This patch adds bt_att_encode_error_rsp which allows encoding an ATT
protocol error response by correctly converting system errnos to ATT
protocol error codes. struct bt_att_pdu_error_rsp is introduced to
represent an error response PDU which can be sent directly over the
wire once properly encoded in network order.
---
src/shared/att-types.h | 12 ++++
src/shared/att.c | 58 +++++++++++++++++-
src/shared/att.h | 3 +
src/shared/gatt-client.c | 8 ++-
src/shared/gatt-helpers.c | 8 ++-
src/shared/gatt-server.c | 153 +++++++++++++++++++++++-----------------------
6 files changed, 160 insertions(+), 82 deletions(-)
diff --git a/src/shared/att-types.h b/src/shared/att-types.h
index 24bf3da..3d8829a 100644
--- a/src/shared/att-types.h
+++ b/src/shared/att-types.h
@@ -23,6 +23,10 @@
#include <stdint.h>
+#ifndef __packed
+#define __packed __attribute__((packed))
+#endif
+
#define BT_ATT_DEFAULT_LE_MTU 23
/* ATT protocol opcodes */
@@ -55,6 +59,14 @@
#define BT_ATT_OP_HANDLE_VAL_IND 0x1D
#define BT_ATT_OP_HANDLE_VAL_CONF 0x1E
+/* Packed struct definitions for ATT protocol PDUs */
+/* TODO: Complete these definitions for all opcodes */
+struct bt_att_pdu_error_rsp {
+ uint8_t opcode;
+ uint16_t handle;
+ uint8_t ecode;
+} __packed;
+
/* Special opcode to receive all requests (legacy servers) */
#define BT_ATT_ALL_REQUESTS 0x00
diff --git a/src/shared/att.c b/src/shared/att.c
index 6e1e538..e831078 100644
--- a/src/shared/att.c
+++ b/src/shared/att.c
@@ -35,13 +35,22 @@
#include "src/shared/timeout.h"
#include "lib/uuid.h"
#include "src/shared/att.h"
-#include "src/shared/att-types.h"
#define ATT_MIN_PDU_LEN 1 /* At least 1 byte for the opcode. */
#define ATT_OP_CMD_MASK 0x40
#define ATT_OP_SIGNED_MASK 0x80
#define ATT_TIMEOUT_INTERVAL 30000 /* 30000 ms */
+/*
+ * Common Profile and Service Error Code descriptions (see Supplement to the
+ * Bluetooth Core Specification, sections 1.2 and 2). The error codes within
+ * 0xE0-0xFC are reserved for future use. The remaining 3 are defined as the
+ * following:
+ */
+#define BT_ERROR_CCC_IMPROPERLY_CONFIGURED 0xfd
+#define BT_ERROR_ALREADY_IN_PROGRESS 0xfe
+#define BT_ERROR_OUT_OF_RANGE 0xff
+
struct att_send_op;
struct bt_att {
@@ -1218,3 +1227,50 @@ bool bt_att_unregister_all(struct bt_att *att)
return true;
}
+
+static uint8_t att_ecode_from_error(int err)
+{
+ /*
+ * If the error fits in a single byte, treat it as an ATT protocol
+ * error as is. Since "0" is not a valid ATT protocol error code, we map
+ * that to UNLIKELY below.
+ */
+ if (err > 0 && err < UINT8_MAX)
+ return err;
+
+ /*
+ * Since we allow UNIX errnos, map them to appropriate ATT protocol
+ * and "Common Profile and Service" error codes.
