/*---------------------------------------------------------------------------*/
PROCESS_THREAD(udp_socket_process, ev, data, buf, user_data)
{
struct udp_socket *c;
PROCESS_BEGIN();
while(1) {
PROCESS_WAIT_EVENT();
if(ev == tcpip_event) {
/* An appstate pointer is passed to use from the IP stack
through the 'data' pointer. We registered this appstate when
we did the udp_new() call in udp_socket_register() as the
struct udp_socket pointer. So we extract this
pointer and use it when calling the reception callback. */
c = (struct udp_socket *)data;
/* Defensive coding: although the appstate *should* be non-null
here, we make sure to avoid the program crashing on us. */
if(c != NULL) {
/* If we were called because of incoming data, we should call
the reception callback. */
if(uip_newdata(buf)) {
/* Copy the data from the uIP data buffer into our own
buffer to avoid the uIP buffer being messed with by the
callee. */
#if 0
/* Note that we cannot do this as the stack is suppose to be
* re-entrant.
*/
memcpy(bad_buf, uip_appdata(buf), uip_datalen(buf));
#endif
/* Call the client process. We use the PROCESS_CONTEXT
mechanism to temporarily switch process context to the
client process. */
if(c->input_callback != NULL) {
PROCESS_CONTEXT_BEGIN(c->p);
c->input_callback(c, c->ptr,
&(UIP_IP_BUF(buf)->srcipaddr),
UIP_HTONS(UIP_IP_BUF(buf)->srcport),
&(UIP_IP_BUF(buf)->destipaddr),
UIP_HTONS(UIP_IP_BUF(buf)->destport),
uip_buf(buf), uip_datalen(buf));
PROCESS_CONTEXT_END();
}
}
}
}
}
PROCESS_END();
}
/*---------------------------------------------------------------------------*/
static void
check_for_tcp_syn(struct net_buf *buf)
{
#if UIP_TCP || UIP_CONF_IP_FORWARD
/* This is a hack that is needed to start the periodic TCP timer if
an incoming packet contains a SYN: since uIP does not inform the
application if a SYN arrives, we have no other way of starting
this timer. This function is called for every incoming IP packet
to check for such SYNs. */
#define TCP_SYN 0x02
if(UIP_IP_BUF(buf)->proto == UIP_PROTO_TCP &&
(UIP_TCP_BUF(buf)->flags & TCP_SYN) == TCP_SYN) {
start_periodic_tcp_timer();
}
#endif /* UIP_TCP || UIP_CONF_IP_FORWARD */
}
/*---------------------------------------------------------------------------*/
int coap_context_wait_data(coap_context_t *coap_ctx, int32_t ticks)
{
struct net_buf *buf;
buf = net_receive(coap_ctx->net_ctx, ticks);
if (buf) {
session_t session;
int ret;
uip_ipaddr_copy(&session.addr.ipaddr, &UIP_IP_BUF(buf)->srcipaddr);
session.addr.port = UIP_UDP_BUF(buf)->srcport;
session.size = sizeof(session.addr);
session.ifindex = 1;
PRINTF("coap-context: got dtls message from ");
PRINT6ADDR(&session.addr.ipaddr);
PRINTF(":%d %u bytes\n", uip_ntohs(session.addr.port), uip_appdatalen(buf));
PRINTF("Received appdata %p appdatalen %d\n",
ip_buf_appdata(buf), ip_buf_appdatalen(buf));
coap_ctx->buf = buf;
ret = dtls_handle_message(coap_ctx->dtls_context, &session,
ip_buf_appdata(buf), ip_buf_appdatalen(buf));
/* We always release the buffer here as this buffer is never sent
* to network anyway.
*/
if (coap_ctx->buf) {
ip_buf_unref(coap_ctx->buf);
coap_ctx->buf = NULL;
}
return ret;
}
return 0;
}
/*---------------------------------------------------------------------------*/
int coap_context_wait_data(coap_context_t *coap_ctx, int32_t ticks)
{
struct net_buf *buf;
buf = net_receive(coap_ctx->net_ctx, ticks);
if (buf) {
PRINTF("coap-context: got message from ");
PRINT6ADDR(&UIP_IP_BUF(buf)->srcipaddr);
PRINTF(":%d %u bytes\n", uip_ntohs(UIP_UDP_BUF(buf)->srcport),
uip_appdatalen(buf));
PRINTF("Received data appdata %p appdatalen %d\n",
ip_buf_appdata(buf), ip_buf_appdatalen(buf));
coap_ctx->buf = buf;
coap_engine_receive(coap_ctx);
return 1;
}
return 0;
}
/* Switch the ports and addresses and set route and neighbor cache.
