// Copyright (c) 2015-2021 MinIO, Inc. // // This file is part of MinIO Object Storage stack // // This program is free software: you can redistribute it and/or modify // it under the terms of the GNU Affero General Public License as published by // the Free Software Foundation, either version 3 of the License, or // (at your option) any later version. // // This program is distributed in the hope that it will be useful // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU Affero General Public License for more details. // // You should have received a copy of the GNU Affero General Public License // along with this program. If not, see . package logger import ( "bytes" "context" "fmt" "io" "net/http" "strconv" "time" "github.com/minio/minio/internal/logger/message/audit" ) // ResponseWriter - is a wrapper to trap the http response status code. type ResponseWriter struct { http.ResponseWriter StatusCode int // Log body of 4xx or 5xx responses LogErrBody bool // Log body of all responses LogAllBody 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 auditing 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) { 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.WriteHeader(http.StatusOK) } n, err := lrw.ResponseWriter.Write(p) lrw.bytesWritten += n if lrw.TimeToFirstByte == 0 { lrw.TimeToFirstByte = time.Now().UTC().Sub(lrw.StartTime) } if (lrw.LogErrBody && lrw.StatusCode >= http.StatusBadRequest) || lrw.LogAllBody { // 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 - 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.LogErrBody && lrw.StatusCode >= http.StatusBadRequest) || lrw.LogAllBody { return lrw.body.Bytes() } // ... otherwise we return the place holder return BodyPlaceHolder } // WriteHeader - writes http status code func (lrw *ResponseWriter) WriteHeader(code int) { if !lrw.headersLogged { lrw.StatusCode = code 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 } const contextAuditKey = contextKeyType("audit-entry") // SetAuditEntry sets Audit info in the context. func SetAuditEntry(ctx context.Context, audit *audit.Entry) context.Context { if ctx == nil { LogIf(context.Background(), fmt.Errorf("context is nil")) return nil } return context.WithValue(ctx, contextAuditKey, audit) } // GetAuditEntry returns Audit entry if set. func GetAuditEntry(ctx context.Context) *audit.Entry { if ctx != nil { r, ok := ctx.Value(contextAuditKey).(*audit.Entry) if ok { return r } r = &audit.Entry{} SetAuditEntry(ctx, r) return r } return nil } // AuditLog - logs audit logs to all audit targets. func AuditLog(ctx context.Context, w http.ResponseWriter, r *http.Request, reqClaims map[string]interface{}, filterKeys ...string) { // Fast exit if there is not audit target configured if len(AuditTargets) == 0 { return } var entry audit.Entry if w != nil && r != nil { reqInfo := GetReqInfo(ctx) if reqInfo == nil { return } entry = audit.ToEntry(w, r, reqClaims, globalDeploymentID) entry.Trigger = "external-request" for _, filterKey := range filterKeys { delete(entry.ReqClaims, filterKey) delete(entry.ReqQuery, filterKey) delete(entry.ReqHeader, filterKey) delete(entry.RespHeader, filterKey) } var ( statusCode int timeToResponse time.Duration timeToFirstByte time.Duration ) st, ok := w.(*ResponseWriter) if ok { statusCode = st.StatusCode timeToResponse = time.Now().UTC().Sub(st.StartTime) timeToFirstByte = st.TimeToFirstByte } entry.API.Name = reqInfo.API entry.API.Bucket = reqInfo.BucketName entry.API.Object = reqInfo.ObjectName entry.API.Status = http.StatusText(statusCode) entry.API.StatusCode = statusCode entry.API.TimeToResponse = strconv.FormatInt(timeToResponse.Nanoseconds(), 10) + "ns" entry.Tags = reqInfo.GetTagsMap() // ttfb will be recorded only for GET requests, Ignore such cases where ttfb will be empty. if timeToFirstByte != 0 { entry.API.TimeToFirstByte = strconv.FormatInt(timeToFirstByte.Nanoseconds(), 10) + "ns" } } else { auditEntry := GetAuditEntry(ctx) if auditEntry != nil { entry = *auditEntry } } // Send audit logs only to http targets. for _, t := range AuditTargets { _ = t.Send(entry, string(All)) } }