+ */
+ switch (err) {
+ case -ENOENT:
+ return BT_ATT_ERROR_INVALID_HANDLE;
+ case -ENOMEM:
+ return BT_ATT_ERROR_INSUFFICIENT_RESOURCES;
+ case -EALREADY:
+ return BT_ERROR_ALREADY_IN_PROGRESS;
+ case -EOVERFLOW:
+ return BT_ERROR_OUT_OF_RANGE;
+ }
+
+ return BT_ATT_ERROR_UNLIKELY;
+}
+
+bool bt_att_encode_error_rsp(uint8_t opcode, uint16_t handle, int error,
+ struct bt_att_pdu_error_rsp *pdu)
+{
+ uint8_t ecode;
+
+ if (!pdu)
+ return false;
+
+ ecode = att_ecode_from_error(error);
+
+ memset(pdu, 0, sizeof(*pdu));
+
+ pdu->opcode = opcode;
+ put_le16(handle, &pdu->handle);
+ pdu->ecode = ecode;
+
+ return true;
+}
diff --git a/src/shared/att.h b/src/shared/att.h
index 1063021..a1a4821 100644
--- a/src/shared/att.h
+++ b/src/shared/att.h
@@ -76,3 +76,6 @@ unsigned int bt_att_register_disconnect(struct bt_att *att,
bool bt_att_unregister_disconnect(struct bt_att *att, unsigned int id);
bool bt_att_unregister_all(struct bt_att *att);
+
+bool bt_att_encode_error_rsp(uint8_t opcode, uint16_t handle, int error,
+ struct bt_att_pdu_error_rsp *pdu);
diff --git a/src/shared/gatt-client.c b/src/shared/gatt-client.c
index 30b271e..1f82048 100644
--- a/src/shared/gatt-client.c
+++ b/src/shared/gatt-client.c
@@ -1285,10 +1285,14 @@ static bool notify_data_write_ccc(struct notify_data *notify_data, bool enable,
static uint8_t process_error(const void *pdu, uint16_t length)
{
- if (!pdu || length != 4)
+ const struct bt_att_pdu_error_rsp *error_pdu;
+
+ if (!pdu || length != sizeof(struct bt_att_pdu_error_rsp))
return 0;
- return ((uint8_t *) pdu)[3];
+ error_pdu = pdu;
+
+ return error_pdu->ecode;
}
static void enable_ccc_callback(uint8_t opcode, const void *pdu,
diff --git a/src/shared/gatt-helpers.c b/src/shared/gatt-helpers.c
index 220d0eb..9c8a3ba 100644
--- a/src/shared/gatt-helpers.c
+++ b/src/shared/gatt-helpers.c
@@ -430,10 +430,14 @@ static void destroy_mtu_op(void *user_data)
static uint8_t process_error(const void *pdu, uint16_t length)
{
- if (!pdu || length != 4)
+ const struct bt_att_pdu_error_rsp *error_pdu;
+
+ if (!pdu || length != sizeof(struct bt_att_pdu_error_rsp))
return 0;
- return ((uint8_t *) pdu)[3];
+ error_pdu = pdu;
+
+ return error_pdu->ecode;
}
static void mtu_cb(uint8_t opcode, const void *pdu, uint16_t length,
diff --git a/src/shared/gatt-server.c b/src/shared/gatt-server.c
index 2ca318a..3262992 100644
--- a/src/shared/gatt-server.c
+++ b/src/shared/gatt-server.c
@@ -22,6 +22,7 @@
*/
#include <sys/uio.h>
+#include <errno.h>
#include "src/shared/att.h"
#include "lib/uuid.h"
@@ -29,7 +30,6 @@
#include "src/shared/gatt-db.h"
#include "src/shared/gatt-server.h"
#include "src/shared/gatt-helpers.h"
-#include "src/shared/att-types.h"
#include "src/shared/util.h"
#ifndef MAX
@@ -133,22 +133,6 @@ static void bt_gatt_server_free(struct bt_gatt_server *server)
free(server);
}
-static uint8_t att_ecode_from_error(int err)
-{
- if (err < 0 || err > UINT8_MAX)
- return 0xff;
-
- return err;
-}
-
-static void encode_error_rsp(uint8_t opcode, uint16_t handle, uint8_t ecode,
- uint8_t pdu[4])
-{
- pdu[0] = opcode;
- pdu[3] = ecode;
- put_le16(handle, pdu + 1);
-}
-
static bool get_uuid_le(const uint8_t *uuid, size_t len, bt_uuid_t *out_uuid)
{
uint128_t u128;
