| /* |
| * Copyright (c) 2001-2003, Adam Dunkels. |
| * 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 uIP TCP/IP stack. |
| * |
| * |
| */ |
| |
| /** |
| * \file |
| * The uIP TCP/IP stack code. |
| * \author Adam Dunkels <adam@dunkels.com> |
| */ |
| |
| /** |
| * \addtogroup uip |
| * @{ |
| */ |
| |
| #define DEBUG_PRINTF(...) /*printf(__VA_ARGS__)*/ |
| |
| /* |
| * uIP is a small implementation of the IP, UDP and TCP protocols (as |
| * well as some basic ICMP stuff). The implementation couples the IP, |
| * UDP, TCP and the application layers very tightly. To keep the size |
| * of the compiled code down, this code frequently uses the goto |
| * statement. While it would be possible to break the uip_process() |
| * function into many smaller functions, this would increase the code |
| * size because of the overhead of parameter passing and the fact that |
| * the optimier would not be as efficient. |
| * |
| * The principle is that we have a small buffer, called the uip_buf, |
| * in which the device driver puts an incoming packet. The TCP/IP |
| * stack parses the headers in the packet, and calls the |
| * application. If the remote host has sent data to the application, |
| * this data is present in the uip_buf and the application read the |
| * data from there. It is up to the application to put this data into |
| * a byte stream if needed. The application will not be fed with data |
| * that is out of sequence. |
| * |
| * If the application whishes to send data to the peer, it should put |
| * its data into the uip_buf. The uip_appdata pointer points to the |
| * first available byte. The TCP/IP stack will calculate the |
| * checksums, and fill in the necessary header fields and finally send |
| * the packet back to the peer. |
| */ |
| |
| #include "contiki/ip/uip.h" |
| #include "contiki/ip/uipopt.h" |
| #include "contiki/ipv4/uip_arp.h" |
| |
| #include "contiki/ipv4/uip-neighbor.h" |
| |
| #ifdef CONFIG_NETWORK_IP_STACK_DEBUG_IPV4 |
| #define DEBUG 1 |
| #endif |
| #include "contiki/ip/uip-debug.h" |
| |
| #include <net/ip_buf.h> |
| #include <string.h> |
| #include <errno.h> |
| |
| #ifdef CONFIG_DHCP |
| #include "contiki/ip/dhcpc.h" |
| #endif |
| |
| extern void net_context_set_connection_status(struct net_context *context, |
| int status); |
| void *net_context_get_internal_connection(struct net_context *context); |
| void net_context_set_internal_connection(struct net_context *context, |
| void *conn); |
| struct net_context *net_context_find_internal_connection(void *conn); |
| void net_context_tcp_set_pending(struct net_context *context, |
| struct net_buf *buf); |
| |
| /*---------------------------------------------------------------------------*/ |
| /* Variable definitions. */ |
| |
| |
| /* The IP address of this host. If it is defined to be fixed (by |
| setting UIP_FIXEDADDR to 1 in uipopt.h), the address is set |
| here. Otherwise, the address */ |
| #if UIP_FIXEDADDR > 0 |
| const uip_ipaddr_t uip_hostaddr = |
| { UIP_IPADDR0, UIP_IPADDR1, UIP_IPADDR2, UIP_IPADDR3 }; |
| const uip_ipaddr_t uip_draddr = |
| { UIP_DRIPADDR0, UIP_DRIPADDR1, UIP_DRIPADDR2, UIP_DRIPADDR3 }; |
| const uip_ipaddr_t uip_netmask = |
| { UIP_NETMASK0, UIP_NETMASK1, UIP_NETMASK2, UIP_NETMASK3 }; |
| #else |
| uip_ipaddr_t uip_hostaddr, uip_draddr, uip_netmask; |
| #endif /* UIP_FIXEDADDR */ |
| |
| const uip_ipaddr_t uip_broadcast_addr = |
| #if NETSTACK_CONF_WITH_IPV6 |
| { { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, |
| 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff } }; |
| #else /* NETSTACK_CONF_WITH_IPV6 */ |
| { { 0xff, 0xff, 0xff, 0xff } }; |
| #endif /* NETSTACK_CONF_WITH_IPV6 */ |
| const uip_ipaddr_t uip_all_zeroes_addr = { { 0x0, /* rest is 0 */ } }; |
| |
| #if UIP_FIXEDETHADDR |
| const uip_lladdr_t uip_lladdr = {{UIP_ETHADDR0, |
| UIP_ETHADDR1, |
| UIP_ETHADDR2, |
| UIP_ETHADDR3, |
| UIP_ETHADDR4, |
| UIP_ETHADDR5}}; |
| #else |
| uip_lladdr_t uip_lladdr = {{0,0,0,0,0,0}}; |
| #endif |
| |
| #if 0 |
| /* These are moved to net_buf.h */ |
| /* The packet buffer that contains incoming packets. */ |
| uip_buf_t uip_aligned_buf; |
| |
| void *uip_appdata; /* The uip_appdata pointer points to |
| application data. */ |
| void *uip_sappdata; /* The uip_appdata pointer points to |
| the application data which is to |
| be sent. */ |
| #if UIP_URGDATA > 0 |
| void *uip_urgdata; /* The uip_urgdata pointer points to |
| urgent data (out-of-band data), if |
| present. */ |
| uint16_t uip_urglen, uip_surglen; |
| #endif /* UIP_URGDATA > 0 */ |
| |
| uint16_t uip_len, uip_slen; |
| /* The uip_len is either 8 or 16 bits, |
| depending on the maximum packet |
| size. */ |
| |
| uint8_t uip_flags; /* The uip_flags variable is used for |
| communication between the TCP/IP stack |
| and the application program. */ |
| struct uip_conn *uip_conn; /* uip_conn always points to the current |
| connection. */ |
| #endif /* 0 */ |
| |
| struct uip_conn uip_conns[UIP_CONNS]; |
| /* The uip_conns array holds all TCP |
| connections. */ |
| uint16_t uip_listenports[UIP_LISTENPORTS]; |
| /* The uip_listenports list all currently |
| listning ports. */ |
| #if UIP_UDP |
| #if 0 |
| /* Moved to net_buf */ |
| struct uip_udp_conn *uip_udp_conn; |
| #endif /* 0 */ |
| struct uip_udp_conn uip_udp_conns[UIP_UDP_CONNS]; |
| #endif /* UIP_UDP */ |
| |
| static uint16_t ipid; /* Ths ipid variable is an increasing |
| number that is used for the IP ID |
| field. */ |
| |
| void uip_setipid(uint16_t id) { ipid = id; } |
| |
| static uint8_t iss[4]; /* The iss variable is used for the TCP |
| initial sequence number. */ |
| |
| #if UIP_ACTIVE_OPEN || UIP_UDP |
| static uint16_t lastport; /* Keeps track of the last port used for |
| a new connection. */ |
| #endif /* UIP_ACTIVE_OPEN || UIP_UDP */ |
| |
| /* Temporary variables. */ |
| uint8_t uip_acc32[4]; |
| static uint8_t c; |
| #if UIP_TCP |
| static uint8_t opt; |
| static uint16_t tmp16; |
| #endif /* UIP_TCP */ |
| |
| /* Structures and definitions. */ |
| #define TCP_FIN 0x01 |
| #define TCP_SYN 0x02 |
| #define TCP_RST 0x04 |
| #define TCP_PSH 0x08 |
| #define TCP_ACK 0x10 |
| #define TCP_URG 0x20 |
| #define TCP_CTL 0x3f |
| |
| #define TCP_OPT_END 0 /* End of TCP options list */ |
| #define TCP_OPT_NOOP 1 /* "No-operation" TCP option */ |
| #define TCP_OPT_MSS 2 /* Maximum segment size TCP option */ |
| |
| #define TCP_OPT_MSS_LEN 4 /* Length of TCP MSS option. */ |
| |
| #define ICMP_ECHO_REPLY 0 |
| #define ICMP_ECHO 8 |
| |
| #define ICMP_DEST_UNREACHABLE 3 |
| #define ICMP_PORT_UNREACHABLE 3 |
| |
| #define ICMP6_ECHO_REPLY 129 |
| #define ICMP6_ECHO 128 |
| #define ICMP6_NEIGHBOR_SOLICITATION 135 |
| #define ICMP6_NEIGHBOR_ADVERTISEMENT 136 |
| |
