Settings page for adding verified nostr pubkeys

app/assets/stylesheets/components/base.css

@@ -24,6 +24,10 @@
     @apply text-xl mb-6;
   }
 
+  h4 {
+    @apply font-bold mb-4 leading-6;
+  }
+
   main section {
     @apply pt-8 sm:pt-12;
   }

app/assets/stylesheets/components/buttons.css

@@ -32,4 +32,9 @@
     @apply bg-red-600 hover:bg-red-700 text-white
            focus:ring-red-500 focus:ring-opacity-75;
   }
+
+  .btn:disabled {
+    @apply bg-gray-100 hover:bg-gray-200 text-gray-400
+           focus:ring-gray-300 focus:ring-opacity-75;
+  }
 }

app/assets/stylesheets/components/forms.css

@@ -15,6 +15,10 @@
     @apply border-b-red-600;
   }
 
+  .field_with_errors {
+    @apply inline-block;
+  }
+
   .error-msg {
     @apply text-red-700;
   }

app/controllers/settings_controller.rb

@@ -1,3 +1,5 @@
+require 'securerandom'
+
 class SettingsController < ApplicationController
   before_action :authenticate_user!
   before_action :set_main_nav_section
@@ -9,6 +11,9 @@ class SettingsController < ApplicationController
   end
 
   def show
+    if @settings_section == "experiments"
+      session[:shared_secret] ||= SecureRandom.base64(12)
+    end
   end
 
   def update
@@ -53,6 +58,36 @@ class SettingsController < ApplicationController
     redirect_to check_your_email_path, notice: msg
   end
 
+  def set_nostr_pubkey
+    signed_event = nostr_event_params[:signed_event].to_h.symbolize_keys
+    is_valid_id  = NostrManager::ValidateId.call(signed_event)
+    is_valid_sig = NostrManager::VerifySignature.call(signed_event)
+    is_correct_content = signed_event[:content] == "Connect my public key to #{current_user.address} (confirmation #{session[:shared_secret]})"
+
+    unless is_valid_id && is_valid_sig && is_correct_content
+      flash[:alert] = "Public key could not be verified"
+      http_status :unprocessable_entity and return
+    end
+
+    pubkey_taken = User.all_except(current_user).where(
+      ou: current_user.ou, nostr_pubkey: signed_event[:pubkey]
+    ).any?
+
+    if pubkey_taken
+      flash[:alert] = "Public key already in use for a different account"
+      http_status :unprocessable_entity and return
+    end
+
+    current_user.update! nostr_pubkey: signed_event[:pubkey]
+    session[:shared_secret] = nil
+
+    flash[:success] = "Public key verification successful"
+    http_status :ok
+  rescue
+    flash[:alert] = "Public key could not be verified"
+    http_status :unprocessable_entity and return
+  end
+
   private
 
     def set_main_nav_section
@@ -61,7 +96,7 @@ class SettingsController < ApplicationController
 
     def set_settings_section
       @settings_section = params[:section]
-      allowed_sections = [:profile, :account, :lightning, :xmpp]
+      allowed_sections = [:profile, :account, :lightning, :xmpp, :experiments]
 
       unless allowed_sections.include?(@settings_section.to_sym)
         redirect_to setting_path(:profile)
@@ -82,4 +117,10 @@ class SettingsController < ApplicationController
     def email_params
       params.require(:user).permit(:email, :current_password)
     end
+
+    def nostr_event_params
+      params.permit(signed_event: [
+        :id, :pubkey, :created_at, :kind, :tags, :content, :sig
+      ])
+    end
 end