@@ -315,8 +299,9 @@ static void read_by_grp_type_cb(uint8_t opcode, const void *pdu,
error:
rsp_opcode = BT_ATT_OP_ERROR_RSP;
- rsp_len = 4;
- encode_error_rsp(opcode, ehandle, ecode, rsp_pdu);
+ rsp_len = sizeof(struct bt_att_pdu_error_rsp);
+ bt_att_encode_error_rsp(opcode, ehandle, ecode,
+ (struct bt_att_pdu_error_rsp *) rsp_pdu);
done:
queue_destroy(q, NULL);
@@ -355,13 +340,13 @@ static void read_by_type_read_complete_cb(struct gatt_db_attribute *attr,
/* Terminate the operation if there was an error */
if (err) {
- uint8_t pdu[4];
- uint8_t att_ecode = att_ecode_from_error(err);
+ struct bt_att_pdu_error_rsp error_pdu;
- encode_error_rsp(BT_ATT_OP_READ_BY_TYPE_REQ, handle, att_ecode,
- pdu);
- bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, pdu, 4, NULL,
- NULL, NULL);
+ bt_att_encode_error_rsp(BT_ATT_OP_READ_BY_TYPE_REQ, handle, err,
+ &error_pdu);
+ bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, &error_pdu,
+ sizeof(error_pdu),
+ NULL, NULL, NULL);
async_read_op_destroy(op);
return;
}
@@ -437,8 +422,9 @@ static void process_read_by_type(struct async_read_op *op)
error:
ehandle = gatt_db_attribute_get_handle(attr);
rsp_opcode = BT_ATT_OP_ERROR_RSP;
- rsp_len = 4;
- encode_error_rsp(BT_ATT_OP_READ_BY_TYPE_REQ, ehandle, ecode, op->pdu);
+ rsp_len = sizeof(struct bt_att_pdu_error_rsp);
+ bt_att_encode_error_rsp(BT_ATT_OP_READ_BY_TYPE_REQ, ehandle, ecode,
+ (struct bt_att_pdu_error_rsp *) op->pdu);
done:
bt_att_send(server->att, rsp_opcode, op->pdu, rsp_len, NULL,
@@ -452,7 +438,7 @@ static void read_by_type_cb(uint8_t opcode, const void *pdu,
struct bt_gatt_server *server = user_data;
uint16_t start, end;
bt_uuid_t type;
- uint8_t rsp_pdu[4];
+ struct bt_att_pdu_error_rsp error_pdu;
uint16_t ehandle = 0;
uint8_t ecode;
struct queue *q = NULL;
@@ -524,9 +510,10 @@ static void read_by_type_cb(uint8_t opcode, const void *pdu,
return;
error:
- encode_error_rsp(opcode, ehandle, ecode, rsp_pdu);
+ bt_att_encode_error_rsp(opcode, ehandle, ecode, &error_pdu);
queue_destroy(q, NULL);
- bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, rsp_pdu, 4,
+ bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, &error_pdu,
+ sizeof(error_pdu),
NULL, NULL, NULL);
}
@@ -665,8 +652,9 @@ static void find_info_cb(uint8_t opcode, const void *pdu,
error:
rsp_opcode = BT_ATT_OP_ERROR_RSP;
- rsp_len = 4;
- encode_error_rsp(opcode, ehandle, ecode, rsp_pdu);
+ rsp_len = sizeof(struct bt_att_pdu_error_rsp);
+ bt_att_encode_error_rsp(opcode, ehandle, ecode,
+ (struct bt_att_pdu_error_rsp *) rsp_pdu);
done:
queue_destroy(q, NULL);
@@ -697,11 +685,11 @@ static void write_complete_cb(struct gatt_db_attribute *attr, int err,
handle = gatt_db_attribute_get_handle(attr);
if (err) {
- uint8_t rsp_pdu[4];
- uint8_t att_ecode = att_ecode_from_error(err);
+ struct bt_att_pdu_error_rsp error_pdu;
- encode_error_rsp(op->opcode, handle, att_ecode, rsp_pdu);
- bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, rsp_pdu, 4,
+ bt_att_encode_error_rsp(op->opcode, handle, err, &error_pdu);
+ bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, &error_pdu,
+ sizeof(error_pdu),
NULL, NULL, NULL);
} else {
bt_att_send(server->att, BT_ATT_OP_WRITE_RSP, NULL, 0,
@@ -717,7 +705,7 @@ static void write_cb(uint8_t opcode, const void *pdu,