| #define ICMP6_FLAG_S (1 << 6) |
| |
| #define ICMP6_OPTION_SOURCE_LINK_ADDRESS 1 |
| #define ICMP6_OPTION_TARGET_LINK_ADDRESS 2 |
| |
| |
| /* Macros. */ |
| #define BUF(buf) ((struct uip_tcpip_hdr *)&uip_buf(buf)[UIP_LLH_LEN]) |
| #define FBUF ((struct uip_tcpip_hdr *)&uip_reassbuf[0]) |
| #define ICMPBUF(buf) ((struct uip_icmpip_hdr *)&uip_buf(buf)[UIP_LLH_LEN]) |
| #define UDPBUF(buf) ((struct uip_udpip_hdr *)&uip_buf(buf)[UIP_LLH_LEN]) |
| |
| |
| #if UIP_STATISTICS == 1 |
| struct uip_stats uip_stat; |
| #define UIP_STAT(s) s |
| #else |
| #define UIP_STAT(s) |
| #endif /* UIP_STATISTICS == 1 */ |
| |
| #if UIP_LOGGING == 1 |
| #include <stdio.h> |
| void uip_log(char *msg); |
| #define UIP_LOG(m) uip_log(m) |
| #else |
| #define UIP_LOG(m) |
| #endif /* UIP_LOGGING == 1 */ |
| |
| #if ! UIP_ARCH_ADD32 |
| void |
| uip_add32(uint8_t *op32, uint16_t op16) |
| { |
| uip_acc32[3] = op32[3] + (op16 & 0xff); |
| uip_acc32[2] = op32[2] + (op16 >> 8); |
| uip_acc32[1] = op32[1]; |
| uip_acc32[0] = op32[0]; |
| |
| if(uip_acc32[2] < (op16 >> 8)) { |
| ++uip_acc32[1]; |
| if(uip_acc32[1] == 0) { |
| ++uip_acc32[0]; |
| } |
| } |
| |
| |
| if(uip_acc32[3] < (op16 & 0xff)) { |
| ++uip_acc32[2]; |
| if(uip_acc32[2] == 0) { |
| ++uip_acc32[1]; |
| if(uip_acc32[1] == 0) { |
| ++uip_acc32[0]; |
| } |
| } |
| } |
| } |
| |
| #endif /* UIP_ARCH_ADD32 */ |
| |
| #if ! UIP_ARCH_CHKSUM |
| /*---------------------------------------------------------------------------*/ |
| static uint16_t |
| chksum(uint16_t sum, const uint8_t *data, uint16_t len) |
| { |
| uint16_t t; |
| const uint8_t *dataptr; |
| const uint8_t *last_byte; |
| |
| dataptr = data; |
| last_byte = data + len - 1; |
| |
| while(dataptr < last_byte) { /* At least two more bytes */ |
| t = (dataptr[0] << 8) + dataptr[1]; |
| sum += t; |
| if(sum < t) { |
| sum++; /* carry */ |
| } |
| dataptr += 2; |
| } |
| |
| if(dataptr == last_byte) { |
| t = (dataptr[0] << 8) + 0; |
| sum += t; |
| if(sum < t) { |
| sum++; /* carry */ |
| } |
| } |
| |
| /* Return sum in host byte order. */ |
| return sum; |
| } |
| /*---------------------------------------------------------------------------*/ |
| uint16_t |
| uip_chksum(uint16_t *data, uint16_t len) |
| { |
| return uip_htons(chksum(0, (uint8_t *)data, len)); |
| } |
| /*---------------------------------------------------------------------------*/ |
| #ifndef UIP_ARCH_IPCHKSUM |
| uint16_t |
| uip_ipchksum(struct net_buf *buf) |
| { |
| uint16_t sum; |
| |
| sum = chksum(0, &uip_buf(buf)[UIP_LLH_LEN], UIP_IPH_LEN); |
| DEBUG_PRINTF("uip_ipchksum: sum 0x%04x\n", sum); |
| return (sum == 0) ? 0xffff : uip_htons(sum); |
| } |
| #endif |
| /*---------------------------------------------------------------------------*/ |
| static uint16_t |
| upper_layer_chksum(struct net_buf *buf, uint8_t proto) |
| { |
| uint16_t upper_layer_len; |
| uint16_t sum; |
| |
| #if NETSTACK_CONF_WITH_IPV6 |
| upper_layer_len = (((uint16_t)(BUF->len[0]) << 8) + BUF->len[1]); |
| #else /* NETSTACK_CONF_WITH_IPV6 */ |
| upper_layer_len = (((uint16_t)(BUF(buf)->len[0]) << 8) + BUF(buf)->len[1]) - UIP_IPH_LEN; |
| #endif /* NETSTACK_CONF_WITH_IPV6 */ |
| |
| /* First sum pseudoheader. */ |
| |
| /* IP protocol and length fields. This addition cannot carry. */ |
| sum = upper_layer_len + proto; |
| /* Sum IP source and destination addresses. */ |
| sum = chksum(sum, (uint8_t *)&BUF(buf)->srcipaddr, 2 * sizeof(uip_ipaddr_t)); |
| |
| /* Sum TCP header and data. */ |
| sum = chksum(sum, &uip_buf(buf)[UIP_IPH_LEN + UIP_LLH_LEN], |
| upper_layer_len); |
| |
| return (sum == 0) ? 0xffff : uip_htons(sum); |
| } |
| /*---------------------------------------------------------------------------*/ |
| #if NETSTACK_CONF_WITH_IPV6 |
| uint16_t |
| uip_icmp6chksum(void) |
| { |
| return upper_layer_chksum(UIP_PROTO_ICMP6); |
| |
| } |
| #endif /* NETSTACK_CONF_WITH_IPV6 */ |
| /*---------------------------------------------------------------------------*/ |
| uint16_t |
| uip_tcpchksum(struct net_buf *buf) |
| { |
| return upper_layer_chksum(buf, UIP_PROTO_TCP); |
| } |
| /*---------------------------------------------------------------------------*/ |
| #if UIP_UDP_CHECKSUMS |
| uint16_t |
| uip_udpchksum(void) |
| { |
| return upper_layer_chksum(UIP_PROTO_UDP); |
| } |
| #endif /* UIP_UDP_CHECKSUMS */ |
| #endif /* UIP_ARCH_CHKSUM */ |
| /*---------------------------------------------------------------------------*/ |
| void |
| uip_init(void) |
| { |
| for(c = 0; c < UIP_LISTENPORTS; ++c) { |
| uip_listenports[c] = 0; |
| } |
| for(c = 0; c < UIP_CONNS; ++c) { |
| uip_conns[c].tcpstateflags = UIP_CLOSED; |
| } |
| #if UIP_ACTIVE_OPEN || UIP_UDP |
| lastport = 1024; |
| #endif /* UIP_ACTIVE_OPEN || UIP_UDP */ |
| |
| #if UIP_UDP |
| for(c = 0; c < UIP_UDP_CONNS; ++c) { |
| uip_udp_conns[c].lport = 0; |
| } |
| #endif /* UIP_UDP */ |
| |
| |
| /* IPv4 initialization. */ |
| #if UIP_FIXEDADDR == 0 |
| /* uip_hostaddr[0] = uip_hostaddr[1] = 0;*/ |
| #endif /* UIP_FIXEDADDR */ |
| |
| } |
| /*---------------------------------------------------------------------------*/ |
| #if UIP_ACTIVE_OPEN |
| struct uip_conn * |
| uip_connect(const uip_ipaddr_t *ripaddr, uint16_t rport) |
| { |
| register struct uip_conn *conn, *cconn; |
| |
| /* Find an unused local port. */ |
| again: |
| ++lastport; |
| |
| if(lastport >= 32000) { |
| lastport = 4096; |
| } |
| |
| /* Check if this port is already in use, and if so try to find |
| another one. */ |
| for(c = 0; c < UIP_CONNS; ++c) { |
| conn = &uip_conns[c]; |
| if(conn->tcpstateflags != UIP_CLOSED && |
| conn->lport == uip_htons(lastport)) { |
| goto again; |
| } |
| } |
| |
| conn = 0; |
| for(c = 0; c < UIP_CONNS; ++c) { |
| cconn = &uip_conns[c]; |
| if(cconn->tcpstateflags == UIP_CLOSED) { |
| conn = cconn; |
| break; |
| } |
| if(cconn->tcpstateflags == UIP_TIME_WAIT) { |
| if(conn == 0 || |
| cconn->timer > conn->timer) { |
| conn = cconn; |
| } |
| } |
| } |
| |
| if(conn == 0) { |
| return 0; |
| } |
| |
| conn->tcpstateflags = UIP_SYN_SENT; |
| |
| conn->snd_nxt[0] = iss[0]; |
| conn->snd_nxt[1] = iss[1]; |
| conn->snd_nxt[2] = iss[2]; |
| conn->snd_nxt[3] = iss[3]; |
| |
| conn->initialmss = conn->mss = UIP_TCP_MSS; |
| |
| conn->len = 1; /* TCP length of the SYN is one. */ |
| conn->nrtx = 0; |
| conn->timer = 1; /* Send the SYN next time around. */ |
| conn->rto = UIP_RTO; |
| conn->sa = 0; |
| conn->sv = 16; /* Initial value of the RTT variance. */ |
| conn->lport = uip_htons(lastport); |
| conn->rport = rport; |
| uip_ipaddr_copy(&conn->ripaddr, ripaddr); |
| |
| return conn; |
| } |
| #endif /* UIP_ACTIVE_OPEN */ |
| /*---------------------------------------------------------------------------*/ |
| #if UIP_UDP |
