diff options
Diffstat (limited to 'tmk_core/tool/mbed/mbed-sdk/libraries/net/lwip/lwip/core/udp.c')
| -rw-r--r-- | tmk_core/tool/mbed/mbed-sdk/libraries/net/lwip/lwip/core/udp.c | 966 |
1 files changed, 966 insertions, 0 deletions
diff --git a/tmk_core/tool/mbed/mbed-sdk/libraries/net/lwip/lwip/core/udp.c b/tmk_core/tool/mbed/mbed-sdk/libraries/net/lwip/lwip/core/udp.c new file mode 100644 index 0000000000..4596ba2b79 --- /dev/null +++ b/tmk_core/tool/mbed/mbed-sdk/libraries/net/lwip/lwip/core/udp.c @@ -0,0 +1,966 @@ +/** + * @file + * User Datagram Protocol module + * + */ + +/* + * 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> + * + */ + + +/* udp.c + * + * The code for the User Datagram Protocol UDP & UDPLite (RFC 3828). + * + */ + +/* @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/netif.h" +#include "lwip/icmp.h" +#include "lwip/stats.h" +#include "lwip/snmp.h" +#include "arch/perf.h" +#include "lwip/dhcp.h" + +#include <string.h> + +/* The list of UDP PCBs */ +/* exported in udp.h (was static) */ +struct udp_pcb *udp_pcbs; + +/** + * 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. + * @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; + struct ip_hdr *iphdr; + u16_t src, dest; + u8_t local_match; + u8_t broadcast; + + PERF_START; + + UDP_STATS_INC(udp.recv); + + iphdr = (struct ip_hdr *)p->payload; + + /* Check minimum length (IP header + UDP header) + * and move payload pointer to UDP header */ + if (p->tot_len < (IPH_HL(iphdr) * 4 + UDP_HLEN) || pbuf_header(p, -(s16_t)(IPH_HL(iphdr) * 4))) { + /* 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); + snmp_inc_udpinerrors(); + pbuf_free(p); + goto end; + } + + udphdr = (struct udp_hdr *)p->payload; + + /* is broadcast packet ? */ + broadcast = ip_addr_isbroadcast(¤t_iphdr_dest, inp); + + 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 = ntohs(udphdr->src); + dest = ntohs(udphdr->dest); + + udp_debug_print(udphdr); + + /* print the UDP source and destination */ + LWIP_DEBUGF(UDP_DEBUG, + ("udp (%"U16_F".%"U16_F".%"U16_F".%"U16_F", %"U16_F") <-- " + "(%"U16_F".%"U16_F".%"U16_F".%"U16_F", %"U16_F")\n", + ip4_addr1_16(&iphdr->dest), ip4_addr2_16(&iphdr->dest), + ip4_addr3_16(&iphdr->dest), ip4_addr4_16(&iphdr->dest), ntohs(udphdr->dest), + ip4_addr1_16(&iphdr->src), ip4_addr2_16(&iphdr->src), + ip4_addr3_16(&iphdr->src), ip4_addr4_16(&iphdr->src), ntohs(udphdr->src))); + +#if LWIP_DHCP + pcb = NULL; + /* when LWIP_DHCP is active, packets to DHCP_CLIENT_PORT may only be processed by + the dhcp module, no other UDP pcb may use the local UDP port DHCP_CLIENT_PORT */ + if (dest == DHCP_CLIENT_PORT) { + /* all packets for DHCP_CLIENT_PORT not coming from DHCP_SERVER_PORT are dropped! */ + if (src == DHCP_SERVER_PORT) { + if ((inp->dhcp != NULL) && (inp->dhcp->pcb != NULL)) { + /* accept the packe if + (- broadcast or directed to us) -> DHCP is link-layer-addressed, local ip is always ANY! + - inp->dhcp->pcb->remote == ANY or iphdr->src */ + if ((ip_addr_isany(&inp->dhcp->pcb->remote_ip) || + ip_addr_cmp(&(inp->dhcp->pcb->remote_ip), ¤t_iphdr_src))) { + pcb = inp->dhcp->pcb; + } + } + } + } else +#endif /* LWIP_DHCP */ + { + prev = NULL; + local_match = 0; + 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) { + local_match = 0; + /* print the PCB local and remote address */ + LWIP_DEBUGF(UDP_DEBUG, + ("pcb (%"U16_F".