struct bt_gatt_server *server = user_data;
struct gatt_db_attribute *attr;
uint16_t handle = 0;
- uint8_t rsp_pdu[4];
+ struct bt_att_pdu_error_rsp error_pdu;
struct async_write_op *op = NULL;
uint8_t ecode;
uint32_t perm;
@@ -777,8 +765,9 @@ error:
if (opcode == BT_ATT_OP_WRITE_CMD)
return;
- encode_error_rsp(opcode, handle, ecode, rsp_pdu);
- bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, rsp_pdu, 4,
+ bt_att_encode_error_rsp(opcode, handle, ecode, &error_pdu);
+ bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, &error_pdu,
+ sizeof(error_pdu),
NULL, NULL, NULL);
}
@@ -824,12 +813,12 @@ static void read_complete_cb(struct gatt_db_attribute *attr, int err,
handle = gatt_db_attribute_get_handle(attr);
if (err) {
- uint8_t pdu[4];
- uint8_t att_ecode = att_ecode_from_error(err);
+ struct bt_att_pdu_error_rsp error_pdu;
- encode_error_rsp(op->opcode, handle, att_ecode, pdu);
- bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, pdu, 4, NULL,
- NULL, NULL);
+ bt_att_encode_error_rsp(op->opcode, handle, err, &error_pdu);
+ bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, &error_pdu,
+ sizeof(error_pdu),
+ NULL, NULL, NULL);
async_read_op_destroy(op);
return;
}
@@ -846,7 +835,7 @@ static void handle_read_req(struct bt_gatt_server *server, uint8_t opcode,
uint16_t handle,
uint16_t offset)
{
- uint8_t error_pdu[4];
+ struct bt_att_pdu_error_rsp error_pdu;
struct gatt_db_attribute *attr;
uint8_t ecode;
uint32_t perm;
@@ -898,9 +887,10 @@ error:
if (op)
async_read_op_destroy(op);
- encode_error_rsp(opcode, handle, ecode, error_pdu);
- bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, error_pdu, 4, NULL, NULL,
- NULL);
+ bt_att_encode_error_rsp(opcode, handle, ecode, &error_pdu);
+ bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, &error_pdu,
+ sizeof(error_pdu),
+ NULL, NULL, NULL);
}
static void read_cb(uint8_t opcode, const void *pdu,
@@ -910,11 +900,13 @@ static void read_cb(uint8_t opcode, const void *pdu,
uint16_t handle;
if (length != 2) {
- uint8_t pdu[4];
+ struct bt_att_pdu_error_rsp error_pdu;
- encode_error_rsp(opcode, 0, BT_ATT_ERROR_INVALID_PDU, pdu);
- bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, pdu, 4, NULL,
- NULL, NULL);
+ bt_att_encode_error_rsp(opcode, 0, BT_ATT_ERROR_INVALID_PDU,
+ &error_pdu);
+ bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, &error_pdu,
+ sizeof(error_pdu),
+ NULL, NULL, NULL);
return;
}
@@ -930,11 +922,13 @@ static void read_blob_cb(uint8_t opcode, const void *pdu,
uint16_t handle, offset;
if (length != 4) {
- uint8_t pdu[4];
+ struct bt_att_pdu_error_rsp error_pdu;
- encode_error_rsp(opcode, 0, BT_ATT_ERROR_INVALID_PDU, pdu);
- bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, pdu, 4, NULL,
- NULL, NULL);
+ bt_att_encode_error_rsp(opcode, 0, BT_ATT_ERROR_INVALID_PDU,
+ &error_pdu);
+ bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, &error_pdu,
+ sizeof(error_pdu),
+ NULL, NULL, NULL);
return;
}
@@ -1031,8 +1025,9 @@ error:
prep_write_data_destroy(prep_data);
rsp_opcode = BT_ATT_OP_ERROR_RSP;
- rsp_len = 4;
- encode_error_rsp(opcode, handle, ecode, rsp_pdu);
+ rsp_len = sizeof(struct bt_att_pdu_error_rsp);
+ bt_att_encode_error_rsp(opcode, handle, ecode,
