Stripped down version of Segundos NetService library (http://mbed.org/users/segundo/libraries/NetServices ). I have removed all NetServices, and all functions which had been disabled. Use this version when you need only pure TCP or UDP functions - this library compiles faster.
Dependents: christmasLights device_server pop3demo device_server_udp ... more
Diff: lwip/core/ipv4/ip.c
- Revision:
- 1:9d93f4dc2f46
- Parent:
- 0:8b387bed54c2
--- a/lwip/core/ipv4/ip.c Mon Jan 10 21:03:11 2011 +0000 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,857 +0,0 @@ -/** - * @file - * This is the IPv4 layer implementation for incoming and outgoing IP traffic. - * - * @see ip_frag.c - * - */ - -/* - * 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> - * - */ - -#include "lwip/opt.h" -#include "lwip/ip.h" -#include "lwip/def.h" -#include "lwip/mem.h" -#include "lwip/ip_frag.h" -#include "lwip/inet_chksum.h" -#include "lwip/netif.h" -#include "lwip/icmp.h" -#include "lwip/igmp.h" -#include "lwip/raw.h" -#include "lwip/udp.h" -#include "lwip/tcp_impl.h" -#include "lwip/snmp.h" -#include "lwip/dhcp.h" -#include "lwip/autoip.h" -#include "lwip/stats.h" -#include "arch/perf.h" - -#include <string.h> - -/** Set this to 0 in the rare case of wanting to call an extra function to - * generate the IP checksum (in contrast to calculating it on-the-fly). */ -#ifndef LWIP_INLINE_IP_CHKSUM -#define LWIP_INLINE_IP_CHKSUM 1 -#endif -#if LWIP_INLINE_IP_CHKSUM && CHECKSUM_GEN_IP -#define CHECKSUM_GEN_IP_INLINE 1 -#else -#define CHECKSUM_GEN_IP_INLINE 0 -#endif - -#if LWIP_DHCP || defined(LWIP_IP_ACCEPT_UDP_PORT) -#define IP_ACCEPT_LINK_LAYER_ADDRESSING 1 - -/** Some defines for DHCP to let link-layer-addressed packets through while the - * netif is down. - * To use this in your own application/protocol, define LWIP_IP_ACCEPT_UDP_PORT - * to return 1 if the port is accepted and 0 if the port is not accepted. - */ -#if LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) -/* accept DHCP client port and custom port */ -#define IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(port) (((port) == PP_NTOHS(DHCP_CLIENT_PORT)) \ - || (LWIP_IP_ACCEPT_UDP_PORT(port))) -#elif defined(LWIP_IP_ACCEPT_UDP_PORT) /* LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) */ -/* accept custom port only */ -#define IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(port) (LWIP_IP_ACCEPT_UDP_PORT(dst_port)) -#else /* LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) */ -/* accept DHCP client port only */ -#define IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(port) ((port) == PP_NTOHS(DHCP_CLIENT_PORT)) -#endif /* LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) */ - -#else /* LWIP_DHCP */ -#define IP_ACCEPT_LINK_LAYER_ADDRESSING 0 -#endif /* LWIP_DHCP */ - -/** - * The interface that provided the packet for the current callback - * invocation. - */ -struct netif *current_netif; - -/** - * Header of the input packet currently being processed. - */ -const struct ip_hdr *current_header; -/** Source IP address of current_header */ -ip_addr_t current_iphdr_src; -/** Destination IP address of current_header */ -ip_addr_t current_iphdr_dest; - -/** The IP header ID of the next outgoing IP packet */ -static u16_t ip_id; - -/** - * Finds the appropriate network interface for a given IP address. It - * searches the list of network interfaces linearly. A match is found - * if the masked IP address of the network interface equals the masked - * IP address given to the function. - * - * @param dest the destination IP address for which to