* Returns 1 if packet was sent properly, in this case it is the caller
* that needs to release the net_buf. If 0 is returned, then uIP stack
* has released the net_buf already because there was an some net related
* error when sending the buffer.
*/
static inline int udp_prepare_and_send(struct net_context *context,
struct net_buf *buf)
{
#ifdef CONFIG_NETWORKING_WITH_IPV6
uip_ds6_route_t *route_old, *route_new = NULL;
uip_ds6_nbr_t *nbr;
#endif
uip_ipaddr_t tmp;
uint16_t port;
uint8_t ret;
if (uip_len(buf) == 0) {
/* This is expected as uIP will typically set the
* packet length to 0 after receiving it. So we need
* to fix the length here. The protocol specific
* part is added also here.
*/
uip_len(buf) = uip_slen(buf) = uip_appdatalen(buf);
buf->data = buf->buf + UIP_IPUDPH_LEN;
}
port = UIP_UDP_BUF(buf)->srcport;
UIP_UDP_BUF(buf)->srcport = UIP_UDP_BUF(buf)->destport;
UIP_UDP_BUF(buf)->destport = port;
uip_ipaddr_copy(&tmp, &UIP_IP_BUF(buf)->srcipaddr);
uip_ipaddr_copy(&UIP_IP_BUF(buf)->srcipaddr,
&UIP_IP_BUF(buf)->destipaddr);
uip_ipaddr_copy(&UIP_IP_BUF(buf)->destipaddr, &tmp);
#ifdef CONFIG_NETWORKING_WITH_IPV6
/* The peer needs to be in neighbor cache before route can be added.
*/
nbr = uip_ds6_nbr_lookup((uip_ipaddr_t *)&UIP_IP_BUF(buf)->destipaddr);
if (!nbr) {
const uip_lladdr_t *lladdr = (const uip_lladdr_t *)&buf->src;
nbr = uip_ds6_nbr_add(
(uip_ipaddr_t *)&UIP_IP_BUF(buf)->destipaddr,
lladdr, 0, NBR_REACHABLE);
if (!nbr) {
NET_DBG("Cannot add peer ");
PRINT6ADDR(&UIP_IP_BUF(buf)->destipaddr);
PRINT(" to neighbor cache\n");
}
}
/* Temporarily add route to peer, delete the route after
* sending the packet. Check if there was already a
* route and do not remove it if there was existing
* route to this peer.
*/
route_old = uip_ds6_route_lookup(&UIP_IP_BUF(buf)->destipaddr);
if (!route_old) {
route_new = uip_ds6_route_add(&UIP_IP_BUF(buf)->destipaddr,
128,
&UIP_IP_BUF(buf)->destipaddr);
if (!route_new) {
NET_DBG("Cannot add route to peer ");
PRINT6ADDR(&UIP_IP_BUF(buf)->destipaddr);
PRINT("\n");
}
}
#endif
ret = simple_udp_sendto_port(buf,
net_context_get_udp_connection(context),
buf->data, buf->len,
&UIP_IP_BUF(buf)->destipaddr,
uip_ntohs(UIP_UDP_BUF(buf)->destport));
if (!ret) {
NET_DBG("Packet could not be sent properly.\n");
}
#ifdef CONFIG_NETWORKING_WITH_IPV6
if (!route_old && route_new) {
/* This will also remove the neighbor cache entry */
uip_ds6_route_rm(route_new);
}
#endif
return ret;
}
/*---------------------------------------------------------------------------*/
int
coap_engine_receive(coap_context_t *coap_ctx)
{
erbium_status_code = NO_ERROR;
coap_packet_t message[1]; /* this way the packet can be treated as pointer as usual */
coap_packet_t response[1];
coap_transaction_t *transaction = NULL;
PRINTF("%s(): received data len %u\n", __FUNCTION__,
(uint16_t)uip_appdatalen(coap_ctx->buf));
if(uip_newdata(coap_ctx->buf)) {
PRINTF("receiving UDP datagram from: ");
PRINT6ADDR(&UIP_IP_BUF(coap_ctx->buf)->srcipaddr);
PRINTF(":%u\n Length: %u\n",
uip_ntohs(UIP_UDP_BUF(coap_ctx->buf)->srcport),
uip_appdatalen(coap_ctx->buf));
erbium_status_code =
