diff options
Diffstat (limited to 'lwip/src/core/udp.c')
| -rw-r--r-- | lwip/src/core/udp.c | 1314 |
1 files changed, 1314 insertions, 0 deletions
diff --git a/lwip/src/core/udp.c b/lwip/src/core/udp.c new file mode 100644 index 0000000..9d2cb4a --- /dev/null +++ b/lwip/src/core/udp.c @@ -0,0 +1,1314 @@ +/** + * @file + * User Datagram Protocol module\n + * The code for the User Datagram Protocol UDP & UDPLite (RFC 3828).\n + * See also @ref udp_raw + * + * @defgroup udp_raw UDP + * @ingroup callbackstyle_api + * User Datagram Protocol module\n + * @see @ref api + */ + +/* + * Copyright (c) 2001-2004 Swedish Institute of Computer Science. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without modification, + * are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT + * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, + * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT + * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING + * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY + * OF SUCH DAMAGE. + * + * This file is part of the lwIP TCP/IP stack. + * + * Author: Adam Dunkels <adam@sics.se> + * + */ + +/* @todo Check the use of '(struct udp_pcb).chksum_len_rx'! + */ + +#include "lwip/opt.h" + +#if LWIP_UDP /* don't build if not configured for use in lwipopts.h */ + +#include "lwip/udp.h" +#include "lwip/def.h" +#include "lwip/memp.h" +#include "lwip/inet_chksum.h" +#include "lwip/ip_addr.h" +#include "lwip/ip6.h" +#include "lwip/ip6_addr.h" +#include "lwip/netif.h" +#include "lwip/icmp.h" +#include "lwip/icmp6.h" +#include "lwip/stats.h" +#include "lwip/snmp.h" +#include "lwip/dhcp.h" + +#include <string.h> + +#ifndef UDP_LOCAL_PORT_RANGE_START +/* From http://www.iana.org/assignments/port-numbers: + "The Dynamic and/or Private Ports are those from 49152 through 65535" */ +#define UDP_LOCAL_PORT_RANGE_START 0xc000 +#define UDP_LOCAL_PORT_RANGE_END 0xffff +#define UDP_ENSURE_LOCAL_PORT_RANGE(port) ((u16_t)(((port) & (u16_t)~UDP_LOCAL_PORT_RANGE_START) + UDP_LOCAL_PORT_RANGE_START)) +#endif + +/* last local UDP port */ +static u16_t udp_port = UDP_LOCAL_PORT_RANGE_START; + +/* The list of UDP PCBs */ +/* exported in udp.h (was static) */ +struct udp_pcb *udp_pcbs; + +/** + * Initialize this module. + */ +void +udp_init(void) +{ +#ifdef LWIP_RAND + udp_port = UDP_ENSURE_LOCAL_PORT_RANGE(LWIP_RAND()); +#endif /* LWIP_RAND */ +} + +/** + * Allocate a new local UDP port. + * + * @return a new (free) local UDP port number + */ +static u16_t +udp_new_port(void) +{ + u16_t n = 0; + struct udp_pcb *pcb; + +again: + if (udp_port++ == UDP_LOCAL_PORT_RANGE_END) { + udp_port = UDP_LOCAL_PORT_RANGE_START; + } + /* Check all PCBs. */ + for (pcb = udp_pcbs; pcb != NULL; pcb = pcb->next) { + if (pcb->local_port == udp_port) { + if (++n > (UDP_LOCAL_PORT_RANGE_END - UDP_LOCAL_PORT_RANGE_START)) { + return 0; + } + goto again; + } + } + return udp_port; +} + +/** Common code to see if the current input packet matches the pcb + * (current input packet is accessed via ip(4/6)_current_* macros) + * + * @param pcb pcb to check + * @param inp network interface on which the datagram was received (only used for IPv4) + * @param broadcast 1 if his is an IPv4 broadcast (global or subnet-only), 0 otherwise (only used for IPv4) + * @return 1 on match, 0 otherwise + */ +static u8_t +udp_input_local_match(struct udp_pcb *pcb, struct netif *inp, u8_t broadcast) +{ + LWIP_UNUSED_ARG(inp); /* in IPv6 only case */ + LWIP_UNUSED_ARG(broadcast); /* in IPv6 only case */ + + LWIP_ASSERT("udp_input_local_match: invalid pcb", pcb != NULL); + LWIP_ASSERT("udp_input_local_match: invalid netif", inp != NULL); + + /* check if PCB is bound to specific netif */ + if ((pcb->netif_idx != NETIF_NO_INDEX) && + (pcb->netif_idx != netif_get_index(ip_data.current_input_netif))) { + return 0; + } + + /* Dual-stack: PCBs listening to any IP type also listen to any IP address */ + if (IP_IS_ANY_TYPE_VAL(pcb->local_ip)) { +#if LWIP_IPV4 && IP_SOF_BROADCAST_RECV + if ((broadcast != 0) && !ip_get_option(pcb, SOF_BROADCAST)) { + return 0; + } +#endif /* LWIP_IPV4 && IP_SOF_BROADCAST_RECV */ + return 1; + } + + /* Only need to check PCB if incoming IP version matches PCB IP version */ + if (IP_ADDR_PCB_VERSION_MATCH_EXACT(pcb, ip_current_dest_addr())) { +#if LWIP_IPV4 + /* Special case: IPv4 broadcast: all or broadcasts in my subnet + * Note: broadcast variable can only be 1 if it is an IPv4 broadcast */ + if (broadcast != 0) { +#if IP_SOF_BROADCAST_RECV + if (ip_get_option(pcb, SOF_BROADCAST)) +#endif /* IP_SOF_BROADCAST_RECV */ + { + if (ip4_addr_isany(ip_2_ip4(&pcb->local_ip)) || + ((ip4_current_dest_addr()->addr == IPADDR_BROADCAST)) || + ip4_addr_netcmp(ip_2_ip4(&pcb->local_ip), ip4_current_dest_addr(), netif_ip4_netmask(inp))) { + return 1; + } + } + } else +#endif /* LWIP_IPV4 */ + /* Handle IPv4 and IPv6: all or exact match */ + if (ip_addr_isany(&pcb->local_ip) || ip_addr_cmp(&pcb->local_ip, ip_current_dest_addr())) { + return 1; + } + } + + return 0; +} + +/** + * Process an incoming UDP datagram. + * + * Given an incoming UDP datagram (as a chain of pbufs) this function + * finds a corresponding UDP PCB and hands over the