%"U16_F".%"U16_F".%"U16_F", %"U16_F") --- " + "(%"U16_F".%"U16_F".%"U16_F".%"U16_F", %"U16_F")\n", + ip4_addr1_16(&pcb->local_ip), ip4_addr2_16(&pcb->local_ip), + ip4_addr3_16(&pcb->local_ip), ip4_addr4_16(&pcb->local_ip), pcb->local_port, + ip4_addr1_16(&pcb->remote_ip), ip4_addr2_16(&pcb->remote_ip), + ip4_addr3_16(&pcb->remote_ip), ip4_addr4_16(&pcb->remote_ip), pcb->remote_port)); + + /* compare PCB local addr+port to UDP destination addr+port */ + if ((pcb->local_port == dest) && + ((!broadcast && ip_addr_isany(&pcb->local_ip)) || + ip_addr_cmp(&(pcb->local_ip), ¤t_iphdr_dest) || +#if LWIP_IGMP + ip_addr_ismulticast(¤t_iphdr_dest) || +#endif /* LWIP_IGMP */ +#if IP_SOF_BROADCAST_RECV + (broadcast && (pcb->so_options & SOF_BROADCAST)))) { +#else /* IP_SOF_BROADCAST_RECV */ + (broadcast))) { +#endif /* IP_SOF_BROADCAST_RECV */ + local_match = 1; + if ((uncon_pcb == NULL) && + ((pcb->flags & UDP_FLAGS_CONNECTED) == 0)) { + /* the first unconnected matching PCB */ + uncon_pcb = pcb; + } + } + /* compare PCB remote addr+port to UDP source addr+port */ + if ((local_match != 0) && + (pcb->remote_port == src) && + (ip_addr_isany(&pcb->remote_ip) || + ip_addr_cmp(&(pcb->remote_ip), ¤t_iphdr_src))) { + /* 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 || ip_addr_cmp(&inp->ip_addr, ¤t_iphdr_dest)) { + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, ("udp_input: calculating checksum\n")); +#if LWIP_UDPLITE + if (IPH_PROTO(iphdr) == IP_PROTO_UDPLITE) { + /* Do the UDP Lite checksum */ +#if CHECKSUM_CHECK_UDP + u16_t chklen = 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) */ + UDP_STATS_INC(udp.chkerr); + UDP_STATS_INC(udp.drop); + snmp_inc_udpinerrors(); + pbuf_free(p); + goto end; + } + } + if (inet_chksum_pseudo_partial(p, ¤t_iphdr_src, ¤t_iphdr_dest, + IP_PROTO_UDPLITE, p->tot_len, chklen) != 0) { + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, + ("udp_input: UDP Lite datagram discarded due to failing checksum\n")); + UDP_STATS_INC(udp.chkerr); + UDP_STATS_INC(udp.drop); + snmp_inc_udpinerrors(); + pbuf_free(p); + goto end; + } +#endif /* CHECKSUM_CHECK_UDP */ + } else +#endif /* LWIP_UDPLITE */ + { +#if CHECKSUM_CHECK_UDP + if (udphdr->chksum != 0) { + if (inet_chksum_pseudo(p, ip_current_src_addr(), ip_current_dest_addr(), + IP_PROTO_UDP, p->tot_len) != 0) { + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, + ("udp_input: UDP datagram discarded due to failing checksum\n")); + UDP_STATS_INC(udp.chkerr); + UDP_STATS_INC(udp.drop); + snmp_inc_udpinerrors(); + pbuf_free(p); + goto end; + } + } +#endif /* CHECKSUM_CHECK_UDP */ + } + if(pbuf_header(p, -UDP_HLEN)) { + /* Can we cope with this failing? Just assert for now */ + LWIP_ASSERT("pbuf_header failed\n", 0); + UDP_STATS_INC(udp.drop); + snmp_inc_udpinerrors(); + pbuf_free(p); + goto end; + } + if (pcb != NULL) { + snmp_inc_udpindatagrams(); +#if SO_REUSE && SO_REUSE_RXTOALL + if ((broadcast || ip_addr_ismulticast(¤t_iphdr_dest)) && + ((pcb->so_options & SOF_REUSEADDR) != 0)) { + /* pass broadcast- or multicast packets to all multicast pcbs + if SOF_REUSEADDR is set on the first match */ + struct udp_pcb *mpcb; + u8_t p_header_changed = 0; + 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) && + ((!broadcast && ip_addr_isany(&mpcb->local_ip)) || + ip_addr_cmp(&(mpcb->local_ip), ¤t_iphdr_dest) || +#if LWIP_IGMP + ip_addr_ismulticast(¤t_iphdr_dest) || +#endif /* LWIP_IGMP */ +#if IP_SOF_BROADCAST_RECV + (broadcast && (mpcb->so_options & SOF_BROADCAST)))) { +#else /* IP_SOF_BROADCAST_RECV */ + (broadcast))) { +#endif /* IP_SOF_BROADCAST_RECV */ + /* pass a copy of the packet to all local matches */ + if (mpcb->recv != NULL) { + struct pbuf *q; + /* for that, move payload to IP header again */ + if (p_header_changed == 0) { + pbuf_header(p, (s16_t)((IPH_HL(iphdr) * 4) + UDP_HLEN)); + p_header_changed = 1; + } + q = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM); + if (q != NULL) { + err_t err = pbuf_copy(q, p); + if (err == ERR_OK) { + /* move payload to UDP data */ + pbuf_header(q, -(s16_t)((IPH_HL(iphdr) * 4) + UDP_HLEN)); + mpcb->recv(mpcb->recv_arg, mpcb, q, ip_current_src_addr(), src); + } + } + } + } + } + } + if (p_header_changed) { + /* and move payload to UDP data again */ + pbuf_header(p, -(s16_t)((IPH_HL(iphdr) * 4) + UDP_HLEN)); + } + } +#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 + /* No match was found, send ICMP destination port unreachable unless + destination address was broadcast/multicast. */ + if (!broadcast && + !ip_addr_ismulticast(¤t_iphdr_dest)) { + /* move payload pointer back to ip header */ + pbuf_header(p, (IPH_HL(iphdr) * 4) + UDP_HLEN); + LWIP_ASSERT("p->payload == iphdr", (p->payload == iphdr)); + icmp_dest_unreach(p, ICMP_DUR_PORT); + } +#endif /* LWIP_ICMP */ + UDP_STATS_INC(udp.proterr); + UDP_STATS_INC(udp.drop); + snmp_inc_udpnoports(); + pbuf_free(p); + } + } else { + pbuf_free(p); + } +end: + PERF_STOP("udp_input"); +} + +/** + * Send data using UDP. + * + * @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 occured. + * - ERR_MEM. Out of memory. + * - ERR_RTE. Could not find route to destination address. + * - 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) +{ + /* 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 +/** 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) +{ + /* 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 */ + +/** + * 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, + ip_addr_t *dst_ip, u16_t dst_port) +{ +#if LWIP_CHECKSUM_ON_COPY + return udp_sendto_chksum(pcb, p, dst_ip, dst_port, 0, 0); +} + +/** Same as udp_sendto(), but with checksum */ +err_t +udp_sendto_chksum(struct udp_pcb *pcb, struct pbuf *p, ip_addr_t *dst_ip, + u16_t dst_port, u8_t have_chksum, u16_t chksum) +{ +#endif /* LWIP_CHECKSUM_ON_COPY */ + struct netif *netif; + + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, ("udp_send\n")); + + /* find the outgoing network interface for this packet */ +#if LWIP_IGMP + netif = ip_route((ip_addr_ismulticast(dst_ip))?