| struct uip_udp_conn * |
| uip_udp_new(const uip_ipaddr_t *ripaddr, uint16_t rport) |
| { |
| register struct uip_udp_conn *conn; |
| |
| /* Find an unused local port. */ |
| again: |
| ++lastport; |
| |
| if(lastport >= 32000) { |
| lastport = 4096; |
| } |
| |
| for(c = 0; c < UIP_UDP_CONNS; ++c) { |
| if(uip_udp_conns[c].lport == uip_htons(lastport)) { |
| goto again; |
| } |
| } |
| |
| |
| conn = 0; |
| for(c = 0; c < UIP_UDP_CONNS; ++c) { |
| if(uip_udp_conns[c].lport == 0) { |
| conn = &uip_udp_conns[c]; |
| break; |
| } |
| } |
| |
| if(conn == 0) { |
| return 0; |
| } |
| |
| conn->lport = UIP_HTONS(lastport); |
| conn->rport = rport; |
| if(ripaddr == NULL) { |
| memset(&conn->ripaddr, 0, sizeof(uip_ipaddr_t)); |
| } else { |
| uip_ipaddr_copy(&conn->ripaddr, ripaddr); |
| } |
| conn->ttl = UIP_TTL; |
| |
| return conn; |
| } |
| #endif /* UIP_UDP */ |
| /*---------------------------------------------------------------------------*/ |
| void |
| uip_unlisten(uint16_t port) |
| { |
| for(c = 0; c < UIP_LISTENPORTS; ++c) { |
| if(uip_listenports[c] == port) { |
| uip_listenports[c] = 0; |
| return; |
| } |
| } |
| } |
| /*---------------------------------------------------------------------------*/ |
| void |
| uip_listen(uint16_t port) |
| { |
| for(c = 0; c < UIP_LISTENPORTS; ++c) { |
| if(uip_listenports[c] == 0) { |
| uip_listenports[c] = port; |
| return; |
| } |
| } |
| } |
| /*---------------------------------------------------------------------------*/ |
| /* XXX: IP fragment reassembly: not well-tested. */ |
| |
| #if UIP_REASSEMBLY && !NETSTACK_CONF_WITH_IPV6 |
| #define UIP_REASS_BUFSIZE (UIP_BUFSIZE - UIP_LLH_LEN) |
| static uint8_t uip_reassbuf[UIP_REASS_BUFSIZE]; |
| static uint8_t uip_reassbitmap[UIP_REASS_BUFSIZE / (8 * 8)]; |
| static const uint8_t bitmap_bits[8] = {0xff, 0x7f, 0x3f, 0x1f, |
| 0x0f, 0x07, 0x03, 0x01}; |
| static uint16_t uip_reasslen; |
| static uint8_t uip_reassflags; |
| #define UIP_REASS_FLAG_LASTFRAG 0x01 |
| static uint8_t uip_reasstmr; |
| |
| #define IP_MF 0x20 |
| |
| static uint8_t |
| uip_reass(void) |
| { |
| uint16_t offset, len; |
| uint16_t i; |
| |
| /* If ip_reasstmr is zero, no packet is present in the buffer, so we |
| write the IP header of the fragment into the reassembly |
| buffer. The timer is updated with the maximum age. */ |
| if(uip_reasstmr == 0) { |
| memcpy(uip_reassbuf, &BUF->vhl, UIP_IPH_LEN); |
| uip_reasstmr = UIP_REASS_MAXAGE; |
| uip_reassflags = 0; |
| /* Clear the bitmap. */ |
| memset(uip_reassbitmap, 0, sizeof(uip_reassbitmap)); |
| } |
| |
| /* Check if the incoming fragment matches the one currently present |
| in the reasembly buffer. If so, we proceed with copying the |
| fragment into the buffer. */ |
| if(BUF->srcipaddr[0] == FBUF->srcipaddr[0] && |
| BUF->srcipaddr[1] == FBUF->srcipaddr[1] && |
| BUF->destipaddr[0] == FBUF->destipaddr[0] && |
| BUF->destipaddr[1] == FBUF->destipaddr[1] && |
| BUF->ipid[0] == FBUF->ipid[0] && |
| BUF->ipid[1] == FBUF->ipid[1]) { |
| |
| len = (BUF->len[0] << 8) + BUF->len[1] - (BUF->vhl & 0x0f) * 4; |
| offset = (((BUF->ipoffset[0] & 0x3f) << 8) + BUF->ipoffset[1]) * 8; |
| |
| /* If the offset or the offset + fragment length overflows the |
| reassembly buffer, we discard the entire packet. */ |
| if(offset > UIP_REASS_BUFSIZE || |
| offset + len > UIP_REASS_BUFSIZE) { |
| uip_reasstmr = 0; |
| goto nullreturn; |
| } |
| |
| /* Copy the fragment into the reassembly buffer, at the right |
| offset. */ |
| memcpy(&uip_reassbuf[UIP_IPH_LEN + offset], |
| (char *)BUF + (int)((BUF->vhl & 0x0f) * 4), |
| len); |
| |
| /* Update the bitmap. */ |
| if(offset / (8 * 8) == (offset + len) / (8 * 8)) { |
| /* If the two endpoints are in the same byte, we only update |
| that byte. */ |
| |
| uip_reassbitmap[offset / (8 * 8)] |= |
| bitmap_bits[(offset / 8 ) & 7] & |
| ~bitmap_bits[((offset + len) / 8 ) & 7]; |
| } else { |
| /* If the two endpoints are in different bytes, we update the |
| bytes in the endpoints and fill the stuff inbetween with |
| 0xff. */ |
| uip_reassbitmap[offset / (8 * 8)] |= |
| bitmap_bits[(offset / 8 ) & 7]; |
| for(i = 1 + offset / (8 * 8); i < (offset + len) / (8 * 8); ++i) { |
| uip_reassbitmap[i] = 0xff; |
| } |
| uip_reassbitmap[(offset + len) / (8 * 8)] |= |
| ~bitmap_bits[((offset + len) / 8 ) & 7]; |
| } |
| |
| /* If this fragment has the More Fragments flag set to zero, we |
| know that this is the last fragment, so we can calculate the |
| size of the entire packet. We also set the |
| IP_REASS_FLAG_LASTFRAG flag to indicate that we have received |
| the final fragment. */ |
| |
| if((BUF->ipoffset[0] & IP_MF) == 0) { |
| uip_reassflags |= UIP_REASS_FLAG_LASTFRAG; |
| uip_reasslen = offset + len; |
| } |
| |
| /* Finally, we check if we have a full packet in the buffer. We do |
| this by checking if we have the last fragment and if all bits |
| in the bitmap are set. */ |
| if(uip_reassflags & UIP_REASS_FLAG_LASTFRAG) { |
| /* Check all bytes up to and including all but the last byte in |
| the bitmap. */ |
| for(i = 0; i < uip_reasslen / (8 * 8) - 1; ++i) { |
| if(uip_reassbitmap[i] != 0xff) { |
| goto nullreturn; |
| } |
| } |
| /* Check the last byte in the bitmap. It should contain just the |
| right amount of bits. */ |
| if(uip_reassbitmap[uip_reasslen / (8 * 8)] != |
| (uint8_t)~bitmap_bits[uip_reasslen / 8 & 7]) { |
| goto nullreturn; |
| } |
| |
| /* If we have come this far, we have a full packet in the |
| buffer, so we allocate a pbuf and copy the packet into it. We |
| also reset the timer. */ |
| uip_reasstmr = 0; |
| memcpy(BUF, FBUF, uip_reasslen); |
| |
| /* Pretend to be a "normal" (i.e., not fragmented) IP packet |
| from now on. */ |
| BUF->ipoffset[0] = BUF->ipoffset[1] = 0; |
| BUF->len[0] = uip_reasslen >> 8; |
| BUF->len[1] = uip_reasslen & 0xff; |
| BUF->ipchksum = 0; |
| BUF->ipchksum = ~(uip_ipchksum()); |
| |
| return uip_reasslen; |
| } |
| } |
| |
| nullreturn: |
| return 0; |
| } |
| #endif /* UIP_REASSEMBLY */ |
| /*---------------------------------------------------------------------------*/ |
| #if UIP_TCP |
| static void |
| uip_add_rcv_nxt(struct net_buf *buf, uint16_t n) |
| { |
| uip_add32(uip_conn(buf)->rcv_nxt, n); |
| uip_conn(buf)->rcv_nxt[0] = uip_acc32[0]; |
| uip_conn(buf)->rcv_nxt[1] = uip_acc32[1]; |
| uip_conn(buf)->rcv_nxt[2] = uip_acc32[2]; |
| uip_conn(buf)->rcv_nxt[3] = uip_acc32[3]; |
| } |
| #endif /* UIP_TCP */ |
| |
| #if UIP_TCP |
| static inline void handle_tcp_retransmit_timer(struct net_buf *not_used, |
| void *ptr) |
| { |
| struct uip_conn *conn = ptr; |
| |
| PRINTF("%s: connection %p buf %p\n", __func__, conn, conn ? conn->buf : 0); |
| if (conn && conn->buf) { |
| conn->timer = 0; |
| if (uip_process(&conn->buf, UIP_TIMER)) { |