pbuf to the pcbs + * recv function. If no pcb is found or the datagram is incorrect, the + * pbuf is freed. + * + * @param p pbuf to be demultiplexed to a UDP PCB (p->payload pointing to the UDP header) + * @param inp network interface on which the datagram was received. + * + */ +void +udp_input(struct pbuf *p, struct netif *inp) +{ + struct udp_hdr *udphdr; + struct udp_pcb *pcb, *prev; + struct udp_pcb *uncon_pcb; + u16_t src, dest; + u8_t broadcast; + u8_t for_us = 0; + + LWIP_UNUSED_ARG(inp); + + LWIP_ASSERT_CORE_LOCKED(); + + LWIP_ASSERT("udp_input: invalid pbuf", p != NULL); + LWIP_ASSERT("udp_input: invalid netif", inp != NULL); + + PERF_START; + + UDP_STATS_INC(udp.recv); + + /* Check minimum length (UDP header) */ + if (p->len < UDP_HLEN) { + /* drop short packets */ + LWIP_DEBUGF(UDP_DEBUG, + ("udp_input: short UDP datagram (%"U16_F" bytes) discarded\n", p->tot_len)); + UDP_STATS_INC(udp.lenerr); + UDP_STATS_INC(udp.drop); + MIB2_STATS_INC(mib2.udpinerrors); + pbuf_free(p); + goto end; + } + + udphdr = (struct udp_hdr *)p->payload; + + /* is broadcast packet ? */ + broadcast = ip_addr_isbroadcast(ip_current_dest_addr(), ip_current_netif()); + + LWIP_DEBUGF(UDP_DEBUG, ("udp_input: received datagram of length %"U16_F"\n", p->tot_len)); + + /* convert src and dest ports to host byte order */ + src = lwip_ntohs(udphdr->src); + dest = lwip_ntohs(udphdr->dest); + + udp_debug_print(udphdr); + + /* print the UDP source and destination */ + LWIP_DEBUGF(UDP_DEBUG, ("udp (")); + ip_addr_debug_print_val(UDP_DEBUG, *ip_current_dest_addr()); + LWIP_DEBUGF(UDP_DEBUG, (", %"U16_F") <-- (", lwip_ntohs(udphdr->dest))); + ip_addr_debug_print_val(UDP_DEBUG, *ip_current_src_addr()); + LWIP_DEBUGF(UDP_DEBUG, (", %"U16_F")\n", lwip_ntohs(udphdr->src))); + + pcb = NULL; + prev = NULL; + uncon_pcb = NULL; + /* Iterate through the UDP pcb list for a matching pcb. + * 'Perfect match' pcbs (connected to the remote port & ip address) are + * preferred. If no perfect match is found, the first unconnected pcb that + * matches the local port and ip address gets the datagram. */ + for (pcb = udp_pcbs; pcb != NULL; pcb = pcb->next) { + /* print the PCB local and remote address */ + LWIP_DEBUGF(UDP_DEBUG, ("pcb (")); + ip_addr_debug_print_val(UDP_DEBUG, pcb->local_ip); + LWIP_DEBUGF(UDP_DEBUG, (", %"U16_F") <-- (", pcb->local_port)); + ip_addr_debug_print_val(UDP_DEBUG, pcb->remote_ip); + LWIP_DEBUGF(UDP_DEBUG, (", %"U16_F")\n", pcb->remote_port)); + + /* compare PCB local addr+port to UDP destination addr+port */ + if ((pcb->local_port == dest) && + (udp_input_local_match(pcb, inp, broadcast) != 0)) { + if ((pcb->flags & UDP_FLAGS_CONNECTED) == 0) { + if (uncon_pcb == NULL) { + /* the first unconnected matching PCB */ + uncon_pcb = pcb; +#if LWIP_IPV4 + } else if (broadcast && ip4_current_dest_addr()->addr == IPADDR_BROADCAST) { + /* global broadcast address (only valid for IPv4; match was checked before) */ + if (!IP_IS_V4_VAL(uncon_pcb->local_ip) || !ip4_addr_cmp(ip_2_ip4(&uncon_pcb->local_ip), netif_ip4_addr(inp))) { + /* uncon_pcb does not match the input netif, check this pcb */ + if (IP_IS_V4_VAL(pcb->local_ip) && ip4_addr_cmp(ip_2_ip4(&pcb->local_ip), netif_ip4_addr(inp))) { + /* better match */ + uncon_pcb = pcb; + } + } +#endif /* LWIP_IPV4 */ + } +#if SO_REUSE + else if (!ip_addr_isany(&pcb->local_ip)) { + /* prefer specific IPs over catch-all */ + uncon_pcb = pcb; + } +#endif /* SO_REUSE */ + } + + /* compare PCB remote addr+port to UDP source addr+port */ + if ((pcb->remote_port == src) && + (ip_addr_isany_val(pcb->remote_ip) || + ip_addr_cmp(&pcb->remote_ip, ip_current_src_addr()))) { + /* the first fully matching PCB */ + if (prev != NULL) { + /* move the pcb to the front of udp_pcbs so that is + found faster next time */ + prev->next = pcb->next; + pcb->next = udp_pcbs; + udp_pcbs = pcb; + } else { + UDP_STATS_INC(udp.cachehit); + } + break; + } + } + + prev = pcb; + } + /* no fully matching pcb found? then look for an unconnected pcb */ + if (pcb == NULL) { + pcb = uncon_pcb; + } + + /* Check checksum if this is a match or if it was directed at us. */ + if (pcb != NULL) { + for_us = 1; + } else { +#if LWIP_IPV6 + if (ip_current_is_v6()) { + for_us = netif_get_ip6_addr_match(inp, ip6_current_dest_addr()) >= 0; + } +#endif /* LWIP_IPV6 */ +#if LWIP_IPV4 + if (!ip_current_is_v6()) { + for_us = ip4_addr_cmp(netif_ip4_addr(inp), ip4_current_dest_addr()); + } +#endif /* LWIP_IPV4 */ + } + + if (for_us) { + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, ("udp_input: calculating checksum\n")); +#if CHECKSUM_CHECK_UDP + IF__NETIF_CHECKSUM_ENABLED(inp, NETIF_CHECKSUM_CHECK_UDP) { +#if LWIP_UDPLITE + if (ip_current_header_proto() == IP_PROTO_UDPLITE) { + /* Do the UDP Lite checksum */ + u16_t chklen = lwip_ntohs(udphdr->len); + if (chklen < sizeof(struct udp_hdr)) { + if (chklen == 0) { + /* For UDP-Lite, checksum length of 0 means checksum + over the complete packet (See RFC 3828 chap. 3.1) */ + chklen = p->tot_len; + } else { + /* At least the UDP-Lite header must be covered by the + checksum! (Again, see RFC 3828 chap. 3.1) */ + goto chkerr; + } + } + if (ip_chksum_pseudo_partial(p, IP_PROTO_UDPLITE, + p->tot_len, chklen, + ip_current_src_addr(), ip_current_dest_addr()) != 0) { + goto chkerr; + } + } else +#endif /* LWIP_UDPLITE */ + { + if (udphdr->chksum != 0) { + if (ip_chksum_pseudo(p, IP_PROTO_UDP, p->tot_len, + ip_current_src_addr(), + ip_current_dest_addr()) != 0) { + goto chkerr; + } + } + } + } +#endif /* CHECKSUM_CHECK_UDP */ + if (pbuf_remove_header(p, UDP_HLEN)) { + /* Can we cope with this failing? Just assert for now */ + LWIP_ASSERT("pbuf_remove_header failed\n", 0); + UDP_STATS_INC(udp.drop); + MIB2_STATS_INC(mib2.udpinerrors); + pbuf_free(p); + goto end; + } + + if (pcb != NULL) { + MIB2_STATS_INC(mib2.udpindatagrams); +#if SO_REUSE && SO_REUSE_RXTOALL + if (ip_get_option(pcb, SOF_REUSEADDR) && + (broadcast || ip_addr_ismulticast(ip_current_dest_addr()))) { + /* pass broadcast- or multicast packets to all multicast pcbs + if SOF_REUSEADDR is set on the first match */ + struct udp_pcb *mpcb; + for (mpcb = udp_pcbs; mpcb != NULL; mpcb = mpcb->next) { + if (mpcb != pcb) { + /* compare PCB local addr+port to UDP destination addr+port */ + if ((mpcb->local_port == dest) && + (udp_input_local_match(mpcb, inp, broadcast) != 0)) { + /* pass a copy of the packet to all local matches */ + if (mpcb->recv != NULL) { + struct pbuf *q; + q = pbuf_clone(PBUF_RAW, PBUF_POOL, p); + if (q != NULL) { + mpcb->recv(mpcb->recv_arg, mpcb, q, ip_current_src_addr(), src); + } + } + } + } + } + } +#endif /* SO_REUSE && SO_REUSE_RXTOALL */ + /* callback */ + if (pcb->recv != NULL) { + /* now the recv function is responsible for freeing p */ + pcb->recv(pcb->recv_arg, pcb, p, ip_current_src_addr(), src); + } else { + /* no recv function registered? then we have to free the pbuf! */ + pbuf_free(p); + goto end; + } + } else { + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, ("udp_input: not for us.\n")); + +#if LWIP_ICMP || LWIP_ICMP6 + /* No match was found, send ICMP destination port unreachable unless + destination address was broadcast/multicast. */ + if (!broadcast && !ip_addr_ismulticast(ip_current_dest_addr())) { + /* move payload pointer back to ip header */ + pbuf_header_force(p, (s16_t)(ip_current_header_tot_len() + UDP_HLEN)); + icmp_port_unreach(ip_current_is_v6(), p); + } +#endif /* LWIP_ICMP || LWIP_ICMP6 */ + UDP_STATS_INC(udp.proterr); + UDP_STATS_INC(udp.drop); + MIB2_STATS_INC(mib2.udpnoports); + pbuf_free(p); + } + } else { + pbuf_free(p); + } +end: + PERF_STOP("udp_input"); + return; +#if CHECKSUM_CHECK_UDP +chkerr: + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, + ("udp_input: UDP (or UDP Lite) datagram discarded due to failing checksum\n")); + UDP_STATS_INC(udp.chkerr); + UDP_STATS_INC(udp.drop); + MIB2_STATS_INC(mib2.udpinerrors); + pbuf_free(p); + PERF_STOP("udp_input"); +#endif /* CHECKSUM_CHECK_UDP */ +} + +/** + * @ingroup udp_raw + * Sends the pbuf p using UDP. The pbuf is not deallocated. + * + * + * @param pcb UDP PCB used to send the data. + * @param p chain of pbuf's to be sent. + * + * The datagram will be sent to the current remote_ip & remote_port + * stored in pcb. If the pcb is not bound to a port, it will + * automatically be bound to a random port. + * + * @return lwIP error code. + * - ERR_OK. Successful. No error occurred. + * - ERR_MEM. Out of memory. + * - ERR_RTE. Could not find route to destination address. + * - ERR_VAL. No PCB or PCB is dual-stack + * - More errors could be returned by lower protocol layers. + * + * @see udp_disconnect() udp_sendto() + */ +err_t +udp_send(struct udp_pcb *pcb, struct pbuf *p) +{ + LWIP_ERROR("udp_send: invalid pcb", pcb != NULL, return ERR_ARG); + LWIP_ERROR("udp_send: invalid pbuf", p != NULL, return ERR_ARG); + + if (IP_IS_ANY_TYPE_VAL(pcb->remote_ip)) { + return ERR_VAL; + } + + /* send to the packet using remote ip and port stored in the pcb */ + return udp_sendto(pcb, p, &pcb->remote_ip, pcb->remote_port); +} + +#if LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_UDP +/** @ingroup udp_raw + * Same as udp_send() but with checksum + */ +err_t +udp_send_chksum(struct udp_pcb *pcb, struct pbuf *p, + u8_t have_chksum, u16_t chksum) +{ + LWIP_ERROR("udp_send_chksum: invalid pcb", pcb != NULL, return ERR_ARG); + LWIP_ERROR("udp_send_chksum: invalid pbuf", p != NULL, return ERR_ARG); + + if (IP_IS_ANY_TYPE_VAL(pcb->remote_ip)) { + return ERR_VAL; + } + + /* send to the packet using remote ip and port stored in the pcb */ + return udp_sendto_chksum(pcb, p, &pcb->remote_ip, pcb->remote_port, + have_chksum, chksum); +} +#endif /* LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_UDP */ + +/** + * @ingroup udp_raw + * Send data to a specified address using UDP. + * + * @param pcb UDP PCB used to send the data. + * @param p chain of pbuf's to be sent. + * @param dst_ip Destination IP address. + * @param dst_port Destination UDP port. + * + * dst_ip & dst_port are expected to be in the same byte order as in the pcb. + * + * If the PCB already has a remote address association, it will + * be restored after the data is sent. + * + * @return lwIP error code (@see udp_send for possible error codes) + * + * @see udp_disconnect() udp_send() + */ +err_t +udp_sendto(struct udp_pcb *pcb, struct pbuf *p, + const ip_addr_t *dst_ip, u16_t dst_port) +{ +#if LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_UDP + return udp_sendto_chksum(pcb, p, dst_ip, dst_port, 0, 0); +} + +/** @ingroup udp_raw + * Same as udp_sendto(), but with checksum */ +err_t +udp_sendto_chksum(struct udp_pcb *pcb, struct pbuf *p, const ip_addr_t *dst_ip, + u16_t dst_port, u8_t have_chksum, u16_t chksum) +{ +#endif /* LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_UDP */ + struct netif *netif; + + LWIP_ERROR("udp_sendto: invalid pcb", pcb != NULL, return ERR_ARG); + LWIP_ERROR("udp_sendto: invalid pbuf", p != NULL, return ERR_ARG); + LWIP_ERROR("udp_sendto: invalid dst_ip", dst_ip != NULL, return ERR_ARG); + + if (!IP_ADDR_PCB_VERSION_MATCH(pcb, dst_ip)) { + return ERR_VAL; + } + + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, ("udp_send\n")); + + if (pcb->netif_idx != NETIF_NO_INDEX) { + netif = netif_get_by_index(pcb->netif_idx); + } else { +#if LWIP_MULTICAST_TX_OPTIONS + netif = NULL; + if (ip_addr_ismulticast(dst_ip)) { + /* For IPv6, the interface to use for packets with a multicast destination + * is specified using an interface index. The same approach may be used for + * IPv4 as well, in which case it overrides the IPv4 multicast override + * address below. Here we have to look up the netif by going through the + * list, but by doing so we skip a route lookup. If the interface index has + * gone stale, we fall through and do the regular route lookup after all. */ + if (pcb->mcast_ifindex != NETIF_NO_INDEX) { + netif = netif_get_by_index(pcb->mcast_ifindex); + } +#if LWIP_IPV4 + else +#if LWIP_IPV6 + if (IP_IS_V4(dst_ip)) +#endif /* LWIP_IPV6 */ + { + /* IPv4 does not use source-based routing by default, so we use an + administratively selected interface for multicast by default. + However, this can be overridden by setting an interface address + in pcb->mcast_ip4 that is used for routing. If this routing lookup + fails, we try regular routing as though no override was set. */ + if (!ip4_addr_isany_val(pcb->mcast_ip4) && + !ip4_addr_cmp(&pcb->mcast_ip4, IP4_ADDR_BROADCAST)) { + netif = ip4_route_src(ip_2_ip4(&pcb->local_ip), &pcb->mcast_ip4); + } + } +#endif /* LWIP_IPV4 */ + } + + if (netif == NULL) +#endif /* LWIP_MULTICAST_TX_OPTIONS */ + { + /* find the outgoing network interface for this packet */ + netif = ip_route(&pcb->local_ip, dst_ip); + } + } + + /* no outgoing network interface could be found? */ + if (netif == NULL) { + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("udp_send: No route to ")); + ip_addr_debug_print(UDP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, dst_ip); + LWIP_DEBUGF(UDP_DEBUG, ("\n")); + UDP_STATS_INC(udp.rterr); + return ERR_RTE; + } +#if LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_UDP + return udp_sendto_if_chksum(pcb, p, dst_ip, dst_port, netif, have_chksum, chksum); +#else /* LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_UDP */ + return udp_sendto_if(pcb, p, dst_ip, dst_port, netif); +#endif /* LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_UDP */ +} + +/** + * @ingroup udp_raw + * Send data to a specified address using UDP. + * The netif used for sending can be specified. + * + * This function exists mainly for DHCP, to be able to send UDP packets + * on a netif that is still down. + * + * @param pcb UDP PCB used to send the data. + * @param p chain of pbuf's to be sent. + * @param dst_ip Destination IP address. + * @param dst_port Destination UDP port. + * @param netif the netif used for sending. + * + * dst_ip & dst_port are expected to be in the same byte order as in the pcb. + * + * @return lwIP error code (@see udp_send for possible error codes) + * + * @see udp_disconnect() udp_send() + */ +err_t +udp_sendto_if(struct udp_pcb *pcb, struct pbuf *p, + const ip_addr_t *dst_ip, u16_t dst_port, struct netif *netif) +{ +#if LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_UDP + return udp_sendto_if_chksum(pcb, p, dst_ip, dst_port, netif, 0, 0); +} + +/** Same as udp_sendto_if(), but with checksum */ +err_t +udp_sendto_if_chksum(struct udp_pcb *pcb, struct pbuf *p, const ip_addr_t *dst_ip, + u16_t dst_port, struct netif *netif, u8_t have_chksum, + u16_t chksum) +{ +#endif /* LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_UDP */ + const ip_addr_t *src_ip; + + LWIP_ERROR("udp_sendto_if: invalid pcb", pcb != NULL, return ERR_ARG); + LWIP_ERROR("udp_sendto_if: invalid pbuf", p != NULL, return ERR_ARG); + LWIP_ERROR("udp_sendto_if: invalid dst_ip", dst_ip != NULL, return ERR_ARG); + LWIP_ERROR("udp_sendto_if: invalid netif", netif != NULL, return ERR_ARG); + + if (!IP_ADDR_PCB_VERSION_MATCH(pcb, dst_ip)) { + return ERR_VAL; + } + + /* PCB local address is IP_ANY_ADDR or multicast? */ +#if LWIP_IPV6 + if (IP_IS_V6(dst_ip)) { + if (ip6_addr_isany(ip_2_ip6(&pcb->local_ip)) || + ip6_addr_ismulticast(ip_2_ip6(&pcb->local_ip))) { + src_ip = ip6_select_source_address(netif, ip_2_ip6(dst_ip)); + if (src_ip == NULL) { + /* No suitable source address was found. */ + return ERR_RTE; + } + } else { + /* use UDP PCB local IPv6 address as source address, if still valid. */ + if (netif_get_ip6_addr_match(netif, ip_2_ip6(&pcb->local_ip)) < 