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att.c
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/*
*
* BlueZ - Bluetooth protocol stack for Linux
*
* Copyright (C) 2010 Nokia Corporation
* Copyright (C) 2010 Marcel Holtmann <[email protected]>
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <errno.h>
#include <stdint.h>
#include <stdlib.h>
#include <glib.h>
#include "lib/bluetooth.h"
#include "lib/uuid.h"
#include "src/shared/util.h"
#include "att.h"
static inline void put_uuid_le(const bt_uuid_t *src, void *dst)
{
if (src->type == BT_UUID16)
put_le16(src->value.u16, dst);
else
/* Convert from 128-bit BE to LE */
bswap_128(&src->value.u128, dst);
}
const char *att_ecode2str(uint8_t status)
{
switch (status) {
case ATT_ECODE_INVALID_HANDLE:
return "Invalid handle";
case ATT_ECODE_READ_NOT_PERM:
return "Attribute can't be read";
case ATT_ECODE_WRITE_NOT_PERM:
return "Attribute can't be written";
case ATT_ECODE_INVALID_PDU:
return "Attribute PDU was invalid";
case ATT_ECODE_AUTHENTICATION:
return "Attribute requires authentication before read/write";
case ATT_ECODE_REQ_NOT_SUPP:
return "Server doesn't support the request received";
case ATT_ECODE_INVALID_OFFSET:
return "Offset past the end of the attribute";
case ATT_ECODE_AUTHORIZATION:
return "Attribute requires authorization before read/write";
case ATT_ECODE_PREP_QUEUE_FULL:
return "Too many prepare writes have been queued";
case ATT_ECODE_ATTR_NOT_FOUND:
return "No attribute found within the given range";
case ATT_ECODE_ATTR_NOT_LONG:
return "Attribute can't be read/written using Read Blob Req";
case ATT_ECODE_INSUFF_ENCR_KEY_SIZE:
return "Encryption Key Size is insufficient";
case ATT_ECODE_INVAL_ATTR_VALUE_LEN:
return "Attribute value length is invalid";
case ATT_ECODE_UNLIKELY:
return "Request attribute has encountered an unlikely error";
case ATT_ECODE_INSUFF_ENC:
return "Encryption required before read/write";
case ATT_ECODE_UNSUPP_GRP_TYPE:
return "Attribute type is not a supported grouping attribute";
case ATT_ECODE_INSUFF_RESOURCES:
return "Insufficient Resources to complete the request";
case ATT_ECODE_IO:
return "Internal application error: I/O";
case ATT_ECODE_TIMEOUT:
return "A timeout occured";
case ATT_ECODE_ABORTED:
return "The operation was aborted";
default:
return "Unexpected error code";
}
}
void att_data_list_free(struct att_data_list *list)
{
if (list == NULL)
return;
if (list->data) {
int i;
for (i = 0; i < list->num; i++)
g_free(list->data[i]);
}
g_free(list->data);
g_free(list);
}
struct att_data_list *att_data_list_alloc(uint16_t num, uint16_t len)
{
struct att_data_list *list;
int i;
if (len > UINT8_MAX)
return NULL;
list = g_new0(struct att_data_list, 1);
list->len = len;
list->num = num;
list->data = g_malloc0(sizeof(uint8_t *) * num);
for (i = 0; i < num; i++)
list->data[i] = g_malloc0(sizeof(uint8_t) * len);
return list;
}
static void get_uuid(uint8_t type, const void *val, bt_uuid_t *uuid)
{
if (type == BT_UUID16)
bt_uuid16_create(uuid, get_le16(val));
else {
uint128_t u128;
/* Convert from 128-bit LE to BE */
bswap_128(val, &u128);