find the route - * @return the netif on which to send to reach dest - */ -struct netif * -ip_route(ip_addr_t *dest) -{ - struct netif *netif; - - /* iterate through netifs */ - for(netif = netif_list; netif != NULL; netif = netif->next) { - /* network mask matches? */ - if (netif_is_up(netif)) { - if (ip_addr_netcmp(dest, &(netif->ip_addr), &(netif->netmask))) { - /* return netif on which to forward IP packet */ - return netif; - } - } - } - if ((netif_default == NULL) || (!netif_is_up(netif_default))) { - LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_route: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", - ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest))); - IP_STATS_INC(ip.rterr); - snmp_inc_ipoutnoroutes(); - return NULL; - } - /* no matching netif found, use default netif */ - return netif_default; -} - -#if IP_FORWARD -/** - * Forwards an IP packet. It finds an appropriate route for the - * packet, decrements the TTL value of the packet, adjusts the - * checksum and outputs the packet on the appropriate interface. - * - * @param p the packet to forward (p->payload points to IP header) - * @param iphdr the IP header of the input packet - * @param inp the netif on which this packet was received - */ -static void -ip_forward(struct pbuf *p, struct ip_hdr *iphdr, struct netif *inp) -{ - struct netif *netif; - - PERF_START; - - /* RFC3927 2.7: do not forward link-local addresses */ - if (ip_addr_islinklocal(¤t_iphdr_dest)) { - LWIP_DEBUGF(IP_DEBUG, ("ip_forward: not forwarding LLA %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", - ip4_addr1_16(¤t_iphdr_dest), ip4_addr2_16(¤t_iphdr_dest), - ip4_addr3_16(¤t_iphdr_dest), ip4_addr4_16(¤t_iphdr_dest))); - goto return_noroute; - } - - /* Find network interface where to forward this IP packet to. */ - netif = ip_route(¤t_iphdr_dest); - if (netif == NULL) { - LWIP_DEBUGF(IP_DEBUG, ("ip_forward: no forwarding route for %"U16_F".%"U16_F".%"U16_F".%"U16_F" found\n", - ip4_addr1_16(¤t_iphdr_dest), ip4_addr2_16(¤t_iphdr_dest), - ip4_addr3_16(¤t_iphdr_dest), ip4_addr4_16(¤t_iphdr_dest))); - goto return_noroute; - } - /* Do not forward packets onto the same network interface on which - * they arrived. */ - if (netif == inp) { - LWIP_DEBUGF(IP_DEBUG, ("ip_forward: not bouncing packets back on incoming interface.\n")); - goto return_noroute; - } - - /* decrement TTL */ - IPH_TTL_SET(iphdr, IPH_TTL(iphdr) - 1); - /* send ICMP if TTL == 0 */ - if (IPH_TTL(iphdr) == 0) { - snmp_inc_ipinhdrerrors(); -#if LWIP_ICMP - /* Don't send ICMP messages in response to ICMP messages */ - if (IPH_PROTO(iphdr) != IP_PROTO_ICMP) { - icmp_time_exceeded(p, ICMP_TE_TTL); - } -#endif /* LWIP_ICMP */ - return; - } - - /* Incrementally update the IP checksum. */ - if (IPH_CHKSUM(iphdr) >= PP_HTONS(0xffff - 0x100)) { - IPH_CHKSUM_SET(iphdr, IPH_CHKSUM(iphdr) + PP_HTONS(0x100) + 1); - } else { - IPH_CHKSUM_SET(iphdr, IPH_CHKSUM(iphdr) + PP_HTONS(0x100)); - } - - LWIP_DEBUGF(IP_DEBUG, ("ip_forward: forwarding packet to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", - ip4_addr1_16(¤t_iphdr_dest), ip4_addr2_16(¤t_iphdr_dest), - ip4_addr3_16(¤t_iphdr_dest), ip4_addr4_16(¤t_iphdr_dest))); - - IP_STATS_INC(ip.fw); - IP_STATS_INC(ip.xmit); - snmp_inc_ipforwdatagrams(); - - PERF_STOP("ip_forward"); - /* transmit pbuf on chosen interface */ - netif->output(netif, p, ¤t_iphdr_dest); - return; -return_noroute: - snmp_inc_ipoutnoroutes(); -} -#endif /* IP_FORWARD */ - -/** - * This function is called by the network interface device driver when - * an IP packet is received. The