0) { + /* Address isn't valid anymore. */ + return ERR_RTE; + } + src_ip = &pcb->local_ip; + } + } +#endif /* LWIP_IPV6 */ +#if LWIP_IPV4 && LWIP_IPV6 + else +#endif /* LWIP_IPV4 && LWIP_IPV6 */ +#if LWIP_IPV4 + if (ip4_addr_isany(ip_2_ip4(&pcb->local_ip)) || + ip4_addr_ismulticast(ip_2_ip4(&pcb->local_ip))) { + /* if the local_ip is any or multicast + * use the outgoing network interface IP address as source address */ + src_ip = netif_ip_addr4(netif); + } else { + /* check if UDP PCB local IP address is correct + * this could be an old address if netif->ip_addr has changed */ + if (!ip4_addr_cmp(ip_2_ip4(&(pcb->local_ip)), netif_ip4_addr(netif))) { + /* local_ip doesn't match, drop the packet */ + return ERR_RTE; + } + /* use UDP PCB local IP address as source address */ + src_ip = &pcb->local_ip; + } +#endif /* LWIP_IPV4 */ +#if LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_UDP + return udp_sendto_if_src_chksum(pcb, p, dst_ip, dst_port, netif, have_chksum, chksum, src_ip); +#else /* LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_UDP */ + return udp_sendto_if_src(pcb, p, dst_ip, dst_port, netif, src_ip); +#endif /* LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_UDP */ +} + +/** @ingroup udp_raw + * Same as @ref udp_sendto_if, but with source address */ +err_t +udp_sendto_if_src(struct udp_pcb *pcb, struct pbuf *p, + const ip_addr_t *dst_ip, u16_t dst_port, struct netif *netif, const ip_addr_t *src_ip) +{ +#if LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_UDP + return udp_sendto_if_src_chksum(pcb, p, dst_ip, dst_port, netif, 0, 0, src_ip); +} + +/** Same as udp_sendto_if_src(), but with checksum */ +err_t +udp_sendto_if_src_chksum(struct udp_pcb *pcb, struct pbuf *p, const ip_addr_t *dst_ip, + u16_t dst_port, struct netif *netif, u8_t have_chksum, + u16_t chksum, const ip_addr_t *src_ip) +{ +#endif /* LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_UDP */ + struct udp_hdr *udphdr; + err_t err; + struct pbuf *q; /* q will be sent down the stack */ + u8_t ip_proto; + u8_t ttl; + + LWIP_ASSERT_CORE_LOCKED(); + + LWIP_ERROR("udp_sendto_if_src: invalid pcb", pcb != NULL, return ERR_ARG); + LWIP_ERROR("udp_sendto_if_src: invalid pbuf", p != NULL, return ERR_ARG); + LWIP_ERROR("udp_sendto_if_src: invalid dst_ip", dst_ip != NULL, return ERR_ARG); + LWIP_ERROR("udp_sendto_if_src: invalid src_ip", src_ip != NULL, return ERR_ARG); + LWIP_ERROR("udp_sendto_if_src: invalid netif", netif != NULL, return ERR_ARG); + + if (!IP_ADDR_PCB_VERSION_MATCH(pcb, src_ip) || + !IP_ADDR_PCB_VERSION_MATCH(pcb, dst_ip)) { + return ERR_VAL; + } + +#if LWIP_IPV4 && IP_SOF_BROADCAST + /* broadcast filter? */ + if (!ip_get_option(pcb, SOF_BROADCAST) && +#if LWIP_IPV6 + IP_IS_V4(dst_ip) && +#endif /* LWIP_IPV6 */ + ip_addr_isbroadcast(dst_ip, netif)) { + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, + ("udp_sendto_if: SOF_BROADCAST not enabled on pcb %p\n", (void *)pcb)); + return ERR_VAL; + } +#endif /* LWIP_IPV4 && IP_SOF_BROADCAST */ + + /* if the PCB is not yet bound to a port, bind it here */ + if (pcb->local_port == 0) { + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, ("udp_send: not yet bound to a port, binding now\n")); + err = udp_bind(pcb, &pcb->local_ip, pcb->local_port); + if (err != ERR_OK) { + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("udp_send: forced port bind failed\n")); + return err; + } + } + + /* packet too large to add a UDP header without causing an overflow? */ + if ((u16_t)(p->tot_len + UDP_HLEN) < p->tot_len) { + return ERR_MEM; + } + /* not enough space to add an UDP header to first pbuf in given p chain? */ + if (pbuf_add_header(p, UDP_HLEN)) { + /* allocate header in a separate new pbuf */ + q = pbuf_alloc(PBUF_IP, UDP_HLEN, PBUF_RAM); + /* new header pbuf could not be allocated? */ + if (q == NULL) { + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("udp_send: could not allocate header\n")); + return ERR_MEM; + } + if (p->tot_len != 0) { + /* chain header q in front of given pbuf p (only if p contains data) */ + pbuf_chain(q, p); + } + /* first pbuf q points to header pbuf */ + LWIP_DEBUGF(UDP_DEBUG, + ("udp_send: added header pbuf %p before given pbuf %p\n", (void *)q, (void *)p)); + } else { + /* adding space for header within p succeeded */ + /* first pbuf q equals given pbuf */ + q = p; + LWIP_DEBUGF(UDP_DEBUG, ("udp_send: added header in given pbuf %p\n", (void *)p)); + } + LWIP_ASSERT("check that first pbuf can hold struct udp_hdr", + (q->len >= sizeof(struct udp_hdr))); + /* q now represents the packet to be sent */ + udphdr = (struct udp_hdr *)q->payload; + udphdr->src = lwip_htons(pcb->local_port); + udphdr->dest = lwip_htons(dst_port); + /* in UDP, 0 checksum means 'no checksum' */ + udphdr->chksum = 0x0000; + + /* Multicast Loop? */ +#if LWIP_MULTICAST_TX_OPTIONS + if (((pcb->flags & UDP_FLAGS_MULTICAST_LOOP) != 0) && ip_addr_ismulticast(dst_ip)) { + q->flags |= PBUF_FLAG_MCASTLOOP; + } +#endif /* LWIP_MULTICAST_TX_OPTIONS */ + + LWIP_DEBUGF(UDP_DEBUG, ("udp_send: sending datagram of length %"U16_F"\n", q->tot_len)); + +#if LWIP_UDPLITE + /* UDP Lite protocol? */ + if (pcb->flags & UDP_FLAGS_UDPLITE) { + u16_t