(&(pcb->multicast_ip)):(dst_ip)); +#else + netif = ip_route(dst_ip); +#endif /* LWIP_IGMP */ + + /* no outgoing network interface could be found? */ + if (netif == NULL) { + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("udp_send: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", + ip4_addr1_16(dst_ip), ip4_addr2_16(dst_ip), ip4_addr3_16(dst_ip), ip4_addr4_16(dst_ip))); + UDP_STATS_INC(udp.rterr); + return ERR_RTE; + } +#if LWIP_CHECKSUM_ON_COPY + return udp_sendto_if_chksum(pcb, p, dst_ip, dst_port, netif, have_chksum, chksum); +#else /* LWIP_CHECKSUM_ON_COPY */ + return udp_sendto_if(pcb, p, dst_ip, dst_port, netif); +#endif /* LWIP_CHECKSUM_ON_COPY */ +} + +/** + * 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, + ip_addr_t *dst_ip, u16_t dst_port, struct netif *netif) +{ +#if LWIP_CHECKSUM_ON_COPY + 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, ip_addr_t *dst_ip, + u16_t dst_port, struct netif *netif, u8_t have_chksum, + u16_t chksum) +{ +#endif /* LWIP_CHECKSUM_ON_COPY */ + struct udp_hdr *udphdr; + ip_addr_t *src_ip; + err_t err; + struct pbuf *q; /* q will be sent down the stack */ + +#if IP_SOF_BROADCAST + /* broadcast filter? */ + if ( ((pcb->so_options & SOF_BROADCAST) == 0) && 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 /* 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; + } + } + + /* not enough space to add an UDP header to first pbuf in given p chain? */ + if (pbuf_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 = htons(pcb->local_port); + udphdr->dest = htons(dst_port); + /* in UDP, 0 checksum means 'no checksum' */ + udphdr->chksum = 0x0000; + + /* Multicast Loop? */ +#if LWIP_IGMP + if (ip_addr_ismulticast(dst_ip) && ((pcb->flags & UDP_FLAGS_MULTICAST_LOOP) != 0)) { + q->flags |= PBUF_FLAG_MCASTLOOP; + } +#endif /* LWIP_IGMP */ + + + /* PCB local address is IP_ANY_ADDR? */ + if (ip_addr_isany(&pcb->local_ip)) { + /* use outgoing network interface IP address as source address */ + src_ip = &(netif->ip_addr); + } else { + /* check if UDP PCB local IP address is correct + * this could be an old address if netif->ip_addr has changed */ + if (!ip_addr_cmp(&(pcb->local_ip), &(netif->ip_addr))) { + /* local_ip doesn't match, drop the packet */ + if (q != p) { + /* free the header pbuf */ + pbuf_free(q); + q = NULL; + /* p is still referenced by the caller, and will live on */ + } + return ERR_VAL; + } + /* use UDP PCB local IP address as source address */ + src_ip = &(pcb->local_ip); + } + + 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 = htons(chklen_hdr); + /* calculate checksum */ +#if CHECKSUM_GEN_UDP + udphdr->chksum = inet_chksum_pseudo_partial(q, src_ip, dst_ip, + IP_PROTO_UDPLITE, q->tot_len, +#if !LWIP_CHECKSUM_ON_COPY + chklen); +#else /* !LWIP_CHECKSUM_ON_COPY */ + (have_chksum ? UDP_HLEN : chklen)); + 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 */ + /* output to IP */ + LWIP_DEBUGF(UDP_DEBUG, ("udp_send: ip_output_if (,,,,IP_PROTO_UDPLITE,)\n")); +#if LWIP_NETIF_HWADDRHINT + netif->addr_hint = &(pcb->addr_hint); +#endif /* LWIP_NETIF_HWADDRHINT*/ + err = ip_output_if(q, src_ip, dst_ip, pcb->ttl, pcb->tos, IP_PROTO_UDPLITE, netif); +#if LWIP_NETIF_HWADDRHINT + netif->addr_hint = NULL; +#endif /* LWIP_NETIF_HWADDRHINT*/ + } else +#endif /* LWIP_UDPLITE */ + { /* UDP */ + LWIP_DEBUGF(UDP_DEBUG, ("udp_send: UDP packet length %"U16_F"\n", q->tot_len)); + udphdr->len = htons(q->tot_len); + /* calculate checksum */ +#if CHECKSUM_GEN_UDP + if ((pcb->flags & UDP_FLAGS_NOCHKSUM) == 0) { + u16_t udpchksum; +#if LWIP_CHECKSUM_ON_COPY + if (have_chksum) { + u32_t acc; + udpchksum = inet_chksum_pseudo_partial(q, src_ip, dst_ip, IP_PROTO_UDP, + q->tot_len, UDP_HLEN); + acc = udpchksum + (u16_t)~(chksum); + udpchksum = FOLD_U32T(acc); + } else +#endif /* LWIP_CHECKSUM_ON_COPY */ + { + udpchksum = inet_chksum_pseudo(q, src_ip, dst_ip, IP_PROTO_UDP, q->tot_len); + } + + /* chksum zero must become 0xffff, as zero means 'no checksum' */ + if (udpchksum == 0x0000) { + udpchksum = 0xffff; + } + udphdr->chksum = udpchksum; + } +#endif /* CHECKSUM_GEN_UDP */ + LWIP_DEBUGF(UDP_DEBUG, ("udp_send: UDP checksum 0x%04"X16_F"\n", udphdr->chksum)); + LWIP_DEBUGF(UDP_DEBUG, ("udp_send: ip_output_if (,,,,IP_PROTO_UDP,)\n")); + /* output to IP */ +#if LWIP_NETIF_HWADDRHINT + netif->addr_hint = &(pcb->addr_hint); +#endif /* LWIP_NETIF_HWADDRHINT*/ + err = ip_output_if(q, src_ip, dst_ip, pcb->ttl, pcb->tos, IP_PROTO_UDP, netif); +#if LWIP_NETIF_HWADDRHINT + netif->addr_hint = NULL; +#endif /* LWIP_NETIF_HWADDRHINT*/ + } + /* TODO: must this be increased even if error occured? */ + snmp_inc_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; +} + +/** + * 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_ADDR_ANY 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 occured. + * - 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, ip_addr_t *ipaddr, u16_t port) +{ + struct udp_pcb *ipcb; + u8_t rebind; + + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, ("udp_bind(ipaddr = ")); + ip_addr_debug_print(UDP_DEBUG, 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) { + /* pcb may occur at most once in active list */ + LWIP_ASSERT("rebind == 0", rebind == 0); + /* pcb already in list, just rebind */ + rebind = 1; + } + + /* By default, we don't allow to bind to a port that any other udp + PCB is alread bound to, unless *all* PCBs with that port have tha + REUSEADDR flag set. */ +#if SO_REUSE + else if (((pcb->so_options & SOF_REUSEADDR) == 0) && + ((ipcb->so_options & SOF_REUSEADDR) == 0)) { +#else /* SO_REUSE */ + /* port matches that of PCB in list and REUSEADDR not set -> reject */ + else { +#endif /* SO_REUSE */ + if ((ipcb->local_port == port) && + /* IP address matches, or one is IP_ADDR_ANY? */ + (ip_addr_isany(&(ipcb->local_ip)) || + ip_addr_isany(ipaddr) || + ip_addr_cmp(&(ipcb->local_ip), ipaddr))) { + /* 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(&pcb->local_ip, ipaddr); + + /* no port specified? */ + if (port == 0) { +#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 +#endif + port = UDP_LOCAL_PORT_RANGE_START; + ipcb = udp_pcbs; + while ((ipcb != NULL) && (port != UDP_LOCAL_PORT_RANGE_END)) { + if (ipcb->local_port == port) { + /* port is already used by another udp_pcb */ + port++; + /* restart scanning all udp pcbs */ + ipcb = udp_pcbs; + } else { + /* go on with next udp pcb */ + ipcb = ipcb->next; + } + } + if (ipcb != NULL) { + /* no more ports available in local range */ + LWIP_DEBUGF(UDP_DEBUG, ("udp_bind: out of free UDP ports\n")); + return ERR_USE; + } + } + pcb->local_port = port; + snmp_insert_udpidx_tree(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 %"U16_F".