function does the basic checks of the - * IP header such as packet size being at least larger than the header - * size etc. If the packet was not destined for us, the packet is - * forwarded (using ip_forward). The IP checksum is always checked. - * - * Finally, the packet is sent to the upper layer protocol input function. - * - * @param p the received IP packet (p->payload points to IP header) - * @param inp the netif on which this packet was received - * @return ERR_OK if the packet was processed (could return ERR_* if it wasn't - * processed, but currently always returns ERR_OK) - */ -err_t -ip_input(struct pbuf *p, struct netif *inp) -{ - struct ip_hdr *iphdr; - struct netif *netif; - u16_t iphdr_hlen; - u16_t iphdr_len; -#if IP_ACCEPT_LINK_LAYER_ADDRESSING - int check_ip_src=1; -#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */ - - IP_STATS_INC(ip.recv); - snmp_inc_ipinreceives(); - - /* identify the IP header */ - iphdr = (struct ip_hdr *)p->payload; - if (IPH_V(iphdr) != 4) { - LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_WARNING, ("IP packet dropped due to bad version number %"U16_F"\n", IPH_V(iphdr))); - ip_debug_print(p); - pbuf_free(p); - IP_STATS_INC(ip.err); - IP_STATS_INC(ip.drop); - snmp_inc_ipinhdrerrors(); - return ERR_OK; - } - - /* obtain IP header length in number of 32-bit words */ - iphdr_hlen = IPH_HL(iphdr); - /* calculate IP header length in bytes */ - iphdr_hlen *= 4; - /* obtain ip length in bytes */ - iphdr_len = ntohs(IPH_LEN(iphdr)); - - /* header length exceeds first pbuf length, or ip length exceeds total pbuf length? */ - if ((iphdr_hlen > p->len) || (iphdr_len > p->tot_len)) { - if (iphdr_hlen > p->len) { - LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, - ("IP header (len %"U16_F") does not fit in first pbuf (len %"U16_F"), IP packet dropped.\n", - iphdr_hlen, p->len)); - } - if (iphdr_len > p->tot_len) { - LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, - ("IP (len %"U16_F") is longer than pbuf (len %"U16_F"), IP packet dropped.\n", - iphdr_len, p->tot_len)); - } - /* free (drop) packet pbufs */ - pbuf_free(p); - IP_STATS_INC(ip.lenerr); - IP_STATS_INC(ip.drop); - snmp_inc_ipindiscards(); - return ERR_OK; - } - - /* verify checksum */ -#if CHECKSUM_CHECK_IP - if (inet_chksum(iphdr, iphdr_hlen) != 0) { - - LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, - ("Checksum (0x%"X16_F") failed, IP packet dropped.\n", inet_chksum(iphdr, iphdr_hlen))); - ip_debug_print(p); - pbuf_free(p); - IP_STATS_INC(ip.chkerr); - IP_STATS_INC(ip.drop); - snmp_inc_ipinhdrerrors(); - return ERR_OK; - } -#endif - - /* Trim pbuf. This should have been done at the netif layer, - * but we'll do it anyway just to be sure that its done. */ - pbuf_realloc(p, iphdr_len); - - /* copy IP addresses to aligned ip_addr_t */ - ip_addr_copy(current_iphdr_dest, iphdr->dest); - ip_addr_copy(current_iphdr_src, iphdr->src); - - /* match packet against an interface, i.e. is this packet for us? */ -#if LWIP_IGMP - if (ip_addr_ismulticast(¤t_iphdr_dest)) { - if ((inp->flags & NETIF_FLAG_IGMP) && (igmp_lookfor_group(inp, ¤t_iphdr_dest))) { - netif = inp; - } else { - netif = NULL; - } - } else -#endif /* LWIP_IGMP */ - { - /* start trying with inp. if that's not acceptable, start walking the - list of configured netifs. - 'first' is used as a boolean to mark whether we started walking the list */ - int first = 1; - netif = inp; - do { - LWIP_DEBUGF(IP_DEBUG, ("ip_input: iphdr->dest 0x%"X32_F" netif->ip_addr 0x%"X32_F" (0x%"X32_F", 0x%"X32_F", 