Merge pull request #2230 from alissonbrunosa/fix-2179

Add support for ssh_config Include directives

git/remote_test.go

@@ -1,6 +1,17 @@
 package git
 
-import "testing"
+import (
+	"reflect"
+	"testing"
+)
+
+// TODO: extract assertion helpers into a shared package
+func eq(t *testing.T, got interface{}, expected interface{}) {
+	t.Helper()
+	if !reflect.DeepEqual(got, expected) {
+		t.Errorf("expected: %v, got: %v", expected, got)
+	}
+}
 
 func Test_parseRemotes(t *testing.T) {
 	remoteList := []string{

git/ssh_config.go

@@ -13,15 +13,10 @@ import (
 )
 
 var (
-	sshHostRE,
-	sshTokenRE *regexp.Regexp
+	sshConfigLineRE = regexp.MustCompile(`\A\s*(?P<keyword>[A-Za-z][A-Za-z0-9]*)(?:\s+|\s*=\s*)(?P<argument>.+)`)
+	sshTokenRE      = regexp.MustCompile(`%[%h]`)
 )
 
-func init() {
-	sshHostRE = regexp.MustCompile("(?i)^[ \t]*(host|hostname)[ \t]+(.+)$")
-	sshTokenRE = regexp.MustCompile(`%[%h]`)
-}
-
 // SSHAliasMap encapsulates the translation of SSH hostname aliases
 type SSHAliasMap map[string]string
 
@@ -45,6 +40,103 @@ func (m SSHAliasMap) Translator() func(*url.URL) *url.URL {
 	}
 }
 
+type sshParser struct {
+	homeDir string
+
+	aliasMap SSHAliasMap
+	hosts    []string
+
+	open func(string) (io.Reader, error)
+	glob func(string) ([]string, error)
+}
+
+func (p *sshParser) read(fileName string) error {
+	var file io.Reader
+	if p.open == nil {
+		f, err := os.Open(fileName)
+		if err != nil {
+			return err
+		}
+		defer f.Close()
+		file = f
+	} else {
+		var err error
+		file, err = p.open(fileName)
+		if err != nil {
+			return err
+		}
+	}
+
+	if len(p.hosts) == 0 {
+		p.hosts = []string{"*"}
+	}
+
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		m := sshConfigLineRE.FindStringSubmatch(scanner.Text())
+		if len(m) < 3 {
+			continue
+		}
+
+		keyword, arguments := strings.ToLower(m[1]), m[2]
+		switch keyword {
+		case "host":
+			p.hosts = strings.Fields(arguments)
+		case "hostname":
+			for _, host := range p.hosts {
+				for _, name := range strings.Fields(arguments) {
+					if p.aliasMap == nil {
+						p.aliasMap = make(SSHAliasMap)
+					}
+					p.aliasMap[host] = sshExpandTokens(name, host)
+				}
+			}
+		case "include":
+			for _, arg := range strings.Fields(arguments) {
+				path := p.absolutePath(fileName, arg)
+
+				var fileNames []string
+				if p.glob == nil {
+					paths, _ := filepath.Glob(path)
+					for _, p := range paths {
+						if s, err := os.Stat(p); err == nil && !s.IsDir() {
+							fileNames = append(fileNames, p)
+						}
+					}
+				} else {
+					var err error
+					fileNames, err = p.glob(path)
+					if err != nil {
+						continue
+					}
+				}
+
+				for _, fileName := range fileNames {
+					_ = p.read(fileName)
+				}
+			}
+		}
+	}
+
+	return scanner.Err()
+}
+
+func (p *sshParser) absolutePath(parentFile, path string) string {
+	if filepath.IsAbs(path) || strings.HasPrefix(filepath.ToSlash(path), "/") {
+		return path
+	}
+
+	if strings.HasPrefix(path, "~") {
+		return filepath.Join(p.homeDir, strings.TrimPrefix(path, "~"))
+	}
+
+	if strings.HasPrefix(filepath.ToSlash(parentFile), "/etc/ssh") {
+		return filepath.Join("/etc/ssh", path)
+	}
+
+	return filepath.Join(p.homeDir, ".ssh", path)
+}
+
 // ParseSSHConfig constructs a map of SSH hostname aliases based on user and
 // system configuration files
 func ParseSSHConfig() SSHAliasMap {
@@ -52,54 +144,19 @@ func ParseSSHConfig() SSHAliasMap {
 		"/etc/ssh_config",
 		"/etc/ssh/ssh_config",
 	}
+
+	p := sshParser{}
+
 	if homedir, err := homedir.Dir(); err == nil {
 		userConfig := filepath.Join(homedir, ".ssh", "config")
 		configFiles = append([]string{userConfig}, configFiles...)
+		p.homeDir = homedir
 	}
 
-	openFiles := make([]io.Reader, 0, len(configFiles))
 	for _, file := range configFiles {
-		f, err := os.Open(file)
-		if err != nil {
-			continue
-		}
-		defer f.Close()
-		openFiles = append(openFiles, f)
+		_ = p.read(file)
 	}
-	return sshParse(openFiles...)
-}
-
-func sshParse(r ...io.Reader) SSHAliasMap {
-	config := make(SSHAliasMap)
-	for _, file := range r {
-		_ = sshParseConfig(config, file)
-	}
-	return config
-}
-
-func sshParseConfig(c SSHAliasMap, file io.Reader) error {
-	hosts := []string{"*"}
-	scanner := bufio.NewScanner(file)
-	for scanner.Scan() {
-		line := scanner.Text()
-		match := sshHostRE.FindStringSubmatch(line)
-		if match == nil {
-			continue
-		}
-
-		names := strings.Fields(match[2])
-		if strings.EqualFold(match[1], "host") {
-			hosts = names
-		} else {
-			for _, host := range hosts {
-				for _, name := range names {
-					c[host] = sshExpandTokens(name, host)
-				}
-			}
-		}
-	}
-
-	return scanner.Err()
+	return p.aliasMap
 }
 
 func sshExpandTokens(text, host string) string {

git/ssh_config_test.go

@@ -1,31 +1,127 @@
 package git
 
 import (
+	"bytes"
+	"fmt"
+	"io"
 	"net/url"
-	"reflect"
-	"strings"
+	"path/filepath"
 	"testing"
+
+	"github.com/MakeNowJust/heredoc"
 )
 
