From a4275951ba9635e9b7de6a91812b6cc9622c8c9b Mon Sep 17 00:00:00 2001 From: wxiaoguang Date: Fri, 31 May 2024 21:26:01 +0800 Subject: [PATCH] Split sanitizer functions and fine-tune some tests (#31192) --- modules/markup/html_test.go | 16 +- modules/markup/renderer.go | 1 - modules/markup/sanitizer.go | 222 ++---------------- modules/markup/sanitizer_custom.go | 25 ++ modules/markup/sanitizer_default.go | 146 ++++++++++++ ...izer_test.go => sanitizer_default_test.go} | 37 +-- modules/markup/sanitizer_description.go | 37 +++ modules/markup/sanitizer_description_test.go | 31 +++ 8 files changed, 270 insertions(+), 245 deletions(-) create mode 100644 modules/markup/sanitizer_custom.go create mode 100644 modules/markup/sanitizer_default.go rename modules/markup/{sanitizer_test.go => sanitizer_default_test.go} (72%) create mode 100644 modules/markup/sanitizer_description.go create mode 100644 modules/markup/sanitizer_description_test.go diff --git a/modules/markup/html_test.go b/modules/markup/html_test.go index 009139776..e2d08692e 100644 --- a/modules/markup/html_test.go +++ b/modules/markup/html_test.go @@ -169,13 +169,18 @@ func TestRender_links(t *testing.T) { assert.NoError(t, err) assert.Equal(t, strings.TrimSpace(expected), strings.TrimSpace(buffer)) } - // Text that should be turned into URL - defaultCustom := setting.Markdown.CustomURLSchemes + oldCustomURLSchemes := setting.Markdown.CustomURLSchemes + markup.ResetDefaultSanitizerForTesting() + defer func() { + setting.Markdown.CustomURLSchemes = oldCustomURLSchemes + markup.ResetDefaultSanitizerForTesting() + markup.CustomLinkURLSchemes(oldCustomURLSchemes) + }() setting.Markdown.CustomURLSchemes = []string{"ftp", "magnet"} - markup.InitializeSanitizer() markup.CustomLinkURLSchemes(setting.Markdown.CustomURLSchemes) + // Text that should be turned into URL test( "https://www.example.com", `

https://www.example.com

`) @@ -259,11 +264,6 @@ func TestRender_links(t *testing.T) { test( "ftps://gitea.com", `

ftps://gitea.com

`) - - // Restore previous settings - setting.Markdown.CustomURLSchemes = defaultCustom - markup.InitializeSanitizer() - markup.CustomLinkURLSchemes(setting.Markdown.CustomURLSchemes) } func TestRender_email(t *testing.T) { diff --git a/modules/markup/renderer.go b/modules/markup/renderer.go index f836f12ad..44dedf638 100644 --- a/modules/markup/renderer.go +++ b/modules/markup/renderer.go @@ -47,7 +47,6 @@ func Init(ph *ProcessorHelper) { DefaultProcessorHelper = *ph } - NewSanitizer() if len(setting.Markdown.CustomURLSchemes) > 0 { CustomLinkURLSchemes(setting.Markdown.CustomURLSchemes) } diff --git a/modules/markup/sanitizer.go b/modules/markup/sanitizer.go index 570a1da24..391ddad46 100644 --- a/modules/markup/sanitizer.go +++ b/modules/markup/sanitizer.go @@ -5,13 +5,9 @@ package markup import ( - "io" - "net/url" "regexp" "sync" - "code.gitea.io/gitea/modules/setting" - "github.com/microcosm-cc/bluemonday" ) @@ -21,211 +17,35 @@ type Sanitizer struct { defaultPolicy *bluemonday.Policy descriptionPolicy *bluemonday.Policy rendererPolicies map[string]*bluemonday.Policy - init sync.Once + allowAllRegex *regexp.Regexp } var ( - sanitizer = &Sanitizer{} - allowAllRegex = regexp.MustCompile(".