chklen, chklen_hdr; + LWIP_DEBUGF(UDP_DEBUG, ("udp_send: UDP LITE packet length %"U16_F"\n", q->tot_len)); + /* set UDP message length in UDP header */ + chklen_hdr = chklen = pcb->chksum_len_tx; + if ((chklen < sizeof(struct udp_hdr)) || (chklen > q->tot_len)) { + if (chklen != 0) { + LWIP_DEBUGF(UDP_DEBUG, ("udp_send: UDP LITE pcb->chksum_len is illegal: %"U16_F"\n", chklen)); + } + /* For UDP-Lite, checksum length of 0 means checksum + over the complete packet. (See RFC 3828 chap. 3.1) + At least the UDP-Lite header must be covered by the + checksum, therefore, if chksum_len has an illegal + value, we generate the checksum over the complete + packet to be safe. */ + chklen_hdr = 0; + chklen = q->tot_len; + } + udphdr->len = lwip_htons(chklen_hdr); + /* calculate checksum */ +#if CHECKSUM_GEN_UDP + IF__NETIF_CHECKSUM_ENABLED(netif, NETIF_CHECKSUM_GEN_UDP) { +#if LWIP_CHECKSUM_ON_COPY + if (have_chksum) { + chklen = UDP_HLEN; + } +#endif /* LWIP_CHECKSUM_ON_COPY */ + udphdr->chksum = ip_chksum_pseudo_partial(q, IP_PROTO_UDPLITE, + q->tot_len, chklen, src_ip, dst_ip); +#if LWIP_CHECKSUM_ON_COPY + if (have_chksum) { + u32_t acc; + acc = udphdr->chksum + (u16_t)~(chksum); + udphdr->chksum = FOLD_U32T(acc); + } +#endif /* LWIP_CHECKSUM_ON_COPY */ + + /* chksum zero must become 0xffff, as zero means 'no checksum' */ + if (udphdr->chksum == 0x0000) { + udphdr->chksum = 0xffff; + } + } +#endif /* CHECKSUM_GEN_UDP */ + + ip_proto = IP_PROTO_UDPLITE; + } else +#endif /* LWIP_UDPLITE */ + { /* UDP */ + LWIP_DEBUGF(UDP_DEBUG, ("udp_send: UDP packet length %"U16_F"\n", q->tot_len)); + udphdr->len = lwip_htons(q->tot_len); + /* calculate checksum */ +#if CHECKSUM_GEN_UDP + IF__NETIF_CHECKSUM_ENABLED(netif, NETIF_CHECKSUM_GEN_UDP) { + /* Checksum is mandatory over IPv6. */ + if (IP_IS_V6(dst_ip) || (pcb->flags & UDP_FLAGS_NOCHKSUM) == 0) { + u16_t udpchksum; +#if LWIP_CHECKSUM_ON_COPY + if (have_chksum) { + u32_t acc; + udpchksum = ip_chksum_pseudo_partial(q, IP_PROTO_UDP, + q->tot_len, UDP_HLEN, src_ip, dst_ip); + acc = udpchksum + (u16_t)~(chksum); + udpchksum = FOLD_U32T(acc); + } else +#endif /* LWIP_CHECKSUM_ON_COPY */ + { + udpchksum = ip_chksum_pseudo(q, IP_PROTO_UDP, q->tot_len, + src_ip, dst_ip); + } + + /* chksum zero must become 0xffff, as zero means 'no checksum' */ + if (udpchksum == 0x0000) { + udpchksum = 0xffff; + } + udphdr->chksum = udpchksum; + } + } +#endif /* CHECKSUM_GEN_UDP */ + ip_proto = IP_PROTO_UDP; + } + + /* Determine TTL to use */ +#if LWIP_MULTICAST_TX_OPTIONS + ttl = (ip_addr_ismulticast(dst_ip) ? udp_get_multicast_ttl(pcb) : pcb->ttl); +#else /* LWIP_MULTICAST_TX_OPTIONS */ + ttl = pcb->ttl; +#endif /* LWIP_MULTICAST_TX_OPTIONS */ + + LWIP_DEBUGF(UDP_DEBUG, ("udp_send: UDP checksum 0x%04"X16_F"\n", udphdr->chksum)); + LWIP_DEBUGF(UDP_DEBUG, ("udp_send: ip_output_if (,,,,0x%02"X16_F",)\n", (u16_t)ip_proto)); + /* output to IP */ + NETIF_SET_HINTS(netif, &(pcb->netif_hints)); + err = ip_output_if_src(q, src_ip, dst_ip, ttl, pcb->tos, ip_proto, netif); + NETIF_RESET_HINTS(netif); + + /* @todo: must this be increased even if error occurred? */ + MIB2_STATS_INC(mib2.udpoutdatagrams); + + /* did we chain a separate header pbuf earlier? */ + if (q != p) { + /* free the header pbuf */ + pbuf_free(q); + q = NULL; + /* p is still referenced by the caller, and will live on */ + } + + UDP_STATS_INC(udp.xmit); + return err; +} + +/** + * @ingroup udp_raw + * Bind an UDP PCB. + * + * @param pcb UDP PCB to be bound with a local address ipaddr and port. + * @param ipaddr local IP address to bind with. Use IP_ANY_TYPE to + * bind to all local interfaces. + * @param port local UDP port to bind with. Use 0 to automatically bind + * to a random port between UDP_LOCAL_PORT_RANGE_START and + * UDP_LOCAL_PORT_RANGE_END. + * + * ipaddr & port are expected to be in the same byte order as in the pcb. + * + * @return lwIP error code. + * - ERR_OK. Successful. No error occurred. + * - ERR_USE. The specified ipaddr and port are already bound to by + * another UDP PCB. + * + * @see udp_disconnect() + */ +err_t +udp_bind(struct udp_pcb *pcb, const ip_addr_t *ipaddr, u16_t port) +{ + struct udp_pcb *ipcb; + u8_t rebind; +#if LWIP_IPV6 && LWIP_IPV6_SCOPES + ip_addr_t zoned_ipaddr; +#endif /* LWIP_IPV6 && LWIP_IPV6_SCOPES */ + + LWIP_ASSERT_CORE_LOCKED(); + +#if LWIP_IPV4 + /* Don't propagate NULL pointer (IPv4 ANY) to subsequent functions */ + if (ipaddr == NULL) { + ipaddr = IP4_ADDR_ANY; + } +#else /* LWIP_IPV4 */ + LWIP_ERROR("udp_bind: invalid ipaddr", ipaddr != NULL, return ERR_ARG); +#endif /* LWIP_IPV4 */ + + LWIP_ERROR("udp_bind: invalid pcb", pcb != NULL, return ERR_ARG); + + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, ("udp_bind(ipaddr = ")); + ip_addr_debug_print(UDP_DEBUG | LWIP_DBG_TRACE, ipaddr); + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, (", port = %"U16_F")\n", port)); + + rebind = 0; + /* Check for double bind and rebind of the same pcb */ + for (ipcb = udp_pcbs; ipcb != NULL; ipcb = ipcb->next) { + /* is this UDP PCB already on active list? */ + if (pcb == ipcb) { + rebind = 1; + break; + } + } + +#if LWIP_IPV6 && LWIP_IPV6_SCOPES + /* If the given IP address should have a zone but