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zephyr/subsys/bluetooth/host/sdp.c
Carlos Stuart 75f77db432 include: misc: util.h: Rename min/max to MIN/MAX 
There are issues using lowercase min and max macros when compiling a C++
application with a third-party toolchain such as GNU ARM Embedded when
using some STL headers i.e. <chrono>.

This is because there are actual C++ functions called min and max
defined in some of the STL headers and these macros interfere with them.
By changing the macros to UPPERCASE, which is consistent with almost all
other pre-processor macros this naming conflict is avoided.

All files that use these macros have been updated.

Signed-off-by: Carlos Stuart <carlosstuart1970@gmail.com>
2019-02-14 22:16:03 -05:00

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/** @file
* @brief Service Discovery Protocol handling.
*/
/*
* Copyright (c) 2016 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <errno.h>
#include <sys/types.h>
#include <misc/byteorder.h>
#include <misc/__assert.h>
#include <bluetooth/sdp.h>
#define BT_DBG_ENABLED IS_ENABLED(CONFIG_BT_DEBUG_SDP)
#define LOG_MODULE_NAME bt_sdp
#include "common/log.h"
#include "hci_core.h"
#include "conn_internal.h"
#include "l2cap_internal.h"
#include "sdp_internal.h"
#define SDP_PSM 0x0001
#define SDP_CHAN(_ch) CONTAINER_OF(_ch, struct bt_sdp, chan.chan)
#define IN_RANGE(val, min, max) (val >= min && val <= max)
#define SDP_DATA_MTU 200
#define SDP_MTU (SDP_DATA_MTU + sizeof(struct bt_sdp_hdr))
#define MAX_NUM_ATT_ID_FILTER 10
#define SDP_SERVICE_HANDLE_BASE 0x10000
#define SDP_DATA_ELEM_NEST_LEVEL_MAX 5
/* Size of Cont state length */
#define SDP_CONT_STATE_LEN_SIZE 1
/* 1 byte for the no. of services searched till this response */
/* 2 bytes for the total no. of matching records */
#define SDP_SS_CONT_STATE_SIZE 3
/* 1 byte for the no. of attributes searched till this response */
#define SDP_SA_CONT_STATE_SIZE 1
/* 1 byte for the no. of services searched till this response */
/* 1 byte for the no. of attributes searched till this response */
#define SDP_SSA_CONT_STATE_SIZE 2
#define SDP_INVALID 0xff
struct bt_sdp {
struct bt_l2cap_br_chan chan;
struct k_fifo partial_resp_queue;
/* TODO: Allow more than one pending request */
};
static struct bt_sdp_record *db;
static u8_t num_services;
static struct bt_sdp bt_sdp_pool[CONFIG_BT_MAX_CONN];
/* Pool for outgoing SDP packets */
NET_BUF_POOL_DEFINE(sdp_pool, CONFIG_BT_MAX_CONN,
BT_L2CAP_BUF_SIZE(SDP_MTU), BT_BUF_USER_DATA_MIN, NULL);
#define SDP_CLIENT_CHAN(_ch) CONTAINER_OF(_ch, struct bt_sdp_client, chan.chan)
#define SDP_CLIENT_MTU 64
struct bt_sdp_client {
struct bt_l2cap_br_chan chan;
/* list of waiting to be resolved UUID params */
sys_slist_t reqs;
/* required SDP transaction ID */
u16_t tid;
/* UUID params holder being now resolved */
const struct bt_sdp_discover_params *param;
/* PDU continuation state object */
struct bt_sdp_pdu_cstate cstate;
/* buffer for collecting record data */
struct net_buf *rec_buf;
};
static struct bt_sdp_client bt_sdp_client_pool[CONFIG_BT_MAX_CONN];
enum {
BT_SDP_ITER_STOP,
BT_SDP_ITER_CONTINUE,
};
struct search_state {
u16_t att_list_size;
u8_t current_svc;
u8_t last_att;
bool pkt_full;
};
struct select_attrs_data {
struct bt_sdp_record *rec;
struct net_buf *rsp_buf;
struct bt_sdp *sdp;
struct bt_sdp_data_elem_seq *seq;
struct search_state *state;
u32_t *filter;
u16_t max_att_len;
u16_t att_list_len;
u8_t cont_state_size;
u8_t num_filters;
bool new_service;
};
/* @typedef bt_sdp_attr_func_t
* @brief SDP attribute iterator callback.
*
* @param attr Attribute found.
* @param att_idx Index of the found attribute in the attribute database.
* @param user_data Data given.
*
* @return BT_SDP_ITER_CONTINUE if should continue to the next attribute
* or BT_SDP_ITER_STOP to stop.
*/
typedef u8_t (*bt_sdp_attr_func_t)(struct bt_sdp_attribute *attr,
u8_t att_idx, void *user_data);
/* @typedef bt_sdp_svc_func_t
* @brief SDP service record iterator callback.
*
* @param rec Service record found.
* @param user_data Data given.
*
* @return BT_SDP_ITER_CONTINUE if should continue to the next service record
* or BT_SDP_ITER_STOP to stop.
*/
typedef u8_t (*bt_sdp_svc_func_t)(struct bt_sdp_record *rec,
void *user_data);
/* @brief Callback for SDP connection
*
* Gets called when an SDP connection is established
*
* @param chan L2CAP channel
*
* @return None
*/
static void bt_sdp_connected(struct bt_l2cap_chan *chan)
{
struct bt_l2cap_br_chan *ch = CONTAINER_OF(chan,
struct bt_l2cap_br_chan,
chan);
struct bt_sdp *sdp = CONTAINER_OF(ch, struct bt_sdp, chan);
BT_DBG("chan %p cid 0x%04x", ch, ch->tx.cid);
k_fifo_init(&sdp->partial_resp_queue);
}
/** @brief Callback for SDP disconnection
*
* Gets called when an SDP connection is terminated
*
* @param chan L2CAP channel
*
* @return None
*/
static void bt_sdp_disconnected(struct bt_l2cap_chan *chan)
{
struct bt_l2cap_br_chan *ch = CONTAINER_OF(chan,
struct bt_l2cap_br_chan,
chan);
struct bt_sdp *sdp = CONTAINER_OF(ch, struct bt_sdp, chan);
BT_DBG("chan %p cid 0x%04x", ch, ch->tx.cid);
(void)memset(sdp, 0, sizeof(*sdp));
}
/* @brief Creates an SDP PDU
*
* Creates an empty SDP PDU and returns the buffer
*
* @param None
*
* @return Pointer to the net_buf buffer
*/
static struct net_buf *bt_sdp_create_pdu(void)
{
return bt_l2cap_create_pdu(&sdp_pool, sizeof(struct bt_sdp_hdr));
}
/* @brief Sends out an SDP PDU
*
* Sends out an SDP PDU after adding the relevant header
*
* @param chan L2CAP channel
* @param buf Buffer to be sent out
* @param op Opcode to be used in the packet header
* @param tid Transaction ID to be used in the packet header
*
* @return None
*/
static void bt_sdp_send(struct bt_l2cap_chan *chan, struct net_buf *buf,
u8_t op, u16_t tid)
{
struct bt_sdp_hdr *hdr;
u16_t param_len = buf->len;
hdr = net_buf_push(buf, sizeof(struct bt_sdp_hdr));
hdr->op_code = op;
hdr->tid = tid;
hdr->param_len = sys_cpu_to_be16(param_len);
bt_l2cap_chan_send(chan, buf);
}
/* @brief Sends an error response PDU
*
* Creates and sends an error response PDU
*
* @param chan L2CAP channel
* @param err Error code to be sent in the packet
* @param tid Transaction ID to be used in the packet header
*
* @return None
*/
static void send_err_rsp(struct bt_l2cap_chan *chan, u16_t err,
u16_t tid)
{
struct net_buf *buf;
BT_DBG("tid %u, error %u", tid, err);
buf = bt_sdp_create_pdu();
net_buf_add_be16(buf, err);
bt_sdp_send(chan, buf, BT_SDP_ERROR_RSP, tid);
}
/* @brief Parses data elements from a net_buf
*
* Parses the first data element from a buffer and splits it into type, size,
* data. Used for parsing incoming requests. Net buf is advanced to the data
* part of the element.