coap_parse_message(message, uip_appdata(coap_ctx->buf), uip_appdatalen(coap_ctx->buf));
coap_set_context(message, coap_ctx);
if(erbium_status_code == NO_ERROR) {
NET_COAP_STAT(recv++);
/*TODO duplicates suppression, if required by application */
PRINTF(" Parsed: v %u, t %u, tkl %u, c %u, mid %u\n", message->version,
message->type, message->token_len, message->code, message->mid);
PRINTF(" URL[%d]: %.*s\n", message->uri_path_len, message->uri_path_len, message->uri_path);
PRINTF(" Payload[%d]: %.*s\n", message->payload_len, message->payload_len, message->payload);
/* handle requests */
if(message->code >= COAP_GET && message->code <= COAP_DELETE) {
/* use transaction buffer for response to confirmable request */
if((transaction = coap_new_transaction(message->mid, coap_ctx,
&UIP_IP_BUF(coap_ctx->buf)->srcipaddr,
UIP_UDP_BUF(coap_ctx->buf)->srcport))) {
uint32_t block_num = 0;
uint16_t block_size = REST_MAX_CHUNK_SIZE;
uint32_t block_offset = 0;
int32_t new_offset = 0;
/* prepare response */
if(message->type == COAP_TYPE_CON) {
/* reliable CON requests are answered with an ACK */
coap_init_message(response, COAP_TYPE_ACK, CONTENT_2_05,
message->mid);
} else {
/* unreliable NON requests are answered with a NON as well */
coap_init_message(response, COAP_TYPE_NON, CONTENT_2_05,
coap_get_mid());
/* mirror token */
} if(message->token_len) {
coap_set_token(response, message->token, message->token_len);
/* get offset for blockwise transfers */
}
if(coap_get_header_block2
(message, &block_num, NULL, &block_size, &block_offset)) {
PRINTF("Blockwise: block request %lu (%u/%u) @ %lu bytes\n",
(unsigned long)block_num, block_size, REST_MAX_CHUNK_SIZE, (unsigned long)block_offset);
block_size = MIN(block_size, REST_MAX_CHUNK_SIZE);
new_offset = block_offset;
}
/* invoke resource handler */
if(service_cbk) {
/* call REST framework and check if found and allowed */
if(service_cbk
(message, response, transaction->packet + COAP_MAX_HEADER_SIZE,
block_size, &new_offset)) {
if(erbium_status_code == NO_ERROR) {
/* TODO coap_handle_blockwise(request, response, start_offset, end_offset); */
/* resource is unaware of Block1 */
if(IS_OPTION(message, COAP_OPTION_BLOCK1)
&& response->code < BAD_REQUEST_4_00
&& !IS_OPTION(response, COAP_OPTION_BLOCK1)) {
PRINTF("Block1 NOT IMPLEMENTED\n");
erbium_status_code = NOT_IMPLEMENTED_5_01;
coap_error_message = "NoBlock1Support";
/* client requested Block2 transfer */
} else if(IS_OPTION(message, COAP_OPTION_BLOCK2)) {
/* unchanged new_offset indicates that resource is unaware of blockwise transfer */
if(new_offset == block_offset) {
PRINTF
("Blockwise: unaware resource with payload length %u/%u\n",
response->payload_len, block_size);
if(block_offset >= response->payload_len) {
PRINTF
("handle_incoming_data(): block_offset >= response->payload_len\n");
response->code = BAD_OPTION_4_02;
coap_set_payload(response, "BlockOutOfScope", 15); /* a const char str[] and sizeof(str) produces larger code size */
} else {
coap_set_header_block2(response, block_num,
response->payload_len -
block_offset > block_size,
block_size);
coap_set_payload(response,
response->payload + block_offset,