bt_uuid128_create(uuid, u128);
}
}
uint16_t enc_read_by_grp_req(uint16_t start, uint16_t end, bt_uuid_t *uuid,
uint8_t *pdu, size_t len)
{
uint16_t uuid_len;
if (!uuid)
return 0;
if (uuid->type == BT_UUID16)
uuid_len = 2;
else if (uuid->type == BT_UUID128)
uuid_len = 16;
else
return 0;
/* Attribute Opcode (1 octet) */
pdu[0] = ATT_OP_READ_BY_GROUP_REQ;
/* Starting Handle (2 octets) */
put_le16(start, &pdu[1]);
/* Ending Handle (2 octets) */
put_le16(end, &pdu[3]);
/* Attribute Group Type (2 or 16 octet UUID) */
put_uuid_le(uuid, &pdu[5]);
return 5 + uuid_len;
}
uint16_t dec_read_by_grp_req(const uint8_t *pdu, size_t len, uint16_t *start,
uint16_t *end, bt_uuid_t *uuid)
{
const size_t min_len = sizeof(pdu[0]) + sizeof(*start) + sizeof(*end);
uint8_t type;
if (pdu == NULL)
return 0;
if (start == NULL || end == NULL || uuid == NULL)
return 0;
if (pdu[0] != ATT_OP_READ_BY_GROUP_REQ)
return 0;
if (len == (min_len + 2))
type = BT_UUID16;
else if (len == (min_len + 16))
type = BT_UUID128;
else
return 0;
*start = get_le16(&pdu[1]);
*end = get_le16(&pdu[3]);
get_uuid(type, &pdu[5], uuid);
return len;
}
uint16_t enc_read_by_grp_resp(struct att_data_list *list, uint8_t *pdu,
size_t len)
{
int i;
uint16_t w;
uint8_t *ptr;
if (list == NULL)
return 0;
if (len < list->len + sizeof(uint8_t) * 2)
return 0;
pdu[0] = ATT_OP_READ_BY_GROUP_RESP;
pdu[1] = list->len;
ptr = &pdu[2];
for (i = 0, w = 2; i < list->num && w + list->len <= len; i++) {
memcpy(ptr, list->data[i], list->len);
ptr += list->len;
w += list->len;
}
return w;
}
struct att_data_list *dec_read_by_grp_resp(const uint8_t *pdu, size_t len)
{
struct att_data_list *list;
const uint8_t *ptr;
uint16_t elen, num;
int i;
if (pdu[0] != ATT_OP_READ_BY_GROUP_RESP)
return NULL;
/* PDU must contain at least:
* - Attribute Opcode (1 octet)
* - Length (1 octet)
* - Attribute Data List (at least one entry):
* - Attribute Handle (2 octets)
* - End Group Handle (2 octets)
* - Attribute Value (at least 1 octet) */
if (len < 7)
return NULL;
elen = pdu[1];
/* Minimum Attribute Data List size */
if (elen < 5)
return NULL;
/* Reject incomplete Attribute Data List */
if ((len - 2) % elen)
return NULL;
num = (len - 2) / elen;
list = att_data_list_alloc(num, elen);
if (list == NULL)
return NULL;
ptr = &pdu[2];
for (i = 0; i < num; i++) {
memcpy(list->data[i], ptr, list->len);
ptr += list->len;
}
return list;
}
uint16_t enc_find_by_type_req(uint16_t start, uint16_t end, bt_uuid_t *uuid,
const uint8_t *value, size_t vlen,
uint8_t *pdu, size_t len)
{
uint16_t min_len = sizeof(pdu[0]) + sizeof(start) + sizeof(end) +
sizeof(uint16_t);
if (pdu == NULL)
return 0;
if (!uuid)
return 0;
if (uuid->type != BT_UUID16)
return 0;
if (vlen > len - min_len)
vlen = len - min_len;
pdu[0] = ATT_OP_FIND_BY_TYPE_REQ;
put_le16(start, &pdu[1]);
put_le16(end, &pdu[3]);
put_le16(uuid->value.u16, &pdu[5]);
if (vlen > 0) {
memcpy(&pdu[7], value, vlen);
return min_len + vlen;
}
return min_len;
}
uint16_t dec_find_by_type_req(const uint8_t *pdu, size_t len, uint16_t *start,
uint16_t *end, bt_uuid_t *uuid,
uint8_t *value, size_t *vlen)
{
