summaryrefslogtreecommitdiffstats
path: root/modules/setting/markup.go
blob: e893c1c2f1ea21d305c01125abfa696f6ae141f2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
// Copyright 2019 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT

package setting

import (
	"regexp"
	"strings"

	"code.gitea.io/gitea/modules/log"
)

// ExternalMarkupRenderers represents the external markup renderers
var (
	ExternalMarkupRenderers    []*MarkupRenderer
	ExternalSanitizerRules     []MarkupSanitizerRule
	MermaidMaxSourceCharacters int
	FilePreviewMaxLines        int
)

const (
	RenderContentModeSanitized   = "sanitized"
	RenderContentModeNoSanitizer = "no-sanitizer"
	RenderContentModeIframe      = "iframe"
)

// Markdown settings
var Markdown = struct {
	EnableHardLineBreakInComments  bool
	EnableHardLineBreakInDocuments bool
	CustomURLSchemes               []string `ini:"CUSTOM_URL_SCHEMES"`
	FileExtensions                 []string
	EnableMath                     bool
}{
	EnableHardLineBreakInComments:  true,
	EnableHardLineBreakInDocuments: false,
	FileExtensions:                 strings.Split(".md,.markdown,.mdown,.mkd,.livemd", ","),
	EnableMath:                     true,
}

// MarkupRenderer defines the external parser configured in ini
type MarkupRenderer struct {
	Enabled              bool
	MarkupName           string
	Command              string
	FileExtensions       []string
	IsInputFile          bool
	NeedPostProcess      bool
	MarkupSanitizerRules []MarkupSanitizerRule
	RenderContentMode    string
}

// MarkupSanitizerRule defines the policy for whitelisting attributes on
// certain elements.
type MarkupSanitizerRule struct {
	Element            string
	AllowAttr          string
	Regexp             *regexp.Regexp
	AllowDataURIImages bool
}

func loadMarkupFrom(rootCfg ConfigProvider) {
	mustMapSetting(rootCfg, "markdown", &Markdown)

	MermaidMaxSourceCharacters = rootCfg.Section("markup").Key("MERMAID_MAX_SOURCE_CHARACTERS").MustInt(5000)
	FilePreviewMaxLines = rootCfg.Section("markup").Key("FILEPREVIEW_MAX_LINES").MustInt(50)
	ExternalMarkupRenderers = make([]*MarkupRenderer, 0, 10)
	ExternalSanitizerRules = make([]MarkupSanitizerRule, 0, 10)

	for _, sec := range rootCfg.Section("markup").ChildSections() {
		name := strings.TrimPrefix(sec.Name(), "markup.")
		if name == "" {
			log.Warn("name is empty, markup " + sec.Name() + "ignored")
			continue
		}

		if name == "sanitizer" || strings.HasPrefix(name, "sanitizer.") {
			newMarkupSanitizer(name, sec)
		} else {
			newMarkupRenderer(name, sec)
		}
	}
}

func newMarkupSanitizer(name string, sec ConfigSection) {
	rule, ok := createMarkupSanitizerRule(name, sec)
	if ok {
		if strings.HasPrefix(name, "sanitizer.") {
			names := strings.SplitN(strings.TrimPrefix(name, "sanitizer."), ".", 2)
			name = names[0]
		}
		for _, renderer := range ExternalMarkupRenderers {
			if name == renderer.MarkupName {
				renderer.MarkupSanitizerRules = append(renderer.MarkupSanitizerRules, rule)
				return
			}
		}
		ExternalSanitizerRules = append(ExternalSanitizerRules, rule)
	}
}

func createMarkupSanitizerRule(name string, sec ConfigSection) (MarkupSanitizerRule, bool) {
	var rule MarkupSanitizerRule

	ok := false
	if sec.HasKey("ALLOW_DATA_URI_IMAGES") {
		rule.AllowDataURIImages = sec.Key("ALLOW_DATA_URI_IMAGES").MustBool(false)
		ok = true
	}

	if sec.HasKey("ELEMENT") || sec.HasKey("ALLOW_ATTR") {
		rule.Element = sec.Key("ELEMENT").Value()
		rule.AllowAttr = sec.Key("ALLOW_ATTR").Value()

		if rule.Element == "" || rule.AllowAttr == "" {
			log.Error("Missing required values from markup.%s. Must have ELEMENT and ALLOW_ATTR defined!", name)
			return rule, false
		}

		regexpStr := sec.Key("REGEXP").Value()
		if regexpStr != "" {
			// Validate when parsing the config that this is a valid regular
			// expression. Then we can use regexp.MustCompile(...) later.
			compiled, err := regexp.Compile(regexpStr)
			if err != nil {
				log.Error("In markup.%s: REGEXP (%s) failed to compile: %v", name, regexpStr, err)
				return rule, false
			}

			rule.Regexp = compiled
		}

		ok = true
	}

	if !ok {
		log.Error("Missing required keys from markup.%s. Must have ELEMENT and ALLOW_ATTR or ALLOW_DATA_URI_IMAGES defined!", name)
		return rule, false
	}

	return rule, true
}

func newMarkupRenderer(name string, sec ConfigSection) {
	extensionReg := regexp.MustCompile(`\.\w`)

	extensions := sec.Key("FILE_EXTENSIONS").Strings(",")
	exts := make([]string, 0, len(extensions))
	for _, extension := range extensions {
		if !extensionReg.MatchString(extension) {
			log.Warn(sec.Name() + " file extension " + extension + " is invalid. Extension ignored")
		} else {
			exts = append(exts, extension)
		}
	}

	if len(exts) == 0 {
		log.Warn(sec.Name() + " file extension is empty, markup " + name + " ignored")
		return
	}

	command := sec.Key("RENDER_COMMAND").MustString("")
	if command == "" {
		log.Warn(" RENDER_COMMAND is empty, markup " + name + " ignored")
		return
	}

	if sec.HasKey("DISABLE_SANITIZER") {
		log.Error("Deprecated setting `[markup.*]` `DISABLE_SANITIZER` present. This fallback will be removed in v1.18.0")
	}

	renderContentMode := sec.Key("RENDER_CONTENT_MODE").MustString(RenderContentModeSanitized)
	if !sec.HasKey("RENDER_CONTENT_MODE") && sec.Key("DISABLE_SANITIZER").MustBool(false) {
		renderContentMode = RenderContentModeNoSanitizer // if only the legacy DISABLE_SANITIZER exists, use it
	}
	if renderContentMode != RenderContentModeSanitized &&
		renderContentMode != RenderContentModeNoSanitizer &&
		renderContentMode != RenderContentModeIframe {
		log.Error("invalid RENDER_CONTENT_MODE: %q, default to %q", renderContentMode, RenderContentModeSanitized)
		renderContentMode = RenderContentModeSanitized
	}

	ExternalMarkupRenderers = append(ExternalMarkupRenderers, &MarkupRenderer{
		Enabled:           sec.Key("ENABLED").MustBool(false),
		MarkupName:        name,
		FileExtensions:    exts,
		Command:           command,
		IsInputFile:       sec.Key("IS_INPUT_FILE").MustBool(false),
		NeedPostProcess:   sec.Key("NEED_POSTPROCESS").MustBool(true),
		RenderContentMode: renderContentMode,
	})
}