*
* @param buf Buffer to be advanced
* @param data_elem Pointer to the parsed data element structure
*
* @return 0 for success, or relevant error code
*/
static u16_t parse_data_elem(struct net_buf *buf,
struct bt_sdp_data_elem *data_elem)
{
u8_t size_field_len = 0U; /* Space used to accommodate the size */
if (buf->len < 1) {
BT_WARN("Malformed packet");
return BT_SDP_INVALID_SYNTAX;
}
data_elem->type = net_buf_pull_u8(buf);
switch (data_elem->type & BT_SDP_TYPE_DESC_MASK) {
case BT_SDP_UINT8:
case BT_SDP_INT8:
case BT_SDP_UUID_UNSPEC:
case BT_SDP_BOOL:
data_elem->data_size = BIT(data_elem->type &
BT_SDP_SIZE_DESC_MASK);
break;
case BT_SDP_TEXT_STR_UNSPEC:
case BT_SDP_SEQ_UNSPEC:
case BT_SDP_ALT_UNSPEC:
case BT_SDP_URL_STR_UNSPEC:
size_field_len = BIT((data_elem->type & BT_SDP_SIZE_DESC_MASK) -
BT_SDP_SIZE_INDEX_OFFSET);
if (buf->len < size_field_len) {
BT_WARN("Malformed packet");
return BT_SDP_INVALID_SYNTAX;
}
switch (size_field_len) {
case 1:
data_elem->data_size = net_buf_pull_u8(buf);
break;
case 2:
data_elem->data_size = net_buf_pull_be16(buf);
break;
case 4:
data_elem->data_size = net_buf_pull_be32(buf);
break;
default:
BT_WARN("Invalid size in remote request");
return BT_SDP_INVALID_SYNTAX;
}
break;
default:
BT_WARN("Invalid type in remote request");
return BT_SDP_INVALID_SYNTAX;
}
if (buf->len < data_elem->data_size) {
BT_WARN("Malformed packet");
return BT_SDP_INVALID_SYNTAX;
}
data_elem->total_size = data_elem->data_size + size_field_len + 1;
data_elem->data = buf->data;
return 0;
}
/* @brief Searches for an UUID within an attribute
*
* Searches for an UUID within an attribute. If the attribute has data element
* sequences, it recursively searches within them as well. On finding a match
* with the UUID, it sets the found flag.
*
* @param elem Attribute to be used as the search space (haystack)
* @param uuid UUID to be looked for (needle)
* @param found Flag set to true if the UUID is found (to be returned)
* @param nest_level Used to limit the extent of recursion into nested data
* elements, to avoid potential stack overflows
*
* @return Size of the last data element that has been searched
* (used in recursion)
*/
static u32_t search_uuid(struct bt_sdp_data_elem *elem, struct bt_uuid *uuid,
bool *found, u8_t nest_level)
{
const u8_t *cur_elem;
u32_t seq_size, size;
union {
struct bt_uuid uuid;
struct bt_uuid_16 u16;
struct bt_uuid_32 u32;
struct bt_uuid_128 u128;
} u;
if (*found) {
return 0;
}
/* Limit recursion depth to avoid stack overflows */
if (nest_level == SDP_DATA_ELEM_NEST_LEVEL_MAX) {
return 0;
}
seq_size = elem->data_size;
cur_elem = elem->data;
if ((elem->type & BT_SDP_TYPE_DESC_MASK) == BT_SDP_UUID_UNSPEC) {
if (seq_size == 2) {
u.uuid.type = BT_UUID_TYPE_16;
u.u16.val = *((u16_t *)cur_elem);
if (!bt_uuid_cmp(&u.uuid, uuid)) {
*found = true;
}
} else if (seq_size == 4) {
u.uuid.type = BT_UUID_TYPE_32;
u.u32.val = *((u32_t *)cur_elem);
if (!bt_uuid_cmp(&u.uuid, uuid)) {
*found = true;
}
} else if (seq_size == 16) {
u.uuid.type = BT_UUID_TYPE_128;
memcpy(u.u128.val, cur_elem, seq_size);
if (!bt_uuid_cmp(&u.uuid, uuid)) {
*found = true;
}
} else {
BT_WARN("Invalid UUID size in local database");
BT_ASSERT(0);
}
}
if ((elem->type & BT_SDP_TYPE_DESC_MASK) == BT_SDP_SEQ_UNSPEC ||
(elem->type & BT_SDP_TYPE_DESC_MASK) == BT_SDP_ALT_UNSPEC) {
do {
/* Recursively parse data elements */
size = search_uuid((struct bt_sdp_data_elem *)cur_elem,
uuid, found, nest_level + 1);
if (*found) {
return 0;
}
cur_elem += sizeof(struct bt_sdp_data_elem);
seq_size -= size;
} while (seq_size);
}
return elem->total_size;
}
/* @brief SDP service record iterator.
*
* Iterate over service records from a starting point.
*
* @param func Callback function.
* @param user_data Data to pass to the callback.
*
* @return Pointer to the record where the iterator stopped, or NULL if all
* records are covered
*/
static struct bt_sdp_record *bt_sdp_foreach_svc(bt_sdp_svc_func_t func,
void *user_data)
{
struct bt_sdp_record *rec = db;
while (rec) {
if (func(rec, user_data) == BT_SDP_ITER_STOP) {
break;
}
rec = rec->next;
}
return rec;
}
/* @brief Inserts a service record into a record pointer list
*
* Inserts a service record into a record pointer list
*
* @param rec The current service record.
* @param user_data Pointer to the destination record list.
*
* @return BT_SDP_ITER_CONTINUE to move on to the next record.
*/
static u8_t insert_record(struct bt_sdp_record *rec, void *user_data)
{
struct bt_sdp_record **rec_list = user_data;
rec_list[rec->index] = rec;
return BT_SDP_ITER_CONTINUE;
}
/* @brief Looks for matching UUIDs in a list of service records
*
* Parses out a sequence of UUIDs from an input buffer, and checks if a record
* in the list contains all the UUIDs. If it doesn't, the record is removed
* from the list, so the list contains only the records which has all the
* input UUIDs in them.
*
* @param buf Incoming buffer containing all the UUIDs to be matched
* @param matching_recs List of service records to use for storing matching
* records
*
* @return 0 for success, or relevant error code
*/
static u16_t find_services(struct net_buf *buf,
struct bt_sdp_record **matching_recs)
{
struct bt_sdp_data_elem data_elem;
struct bt_sdp_record *record;
u32_t uuid_list_size;
u16_t res;
u8_t att_idx, rec_idx = 0U;
bool found;
union {
struct bt_uuid uuid;
struct bt_uuid_16 u16;
struct bt_uuid_32 u32;
struct bt_uuid_128 u128;
} u;
res = parse_data_elem(buf, &data_elem);
if (res) {
return res;
}
if (((data_elem.type & BT_SDP_TYPE_DESC_MASK) != BT_SDP_SEQ_UNSPEC) &&
((data_elem.type & BT_SDP_TYPE_DESC_MASK) != BT_SDP_ALT_UNSPEC)) {
BT_WARN("Invalid type %x in service search pattern",
data_elem.type);
return BT_SDP_INVALID_SYNTAX;
}
uuid_list_size = data_elem.data_size;
bt_sdp_foreach_svc(insert_record, matching_recs);
/* Go over the sequence of UUIDs, and match one UUID at a time */
while (uuid_list_size) {
res = parse_data_elem(buf, &data_elem);
if (res) {
return res;
}
if ((data_elem.type & BT_SDP_TYPE_DESC_MASK) !=
BT_SDP_UUID_UNSPEC) {
BT_WARN("Invalid type %u in service search pattern",
data_elem.type);
return BT_SDP_INVALID_SYNTAX;
}
if (buf->len < data_elem.data_size) {
BT_WARN("Malformed packet");
return BT_SDP_INVALID_SYNTAX;
}
if (data_elem.data_size == 2) {
u.uuid.type = BT_UUID_TYPE_16;
u.u16.val = net_buf_pull_be16(buf);
} else if (data_elem.data_size == 4) {
u.uuid.type = BT_UUID_TYPE_32;
u.u32.val = net_buf_pull_be32(buf);
} else if (data_elem.data_size == 16) {
u.uuid.type = BT_UUID_TYPE_128;
sys_memcpy_swap(u.u128.val, buf->data,
data_elem.data_size);
net_buf_pull(buf, data_elem.data_size);
} else {
BT_WARN("Invalid UUID len %u in service search pattern",
data_elem.data_size);
net_buf_pull(buf, data_elem.data_size);
}
uuid_list_size -= data_elem.total_size;
/* Go over the list of services, and look for a service which
* doesn't have this UUID
*/
for (rec_idx = 0U; rec_idx < num_services; rec_idx++) {
record = matching_recs[rec_idx];
if (!record) {
continue;
}
found = false;
/* Search for the UUID in all the attrs of the svc */
for (att_idx = 0U; att_idx < record->attr_count;
att_idx++) {
search_uuid(&record->attrs[att_idx].val,
&u.uuid, &found, 1);
if (found) {
break;
}
}
/* Remove the record from the list if it doesn't have
* the UUID
*/
if (!found) {
matching_recs[rec_idx] = NULL;
}
}
}
return 0;
}
/* @brief Handler for Service Search Request
*
* Parses, processes and responds to a Service Search Request
*
* @param sdp Pointer to the SDP structure
* @param buf Request net buf
* @param tid Transaction ID
*
* @return 0 for success, or relevant error code
*/
static u16_t sdp_svc_search_req(struct bt_sdp *sdp, struct net_buf *buf,
u16_t tid)
{
struct bt_sdp_svc_rsp *rsp;
struct net_buf *resp_buf;
struct bt_sdp_record *record;
struct bt_sdp_record *matching_recs[BT_SDP_MAX_SERVICES];
u16_t max_rec_count, total_recs = 0U, current_recs = 0U, res;
u8_t cont_state_size, cont_state = 0U, idx = 0U, count = 0U;
bool pkt_full = false;
res = find_services(buf, matching_recs);
if (res) {
/* Error in parsing */
return res;
}
if (buf->len < 3) {
BT_WARN("Malformed packet");
return BT_SDP_INVALID_SYNTAX;
}
max_rec_count = net_buf_pull_be16(buf);
cont_state_size = net_buf_pull_u8(buf);
/* Zero out the matching services beyond max_rec_count */
for (idx = 0U; idx < num_services; idx++) {
if (count == max_rec_count) {
matching_recs[idx] = NULL;
continue;
}
if (matching_recs[idx]) {
count++;
}
}
/* We send out only SDP_SS_CONT_STATE_SIZE bytes continuation state in
* responses, so expect only SDP_SS_CONT_STATE_SIZE bytes in requests
*/
if (cont_state_size) {
if (cont_state_size != SDP_SS_CONT_STATE_SIZE) {
BT_WARN("Invalid cont state size %u", cont_state_size);
return BT_SDP_INVALID_CSTATE;
}
if (buf->len < cont_state_size) {
BT_WARN("Malformed packet");
return BT_SDP_INVALID_SYNTAX;
}
cont_state = net_buf_pull_u8(buf);
/* We include total_recs in the continuation state. We calculate
* it once and preserve it across all the partial responses
*/
total_recs = net_buf_pull_be16(buf);
}
BT_DBG("max_rec_count %u, cont_state %u", max_rec_count, cont_state);
resp_buf = bt_sdp_create_pdu();
rsp = net_buf_add(resp_buf, sizeof(*rsp));
for (; cont_state < num_services; cont_state++) {
record = matching_recs[cont_state];
if (!record) {
continue;
}
/* Calculate total recs only if it is first packet */
if (!cont_state_size) {
total_recs++;
}
if (pkt_full) {
continue;
}
/* 4 bytes per Service Record Handle */
/* 4 bytes for ContinuationState */
if ((MIN(SDP_MTU, sdp->chan.tx.mtu) - resp_buf->len) <
(4 + 4 + sizeof(struct bt_sdp_hdr))) {
pkt_full = true;
}
if (pkt_full) {
/* Packet exhausted: Add continuation state and break */
BT_DBG("Packet full, num_services_covered %u",
cont_state);
net_buf_add_u8(resp_buf, SDP_SS_CONT_STATE_SIZE);
net_buf_add_u8(resp_buf, cont_state);
/* If it is the first packet of a partial response,
* continue dry-running to calculate total_recs.