MIN(response->payload_len -
block_offset, block_size));
} /* if(valid offset) */
/* resource provides chunk-wise data */
} else {
PRINTF("Blockwise: blockwise resource, new offset %ld\n",
(long)new_offset);
coap_set_header_block2(response, block_num,
new_offset != -1
|| response->payload_len >
block_size, block_size);
if(response->payload_len > block_size) {
coap_set_payload(response, response->payload,
block_size);
}
} /* if(resource aware of blockwise) */
/* Resource requested Block2 transfer */
} else if(new_offset != 0) {
PRINTF
("Blockwise: no block option for blockwise resource, using block size %u\n",
COAP_MAX_BLOCK_SIZE);
coap_set_header_block2(response, 0, new_offset != -1,
COAP_MAX_BLOCK_SIZE);
coap_set_payload(response, response->payload,
MIN(response->payload_len,
COAP_MAX_BLOCK_SIZE));
} /* blockwise transfer handling */
} /* no errors/hooks */
/* successful service callback */
/* serialize response */
}
if(erbium_status_code == NO_ERROR) {
if((transaction->packet_len = coap_serialize_message(response,
transaction->
packet)) ==
0) {
erbium_status_code = PACKET_SERIALIZATION_ERROR;
}
}
} else {
erbium_status_code = NOT_IMPLEMENTED_5_01;
coap_error_message = "NoServiceCallbck"; /* no 'a' to fit into 16 bytes */
} /* if(service callback) */
} else {
erbium_status_code = SERVICE_UNAVAILABLE_5_03;
coap_error_message = "NoFreeTraBuffer";
} /* if(transaction buffer) */
/* handle responses */
} else {
if(message->type == COAP_TYPE_CON && message->code == 0) {
PRINTF("Received Ping\n");
erbium_status_code = PING_RESPONSE;
} else if(message->type == COAP_TYPE_ACK) {
/* transactions are closed through lookup below */
PRINTF("Received ACK\n");
} else if(message->type == COAP_TYPE_RST) {
PRINTF("Received RST\n");
/* cancel possible subscriptions */
coap_remove_observer_by_mid(coap_ctx, &UIP_IP_BUF(coap_ctx->buf)->srcipaddr,
UIP_UDP_BUF(coap_ctx->buf)->srcport, message->mid);
}
if((transaction = coap_get_transaction_by_mid(message->mid))) {
/* free transaction memory before callback, as it may create a new transaction */
restful_response_handler callback = transaction->callback;
void *callback_data = transaction->callback_data;
coap_clear_transaction(transaction);
/* check if someone registered for the response */
if(callback) {
callback(callback_data, message);
}
}
/* if(ACKed transaction) */
transaction = NULL;
#if COAP_OBSERVE_CLIENT
/* if observe notification */
if((message->type == COAP_TYPE_CON || message->type == COAP_TYPE_NON)
&& IS_OPTION(message, COAP_OPTION_OBSERVE)) {
PRINTF("Observe [%u]\n", message->observe);
coap_handle_notification(coap_ctx, &UIP_IP_BUF(coap_ctx->buf)->srcipaddr,
UIP_UDP_BUF(coap_ctx->buf)->srcport, message);
}
#endif /* COAP_OBSERVE_CLIENT */
} /* request or response */
} else { /* parsed correctly */
NET_COAP_STAT(recv_err++);
}
/* if(parsed correctly) */
if(erbium_status_code == NO_ERROR) {
if(transaction) {
coap_send_transaction(transaction);
}
} else if(erbium_status_code == MANUAL_RESPONSE) {
PRINTF("Clearing transaction for manual response");
coap_clear_transaction(transaction);
} else {
coap_message_type_t reply_type = COAP_TYPE_ACK;
