From f28da14d98b98e146b2d699ccfed7a6d78847e0b Mon Sep 17 00:00:00 2001
From: vilmibm <nathanielksmith@gmail.com>
Date: Wed, 1 Mar 2023 05:22:09 +0000
Subject: [PATCH] pubkey validation

---
 cmd/welcome/main.go | 57 ++++++++++++++++++++++++++++++++++-----------
 1 file changed, 44 insertions(+), 13 deletions(-)

diff --git a/cmd/welcome/main.go b/cmd/welcome/main.go
index d118c5e..6b39555 100644
--- a/cmd/welcome/main.go
+++ b/cmd/welcome/main.go
@@ -9,6 +9,7 @@ import (
 	"strings"
 
 	"git.tilde.town/tildetown/town/invites"
+	"git.tilde.town/tildetown/town/sshkey"
 	"git.tilde.town/tildetown/town/stats"
 	"github.com/AlecAivazis/survey/v2"
 	"github.com/charmbracelet/lipgloss"
@@ -34,10 +35,9 @@ func surveyIconSet(icons *survey.IconSet) {
 }
 
 func promptCode() (code string, err error) {
-	codePrompt := &survey.Input{
+	err = survey.AskOne(&survey.Input{
 		Message: "invite code?",
-	}
-	err = survey.AskOne(codePrompt, &code,
+	}, &code,
 		survey.WithValidator(survey.Required),
 		survey.WithIcons(surveyIconSet))
 	code = strings.TrimSpace(code)
@@ -45,11 +45,12 @@ func promptCode() (code string, err error) {
 }
 
 func promptUsername(townData stats.TildeData) (un string, err error) {
+	// copied from /etc/adduser.conf
 	usernameRE := regexp.MustCompile(`^[a-z][-a-z0-9_]*$`)
-	unPrompt := &survey.Input{
-		Message: "desired username?",
-	}
-	err = survey.AskOne(unPrompt, &un,
+	err = survey.AskOne(
+		&survey.Input{
+			Message: "desired username?",
+		}, &un,
 		survey.WithValidator(survey.Required),
 		survey.WithIcons(surveyIconSet),
 		survey.WithValidator(func(val interface{}) error {
@@ -82,11 +83,11 @@ func promptUsername(townData stats.TildeData) (un string, err error) {
 }
 
 func promptEmail(defaultEmail string) (email string, err error) {
-	emailPrompt := &survey.Input{
-		Message: "e-mail (for account recovery only)?",
-		Default: defaultEmail,
-	}
-	err = survey.AskOne(emailPrompt, &email,
+	err = survey.AskOne(
+		&survey.Input{
+			Message: "e-mail (for account recovery only)?",
+			Default: defaultEmail,
+		}, &email,
 		survey.WithValidator(survey.Required),
 		survey.WithIcons(surveyIconSet),
 		survey.WithValidator(func(val interface{}) error {
@@ -106,6 +107,30 @@ func promptEmail(defaultEmail string) (email string, err error) {
 	return "", nil
 }
 
+func promptKey() (key string, err error) {
+	err = survey.AskOne(
+		&survey.Input{
+			Message: "SSH public key?",
+		}, &key,
+		survey.WithValidator(survey.Required),
+		survey.WithIcons(surveyIconSet),
+		survey.WithValidator(func(v interface{}) error {
+			key := v.(string)
+			valid, err := sshkey.ValidKey(key)
+			if err != nil {
+				return fmt.Errorf("failed to validate key: %w", err)
+			}
+
+			if !valid {
+				return errors.New("that doesn't seem like a valid SSH key. try another public key?")
+			}
+
+			return nil
+		}))
+
+	return
+}
+
 func _main() error {
 	townData, err := stats.Stats()
 	if err != nil {
@@ -156,7 +181,13 @@ func _main() error {
 		return err
 	}
 
-	// TODO collect public key
+	data.PubKey, err = promptKey()
+	if err != nil {
+		return err
+	}
+
+	// TODO should I allow a review+edit step?
+
 	// TODO have enough to make account; can now do that
 	// TODO assuming account creation succeeded, mark invite as used