| tcpip_resend_syn(conn, conn->buf); |
| } |
| } |
| } |
| |
| static inline void tcp_set_retrans_timer(struct uip_conn *conn) |
| { |
| ctimer_set(NULL, &conn->retransmit_timer, CLOCK_SECOND, |
| &handle_tcp_retransmit_timer, conn); |
| } |
| |
| static inline void tcp_cancel_retrans_timer(struct uip_conn *conn) |
| { |
| ctimer_stop(&conn->retransmit_timer); |
| } |
| #endif /* UIP_TCP */ |
| /*---------------------------------------------------------------------------*/ |
| uint8_t |
| uip_process(struct net_buf **buf_out, uint8_t flag) |
| { |
| struct net_buf *buf = *buf_out; |
| #if UIP_TCP |
| register struct uip_conn *uip_connr = uip_conn(buf); |
| #endif |
| |
| #if UIP_UDP |
| int i; |
| if(flag == UIP_UDP_SEND_CONN) { |
| goto udp_send; |
| } |
| #endif /* UIP_UDP */ |
| #if UIP_TCP |
| if(flag != UIP_TCP_SEND_CONN) { |
| #endif |
| uip_sappdata(buf) = uip_appdata(buf) = &uip_buf(buf)[UIP_IPTCPH_LEN + UIP_LLH_LEN]; |
| #if UIP_TCP |
| } |
| #endif |
| /* Check if we were invoked because of a poll request for a |
| particular connection. */ |
| #if UIP_TCP |
| if(flag == UIP_POLL_REQUEST || flag == UIP_TCP_SEND_CONN) { |
| |
| /* If the connection is not found, and we are initiating the |
| * connection, try to get it. |
| */ |
| if (!uip_connr) { |
| uip_connr = net_context_get_internal_connection(ip_buf_context(buf)); |
| if (!uip_connr) { |
| PRINTF("No matching connection found for buf %p\n", buf); |
| ip_buf_sent_status(buf) = -ENOTCONN; |
| return 0; |
| } else { |
| uip_set_conn(buf) = uip_connr; |
| PRINTF("Using connection %p for buf %p\n", uip_conn(buf), buf); |
| } |
| } |
| |
| if((uip_connr->tcpstateflags & UIP_TS_MASK) == UIP_ESTABLISHED && |
| !uip_outstanding(uip_connr)) { |
| if (flag == UIP_POLL) { |
| uip_flags(buf) = UIP_POLL; |
| } |
| UIP_APPCALL(buf); |
| goto appsend; |
| #if UIP_ACTIVE_OPEN |
| } else if((uip_connr->tcpstateflags & UIP_TS_MASK) == UIP_SYN_SENT) { |
| if (uip_connr->nrtx > UIP_MAXSYNRTX) { |
| /* SYN has been sent too many times, just stop the connection. |
| */ |
| PRINTF("Too many SYN sent, dropping connection %p\n", uip_connr); |
| net_context_set_connection_status(ip_buf_context(buf), -ETIMEDOUT); |
| goto drop; |
| } |
| |
| /* In the SYN_SENT state, we retransmit out SYN. */ |
| BUF(buf)->flags = 0; |
| goto tcp_send_syn; |
| #endif /* UIP_ACTIVE_OPEN */ |
| } |
| if (flag == UIP_TCP_SEND_CONN) { |
| switch (uip_connr->tcpstateflags & UIP_TS_MASK) { |
| case UIP_CLOSED: |
| case UIP_FIN_WAIT_1: |
| case UIP_FIN_WAIT_2: |
| case UIP_CLOSING: |
| case UIP_TIME_WAIT: |
| ip_buf_sent_status(buf) = -ECONNABORTED; |
| goto drop; |
| } |
| if (uip_outstanding(uip_connr)) { |
| ip_buf_sent_status(buf) = -EAGAIN; |
| PRINTF("Retry to send packet len %d, outstanding data len %d, " |
| "conn %p\n", uip_len(buf), uip_outstanding(uip_connr), |
| uip_connr); |
| flag = UIP_TIMER; |
| goto tcp_retry; |
| } |
| } |
| goto drop; |
| } |
| #else /* TCP */ |
| if(flag == UIP_POLL_REQUEST) { |
| goto drop; |
| } |
| #endif /* UIP_TCP */ |
| |
| /* Check if we were invoked because of the periodic timer firing. */ |
| if(flag == UIP_TIMER) { |
| #if UIP_REASSEMBLY |
| if(uip_reasstmr != 0) { |
| --uip_reasstmr; |
| } |
| #endif /* UIP_REASSEMBLY */ |
| |
| #if UIP_TCP |
| /* Increase the initial sequence number. */ |
| if(++iss[3] == 0) { |
| if(++iss[2] == 0) { |
| if(++iss[1] == 0) { |
| ++iss[0]; |
| } |
| } |
| } |
| |
| /* Reset the length variables. */ |
| uip_len(buf) = 0; |
| uip_slen(buf) = 0; |
| tcp_retry: |
| /* Check if the connection is in a state in which we simply wait |
| for the connection to time out. If so, we increase the |
| connection's timer and remove the connection if it times |
| out. */ |
| if(uip_connr->tcpstateflags == UIP_TIME_WAIT || |
| uip_connr->tcpstateflags == UIP_FIN_WAIT_2) { |
| ++(uip_connr->timer); |
| if(uip_connr->timer == UIP_TIME_WAIT_TIMEOUT) { |
| uip_connr->tcpstateflags = UIP_CLOSED; |
| } |
| } else if(uip_connr->tcpstateflags != UIP_CLOSED) { |
| if (!uip_connr->buf) { |
| /* There cannot be any data pending if buf is NULL */ |
| uip_outstanding(uip_connr) = 0; |
| } |
| |
| /* If the connection has outstanding data, we increase the |
| connection's timer and see if it has reached the RTO value |
| in which case we retransmit. */ |
| |
| if(uip_outstanding(uip_connr)) { |
| if(uip_connr->timer-- == 0) { |
| if(uip_connr->nrtx == UIP_MAXRTX || |
| ((uip_connr->tcpstateflags == UIP_SYN_SENT || |
| uip_connr->tcpstateflags == UIP_SYN_RCVD) && |
| uip_connr->nrtx == UIP_MAXSYNRTX)) { |
| uip_connr->tcpstateflags = UIP_CLOSED; |
| |
| /* We call UIP_APPCALL() with uip_flags set to |
| UIP_TIMEDOUT to inform the application that the |
| connection has timed out. */ |
| uip_flags(buf) = UIP_TIMEDOUT; |
| UIP_APPCALL(buf); |
| |
| /* We also send a reset packet to the remote host. */ |
| BUF(buf)->flags = TCP_RST | TCP_ACK; |
| goto tcp_send_nodata; |
| } |
| |
| /* Exponential backoff. */ |
| uip_connr->timer = UIP_RTO << (uip_connr->nrtx > 4? |
| 4: |
| uip_connr->nrtx); |
| ++(uip_connr->nrtx); |
| |
| /* Ok, so we need to retransmit. We do this differently |
| depending on which state we are in. In ESTABLISHED, we |
| call upon the application so that it may prepare the |
| data for the retransmit. In SYN_RCVD, we resend the |
| SYNACK that we sent earlier and in LAST_ACK we have to |
| retransmit our FINACK. */ |
| UIP_STAT(++uip_stat.tcp.rexmit); |
| switch(uip_connr->tcpstateflags & UIP_TS_MASK) { |
| case UIP_SYN_RCVD: |
| /* In the SYN_RCVD state, we should retransmit our |
| SYNACK. */ |
| goto tcp_send_synack; |
| |
| #if UIP_ACTIVE_OPEN |
| case UIP_SYN_SENT: |
| /* In the SYN_SENT state, we retransmit out SYN. */ |
| BUF(buf)->flags = 0; |
| goto tcp_send_syn; |
| #endif /* UIP_ACTIVE_OPEN */ |
| |
| case UIP_ESTABLISHED: |
| /* In the ESTABLISHED state, we call upon the application |
| to do the actual retransmit after which we jump into |
| the code for sending out the packet (the apprexmit |
| label). */ |
| uip_flags(buf) = UIP_REXMIT; |
| UIP_APPCALL(buf); |
| goto apprexmit; |
| |
| case UIP_FIN_WAIT_1: |
| case UIP_CLOSING: |
| case UIP_LAST_ACK: |
| /* In all these states we should retransmit a FINACK. */ |
| goto tcp_send_finack; |
| |
| } |
| } |
| } else if((uip_connr->tcpstateflags & UIP_TS_MASK) == UIP_ESTABLISHED) { |
| /* If there was no need for a retransmission, we poll the |
| application for new data. */ |
| uip_flags(buf) = UIP_POLL; |
| UIP_APPCALL(buf); |
| goto appsend; |
| } |
| } |
| #endif |
| goto drop; |
| } |
| #if UIP_UDP |
| if(flag == UIP_UDP_TIMER) { |
| if(uip_udp_conn(buf)->lport != 0) { |
| uip_set_conn(buf) = NULL; |
| uip_sappdata(buf) = uip_appdata(buf) = &uip_buf(buf)[UIP_LLH_LEN + UIP_IPUDPH_LEN]; |
