Add Chef package registry (#22554)

This PR implements a [Chef registry](https://chef.io/) to manage
cookbooks. This package type was a bit complicated because Chef uses RSA
signed requests as authentication with the registry.


![grafik](https://user-images.githubusercontent.com/1666336/213747995-46819fd8-c3d6-45a2-afd4-a4c3c8505a4a.png)


![grafik](https://user-images.githubusercontent.com/1666336/213748145-d01c9e81-d4dd-41e3-a3cc-8241862c3166.png)

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

6 files changed, 239 insertions, 10 deletions

diff --git a/modules/activitypub/user_settings.go b/modules/activitypub/user_settings.go
index ec5fa59842..2d156c17e6 100644
--- a/modules/activitypub/user_settings.go
+++ b/modules/activitypub/user_settings.go
@@ -5,8 +5,11 @@ package activitypub
 
 import (
 	user_model "code.gitea.io/gitea/models/user"
+	"code.gitea.io/gitea/modules/util"
 )
 
+const rsaBits = 2048
+
 // GetKeyPair function returns a user's private and public keys
 func GetKeyPair(user *user_model.User) (pub, priv string, err error) {
 	var settings map[string]*user_model.Setting
@@ -14,7 +17,7 @@ func GetKeyPair(user *user_model.User) (pub, priv string, err error) {
 	if err != nil {
 		return
 	} else if len(settings) == 0 {
-		if priv, pub, err = GenerateKeyPair(); err != nil {
+		if priv, pub, err = util.GenerateKeyPair(rsaBits); err != nil {
 			return
 		}
 		if err = user_model.SetUserSetting(user.ID, user_model.UserActivityPubPrivPem, priv); err != nil {
diff --git a/modules/packages/chef/metadata.go b/modules/packages/chef/metadata.go
new file mode 100644
index 0000000000..a1c91870c2
--- /dev/null
+++ b/modules/packages/chef/metadata.go
@@ -0,0 +1,134 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package chef
+
+import (
+	"archive/tar"
+	"compress/gzip"
+	"io"
+	"regexp"
+	"strings"
+
+	"code.gitea.io/gitea/modules/json"
+	"code.gitea.io/gitea/modules/util"
+	"code.gitea.io/gitea/modules/validation"
+)
+
+const (
+	KeyBits          = 4096
+	SettingPublicPem = "chef.public_pem"
+)
+
+var (
+	ErrMissingMetadataFile = util.NewInvalidArgumentErrorf("metadata.json file is missing")
+	ErrInvalidName         = util.NewInvalidArgumentErrorf("package name is invalid")
+	ErrInvalidVersion      = util.NewInvalidArgumentErrorf("package version is invalid")
+
+	namePattern    = regexp.MustCompile(`\A\S+\z`)
+	versionPattern = regexp.MustCompile(`\A\d+\.\d+(?:\.\d+)?\z`)
+)
+
+// Package represents a Chef package
+type Package struct {
+	Name     string
+	Version  string
+	Metadata *Metadata
+}
+
+// Metadata represents the metadata of a Chef package
+type Metadata struct {
+	Description     string            `json:"description,omitempty"`
+	LongDescription string            `json:"long_description,omitempty"`
+	Author          string            `json:"author,omitempty"`
+	License         string            `json:"license,omitempty"`
+	RepositoryURL   string            `json:"repository_url,omitempty"`
+	Dependencies    map[string]string `json:"dependencies,omitempty"`
+}
+
+type chefMetadata struct {
+	Name               string            `json:"name"`
+	Description        string            `json:"description"`
+	LongDescription    string            `json:"long_description"`
+	Maintainer         string            `json:"maintainer"`
+	MaintainerEmail    string            `json:"maintainer_email"`
+	License            string            `json:"license"`
+	Platforms          map[string]string `json:"platforms"`
+	Dependencies       map[string]string `json:"dependencies"`
+	Providing          map[string]string `json:"providing"`
+	Recipes            map[string]string `json:"recipes"`
+	Version            string            `json:"version"`
+	SourceURL          string            `json:"source_url"`
+	IssuesURL          string            `json:"issues_url"`
+	Privacy            bool              `json:"privacy"`
+	ChefVersions       [][]string        `json:"chef_versions"`
+	Gems               [][]string        `json:"gems"`
+	EagerLoadLibraries bool              `json:"eager_load_libraries"`
+}
+
+// ParsePackage parses the Chef package file
+func ParsePackage(r io.Reader) (*Package, error) {
+	gzr, err := gzip.NewReader(r)
+	if err != nil {
+		return nil, err
+	}
+	defer gzr.Close()
+
+	tr := tar.NewReader(gzr)
+	for {