-// TODO: extract assertion helpers into a shared package
-func eq(t *testing.T, got interface{}, expected interface{}) {
-	t.Helper()
-	if !reflect.DeepEqual(got, expected) {
-		t.Errorf("expected: %v, got: %v", expected, got)
+func Test_sshParser_read(t *testing.T) {
+	testFiles := map[string]string{
+		"/etc/ssh/config": heredoc.Doc(`
+			Include sites/*
+		`),
+		"/etc/ssh/sites/cfg1": heredoc.Doc(`
+			Host s1
+			Hostname=site1.net
+		`),
+		"/etc/ssh/sites/cfg2": heredoc.Doc(`
+			Host s2
+			Hostname = site2.net
+		`),
+		"HOME/.ssh/config": heredoc.Doc(`
+			Host *
+			Host gh gittyhubby
+				Hostname github.com
+				#Hostname example.com
+			Host ex
+			  Include ex_config/*
+		`),
+		"HOME/.ssh/ex_config/ex_cfg": heredoc.Doc(`
+			Hostname example.com
+		`),
+	}
+	globResults := map[string][]string{
+		"/etc/ssh/sites/*":      {"/etc/ssh/sites/cfg1", "/etc/ssh/sites/cfg2"},
+		"HOME/.ssh/ex_config/*": {"HOME/.ssh/ex_config/ex_cfg"},
+	}
+
+	p := &sshParser{
+		homeDir: "HOME",
+		open: func(s string) (io.Reader, error) {
+			if contents, ok := testFiles[filepath.ToSlash(s)]; ok {
+				return bytes.NewBufferString(contents), nil
+			} else {
+				return nil, fmt.Errorf("no test file stub found: %q", s)
+			}
+		},
+		glob: func(p string) ([]string, error) {
+			if results, ok := globResults[filepath.ToSlash(p)]; ok {
+				return results, nil
+			} else {
+				return nil, fmt.Errorf("no glob stubs found: %q", p)
+			}
+		},
+	}
+
+	if err := p.read("/etc/ssh/config"); err != nil {
+		t.Fatalf("read(global config) = %v", err)
+	}
+	if err := p.read("HOME/.ssh/config"); err != nil {
+		t.Fatalf("read(user config) = %v", err)
+	}
+
+	if got := p.aliasMap["gh"]; got != "github.com" {
+		t.Errorf("expected alias %q to expand to %q, got %q", "gh", "github.com", got)
+	}
+	if got := p.aliasMap["gittyhubby"]; got != "github.com" {
+		t.Errorf("expected alias %q to expand to %q, got %q", "gittyhubby", "github.com", got)
+	}
+	if got := p.aliasMap["example.com"]; got != "" {
+		t.Errorf("expected alias %q to expand to %q, got %q", "example.com", "", got)
+	}
+	if got := p.aliasMap["ex"]; got != "example.com" {
+		t.Errorf("expected alias %q to expand to %q, got %q", "ex", "example.com", got)
+	}
+	if got := p.aliasMap["s1"]; got != "site1.net" {
+		t.Errorf("expected alias %q to expand to %q, got %q", "s1", "site1.net", got)
 	}
 }
 
-func Test_sshParse(t *testing.T) {
-	m := sshParse(strings.NewReader(`
-	Host foo bar
-		HostName example.com
-	`), strings.NewReader(`
-	Host bar baz
-	hostname %%%h.net%%
-	`))
-	eq(t, m["foo"], "example.com")
-	eq(t, m["bar"], "%bar.net%")
-	eq(t, m["nonexistent"], "")
+func Test_sshParser_absolutePath(t *testing.T) {
+	dir := "HOME"
+	p := &sshParser{homeDir: dir}
+
+	tests := map[string]struct {
+		parentFile string
+		arg        string
+		want       string
+		wantErr    bool
+	}{
+		"absolute path": {
+			parentFile: "/etc/ssh/ssh_config",
+			arg:        "/etc/ssh/config",
+			want:       "/etc/ssh/config",
+		},
+		"system relative path": {
+			parentFile: "/etc/ssh/config",
+			arg:        "configs/*.conf",
+			want:       filepath.Join("/etc", "ssh", "configs", "*.conf"),
+		},
+		"user relative path": {
+			parentFile: filepath.Join(dir, ".ssh", "ssh_config"),
+			arg:        "configs/*.conf",
+			want:       filepath.Join(dir, ".ssh", "configs/*.conf"),
+		},
+		"shell-like ~ rerefence": {
+			parentFile: filepath.Join(dir, ".ssh", "ssh_config"),
+			arg:        "~/.ssh/*.conf",
+			want:       filepath.Join(dir, ".ssh", "*.conf"),
+		},
+	}
+
+	for name, tt := range tests {
+		t.Run(name, func(t *testing.T) {
+			if got := p.absolutePath(tt.parentFile, tt.arg); got != tt.want {
+				t.Errorf("absolutePath(): %q, wants %q", got, tt.want)
+			}
+		})
+	}
 }
 
 func Test_Translator(t *testing.T) {