minio/cmd/logger/audit.go

161 lines
4.5 KiB
Go

/*
* MinIO Cloud Storage, (C) 2018, 2019 MinIO, Inc.
*
* 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 logger
import (
"bytes"
"fmt"
"io"
"net/http"
"time"
"github.com/gorilla/mux"
"github.com/minio/minio/cmd/logger/message/audit"
)
// ResponseWriter - is a wrapper to trap the http response status code.
type ResponseWriter struct {
http.ResponseWriter
StatusCode int
// Response body should be logged
LogBody bool
TimeToFirstByte time.Duration
StartTime time.Time
// number of bytes written
bytesWritten int
// Internal recording buffer
headers bytes.Buffer
body bytes.Buffer
// Indicate if headers are written in the log
headersLogged bool
}
// NewResponseWriter - returns a wrapped response writer to trap
// http status codes for auditiing purposes.
func NewResponseWriter(w http.ResponseWriter) *ResponseWriter {
return &ResponseWriter{
ResponseWriter: w,
StatusCode: http.StatusOK,
StartTime: time.Now().UTC(),
}
}
func (lrw *ResponseWriter) Write(p []byte) (int, error) {
n, err := lrw.ResponseWriter.Write(p)
lrw.bytesWritten += n
if lrw.TimeToFirstByte == 0 {
lrw.TimeToFirstByte = time.Now().UTC().Sub(lrw.StartTime)
}
if !lrw.headersLogged {
// We assume the response code to be '200 OK' when WriteHeader() is not called,
// that way following Golang HTTP response behavior.
lrw.writeHeaders(&lrw.headers, http.StatusOK, lrw.Header())
lrw.headersLogged = true
}
if lrw.StatusCode >= http.StatusBadRequest || lrw.LogBody {
// Always logging error responses.
lrw.body.Write(p)
}
if err != nil {
return n, err
}
return n, err
}
// Write the headers into the given buffer
func (lrw *ResponseWriter) writeHeaders(w io.Writer, statusCode int, headers http.Header) {
n, _ := fmt.Fprintf(w, "%d %s\n", statusCode, http.StatusText(statusCode))
lrw.bytesWritten += n
for k, v := range headers {
n, _ := fmt.Fprintf(w, "%s: %s\n", k, v[0])
lrw.bytesWritten += n
}
}
// BodyPlaceHolder returns a dummy body placeholder
var BodyPlaceHolder = []byte("<BODY>")
// Body - Return response body.
func (lrw *ResponseWriter) Body() []byte {
// If there was an error response or body logging is enabled
// then we return the body contents
if lrw.StatusCode >= http.StatusBadRequest || lrw.LogBody {
return lrw.body.Bytes()
}
// ... otherwise we return the <BODY> place holder
return BodyPlaceHolder
}
// WriteHeader - writes http status code
func (lrw *ResponseWriter) WriteHeader(code int) {
lrw.StatusCode = code
if !lrw.headersLogged {
lrw.writeHeaders(&lrw.headers, code, lrw.ResponseWriter.Header())
lrw.headersLogged = true
}
lrw.ResponseWriter.WriteHeader(code)
}
// Flush - Calls the underlying Flush.
func (lrw *ResponseWriter) Flush() {
lrw.ResponseWriter.(http.Flusher).Flush()
}
// Size - reutrns the number of bytes written
func (lrw *ResponseWriter) Size() int {
return lrw.bytesWritten
}
// AuditTargets is the list of enabled audit loggers
var AuditTargets = []Target{}
// AddAuditTarget adds a new audit logger target to the
// list of enabled loggers
func AddAuditTarget(t Target) {
AuditTargets = append(AuditTargets, t)
}
// AuditLog - logs audit logs to all audit targets.
func AuditLog(w http.ResponseWriter, r *http.Request, api string, reqClaims map[string]interface{}) {
var statusCode int
var timeToResponse time.Duration
var timeToFirstByte time.Duration
lrw, ok := w.(*ResponseWriter)
if ok {
statusCode = lrw.StatusCode
timeToResponse = time.Now().UTC().Sub(lrw.StartTime)
timeToFirstByte = lrw.TimeToFirstByte
}
vars := mux.Vars(r)
bucket := vars["bucket"]
object := vars["object"]
// Send audit logs only to http targets.
for _, t := range AuditTargets {
entry := audit.ToEntry(w, r, reqClaims, globalDeploymentID)
entry.API.Name = api
entry.API.Bucket = bucket
entry.API.Object = object
entry.API.Status = http.StatusText(statusCode)
entry.API.StatusCode = statusCode
entry.API.TimeToFirstByte = timeToFirstByte.String()
entry.API.TimeToResponse = timeToResponse.String()
_ = t.Send(entry)
}
}