| uip_len(buf) = uip_slen(buf) = 0; |
| uip_flags(buf) = UIP_POLL; |
| UIP_UDP_APPCALL(buf); |
| goto udp_send; |
| } else { |
| goto drop; |
| } |
| } |
| #endif |
| |
| /* This is where the input processing starts. */ |
| UIP_STAT(++uip_stat.ip.recv); |
| |
| /* Start of IP input header processing code. */ |
| |
| #if NETSTACK_CONF_WITH_IPV6 |
| /* Check validity of the IP header. */ |
| if((BUF(buf)->vtc & 0xf0) != 0x60) { /* IP version and header length. */ |
| UIP_STAT(++uip_stat.ip.drop); |
| UIP_STAT(++uip_stat.ip.vhlerr); |
| UIP_LOG("ipv6: invalid version."); |
| goto drop; |
| } |
| #else /* NETSTACK_CONF_WITH_IPV6 */ |
| /* Check validity of the IP header. */ |
| if(BUF(buf)->vhl != 0x45) { /* IP version and header length. */ |
| UIP_STAT(++uip_stat.ip.drop); |
| UIP_STAT(++uip_stat.ip.vhlerr); |
| UIP_LOG("ip: invalid version or header length."); |
| goto drop; |
| } |
| #endif /* NETSTACK_CONF_WITH_IPV6 */ |
| |
| /* Check the size of the packet. If the size reported to us in |
| uip_len is smaller the size reported in the IP header, we assume |
| that the packet has been corrupted in transit. If the size of |
| uip_len is larger than the size reported in the IP packet header, |
| the packet has been padded and we set uip_len to the correct |
| value. */ |
| |
| if((BUF(buf)->len[0] << 8) + BUF(buf)->len[1] <= uip_len(buf)) { |
| uip_len(buf) = (BUF(buf)->len[0] << 8) + BUF(buf)->len[1]; |
| #if NETSTACK_CONF_WITH_IPV6 |
| uip_len += 40; /* The length reported in the IPv6 header is the |
| length of the payload that follows the |
| header. However, uIP uses the uip_len variable |
| for holding the size of the entire packet, |
| including the IP header. For IPv4 this is not a |
| problem as the length field in the IPv4 header |
| contains the length of the entire packet. But |
| for IPv6 we need to add the size of the IPv6 |
| header (40 bytes). */ |
| #endif /* NETSTACK_CONF_WITH_IPV6 */ |
| } else { |
| UIP_LOG("ip: packet shorter than reported in IP header."); |
| goto drop; |
| } |
| |
| #if !NETSTACK_CONF_WITH_IPV6 |
| /* Check the fragment flag. */ |
| if((BUF(buf)->ipoffset[0] & 0x3f) != 0 || |
| BUF(buf)->ipoffset[1] != 0) { |
| #if UIP_REASSEMBLY |
| uip_len = uip_reass(); |
| if(uip_len == 0) { |
| goto drop; |
| } |
| #else /* UIP_REASSEMBLY */ |
| UIP_STAT(++uip_stat.ip.drop); |
| UIP_STAT(++uip_stat.ip.fragerr); |
| UIP_LOG("ip: fragment dropped."); |
| goto drop; |
| #endif /* UIP_REASSEMBLY */ |
| } |
| #endif /* NETSTACK_CONF_WITH_IPV6 */ |
| |
| if(uip_ipaddr_cmp(&uip_hostaddr, &uip_all_zeroes_addr)) { |
| /* If we are configured to use ping IP address configuration and |
| haven't been assigned an IP address yet, we accept all ICMP |
| packets. */ |
| #if UIP_PINGADDRCONF && !NETSTACK_CONF_WITH_IPV6 |
| if(BUF->proto == UIP_PROTO_ICMP) { |
| UIP_LOG("ip: possible ping config packet received."); |
| goto icmp_input; |
| } else { |
| UIP_LOG("ip: packet dropped since no address assigned."); |
| goto drop; |
| } |
| #endif /* UIP_PINGADDRCONF */ |
| |
| } else { |
| /* If IP broadcast support is configured, we check for a broadcast |
| UDP packet, which may be destined to us. */ |
| #if UIP_BROADCAST |
| DEBUG_PRINTF("UDP IP checksum 0x%04x\n", uip_ipchksum()); |
| if(BUF->proto == UIP_PROTO_UDP && |
| (uip_ipaddr_cmp(&BUF->destipaddr, &uip_broadcast_addr) || |
| (BUF->destipaddr.u8[0] & 224) == 224)) { /* XXX this is a |
| hack to be able |
| to receive UDP |
| multicast |
| packets. We check |
| for the bit |
| pattern of the |
| multicast |
| prefix. */ |
| goto udp_input; |
| } |
| #endif /* UIP_BROADCAST */ |
| |
| /* Check if the packet is destined for our IP address. */ |
| #if !NETSTACK_CONF_WITH_IPV6 |
| #ifdef CONFIG_DHCP |
| /* DHCP message destination address in DHCP OFFER and ACK |
| * packets, destination address is 255.255.255.255, so skip |
| * addres comparison in this case |
| */ |
| if(BUF(buf)->proto == UIP_PROTO_UDP) { |
| uip_appdata(buf) = &uip_buf(buf)[UIP_LLH_LEN + UIP_IPUDPH_LEN]; |
| } |
| |
| if(msg_for_dhcpc(buf)) { |
| if(!(uip_ipaddr_cmp(&BUF(buf)->destipaddr, &uip_hostaddr) || |
| uip_ipaddr_cmp(&BUF(buf)->destipaddr, &uip_broadcast_addr))) { |
| UIP_STAT(++uip_stat.ip.drop); |
| goto drop; |
| } |
| } else |
| #endif |
| if(!uip_ipaddr_cmp(&BUF(buf)->destipaddr, &uip_hostaddr)) { |
| UIP_STAT(++uip_stat.ip.drop); |
| goto drop; |
| } |
| #else /* NETSTACK_CONF_WITH_IPV6 */ |
| /* For IPv6, packet reception is a little trickier as we need to |
| make sure that we listen to certain multicast addresses (all |
| hosts multicast address, and the solicited-node multicast |
| address) as well. However, we will cheat here and accept all |
| multicast packets that are sent to the ff02::/16 addresses. */ |
| if(!uip_ipaddr_cmp(&BUF->destipaddr, &uip_hostaddr) && |
| BUF->destipaddr.u16[0] != UIP_HTONS(0xff02)) { |
| UIP_STAT(++uip_stat.ip.drop); |
| goto drop; |
| } |
| #endif /* NETSTACK_CONF_WITH_IPV6 */ |
| } |
| |
| #if !NETSTACK_CONF_WITH_IPV6 |
| if(uip_ipchksum(buf) != 0xffff) { /* Compute and check the IP header |
| checksum. */ |
| UIP_STAT(++uip_stat.ip.drop); |
| UIP_STAT(++uip_stat.ip.chkerr); |
| UIP_LOG("ip: bad checksum."); |
| goto drop; |
| } |
| #endif /* NETSTACK_CONF_WITH_IPV6 */ |
| |
| #if UIP_TCP |
| if(BUF(buf)->proto == UIP_PROTO_TCP) { /* Check for TCP packet. If so, |
| proceed with TCP input |
| processing. */ |
| goto tcp_input; |
| } |
| #endif |
| |
| #if UIP_UDP |
| if(BUF(buf)->proto == UIP_PROTO_UDP) { |
| goto udp_input; |
| } |
| #endif /* UIP_UDP */ |
| |
| #if !NETSTACK_CONF_WITH_IPV6 |
| /* ICMPv4 processing code follows. */ |
| if(BUF(buf)->proto != UIP_PROTO_ICMP) { /* We only allow ICMP packets from |
| here. */ |
| UIP_STAT(++uip_stat.ip.drop); |
| UIP_STAT(++uip_stat.ip.protoerr); |
| UIP_LOG("ip: neither tcp nor icmp."); |
| goto drop; |
| } |
| |
| #if UIP_PINGADDRCONF |
| icmp_input: |
| #endif /* UIP_PINGADDRCONF */ |
| UIP_STAT(++uip_stat.icmp.recv); |
| |
| /* ICMP echo (i.e., ping) processing. This is simple, we only change |
| the ICMP type from ECHO to ECHO_REPLY and adjust the ICMP |
| checksum before we return the packet. */ |
| if(ICMPBUF(buf)->type != ICMP_ECHO) { |
| UIP_STAT(++uip_stat.icmp.drop); |
| UIP_STAT(++uip_stat.icmp.typeerr); |
| UIP_LOG("icmp: not icmp echo."); |
| goto drop; |
| } |
| |
| /* If we are configured to use ping IP address assignment, we use |
| the destination IP address of this ping packet and assign it to |
| ourself. */ |
| #if UIP_PINGADDRCONF |
| if(uip_ipaddr_cmp(&uip_hostaddr, &uip_all_zeroes_addr)) { |
| uip_hostaddr = BUF->destipaddr; |
| } |
| #endif /* UIP_PINGADDRCONF */ |
| |
| ICMPBUF(buf)->type = ICMP_ECHO_REPLY; |
| |
| if(ICMPBUF(buf)->icmpchksum >= UIP_HTONS(0xffff - (ICMP_ECHO << 8))) { |
