Save files in local storage as umask (#21198)

Go creates temporary files as 600, but sometimes we want the group to be able to read them (for example,
for another user to back up the storage)

This PR applies the umask to the renamed tmp files in local storage.

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

.woodpecker.yml

@@ -0,0 +1,39 @@
+clone:
+  git:
+    image: woodpeckerci/plugin-git
+    settings:
+      tags: true
+
+pipeline:
+  build:
+    image: docker.io/alpine:3.16
+    commands:
+      - echo "172.17.0.1 alpine.proxy.coso npm.proxy.coso" >> /etc/hosts
+      - echo "http://alpine.proxy.coso/alpine/v3.16/main" > /etc/apk/repositories
+      - echo "http://alpine.proxy.coso/alpine/v3.16/community" >> /etc/apk/repositories
+      - apk add git nodejs npm go make rsync openssh-client-default
+      - npm set registry http://npm.proxy.coso
+
+      - GOOS=linux GOARCH=amd64 LDFLAGS="-linkmode external -extldflags '-static' $LDFLAGS" TAGS="bindata sqlite sqlite_unlock_notify" make build
+
+      - eval $(ssh-agent -s)
+      - echo "$${SSH_KEY}" | tr -d '\r' | ssh-add -
+      - mkdir -p ~/.ssh
+      - echo "[nulo.in]:420,[186.136.121.7]:420 ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBGPkgRVWYcVcgjI0xAjDgZQsYuXU9edcya8zna01ibyUMlfKHIMD9yOoq0R+fQPTCqwiol/2tKMPJ2hlKshc+H8=" > ~/.ssh/known_hosts
+
+      # #!/bin/sh
+      # # Editar en https://gitea.nulo.in/Nulo/gitea si se cambia
+      # bin=/usr/local/bin/gitea
+      # new=/usr/local/bin/gitea.new
+      #
+      # rm "$new"
+      # cat /dev/stdin > "$new" || exit $?
+      # chmod +x "$new" || exit $?
+      # mv "$new" "$bin" || exit $?
+      # sv restart gitea || exit $?
+      - ssh -p420 ci-gitea@nulo.in doas /usr/local/sbin/instalar-gitea < gitea
+    when:
+      branch: gitea.nulo.in
+      event: push
+    secrets:
+      - ssh_key

modules/markup/renderer.go

@@ -315,13 +315,5 @@ func IsMarkupFile(name, markup string) bool {
 // Note that the '.' should be provided in ext, e.g ".md"
 func IsReadmeFile(name string, ext ...string) bool {
 	name = strings.ToLower(name)
-	if len(ext) > 0 {
+	return name == "readme" || strings.Index(name, "readme.") == 0 || strings.Index(name, ".readme.") == 0
-		return name == "readme"+ext[0]
-	}
-	if len(name) < 6 {
-		return false
-	} else if len(name) == 6 {
-		return name == "readme"
-	}
-	return name[:7] == "readme."
 }

modules/storage/local.go

@@ -102,6 +102,10 @@ func (l *LocalStorage) Save(path string, r io.Reader, size int64) (int64, error)
 	if err := util.Rename(tmp.Name(), p); err != nil {
 		return 0, err
 	}
+	// Golang's tmp file (os.CreateTemp) always have 0o600 mode, so we need to change the file to follow the umask (as what Create/MkDir does)
+	if err := util.ApplyUmask(p, os.ModePerm); err != nil {
+		return 0, err
+	}
 
 	tmpRemoved = true
 

modules/util/file_unix.go

@@ -0,0 +1,28 @@
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+//go:build !windows
+
+package util
+
+import (
+	"os"
+
+	"golang.org/x/sys/unix"
+)
+
+var defaultUmask int
+
+func init() {
+	// at the moment, the umask could only be gotten by calling unix.Umask(newUmask)
+	// use 0o077 as temp new umask to reduce the risks if this umask is used anywhere else before the correct umask is recovered
+	tempUmask := 0o077
+	defaultUmask = unix.Umask(tempUmask)
+	unix.Umask(defaultUmask)
+}
+
+func ApplyUmask(f string, newMode os.FileMode) error {
+	mod := newMode & ^os.FileMode(defaultUmask)
+	return os.Chmod(f, mod)
+}

modules/util/file_unix_test.go

@@ -0,0 +1,36 @@
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+//go:build !windows
+
+package util
+
+import (
+	"os"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestApplyUmask(t *testing.T) {
+	f, err := os.CreateTemp(t.TempDir(), "test-filemode-")
+	assert.NoError(t, err)
+
+	err = os.Chmod(f.Name(), 0o777)
+	assert.NoError(t, err)
+	st, err := os.Stat(f.Name())
+	assert.NoError(t, err)
+	assert.EqualValues(t, 0o777, st.Mode().Perm()&0o777)
+
+	oldDefaultUmask := defaultUmask
+	defaultUmask = 0o037
+	defer func() {
+		defaultUmask = oldDefaultUmask
+	}()
+	err = ApplyUmask(f.Name(), os.ModePerm)
+	assert.NoError(t, err)
+	st, err = os.Stat(f.Name())
+	assert.NoError(t, err)
+	assert.EqualValues(t, 0o740, st.Mode().Perm()&0o777)
+}

modules/util/file_windows.go

@@ -0,0 +1,16 @@
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+//go:build windows
+
+package util
+
+import (
+	"os"
+)
+
+func ApplyUmask(f string, newMode os.FileMode) error {
+	// do nothing for Windows, because Windows doesn't use umask
+	return nil
+}