+		hd, err := tr.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return nil, err
+		}
+
+		if hd.Typeflag != tar.TypeReg {
+			continue
+		}
+
+		if strings.Count(hd.Name, "/") != 1 {
+			continue
+		}
+
+		if hd.FileInfo().Name() == "metadata.json" {
+			return ParseChefMetadata(tr)
+		}
+	}
+
+	return nil, ErrMissingMetadataFile
+}
+
+// ParseChefMetadata parses a metadata.json file to retrieve the metadata of a Chef package
+func ParseChefMetadata(r io.Reader) (*Package, error) {
+	var cm chefMetadata
+	if err := json.NewDecoder(r).Decode(&cm); err != nil {
+		return nil, err
+	}
+
+	if !namePattern.MatchString(cm.Name) {
+		return nil, ErrInvalidName
+	}
+
+	if !versionPattern.MatchString(cm.Version) {
+		return nil, ErrInvalidVersion
+	}
+
+	if !validation.IsValidURL(cm.SourceURL) {
+		cm.SourceURL = ""
+	}
+
+	return &Package{
+		Name:    cm.Name,
+		Version: cm.Version,
+		Metadata: &Metadata{
+			Description:     cm.Description,
+			LongDescription: cm.LongDescription,
+			Author:          cm.Maintainer,
+			License:         cm.License,
+			RepositoryURL:   cm.SourceURL,
+			Dependencies:    cm.Dependencies,
+		},
+	}, nil
+}
diff --git a/modules/packages/chef/metadata_test.go b/modules/packages/chef/metadata_test.go
new file mode 100644
index 0000000000..6def4162a9
--- /dev/null
+++ b/modules/packages/chef/metadata_test.go
@@ -0,0 +1,92 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package chef
+
+import (
+	"archive/tar"
+	"bytes"
+	"compress/gzip"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+const (
+	packageName          = "gitea"
+	packageVersion       = "1.0.1"
+	packageAuthor        = "KN4CK3R"
+	packageDescription   = "Package Description"
+	packageRepositoryURL = "https://gitea.io/gitea/gitea"
+)
+
+func TestParsePackage(t *testing.T) {
+	t.Run("MissingMetadataFile", func(t *testing.T) {
+		var buf bytes.Buffer
+		zw := gzip.NewWriter(&buf)
+		tw := tar.NewWriter(zw)
+		tw.Close()
+		zw.Close()
+
+		p, err := ParsePackage(&buf)
+		assert.Nil(t, p)
+		assert.ErrorIs(t, err, ErrMissingMetadataFile)
+	})
+
+	t.Run("Valid", func(t *testing.T) {
+		var buf bytes.Buffer
+		zw := gzip.NewWriter(&buf)
+		tw := tar.NewWriter(zw)
+
+		content := `{"name":"` + packageName + `","version":"` + packageVersion + `"}`
+
+		hdr := &tar.Header{
+			Name: packageName + "/metadata.json",
+			Mode: 0o600,
+			Size: int64(len(content)),
+		}
+		tw.WriteHeader(hdr)
+		tw.Write([]byte(content))
+
+		tw.Close()
+		zw.Close()
+
+		p, err := ParsePackage(&buf)
+		assert.NoError(t, err)
+		assert.NotNil(t, p)
+		assert.Equal(t, packageName, p.Name)
+		assert.Equal(t, packageVersion, p.Version)
+		assert.NotNil(t, p.Metadata)
+	})
+}
+
+func TestParseChefMetadata(t *testing.T) {
+	t.Run("InvalidName", func(t *testing.T) {
+		for _, name := range []string{" test", "test "} {
+			p, err := ParseChefMetadata(strings.NewReader(`{"name":"` + name + `","version":"1.0.0"}`))
+			assert.Nil(t, p)
+			assert.ErrorIs(t, err, ErrInvalidName)
+		}
+	})
+
+	t.Run("InvalidVersion", func(t *testing.T) {
+		for _, version := range []string{"1", "1.2.3.4", "1.0.0 "} {
+			p, err := ParseChefMetadata(strings.NewReader(`{"name":"test","version":"` + version + `"}`))
+			assert.Nil(t, p)
+			assert.ErrorIs(t, err, ErrInvalidVersion)
+		}
+	})
+
+	t.Run("Valid", func(t *testing.T) {
+		p, err := ParseChefMetadata(strings.NewReader(`{"name":"` + packageName + `","version":"` + packageVersion + `","description":"` + packageDescription + `","maintainer":"` + packageAuthor + `","source_url":"` + packageRepositoryURL + `"}`))
+		assert.NotNil(t, p)
+		assert.NoError(t, err)
+
+		assert.Equal(t, packageName, p.Name)
+		assert.Equal(t, packageVersion, p.Version)
+		assert.Equal(t, packageDescription, p.Metadata.Description)
+		assert.Equal(t, packageAuthor, p.Metadata.Author)
+		assert.Equal(t, packageRepositoryURL, p.Metadata.RepositoryURL)
+	})
+}
diff --git a/modules/setting/packages.go b/modules/setting/packages.go
index 190c17dd8f..84da4eb53e 100644
--- a/modules/setting/packages.go
+++ b/modules/setting/packages.go
@@ -26,6 +26,7 @@ var (
 		LimitTotalOwnerCount int64
 		LimitTotalOwnerSize  int64
 		LimitSizeCargo       int64
+		LimitSizeChef        int64
 		LimitSizeComposer    int64
 		LimitSizeConan       int64
 		LimitSizeConda       int64
@@ -67,6 +68,7 @@ func newPackages() {
 