if (pdu == NULL)
return 0;
if (len < 7)
return 0;
/* Attribute Opcode (1 octet) */
if (pdu[0] != ATT_OP_FIND_BY_TYPE_REQ)
return 0;
/* First requested handle number (2 octets) */
*start = get_le16(&pdu[1]);
/* Last requested handle number (2 octets) */
*end = get_le16(&pdu[3]);
/* 16-bit UUID to find (2 octets) */
bt_uuid16_create(uuid, get_le16(&pdu[5]));
/* Attribute value to find */
*vlen = len - 7;
if (*vlen > 0)
memcpy(value, pdu + 7, *vlen);
return len;
}
uint16_t enc_find_by_type_resp(GSList *matches, uint8_t *pdu, size_t len)
{
GSList *l;
uint16_t offset;
if (!pdu)
return 0;
pdu[0] = ATT_OP_FIND_BY_TYPE_RESP;
for (l = matches, offset = 1;
l && len >= (offset + sizeof(uint16_t) * 2);
l = l->next, offset += sizeof(uint16_t) * 2) {
struct att_range *range = l->data;
put_le16(range->start, &pdu[offset]);
put_le16(range->end, &pdu[offset + 2]);
}
return offset;
}
GSList *dec_find_by_type_resp(const uint8_t *pdu, size_t len)
{
struct att_range *range;
GSList *matches;
off_t offset;
/* PDU should contain at least:
* - Attribute Opcode (1 octet)
* - Handles Information List (at least one entry):
* - Found Attribute Handle (2 octets)
* - Group End Handle (2 octets) */
if (pdu == NULL || len < 5)
return NULL;
if (pdu[0] != ATT_OP_FIND_BY_TYPE_RESP)
return NULL;
/* Reject incomplete Handles Information List */
if ((len - 1) % 4)
return NULL;
for (offset = 1, matches = NULL;
len >= (offset + sizeof(uint16_t) * 2);
offset += sizeof(uint16_t) * 2) {
range = g_new0(struct att_range, 1);
range->start = get_le16(&pdu[offset]);
range->end = get_le16(&pdu[offset + 2]);
matches = g_slist_append(matches, range);
}
return matches;
}
uint16_t enc_read_by_type_req(uint16_t start, uint16_t end, bt_uuid_t *uuid,
uint8_t *pdu, size_t len)
{
uint16_t uuid_len;
if (!uuid)
return 0;
if (uuid->type == BT_UUID16)
uuid_len = 2;
else if (uuid->type == BT_UUID128)
uuid_len = 16;
else
return 0;
/* Attribute Opcode (1 octet) */
pdu[0] = ATT_OP_READ_BY_TYPE_REQ;
/* Starting Handle (2 octets) */
put_le16(start, &pdu[1]);
/* Ending Handle (2 octets) */
put_le16(end, &pdu[3]);
/* Attribute Type (2 or 16 octet UUID) */
put_uuid_le(uuid, &pdu[5]);
return 5 + uuid_len;
}
uint16_t dec_read_by_type_req(const uint8_t *pdu, size_t len, uint16_t *start,
uint16_t *end, bt_uuid_t *uuid)
{
const size_t min_len = sizeof(pdu[0]) + sizeof(*start) + sizeof(*end);
uint8_t type;
if (pdu == NULL)
return 0;
if (start == NULL || end == NULL || uuid == NULL)
return 0;
if (len == (min_len + 2))
type = BT_UUID16;
else if (len == (min_len + 16))
type = BT_UUID128;
else
return 0;
if (pdu[0] != ATT_OP_READ_BY_TYPE_REQ)
return 0;
*start = get_le16(&pdu[1]);
*end = get_le16(&pdu[3]);
get_uuid(type, &pdu[5], uuid);
return len;
}
uint16_t enc_read_by_type_resp(struct att_data_list *list, uint8_t *pdu,
size_t len)
{
uint8_t *ptr;
size_t i, w, l;
if (list == NULL)
return 0;
if (pdu == NULL)
return 0;
l = MIN(len - 2, list->len);
pdu[0] = ATT_OP_READ_BY_TYPE_RESP;
pdu[1] = l;
ptr = &pdu[2];
for (i = 0, w = 2; i < list->num && w + l <= len; i++) {
memcpy(ptr, list->data[i], l);
ptr += l;
w += l;
}
return w;
