From 7986eba00202be0137c74ab14e0a45b7be255d61 Mon Sep 17 00:00:00 2001
From: 6543 <6543@obermui.de>
Date: Sat, 8 Jan 2022 20:39:52 +0100
Subject: [PATCH] Hide multi line secrets from log (#671)

close #388
---
 pipeline/rpc/line.go                    | 25 ++++++++----------
 pipeline/shared/replace_secrets.go      | 34 +++++++++++++++++++++++++
 pipeline/shared/replace_secrets_test.go | 33 ++++++++++++++++++++++++
 3 files changed, 77 insertions(+), 15 deletions(-)
 create mode 100644 pipeline/shared/replace_secrets.go
 create mode 100644 pipeline/shared/replace_secrets_test.go

diff --git a/pipeline/rpc/line.go b/pipeline/rpc/line.go
index e6ef57e93..a7cd0f342 100644
--- a/pipeline/rpc/line.go
+++ b/pipeline/rpc/line.go
@@ -7,6 +7,8 @@ import (
 	"time"
 
 	"github.com/rs/zerolog/log"
+
+	"github.com/woodpecker-ci/woodpecker/pipeline/shared"
 )
 
 // Identifies the type of line in the logs.
@@ -49,22 +51,14 @@ type LineWriter struct {
 
 // NewLineWriter returns a new line reader.
 func NewLineWriter(peer Peer, id, name string, secret ...string) *LineWriter {
-	w := new(LineWriter)
-	w.peer = peer
-	w.id = id
-	w.name = name
-	w.num = 0
-	w.now = time.Now().UTC()
-
-	var oldnew []string
-	for _, old := range secret {
-		oldnew = append(oldnew, old)
-		oldnew = append(oldnew, "********")
+	return &LineWriter{
+		peer:  peer,
+		id:    id,
+		name:  name,
+		now:   time.Now().UTC(),
+		rep:   shared.NewSecretsReplacer(secret),
+		lines: nil,
 	}
-	if len(oldnew) != 0 {
-		w.rep = strings.NewReplacer(oldnew...)
-	}
-	return w
 }
 
 func (w *LineWriter) Write(p []byte) (n int, err error) {
@@ -72,6 +66,7 @@ func (w *LineWriter) Write(p []byte) (n int, err error) {
 	if w.rep != nil {
 		out = w.rep.Replace(out)
 	}
+	log.Trace().Str("name", w.name).Str("ID", w.id).Msgf("grpc write line: %s", out)
 
 	line := &Line{
 		Out:  out,
diff --git a/pipeline/shared/replace_secrets.go b/pipeline/shared/replace_secrets.go
new file mode 100644
index 000000000..ad0899103
--- /dev/null
+++ b/pipeline/shared/replace_secrets.go
@@ -0,0 +1,34 @@
+// Copyright 2022 Woodpecker Authors
+//
+// 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 shared
+
+import "strings"
+
+func NewSecretsReplacer(secrets []string) *strings.Replacer {
+	var oldnew []string
+	for _, old := range secrets {
+		old = strings.TrimSpace(old)
+		if len(old) == 0 {
+			continue
+		}
+		// since replacer is executed on each line we have to split multi-line-secrets
+		for _, part := range strings.Split(old, "\n") {
+			oldnew = append(oldnew, part)
+			oldnew = append(oldnew, "********")
+		}
+	}
+
+	return strings.NewReplacer(oldnew...)
+}
diff --git a/pipeline/shared/replace_secrets_test.go b/pipeline/shared/replace_secrets_test.go
new file mode 100644
index 000000000..f5a26a140
--- /dev/null
+++ b/pipeline/shared/replace_secrets_test.go
@@ -0,0 +1,33 @@
+package shared
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNewSecretsReplacer(t *testing.T) {
+	tc := []struct {
+		log     string
+		secrets []string
+		expect  string
+	}{{
+		log:     "start log\ndone",
+		secrets: []string{""},
+		expect:  "start log\ndone",
+	}, {
+		log:     `this IS secret: password`,
+		secrets: []string{"password", " IS "},
+		expect:  `this ******** secret: ********`,
+	}, {
+		log:     "start log\ndone\nnow\nan\nmulti line secret!! ;)",
+		secrets: []string{"an\nmulti line secret!!"},
+		expect:  "start log\ndone\nnow\n********\n******** ;)",
+	}}
+
+	for _, c := range tc {
+		rep := NewSecretsReplacer(c.secrets)
+		result := rep.Replace(c.log)
+		assert.EqualValues(t, c.expect, result)
+	}
+}