Merge branch 'beta' into dev

esphome/components/sendspin/sendspin_hub.cpp

@@ -107,6 +107,89 @@ std::optional<size_t> parse_record_slot(const std::string &key) {
 
 }  // namespace
 
+namespace {
+
+// The reason passed to on_pairing_failed automations, in the protocol's own spelling.
+StringRef pair_abort_reason_to_string(sendspin::SendspinPairAbortReason reason) {
+  using sendspin::SendspinPairAbortReason;
+  switch (reason) {
+    case SendspinPairAbortReason::ATTEMPT_TIMEOUT:
+      return StringRef::from_lit("attempt_timeout");
+    case SendspinPairAbortReason::CONCURRENT_ATTEMPT:
+      return StringRef::from_lit("concurrent_attempt");
+    case SendspinPairAbortReason::METHOD_NOT_SUPPORTED:
+      return StringRef::from_lit("method_not_supported");
+    case SendspinPairAbortReason::PAIRING_CODE_MISMATCH:
+      return StringRef::from_lit("pairing_code_mismatch");
+    case SendspinPairAbortReason::USER_CANCELLED:
+      return StringRef::from_lit("user_cancelled");
+    case SendspinPairAbortReason::UNKNOWN:
+      break;
+  }
+  return StringRef::from_lit("unknown");
+}
+
+// Zeroes through a volatile pointer so dead-store elimination cannot drop it.
+void secure_wipe(void *data, size_t len) {
+  volatile auto *p = static_cast<volatile uint8_t *>(data);
+  for (size_t i = 0; i < len; ++i) {
+    p[i] = 0;
+  }
+}
+
+// Call once per key, from setup().
+ESPPreferenceObject make_blob_pref(const std::string &name, size_t size) {
+  return global_preferences->make_preference(size, fnv1a_hash("sendspin_" + name));
+}
+
+// Loads straight into the returned buffer, which the library wipes after use. A failed load can
+// leave part of a stored private key or PSK behind, so that path wipes it here. This only covers
+// this buffer: the preference backend keeps its own copy of a pending write until it syncs.
+std::optional<std::vector<uint8_t>> read_blob(ESPPreferenceObject &pref, size_t size) {
+  std::vector<uint8_t> out(size);
+  if (!pref.load(out.data(), out.size())) {
+    secure_wipe(out.data(), out.size());
+    return std::nullopt;
+  }
+  return out;
+}
+
+// The library always writes a key's fixed size; any other length is misuse and is not stored.
+bool write_blob(ESPPreferenceObject &pref, const char *key, size_t size, const uint8_t *data, size_t len) {
+  if (len != size) {
+    ESP_LOGW(TAG, "\"%s\" blob of %zu bytes does not match its size of %zu; rejecting write", key, len, size);
+    return false;
+  }
+  if (!pref.save(data, len)) {
+    ESP_LOGW(TAG, "Failed to persist \"%s\" blob (%zu bytes)", key, len);
+    return false;
+  }
+  return true;
+}
+
+// "rec_<n>" to n; nullopt for any other key or a slot with no storage here.
+std::optional<size_t> parse_record_slot(const std::string &key) {
+  const char *const prefix = sendspin::persistence_keys::RECORD_SLOT_PREFIX;
+  const size_t prefix_len = std::strlen(prefix);
+  if (key.size() <= prefix_len || key.compare(0, prefix_len, prefix) != 0) {
+    return std::nullopt;
+  }
+  size_t slot = 0;
+  for (size_t i = prefix_len; i < key.size(); i++) {
+    const char c = key[i];
+    if (c < '0' || c > '9') {
+      return std::nullopt;
+    }
+    slot = slot * 10 + static_cast<size_t>(c - '0');
+    if (slot >= SENDSPIN_RECORD_SLOTS) {
+      return std::nullopt;
+    }
+  }
+  return slot;
+}
+
+}  // namespace
+
 #ifdef USE_SENDSPIN_ARTWORK
 // Indexed by the library enums, which start at zero and are contiguous.
 static const char *const IMAGE_SOURCE_NAMES[] = {"ALBUM", "ARTIST", "NONE"};