}
struct att_data_list *dec_read_by_type_resp(const uint8_t *pdu, size_t len)
{
struct att_data_list *list;
const uint8_t *ptr;
uint16_t elen, num;
int i;
if (pdu[0] != ATT_OP_READ_BY_TYPE_RESP)
return NULL;
/* PDU must contain at least:
* - Attribute Opcode (1 octet)
* - Length (1 octet)
* - Attribute Data List (at least one entry):
* - Attribute Handle (2 octets)
* - Attribute Value (at least 1 octet) */
if (len < 5)
return NULL;
elen = pdu[1];
/* Minimum Attribute Data List size */
if (elen < 3)
return NULL;
/* Reject incomplete Attribute Data List */
if ((len - 2) % elen)
return NULL;
num = (len - 2) / elen;
list = att_data_list_alloc(num, elen);
if (list == NULL)
return NULL;
ptr = &pdu[2];
for (i = 0; i < num; i++) {
memcpy(list->data[i], ptr, list->len);
ptr += list->len;
}
return list;
}
uint16_t enc_write_cmd(uint16_t handle, const uint8_t *value, size_t vlen,
uint8_t *pdu, size_t len)
{
const uint16_t min_len = sizeof(pdu[0]) + sizeof(handle);
if (pdu == NULL)
return 0;
if (vlen > len - min_len)
vlen = len - min_len;
pdu[0] = ATT_OP_WRITE_CMD;
put_le16(handle, &pdu[1]);
if (vlen > 0) {
memcpy(&pdu[3], value, vlen);
return min_len + vlen;
}
return min_len;
}
uint16_t dec_write_cmd(const uint8_t *pdu, size_t len, uint16_t *handle,
uint8_t *value, size_t *vlen)
{
const uint16_t min_len = sizeof(pdu[0]) + sizeof(*handle);
if (pdu == NULL)
return 0;
if (value == NULL || vlen == NULL || handle == NULL)
return 0;
if (len < min_len)
return 0;
if (pdu[0] != ATT_OP_WRITE_CMD)
return 0;
*handle = get_le16(&pdu[1]);
memcpy(value, pdu + min_len, len - min_len);
*vlen = len - min_len;
return len;
}
uint16_t enc_signed_write_cmd(uint16_t handle, const uint8_t *value,
size_t vlen, struct bt_crypto *crypto,
const uint8_t csrk[16],
uint32_t sign_cnt,
uint8_t *pdu, size_t len)
{
const uint16_t hdr_len = sizeof(pdu[0]) + sizeof(handle);
const uint16_t min_len = hdr_len + ATT_SIGNATURE_LEN;
if (pdu == NULL)
return 0;
if (vlen > len - min_len)
vlen = len - min_len;
pdu[0] = ATT_OP_SIGNED_WRITE_CMD;
put_le16(handle, &pdu[1]);
if (vlen > 0)
memcpy(&pdu[hdr_len], value, vlen);
if (!bt_crypto_sign_att(crypto, csrk, pdu, hdr_len + vlen, sign_cnt,
&pdu[hdr_len + vlen]))
return 0;
return min_len + vlen;
}
uint16_t dec_signed_write_cmd(const uint8_t *pdu, size_t len,
uint16_t *handle,
uint8_t *value, size_t *vlen,
uint8_t signature[12])
{
const uint16_t hdr_len = sizeof(pdu[0]) + sizeof(*handle);
const uint16_t min_len = hdr_len + ATT_SIGNATURE_LEN;
if (pdu == NULL)
return 0;
if (value == NULL || vlen == NULL || handle == NULL)
return 0;
if (len < min_len)
return 0;
if (pdu[0] != ATT_OP_SIGNED_WRITE_CMD)
return 0;
*vlen = len - min_len;
*handle = get_le16(&pdu[1]);
memcpy(value, pdu + hdr_len, *vlen);
memcpy(signature, pdu + hdr_len + *vlen, ATT_SIGNATURE_LEN);
return len;
}
uint16_t enc_write_req(uint16_t handle, const uint8_t *value, size_t vlen,
uint8_t *pdu, size_t len)
{
const uint16_t min_len = sizeof(pdu[0]) + sizeof(handle);
if (pdu == NULL)
return 0;
if (vlen > len - min_len)
vlen = len - min_len;
pdu[0] = ATT_OP_WRITE_REQ;
put_le16(handle, &pdu[1]);
