := container.setupMounts(); err != nil {
 		return err
 	}
 
-	return container.waitForStart()
+	if err := container.waitForStart(); err != nil {
+		return err
+	}
+
+	// Now the container is running, unmount the secrets on the host
+	secretsPath, err := container.secretsPath()
+	if err != nil {
+		return err
+	}
+
+	if err := syscall.Unmount(secretsPath, syscall.MNT_DETACH); err != nil {
+		return err
+	}
+
+	return nil
 }
 
 func (container *Container) Run() error {
@@ -793,6 +810,10 @@ func (container *Container) jsonPath() (string, error) {
 	return container.getRootResourcePath("config.json")
 }
 
+func (container *Container) secretsPath() (string, error) {
+	return container.getRootResourcePath("secrets")
+}
+
 // This method must be exported to be used from the lxc template
 // This directory is only usable when the container is running
 func (container *Container) RootfsPath() string {
@@ -1064,6 +1085,31 @@ func (container *Container) verifyDaemonSettings() {
 	}
 }
 
+func (container *Container) setupSecretFiles() error {
+	secretsPath, err := container.secretsPath()
+	if err != nil {
+		return err
+	}
+
+	if err := os.MkdirAll(secretsPath, 0700); err != nil {
+		return err
+	}
+
+	if err := syscall.Mount("tmpfs", secretsPath, "tmpfs", uintptr(syscall.MS_NOEXEC|syscall.MS_NOSUID|syscall.MS_NODEV), label.FormatMountLabel("", container.GetMountLabel())); err != nil {
+		return fmt.Errorf("mounting secret tmpfs: %s", err)
+	}
+
+	data, err := getHostSecretData()
+	if err != nil {
+		return err
+	}
+	for _, s := range data {
+		s.SaveTo(secretsPath)
+	}
+
+	return nil
+}
+
 func (container *Container) setupLinkedContainers() ([]string, error) {
 	var (
 		env    []string
diff --git a/daemon/secrets.go b/daemon/secrets.go
new file mode 100644
index 0000000..8bd97a5
--- /dev/null
+++ b/daemon/secrets.go
@@ -0,0 +1,86 @@
+package daemon
+
+import (
+	"io/ioutil"
+	"os"
+	"path/filepath"
+)
+
+type Secret struct {
+	Name      string
+	IsDir     bool
+	HostBased bool
+}
+
+type SecretData struct {
+	Name string
+	Data []byte
+}
+
+func (s SecretData) SaveTo(dir string) error {
+	path := filepath.Join(dir, s.Name)
+	if err := os.MkdirAll(filepath.Dir(path), 0755); err != nil && !os.IsExist(err) {
+		return err
+	}
+	if err := ioutil.WriteFile(path, s.Data, 0755); err != nil {
+		return err
+	}
+	return nil
+}
+
+func readAll(root, prefix string) ([]SecretData, error) {
+	path := filepath.Join(root, prefix)
+
+	data := []SecretData{}
+
+	files, err := ioutil.ReadDir(path)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return data, nil
+		}
+
+		return nil, err
+	}
+
+	for _, f := range files {
+		fileData, err := readFile(root, filepath.Join(prefix, f.Name()))
+		if err != nil {
+			// If the file did not exist, might be a dangling symlink
+			// Ignore the error
+			if os.IsNotExist(err) {
+				continue
+			}
+			return nil, err
+		}
+		data = append(data, fileData...)
+	}
+
+	return data, nil
+}
+
+func readFile(root, name string) ([]SecretData, error) {
+	path := filepath.Join(root, name)
+
+	s, err := os.Stat(path)
+	if err != nil {
+		return nil, err
+	}
+
+	if s.IsDir() {
+		dirData, err := readAll(root, name)
+		if err != nil {
+			return nil, err
+		}
+		return dirData, nil
+	} else {
+		bytes, err := ioutil.ReadFile(path)
+		if err != nil {
+			return nil, err
+		}
+		return []SecretData{{Name: name, Data: bytes}}, nil
+	}
+}
+
+func getHostSecretData() ([]SecretData, error) {
+	return readAll("/usr/share/rhel/secrets", "")
+}
diff --git a/daemon/volumes.go b/daemon/volumes.go
index 6523dae..322d3f4 100644
--- a/daemon/volumes.go
+++ b/daemon/volumes.go
@@ -260,6 +260,17 @@ func (container *Container) setupMounts() error {
 		})
 	}
 
+	secretsPath, err := container.secretsPath()
+	if err != nil {
+		return err
+	}
+
+	mounts = append(mounts, execdriver.Mount{
+		Source:      secretsPath,
+		Destination: "/run/secrets",
+		Writable:    true,
+	})
+
 	container.command.Mounts = mounts
 	return nil
 }
diff --git a/graph/graph.go b/graph/graph.go
index 720f6e6..647b64d 100644
--- a/graph/graph.go
+++ b/graph/graph.go
@@ -242,6 +242,7 @@ func SetupInitLayer(initLayer string) error {
 		"/etc/hostname":    "file",
 		"/dev/console":     "file",
 		"/etc/mtab":        "/proc/mounts",
+		"/run/secrets":     "dir",
 	} {
 		parts := strings.Split(pth, "/")
 		prev := "/"