PRINTF("ERROR %u: %s\n", erbium_status_code, coap_error_message);
coap_clear_transaction(transaction);
if(erbium_status_code == PING_RESPONSE) {
erbium_status_code = 0;
reply_type = COAP_TYPE_RST;
} else if(erbium_status_code >= 192) {
/* set to sendable error code */
erbium_status_code = INTERNAL_SERVER_ERROR_5_00;
/* reuse input buffer for error message */
}
coap_init_message(message, reply_type, erbium_status_code,
message->mid);
coap_set_payload(message, coap_error_message,
strlen(coap_error_message));
coap_send_message(coap_ctx, &UIP_IP_BUF(coap_ctx->buf)->srcipaddr,
UIP_UDP_BUF(coap_ctx->buf)->srcport,
uip_appdata(coap_ctx->buf),
coap_serialize_message(message,
uip_appdata(coap_ctx->buf)));
}
}
/* if(new data) */
return erbium_status_code;
}
uint8_t
tcpip_ipv6_output(struct net_buf *buf)
{
uip_ds6_nbr_t *nbr = NULL;
uip_ipaddr_t *nexthop;
uint8_t ret = 0; /* return value 0 == failed, 1 == ok */
PRINTF("%s(): buf %p len %d\n", __FUNCTION__, buf, uip_len(buf));
if(uip_len(buf) == 0) {
return 0;
}
if(uip_len(buf) > UIP_LINK_MTU) {
UIP_LOG("tcpip_ipv6_output: Packet to big");
uip_len(buf) = 0;
return 0;
}
if(uip_is_addr_unspecified(&UIP_IP_BUF(buf)->destipaddr)){
UIP_LOG("tcpip_ipv6_output: Destination address unspecified");
uip_len(buf) = 0;
return 0;
}
if(!uip_is_addr_mcast(&UIP_IP_BUF(buf)->destipaddr)) {
/* Next hop determination */
nbr = NULL;
/* We first check if the destination address is on our immediate
link. If so, we simply use the destination address as our
nexthop address. */
if(uip_ds6_is_addr_onlink(&UIP_IP_BUF(buf)->destipaddr)){
nexthop = &UIP_IP_BUF(buf)->destipaddr;
} else {
uip_ds6_route_t *route;
/* Check if we have a route to the destination address. */
route = uip_ds6_route_lookup(&UIP_IP_BUF(buf)->destipaddr);
/* No route was found - we send to the default route instead. */
if(route == NULL) {
PRINTF("tcpip_ipv6_output: no route found, using default route\n");
nexthop = uip_ds6_defrt_choose();
if(nexthop == NULL) {
#ifdef UIP_FALLBACK_INTERFACE
PRINTF("FALLBACK: removing ext hdrs & setting proto %d %d\n",
uip_ext_len(buf), *((uint8_t *)UIP_IP_BUF(buf) + 40));
if(uip_ext_len(buf) > 0) {
extern void remove_ext_hdr(void);
uint8_t proto = *((uint8_t *)UIP_IP_BUF(buf) + 40);
remove_ext_hdr();
/* This should be copied from the ext header... */
UIP_IP_BUF(buf)->proto = proto;
}
UIP_FALLBACK_INTERFACE.output();
#else
PRINTF("tcpip_ipv6_output: Destination off-link but no route\n");
#endif /* !UIP_FALLBACK_INTERFACE */
uip_len(buf) = 0;
return 0;
}
} else {
/* A route was found, so we look up the nexthop neighbor for
the route. */
nexthop = uip_ds6_route_nexthop(route);
/* If the nexthop is dead, for example because the neighbor
never responded to link-layer acks, we drop its route. */
if(nexthop == NULL) {
#if UIP_CONF_IPV6_RPL
/* If we are running RPL, and if we are the root of the
network, we'll trigger a global repair berfore we remove
the route. */
rpl_dag_t *dag;
rpl_instance_t *instance;
dag = (rpl_dag_t *)route->state.dag;
if(dag != NULL) {
instance = dag->instance;
rpl_repair_root(buf, instance->instance_id);
}
#endif /* UIP_CONF_IPV6_RPL */