if (vlen > 0) {
memcpy(&pdu[3], value, vlen);
return min_len + vlen;
}
return min_len;
}
uint16_t dec_write_req(const uint8_t *pdu, size_t len, uint16_t *handle,
uint8_t *value, size_t *vlen)
{
const uint16_t min_len = sizeof(pdu[0]) + sizeof(*handle);
if (pdu == NULL)
return 0;
if (value == NULL || vlen == NULL || handle == NULL)
return 0;
if (len < min_len)
return 0;
if (pdu[0] != ATT_OP_WRITE_REQ)
return 0;
*handle = get_le16(&pdu[1]);
*vlen = len - min_len;
if (*vlen > 0)
memcpy(value, pdu + min_len, *vlen);
return len;
}
uint16_t enc_write_resp(uint8_t *pdu)
{
if (pdu == NULL)
return 0;
pdu[0] = ATT_OP_WRITE_RESP;
return sizeof(pdu[0]);
}
uint16_t dec_write_resp(const uint8_t *pdu, size_t len)
{
if (pdu == NULL)
return 0;
if (pdu[0] != ATT_OP_WRITE_RESP)
return 0;
return len;
}
uint16_t enc_read_req(uint16_t handle, uint8_t *pdu, size_t len)
{
if (pdu == NULL)
return 0;
/* Attribute Opcode (1 octet) */
pdu[0] = ATT_OP_READ_REQ;
/* Attribute Handle (2 octets) */
put_le16(handle, &pdu[1]);
return 3;
}
uint16_t enc_read_blob_req(uint16_t handle, uint16_t offset, uint8_t *pdu,
size_t len)
{
if (pdu == NULL)
return 0;
/* Attribute Opcode (1 octet) */
pdu[0] = ATT_OP_READ_BLOB_REQ;
/* Attribute Handle (2 octets) */
put_le16(handle, &pdu[1]);
/* Value Offset (2 octets) */
put_le16(offset, &pdu[3]);
return 5;
}
uint16_t dec_read_req(const uint8_t *pdu, size_t len, uint16_t *handle)
{
const uint16_t min_len = sizeof(pdu[0]) + sizeof(*handle);
if (pdu == NULL)
return 0;
if (handle == NULL)
return 0;
if (len < min_len)
return 0;
if (pdu[0] != ATT_OP_READ_REQ)
return 0;
*handle = get_le16(&pdu[1]);
return min_len;
}
uint16_t dec_read_blob_req(const uint8_t *pdu, size_t len, uint16_t *handle,
uint16_t *offset)
{
const uint16_t min_len = sizeof(pdu[0]) + sizeof(*handle) +
sizeof(*offset);
if (pdu == NULL)
return 0;
if (handle == NULL)
return 0;
if (offset == NULL)
return 0;
if (len < min_len)
return 0;
if (pdu[0] != ATT_OP_READ_BLOB_REQ)
return 0;
*handle = get_le16(&pdu[1]);
*offset = get_le16(&pdu[3]);
return min_len;
}
uint16_t enc_read_resp(uint8_t *value, size_t vlen, uint8_t *pdu, size_t len)
{
if (pdu == NULL)
return 0;
/* If the attribute value length is longer than the allowed PDU size,
* send only the octets that fit on the PDU. The remaining octets can
* be requested using the Read Blob Request. */
if (vlen > len - 1)
vlen = len - 1;
pdu[0] = ATT_OP_READ_RESP;
memcpy(pdu + 1, value, vlen);
return vlen + 1;
}
uint16_t enc_read_blob_resp(uint8_t *value, size_t vlen, uint16_t offset,
uint8_t *pdu, size_t len)
{
if (pdu == NULL)
return 0;
vlen -= offset;
if (vlen > len - 1)
vlen = len - 1;
pdu[0] = ATT_OP_READ_BLOB_RESP;
memcpy(pdu + 1, &value[offset], vlen);
return vlen + 1;
}
ssize_t dec_read_resp(const uint8_t *pdu, size_t len, uint8_t *value,
size_t vlen)
{
if (pdu == NULL)
return -EINVAL;
if (pdu[0] != ATT_OP_READ_RESP)
return -EINVAL;
if (value == NULL)
return len - 1;
if (vlen < (len - 1))
return -ENOBUFS;
memcpy(value, pdu + 1, len - 1);
return len - 1;
}
uint16_t enc_error_resp(uint8_t opcode, uint16_t handle, uint8_t status,
