From cb97c35d3637c83d1319360f1119ae46c2c730f3 Mon Sep 17 00:00:00 2001
From: Mat931 <49403702+Mat931@users.noreply.github.com>
Date: Fri, 1 May 2026 10:29:41 +0200
Subject: [PATCH] Backport changes

---
 .../components/esphome/ota/ota_esphome.cpp    | 35 ++++++++-----------
 esphome/components/esphome/ota/ota_esphome.h  |  2 --
 2 files changed, 15 insertions(+), 22 deletions(-)

diff --git a/esphome/components/esphome/ota/ota_esphome.cpp b/esphome/components/esphome/ota/ota_esphome.cpp
index 3ae7be7e8f..ca5a382875 100644
--- a/esphome/components/esphome/ota/ota_esphome.cpp
+++ b/esphome/components/esphome/ota/ota_esphome.cpp
@@ -237,19 +237,17 @@ void ESPHomeOTAComponent::handle_handshake_() {
       const bool supports_compression =
           (this->ota_features_ & CLIENT_FEATURE_SUPPORTS_COMPRESSION) != 0 && this->backend_->supports_compression();
 
-      // Compose the feature-ack response. When USE_OTA_PARTITIONS is enabled and the client
-      // negotiates the extended protocol we emit a 2-byte response (marker + server feature flags);
-      // otherwise we emit the single-byte legacy response. The #ifdef wraps only the extended-proto
-      // branch so the legacy branch reads as unconditional code in either build configuration.
-#ifdef USE_OTA_PARTITIONS
+      // Compose the feature-ack response. When the client negotiates the extended protocol we emit
+      // a 2-byte response (marker + server feature flags); otherwise we emit the single-byte
+      // legacy response.
       this->extended_proto_ = (this->ota_features_ & CLIENT_FEATURE_SUPPORTS_EXTENDED_PROTOCOL) != 0;
       if (this->extended_proto_) {
         this->handshake_buf_[0] = ota::OTA_RESPONSE_FEATURE_FLAGS;
-        this->handshake_buf_[1] =
-            SERVER_FEATURE_SUPPORTS_PARTITION_ACCESS | (supports_compression ? SERVER_FEATURE_SUPPORTS_COMPRESSION : 0);
-      } else
+        this->handshake_buf_[1] = (supports_compression ? SERVER_FEATURE_SUPPORTS_COMPRESSION : 0);
+#ifdef USE_OTA_PARTITIONS
+        this->handshake_buf_[1] |= SERVER_FEATURE_SUPPORTS_PARTITION_ACCESS;
 #endif
-      {
+      } else {
         this->handshake_buf_[0] =
             supports_compression ? ota::OTA_RESPONSE_SUPPORTS_COMPRESSION : ota::OTA_RESPONSE_HEADER_OK;
       }
@@ -257,15 +255,12 @@ void ESPHomeOTAComponent::handle_handshake_() {
     }
 
     case OTAState::FEATURE_ACK: {
-#ifdef USE_OTA_PARTITIONS
-      const size_t ack_size = this->extended_proto_ ? 2 : 1;
-#else
-      const size_t ack_size = 1;
-#endif
+      static constexpr size_t STANDARD_PROTO_ACK_SIZE = 1;
+      static constexpr size_t EXTENDED_PROTO_ACK_SIZE = 2;
+      const size_t ack_size = this->extended_proto_ ? EXTENDED_PROTO_ACK_SIZE : STANDARD_PROTO_ACK_SIZE;
       if (!this->try_write_(ack_size, LOG_STR("ack feature"))) {
         return;
       }
-
 #ifdef USE_OTA_PASSWORD
       // If password is set, move to auth phase
       if (!this->password_.empty()) {
@@ -349,9 +344,7 @@ void ESPHomeOTAComponent::handle_data_() {
   uint8_t buf[OTA_BUFFER_SIZE];
   char *sbuf = reinterpret_cast<char *>(buf);
   size_t ota_size;
-#ifdef USE_OTA_PARTITIONS
   ota::OTAType ota_type = ota::OTA_TYPE_UPDATE_APP;
-#endif
 #if USE_OTA_VERSION == 2
   size_t size_acknowledged = 0;
 #endif
@@ -367,7 +360,6 @@ void ESPHomeOTAComponent::handle_data_() {
   // Acknowledge auth OK - 1 byte
   this->write_byte_(ota::OTA_RESPONSE_AUTH_OK);
 
-#ifdef USE_OTA_PARTITIONS
   if (this->extended_proto_) {
     // Read ota type, 1 byte
     if (!this->readall_(buf, 1)) {
@@ -377,7 +369,6 @@ void ESPHomeOTAComponent::handle_data_() {
     ota_type = static_cast<ota::OTAType>(buf[0]);
   }
   ESP_LOGV(TAG, "OTA type is 0x%02x", ota_type);
-#endif
 
   // Read size, 4 bytes MSB first
   if (!this->readall_(buf, 4)) {
@@ -398,10 +389,14 @@ void ESPHomeOTAComponent::handle_data_() {
   this->notify_state_(ota::OTA_STARTED, 0.0f, 0);
 #endif
 
-  // This will block for a few seconds as it locks flash
 #ifdef USE_OTA_PARTITIONS
   error_code = this->backend_->begin(ota_size, ota_type);
 #else
+  if (ota_type != ota::OTA_TYPE_UPDATE_APP) {
+    error_code = ota::OTA_RESPONSE_ERROR_UNSUPPORTED_OTA_TYPE;
+    goto error;  // NOLINT(cppcoreguidelines-avoid-goto)
+  }
+  // This will block for a few seconds as it locks flash
   error_code = this->backend_->begin(ota_size);
 #endif
   if (error_code != ota::OTA_RESPONSE_OK)
diff --git a/esphome/components/esphome/ota/ota_esphome.h b/esphome/components/esphome/ota/ota_esphome.h
index 9bed9240aa..f612451ab0 100644
--- a/esphome/components/esphome/ota/ota_esphome.h
+++ b/esphome/components/esphome/ota/ota_esphome.h
@@ -91,9 +91,7 @@ class ESPHomeOTAComponent final : public ota::OTAComponent {
   std::string password_;
   std::unique_ptr<uint8_t[]> auth_buf_;
 #endif  // USE_OTA_PASSWORD
-#ifdef USE_OTA_PARTITIONS
   bool extended_proto_{false};
-#endif
 
   socket::ListenSocket *server_{nullptr};
   std::unique_ptr<socket::Socket> client_;