From 9c47fafec3be408ba32316145be004a991aa9048 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pavel=20Rosick=C3=BD?= <pavel.rosicky@easy.cz>
Date: Sun, 27 Nov 2022 13:19:26 +0100
Subject: [PATCH 1/2] xoauth2

---
 NEWS.md                    |  5 +++++
 lib/net/smtp.rb            | 30 ++++++++++++++++++++++++++++++
 test/net/smtp/test_smtp.rb | 17 +++++++++++++++++
 3 files changed, 52 insertions(+)

diff --git a/NEWS.md b/NEWS.md
index 0df3239..42ab9df 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,4 +1,9 @@
 # NEWS
+## Unreleased
+
+### Improvements
+
+* Add XOAUTH2 authenticator <https://github.com/ruby/net-smtp/pull/47>
 
 ## Version 0.3.3 (2022-10-29)
 
diff --git a/lib/net/smtp.rb b/lib/net/smtp.rb
index f354708..dd7219e 100644
--- a/lib/net/smtp.rb
+++ b/lib/net/smtp.rb
@@ -857,6 +857,20 @@ def auth_login(user, secret)
       res
     end
 
+    def auth_xoauth2(user, oauth2_token)
+      check_auth_args user, oauth2_token
+
+      auth_string = build_oauth2_string(user, oauth2_token)
+      res = send_xoauth2(base64_encode(auth_string))
+
+      if res.continue?
+        res = get_final_status
+      end
+      
+      check_auth_response res
+      res
+    end
+
     def auth_cram_md5(user, secret)
       check_auth_args user, secret
       res = critical {
@@ -915,6 +929,22 @@ def cram_secret(secret, mask)
       buf
     end
 
+    def send_xoauth2(auth_token)
+      critical {
+        get_response("AUTH XOAUTH2 #{auth_token}")
+      }
+    end
+
+    def build_oauth2_string(user, oauth2_token)
+      "user=%s\1auth=Bearer %s\1\1".encode("us-ascii") % [user, oauth2_token]
+    end
+
+    def get_final_status
+      critical {
+        get_response("")
+      }
+    end
+
     #
     # SMTP command dispatcher
     #
diff --git a/test/net/smtp/test_smtp.rb b/test/net/smtp/test_smtp.rb
index b418b3f..c2ff94d 100644
--- a/test/net/smtp/test_smtp.rb
+++ b/test/net/smtp/test_smtp.rb
@@ -151,6 +151,23 @@ def test_unsucessful_auth_plain
       assert_equal "535", err.response.status
     end
 
+    def test_auth_xoauth2
+      sock = FakeSocket.new("235 2.7.0 Authentication successful\r\n")
+      smtp = Net::SMTP.new 'localhost', 25
+      smtp.instance_variable_set :@socket, sock
+      assert smtp.auth_xoauth2("foo", "bar").success?
+      assert_equal "AUTH XOAUTH2 dXNlcj1mb28BYXV0aD1CZWFyZXIgYmFyAQE=\r\n", sock.write_io.string
+    end
+
+    def test_unsucessful_auth_xoauth2
+      sock = FakeSocket.new("535 5.7.8 BadCredentials\r\n")
+      smtp = Net::SMTP.new 'localhost', 25
+      smtp.instance_variable_set :@socket, sock
+      err = assert_raise(Net::SMTPAuthenticationError) { smtp.auth_xoauth2("foo", "bar") }
+      assert_equal "535 5.7.8 BadCredentials\n", err.message
+      assert_equal "535", err.response.status
+    end
+
     def test_auth_login
       sock = FakeSocket.new("334 VXNlcm5hbWU6\r\n334 UGFzc3dvcmQ6\r\n235 2.7.0 Authentication successful\r\n")
       smtp = Net::SMTP.new 'localhost', 25

From 78e2542a1023e9f060aa18b08cab7909fad49033 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pavel=20Rosick=C3=BD?= <pavel.rosicky@easy.cz>
Date: Thu, 8 Dec 2022 16:55:30 +0100
Subject: [PATCH 2/2] simplify oauth2_string

---
 lib/net/smtp.rb | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/net/smtp.rb b/lib/net/smtp.rb
index dd7219e..13ec53d 100644
--- a/lib/net/smtp.rb
+++ b/lib/net/smtp.rb
@@ -936,7 +936,7 @@ def send_xoauth2(auth_token)
     end
 
     def build_oauth2_string(user, oauth2_token)
-      "user=%s\1auth=Bearer %s\1\1".encode("us-ascii") % [user, oauth2_token]
+      format("user=%s\1auth=Bearer %s\1\1", user, oauth2_token)
     end
 
     def get_final_status