Implement sshs config generator from known_hosts files

cmd/generate.go

@@ -0,0 +1,184 @@
+package cmd
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"regexp"
+	"strings"
+
+	valid "github.com/asaskevich/govalidator"
+	"github.com/mitchellh/go-homedir"
+	"github.com/quantumsheep/sshconfig"
+	"github.com/spf13/cobra"
+	"github.com/spf13/pflag"
+	"github.com/spf13/viper"
+)
+
+var generateCmd = &cobra.Command{
+	Use:     "generate",
+	Short:   "Generate a ssh configuration from different sources",
+	Version: rootCmd.Version,
+	Run:     runGenerate,
+}
+
+func init() {
+	flags := generateCmd.Flags()
+	flags.Bool("known-hosts", false, "Generate from known_hosts file")
+	flags.String("known-hosts-file", "~/.ssh/known_hosts", "Path of known_hosts file")
+	flags.Bool("known-hosts-allow-single-ip", true, "Allow single IP addresses (without hostname)")
+
+	viper.SetDefault("author", "quantumsheep <[email protected]>")
+	viper.SetDefault("license", "MIT")
+}
+
+func runGenerate(cmd *cobra.Command, args []string) {
+	flags := cmd.Flags()
+
+	knownHosts, e := flags.GetBool("known-hosts")
+	if e != nil {
+		log.Fatal(e)
+	}
+
+	if !knownHosts {
+		cmd.Help()
+		os.Exit(0)
+	}
+
+	configs := make([]*KnownHostConfig, 0)
+
+	if knownHosts {
+		configs = append(configs, generateFromKnownHosts(flags)...)
+	}
+
+	config := strings.Join(KnownHostConfigStrings(KnownHostConfigUniques(configs)), "\n\n")
+	fmt.Println(config)
+}
+
+func generateFromKnownHosts(flags *pflag.FlagSet) []*KnownHostConfig {
+	knownHostsFile := "~/.ssh/known_hosts"
+
+	if str, e := flags.GetString("known-hosts-file"); e == nil && str != "" {
+		knownHostsFile = str
+	}
+
+	knownHostsFile, e := homedir.Expand(knownHostsFile)
+	if e != nil {
+		log.Fatal(e)
+	}
+
+	// open file
+	bytes, e := os.ReadFile(knownHostsFile)
+	if e != nil {
+		log.Fatal(e)
+	}
+
+	data := string(bytes)
+	lines := strings.Split(data, "\n")
+
+	rx := regexp.MustCompile(`^(\[(?P<Host>.*?)\]:(?P<Port>\d+))|(?P<SingleHost>.*?)$`)
+
+	configs := make([]*KnownHostConfig, 0)
+
+	for _, line := range lines {
+		if line == "" {
+			continue
+		}
+
+		lineConfigs := make([]*KnownHostConfig, 0)
+
+		targets := strings.Split(strings.Split(line, " ")[0], ",")
+		for _, target := range targets {
+			config := NewKnownHostConfig()
+
+			matches := rx.FindStringSubmatch(target)
+
+			if host := matches[rx.SubexpIndex("Host")]; host != "" {
+				port := matches[rx.SubexpIndex("Port")]
+
+				config.Host = host + ":" + port
+				config.HostName = host
+				config.Port = port
+			} else if host := matches[rx.SubexpIndex("SingleHost")]; host != "" {
+				config.Host = host
+				config.HostName = host
+			}
+
+			lineConfigs = append(lineConfigs, config)
+		}
+
+		allowSingleIp, e := flags.GetBool("known-hosts-allow-single-ip")
+		if e != nil {
+			log.Fatal(e)
+		}
+
+		var config *KnownHostConfig = nil
+
+		// Select the first config with a valid domain name (defaults to the first config)
+		for _, lineConfig := range lineConfigs {
+			if valid.IsDNSName(lineConfig.HostName) {
+				config = lineConfig
+				break
+			}
+		}
+
+		if config != nil {
+			configs = append(configs, config)
+		} else if allowSingleIp && len(lineConfigs) > 0 {
+			configs = append(configs, lineConfigs[0])
+		}
+	}
+
+	return configs
+}
+
+type KnownHostConfig struct {
+	*sshconfig.SSHHost
+
+	Host string
+	Port string
+}
+
+func NewKnownHostConfig() *KnownHostConfig {
+	return &KnownHostConfig{
+		SSHHost: &sshconfig.SSHHost{},
+		Port:    "22",
+	}
+}
+
+func (c *KnownHostConfig) String() string {
+	return "Host " + c.Host +
+		"\n  Hostname " + c.HostName +
+		"\n  Port " + c.Port
+}
+
+func KnownHostConfigStrings(configs []*KnownHostConfig) []string {
+	list := make([]string, 0)
+
+	for _, item := range configs {
+		list = append(list, item.String())
+	}
+
+	return list
+}
+
+func KnownHostConfigUniques(configs []*KnownHostConfig) []*KnownHostConfig {
+	list := make([]*KnownHostConfig, 0)
+
+	for _, item := range configs {
+		found := false
+
+		for _, item2 := range list {
+			if item.Host == item2.Host && item.HostName == item2.HostName && item.Port == item2.Port {
+				found = true
+				break
+			}
+		}
+
+		if !found {
+			list = append(list, item)
+		}
+	}
+
+	return list
+}