* Else break
*/
if (cont_state_size) {
break;
}
continue;
}
/* Add the service record handle to the packet */
net_buf_add_be32(resp_buf, record->handle);
current_recs++;
}
/* Add 0 continuation state if packet is exhausted */
if (!pkt_full) {
net_buf_add_u8(resp_buf, 0);
} else {
net_buf_add_be16(resp_buf, total_recs);
}
rsp->total_recs = sys_cpu_to_be16(total_recs);
rsp->current_recs = sys_cpu_to_be16(current_recs);
BT_DBG("Sending response, len %u", resp_buf->len);
bt_sdp_send(&sdp->chan.chan, resp_buf, BT_SDP_SVC_SEARCH_RSP, tid);
return 0;
}
/* @brief Copies an attribute into an outgoing buffer
*
* Copies an attribute into a buffer. Recursively calls itself for complex
* attributes.
*
* @param elem Attribute to be copied to the buffer
* @param buf Buffer where the attribute is to be copied
*
* @return Size of the last data element that has been searched
* (used in recursion)
*/
static u32_t copy_attribute(struct bt_sdp_data_elem *elem,
struct net_buf *buf, u8_t nest_level)
{
const u8_t *cur_elem;
u32_t size, seq_size, total_size;
/* Limit recursion depth to avoid stack overflows */
if (nest_level == SDP_DATA_ELEM_NEST_LEVEL_MAX) {
return 0;
}
seq_size = elem->data_size;
total_size = elem->total_size;
cur_elem = elem->data;
/* Copy the header */
net_buf_add_u8(buf, elem->type);
switch (total_size - (seq_size + 1)) {
case 1:
net_buf_add_u8(buf, elem->data_size);
break;
case 2:
net_buf_add_be16(buf, elem->data_size);
break;
case 4:
net_buf_add_be32(buf, elem->data_size);
break;
}
/* Recursively parse (till the last element is not another data element)
* and then fill the elements
*/
if ((elem->type & BT_SDP_TYPE_DESC_MASK) == BT_SDP_SEQ_UNSPEC ||
(elem->type & BT_SDP_TYPE_DESC_MASK) == BT_SDP_ALT_UNSPEC) {
do {
size = copy_attribute((struct bt_sdp_data_elem *)
cur_elem, buf, nest_level + 1);
cur_elem += sizeof(struct bt_sdp_data_elem);
seq_size -= size;
} while (seq_size);
} else if ((elem->type & BT_SDP_TYPE_DESC_MASK) == BT_SDP_UINT8 ||
(elem->type & BT_SDP_TYPE_DESC_MASK) == BT_SDP_INT8 ||
(elem->type & BT_SDP_TYPE_DESC_MASK) == BT_SDP_UUID_UNSPEC) {
if (seq_size == 1) {
net_buf_add_u8(buf, *((u8_t *)elem->data));
} else if (seq_size == 2) {
net_buf_add_be16(buf, *((u16_t *)elem->data));
} else if (seq_size == 4) {
net_buf_add_be32(buf, *((u32_t *)elem->data));
} else {
/* TODO: Convert 32bit and 128bit values to big-endian*/
net_buf_add_mem(buf, elem->data, seq_size);
}
} else {
net_buf_add_mem(buf, elem->data, seq_size);
}
return total_size;
}
/* @brief SDP attribute iterator.
*
* Iterate over attributes of a service record from a starting index.
*
* @param record Service record whose attributes are to be iterated over.
* @param idx Index in the attribute list from where to start.
* @param func Callback function.
* @param user_data Data to pass to the callback.
*
* @return Index of the attribute where the iterator stopped
*/
static u8_t bt_sdp_foreach_attr(struct bt_sdp_record *record, u8_t idx,
bt_sdp_attr_func_t func, void *user_data)
{
for (; idx < record->attr_count; idx++) {
if (func(&record->attrs[idx], idx, user_data) ==
BT_SDP_ITER_STOP) {
break;
}
}
return idx;
}
/* @brief Check if an attribute matches a range, and include it in the response
*
* Checks if an attribute matches a given attribute ID or range, and if so,
* includes it in the response packet
*
* @param attr The current attribute
* @param att_idx Index of the current attribute in the database
* @param user_data Pointer to the structure containing response packet, byte
* count, states, etc
*
* @return BT_SDP_ITER_CONTINUE if should continue to the next attribute
* or BT_SDP_ITER_STOP to stop.
*/
static u8_t select_attrs(struct bt_sdp_attribute *attr, u8_t att_idx,
void *user_data)
{
struct select_attrs_data *sad = user_data;
u16_t att_id_lower, att_id_upper, att_id_cur, space;
u32_t attr_size, seq_size;
u8_t idx_filter;
for (idx_filter = 0U; idx_filter < sad->num_filters; idx_filter++) {
att_id_lower = (sad->filter[idx_filter] >> 16);
att_id_upper = (sad->filter[idx_filter]);
att_id_cur = attr->id;
/* Check for range values */
if (att_id_lower != 0xffff &&
(!IN_RANGE(att_id_cur, att_id_lower, att_id_upper))) {
continue;
}
/* Check for match values */
if (att_id_lower == 0xffff && att_id_cur != att_id_upper) {
continue;
}
/* Attribute ID matches */
/* 3 bytes for Attribute ID */
attr_size = 3 + attr->val.total_size;
/* If this is the first attribute of the service, then we need
* to account for the space required to add the per-service
* data element sequence header as well.