+ (struct bt_att_pdu_error_rsp *) rsp_pdu);
done:
bt_att_send(server->att, rsp_opcode, rsp_pdu, rsp_len, NULL, NULL,
@@ -1040,30 +1035,29 @@ done:
}
static void exec_next_prep_write(struct bt_gatt_server *server,
- uint16_t ehandle, uint8_t att_ecode);
+ uint16_t ehandle, int err);
static void exec_write_complete_cb(struct gatt_db_attribute *attr, int err,
void *user_data)
{
struct bt_gatt_server *server = user_data;
uint16_t handle = gatt_db_attribute_get_handle(attr);
- uint16_t att_ecode = att_ecode_from_error(err);
- exec_next_prep_write(server, handle, att_ecode);
+ exec_next_prep_write(server, handle, err);
}
static void exec_next_prep_write(struct bt_gatt_server *server,
- uint16_t ehandle, uint8_t att_ecode)
+ uint16_t ehandle, int err)
{
struct prep_write_data *next = NULL;
uint8_t rsp_opcode = BT_ATT_OP_EXEC_WRITE_RSP;
- uint8_t error_pdu[4];
+ struct bt_att_pdu_error_rsp error_pdu;
uint8_t *rsp_pdu = NULL;
uint16_t rsp_len = 0;
struct gatt_db_attribute *attr;
bool status;
- if (att_ecode)
+ if (err)
goto error;
next = queue_pop_head(server->prep_queue);
@@ -1072,7 +1066,7 @@ static void exec_next_prep_write(struct bt_gatt_server *server,
attr = gatt_db_get_attribute(server->db, next->handle);
if (!attr) {
- att_ecode = BT_ATT_ERROR_UNLIKELY;
+ err = BT_ATT_ERROR_UNLIKELY;
goto error;
}
@@ -1086,14 +1080,15 @@ static void exec_next_prep_write(struct bt_gatt_server *server,
if (status)
return;
- att_ecode = BT_ATT_ERROR_UNLIKELY;
+ err = BT_ATT_ERROR_UNLIKELY;
error:
rsp_opcode = BT_ATT_OP_ERROR_RSP;
- rsp_len = 4;
- rsp_pdu = error_pdu;
- encode_error_rsp(BT_ATT_OP_EXEC_WRITE_REQ, ehandle, att_ecode, rsp_pdu);
+ rsp_len = sizeof(error_pdu);
+ bt_att_encode_error_rsp(BT_ATT_OP_EXEC_WRITE_REQ, ehandle, err,
+ &error_pdu);
+ rsp_pdu = (uint8_t *) &error_pdu;
done:
bt_att_send(server->att, rsp_opcode, rsp_pdu, rsp_len, NULL, NULL,
NULL);
@@ -1106,7 +1101,7 @@ static void exec_write_cb(uint8_t opcode, const void *pdu,
uint8_t flags;
uint8_t ecode;
uint8_t rsp_opcode;
- uint8_t error_pdu[4];
+ struct bt_att_pdu_error_rsp error_pdu;
uint8_t *rsp_pdu = NULL;
uint16_t rsp_len = 0;
bool write;
@@ -1143,9 +1138,10 @@ static void exec_write_cb(uint8_t opcode, const void *pdu,
error:
rsp_opcode = BT_ATT_OP_ERROR_RSP;
- rsp_len = 4;
- rsp_pdu = error_pdu;
- encode_error_rsp(opcode, 0, ecode, rsp_pdu);
+ rsp_len = sizeof(error_pdu);
+ bt_att_encode_error_rsp(opcode, 0, ecode, &error_pdu);
+
+ rsp_pdu = (uint8_t *) &error_pdu;
done:
bt_att_send(server->att, rsp_opcode, rsp_pdu, rsp_len, NULL, NULL,
@@ -1158,12 +1154,15 @@ static void exchange_mtu_cb(uint8_t opcode, const void *pdu,
struct bt_gatt_server *server = user_data;
uint16_t client_rx_mtu;
uint16_t final_mtu;
- uint8_t rsp_pdu[4];
+ uint8_t rsp_pdu[2];
if (length != 2) {
- encode_error_rsp(opcode, 0, BT_ATT_ERROR_INVALID_PDU, rsp_pdu);
- bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, rsp_pdu,
- sizeof(rsp_pdu), NULL, NULL, NULL);
+ struct bt_att_pdu_error_rsp error_pdu;
+
+ bt_att_encode_error_rsp(opcode, 0, BT_ATT_ERROR_INVALID_PDU,
+ &error_pdu);
+ bt_att_send(server->att, BT_ATT_OP_ERROR_RSP, &error_pdu,
+ sizeof(error_pdu), NULL, NULL, NULL);
return;
}
--
2.1.0.rc2.206.gedb03e5
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