cmd/root.go

@@ -22,10 +22,29 @@ var rootCmd = &cobra.Command{
 	Use:     "sshs",
 	Short:   "ssh clients manager",
 	Version: Version,
-	Run:     run,
+	Run:     runRoot,
 }
 
-func run(cmd *cobra.Command, args []string) {
+func init() {
+	flags := rootCmd.Flags()
+	flags.StringP("search", "s", "", "Host search filter")
+	flags.StringP("config", "c", "~/.ssh/config", "SSH config file")
+	flags.BoolP("proxy", "p", false, "Display full ProxyCommand")
+
+	viper.SetDefault("author", "quantumsheep <[email protected]>")
+	viper.SetDefault("license", "MIT")
+
+	rootCmd.AddCommand(generateCmd)
+}
+
+func Execute() {
+	if err := rootCmd.Execute(); err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+}
+
+func runRoot(cmd *cobra.Command, args []string) {
 	flags := cmd.Flags()
 
 	sshConfigPath, e := flags.GetString("config")
@@ -95,20 +114,3 @@ func createFileRecursive(filename string) error {
 
 	return nil
 }
-
-func Execute() {
-	if e := rootCmd.Execute(); e != nil {
-		fmt.Println(e)
-		os.Exit(1)
-	}
-}
-
-func init() {
-	flags := rootCmd.PersistentFlags()
-	flags.StringP("search", "s", "", "Host search filter")
-	flags.StringP("config", "c", "~/.ssh/config", "SSH config file")
-	flags.BoolP("proxy", "p", false, "Display full ProxyCommand")
-
-	viper.SetDefault("author", "quantumsheep <[email protected]>")
-	viper.SetDefault("license", "MIT")
-}

go.mod

@@ -1,6 +1,6 @@
 module github.com/quantumsheep/sshs
 
-go 1.17
+go 1.18
 
 require (
 	github.com/asaskevich/govalidator v0.0.0-20210307081110-f21760c49a8d
@@ -9,6 +9,7 @@ require (
 	github.com/quantumsheep/sshconfig v1.1.0
 	github.com/rivo/tview v0.0.0-20220129131435-1f7581b67bd1
 	github.com/spf13/cobra v1.3.0
+	github.com/spf13/pflag v1.0.5
 	github.com/spf13/viper v1.10.1
 )
 
@@ -26,7 +27,6 @@ require (
 	github.com/spf13/afero v1.6.0 // indirect
 	github.com/spf13/cast v1.4.1 // indirect
 	github.com/spf13/jwalterweatherman v1.1.0 // indirect
-	github.com/spf13/pflag v1.0.5 // indirect
 	github.com/subosito/gotenv v1.2.0 // indirect
 	golang.org/x/sys v0.0.0-20211210111614-af8b64212486 // indirect
 	golang.org/x/term v0.0.0-20210220032956-6a3ed077a48d // indirect