app/javascript/controllers/settings/nostr_pubkey_controller.js

@@ -0,0 +1,63 @@
+import { Controller } from "@hotwired/stimulus"
+import { bech32 } from "bech32"
+
+function hexToBytes (hex) {
+  let bytes = []
+  for (let c = 0; c < hex.length; c += 2) {
+    bytes.push(parseInt(hex.substr(c, 2), 16))
+  }
+  return bytes
+}
+
+// Connects to data-controller="settings--nostr-pubkey"
+export default class extends Controller {
+  static targets = [ "noExtension", "setPubkey", "pubkeyBech32Input" ]
+  static values  = { userAddress: String, pubkeyHex: String, sharedSecret: String }
+
+  connect () {
+    if (this.hasPubkeyHexValue && this.pubkeyHexValue.length > 0) {
+      this.pubkeyBech32InputTarget.value = this.pubkeyBech32
+    }
+
+    if (window.nostr) {
+      this.setPubkeyTarget.disabled = false
+    } else {
+      this.noExtensionTarget.classList.remove("hidden")
+    }
+  }
+
+  async setPubkey () {
+    this.setPubkeyTarget.disabled = true
+
+    try {
+      const signedEvent = await window.nostr.signEvent({
+        created_at: Math.floor(Date.now() / 1000),
+        kind: 1,
+        tags: [],
+        content: `Connect my public key to ${this.userAddressValue} (confirmation ${this.sharedSecretValue})`
+      })
+
+      const res = await fetch("/settings/set_nostr_pubkey", {
+        method: "POST", credentials: "include", headers: {
+          "Accept": "application/json", 'Content-Type': 'application/json',
+          "X-CSRF-Token": this.csrfToken
+        }, body: JSON.stringify({ signed_event: signedEvent })
+      });
+
+      window.location.reload()
+    } catch (error) {
+      console.warn('Unable to verify pubkey:', error.message)
+      this.setPubkeyTarget.disabled = false
+    }
+  }
+
+  get pubkeyBech32 () {
+    const words = bech32.toWords(hexToBytes(this.pubkeyHexValue))
+    return bech32.encode('npub', words)
+  }
+
+  get csrfToken () {
+    const element = document.head.querySelector('meta[name="csrf-token"]')
+    return element.getAttribute("content")
+  }
+}

app/models/user.rb

@@ -18,7 +18,7 @@ class User < ApplicationRecord
 
   has_many :accounts, through: :lndhub_user
 
-  validates_uniqueness_of :cn
+  validates_uniqueness_of :cn, scope: :ou
   validates_length_of :cn, minimum: 3
   validates_format_of :cn, with: /\A([a-z0-9\-])*\z/,
                            if: Proc.new{ |u| u.cn.present? },
@@ -36,8 +36,11 @@ class User < ApplicationRecord
   validates_length_of :display_name, minimum: 3, maximum: 35, allow_blank: true,
                                      if: -> { defined?(@display_name) }
 
-  scope :confirmed, -> { where.not(confirmed_at: nil) }
-  scope :pending,   -> { where(confirmed_at: nil) }
+  validates_uniqueness_of :nostr_pubkey, scope: :ou, allow_blank: true
+
+  scope :confirmed,  -> { where.not(confirmed_at: nil) }
+  scope :pending,    -> { where(confirmed_at: nil) }
+  scope :all_except, -> (user) { where.not(id: user) }
 
   has_encrypted :ln_login, :ln_password
 

app/services/nostr_manager/validate_id.rb

@@ -0,0 +1,11 @@
+module NostrManager
+  class ValidateId < NostrManagerService
+    def initialize(event)
+      @event = Nostr::Event.new(**event)
+    end
+
+    def call
+      @event.id == Digest::SHA256.hexdigest(JSON.generate(@event.serialize))
+    end
+  end
+end

app/services/nostr_manager/verify_signature.rb

@@ -0,0 +1,17 @@
+module NostrManager
+  class VerifySignature < NostrManagerService
+    def initialize(event)
+      @event = Nostr::Event.new(**event)
+    end
+
+    def call
+      Schnorr.check_sig!(
+        [@event.id].pack('H*'),
+        [@event.pubkey].pack('H*'),
+        [@event.sig].pack('H*')
+      )
+    rescue Schnorr::InvalidSignatureError
+      false
+    end
+  end
+end

app/services/nostr_manager_service.rb

@@ -0,0 +1,4 @@
+require "nostr"
+
+class NostrManagerService < ApplicationService
+end