%"U16_F".%"U16_F".%"U16_F", port %"U16_F"\n", + ip4_addr1_16(&pcb->local_ip), ip4_addr2_16(&pcb->local_ip), + ip4_addr3_16(&pcb->local_ip), ip4_addr4_16(&pcb->local_ip), + pcb->local_port)); + return ERR_OK; +} +/** + * Connect an UDP PCB. + * + * This will associate the UDP PCB with the remote address. + * + * @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, ip_addr_t *ipaddr, u16_t port) +{ + struct udp_pcb *ipcb; + + 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(&pcb->remote_ip, ipaddr); + pcb->remote_port = port; + pcb->flags |= UDP_FLAGS_CONNECTED; +/** TODO: this functionality belongs in upper layers */ +#ifdef LWIP_UDP_TODO + /* Nail down local IP for netconn_addr()/getsockname() */ + if (ip_addr_isany(&pcb->local_ip) && !ip_addr_isany(&pcb->remote_ip)) { + struct netif *netif; + + if ((netif = ip_route(&(pcb->remote_ip))) == NULL) { + LWIP_DEBUGF(UDP_DEBUG, ("udp_connect: No route to 0x%lx\n", pcb->remote_ip.addr)); + UDP_STATS_INC(udp.rterr); + return ERR_RTE; + } + /** TODO: this will bind the udp pcb locally, to the interface which + is used to route output packets to the remote address. However, we + might want to accept incoming packets on any interface! */ + pcb->local_ip = netif->ip_addr; + } else if (ip_addr_isany(&pcb->remote_ip)) { + pcb->local_ip.addr = 0; + } +#endif + LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, + ("udp_connect: connected to %"U16_F".%"U16_F".%"U16_F".%"U16_F",port %"U16_F"\n", + ip4_addr1_16(&pcb->local_ip), ip4_addr2_16(&pcb->local_ip), + ip4_addr3_16(&pcb->local_ip), ip4_addr4_16(&pcb->local_ip), + pcb->local_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; +} + +/** + * Disconnect a UDP PCB + * + * @param pcb the udp pcb to disconnect. + */ +void +udp_disconnect(struct udp_pcb *pcb) +{ + /* reset remote address association */ + ip_addr_set_any(&pcb->remote_ip); + pcb->remote_port = 0; + /* mark PCB as unconnected */ + pcb->flags &= ~UDP_FLAGS_CONNECTED; +} + +/** + * 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 wich 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) +{ + /* remember recv() callback and user data */ + pcb->recv = recv; + pcb->recv_arg = recv_arg; +} + +/** + * Remove an UDP 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; + + snmp_delete_udpidx_tree(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; + } + } + } + memp_free(MEMP_UDP_PCB, pcb); +} + +/** + * Create a UDP PCB. + * + * @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; + 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; + } + return pcb; +} + +#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", + ntohs(udphdr->src), ntohs(udphdr->dest))); + LWIP_DEBUGF(UDP_DEBUG, ("+-------------------------------+\n")); + LWIP_DEBUGF(UDP_DEBUG, ("| %5"U16_F" | 0x%04"X16_F" | (len, chksum)\n", + ntohs(udphdr->len), ntohs(udphdr->chksum))); + LWIP_DEBUGF(UDP_DEBUG, ("+-------------------------------+\n")); +} +#endif /* UDP_DEBUG */ + +#endif /* LWIP_UDP */ |