go.sum

@@ -198,7 +198,6 @@ github.com/googleapis/gax-go/v2 v2.1.0/go.mod h1:Q3nei7sK6ybPYH7twZdmQpAd1MKb7pf
 github.com/googleapis/gax-go/v2 v2.1.1/go.mod h1:hddJymUZASv3XPyGkUpKj8pPO47Rmb0eJc8R6ouapiM=
 github.com/grpc-ecosystem/grpc-gateway v1.16.0/go.mod h1:BDjrQk3hbvj6Nolgz8mAMFbcEtjT1g+wF4CSlocrBnw=
 github.com/hashicorp/consul/api v1.11.0/go.mod h1:XjsvQN+RJGWI2TWy1/kqaE16HrR2J/FWgkYjdZQsX9M=
-github.com/hashicorp/consul/api v1.12.0/go.mod h1:6pVBMo0ebnYdt2S3H87XhekM/HHrUoTD2XXb/VrZVy0=
 github.com/hashicorp/consul/sdk v0.8.0/go.mod h1:GBvyrGALthsZObzUGsfgHZQDXjg4lOjagTIwIR1vPms=
 github.com/hashicorp/errwrap v1.0.0/go.mod h1:YH+1FKiLXxHSkmPseP+kNlulaMuP3n2brvKWEqk/Jc4=
 github.com/hashicorp/go-cleanhttp v0.5.0/go.mod h1:JpRdi6/HCYpAwUzNwuwqhbovhLtngrth3wmdIIUrZ80=
@@ -322,7 +321,6 @@ github.com/rogpeppe/go-internal v1.3.0/go.mod h1:M8bDsm7K2OlrFYOpmOWEs/qY81heoFR
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/ryanuber/columnize v0.0.0-20160712163229-9b3edd62028f/go.mod h1:sm1tb6uqfes/u+d4ooFouqFdy9/2g9QGwK3SQygK0Ts=
 github.com/sagikazarmark/crypt v0.3.0/go.mod h1:uD/D+6UF4SrIR1uGEv7bBNkNqLGqUr43MRiaGWX1Nig=
-github.com/sagikazarmark/crypt v0.4.0/go.mod h1:ALv2SRj7GxYV4HO9elxH9nS6M9gW+xDNxqmyJ6RfDFM=
 github.com/sean-/seed v0.0.0-20170313163322-e2103e2c3529/go.mod h1:DxrIzT+xaE7yg65j358z/aeFdxmN0P9QXhEzd20vsDc=
 github.com/sirupsen/logrus v1.2.0/go.mod h1:LxeOpSwHxABJmUn/MG1IvRgCAasNZTLOkJPxbbu5VWo=
 github.com/sirupsen/logrus v1.4.2/go.mod h1:tLMulIdttU9McNUspp0xgXVQah82FyeX6MwdIuYE2rE=
@@ -662,7 +660,6 @@ google.golang.org/api v0.57.0/go.mod h1:dVPlbZyBo2/OjBpmvNdpn2GRm6rPy75jyU7bmhdr
 google.golang.org/api v0.59.0/go.mod h1:sT2boj7M9YJxZzgeZqXogmhfmRWDtPzT31xkieUbuZU=
 google.golang.org/api v0.61.0/go.mod h1:xQRti5UdCmoCEqFxcz93fTl338AVqDgyaDRuOZ3hg9I=
 google.golang.org/api v0.62.0/go.mod h1:dKmwPCydfsad4qCH08MSdgWjfHOyfpd4VtDGgRFdavw=
-google.golang.org/api v0.63.0/go.mod h1:gs4ij2ffTRXwuzzgJl/56BdwJaA194ijkfn++9tDuPo=
 google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
 google.golang.org/appengine v1.4.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
 google.golang.org/appengine v1.5.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
@@ -760,7 +757,6 @@ google.golang.org/grpc v1.39.1/go.mod h1:PImNr+rS9TWYb2O4/emRugxiyHZ5JyHW5F+RPnD
 google.golang.org/grpc v1.40.0/go.mod h1:ogyxbiOoUXAkP+4+xa6PZSE9DZgIHtSpzjDTB9KAK34=
 google.golang.org/grpc v1.40.1/go.mod h1:ogyxbiOoUXAkP+4+xa6PZSE9DZgIHtSpzjDTB9KAK34=
 google.golang.org/grpc v1.42.0/go.mod h1:k+4IHHFw41K8+bbowsex27ge2rCb65oeWqe4jJ590SU=
-google.golang.org/grpc v1.43.0/go.mod h1:k+4IHHFw41K8+bbowsex27ge2rCb65oeWqe4jJ590SU=
 google.golang.org/grpc/cmd/protoc-gen-go-grpc v1.1.0/go.mod h1:6Kw0yEErY5E/yWrBtf03jp27GLLJujG4z/JK95pnjjw=
 google.golang.org/protobuf v0.0.0-20200109180630-ec00e32a8dfd/go.mod h1:DFci5gLYBciE7Vtevhsrf46CRTquxDuWsQurQQe4oz8=
 google.golang.org/protobuf v0.0.0-20200221191635-4d8936d0db64/go.mod h1:kwYJMbMJ01Woi6D6+Kah6886xMZcty6N08ah7+eCXa0=