*/
if ((sad->state->current_svc != sad->rec->index) &&
sad->new_service) {
/* 3 bytes for Per-Service Data Elem Seq declaration */
seq_size = attr_size + 3;
} else {
seq_size = attr_size;
}
if (sad->rsp_buf) {
space = MIN(SDP_MTU, sad->sdp->chan.tx.mtu) -
sad->rsp_buf->len - sizeof(struct bt_sdp_hdr);
if ((!sad->state->pkt_full) &&
((seq_size > sad->max_att_len) ||
(space < seq_size + sad->cont_state_size))) {
/* Packet exhausted */
sad->state->pkt_full = true;
}
}
/* Keep filling data only if packet is not exhausted */
if (!sad->state->pkt_full && sad->rsp_buf) {
/* Add Per-Service Data Element Seq declaration once
* only when we are starting from the first attribute
*/
if (!sad->seq &&
(sad->state->current_svc != sad->rec->index)) {
sad->seq = net_buf_add(sad->rsp_buf,
sizeof(*sad->seq));
sad->seq->type = BT_SDP_SEQ16;
sad->seq->size = 0U;
}
/* Add attribute ID */
net_buf_add_u8(sad->rsp_buf, BT_SDP_UINT16);
net_buf_add_be16(sad->rsp_buf, att_id_cur);
/* Add attribute value */
copy_attribute(&attr->val, sad->rsp_buf, 1);
sad->max_att_len -= seq_size;
sad->att_list_len += seq_size;
sad->state->last_att = att_idx;
sad->state->current_svc = sad->rec->index;
}
if (sad->seq) {
/* Keep adding the sequence size if this packet contains
* the Per-Service Data Element Seq declaration header
*/
sad->seq->size += attr_size;
sad->state->att_list_size += seq_size;
} else {
/* Keep adding the total attr lists size if:
* It's a dry-run, calculating the total attr lists size
*/
sad->state->att_list_size += seq_size;
}
sad->new_service = false;
break;
}
/* End the search if:
* 1. We have exhausted the packet
* AND
* 2. This packet doesn't contain the service element declaration header
* AND
* 3. This is not a dry-run (then we look for other attrs that match)
*/
if (sad->state->pkt_full && !sad->seq && sad->rsp_buf) {
return BT_SDP_ITER_STOP;
}
return BT_SDP_ITER_CONTINUE;
}
/* @brief Creates attribute list in the given buffer
*
* Populates the attribute list of a service record in the buffer. To be used
* for responding to Service Attribute and Service Search Attribute requests
*
* @param sdp Pointer to the SDP structure
* @param record Service record whose attributes are to be included in the
* response
* @param filter Attribute values/ranges to be used as a filter
* @param num_filters Number of elements in the attribute filter
* @param max_att_len Maximum size of attributes to be included in the response
* @param cont_state_size No. of additional continuation state bytes to keep
* space for in the packet. This will vary based on the type of the request
* @param next_att Starting position of the search in the service's attr list
* @param state State of the overall search
* @param rsp_buf Response buffer which is filled in
*
* @return len Length of the attribute list created
*/
static u16_t create_attr_list(struct bt_sdp *sdp, struct bt_sdp_record *record,
u32_t *filter, u8_t num_filters,
u16_t max_att_len, u8_t cont_state_size,
u8_t next_att, struct search_state *state,
struct net_buf *rsp_buf)
{
struct select_attrs_data sad;
u8_t idx_att;
sad.num_filters = num_filters;
sad.rec = record;
sad.rsp_buf = rsp_buf;
sad.sdp = sdp;
sad.max_att_len = max_att_len;
sad.cont_state_size = cont_state_size;
sad.seq = NULL;
sad.filter = filter;
sad.state = state;
sad.att_list_len = 0U;
sad.new_service = true;
idx_att = bt_sdp_foreach_attr(sad.rec, next_att, select_attrs, &sad);
if (sad.seq) {
sad.seq->size = sys_cpu_to_be16(sad.seq->size);
}
return sad.att_list_len;
}
/* @brief Extracts the attribute search list from a buffer
*
* Parses a buffer to extract the attribute search list (list of attribute IDs
* and ranges) which are to be used to filter attributes.
*
* @param buf Buffer to be parsed for extracting the attribute search list
* @param filter Empty list of 4byte filters that are filled in. For attribute
* IDs, the lower 2 bytes contain the ID and the upper 2 bytes are set to
* 0xFFFF. For attribute ranges, the lower 2bytes indicate the start ID and
* the upper 2bytes indicate the end ID
* @param num_filters No. of filter elements filled in (to be returned)
*
* @return 0 for success, or relevant error code
*/
static u16_t get_att_search_list(struct net_buf *buf, u32_t *filter,
u8_t *num_filters)
{
struct bt_sdp_data_elem data_elem;
u16_t res;
u32_t size;
*num_filters = 0U;
res = parse_data_elem(buf, &data_elem);
if (res) {
return res;
}
size = data_elem.data_size;
while (size) {
res = parse_data_elem(buf, &data_elem);
if (res) {
return res;
}
if ((data_elem.type & BT_SDP_TYPE_DESC_MASK) != BT_SDP_UINT8) {
BT_WARN("Invalid type %u in attribute ID list",
data_elem.type);
return BT_SDP_INVALID_SYNTAX;
}
if (buf->len < data_elem.data_size) {
BT_WARN("Malformed packet");
return BT_SDP_INVALID_SYNTAX;
}
/* This is an attribute ID */
if (data_elem.data_size == 2) {
filter[(*num_filters)++] = 0xffff0000 |
net_buf_pull_be16(buf);
}
/* This is an attribute ID range */
if (data_elem.data_size == 4) {
filter[(*num_filters)++] = net_buf_pull_be32(buf);
}
size -= data_elem.total_size;
}
return 0;
}
/* @brief Check if a given handle matches that of the current service
*
* Checks if a given handle matches that of the current service
*
* @param rec The current service record
* @param user_data Pointer to the service record handle to be matched
*
* @return BT_SDP_ITER_CONTINUE if should continue to the next record
* or BT_SDP_ITER_STOP to stop.
*/
static u8_t find_handle(struct bt_sdp_record *rec, void *user_data)
{
u32_t *svc_rec_hdl = user_data;
if (rec->handle == *svc_rec_hdl) {
return BT_SDP_ITER_STOP;
}
return BT_SDP_ITER_CONTINUE;
}
/* @brief Handler for Service Attribute Request
*
* Parses, processes and responds to a Service Attribute Request
*
* @param sdp Pointer to the SDP structure
* @param buf Request buffer
* @param tid Transaction ID
*
* @return 0 for success, or relevant error code
*/
static u16_t sdp_svc_att_req(struct bt_sdp *sdp, struct net_buf *buf,
u16_t tid)
{
u32_t filter[MAX_NUM_ATT_ID_FILTER];
struct search_state state = {
.current_svc = SDP_INVALID,
.last_att = SDP_INVALID,
.pkt_full = false
};
struct bt_sdp_record *record;
struct bt_sdp_att_rsp *rsp;
struct net_buf *rsp_buf;
u32_t svc_rec_hdl;
u16_t max_att_len, res, att_list_len;
u8_t num_filters, cont_state_size, next_att = 0U;
if (buf->len < 6) {
BT_WARN("Malformed packet");
return BT_SDP_INVALID_SYNTAX;
}
svc_rec_hdl = net_buf_pull_be32(buf);
max_att_len = net_buf_pull_be16(buf);
/* Set up the filters */
res = get_att_search_list(buf, filter, &num_filters);
if (res) {
/* Error in parsing */
return res;
}
if (buf->len < 1) {
BT_WARN("Malformed packet");
return BT_SDP_INVALID_SYNTAX;
}
cont_state_size = net_buf_pull_u8(buf);
/* We only send out 1 byte continuation state in responses,
* so expect only 1 byte in requests
*/
if (cont_state_size) {
if (cont_state_size != SDP_SA_CONT_STATE_SIZE) {
BT_WARN("Invalid cont state size %u", cont_state_size);
return BT_SDP_INVALID_CSTATE;
}
if (buf->len < cont_state_size) {
BT_WARN("Malformed packet");
return BT_SDP_INVALID_SYNTAX;
}
state.last_att = net_buf_pull_u8(buf) + 1;
next_att = state.last_att;
}
BT_DBG("svc_rec_hdl %u, max_att_len 0x%04x, cont_state %u", svc_rec_hdl,
max_att_len, next_att);
/* Find the service */
record = bt_sdp_foreach_svc(find_handle, &svc_rec_hdl);
if (!record) {
BT_WARN("Handle %u not found", svc_rec_hdl);
return BT_SDP_INVALID_RECORD_HANDLE;
}
/* For partial responses, restore the search state */
if (cont_state_size) {
state.current_svc = record->index;
}
rsp_buf = bt_sdp_create_pdu();
rsp = net_buf_add(rsp_buf, sizeof(*rsp));
/* cont_state_size should include 1 byte header */
att_list_len = create_attr_list(sdp, record, filter, num_filters,
