2 files changed, 26 insertions, 0 deletions
diff --git a/client/client.go b/client/client.go
index 382c53d..e1fb98c 100644
--- a/client/client.go
+++ b/client/client.go
@@ -3,8 +3,10 @@ package client
 import (
 	"bytes"
 	"crypto/tls"
+	"encoding/base64"
 	"encoding/json"
 	"fmt"
+	"io/ioutil"
 	"net/http"
 	"net/url"
 	"path"
@@ -16,6 +18,22 @@ import (
 	"golang.org/x/crypto/ssh/agent"
 )
 
+// SavePublicFiles installs the public part of the cert and key.
+func SavePublicFiles(prefix string, cert *ssh.Certificate, pub ssh.PublicKey) error {
+	if prefix == "" {
+		return nil
+	}
+	pubTxt := ssh.MarshalAuthorizedKey(pub)
+	certPubTxt := []byte(cert.Type() + " " + base64.StdEncoding.EncodeToString(cert.Marshal()))
+
+	if err := ioutil.WriteFile(prefix+".pub", pubTxt, 0644); err != nil {
+		return err
+	}
+	err := ioutil.WriteFile(prefix+"-cert.pub", certPubTxt, 0644)
+
+	return err
+}
+
 // InstallCert adds the private key and signed certificate to the ssh agent.
 func InstallCert(a agent.Agent, cert *ssh.Certificate, key Key) error {
 	t := time.Unix(int64(cert.ValidBefore), 0)
diff --git a/client/config.go b/client/config.go
index 1cc9401..07bbb8c 100644
--- a/client/config.go
+++ b/client/config.go
@@ -1,6 +1,7 @@
 package client
 
 import (
+	"github.com/mitchellh/go-homedir"
 	"github.com/spf13/pflag"
 	"github.com/spf13/viper"
 )
@@ -12,6 +13,7 @@ type Config struct {
 	Keysize                int    `mapstructure:"key_size"`
 	Validity               string `mapstructure:"validity"`
 	ValidateTLSCertificate bool   `mapstructure:"validate_tls_certificate"`
+	PublicFilePrefix       string `mapstructure:"public_file_prefix"`
 }
 
 func setDefaults() {
@@ -19,6 +21,7 @@ func setDefaults() {
 	viper.BindPFlag("key_type", pflag.Lookup("key_type"))
 	viper.BindPFlag("key_size", pflag.Lookup("key_size"))
 	viper.BindPFlag("validity", pflag.Lookup("validity"))
+	viper.BindPFlag("public_file_prefix", pflag.Lookup("public_file_prefix"))
 	viper.SetDefault("validateTLSCertificate", true)
 }
 
@@ -34,5 +37,10 @@ func ReadConfig(path string) (*Config, error) {
 	if err := viper.Unmarshal(c); err != nil {
 		return nil, err
 	}
+	p, err := homedir.Expand(c.PublicFilePrefix)
+	if err != nil {
+		return nil, err
+	}
+	c.PublicFilePrefix = p
 	return c, nil
 }