| ICMPBUF(buf)->icmpchksum += UIP_HTONS(ICMP_ECHO << 8) + 1; |
| } else { |
| ICMPBUF(buf)->icmpchksum += UIP_HTONS(ICMP_ECHO << 8); |
| } |
| |
| /* Swap IP addresses. */ |
| uip_ipaddr_copy(&BUF(buf)->destipaddr, &BUF(buf)->srcipaddr); |
| uip_ipaddr_copy(&BUF(buf)->srcipaddr, &uip_hostaddr); |
| |
| UIP_STAT(++uip_stat.icmp.sent); |
| BUF(buf)->ttl = UIP_TTL; |
| goto ip_send_nolen; |
| |
| /* End of IPv4 input header processing code. */ |
| #else /* !NETSTACK_CONF_WITH_IPV6 */ |
| |
| /* This is IPv6 ICMPv6 processing code. */ |
| DEBUG_PRINTF("icmp6_input: length %d\n", uip_len); |
| |
| if(BUF->proto != UIP_PROTO_ICMP6) { /* We only allow ICMPv6 packets from |
| here. */ |
| UIP_STAT(++uip_stat.ip.drop); |
| UIP_STAT(++uip_stat.ip.protoerr); |
| UIP_LOG("ip: neither tcp nor icmp6."); |
| goto drop; |
| } |
| |
| UIP_STAT(++uip_stat.icmp.recv); |
| |
| /* If we get a neighbor solicitation for our address we should send |
| a neighbor advertisement message back. */ |
| if(ICMPBUF->type == ICMP6_NEIGHBOR_SOLICITATION) { |
| if(uip_ipaddr_cmp(&ICMPBUF->icmp6data, &uip_hostaddr)) { |
| |
| if(ICMPBUF->options[0] == ICMP6_OPTION_SOURCE_LINK_ADDRESS) { |
| /* Save the sender's address in our neighbor list. */ |
| uip_neighbor_add(&ICMPBUF->srcipaddr, &(ICMPBUF->options[2])); |
| } |
| |
| /* We should now send a neighbor advertisement back to where the |
| neighbor solicication came from. */ |
| ICMPBUF->type = ICMP6_NEIGHBOR_ADVERTISEMENT; |
| ICMPBUF->flags = ICMP6_FLAG_S; /* Solicited flag. */ |
| |
| ICMPBUF->reserved1 = ICMPBUF->reserved2 = ICMPBUF->reserved3 = 0; |
| |
| uip_ipaddr_copy(&ICMPBUF->destipaddr, &ICMPBUF->srcipaddr); |
| uip_ipaddr_copy(&ICMPBUF->srcipaddr, &uip_hostaddr); |
| ICMPBUF->options[0] = ICMP6_OPTION_TARGET_LINK_ADDRESS; |
| ICMPBUF->options[1] = 1; /* Options length, 1 = 8 bytes. */ |
| memcpy(&(ICMPBUF->options[2]), &uip_lladdr, sizeof(uip_lladdr)); |
| ICMPBUF->icmpchksum = 0; |
| ICMPBUF->icmpchksum = ~uip_icmp6chksum(); |
| |
| goto send; |
| |
| } |
| goto drop; |
| } else if(ICMPBUF->type == ICMP6_ECHO) { |
| /* ICMP echo (i.e., ping) processing. This is simple, we only |
| change the ICMP type from ECHO to ECHO_REPLY and update the |
| ICMP checksum before we return the packet. */ |
| |
| ICMPBUF->type = ICMP6_ECHO_REPLY; |
| |
| uip_ipaddr_copy(&BUF->destipaddr, &BUF->srcipaddr); |
| uip_ipaddr_copy(&BUF->srcipaddr, &uip_hostaddr); |
| ICMPBUF->icmpchksum = 0; |
| ICMPBUF->icmpchksum = ~uip_icmp6chksum(); |
| |
| UIP_STAT(++uip_stat.icmp.sent); |
| goto send; |
| } else { |
| DEBUG_PRINTF("Unknown icmp6 message type %d\n", ICMPBUF->type); |
| UIP_STAT(++uip_stat.icmp.drop); |
| UIP_STAT(++uip_stat.icmp.typeerr); |
| UIP_LOG("icmp: unknown ICMP message."); |
| goto drop; |
| } |
| |
| /* End of IPv6 ICMP processing. */ |
| |
| #endif /* !NETSTACK_CONF_WITH_IPV6 */ |
| |
| #if UIP_UDP |
| /* UDP input processing. */ |
| udp_input: |
| /* UDP processing is really just a hack. We don't do anything to the |
| UDP/IP headers, but let the UDP application do all the hard |
| work. If the application sets uip_slen, it has a packet to |
| send. */ |
| #if UIP_UDP_CHECKSUMS |
| uip_len = uip_len - UIP_IPUDPH_LEN; |
| uip_appdata = &uip_buf[UIP_LLH_LEN + UIP_IPUDPH_LEN]; |
| if(UDPBUF->udpchksum != 0 && uip_udpchksum() != 0xffff) { |
| UIP_STAT(++uip_stat.udp.drop); |
| UIP_STAT(++uip_stat.udp.chkerr); |
| UIP_LOG("udp: bad checksum."); |
| goto drop; |
| } |
| #else /* UIP_UDP_CHECKSUMS */ |
| uip_len(buf) = uip_len(buf) - UIP_IPUDPH_LEN; |
| #endif /* UIP_UDP_CHECKSUMS */ |
| |
| /* Make sure that the UDP destination port number is not zero. */ |
| if(UDPBUF(buf)->destport == 0) { |
| UIP_LOG("udp: zero port."); |
| goto drop; |
| } |
| |
| /* Demultiplex this UDP packet between the UDP "connections". */ |
| for(i = 0, uip_set_udp_conn(buf) = &uip_udp_conns[0]; |
| i < UIP_UDP_CONNS && uip_udp_conn(buf) < &uip_udp_conns[UIP_UDP_CONNS]; |
| i++, uip_set_udp_conn(buf) += sizeof(struct uip_udp_conn)) { |
| /* If the local UDP port is non-zero, the connection is considered |
| to be used. If so, the local port number is checked against the |
| destination port number in the received packet. If the two port |
| numbers match, the remote port number is checked if the |
| connection is bound to a remote port. Finally, if the |
| connection is bound to a remote IP address, the source IP |
| address of the packet is checked. */ |
| if(uip_udp_conn(buf)->lport != 0 && |
| UDPBUF(buf)->destport == uip_udp_conn(buf)->lport && |
| (uip_udp_conn(buf)->rport == 0 || |
| UDPBUF(buf)->srcport == uip_udp_conn(buf)->rport) && |
| (uip_ipaddr_cmp(&uip_udp_conn(buf)->ripaddr, &uip_all_zeroes_addr) || |
| uip_ipaddr_cmp(&uip_udp_conn(buf)->ripaddr, &uip_broadcast_addr) || |
| uip_ipaddr_cmp(&BUF(buf)->srcipaddr, &uip_udp_conn(buf)->ripaddr))) { |
| goto udp_found; |
| } |
| } |
| UIP_LOG("udp: no matching connection found"); |
| UIP_STAT(++uip_stat.udp.drop); |
| #if UIP_CONF_ICMP_DEST_UNREACH && !NETSTACK_CONF_WITH_IPV6 |
| /* Copy fields from packet header into payload of this ICMP packet. */ |
| memcpy(&(ICMPBUF->payload[0]), ICMPBUF, UIP_IPH_LEN + 8); |
| |
| /* Set the ICMP type and code. */ |
| ICMPBUF->type = ICMP_DEST_UNREACHABLE; |
| ICMPBUF->icode = ICMP_PORT_UNREACHABLE; |
| |
| /* Calculate the ICMP checksum. */ |
| ICMPBUF->icmpchksum = 0; |
| ICMPBUF->icmpchksum = ~uip_chksum((uint16_t *)&(ICMPBUF->type), 36); |
| |
| /* Set the IP destination address to be the source address of the |
| original packet. */ |
| uip_ipaddr_copy(&BUF->destipaddr, &BUF->srcipaddr); |
| |
| /* Set our IP address as the source address. */ |
| uip_ipaddr_copy(&BUF->srcipaddr, &uip_hostaddr); |
| |
| /* The size of the ICMP destination unreachable packet is 36 + the |
| size of the IP header (20) = 56. */ |
| uip_len = 36 + UIP_IPH_LEN; |
| ICMPBUF->len[0] = 0; |
| ICMPBUF->len[1] = (uint8_t)uip_len; |
| ICMPBUF->ttl = UIP_TTL; |
| ICMPBUF->proto = UIP_PROTO_ICMP; |
| |
| goto ip_send_nolen; |
| #else /* UIP_CONF_ICMP_DEST_UNREACH */ |
| goto drop; |
| #endif /* UIP_CONF_ICMP_DEST_UNREACH */ |
| |
| udp_found: |
| PRINTF("In udp_found\n"); |
| UIP_STAT(++uip_stat.udp.recv); |
| uip_set_conn(buf) = NULL; |
| uip_flags(buf) = UIP_NEWDATA; |
| uip_sappdata(buf) = uip_appdata(buf) = &uip_buf(buf)[UIP_LLH_LEN + UIP_IPUDPH_LEN]; |
| uip_slen(buf) = 0; |
| UIP_UDP_APPCALL(buf); |
| if(uip_slen(buf) == 0) { |
| /* If the application does not want to send anything, then uip_slen(buf) |
| * will be 0. In this case we MUST NOT set uip_len(buf) to 0 as that would |
| * cause the net_buf to be released by rx fiber. In this case it is |
| * application responsibility to release the buffer. |
| */ |
| return 0; |
| } |