 	Packages.LimitTotalOwnerSize = mustBytes(sec, "LIMIT_TOTAL_OWNER_SIZE")
 	Packages.LimitSizeCargo = mustBytes(sec, "LIMIT_SIZE_CARGO")
+	Packages.LimitSizeChef = mustBytes(sec, "LIMIT_SIZE_CHEF")
 	Packages.LimitSizeComposer = mustBytes(sec, "LIMIT_SIZE_COMPOSER")
 	Packages.LimitSizeConan = mustBytes(sec, "LIMIT_SIZE_CONAN")
 	Packages.LimitSizeConda = mustBytes(sec, "LIMIT_SIZE_CONDA")
diff --git a/modules/activitypub/keypair.go b/modules/util/keypair.go
index 299bdc43e3..5a3ce715a4 100644
--- a/modules/activitypub/keypair.go
+++ b/modules/util/keypair.go
@@ -1,7 +1,7 @@
 // Copyright 2021 The Gitea Authors. All rights reserved.
 // SPDX-License-Identifier: MIT
 
-package activitypub
+package util
 
 import (
 	"crypto/rand"
@@ -10,11 +10,9 @@ import (
 	"encoding/pem"
 )
 
-const rsaBits = 2048
-
-// GenerateKeyPair generates a public and private keypair for signing actions by users for activitypub purposes
-func GenerateKeyPair() (string, string, error) {
-	priv, _ := rsa.GenerateKey(rand.Reader, rsaBits)
+// GenerateKeyPair generates a public and private keypair
+func GenerateKeyPair(bits int) (string, string, error) {
+	priv, _ := rsa.GenerateKey(rand.Reader, bits)
 	privPem, err := pemBlockForPriv(priv)
 	if err != nil {
 		return "", "", err
diff --git a/modules/activitypub/keypair_test.go b/modules/util/keypair_test.go
index 888254c9da..c6f68c845a 100644
--- a/modules/activitypub/keypair_test.go
+++ b/modules/util/keypair_test.go
@@ -1,7 +1,7 @@
 // Copyright 2021 The Gitea Authors. All rights reserved.
 // SPDX-License-Identifier: MIT
 
-package activitypub
+package util
 
 import (
 	"crypto"
@@ -17,7 +17,7 @@ import (
 )
 
 func TestKeygen(t *testing.T) {
-	priv, pub, err := GenerateKeyPair()
+	priv, pub, err := GenerateKeyPair(2048)
 	assert.NoError(t, err)
 
 	assert.NotEmpty(t, priv)
@@ -28,7 +28,7 @@ func TestKeygen(t *testing.T) {
 }
 
 func TestSignUsingKeys(t *testing.T) {
-	priv, pub, err := GenerateKeyPair()
+	priv, pub, err := GenerateKeyPair(2048)
 	assert.NoError(t, err)
 
 	privPem, _ := pem.Decode([]byte(priv))