+") + defaultSanitizer *Sanitizer + defaultSanitizerOnce sync.Once ) -// NewSanitizer initializes sanitizer with allowed attributes based on settings. -// Multiple calls to this function will only create one instance of Sanitizer during -// entire application lifecycle. -func NewSanitizer() { - sanitizer.init.Do(func() { - InitializeSanitizer() - }) -} - -// InitializeSanitizer (re)initializes the current sanitizer to account for changes in settings -func InitializeSanitizer() { - sanitizer.rendererPolicies = map[string]*bluemonday.Policy{} - sanitizer.defaultPolicy = createDefaultPolicy() - sanitizer.descriptionPolicy = createRepoDescriptionPolicy() - - for name, renderer := range renderers { - sanitizerRules := renderer.SanitizerRules() - if len(sanitizerRules) > 0 { - policy := createDefaultPolicy() - addSanitizerRules(policy, sanitizerRules) - sanitizer.rendererPolicies[name] = policy +func GetDefaultSanitizer() *Sanitizer { + defaultSanitizerOnce.Do(func() { + defaultSanitizer = &Sanitizer{ + rendererPolicies: map[string]*bluemonday.Policy{}, + allowAllRegex: regexp.MustCompile(".+"), } - } -} - -func createDefaultPolicy() *bluemonday.Policy { - policy := bluemonday.UGCPolicy() - - // For JS code copy and Mermaid loading state - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^code-block( is-loading)?$`)).OnElements("pre") - - // For code preview - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^code-preview-[-\w]+( file-content)?$`)).Globally() - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^lines-num$`)).OnElements("td") - policy.AllowAttrs("data-line-number").OnElements("span") - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^lines-code chroma$`)).OnElements("td") - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^code-inner$`)).OnElements("div") - - // For code preview (unicode escape) - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^file-view( unicode-escaped)?$`)).OnElements("table") - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^lines-escape$`)).OnElements("td") - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^toggle-escape-button btn interact-bg$`)).OnElements("a") // don't use button, button might submit a form - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^(ambiguous-code-point|escaped-code-point|broken-code-point)$`)).OnElements("span") - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^char$`)).OnElements("span") - policy.AllowAttrs("data-tooltip-content", "data-escaped").OnElements("span") - - // For color preview - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^color-preview$`)).OnElements("span") - - // For attention - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^attention-header attention-\w+$`)).OnElements("blockquote") - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^attention-\w+$`)).OnElements("strong") - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^attention-icon attention-\w+ svg octicon-[\w-]+$`)).OnElements("svg") - policy.AllowAttrs("viewBox", "width", "height", "aria-hidden").OnElements("svg") - policy.AllowAttrs("fill-rule", "d").OnElements("path") - - // For Chroma markdown plugin - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^(chroma )?language-[\w-]+( display)?( is-loading)?$`)).OnElements("code") - - // Checkboxes - policy.AllowAttrs("type").Matching(regexp.MustCompile(`^checkbox$`)).OnElements("input") - policy.AllowAttrs("checked", "disabled", "data-source-position").OnElements("input") - - // Custom URL-Schemes - if len(setting.Markdown.CustomURLSchemes) > 0 { - policy.AllowURLSchemes(setting.Markdown.CustomURLSchemes...) - } else { - policy.AllowURLSchemesMatching(allowAllRegex) - - // Even if every scheme is allowed, these three are blocked for security reasons - disallowScheme := func(*url.URL) bool { - return false - } - policy.AllowURLSchemeWithCustomPolicy("javascript", disallowScheme) - policy.AllowURLSchemeWithCustomPolicy("vbscript", disallowScheme) - policy.AllowURLSchemeWithCustomPolicy("data", disallowScheme) - } - - // Allow classes for anchors - policy.AllowAttrs("class").Matching(regexp.MustCompile(`ref-issue( ref-external-issue)?