uip_ds6_route_rm(route);
/* We don't have a nexthop to send the packet to, so we drop
it. */
return 0;
}
}
#if TCPIP_CONF_ANNOTATE_TRANSMISSIONS
if(nexthop != NULL) {
static uint8_t annotate_last;
static uint8_t annotate_has_last = 0;
if(annotate_has_last) {
printf("#L %u 0; red\n", annotate_last);
}
printf("#L %u 1; red\n", nexthop->u8[sizeof(uip_ipaddr_t) - 1]);
annotate_last = nexthop->u8[sizeof(uip_ipaddr_t) - 1];
annotate_has_last = 1;
}
#endif /* TCPIP_CONF_ANNOTATE_TRANSMISSIONS */
}
/* End of next hop determination */
#if UIP_CONF_IPV6_RPL
if(rpl_update_header_final(buf, nexthop)) {
uip_len(buf) = 0;
return 0;
}
#endif /* UIP_CONF_IPV6_RPL */
nbr = uip_ds6_nbr_lookup(nexthop);
if(nbr == NULL) {
#if UIP_ND6_SEND_NA
if((nbr = uip_ds6_nbr_add(nexthop, NULL, 0, NBR_INCOMPLETE)) == NULL) {
uip_len(buf) = 0;
return 0;
} else {
#if UIP_CONF_IPV6_QUEUE_PKT
/* Copy outgoing pkt in the queuing buffer for later transmit. */
if(uip_packetqueue_alloc(&nbr->packethandle, UIP_DS6_NBR_PACKET_LIFETIME) != NULL) {
memcpy(uip_packetqueue_buf(&nbr->packethandle), UIP_IP_BUF(buf), uip_len(buf));
uip_packetqueue_set_buflen(&nbr->packethandle, uip_len(buf));
}
#endif
/* RFC4861, 7.2.2:
* "If the source address of the packet prompting the solicitation is the
* same as one of the addresses assigned to the outgoing interface, that
* address SHOULD be placed in the IP Source Address of the outgoing
* solicitation. Otherwise, any one of the addresses assigned to the
* interface should be used."*/
if(uip_ds6_is_my_addr(&UIP_IP_BUF(buf)->srcipaddr)){
uip_nd6_ns_output(buf, &UIP_IP_BUF(buf)->srcipaddr, NULL, &nbr->ipaddr);
} else {
uip_nd6_ns_output(buf, NULL, NULL, &nbr->ipaddr);
}
stimer_set(&nbr->sendns, uip_ds6_if.retrans_timer / 1000);
nbr->nscount = 1;
}
return 1; /* packet was passed to network successfully */
#endif /* UIP_ND6_SEND_NA */
} else {
#if UIP_ND6_SEND_NA
if(nbr->state == NBR_INCOMPLETE) {
PRINTF("tcpip_ipv6_output: nbr cache entry incomplete\n");
#if UIP_CONF_IPV6_QUEUE_PKT
/* Copy outgoing pkt in the queuing buffer for later transmit and set
the destination nbr to nbr. */
if(uip_packetqueue_alloc(&nbr->packethandle, UIP_DS6_NBR_PACKET_LIFETIME) != NULL) {
memcpy(uip_packetqueue_buf(&nbr->packethandle), UIP_IP_BUF(buf), uip_len(buf));
uip_packetqueue_set_buflen(&nbr->packethandle, uip_len(buf));
}
#endif /*UIP_CONF_IPV6_QUEUE_PKT*/
uip_len(buf) = 0;
return 0;
}
/* Send in parallel if we are running NUD (nbc state is either STALE,
DELAY, or PROBE). See RFC 4861, section 7.3.3 on node behavior. */
if(nbr->state == NBR_STALE) {
nbr->state = NBR_DELAY;
stimer_set(&nbr->reachable, UIP_ND6_DELAY_FIRST_PROBE_TIME);
nbr->nscount = 0;
PRINTF("tcpip_ipv6_output: nbr cache entry stale moving to delay\n");
}
#endif /* UIP_ND6_SEND_NA */
ret = tcpip_output(buf, uip_ds6_nbr_get_ll(nbr));
#if UIP_CONF_IPV6_QUEUE_PKT
/*
* Send the queued packets from here, may not be 100% perfect though.
* This happens in a few cases, for example when instead of receiving a
* NA after sendiong a NS, you receive a NS with SLLAO: the entry moves
* to STALE, and you must both send a NA and the queued packet.