0x%"X32_F")\n", - ip4_addr_get_u32(&iphdr->dest), ip4_addr_get_u32(&netif->ip_addr), - ip4_addr_get_u32(&iphdr->dest) & ip4_addr_get_u32(&netif->netmask), - ip4_addr_get_u32(&netif->ip_addr) & ip4_addr_get_u32(&netif->netmask), - ip4_addr_get_u32(&iphdr->dest) & ~ip4_addr_get_u32(&netif->netmask))); - - /* interface is up and configured? */ - if ((netif_is_up(netif)) && (!ip_addr_isany(&(netif->ip_addr)))) { - /* unicast to this interface address? */ - if (ip_addr_cmp(¤t_iphdr_dest, &(netif->ip_addr)) || - /* or broadcast on this interface network address? */ - ip_addr_isbroadcast(¤t_iphdr_dest, netif)) { - LWIP_DEBUGF(IP_DEBUG, ("ip_input: packet accepted on interface %c%c\n", - netif->name[0], netif->name[1])); - /* break out of for loop */ - break; - } -#if LWIP_AUTOIP - /* connections to link-local addresses must persist after changing - the netif's address (RFC3927 ch. 1.9) */ - if ((netif->autoip != NULL) && - ip_addr_cmp(¤t_iphdr_dest, &(netif->autoip->llipaddr))) { - LWIP_DEBUGF(IP_DEBUG, ("ip_input: LLA packet accepted on interface %c%c\n", - netif->name[0], netif->name[1])); - /* break out of for loop */ - break; - } -#endif /* LWIP_AUTOIP */ - } - if (first) { - first = 0; - netif = netif_list; - } else { - netif = netif->next; - } - if (netif == inp) { - netif = netif->next; - } - } while(netif != NULL); - } - -#if IP_ACCEPT_LINK_LAYER_ADDRESSING - /* Pass DHCP messages regardless of destination address. DHCP traffic is addressed - * using link layer addressing (such as Ethernet MAC) so we must not filter on IP. - * According to RFC 1542 section 3.1.1, referred by RFC 2131). - * - * If you want to accept private broadcast communication while a netif is down, - * define LWIP_IP_ACCEPT_UDP_PORT(dst_port), e.g.: - * - * #define LWIP_IP_ACCEPT_UDP_PORT(dst_port) ((dst_port) == PP_NTOHS(12345)) - */ - if (netif == NULL) { - /* remote port is DHCP server? */ - if (IPH_PROTO(iphdr) == IP_PROTO_UDP) { - struct udp_hdr *udphdr = (struct udp_hdr *)((u8_t *)iphdr + iphdr_hlen); - LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: UDP packet to DHCP client port %"U16_F"\n", - ntohs(udphdr->dest))); - if (IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(udphdr->dest)) { - LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: DHCP packet accepted.\n")); - netif = inp; - check_ip_src = 0; - } - } - } -#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */ - - /* broadcast or multicast packet source address? Compliant with RFC 1122: 3.2.1.3 */ -#if IP_ACCEPT_LINK_LAYER_ADDRESSING - /* DHCP servers need 0.0.0.0 to be allowed as source address (RFC 1.1.2.2: 3.2.1.3/a) */ - if (check_ip_src && !ip_addr_isany(¤t_iphdr_src)) -#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */ - { if ((ip_addr_isbroadcast(¤t_iphdr_src, inp)) || - (ip_addr_ismulticast(¤t_iphdr_src))) { - /* packet source is not valid */ - LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING, ("ip_input: packet source is not valid.\n")); - /* free (drop) packet pbufs */ - pbuf_free(p); - IP_STATS_INC(ip.drop); - snmp_inc_ipinaddrerrors(); - snmp_inc_ipindiscards(); - return ERR_OK; - } - } - - /* packet not for us? */ - if (netif == NULL) { - /* packet not for us, route or discard */ - LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: packet not for us.