max_att_len, SDP_SA_CONT_STATE_SIZE + 1,
next_att, &state, rsp_buf);
if (!att_list_len) {
/* For empty responses, add an empty data element sequence */
net_buf_add_u8(rsp_buf, BT_SDP_SEQ8);
net_buf_add_u8(rsp_buf, 0);
att_list_len = 2U;
}
/* Add continuation state */
if (state.pkt_full) {
BT_DBG("Packet full, state.last_att %u", state.last_att);
net_buf_add_u8(rsp_buf, 1);
net_buf_add_u8(rsp_buf, state.last_att);
} else {
net_buf_add_u8(rsp_buf, 0);
}
rsp->att_list_len = sys_cpu_to_be16(att_list_len);
BT_DBG("Sending response, len %u", rsp_buf->len);
bt_sdp_send(&sdp->chan.chan, rsp_buf, BT_SDP_SVC_ATTR_RSP, tid);
return 0;
}
/* @brief Handler for Service Search Attribute Request
*
* Parses, processes and responds to a Service Search Attribute Request
*
* @param sdp Pointer to the SDP structure
* @param buf Request buffer
* @param tid Transaction ID
*
* @return 0 for success, or relevant error code
*/
static u16_t sdp_svc_search_att_req(struct bt_sdp *sdp, struct net_buf *buf,
u16_t tid)
{
u32_t filter[MAX_NUM_ATT_ID_FILTER];
struct bt_sdp_record *matching_recs[BT_SDP_MAX_SERVICES];
struct search_state state = {
.att_list_size = 0,
.current_svc = SDP_INVALID,
.last_att = SDP_INVALID,
.pkt_full = false
};
struct net_buf *rsp_buf, *rsp_buf_cpy;
struct bt_sdp_record *record;
struct bt_sdp_att_rsp *rsp;
struct bt_sdp_data_elem_seq *seq = NULL;
u16_t max_att_len, res, att_list_len = 0U;
u8_t num_filters, cont_state_size, next_svc = 0U, next_att = 0U;
bool dry_run = false;
res = find_services(buf, matching_recs);
if (res) {
return res;
}
if (buf->len < 2) {
BT_WARN("Malformed packet");
return BT_SDP_INVALID_SYNTAX;
}
max_att_len = net_buf_pull_be16(buf);
/* Set up the filters */
res = get_att_search_list(buf, filter, &num_filters);
if (res) {
/* Error in parsing */
return res;
}
if (buf->len < 1) {
BT_WARN("Malformed packet");
return BT_SDP_INVALID_SYNTAX;
}
cont_state_size = net_buf_pull_u8(buf);
/* We only send out 2 bytes continuation state in responses,
* so expect only 2 bytes in requests
*/
if (cont_state_size) {
if (cont_state_size != SDP_SSA_CONT_STATE_SIZE) {
BT_WARN("Invalid cont state size %u", cont_state_size);
return BT_SDP_INVALID_CSTATE;
}
if (buf->len < cont_state_size) {
BT_WARN("Malformed packet");
return BT_SDP_INVALID_SYNTAX;
}
state.current_svc = net_buf_pull_u8(buf);
state.last_att = net_buf_pull_u8(buf) + 1;
next_svc = state.current_svc;
next_att = state.last_att;
}
BT_DBG("max_att_len 0x%04x, state.current_svc %u, state.last_att %u",
max_att_len, state.current_svc, state.last_att);
rsp_buf = bt_sdp_create_pdu();
rsp = net_buf_add(rsp_buf, sizeof(*rsp));
/* Add headers only if this is not a partial response */
if (!cont_state_size) {
seq = net_buf_add(rsp_buf, sizeof(*seq));
seq->type = BT_SDP_SEQ16;
seq->size = 0U;
/* 3 bytes for Outer Data Element Sequence declaration */
att_list_len = 3U;
}
rsp_buf_cpy = rsp_buf;
for (; next_svc < num_services; next_svc++) {
record = matching_recs[next_svc];
if (!record) {
continue;
}
att_list_len += create_attr_list(sdp, record, filter,
num_filters, max_att_len,
SDP_SSA_CONT_STATE_SIZE + 1,
next_att, &state, rsp_buf_cpy);
/* Check if packet is full and not dry run */
if (state.pkt_full && !dry_run) {
BT_DBG("Packet full, state.last_att %u",
state.last_att);
dry_run = true;
/* Add continuation state */
net_buf_add_u8(rsp_buf, 2);
net_buf_add_u8(rsp_buf, state.current_svc);
net_buf_add_u8(rsp_buf, state.last_att);
/* Break if it's not a partial response, else dry-run
* Dry run: Look for other services that match
*/
if (cont_state_size) {
break;
}
rsp_buf_cpy = NULL;
}
next_att = 0U;
}
if (!dry_run) {
if (!att_list_len) {
/* For empty responses, add an empty data elem seq */
net_buf_add_u8(rsp_buf, BT_SDP_SEQ8);
net_buf_add_u8(rsp_buf, 0);
att_list_len = 2U;
}
/* Search exhausted */
net_buf_add_u8(rsp_buf, 0);
}
rsp->att_list_len = sys_cpu_to_be16(att_list_len);
if (seq) {
seq->size = sys_cpu_to_be16(state.att_list_size);
}
BT_DBG("Sending response, len %u", rsp_buf->len);
bt_sdp_send(&sdp->chan.chan, rsp_buf, BT_SDP_SVC_SEARCH_ATTR_RSP,
tid);
return 0;
}
static const struct {
u8_t op_code;
u16_t (*func)(struct bt_sdp *sdp, struct net_buf *buf, u16_t tid);
} handlers[] = {
{ BT_SDP_SVC_SEARCH_REQ, sdp_svc_search_req },
{ BT_SDP_SVC_ATTR_REQ, sdp_svc_att_req },
{ BT_SDP_SVC_SEARCH_ATTR_REQ, sdp_svc_search_att_req },
};
/* @brief Callback for SDP data receive
*
* Gets called when an SDP PDU is received. Calls the corresponding handler
* based on the op code of the PDU.
*
* @param chan L2CAP channel
* @param buf Received PDU
*
* @return None
*/
static int bt_sdp_recv(struct bt_l2cap_chan *chan, struct net_buf *buf)
{
struct bt_l2cap_br_chan *ch = CONTAINER_OF(chan,
struct bt_l2cap_br_chan, chan);
struct bt_sdp *sdp = CONTAINER_OF(ch, struct bt_sdp, chan);
struct bt_sdp_hdr *hdr;
u16_t err = BT_SDP_INVALID_SYNTAX;
size_t i;
BT_DBG("chan %p, ch %p, cid 0x%04x", chan, ch, ch->tx.cid);
BT_ASSERT(sdp);
if (buf->len < sizeof(*hdr)) {
BT_ERR("Too small SDP PDU received");
return 0;
}
hdr = net_buf_pull_mem(buf, sizeof(*hdr));
BT_DBG("Received SDP code 0x%02x len %u", hdr->op_code, buf->len);
if (sys_cpu_to_be16(hdr->param_len) != buf->len) {
err = BT_SDP_INVALID_PDU_SIZE;
} else {
for (i = 0; i < ARRAY_SIZE(handlers); i++) {
if (hdr->op_code != handlers[i].op_code) {
continue;
}
err = handlers[i].func(sdp, buf, hdr->tid);
break;
}
}
if (err) {
BT_WARN("SDP error 0x%02x", err);
send_err_rsp(chan, err, hdr->tid);
}
return 0;
}
/* @brief Callback for SDP connection accept
*
* Gets called when an incoming SDP connection needs to be authorized.
* Registers the L2CAP callbacks and allocates an SDP context to the connection
*
* @param conn BT connection object
* @param chan L2CAP channel structure (to be returned)
*
* @return 0 for success, or relevant error code
*/
static int bt_sdp_accept(struct bt_conn *conn, struct bt_l2cap_chan **chan)
{
static struct bt_l2cap_chan_ops ops = {
.connected = bt_sdp_connected,
.disconnected = bt_sdp_disconnected,
.recv = bt_sdp_recv,
};
int i;
BT_DBG("conn %p", conn);
for (i = 0; i < ARRAY_SIZE(bt_sdp_pool); i++) {
struct bt_sdp *sdp = &bt_sdp_pool[i];
if (sdp->chan.chan.conn) {
continue;
}
sdp->chan.chan.ops = &ops;
sdp->chan.rx.mtu = SDP_MTU;
*chan = &sdp->chan.chan;
return 0;
}
BT_ERR("No available SDP context for conn %p", conn);
return -ENOMEM;
}
void bt_sdp_init(void)
{
static struct bt_l2cap_server server = {
.psm = SDP_PSM,
.accept = bt_sdp_accept,
.sec_level = BT_SECURITY_NONE,
};
int res;
res = bt_l2cap_br_server_register(&server);
if (res) {
BT_ERR("L2CAP server registration failed with error %d", res);
}
}
int bt_sdp_register_service(struct bt_sdp_record *service)
{
u32_t handle = SDP_SERVICE_HANDLE_BASE;
if (!service) {
BT_ERR("No service record specified");
return 0;
}
if (num_services == BT_SDP_MAX_SERVICES) {
BT_ERR("Reached max allowed registrations");
return -ENOMEM;
}
if (db) {
handle = db->handle + 1;
}
service->next = db;
service->index = num_services++;
service->handle = handle;
*((u32_t *)(service->attrs[0].val.data)) = handle;
db = service;
BT_DBG("Service registered at %u", handle);
return 0;
}
#define GET_PARAM(__node) \
CONTAINER_OF(__node, struct bt_sdp_discover_params, _node)
/* ServiceSearchAttribute PDU, ref to BT Core 4.2, Vol 3, part B, 4.7.1 */
static int sdp_client_ssa_search(struct bt_sdp_client *session)
{
const struct bt_sdp_discover_params *param;
struct bt_sdp_hdr *hdr;
struct net_buf *buf;
/*
* Select proper user params, if session->param is invalid it means
* getting new UUID from top of to be resolved params list. Otherwise
* the context is in a middle of partial SDP PDU responses and cached
* value from context can be used.