*/
if(uip_packetqueue_buflen(&nbr->packethandle) != 0) {
uip_len(buf) = uip_packetqueue_buflen(&nbr->packethandle);
memcpy(UIP_IP_BUF(buf), uip_packetqueue_buf(&nbr->packethandle), uip_len(buf));
uip_packetqueue_free(&nbr->packethandle);
ret = tcpip_output(uip_ds6_nbr_get_ll(nbr));
}
#endif /*UIP_CONF_IPV6_QUEUE_PKT*/
if (ret == 0) {
uip_len(buf) = 0;
}
return ret;
}
return 0; /* discard packet */
}
/* Multicast IP destination address. */
ret = tcpip_output(buf, NULL);
uip_len(buf) = 0;
uip_ext_len(buf) = 0;
return ret;
}
static int fragment(struct net_buf *buf, void *ptr)
{
struct queuebuf *q;
int max_payload;
int framer_hdrlen;
uint16_t frag_tag;
/* Number of bytes processed. */
uint16_t processed_ip_out_len;
struct net_buf *mbuf;
bool last_fragment = false;
#define USE_FRAMER_HDRLEN 0
#if USE_FRAMER_HDRLEN
framer_hdrlen = NETSTACK_FRAMER.length();
if(framer_hdrlen < 0) {
/* Framing failed, we assume the maximum header length */
framer_hdrlen = 21;
}
#else /* USE_FRAMER_HDRLEN */
framer_hdrlen = 21;
#endif /* USE_FRAMER_HDRLEN */
max_payload = MAC_MAX_PAYLOAD - framer_hdrlen - NETSTACK_LLSEC.get_overhead();
PRINTF("max_payload: %d, framer_hdrlen: %d \n",max_payload, framer_hdrlen);
mbuf = l2_buf_get_reserve(0);
if (!mbuf) {
goto fail;
}
uip_last_tx_status(mbuf) = MAC_TX_OK;
/*
* The destination address will be tagged to each outbound
* packet. If the argument localdest is NULL, we are sending a
* broadcast packet.
*/
if((int)uip_len(buf) <= max_payload) {
/* The packet does not need to be fragmented, send buf */
packetbuf_copyfrom(mbuf, uip_buf(buf), uip_len(buf));
send_packet(mbuf, &ip_buf_ll_dest(buf), true, ptr);
ip_buf_unref(buf);
return 1;
}
uip_uncomp_hdr_len(mbuf) = 0;
uip_packetbuf_hdr_len(mbuf) = 0;
packetbuf_clear(mbuf);
uip_packetbuf_ptr(mbuf) = packetbuf_dataptr(mbuf);
packetbuf_set_attr(mbuf, PACKETBUF_ATTR_MAX_MAC_TRANSMISSIONS,
SICSLOWPAN_MAX_MAC_TRANSMISSIONS);
PRINTF("fragmentation: total packet len %d\n", uip_len(buf));
/*
* The outbound IPv6 packet is too large to fit into a single 15.4
* packet, so we fragment it into multiple packets and send them.
* The first fragment contains frag1 dispatch, then
* IPv6/HC1/HC06/HC_UDP dispatchs/headers.
* The following fragments contain only the fragn dispatch.
*/
int estimated_fragments = ((int)uip_len(buf)) / ((int)MAC_MAX_PAYLOAD - SICSLOWPAN_FRAGN_HDR_LEN) + 1;
int freebuf = queuebuf_numfree(mbuf) - 1;
PRINTF("uip_len: %d, fragments: %d, free bufs: %d\n", uip_len(buf), estimated_fragments, freebuf);
if(freebuf < estimated_fragments) {
PRINTF("Dropping packet, not enough free bufs\n");
goto fail;
}
/* Create 1st Fragment */
SET16(uip_packetbuf_ptr(mbuf), PACKETBUF_FRAG_DISPATCH_SIZE,
((SICSLOWPAN_DISPATCH_FRAG1 << 8) | uip_len(buf)));
frag_tag = my_tag++;
SET16(uip_packetbuf_ptr(mbuf), PACKETBUF_FRAG_TAG, frag_tag);
PRINTF("fragmentation: fragment %d \n", frag_tag);
/* Copy payload and send */
uip_packetbuf_hdr_len(mbuf) += SICSLOWPAN_FRAG1_HDR_LEN;