| |
| udp_send: |
| PRINTF("In udp_send\n"); |
| if(uip_slen(buf) == 0) { |
| goto drop; |
| } |
| uip_len(buf) = uip_slen(buf) + UIP_IPUDPH_LEN; |
| ip_buf_len(buf) = uip_len(buf); |
| |
| #if NETSTACK_CONF_WITH_IPV6 |
| /* For IPv6, the IP length field does not include the IPv6 IP header |
| length. */ |
| BUF->len[0] = ((uip_len - UIP_IPH_LEN) >> 8); |
| BUF->len[1] = ((uip_len - UIP_IPH_LEN) & 0xff); |
| #else /* NETSTACK_CONF_WITH_IPV6 */ |
| BUF(buf)->len[0] = (uip_len(buf) >> 8); |
| BUF(buf)->len[1] = (uip_len(buf) & 0xff); |
| #endif /* NETSTACK_CONF_WITH_IPV6 */ |
| |
| BUF(buf)->ttl = uip_udp_conn(buf)->ttl; |
| BUF(buf)->proto = UIP_PROTO_UDP; |
| |
| UDPBUF(buf)->udplen = UIP_HTONS(uip_slen(buf) + UIP_UDPH_LEN); |
| UDPBUF(buf)->udpchksum = 0; |
| |
| BUF(buf)->srcport = uip_udp_conn(buf)->lport; |
| BUF(buf)->destport = uip_udp_conn(buf)->rport; |
| |
| uip_ipaddr_copy(&BUF(buf)->srcipaddr, &uip_hostaddr); |
| uip_ipaddr_copy(&BUF(buf)->destipaddr, &uip_udp_conn(buf)->ripaddr); |
| |
| uip_appdata(buf) = &uip_buf(buf)[UIP_LLH_LEN + UIP_IPTCPH_LEN]; |
| |
| #if UIP_UDP_CHECKSUMS |
| /* Calculate UDP checksum. */ |
| UDPBUF->udpchksum = ~(uip_udpchksum()); |
| if(UDPBUF->udpchksum == 0) { |
| UDPBUF->udpchksum = 0xffff; |
| } |
| #endif /* UIP_UDP_CHECKSUMS */ |
| |
| UIP_STAT(++uip_stat.udp.sent); |
| goto ip_send_nolen; |
| #endif /* UIP_UDP */ |
| |
| /* TCP input processing. */ |
| #if UIP_TCP |
| tcp_input: |
| UIP_STAT(++uip_stat.tcp.recv); |
| |
| /* Start of TCP input header processing code. */ |
| |
| if(uip_tcpchksum(buf) != 0xffff) { /* Compute and check the TCP |
| checksum. */ |
| UIP_STAT(++uip_stat.tcp.drop); |
| UIP_STAT(++uip_stat.tcp.chkerr); |
| UIP_LOG("tcp: bad checksum."); |
| goto drop; |
| } |
| |
| /* Make sure that the TCP port number is not zero. */ |
| if(BUF(buf)->destport == 0 || BUF(buf)->srcport == 0) { |
| UIP_LOG("tcp: zero port."); |
| goto drop; |
| } |
| |
| /* Demultiplex this segment. */ |
| /* First check any active connections. */ |
| for(uip_connr = &uip_conns[0]; uip_connr <= &uip_conns[UIP_CONNS - 1]; |
| ++uip_connr) { |
| if(uip_connr->tcpstateflags != UIP_CLOSED && |
| BUF(buf)->destport == uip_connr->lport && |
| BUF(buf)->srcport == uip_connr->rport && |
| uip_ipaddr_cmp(&BUF(buf)->srcipaddr, &uip_connr->ripaddr)) { |
| goto found; |
| } |
| } |
| |
| /* If we didn't find an active connection that expected the packet, |
| either this packet is an old duplicate, or this is a SYN packet |
| destined for a connection in LISTEN. If the SYN flag isn't set, |
| it is an old packet and we send a RST. */ |
| if((BUF(buf)->flags & TCP_CTL) != TCP_SYN) { |
| goto reset; |
| } |
| |
| tmp16 = BUF(buf)->destport; |
| /* Next, check listening connections. */ |
| for(c = 0; c < UIP_LISTENPORTS; ++c) { |
| if(tmp16 == uip_listenports[c]) { |
| goto found_listen; |
| } |
| } |
| |
| /* No matching connection found, so we send a RST packet. */ |
| UIP_STAT(++uip_stat.tcp.synrst); |
| |
| reset: |
| /* We do not send resets in response to resets. */ |
| if(BUF(buf)->flags & TCP_RST) { |
| goto drop; |
| } |
| |
| UIP_STAT(++uip_stat.tcp.rst); |
| |
| BUF(buf)->flags = TCP_RST | TCP_ACK; |
| uip_len(buf) = UIP_IPTCPH_LEN; |
| BUF(buf)->tcpoffset = 5 << 4; |
| |
| /* Flip the seqno and ackno fields in the TCP header. */ |
| c = BUF(buf)->seqno[3]; |
| BUF(buf)->seqno[3] = BUF(buf)->ackno[3]; |
| BUF(buf)->ackno[3] = c; |
| |
| c = BUF(buf)->seqno[2]; |
| BUF(buf)->seqno[2] = BUF(buf)->ackno[2]; |
| BUF(buf)->ackno[2] = c; |
| |
| c = BUF(buf)->seqno[1]; |
| BUF(buf)->seqno[1] = BUF(buf)->ackno[1]; |
| BUF(buf)->ackno[1] = c; |
| |
| c = BUF(buf)->seqno[0]; |
| BUF(buf)->seqno[0] = BUF(buf)->ackno[0]; |
| BUF(buf)->ackno[0] = c; |
| |
| /* We also have to increase the sequence number we are |
| acknowledging. If the least significant byte overflowed, we need |
| to propagate the carry to the other bytes as well. */ |
| if(++BUF(buf)->ackno[3] == 0) { |
| if(++BUF(buf)->ackno[2] == 0) { |
| if(++BUF(buf)->ackno[1] == 0) { |
| ++BUF(buf)->ackno[0]; |
| } |
| } |
| } |
| |
| /* Swap port numbers. */ |
| tmp16 = BUF(buf)->srcport; |
| BUF(buf)->srcport = BUF(buf)->destport; |
| BUF(buf)->destport = tmp16; |
| |
| /* Swap IP addresses. */ |
| uip_ipaddr_copy(&BUF(buf)->destipaddr, &BUF(buf)->srcipaddr); |
| uip_ipaddr_copy(&BUF(buf)->srcipaddr, &uip_hostaddr); |
| |
| /* And send out the RST packet! */ |
| goto tcp_send_noconn; |
| |
| /* This label will be jumped to if we matched the incoming packet |
| with a connection in LISTEN. In that case, we should create a new |
| connection and send a SYNACK in return. */ |
| found_listen: |
| PRINTF("In found listen\n"); |
| /* First we check if there are any connections avaliable. Unused |
| connections are kept in the same table as used connections, but |
| unused ones have the tcpstate set to CLOSED. Also, connections in |
| TIME_WAIT are kept track of and we'll use the oldest one if no |
| CLOSED connections are found. Thanks to Eddie C. Dost for a very |
| nice algorithm for the TIME_WAIT search. */ |
| uip_connr = 0; |
| for(c = 0; c < UIP_CONNS; ++c) { |
| if(uip_conns[c].tcpstateflags == UIP_CLOSED) { |
| uip_connr = &uip_conns[c]; |
| break; |
| } |
| if(uip_conns[c].tcpstateflags == UIP_TIME_WAIT) { |
| if(uip_connr == 0 || |
| uip_conns[c].timer > uip_connr->timer) { |
| uip_connr = &uip_conns[c]; |
| } |
| } |
| } |
| |
| if(uip_connr == 0) { |
| /* All connections are used already, we drop packet and hope that |
| the remote end will retransmit the packet at a time when we |
| have more spare connections. */ |
| UIP_STAT(++uip_stat.tcp.syndrop); |
| UIP_LOG("tcp: found no unused connections."); |
| goto drop; |
| } |
| uip_set_conn(buf) = uip_connr; |
| |
| /* Fill in the necessary fields for the new connection. */ |
| uip_connr->rto = uip_connr->timer = UIP_RTO; |
| uip_connr->sa = 0; |
| uip_connr->sv = 4; |
| uip_connr->nrtx = 0; |
| uip_connr->lport = BUF(buf)->destport; |
| uip_connr->rport = BUF(buf)->srcport; |
| uip_ipaddr_copy(&uip_connr->ripaddr, &BUF(buf)->srcipaddr); |
| uip_connr->tcpstateflags = UIP_SYN_RCVD; |
| |
| uip_connr->snd_nxt[0] = iss[0]; |
| uip_connr->snd_nxt[1] = iss[1]; |
| uip_connr->snd_nxt[2] = iss[2]; |
| uip_connr->snd_nxt[3] = iss[3]; |
| uip_connr->len = 1; |
| |
| if (flag == UIP_TCP_SEND_CONN) { |
| /* So we are trying send some data to other host */ |
| if (uip_connr->buf && uip_connr->buf != buf) { |
| uip_connr->buf = ip_buf_ref(buf); |
| } |
| } |
| |
| /* rcv_nxt should be the seqno from the incoming packet + 1. */ |
| uip_connr->rcv_nxt[3] = BUF(buf)->seqno[3]; |
| uip_connr->rcv_nxt[2] = BUF(buf)->seqno[2]; |
| uip_connr->rcv_nxt[1] = BUF(buf)->seqno[1]; |
| uip_connr->rcv_nxt[0] = BUF(buf)->seqno[0]; |