*/
if (!session->param) {
param = GET_PARAM(sys_slist_peek_head(&session->reqs));
} else {
param = session->param;
}
if (!param) {
BT_WARN("No UUIDs to be resolved on remote");
return -EINVAL;
}
buf = bt_l2cap_create_pdu(&sdp_pool, 0);
hdr = net_buf_add(buf, sizeof(*hdr));
hdr->op_code = BT_SDP_SVC_SEARCH_ATTR_REQ;
/* BT_SDP_SEQ8 means length of sequence is on additional next byte */
net_buf_add_u8(buf, BT_SDP_SEQ8);
switch (param->uuid->type) {
case BT_UUID_TYPE_16:
/* Seq length */
net_buf_add_u8(buf, 0x03);
/* Seq type */
net_buf_add_u8(buf, BT_SDP_UUID16);
/* Seq value */
net_buf_add_be16(buf, BT_UUID_16(param->uuid)->val);
break;
case BT_UUID_TYPE_32:
net_buf_add_u8(buf, 0x05);
net_buf_add_u8(buf, BT_SDP_UUID32);
net_buf_add_be32(buf, BT_UUID_32(param->uuid)->val);
break;
case BT_UUID_TYPE_128:
net_buf_add_u8(buf, 0x11);
net_buf_add_u8(buf, BT_SDP_UUID128);
net_buf_add_mem(buf, BT_UUID_128(param->uuid)->val,
ARRAY_SIZE(BT_UUID_128(param->uuid)->val));
break;
default:
BT_ERR("Unknown UUID type %u", param->uuid->type);
return -EINVAL;
}
/* Set attribute max bytes count to be returned from server */
net_buf_add_be16(buf, BT_SDP_MAX_ATTR_LEN);
/*
* Sequence definition where data is sequence of elements and where
* additional next byte points the size of elements within
*/
net_buf_add_u8(buf, BT_SDP_SEQ8);
net_buf_add_u8(buf, 0x05);
/* Data element definition for two following 16bits range elements */
net_buf_add_u8(buf, BT_SDP_UINT32);
/* Get all attributes. It enables filter out wanted only attributes */
net_buf_add_be16(buf, 0x0000);
net_buf_add_be16(buf, 0xffff);
/*
* Update and validate PDU ContinuationState. Initial SSA Request has
* zero length continuation state since no interaction has place with
* server so far, otherwise use the original state taken from remote's
* last response PDU that is cached by SDP client context.
*/
if (session->cstate.length == 0) {
net_buf_add_u8(buf, 0x00);
} else {
net_buf_add_u8(buf, session->cstate.length);
net_buf_add_mem(buf, session->cstate.data,
session->cstate.length);
}
/* set overall PDU length */
hdr->param_len = sys_cpu_to_be16(buf->len - sizeof(*hdr));
/* Update context param to the one being resolving now */
session->param = param;
session->tid++;
hdr->tid = sys_cpu_to_be16(session->tid);
return bt_l2cap_chan_send(&session->chan.chan, buf);
}
static void sdp_client_params_iterator(struct bt_sdp_client *session)
{
struct bt_l2cap_chan *chan = &session->chan.chan;
struct bt_sdp_discover_params *param, *tmp;
SYS_SLIST_FOR_EACH_CONTAINER_SAFE(&session->reqs, param, tmp, _node) {
if (param != session->param) {
continue;
}
BT_DBG("");
/* Remove already checked UUID node */
sys_slist_remove(&session->reqs, NULL, &param->_node);
/* Invalidate cached param in context */
session->param = NULL;
/* Reset continuation state in current context */
(void)memset(&session->cstate, 0, sizeof(session->cstate));
/* Check if there's valid next UUID */
if (!sys_slist_is_empty(&session->reqs)) {
sdp_client_ssa_search(session);
return;
}
/* No UUID items, disconnect channel */
bt_l2cap_chan_disconnect(chan);
break;
}
}
static u16_t sdp_client_get_total(struct bt_sdp_client *session,
struct net_buf *buf, u16_t *total)
{
u16_t pulled;
u8_t seq;
/*
* Pull value of total octets of all attributes available to be
* collected when response gets completed for given UUID. Such info can
* be get from the very first response frame after initial SSA request
* was sent. For subsequent calls related to the same SSA request input
* buf and in/out function parameters stays neutral.
*/
if (session->cstate.length == 0) {
seq = net_buf_pull_u8(buf);
pulled = 1U;
switch (seq) {
case BT_SDP_SEQ8:
*total = net_buf_pull_u8(buf);
pulled += 1;
break;
case BT_SDP_SEQ16:
*total = net_buf_pull_be16(buf);
pulled += 2;
break;
default:
BT_WARN("Sequence type 0x%02x not handled", seq);
*total = 0U;
break;
}
BT_DBG("Total %u octets of all attributes", *total);
} else {
pulled = 0U;
*total = 0U;
}
return pulled;
}
static u16_t get_record_len(struct net_buf *buf)
{
u16_t len;
u8_t seq;
seq = net_buf_pull_u8(buf);
switch (seq) {
case BT_SDP_SEQ8:
len = net_buf_pull_u8(buf);
break;
case BT_SDP_SEQ16:
len = net_buf_pull_be16(buf);
break;
default:
BT_WARN("Sequence type 0x%02x not handled", seq);
len = 0U;
break;
}
BT_DBG("Record len %u", len);
return len;
}
enum uuid_state {
UUID_NOT_RESOLVED,
UUID_RESOLVED,
};
static void sdp_client_notify_result(struct bt_sdp_client *session,
enum uuid_state state)
{
struct bt_conn *conn = session->chan.chan.conn;
struct bt_sdp_client_result result;
u16_t rec_len;
u8_t user_ret;
result.uuid = session->param->uuid;
if (state == UUID_NOT_RESOLVED) {
result.resp_buf = NULL;
result.next_record_hint = false;
session->param->func(conn, &result);
return;
}
while (session->rec_buf->len) {
struct net_buf_simple_state buf_state;
rec_len = get_record_len(session->rec_buf);
/* tell the user about multi record resolution */
if (session->rec_buf->len > rec_len) {
result.next_record_hint = true;
} else {
result.next_record_hint = false;
}
/* save the original session buffer */
net_buf_simple_save(&session->rec_buf->b, &buf_state);
/* initialize internal result buffer instead of memcpy */
result.resp_buf = session->rec_buf;
/*
* Set user internal result buffer length as same as record
* length to fake user. User will see the individual record
* length as rec_len insted of whole session rec_buf length.
*/
result.resp_buf->len = rec_len;
user_ret = session->param->func(conn, &result);
/* restore original session buffer */
net_buf_simple_restore(&session->rec_buf->b, &buf_state);
/*
* sync session buffer data length with next record chunk not
* send to user so far
*/
net_buf_pull(session->rec_buf, rec_len);
if (user_ret == BT_SDP_DISCOVER_UUID_STOP) {
break;
}
}
}
static int sdp_client_receive(struct bt_l2cap_chan *chan, struct net_buf *buf)
{
struct bt_sdp_client *session = SDP_CLIENT_CHAN(chan);
struct bt_sdp_hdr *hdr;
struct bt_sdp_pdu_cstate *cstate;
u16_t len, tid, frame_len;
u16_t total;
BT_DBG("session %p buf %p", session, buf);
if (buf->len < sizeof(*hdr)) {
BT_ERR("Too small SDP PDU");
return 0;
}
hdr = net_buf_pull_mem(buf, sizeof(*hdr));
if (hdr->op_code == BT_SDP_ERROR_RSP) {
BT_INFO("Error SDP PDU response");
return 0;
}
len = sys_be16_to_cpu(hdr->param_len);
tid = sys_be16_to_cpu(hdr->tid);
BT_DBG("SDP PDU tid %u len %u", tid, len);
if (buf->len != len) {
BT_ERR("SDP PDU length mismatch (%u != %u)", buf->len, len);
return 0;
}
if (tid != session->tid) {
BT_ERR("Mismatch transaction ID value in SDP PDU");
return 0;
}
switch (hdr->op_code) {
case BT_SDP_SVC_SEARCH_ATTR_RSP:
/* Get number of attributes in this frame. */
frame_len = net_buf_pull_be16(buf);
/* Check valid buf len for attribute list and cont state */
if (buf->len < frame_len + SDP_CONT_STATE_LEN_SIZE) {
BT_ERR("Invalid frame payload length");
return 0;
}
/* Check valid range of attributes length */
if (frame_len < 2) {
BT_ERR("Invalid attributes data length");
return 0;
}
/* Get PDU continuation state */
cstate = (struct bt_sdp_pdu_cstate *)(buf->data + frame_len);
if (cstate->length > BT_SDP_MAX_PDU_CSTATE_LEN) {
BT_ERR("Invalid SDP PDU Continuation State length %u",
cstate->length);
return 0;
}
if ((frame_len + SDP_CONT_STATE_LEN_SIZE + cstate->length) >
buf->len) {
BT_ERR("Invalid frame payload length");
return 0;
}
/*
* No record found for given UUID. The check catches case when
* current response frame has Continuation State shortest and
* valid and this is the first response frame as well.