uip_packetbuf_payload_len(mbuf) = (max_payload - uip_packetbuf_hdr_len(mbuf)) & 0xfffffff8;
PRINTF("(payload len %d, hdr len %d, tag %d)\n",
uip_packetbuf_payload_len(mbuf), uip_packetbuf_hdr_len(mbuf), frag_tag);
memcpy(uip_packetbuf_ptr(mbuf) + uip_packetbuf_hdr_len(mbuf),
uip_buf(buf), uip_packetbuf_payload_len(mbuf));
packetbuf_set_datalen(mbuf, uip_packetbuf_payload_len(mbuf) + uip_packetbuf_hdr_len(mbuf));
q = queuebuf_new_from_packetbuf(mbuf);
if(q == NULL) {
PRINTF("could not allocate queuebuf for first fragment, dropping packet\n");
goto fail;
}
net_buf_ref(mbuf);
send_packet(mbuf, &ip_buf_ll_dest(buf), last_fragment, ptr);
queuebuf_to_packetbuf(mbuf, q);
queuebuf_free(q);
q = NULL;
/* Check tx result. */
if((uip_last_tx_status(mbuf) == MAC_TX_COLLISION) ||
(uip_last_tx_status(mbuf) == MAC_TX_ERR) ||
(uip_last_tx_status(mbuf) == MAC_TX_ERR_FATAL)) {
PRINTF("error in fragment tx, dropping subsequent fragments.\n");
goto fail;
}
/* set processed_ip_out_len to what we already sent from the IP payload*/
processed_ip_out_len = uip_packetbuf_payload_len(mbuf);
/*
* Create following fragments
* Datagram tag is already in the buffer, we need to set the
* FRAGN dispatch and for each fragment, the offset
*/
uip_packetbuf_hdr_len(mbuf) = SICSLOWPAN_FRAGN_HDR_LEN;
SET16(uip_packetbuf_ptr(mbuf), PACKETBUF_FRAG_DISPATCH_SIZE,
((SICSLOWPAN_DISPATCH_FRAGN << 8) | uip_len(buf)));
uip_packetbuf_payload_len(mbuf) = (max_payload - uip_packetbuf_hdr_len(mbuf)) & 0xfffffff8;
while(processed_ip_out_len < uip_len(buf)) {
PRINTF("fragmentation: fragment:%d, processed_ip_out_len:%d \n", my_tag, processed_ip_out_len);
uip_packetbuf_ptr(mbuf)[PACKETBUF_FRAG_OFFSET] = processed_ip_out_len >> 3;
/* Copy payload and send */
if(uip_len(buf) - processed_ip_out_len < uip_packetbuf_payload_len(mbuf)) {
/* last fragment */
last_fragment = true;
uip_packetbuf_payload_len(mbuf) = uip_len(buf) - processed_ip_out_len;
}
PRINTF("(offset %d, len %d, tag %d)\n",
processed_ip_out_len >> 3, uip_packetbuf_payload_len(mbuf), my_tag);
memcpy(uip_packetbuf_ptr(mbuf) + uip_packetbuf_hdr_len(mbuf),
(uint8_t *)UIP_IP_BUF(buf) + processed_ip_out_len, uip_packetbuf_payload_len(mbuf));
packetbuf_set_datalen(mbuf, uip_packetbuf_payload_len(mbuf) + uip_packetbuf_hdr_len(mbuf));
q = queuebuf_new_from_packetbuf(mbuf);
if(q == NULL) {
PRINTF("could not allocate queuebuf, dropping fragment\n");
goto fail;
}
net_buf_ref(mbuf);
send_packet(mbuf, &ip_buf_ll_dest(buf), last_fragment, ptr);
queuebuf_to_packetbuf(mbuf, q);
queuebuf_free(q);
q = NULL;
processed_ip_out_len += uip_packetbuf_payload_len(mbuf);
/* Check tx result. */
if((uip_last_tx_status(mbuf) == MAC_TX_COLLISION) ||
(uip_last_tx_status(mbuf) == MAC_TX_ERR) ||
(uip_last_tx_status(mbuf) == MAC_TX_ERR_FATAL)) {
PRINTF("error in fragment tx, dropping subsequent fragments.\n");
goto fail;
}
}
ip_buf_unref(buf);
l2_buf_unref(mbuf);
return 1;
fail:
if (mbuf) {
l2_buf_unref(mbuf);
}
return 0;
}