app/views/icons/_science.html.erb

@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg" height="48" viewBox="0 96 960 960" width="48" class="material-science <%= custom_class %>" fill="currentColor"><path d="M172 936q-41.777 0-59.388-39Q95 858 124 826l248-280V276h-52q-12.75 0-21.375-8.675-8.625-8.676-8.625-21.5 0-12.825 8.625-21.325T320 216h320q12.75 0 21.375 8.675 8.625 8.676 8.625 21.5 0 12.825-8.625 21.325T640 276h-52v270l248 280q29 32 11.388 71-17.611 39-59.388 39H172Zm-12-60h640L528 568V276h-96v292L160 876Zm318-300Z"/></svg>

app/views/settings/_experiments.html.erb

@@ -0,0 +1,62 @@
+<section>
+  <h3>Nostr</h3>
+  <h4 class="mb-0">Public Key</h4>
+  <div data-controller="settings--nostr-pubkey"
+       data-settings--nostr-pubkey-user-address-value="<%= current_user.address %>"
+       data-settings--nostr-pubkey-shared-secret-value="<%= session[:shared_secret] %>"
+       data-settings--nostr-pubkey-pubkey-hex-value="<%= current_user.nostr_pubkey %>">
+
+    <p class="mt-2 <%= current_user.nostr_pubkey.present? ? "" : "hidden" %>">
+      <input type="text" class="w-full" value="<%= current_user.nostr_pubkey %>"
+             data-settings--nostr-pubkey-target="pubkeyBech32Input" disabled />
+    </p>
+
+    <% unless current_user.nostr_pubkey.present? %>
+    <p class="my-4">
+      If you use any apps on the Nostr network, you can verify your public key
+      with us in order to enable Nostr-specific features for your account.
+    </p>
+    <% end %>
+
+    <div data-settings--nostr-pubkey-target="noExtension"
+         class="hidden rounded-md bg-blue-50 p-4">
+      <div class="flex">
+        <div class="flex-shrink-0">
+          <svg class="h-5 w-5 text-blue-400" viewBox="0 0 20 20" fill="currentColor" aria-hidden="true">
+            <path fill-rule="evenodd" d="M18 10a8 8 0 11-16 0 8 8 0 0116 0zm-7-4a1 1 0 11-2 0 1 1 0 012 0zM9 9a.75.75 0 000 1.5h.253a.25.25 0 01.244.304l-.459 2.066A1.75 1.75 0 0010.747 15H11a.75.75 0 000-1.5h-.253a.25.25 0 01-.244-.304l.459-2.066A1.75 1.75 0 009.253 9H9z" clip-rule="evenodd" />
+          </svg>
+        </div>
+        <div class="ml-3">
+          <h3 class="mb-0 text-sm font-bold text-blue-800">
+            No browser extension found
+          </h3>
+          <div class="mt-2 mb-0 text-sm text-blue-800">
+            <p>
+              We recommend Alby, which you can also use for your Lightning
+              Wallet.
+            </p>
+          </div>
+          <div class="mt-4">
+            <div class="-mx-2 -my-1.5 flex">
+              <a href="https://getalby.com" target="_blank"
+                 class="rounded-md bg-blue-50 px-2 py-1.5 text-sm
+                        font-bold text-blue-800 hover:bg-blue-100
+                        focus:outline-none focus:ring-2 focus:ring-blue-600
+                        focus:ring-offset-2 focus:ring-offset-blue-50">
+                Get Alby
+              </a>
+            </div>
+          </div>
+        </div>
+      </div>
+    </div>
+
+    <p class="mt-8">
+      <button class="btn-md btn-gray" disabled
+              data-settings--nostr-pubkey-target="setPubkey"
+              data-action="settings--nostr-pubkey#setPubkey">
+        Get public key from browser extension
+      </button>
+    </p>
+  </div>
+</section>

app/views/shared/_sidenav_settings.html.erb

@@ -18,3 +18,9 @@
   active: @settings_section.to_s == "lightning"
 ) %>
 <% end %>
+<% if Setting.nostr_enabled %>
+<%= render SidenavLinkComponent.new(
+  name: "Experiments", path: setting_path(:experiments), icon: "science",
+  active: @settings_section.to_s == "experiments"
+) %>
+<% end %>