`)).OnElements("a") - - // Allow classes for task lists - policy.AllowAttrs("class").Matching(regexp.MustCompile(`task-list-item`)).OnElements("li") - - // Allow classes for org mode list item status. - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^(unchecked|checked|indeterminate)$`)).OnElements("li") - - // Allow icons - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^icon(\s+[\p{L}\p{N}_-]+)+$`)).OnElements("i") - - // Allow classes for emojis - policy.AllowAttrs("class").Matching(regexp.MustCompile(`emoji`)).OnElements("img") - - // Allow icons, emojis, chroma syntax and keyword markup on span - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^((icon(\s+[\p{L}\p{N}_-]+)+)|(emoji)|(language-math display)|(language-math inline))$|^([a-z][a-z0-9]{0,2})$|^` + keywordClass + `$`)).OnElements("span") - - // Allow 'color' and 'background-color' properties for the style attribute on text elements. - policy.AllowStyles("color", "background-color").OnElements("span", "p") - - // Allow generally safe attributes - generalSafeAttrs := []string{ - "abbr", "accept", "accept-charset", - "accesskey", "action", "align", "alt", - "aria-describedby", "aria-hidden", "aria-label", "aria-labelledby", - "axis", "border", "cellpadding", "cellspacing", "char", - "charoff", "charset", "checked", - "clear", "cols", "colspan", "color", - "compact", "coords", "datetime", "dir", - "disabled", "enctype", "for", "frame", - "headers", "height", "hreflang", - "hspace", "ismap", "label", "lang", - "maxlength", "media", "method", - "multiple", "name", "nohref", "noshade", - "nowrap", "open", "prompt", "readonly", "rel", "rev", - "rows", "rowspan", "rules", "scope", - "selected", "shape", "size", "span", - "start", "summary", "tabindex", "target", - "title", "type", "usemap", "valign", "value", - "vspace", "width", "itemprop", - } - - generalSafeElements := []string{ - "h1", "h2", "h3", "h4", "h5", "h6", "h7", "h8", "br", "b", "i", "strong", "em", "a", "pre", "code", "img", "tt", - "div", "ins", "del", "sup", "sub", "p", "ol", "ul", "table", "thead", "tbody", "tfoot", "blockquote", "label", - "dl", "dt", "dd", "kbd", "q", "samp", "var", "hr", "ruby", "rt", "rp", "li", "tr", "td", "th", "s", "strike", "summary", - "details", "caption", "figure", "figcaption", - "abbr", "bdo", "cite", "dfn", "mark", "small", "span", "time", "video", "wbr", - } - - policy.AllowAttrs(generalSafeAttrs...).OnElements(generalSafeElements...) - - policy.AllowAttrs("src", "autoplay", "controls").OnElements("video") - - policy.AllowAttrs("itemscope", "itemtype").OnElements("div") - - // FIXME: Need to handle longdesc in img but there is no easy way to do it - - // Custom keyword markup - addSanitizerRules(policy, setting.ExternalSanitizerRules) - - return policy -} - -// createRepoDescriptionPolicy returns a minimal more strict policy that is used for -// repository descriptions. -func createRepoDescriptionPolicy() *bluemonday.Policy { - policy := bluemonday.NewPolicy() - - // Allow italics and bold. - policy.AllowElements("i", "b", "em", "strong") - - // Allow code. - policy.AllowElements("code") - - // Allow links - policy.AllowAttrs("href", "target", "rel").OnElements("a") - - // Allow classes for emojis - policy.AllowAttrs("class").Matching(regexp.MustCompile(`^emoji$`)).OnElements("img", "span") - policy.AllowAttrs("aria-label").OnElements("span") - - return policy -} - -func addSanitizerRules(policy *bluemonday.Policy, rules []setting.MarkupSanitizerRule) { - for _, rule := range rules { - if rule.AllowDataURIImages { - policy.AllowDataURIImages() - } - if rule.Element != "" { - if rule.Regexp != nil { - policy.AllowAttrs(rule.AllowAttr).Matching(rule.Regexp).OnElements(rule.Element) - } else { - policy.AllowAttrs(rule.AllowAttr).OnElements(rule.Element) + for name, renderer := range renderers { + sanitizerRules := renderer.SanitizerRules() + if len(sanitizerRules) > 0 { + policy := defaultSanitizer.createDefaultPolicy() + defaultSanitizer.addSanitizerRules(policy, sanitizerRules) + defaultSanitizer.rendererPolicies[name] = policy } } - } + defaultSanitizer.defaultPolicy = defaultSanitizer.createDefaultPolicy() + defaultSanitizer.descriptionPolicy = defaultSanitizer.createRepoDescriptionPolicy() + }) + return defaultSanitizer } -// SanitizeDescription sanitizes the HTML generated for a repository description. -func SanitizeDescription(s string) string { - NewSanitizer() - return sanitizer.descriptionPolicy.Sanitize(s) -} - -// Sanitize takes a string that contains a HTML fragment or document and applies policy whitelist. -func Sanitize(s string) string { - NewSanitizer() - return sanitizer.defaultPolicy.Sanitize(s) -} - -// SanitizeReader sanitizes a Reader -func SanitizeReader(r io.Reader, renderer string, w io.Writer) error { - NewSanitizer() - policy, exist := sanitizer.rendererPolicies[renderer] - if !exist { - policy = sanitizer.defaultPolicy - } - return policy.SanitizeReaderToWriter(r, w) +func ResetDefaultSanitizerForTesting() { + defaultSanitizer = nil + defaultSanitizerOnce = sync.Once{} } diff --git a/modules/markup/sanitizer_custom.go b/modules/markup/sanitizer_custom.go new file mode 100644 index 000000000..797897316 --- /dev/null +++ b/modules/markup/sanitizer_custom.go @@ -0,0 +1,25 @@ +// Copyright 2024 The Gitea Authors. All rights reserved. +// SPDX-License-Identifier: MIT + +package markup + +import ( + "code.gitea.io/gitea/modules/setting" + + "github.com/microcosm-cc/bluemonday" +) + +func (st *Sanitizer) addSanitizerRules(policy *bluemonday.Policy, rules []setting.MarkupSanitizerRule) { + for _, rule := range rules { + if rule.AllowDataURIImages { + policy.AllowDataURIImages() + } + if rule.Element != "" { + if rule.Regexp != nil { + policy.AllowAttrs(rule.AllowAttr).Matching(rule.Regexp).OnElements(rule.Element) + } else { + policy.AllowAttrs(rule.AllowAttr).OnElements(rule.Element) + } + } + } +} diff --git a/modules/markup/sanitizer_default.go b/modules/markup/sanitizer_default.go new file mode 100644 index 000000000..669dc24ea --- /dev/null +++ b/modules/markup/sanitizer_default.go @@ -0,0 +1,146 @@ +// Copyright 2024 The Gitea Authors. All rights reserved. +// SPDX-License-Identifier: MIT + +package markup + +import ( + "io" + "net/url" + "regexp" + + "code.gitea.io/gitea/modules/setting" + + "github.com/microcosm-cc/bluemonday" +) + +func (st *Sanitizer) createDefaultPolicy() *bluemonday.Policy { + policy := bluemonday.UGCPolicy() + + // For JS code copy and Mermaid loading state + policy.AllowAttrs("class").Matching(regexp.MustCompile(`^code-block( is-loading)?$`)).OnElements("pre") + + // For code preview + policy.AllowAttrs("class").Matching(regexp.MustCompile(`^code-preview-[-\w]+( file-content)?$`)).Globally() + policy.AllowAttrs("class").Matching(regexp.MustCompile(`^lines-num$`)).OnElements("td") + policy.AllowAttrs("data-line-number").OnElements("span") + policy.AllowAttrs("class").Matching(regexp.MustCompile(`^lines-code chroma$`)).OnElements("td") + policy.AllowAttrs("class").Matching(regexp.MustCompile(`^code-inner$`)).OnElements("div") + + // For code preview (unicode escape) + policy.AllowAttrs("class").Matching(regexp.MustCompile(`^file-view( unicode-escaped)?