builtin/audit: add file audit

builtin/audit/file/backend.go

@@ -0,0 +1,67 @@
+package file
+
+import (
+	"fmt"
+	"os"
+	"sync"
+
+	"github.com/hashicorp/vault/audit"
+	"github.com/hashicorp/vault/logical"
+)
+
+func Factory(conf map[string]string) (audit.Backend, error) {
+	path, ok := conf["path"]
+	if !ok {
+		return nil, fmt.Errorf("path is required")
+	}
+
+	return &Backend{Path: path}, nil
+}
+
+// Backend is the audit backend for the file-based audit store.
+//
+// NOTE: This audit backend is currently very simple: it appends to a file.
+// It doesn't do anything more at the moment to assist with rotation
+// or reset the write cursor, this should be done in the future.
+type Backend struct {
+	Path string
+
+	once sync.Once
+	f    *os.File
+}
+
+func (b *Backend) LogRequest(auth *logical.Auth, req *logical.Request) error {
+	if err := b.open(); err != nil {
+		return err
+	}
+
+	// TODO
+	return nil
+}
+
+func (b *Backend) LogResponse(
+	auth *logical.Auth,
+	req *logical.Request,
+	resp *logical.Response,
+	err error) error {
+	if err := b.open(); err != nil {
+		return err
+	}
+
+	// TODO
+	return nil
+}
+
+func (b *Backend) open() error {
+	if b.f != nil {
+		return nil
+	}
+
+	var err error
+	b.f, err = os.Create(b.Path)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}

command/server.go

@@ -11,6 +11,7 @@ import (
 	"strings"
 
 	"github.com/hashicorp/logutils"
+	"github.com/hashicorp/vault/audit"
 	"github.com/hashicorp/vault/command/server"
 	"github.com/hashicorp/vault/helper/flag-slice"
 	"github.com/hashicorp/vault/helper/gated-writer"
@@ -22,6 +23,7 @@ import (
 
 // ServerCommand is a Command that starts the Vault server.
 type ServerCommand struct {
+	AuditBackends      map[string]audit.Factory
 	CredentialBackends map[string]logical.Factory
 	LogicalBackends    map[string]logical.Factory
 
@@ -91,6 +93,7 @@ func (c *ServerCommand) Run(args []string) int {
 	// Initialize the core
 	core, err := vault.NewCore(&vault.CoreConfig{
 		Physical:           backend,
+		AuditBackends:      c.AuditBackends,
 		CredentialBackends: c.CredentialBackends,
 		LogicalBackends:    c.LogicalBackends,
 		Logger:             logger,

commands.go

@@ -3,9 +3,14 @@ package main
 import (
 	"os"
 
+	auditFile "github.com/hashicorp/vault/builtin/audit/file"
+
 	"github.com/hashicorp/vault/builtin/credential/github"
+
 	"github.com/hashicorp/vault/builtin/logical/aws"
 	"github.com/hashicorp/vault/builtin/logical/consul"
+
+	"github.com/hashicorp/vault/audit"
 	tokenDisk "github.com/hashicorp/vault/builtin/token/disk"
 	"github.com/hashicorp/vault/command"
 	"github.com/hashicorp/vault/logical"
@@ -106,6 +111,9 @@ func init() {
 		"server": func() (cli.Command, error) {
 			return &command.ServerCommand{
 				Meta: meta,
+				AuditBackends: map[string]audit.Factory{
+					"file": auditFile.Factory,
+				},
 				CredentialBackends: map[string]logical.Factory{
 					"github": github.Factory,
 				},