*/
if (frame_len == 2 && cstate->length == 0 &&
session->cstate.length == 0) {
BT_DBG("record for UUID 0x%s not found",
bt_uuid_str(session->param->uuid));
/* Call user UUID handler */
sdp_client_notify_result(session, UUID_NOT_RESOLVED);
net_buf_pull(buf, frame_len + sizeof(cstate->length));
goto iterate;
}
/* Get total value of all attributes to be collected */
frame_len -= sdp_client_get_total(session, buf, &total);
if (total > net_buf_tailroom(session->rec_buf)) {
BT_WARN("Not enough room for getting records data");
goto iterate;
}
net_buf_add_mem(session->rec_buf, buf->data, frame_len);
net_buf_pull(buf, frame_len);
/*
* check if current response says there's next portion to be
* fetched
*/
if (cstate->length) {
/* Cache original Continuation State in context */
memcpy(&session->cstate, cstate,
sizeof(struct bt_sdp_pdu_cstate));
net_buf_pull(buf, cstate->length +
sizeof(cstate->length));
/* Request for next portion of attributes data */
sdp_client_ssa_search(session);
break;
}
net_buf_pull(buf, sizeof(cstate->length));
BT_DBG("UUID 0x%s resolved", bt_uuid_str(session->param->uuid));
sdp_client_notify_result(session, UUID_RESOLVED);
iterate:
/* Get next UUID and start resolving it */
sdp_client_params_iterator(session);
break;
default:
BT_DBG("PDU 0x%0x response not handled", hdr->op_code);
break;
}
return 0;
}
static int sdp_client_chan_connect(struct bt_sdp_client *session)
{
return bt_l2cap_br_chan_connect(session->chan.chan.conn,
&session->chan.chan, SDP_PSM);
}
static struct net_buf *sdp_client_alloc_buf(struct bt_l2cap_chan *chan)
{
struct bt_sdp_client *session = SDP_CLIENT_CHAN(chan);
struct net_buf *buf;
BT_DBG("session %p chan %p", session, chan);
session->param = GET_PARAM(sys_slist_peek_head(&session->reqs));
buf = net_buf_alloc(session->param->pool, K_FOREVER);
__ASSERT_NO_MSG(buf);
return buf;
}
static void sdp_client_connected(struct bt_l2cap_chan *chan)
{
struct bt_sdp_client *session = SDP_CLIENT_CHAN(chan);
BT_DBG("session %p chan %p connected", session, chan);
session->rec_buf = chan->ops->alloc_buf(chan);
sdp_client_ssa_search(session);
}
static void sdp_client_disconnected(struct bt_l2cap_chan *chan)
{
struct bt_sdp_client *session = SDP_CLIENT_CHAN(chan);
BT_DBG("session %p chan %p disconnected", session, chan);
net_buf_unref(session->rec_buf);
/*
* Reset session excluding L2CAP channel member. Let's the channel
* resets autonomous.
*/
(void)memset(&session->reqs, 0,
sizeof(*session) - sizeof(session->chan));
}
static struct bt_l2cap_chan_ops sdp_client_chan_ops = {
.connected = sdp_client_connected,
.disconnected = sdp_client_disconnected,
.recv = sdp_client_receive,
.alloc_buf = sdp_client_alloc_buf,
};
static struct bt_sdp_client *sdp_client_new_session(struct bt_conn *conn)
{
int i;
for (i = 0; i < ARRAY_SIZE(bt_sdp_client_pool); i++) {
struct bt_sdp_client *session = &bt_sdp_client_pool[i];
int err;
if (session->chan.chan.conn) {
continue;
}
sys_slist_init(&session->reqs);
session->chan.chan.ops = &sdp_client_chan_ops;
session->chan.chan.conn = conn;
session->chan.rx.mtu = SDP_CLIENT_MTU;
err = sdp_client_chan_connect(session);
if (err) {
(void)memset(session, 0, sizeof(*session));
BT_ERR("Cannot connect %d", err);
return NULL;
}
return session;
}
BT_ERR("No available SDP client context");
return NULL;
}
static struct bt_sdp_client *sdp_client_get_session(struct bt_conn *conn)
{
int i;
for (i = 0; i < ARRAY_SIZE(bt_sdp_client_pool); i++) {
if (bt_sdp_client_pool[i].chan.chan.conn == conn) {
return &bt_sdp_client_pool[i];
}
}
/*
* Try to allocate session context since not found in pool and attempt
* connect to remote SDP endpoint.
*/
return sdp_client_new_session(conn);
}
int bt_sdp_discover(struct bt_conn *conn,
const struct bt_sdp_discover_params *params)
{
struct bt_sdp_client *session;
if (!params || !params->uuid || !params->func || !params->pool) {
BT_WARN("Invalid user params");
return -EINVAL;
}
session = sdp_client_get_session(conn);
if (!session) {
return -ENOMEM;
}
sys_slist_append(&session->reqs, (sys_snode_t *)&params->_node);
return 0;
}
/* Helper getting length of data determined by DTD for integers */
static inline ssize_t sdp_get_int_len(const u8_t *data, size_t len)
{
BT_ASSERT(data);
switch (data[0]) {
case BT_SDP_DATA_NIL:
return 1;
case BT_SDP_BOOL:
case BT_SDP_INT8:
case BT_SDP_UINT8:
if (len < 2) {
break;
}
return 2;
case BT_SDP_INT16:
case BT_SDP_UINT16:
if (len < 3) {
break;
}
return 3;
case BT_SDP_INT32:
case BT_SDP_UINT32:
if (len < 5) {
break;
}
return 5;
case BT_SDP_INT64:
case BT_SDP_UINT64:
if (len < 9) {
break;
}
return 9;
case BT_SDP_INT128:
case BT_SDP_UINT128:
default:
BT_ERR("Invalid/unhandled DTD 0x%02x", data[0]);
return -EINVAL;
}
BT_ERR("Too short buffer length %zu", len);
return -EMSGSIZE;
}
/* Helper getting length of data determined by DTD for UUID */
static inline ssize_t sdp_get_uuid_len(const u8_t *data, size_t len)
{
BT_ASSERT(data);
switch (data[0]) {
case BT_SDP_UUID16:
if (len < 3) {
break;
}
return 3;
case BT_SDP_UUID32:
if (len < 5) {
break;
}
return 5;
case BT_SDP_UUID128:
default:
BT_ERR("Invalid/unhandled DTD 0x%02x", data[0]);
return -EINVAL;
}
BT_ERR("Too short buffer length %zu", len);
return -EMSGSIZE;
}
/* Helper getting length of data determined by DTD for strings */
static inline ssize_t sdp_get_str_len(const u8_t *data, size_t len)
{
const u8_t *pnext;
BT_ASSERT(data);
/* validate len for pnext safe use to read next 8bit value */
if (len < 2) {
goto err;
}
pnext = data + sizeof(u8_t);
switch (data[0]) {
case BT_SDP_TEXT_STR8:
case BT_SDP_URL_STR8:
if (len < (2 + pnext[0])) {
break;
}
return 2 + pnext[0];
case BT_SDP_TEXT_STR16:
case BT_SDP_URL_STR16:
/* validate len for pnext safe use to read 16bit value */
if (len < 3) {
break;
}
if (len < (3 + sys_get_be16(pnext))) {
break;
}
return 3 + sys_get_be16(pnext);
case BT_SDP_TEXT_STR32:
case BT_SDP_URL_STR32:
default:
BT_ERR("Invalid/unhandled DTD 0x%02x", data[0]);
return -EINVAL;
}
err:
BT_ERR("Too short buffer length %zu", len);
return -EMSGSIZE;
}
/* Helper getting length of data determined by DTD for sequences */
static inline ssize_t sdp_get_seq_len(const u8_t *data, size_t len)
{
const u8_t *pnext;
BT_ASSERT(data);
/* validate len for pnext safe use to read 8bit bit value */
if (len < 2) {
goto err;
}
pnext = data + sizeof(u8_t);
switch (data[0]) {
case BT_SDP_SEQ8:
case BT_SDP_ALT8:
if (len < (2 + pnext[0])) {
break;
}
return 2 + pnext[0];
case BT_SDP_SEQ16:
case BT_SDP_ALT16:
/* validate len for pnext safe use to read 16bit value */
if (len < 3) {
break;
}
if (len < (3 + sys_get_be16(pnext))) {
break;
}
return 3 + sys_get_be16(pnext);
case BT_SDP_SEQ32:
case BT_SDP_ALT32:
default:
BT_ERR("Invalid/unhandled DTD 0x%02x", data[0]);
return -EINVAL;
}
err:
BT_ERR("Too short buffer length %zu", len);
return -EMSGSIZE;
}
/* Helper getting length of attribute value data */
static ssize_t sdp_get_attr_value_len(const u8_t *data, size_t len)
{
BT_ASSERT(data);
BT_DBG("Attr val DTD 0x%02x", data[0]);
switch (data[0]) {
case BT_SDP_DATA_NIL:
case BT_SDP_BOOL:
case BT_SDP_UINT8:
case BT_SDP_UINT16:
case BT_SDP_UINT32:
case BT_SDP_UINT64:
case BT_SDP_UINT128:
case BT_SDP_INT8:
case BT_SDP_INT16:
case BT_SDP_INT32:
case BT_SDP_INT64:
case BT_SDP_INT128:
return sdp_get_int_len(data, len);
case BT_SDP_UUID16:
case BT_SDP_UUID32:
case BT_SDP_UUID128:
return sdp_get_uuid_len(data, len);
case BT_SDP_TEXT_STR8:
case BT_SDP_TEXT_STR16:
case BT_SDP_TEXT_STR32:
case BT_SDP_URL_STR8:
case BT_SDP_URL_STR16:
case BT_SDP_URL_STR32:
return sdp_get_str_len(data, len);
case BT_SDP_SEQ8:
case BT_SDP_SEQ16:
case BT_SDP_SEQ32:
case BT_SDP_ALT8:
case BT_SDP_ALT16:
case BT_SDP_ALT32:
return sdp_get_seq_len(data, len);
default:
BT_ERR("Unknown DTD 0x%02x", data[0]);
return -EINVAL;
}
}
/* Type holding UUID item and related to it specific information. */
struct bt_sdp_uuid_desc {
union {
struct bt_uuid uuid;
struct bt_uuid_16 uuid16;
struct bt_uuid_32 uuid32;
};
u16_t attr_id;
u8_t *params;
u16_t params_len;
};
/* Generic attribute item collector. */
struct bt_sdp_attr_item {
/* Attribute identifier. */
u16_t attr_id;
/* Address of beginning attribute value taken from original buffer
* holding response from server.