$`)).OnElements("table") + policy.AllowAttrs("class").Matching(regexp.MustCompile(`^lines-escape$`)).OnElements("td") + policy.AllowAttrs("class").Matching(regexp.MustCompile(`^toggle-escape-button btn interact-bg$`)).OnElements("a") // don't use button, button might submit a form + policy.AllowAttrs("class").Matching(regexp.MustCompile(`^(ambiguous-code-point|escaped-code-point|broken-code-point)$`)).OnElements("span") + policy.AllowAttrs("class").Matching(regexp.MustCompile(`^char$`)).OnElements("span") + policy.AllowAttrs("data-tooltip-content", "data-escaped").OnElements("span") + + // For color preview + policy.AllowAttrs("class").Matching(regexp.MustCompile(`^color-preview$`)).OnElements("span") + + // For attention + policy.AllowAttrs("class").Matching(regexp.MustCompile(`^attention-header attention-\w+$`)).OnElements("blockquote") + policy.AllowAttrs("class").Matching(regexp.MustCompile(`^attention-\w+$`)).OnElements("strong") + policy.AllowAttrs("class").Matching(regexp.MustCompile(`^attention-icon attention-\w+ svg octicon-[\w-]+$`)).OnElements("svg") + policy.AllowAttrs("viewBox", "width", "height", "aria-hidden").OnElements("svg") + policy.AllowAttrs("fill-rule", "d").OnElements("path") + + // For Chroma markdown plugin + policy.AllowAttrs("class").Matching(regexp.MustCompile(`^(chroma )?language-[\w-]+( display)?( is-loading)?$`)).OnElements("code") + + // Checkboxes + policy.AllowAttrs("type").Matching(regexp.MustCompile(`^checkbox$`)).OnElements("input") + policy.AllowAttrs("checked", "disabled", "data-source-position").OnElements("input") + + // Custom URL-Schemes + if len(setting.Markdown.CustomURLSchemes) > 0 { + policy.AllowURLSchemes(setting.Markdown.CustomURLSchemes...) + } else { + policy.AllowURLSchemesMatching(st.allowAllRegex) + + // Even if every scheme is allowed, these three are blocked for security reasons + disallowScheme := func(*url.URL) bool { + return false + } + policy.AllowURLSchemeWithCustomPolicy("javascript", disallowScheme) + policy.AllowURLSchemeWithCustomPolicy("vbscript", disallowScheme) + policy.AllowURLSchemeWithCustomPolicy("data", disallowScheme) + } + + // Allow classes for anchors + policy.AllowAttrs("class").Matching(regexp.MustCompile(`ref-issue( ref-external-issue)?`)).OnElements("a") + + // Allow classes for task lists + policy.AllowAttrs("class").Matching(regexp.MustCompile(`task-list-item`)).OnElements("li") + + // Allow classes for org mode list item status. + policy.AllowAttrs("class").Matching(regexp.MustCompile(`^(unchecked|checked|indeterminate)$`)).OnElements("li") + + // Allow icons + policy.AllowAttrs("class").Matching(regexp.MustCompile(`^icon(\s+[\p{L}\p{N}_-]+)+$`)).OnElements("i") + + // Allow classes for emojis + policy.AllowAttrs("class").Matching(regexp.MustCompile(`emoji`)).OnElements("img") + + // Allow icons, emojis, chroma syntax and keyword markup on span + policy.AllowAttrs("class").Matching(regexp.MustCompile(`^((icon(\s+[\p{L}\p{N}_-]+)+)|(emoji)|(language-math display)|(language-math inline))$|^([a-z][a-z0-9]{0,2})$|^` + keywordClass + `$`)).OnElements("span") + + // Allow 'color' and 'background-color' properties for the style attribute on text elements. + policy.AllowStyles("color", "background-color").OnElements("span", "p") + + // Allow generally safe attributes + generalSafeAttrs := []string{ + "abbr", "accept", "accept-charset", + "accesskey", "action", "align", "alt", + "aria-describedby", "aria-hidden", "aria-label", "aria-labelledby", + "axis", "border", "cellpadding", "cellspacing", "char", + "charoff", "charset", "checked", + "clear", "cols", "colspan", "color", + "compact", "coords", "datetime", "dir", + "disabled", "enctype", "for", "frame", + "headers", "height", "hreflang", + "hspace", "ismap", "label", "lang", + "maxlength", "media", "method", + "multiple", "name", "nohref", "noshade", + "nowrap", "open", "prompt", "readonly", "rel", "rev", + "rows", "rowspan", "rules", "scope", + "selected", "shape", "size", "span", + "start", "summary", "tabindex", "target", + "title", "type", "usemap", "valign", "value", + "vspace", "width", "itemprop", + } + + generalSafeElements := []string{ + "h1", "h2", "h3", "h4", "h5", "h6", "h7", "h8", "br", "b", "i", "strong", "em", "a", "pre", "code", "img", "tt", + "div", "ins", "del", "sup", "sub", "p", "ol", "ul", "table", "thead", "tbody", "tfoot", "blockquote", "label", + "dl", "dt", "dd", "kbd", "q", "samp", "var", "hr", "ruby", "rt", "rp", "li", "tr", "td", "th", "s", "strike", "summary", + "details", "caption", "figure", "figcaption", + "abbr", "bdo", "cite", "dfn", "mark", "small", "span", "time", "video", "wbr", + } + + policy.AllowAttrs(generalSafeAttrs...).OnElements(generalSafeElements...) + + policy.AllowAttrs("src", "autoplay", "controls").OnElements("video") + + policy.AllowAttrs("itemscope", "itemtype").OnElements("div") + + // FIXME: Need to handle longdesc in img but there is no easy way to do it + + // Custom keyword markup + defaultSanitizer.addSanitizerRules(policy, setting.ExternalSanitizerRules) + + return policy +} + +// Sanitize takes a string that contains a HTML fragment or document and applies policy whitelist. +func Sanitize(s string) string { + return GetDefaultSanitizer().defaultPolicy.Sanitize(s) +} + +// SanitizeReader sanitizes a Reader +func SanitizeReader(r io.Reader, renderer string, w io.Writer) error { + policy, exist := GetDefaultSanitizer().rendererPolicies[renderer] + if !exist { + policy = GetDefaultSanitizer().defaultPolicy + } + return policy.SanitizeReaderToWriter(r, w) +} diff --git a/modules/markup/sanitizer_test.go b/modules/markup/sanitizer_default_test.go similarity index 72% rename from modules/markup/sanitizer_test.go rename to modules/markup/sanitizer_default_test.go index b7b8792bd..20370509c 100644 --- a/modules/markup/sanitizer_test.go +++ b/modules/markup/sanitizer_default_test.go @@ -5,18 +5,16 @@ package markup import ( - "html/template" - "strings" "testing" "github.com/stretchr/testify/assert" ) -func Test_Sanitizer(t *testing.T) { - NewSanitizer() +func TestSanitizer(t *testing.T) { testCases := []string{ // Regular `Google`, `Google`, + "<script>alert(document.domain)</script>", "<script>alert(document.domain)</script>", // Code highlighting class ``, ``, @@ -72,34 +70,3 @@ func Test_Sanitizer(t *testing.T) { assert.Equal(t, testCases[i+1], Sanitize(testCases[i])) } } - -func TestDescriptionSanitizer(t *testing.T) { - NewSanitizer() - - testCases := []string{ - `

Title

`, `Title`, - `image`, ``, - `THUMBS UP`, `THUMBS UP`, - `Hello World`, `Hello World`, - `
`, ``, - `https://example.com`, `https://example.com`, - `Important!`, `Important!`, - `
Click me! Nothing to see here.
`, `Click me! Nothing to see here.`, - ``, ``, - `I have a strong opinion about this.`, `I have a strong opinion about this.`, - `Provides alternative wg(8) tool`, `Provides alternative wg(8) tool`, - } - - for i := 0; i < len(testCases); i += 2 { - assert.Equal(t, testCases[i+1], SanitizeDescription(testCases[i])) - } -} - -func TestSanitizeNonEscape(t *testing.T) { - descStr := "<script>alert(document.domain)</script>" - - output := template.HTML(Sanitize(descStr)) - if strings.Contains(string(output), "