Bluetooth: eir: Add helpers for managing service data

This adds helpers for accessing and appending service data (0x16) ad
type.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

2 files changed, 35 insertions, 0 deletions

diff --git a/net/bluetooth/eir.c b/net/bluetooth/eir.c
index 7e930f77ecab..7d77fb00c2bf 100644
--- a/net/bluetooth/eir.c
+++ b/net/bluetooth/eir.c
@@ -55,6 +55,19 @@ u8 eir_append_appearance(struct hci_dev *hdev, u8 *ptr, u8 ad_len)
 	return eir_append_le16(ptr, ad_len, EIR_APPEARANCE, hdev->appearance);
 }
 
+u8 eir_append_service_data(u8 *eir, u16 eir_len, u16 uuid, u8 *data,
+			   u8 data_len)
+{
+	eir[eir_len++] = sizeof(u8) + sizeof(uuid) + data_len;
+	eir[eir_len++] = EIR_SERVICE_DATA;
+	put_unaligned_le16(uuid, &eir[eir_len]);
+	eir_len += sizeof(uuid);
+	memcpy(&eir[eir_len], data, data_len);
+	eir_len += data_len;
+
+	return eir_len;
+}
+
 static u8 *create_uuid16_list(struct hci_dev *hdev, u8 *data, ptrdiff_t len)
 {
 	u8 *ptr = data, *uuids_start = NULL;
@@ -333,3 +346,21 @@ u8 eir_create_scan_rsp(struct hci_dev *hdev, u8 instance, u8 *ptr)
 
 	return scan_rsp_len;
 }
+
+void *eir_get_service_data(u8 *eir, size_t eir_len, u16 uuid, size_t *len)
+{
+	while ((eir = eir_get_data(eir, eir_len, EIR_SERVICE_DATA, len))) {
+		u16 value = get_unaligned_le16(eir);
+
+		if (uuid == value) {
+			if (len)
+				*len -= 2;
+			return &eir[2];
+		}
+
+		eir += *len;
+		eir_len -= *len;
+	}
+
+	return NULL;
+}
diff --git a/net/bluetooth/eir.h b/net/bluetooth/eir.h
index 43f1945bffc5..62f2374078f2 100644
--- a/net/bluetooth/eir.h
+++ b/net/bluetooth/eir.h
@@ -14,6 +14,8 @@ u8 eir_create_scan_rsp(struct hci_dev *hdev, u8 instance, u8 *ptr);
 
 u8 eir_append_local_name(struct hci_dev *hdev, u8 *eir, u8 ad_len);
 u8 eir_append_appearance(struct hci_dev *hdev, u8 *ptr, u8 ad_len);
+u8 eir_append_service_data(u8 *eir, u16 eir_len, u16 uuid, u8 *data,
+			   u8 data_len);
 
 static inline u16 eir_precalc_len(u8 data_len)
 {
@@ -92,3 +94,5 @@ static inline void *eir_get_data(u8 *eir, size_t eir_len, u8 type,
 
 	return NULL;
 }
+
+void *eir_get_service_data(u8 *eir, size_t eir_len, u16 uuid, size_t *len);