*/
u8_t *val;
/* Says about the length of attribute value. */
u16_t len;
};
static int bt_sdp_get_attr(const struct net_buf *buf,
struct bt_sdp_attr_item *attr, u16_t attr_id)
{
u8_t *data;
u16_t id;
data = buf->data;
while (data - buf->data < buf->len) {
ssize_t dlen;
/* data need to point to attribute id descriptor field (DTD)*/
if (data[0] != BT_SDP_UINT16) {
BT_ERR("Invalid descriptor 0x%02x", data[0]);
return -EINVAL;
}
data += sizeof(u8_t);
id = sys_get_be16(data);
BT_DBG("Attribute ID 0x%04x", id);
data += sizeof(u16_t);
dlen = sdp_get_attr_value_len(data,
buf->len - (data - buf->data));
if (dlen < 0) {
BT_ERR("Invalid attribute value data");
return -EINVAL;
}
if (id == attr_id) {
BT_DBG("Attribute ID 0x%04x Value found", id);
/*
* Initialize attribute value buffer data using selected
* data slice from original buffer.
*/
attr->val = data;
attr->len = dlen;
attr->attr_id = id;
return 0;
}
data += dlen;
}
return -ENOENT;
}
/* reads SEQ item length, moves input buffer data reader forward */
static ssize_t sdp_get_seq_len_item(u8_t **data, size_t len)
{
const u8_t *pnext;
BT_ASSERT(data);
BT_ASSERT(*data);
/* validate len for pnext safe use to read 8bit bit value */
if (len < 2) {
goto err;
}
pnext = *data + sizeof(u8_t);
switch (*data[0]) {
case BT_SDP_SEQ8:
if (len < (2 + pnext[0])) {
break;
}
*data += 2;
return pnext[0];
case BT_SDP_SEQ16:
/* validate len for pnext safe use to read 16bit value */
if (len < 3) {
break;
}
if (len < (3 + sys_get_be16(pnext))) {
break;
}
*data += 3;
return sys_get_be16(pnext);
case BT_SDP_SEQ32:
/* validate len for pnext safe use to read 32bit value */
if (len < 5) {
break;
}
if (len < (5 + sys_get_be32(pnext))) {
break;
}
*data += 5;
return sys_get_be32(pnext);
default:
BT_ERR("Invalid/unhandled DTD 0x%02x", *data[0]);
return -EINVAL;
}
err:
BT_ERR("Too short buffer length %zu", len);
return -EMSGSIZE;
}
static int sdp_get_uuid_data(const struct bt_sdp_attr_item *attr,
struct bt_sdp_uuid_desc *pd,
u16_t proto_profile)
{
/* get start address of attribute value */
u8_t *p = attr->val;
ssize_t slen;
BT_ASSERT(p);
/* Attribute value is a SEQ, get length of parent SEQ frame */
slen = sdp_get_seq_len_item(&p, attr->len);
if (slen < 0) {
return slen;
}
/* start reading stacked UUIDs in analyzed sequences tree */
while (p - attr->val < attr->len) {
size_t to_end, left = 0;
/* to_end tells how far to the end of input buffer */
to_end = attr->len - (p - attr->val);
/* how long is current UUID's item data associated to */
slen = sdp_get_seq_len_item(&p, to_end);
if (slen < 0) {
return slen;
}
/* left tells how far is to the end of current UUID */
left = slen;
/* check if at least DTD + UUID16 can be read safely */
if (left < 3) {
return -EMSGSIZE;
}
/* check DTD and get stacked UUID value */
switch (p[0]) {
case BT_SDP_UUID16:
memcpy(&pd->uuid16,
BT_UUID_DECLARE_16(sys_get_be16(++p)),
sizeof(struct bt_uuid_16));
p += sizeof(u16_t);
left -= sizeof(u16_t);
break;
case BT_SDP_UUID32:
/* check if valid UUID32 can be read safely */
if (left < 5) {
return -EMSGSIZE;
}
memcpy(&pd->uuid32,
BT_UUID_DECLARE_32(sys_get_be32(++p)),
sizeof(struct bt_uuid_32));
p += sizeof(u32_t);
left -= sizeof(u32_t);
break;
default:
BT_ERR("Invalid/unhandled DTD 0x%02x\n", p[0]);
return -EINVAL;
}
/* include last DTD in p[0] size itself updating left */
left -= sizeof(p[0]);
/*
* Check if current UUID value matches input one given by user.
* If found save it's location and length and return.
*/
if ((proto_profile == BT_UUID_16(&pd->uuid)->val) ||
(proto_profile == BT_UUID_32(&pd->uuid)->val)) {
pd->params = p;
pd->params_len = left;
BT_DBG("UUID 0x%s found", bt_uuid_str(&pd->uuid));
return 0;
}
/* skip left octets to point beginning of next UUID in tree */
p += left;
}
BT_DBG("Value 0x%04x not found", proto_profile);
return -ENOENT;
}
/*
* Helper extracting specific parameters associated with UUID node given in
* protocol descriptor list or profile descriptor list.
*/
static int sdp_get_param_item(struct bt_sdp_uuid_desc *pd_item, u16_t *param)
{
const u8_t *p = pd_item->params;
bool len_err = false;
BT_ASSERT(p);
BT_DBG("Getting UUID's 0x%s params", bt_uuid_str(&pd_item->uuid));
switch (p[0]) {
case BT_SDP_UINT8:
/* check if 8bits value can be read safely */
if (pd_item->params_len < 2) {
len_err = true;
break;
}
*param = (++p)[0];
p += sizeof(u8_t);
break;
case BT_SDP_UINT16:
/* check if 16bits value can be read safely */
if (pd_item->params_len < 3) {
len_err = true;
break;
}
*param = sys_get_be16(++p);
p += sizeof(u16_t);
break;
case BT_SDP_UINT32:
/* check if 32bits value can be read safely */
if (pd_item->params_len < 5) {
len_err = true;
break;
}
*param = sys_get_be32(++p);
p += sizeof(u32_t);
break;
default:
BT_ERR("Invalid/unhandled DTD 0x%02x\n", p[0]);
return -EINVAL;
}
/*
* Check if no more data than already read is associated with UUID. In
* valid case after getting parameter we should reach data buf end.
*/
if (p - pd_item->params != pd_item->params_len || len_err) {
BT_DBG("Invalid param buffer length");
return -EMSGSIZE;
}
return 0;
}
int bt_sdp_get_proto_param(const struct net_buf *buf, enum bt_sdp_proto proto,
u16_t *param)
{
struct bt_sdp_attr_item attr;
struct bt_sdp_uuid_desc pd;
int res;
if (proto != BT_SDP_PROTO_RFCOMM && proto != BT_SDP_PROTO_L2CAP) {
BT_ERR("Invalid protocol specifier");
return -EINVAL;
}
res = bt_sdp_get_attr(buf, &attr, BT_SDP_ATTR_PROTO_DESC_LIST);
if (res < 0) {
BT_WARN("Attribute 0x%04x not found, err %d",
BT_SDP_ATTR_PROTO_DESC_LIST, res);
return res;
}
res = sdp_get_uuid_data(&attr, &pd, proto);
if (res < 0) {
BT_WARN("Protocol specifier 0x%04x not found, err %d", proto,
res);
return res;
}
return sdp_get_param_item(&pd, param);
}
int bt_sdp_get_profile_version(const struct net_buf *buf, u16_t profile,
u16_t *version)
{
struct bt_sdp_attr_item attr;
struct bt_sdp_uuid_desc pd;
int res;
res = bt_sdp_get_attr(buf, &attr, BT_SDP_ATTR_PROFILE_DESC_LIST);
if (res < 0) {
BT_WARN("Attribute 0x%04x not found, err %d",
BT_SDP_ATTR_PROFILE_DESC_LIST, res);
return res;
}
res = sdp_get_uuid_data(&attr, &pd, profile);
if (res < 0) {
BT_WARN("Profile 0x%04x not found, err %d", profile, res);
return res;
}
return sdp_get_param_item(&pd, version);
}
int bt_sdp_get_features(const struct net_buf *buf, u16_t *features)
{
struct bt_sdp_attr_item attr;
const u8_t *p;
int res;
res = bt_sdp_get_attr(buf, &attr, BT_SDP_ATTR_SUPPORTED_FEATURES);
if (res < 0) {
BT_WARN("Attribute 0x%04x not found, err %d",
BT_SDP_ATTR_SUPPORTED_FEATURES, res);
return res;
}
p = attr.val;
BT_ASSERT(p);
if (p[0] != BT_SDP_UINT16) {
BT_ERR("Invalid DTD 0x%02x", p[0]);
return -EINVAL;
}
/* assert 16bit can be read safely */
if (attr.len < 3) {
BT_ERR("Data length too short %u", attr.len);
return -EMSGSIZE;
}
*features = sys_get_be16(++p);
p += sizeof(u16_t);
if (p - attr.val != attr.len) {
BT_ERR("Invalid data length %u", attr.len);
return -EMSGSIZE;
}
return 0;
}
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