\n")); -#if IP_FORWARD - /* non-broadcast packet? */ - if (!ip_addr_isbroadcast(¤t_iphdr_dest, inp)) { - /* try to forward IP packet on (other) interfaces */ - ip_forward(p, iphdr, inp); - } else -#endif /* IP_FORWARD */ - { - snmp_inc_ipinaddrerrors(); - snmp_inc_ipindiscards(); - } - pbuf_free(p); - return ERR_OK; - } - /* packet consists of multiple fragments? */ - if ((IPH_OFFSET(iphdr) & PP_HTONS(IP_OFFMASK | IP_MF)) != 0) { -#if IP_REASSEMBLY /* packet fragment reassembly code present? */ - LWIP_DEBUGF(IP_DEBUG, ("IP packet is a fragment (id=0x%04"X16_F" tot_len=%"U16_F" len=%"U16_F" MF=%"U16_F" offset=%"U16_F"), calling ip_reass()\n", - ntohs(IPH_ID(iphdr)), p->tot_len, ntohs(IPH_LEN(iphdr)), !!(IPH_OFFSET(iphdr) & PP_HTONS(IP_MF)), (ntohs(IPH_OFFSET(iphdr)) & IP_OFFMASK)*8)); - /* reassemble the packet*/ - p = ip_reass(p); - /* packet not fully reassembled yet? */ - if (p == NULL) { - return ERR_OK; - } - iphdr = (struct ip_hdr *)p->payload; -#else /* IP_REASSEMBLY == 0, no packet fragment reassembly code present */ - pbuf_free(p); - LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("IP packet dropped since it was fragmented (0x%"X16_F") (while IP_REASSEMBLY == 0).\n", - ntohs(IPH_OFFSET(iphdr)))); - IP_STATS_INC(ip.opterr); - IP_STATS_INC(ip.drop); - /* unsupported protocol feature */ - snmp_inc_ipinunknownprotos(); - return ERR_OK; -#endif /* IP_REASSEMBLY */ - } - -#if IP_OPTIONS_ALLOWED == 0 /* no support for IP options in the IP header? */ - -#if LWIP_IGMP - /* there is an extra "router alert" option in IGMP messages which we allow for but do not police */ - if((iphdr_hlen > IP_HLEN) && (IPH_PROTO(iphdr) != IP_PROTO_IGMP)) { -#else - if (iphdr_hlen > IP_HLEN) { -#endif /* LWIP_IGMP */ - LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("IP packet dropped since there were IP options (while IP_OPTIONS_ALLOWED == 0).\n")); - pbuf_free(p); - IP_STATS_INC(ip.opterr); - IP_STATS_INC(ip.drop); - /* unsupported protocol feature */ - snmp_inc_ipinunknownprotos(); - return ERR_OK; - } -#endif /* IP_OPTIONS_ALLOWED == 0 */ - - /* send to upper layers */ - LWIP_DEBUGF(IP_DEBUG, ("ip_input: \n")); - ip_debug_print(p); - LWIP_DEBUGF(IP_DEBUG, ("ip_input: p->len %"U16_F" p->tot_len %"U16_F"\n", p->len, p->tot_len)); - - current_netif = inp; - current_header = iphdr; - -#if LWIP_RAW - /* raw input did not eat the packet? */ - if (raw_input(p, inp) == 0) -#endif /* LWIP_RAW */ - { - - switch (IPH_PROTO(iphdr)) { -#if LWIP_UDP - case IP_PROTO_UDP: -#if LWIP_UDPLITE - case IP_PROTO_UDPLITE: -#endif /* LWIP_UDPLITE */ - snmp_inc_ipindelivers(); - udp_input(p, inp); - break; -#endif /* LWIP_UDP */ -#if LWIP_TCP - case IP_PROTO_TCP: - snmp_inc_ipindelivers(); - tcp_input(p, inp); - break; -#endif /* LWIP_TCP */ -#if LWIP_ICMP - case IP_PROTO_ICMP: - snmp_inc_ipindelivers(); - icmp_input(p, inp); - break; -#endif /* LWIP_ICMP */ -#if LWIP_IGMP - case IP_PROTO_IGMP: - igmp_input(p, inp, ¤t_iphdr_dest); - break; -#endif /* LWIP_IGMP */ - default: -#if LWIP_ICMP - /* send ICMP destination protocol unreachable unless is was a broadcast */ - if (!ip_addr_isbroadcast(¤t_iphdr_dest, inp) && - !ip_addr_ismulticast(¤t_iphdr_dest)) { - p->payload = iphdr; - icmp_dest_unreach(p, ICMP_DUR_PROTO); - } -#endif /* LWIP_ICMP */ - pbuf_free(p); - - LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("Unsupported transport protocol %"U16_F"\n", IPH_PROTO(iphdr))); - - IP_STATS_INC(ip.proterr); - IP_STATS_INC(ip.drop); - snmp_inc_ipinunknownprotos(); - } - } - - current_netif = NULL; - current_header = NULL; - ip_addr_set_any(¤t_iphdr_src); - ip_addr_set_any(¤t_iphdr_dest); - - return ERR_OK; -} - -/** - * Sends an IP packet on a network interface. This function constructs - * the IP header and calculates the IP header checksum. If the source - * IP address is NULL, the IP address of the outgoing network - * interface is filled in as source