doesn't, assign one now. + * This is legacy support: scope-aware callers should always provide properly + * zoned source addresses. Do the zone selection before the address-in-use + * check below; as such we have to make a temporary copy of the address. */ + if (IP_IS_V6(ipaddr) && ip6_addr_lacks_zone(ip_2_ip6(ipaddr), IP6_UNKNOWN)) { + ip_addr_copy(zoned_ipaddr, *ipaddr); + ip6_addr_select_zone(ip_2_ip6(&zoned_ipaddr), ip_2_ip6(&zoned_ipaddr)); + ipaddr = &zoned_ipaddr; + } +#endif /* LWIP_IPV6 && LWIP_IPV6_SCOPES */ + + /* no port specified? */ + if (port == 0) { + port = udp_new_port(); + if (port == 0) { + /* no more ports available in local range */ + LWIP_DEBUGF(UDP_DEBUG, ("udp_bind: out of free UDP ports\n")); + return ERR_USE; + } + } else { + for (ipcb = udp_pcbs; ipcb != NULL; ipcb = ipcb->next) { + if (pcb != ipcb) { + /* By default, we don't allow to bind to a port that any other udp + PCB is already bound to, unless *all* PCBs with that port have tha + REUSEADDR flag set. */ +#if SO_REUSE + if (!ip_get_option(pcb, SOF_REUSEADDR) || + !ip_get_option(ipcb, SOF_REUSEADDR)) +#endif /* SO_REUSE */ + { + /* port matches that of PCB in list and REUSEADDR not set -> reject */ + if ((ipcb->local_port == port) && + /* IP address matches or any IP used? */ + (ip_addr_cmp(&ipcb->local_ip, ipaddr) || ip_addr_isany(ipaddr) || + ip_addr_isany(&ipcb->local_ip))) { + /* other PCB already binds to this local IP and port */ + LWIP_DEBUGF(UDP_DEBUG, + ("udp_bind: local port %"U16_F" already bound by another pcb\n", port)); + return ERR_USE; + } + } + } + } + } + + ip_addr_set_ipaddr(&pcb->local_ip, ipaddr); + + pcb->local_port = port; + mib2_udp_bind(pcb); + /* pcb not active yet? */ + if (rebind == 0) { + /* place the PCB on the active list if not already there */ + pcb->next = udp_pcbs; + udp_pcbs = pcb; + } + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("udp_bind: bound to ")); + ip_addr_debug_print_val(UDP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, pcb->local_ip); + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, (", port %"U16_F")\n", pcb->local_port)); + return ERR_OK; +} + +/** + * @ingroup udp_raw + * Bind an UDP PCB to a specific netif. + * After calling this function, all packets received via this PCB + * are guaranteed to have come in via the specified netif, and all + * outgoing packets will go out via the specified netif. + * + * @param pcb UDP PCB to be bound. + * @param netif netif to bind udp pcb to. Can be NULL. + * + * @see udp_disconnect() + */ +void +udp_bind_netif(struct udp_pcb *pcb, const struct netif *netif) +{ + LWIP_ASSERT_CORE_LOCKED(); + + if (netif != NULL) { + pcb->netif_idx = netif_get_index(netif); + } else { + pcb->netif_idx = NETIF_NO_INDEX; + } +} + +/** + * @ingroup udp_raw + * Sets the remote end of the pcb. This function does not generate any + * network traffic, but only sets the remote address of the pcb. + * + * @param pcb UDP PCB to be connected with remote address ipaddr and port. + * @param ipaddr remote IP address to connect with. + * @param port remote UDP port to connect with. + * + * @return lwIP error code + * + * ipaddr & port are expected to be in the same byte order as in the pcb. + * + * The udp pcb is bound to a random local port if not already bound. + * + * @see udp_disconnect() + */ +err_t +udp_connect(struct udp_pcb *pcb, const ip_addr_t *ipaddr, u16_t port) +{ + struct udp_pcb *ipcb; + + LWIP_ASSERT_CORE_LOCKED(); + + LWIP_ERROR("udp_connect: invalid pcb", pcb != NULL, return ERR_ARG); + LWIP_ERROR("udp_connect: invalid ipaddr", ipaddr != NULL, return ERR_ARG); + + if (pcb->local_port == 0) { + err_t err = udp_bind(pcb, &pcb->local_ip, pcb->local_port); + if (err != ERR_OK) { + return err; + } + } + + ip_addr_set_ipaddr(&pcb->remote_ip, ipaddr); +#if LWIP_IPV6 && LWIP_IPV6_SCOPES + /* If the given IP address should have a zone but doesn't, assign one now, + * using the bound address to make a more informed decision when possible. */ + if (IP_IS_V6(&pcb->remote_ip) && + ip6_addr_lacks_zone(ip_2_ip6(&pcb->remote_ip), IP6_UNKNOWN)) { + ip6_addr_select_zone(ip_2_ip6(&pcb->remote_ip), ip_2_ip6(&pcb->local_ip)); + } +#endif /* LWIP_IPV6 && LWIP_IPV6_SCOPES */ + + pcb->remote_port = port; + pcb->flags |= UDP_FLAGS_CONNECTED; + + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("udp_connect: connected to ")); + ip_addr_debug_print_val(UDP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, + pcb->remote_ip); + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, (", port %"U16_F")\n", pcb->remote_port)); + + /* Insert UDP PCB into the list of active UDP PCBs. */ + for (ipcb = udp_pcbs; ipcb != NULL; ipcb = ipcb->next) { + if (pcb == ipcb) { + /* already on the list, just return */ + return ERR_OK; + } + } + /* PCB not yet on the list, add PCB now */ + pcb->next = udp_pcbs; + udp_pcbs = pcb; + return ERR_OK; +} + +/** + * @ingroup udp_raw + * Remove the remote end of the pcb. This function does not generate + * any network traffic, but only removes the remote address of the pcb. + * + * @param pcb the udp pcb to disconnect. + */ +void +udp_disconnect(struct udp_pcb *pcb) +{ + LWIP_ASSERT_CORE_LOCKED(); + + LWIP_ERROR("udp_disconnect: invalid pcb", pcb != NULL, return); + + /* reset remote address association */ +#if LWIP_IPV4 && LWIP_IPV6 + if (IP_IS_ANY_TYPE_VAL(pcb->local_ip)) { + ip_addr_copy(pcb->remote_ip, *IP_ANY_TYPE); + } else { +#endif + ip_addr_set_any(IP_IS_V6_VAL(pcb->remote_ip), &pcb->remote_ip); +#if LWIP_IPV4 && LWIP_IPV6 + } +#endif + pcb->remote_port = 0; + pcb->netif_idx = NETIF_NO_INDEX; + /* mark PCB as unconnected */ + udp_clear_flags(pcb, UDP_FLAGS_CONNECTED); +} + +/** + * @ingroup udp_raw + * Set a receive callback for a UDP PCB. + * This callback will be called when receiving a datagram for the pcb. + * + * @param pcb the pcb for which to set the recv callback + * @param recv function pointer of the callback function + * @param recv_arg additional argument to pass to the callback function + */ +void +udp_recv(struct udp_pcb *pcb, udp_recv_fn recv, void *recv_arg) +{ + LWIP_ASSERT_CORE_LOCKED(); + + LWIP_ERROR("udp_recv: invalid pcb", pcb != NULL, return); + + /* remember recv() callback and user data */ + pcb->recv = recv; + pcb->recv_arg = recv_arg; +} + +/** + * @ingroup udp_raw + * Removes and deallocates the pcb. + * + * @param pcb UDP PCB to be removed. The PCB is removed from the list of + * UDP PCB's and the data structure is freed from memory. + * + * @see udp_new() + */ +void +udp_remove(struct udp_pcb *pcb) +{ + struct udp_pcb *pcb2; + + LWIP_ASSERT_CORE_LOCKED(); + + LWIP_ERROR("udp_remove: invalid pcb", pcb != NULL, return); + + mib2_udp_unbind(pcb); + /* pcb to be removed is first in list? */ + if (udp_pcbs == pcb) { + /* make list start at 2nd pcb */ + udp_pcbs = udp_pcbs->next; + /* pcb not 1st in list */ + } else { + for (pcb2 = udp_pcbs; pcb2 != NULL; pcb2 = pcb2->next) { + /* find pcb in udp_pcbs list */ + if (pcb2->next != NULL && pcb2->next == pcb) { + /* remove pcb from list */ + pcb2->next = pcb->next; + break; + } + } + } + memp_free(MEMP_UDP_PCB, pcb); +} + +/** + * @ingroup udp_raw + * Creates a new UDP pcb which can be used for UDP communication. The + * pcb is not active until it has either been bound to a local address + * or connected to a remote address. + * + * @return The UDP PCB which was created. NULL if the PCB data structure + * could not be allocated. + * + * @see udp_remove() + */ +struct udp_pcb * +udp_new(void) +{ + struct udp_pcb *pcb; + + LWIP_ASSERT_CORE_LOCKED(); + + pcb = (struct udp_pcb *)memp_malloc(MEMP_UDP_PCB); + /* could allocate UDP PCB? */ + if (pcb != NULL) { + /* UDP Lite: by initializing to all zeroes, chksum_len is set to 0 + * which means checksum is generated over the whole datagram per default + * (recommended as default by RFC 3828). */ + /* initialize PCB to all zeroes */ + memset(pcb, 0, sizeof(struct udp_pcb)); + pcb->ttl = UDP_TTL; +#if LWIP_MULTICAST_TX_OPTIONS + udp_set_multicast_ttl(pcb, UDP_TTL); +#endif /* LWIP_MULTICAST_TX_OPTIONS */ + } + return pcb; +} + +/** + * @ingroup udp_raw + * Create a UDP PCB for specific IP type. + * The pcb is not active until it has either been bound to a local address + * or connected to a remote address. + * + * @param type IP address type, see @ref lwip_ip_addr_type definitions. + * If you want to listen to IPv4 and IPv6 (dual-stack) packets, + * supply @ref IPADDR_TYPE_ANY as argument and bind to @ref IP_ANY_TYPE. + * @return The UDP PCB which was created. NULL if the PCB data structure + * could not be allocated. + * + * @see udp_remove() + */ +struct udp_pcb * +udp_new_ip_type(u8_t type) +{ + struct udp_pcb *pcb; + + LWIP_ASSERT_CORE_LOCKED(); + + pcb = udp_new(); +#if LWIP_IPV4 && LWIP_IPV6 + if (pcb != NULL) { + IP_SET_TYPE_VAL(pcb->local_ip, type); + IP_SET_TYPE_VAL(pcb->remote_ip, type); + } +#else + LWIP_UNUSED_ARG(type); +#endif /* LWIP_IPV4 && LWIP_IPV6 */ + return pcb; +} + +/** This function is called from netif.c when address is changed + * + * @param old_addr IP address of the netif before change + * @param new_addr IP address of the netif after change + */ +void udp_netif_ip_addr_changed(const ip_addr_t *old_addr, const ip_addr_t *new_addr) +{ + struct udp_pcb *upcb; + + if (!ip_addr_isany(old_addr) && !ip_addr_isany(new_addr)) { + for (upcb = udp_pcbs; upcb != NULL; upcb = upcb->next) { + /* PCB bound to current local interface address? */ + if (ip_addr_cmp(&upcb->local_ip, old_addr)) { + /* The PCB is bound to the old ipaddr and + * is set to bound to the new one instead */ + ip_addr_copy(upcb->local_ip, *new_addr); + } + } + } +} + +#if UDP_DEBUG +/** + * Print UDP header information for debug purposes. + * + * @param udphdr pointer to the udp header in memory. + */ +void +udp_debug_print(struct udp_hdr *udphdr) +{ + LWIP_DEBUGF(UDP_DEBUG, ("UDP header:\n")); + LWIP_DEBUGF(UDP_DEBUG, ("+-------------------------------+\n")); + LWIP_DEBUGF(UDP_DEBUG, ("| %5"U16_F" | %5"U16_F" | (src port, dest port)\n", + lwip_ntohs(udphdr->src), lwip_ntohs(udphdr->dest))); + LWIP_DEBUGF(UDP_DEBUG, ("+-------------------------------+\n")); + LWIP_DEBUGF(UDP_DEBUG, ("| %5"U16_F" | 0x%04"X16_F" | (len, chksum)\n", + lwip_ntohs(udphdr->len), lwip_ntohs(udphdr->chksum))); + LWIP_DEBUGF(UDP_DEBUG, ("+-------------------------------+\n")); +} +#endif /* UDP_DEBUG */ + +#endif /* LWIP_UDP */ |