uint8_t *pdu, size_t len)
{
/* Attribute Opcode (1 octet) */
pdu[0] = ATT_OP_ERROR;
/* Request Opcode In Error (1 octet) */
pdu[1] = opcode;
/* Attribute Handle In Error (2 octets) */
put_le16(handle, &pdu[2]);
/* Error Code (1 octet) */
pdu[4] = status;
return 5;
}
uint16_t enc_find_info_req(uint16_t start, uint16_t end, uint8_t *pdu,
size_t len)
{
if (pdu == NULL)
return 0;
/* Attribute Opcode (1 octet) */
pdu[0] = ATT_OP_FIND_INFO_REQ;
/* Starting Handle (2 octets) */
put_le16(start, &pdu[1]);
/* Ending Handle (2 octets) */
put_le16(end, &pdu[3]);
return 5;
}
uint16_t dec_find_info_req(const uint8_t *pdu, size_t len, uint16_t *start,
uint16_t *end)
{
const uint16_t min_len = sizeof(pdu[0]) + sizeof(*start) + sizeof(*end);
if (pdu == NULL)
return 0;
if (len < min_len)
return 0;
if (start == NULL || end == NULL)
return 0;
if (pdu[0] != ATT_OP_FIND_INFO_REQ)
return 0;
*start = get_le16(&pdu[1]);
*end = get_le16(&pdu[3]);
return min_len;
}
uint16_t enc_find_info_resp(uint8_t format, struct att_data_list *list,
uint8_t *pdu, size_t len)
{
uint8_t *ptr;
size_t i, w;
if (pdu == NULL)
return 0;
if (list == NULL)
return 0;
if (len < list->len + sizeof(uint8_t) * 2)
return 0;
pdu[0] = ATT_OP_FIND_INFO_RESP;
pdu[1] = format;
ptr = (void *) &pdu[2];
for (i = 0, w = 2; i < list->num && w + list->len <= len; i++) {
memcpy(ptr, list->data[i], list->len);
ptr += list->len;
w += list->len;
}
return w;
}
struct att_data_list *dec_find_info_resp(const uint8_t *pdu, size_t len,
uint8_t *format)
{
struct att_data_list *list;
uint8_t *ptr;
uint16_t elen, num;
int i;
if (pdu == NULL)
return 0;
if (format == NULL)
return 0;
if (pdu[0] != ATT_OP_FIND_INFO_RESP)
return 0;
*format = pdu[1];
elen = sizeof(pdu[0]) + sizeof(*format);
if (*format == 0x01)
elen += 2;
else if (*format == 0x02)
elen += 16;
num = (len - 2) / elen;
ptr = (void *) &pdu[2];
list = att_data_list_alloc(num, elen);
if (list == NULL)
return NULL;
for (i = 0; i < num; i++) {
memcpy(list->data[i], ptr, list->len);
ptr += list->len;
}
return list;
}
uint16_t enc_notification(uint16_t handle, uint8_t *value, size_t vlen,
uint8_t *pdu, size_t len)
{
const uint16_t min_len = sizeof(pdu[0]) + sizeof(uint16_t);
if (pdu == NULL)
return 0;
if (len < (vlen + min_len))
return 0;
pdu[0] = ATT_OP_HANDLE_NOTIFY;
put_le16(handle, &pdu[1]);
memcpy(&pdu[3], value, vlen);
return vlen + min_len;
}
uint16_t enc_indication(uint16_t handle, uint8_t *value, size_t vlen,
uint8_t *pdu, size_t len)
{
const uint16_t min_len = sizeof(pdu[0]) + sizeof(uint16_t);
if (pdu == NULL)
return 0;
if (len < (vlen + min_len))
return 0;
pdu[0] = ATT_OP_HANDLE_IND;
put_le16(handle, &pdu[1]);
memcpy(&pdu[3], value, vlen);
return vlen + min_len;
}
uint16_t dec_indication(const uint8_t *pdu, size_t len, uint16_t *handle,
uint8_t *value, size_t vlen)
{
const uint16_t min_len = sizeof(pdu[0]) + sizeof(uint16_t);
uint16_t dlen;
if (pdu == NULL)
return 0;
if (pdu[0] != ATT_OP_HANDLE_IND)
return 0;
if (len < min_len)
return 0;
dlen = MIN(len - min_len, vlen);
if (handle)
*handle = get_le16(&pdu[1]);
memcpy(value, &pdu[3], dlen);