address. - * If the destination IP address is IP_HDRINCL, p is assumed to already - * include an IP header and p->payload points to it instead of the data. - * - * @param p the packet to send (p->payload points to the data, e.g. next - protocol header; if dest == IP_HDRINCL, p already includes an IP - header and p->payload points to that IP header) - * @param src the source IP address to send from (if src == IP_ADDR_ANY, the - * IP address of the netif used to send is used as source address) - * @param dest the destination IP address to send the packet to - * @param ttl the TTL value to be set in the IP header - * @param tos the TOS value to be set in the IP header - * @param proto the PROTOCOL to be set in the IP header - * @param netif the netif on which to send this packet - * @return ERR_OK if the packet was sent OK - * ERR_BUF if p doesn't have enough space for IP/LINK headers - * returns errors returned by netif->output - * - * @note ip_id: RFC791 "some host may be able to simply use - * unique identifiers independent of destination" - */ -err_t -ip_output_if(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest, - u8_t ttl, u8_t tos, - u8_t proto, struct netif *netif) -{ -#if IP_OPTIONS_SEND - return ip_output_if_opt(p, src, dest, ttl, tos, proto, netif, NULL, 0); -} - -/** - * Same as ip_output_if() but with the possibility to include IP options: - * - * @ param ip_options pointer to the IP options, copied into the IP header - * @ param optlen length of ip_options - */ -err_t ip_output_if_opt(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest, - u8_t ttl, u8_t tos, u8_t proto, struct netif *netif, void *ip_options, - u16_t optlen) -{ -#endif /* IP_OPTIONS_SEND */ - struct ip_hdr *iphdr; - ip_addr_t dest_addr; -#if CHECKSUM_GEN_IP_INLINE - u32_t chk_sum = 0; -#endif /* CHECKSUM_GEN_IP_INLINE */ - - /* pbufs passed to IP must have a ref-count of 1 as their payload pointer - gets altered as the packet is passed down the stack */ - LWIP_ASSERT("p->ref == 1", p->ref == 1); - - snmp_inc_ipoutrequests(); - - /* Should the IP header be generated or is it already included in p? */ - if (dest != IP_HDRINCL) { - u16_t ip_hlen = IP_HLEN; -#if IP_OPTIONS_SEND - u16_t optlen_aligned = 0; - if (optlen != 0) { -#if CHECKSUM_GEN_IP_INLINE - int i; -#endif /* CHECKSUM_GEN_IP_INLINE */ - /* round up to a multiple of 4 */ - optlen_aligned = ((optlen + 3) & ~3); - ip_hlen += optlen_aligned; - /* First write in the IP options */ - if (pbuf_header(p, optlen_aligned)) { - LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_output_if_opt: not enough room for IP options in pbuf\n")); - IP_STATS_INC(ip.err); - snmp_inc_ipoutdiscards(); - return ERR_BUF; - } - MEMCPY(p->payload, ip_options, optlen); - if (optlen < optlen_aligned) { - /* zero the remaining bytes */ - memset(((char*)p->payload) + optlen, 0, optlen_aligned - optlen); - } -#if CHECKSUM_GEN_IP_INLINE - for (i = 0; i < optlen_aligned; i += sizeof(u16_t)) { - chk_sum += ((u16_t*)p->payload)[i]; - } -#endif /* CHECKSUM_GEN_IP_INLINE */ - } -#endif /* IP_OPTIONS_SEND */ - /* generate IP header */ - if (pbuf_header(p, IP_HLEN)) { - LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_output: not enough room for IP header in pbuf\n")); - - IP_STATS_INC(ip.err); - snmp_inc_ipoutdiscards(); - return ERR_BUF; - } - - iphdr = (struct ip_hdr *)p->payload; - LWIP_ASSERT("check that first pbuf can hold struct ip_hdr", - (p->len >= sizeof(struct ip_hdr))); - - IPH_TTL_SET(iphdr, ttl); - IPH_PROTO_SET(iphdr, proto); -#if CHECKSUM_GEN_IP_INLINE - chk_sum += LWIP_MAKE_U16(proto, ttl); -#endif /* CHECKSUM_GEN_IP_INLINE */ - - /* dest cannot be NULL here */ - ip_addr_copy(iphdr->dest, *dest); -#if CHECKSUM_GEN_IP_INLINE - chk_sum += ip4_addr_get_u32(&iphdr->dest) & 0xFFFF; - chk_sum += ip4_addr_get_u32(&iphdr->dest) >> 16; -#endif /* CHECKSUM_GEN_IP_INLINE */ - - IPH_VHLTOS_SET(iphdr, 4, ip_hlen / 4, tos); -#if CHECKSUM_GEN_IP_INLINE - chk_sum += iphdr->_v_hl_tos; -#endif /* CHECKSUM_GEN_IP_INLINE */ - IPH_LEN_SET(iphdr, htons(p->tot_len)); -#if CHECKSUM_GEN_IP_INLINE - chk_sum += iphdr->_len; -#endif /* CHECKSUM_GEN_IP_INLINE */ - IPH_OFFSET_SET(iphdr, 0); - IPH_ID_SET(iphdr, htons(ip_id)); -#if CHECKSUM_GEN_IP_INLINE - chk_sum += iphdr->_id; -#endif /* CHECKSUM_GEN_IP_INLINE */ - ++ip_id; - - if (ip_addr_isany(src)) { - ip_addr_copy(iphdr->src, netif->ip_addr); - } else { - /* src cannot be NULL here */ - ip_addr_copy(iphdr->src, *src); - } - -#if CHECKSUM_GEN_IP_INLINE - chk_sum += ip4_addr_get_u32(&iphdr->src) & 0xFFFF; - chk_sum += ip4_addr_get_u32(&iphdr->src) >> 16; - chk_sum = (chk_sum >> 16) + (chk_sum & 0xFFFF); - chk_sum = (chk_sum >> 16) + chk_sum; - chk_sum = ~chk_sum; - iphdr->_chksum = chk_sum; /* network order */ -#else /* CHECKSUM_GEN_IP_INLINE */ - IPH_CHKSUM_SET(iphdr, 0); -#if CHECKSUM_GEN_IP - IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, ip_hlen)); -#endif -#endif /* CHECKSUM_GEN_IP_INLINE */ - } else { - /* IP header already included in p */ - iphdr = (struct ip_hdr *)p->payload; - ip_addr_copy(dest_addr, iphdr->dest); - dest = &dest_addr; - } - - IP_STATS_INC(ip.xmit); - - LWIP_DEBUGF(IP_DEBUG, ("ip_output_if: %c%c%"U16_F"\n", netif->name[0], netif->name[1], netif->num)); - ip_debug_print(p); - -#if ENABLE_LOOPBACK - if (ip_addr_cmp(dest, &netif->ip_addr)) { - /* Packet to self, enqueue it for loopback */ - LWIP_DEBUGF(IP_DEBUG, ("netif_loop_output()")); - return netif_loop_output(netif, p, dest); - } -#if LWIP_IGMP - if ((p->flags & PBUF_FLAG_MCASTLOOP) != 0) { - netif_loop_output(netif, p, dest); - } -#endif /* LWIP_IGMP */ -#endif /* ENABLE_LOOPBACK */ -#if IP_FRAG - /* don't fragment if interface has mtu set to 0 [loopif] */ - if (netif->mtu && (p->tot_len > netif->mtu)) { - return ip_frag(p, netif, dest); - } -#endif /* IP_FRAG */ - - LWIP_DEBUGF(IP_DEBUG, ("netif->output()")); - return netif->output(netif, p, dest); -} - -/** - * Simple interface to ip_output_if. It finds the outgoing network - * interface and calls upon ip_output_if to do the actual work. - * - * @param p the packet to send (p->payload points to the data, e.g. next - protocol header; if dest == IP_HDRINCL, p already includes an IP - header and p->payload points to that IP header) - * @param src the source IP address to send from (if src == IP_ADDR_ANY, the - * IP address of the netif used to send is used as source address) - * @param dest the destination IP address to send the packet to - * @param ttl the TTL value to be set in the IP header - * @param tos the TOS value to be set in the IP header - * @param proto the PROTOCOL to be set in the IP header - * - * @return ERR_RTE if no route is found - * see ip_output_if() for more return values - */ -err_t -ip_output(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest, - u8_t ttl, u8_t tos, u8_t proto) -{ - struct netif *netif; - - /* pbufs passed to IP must have a ref-count of 1 as their payload pointer - gets altered as the packet is passed down the stack */ - LWIP_ASSERT("p->ref == 1", p->ref == 1); - - if ((netif = ip_route(dest)) == NULL) { - LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", - ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest))); - IP_STATS_INC(ip.rterr); - return ERR_RTE; - } - - return ip_output_if(p, src, dest, ttl, tos, proto, netif); -} - -#if LWIP_NETIF_HWADDRHINT -/** Like ip_output, but takes and addr_hint pointer that is passed on to netif->addr_hint - * before calling ip_output_if. - * - * @param p the packet to send (p->payload points to the data, e.g. next - protocol header; if dest == IP_HDRINCL, p already includes an IP - header and p->payload points to that IP header) - * @param src the source IP address to send from (if src == IP_ADDR_ANY, the - * IP address of the netif used to send is used as source address) - * @param dest the destination IP address to send the packet to - * @param ttl the TTL value to be set in the IP header - * @param tos the TOS value to be set in the IP header - * @param proto the PROTOCOL to be set in the IP header - * @param addr_hint address hint pointer set to netif->addr_hint before - * calling ip_output_if() - * - * @return ERR_RTE if no route is found - * see ip_output_if() for more return values - */ -err_t -ip_output_hinted(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest, - u8_t ttl, u8_t tos, u8_t proto, u8_t *addr_hint) -{ - struct netif *netif; - err_t err; - - /* pbufs passed to IP must have a ref-count of 1 as their payload pointer - gets altered as the packet is passed down the stack */ - LWIP_ASSERT("p->ref == 1", p->ref == 1); - - if ((netif = ip_route(dest)) == NULL) { - LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", - ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest))); - IP_STATS_INC(ip.rterr); - return ERR_RTE; - } - - netif->addr_hint = addr_hint; - err = ip_output_if(p, src, dest, ttl, tos, proto, netif); - netif->addr_hint = NULL; - - return err; -} -#endif /* LWIP_NETIF_HWADDRHINT*/ - -#if IP_DEBUG -/* Print an IP header by using LWIP_DEBUGF - * @param p an IP packet, p->payload pointing to the IP header - */ -void -ip_debug_print(struct pbuf *p) -{ - struct ip_hdr *iphdr = (struct ip_hdr *)p->payload; - u8_t *payload; - - payload = (u8_t *)iphdr + IP_HLEN; - - LWIP_DEBUGF(IP_DEBUG, ("IP header:\n")); - LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n")); - LWIP_DEBUGF(IP_DEBUG, ("|%2"S16_F" |%2"S16_F" | 0x%02"X16_F" | %5"U16_F" | (v, hl, tos, len)\n", - IPH_V(iphdr), - IPH_HL(iphdr), - IPH_TOS(iphdr), - ntohs(IPH_LEN(iphdr)))); - LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n")); - LWIP_DEBUGF(IP_DEBUG, ("| %5"U16_F" |%"U16_F"%"U16_F"%"U16_F"| %4"U16_F" | (id, flags, offset)\n", - ntohs(IPH_ID(iphdr)), - ntohs(IPH_OFFSET(iphdr)) >> 15 & 1, - ntohs(IPH_OFFSET(iphdr)) >> 14 & 1, - ntohs(IPH_OFFSET(iphdr)) >> 13 & 1, - ntohs(IPH_OFFSET(iphdr)) & IP_OFFMASK)); - LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n")); - LWIP_DEBUGF(IP_DEBUG, ("| %3"U16_F" | %3"U16_F" | 0x%04"X16_F" | (ttl, proto, chksum)\n", - IPH_TTL(iphdr), - IPH_PROTO(iphdr), - ntohs(IPH_CHKSUM(iphdr)))); - LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n")); - LWIP_DEBUGF(IP_DEBUG, ("| %3"U16_F" | %3"U16_F" | %3"U16_F" | %3"U16_F" | (src)\n", - ip4_addr1_16(&iphdr->src), - ip4_addr2_16(&iphdr->src), - ip4_addr3_16(&iphdr->src), - ip4_addr4_16(&iphdr->src))); - LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n")); - LWIP_DEBUGF(IP_DEBUG, ("| %3"U16_F" | %3"U16_F" | %3"U16_F" | %3"U16_F" | (dest)\n", - ip4_addr1_16(&iphdr->dest), - ip4_addr2_16(&iphdr->dest), - ip4_addr3_16(&iphdr->dest), - ip4_addr4_16(&iphdr->dest))); - LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n")); -} -#endif /* IP_DEBUG */