| uip_add_rcv_nxt(buf, 1); |
| |
| /* Parse the TCP MSS option, if present. */ |
| if((BUF(buf)->tcpoffset & 0xf0) > 0x50) { |
| for(c = 0; c < ((BUF(buf)->tcpoffset >> 4) - 5) << 2 ;) { |
| opt = uip_buf(buf)[UIP_TCPIP_HLEN + UIP_LLH_LEN + c]; |
| if(opt == TCP_OPT_END) { |
| /* End of options. */ |
| break; |
| } else if(opt == TCP_OPT_NOOP) { |
| ++c; |
| /* NOP option. */ |
| } else if(opt == TCP_OPT_MSS && |
| uip_buf(buf)[UIP_TCPIP_HLEN + UIP_LLH_LEN + 1 + c] == TCP_OPT_MSS_LEN) { |
| /* An MSS option with the right option length. */ |
| tmp16 = ((uint16_t)uip_buf(buf)[UIP_TCPIP_HLEN + UIP_LLH_LEN + 2 + c] << 8) | |
| (uint16_t)uip_buf(buf)[UIP_IPTCPH_LEN + UIP_LLH_LEN + 3 + c]; |
| uip_connr->initialmss = uip_connr->mss = |
| tmp16 > UIP_TCP_MSS? UIP_TCP_MSS: tmp16; |
| |
| /* And we are done processing options. */ |
| break; |
| } else { |
| /* All other options have a length field, so that we easily |
| can skip past them. */ |
| if(uip_buf(buf)[UIP_TCPIP_HLEN + UIP_LLH_LEN + 1 + c] == 0) { |
| /* If the length field is zero, the options are malformed |
| and we don't process them further. */ |
| break; |
| } |
| c += uip_buf(buf)[UIP_TCPIP_HLEN + UIP_LLH_LEN + 1 + c]; |
| } |
| } |
| } |
| |
| /* Our response will be a SYNACK. */ |
| #if UIP_ACTIVE_OPEN |
| tcp_send_synack: |
| BUF(buf)->flags = TCP_ACK; |
| |
| tcp_send_syn: |
| BUF(buf)->flags |= TCP_SYN; |
| tcp_set_retrans_timer(uip_connr); |
| #else /* UIP_ACTIVE_OPEN */ |
| tcp_send_synack: |
| BUF(buf)->flags = TCP_SYN | TCP_ACK; |
| #endif /* UIP_ACTIVE_OPEN */ |
| |
| /* We send out the TCP Maximum Segment Size option with our |
| SYNACK. */ |
| BUF(buf)->optdata[0] = TCP_OPT_MSS; |
| BUF(buf)->optdata[1] = TCP_OPT_MSS_LEN; |
| BUF(buf)->optdata[2] = (UIP_TCP_MSS) / 256; |
| BUF(buf)->optdata[3] = (UIP_TCP_MSS) & 255; |
| uip_len(buf) = UIP_IPTCPH_LEN + TCP_OPT_MSS_LEN; |
| BUF(buf)->tcpoffset = ((UIP_TCPH_LEN + TCP_OPT_MSS_LEN) / 4) << 4; |
| goto tcp_send; |
| |
| /* This label will be jumped to if we found an active connection. */ |
| found: |
| PRINTF("In found\n"); |
| uip_set_conn(buf) = uip_connr; |
| uip_flags(buf) = 0; |
| /* We do a very naive form of TCP reset processing; we just accept |
| any RST and kill our connection. We should in fact check if the |
| sequence number of this reset is within our advertised window |
| before we accept the reset. */ |
| if(BUF(buf)->flags & TCP_RST) { |
| uip_connr->tcpstateflags = UIP_CLOSED; |
| UIP_LOG("tcp: got reset, aborting connection."); |
| uip_flags(buf) = UIP_ABORT; |
| UIP_APPCALL(buf); |
| goto drop; |
| } |
| |
| if (flag != UIP_TCP_SEND_CONN) { |
| /* If flag is set to UIP_TCP_SEND_CONN, then it means that we are |
| * trying to send the actual packet coming from user. In this case |
| * do not mess with the packet length. |
| */ |
| |
| /* Calculate the length of the data, if the application has sent |
| any data to us. */ |
| c = (BUF(buf)->tcpoffset >> 4) << 2; |
| /* uip_len will contain the length of the actual TCP data. This is |
| calculated by subtracing the length of the TCP header (in |
| c) and the length of the IP header (20 bytes). */ |
| uip_len(buf) = uip_len(buf) - c - UIP_IPH_LEN; |
| } |
| |
| /* First, check if the sequence number of the incoming packet is |
| what we're expecting next. If not, we send out an ACK with the |
| correct numbers in, unless we are in the SYN_RCVD state and |
| receive a SYN, in which case we should retransmit our SYNACK |
| (which is done futher down). */ |
| if(!((((uip_connr->tcpstateflags & UIP_TS_MASK) == UIP_SYN_SENT) && |
| ((BUF(buf)->flags & TCP_CTL) == (TCP_SYN | TCP_ACK))) || |
| (((uip_connr->tcpstateflags & UIP_TS_MASK) == UIP_SYN_RCVD) && |
| ((BUF(buf)->flags & TCP_CTL) == TCP_SYN)))) { |
| if((uip_len(buf) > 0 || ((BUF(buf)->flags & (TCP_SYN | TCP_FIN)) != 0)) && |
| (BUF(buf)->seqno[0] != uip_connr->rcv_nxt[0] || |
| BUF(buf)->seqno[1] != uip_connr->rcv_nxt[1] || |
| BUF(buf)->seqno[2] != uip_connr->rcv_nxt[2] || |
| BUF(buf)->seqno[3] != uip_connr->rcv_nxt[3])) { |
| goto tcp_send_ack; |
| } |
| } |
| |
| /* Next, check if the incoming segment acknowledges any outstanding |
| data. If so, we update the sequence number, reset the length of |
| the outstanding data, calculate RTT estimations, and reset the |
| retransmission timer. */ |
| if((BUF(buf)->flags & TCP_ACK) && uip_outstanding(uip_connr)) { |
| uip_add32(uip_connr->snd_nxt, uip_connr->len); |
| |
| if(BUF(buf)->ackno[0] == uip_acc32[0] && |
| BUF(buf)->ackno[1] == uip_acc32[1] && |
| BUF(buf)->ackno[2] == uip_acc32[2] && |
| BUF(buf)->ackno[3] == uip_acc32[3]) { |
| /* Update sequence number. */ |
| uip_connr->snd_nxt[0] = uip_acc32[0]; |
| uip_connr->snd_nxt[1] = uip_acc32[1]; |
| uip_connr->snd_nxt[2] = uip_acc32[2]; |
| uip_connr->snd_nxt[3] = uip_acc32[3]; |
| |
| /* Do RTT estimation, unless we have done retransmissions. */ |
| if(uip_connr->nrtx == 0) { |
| signed char m; |
| m = uip_connr->rto - uip_connr->timer; |
| /* This is taken directly from VJs original code in his paper */ |
| m = m - (uip_connr->sa >> 3); |
| uip_connr->sa += m; |
| if(m < 0) { |
| m = -m; |
| } |
| m = m - (uip_connr->sv >> 2); |
| uip_connr->sv += m; |
| uip_connr->rto = (uip_connr->sa >> 3) + uip_connr->sv; |
| |
| } |
| /* Set the acknowledged flag. */ |
| uip_flags(buf) = UIP_ACKDATA; |
| /* Reset the retransmission timer. */ |
| uip_connr->timer = uip_connr->rto; |
| |
| /* Reset length of outstanding data. */ |
| uip_connr->len = 0; |
| } |
| |
| } |
| |
| /* Do different things depending on in what state the connection is. */ |
| switch(uip_connr->tcpstateflags & UIP_TS_MASK) { |
| /* CLOSED and LISTEN are not handled here. CLOSE_WAIT is not |
| implemented, since we force the application to close when the |
| peer sends a FIN (hence the application goes directly from |
| ESTABLISHED to LAST_ACK). */ |
| case UIP_SYN_RCVD: |
| /* In SYN_RCVD we have sent out a SYNACK in response to a SYN, and |
| we are waiting for an ACK that acknowledges the data we sent |
| out the last time. Therefore, we want to have the UIP_ACKDATA |
| flag set. If so, we enter the ESTABLISHED state. */ |
| if(uip_flags(buf) & UIP_ACKDATA) { |
| uip_connr->tcpstateflags = UIP_ESTABLISHED; |
| uip_flags(buf) = UIP_CONNECTED; |
| uip_connr->len = 0; |
| if(uip_len(buf) > 0) { |
| uip_flags(buf) |= UIP_NEWDATA; |
| uip_add_rcv_nxt(buf, uip_len(buf)); |
| } |
| uip_slen(buf) = 0; |
| UIP_APPCALL(buf); |
| goto appsend; |
| } |
| /* We need to retransmit the SYNACK */ |
| if((BUF(buf)->flags & TCP_CTL) == TCP_SYN) { |
| goto tcp_send_synack; |
| } |
| goto drop; |
| #if UIP_ACTIVE_OPEN |
| case UIP_SYN_SENT: |
| /* In SYN_SENT, we wait for a SYNACK that is sent in response to |
| our SYN. The rcv_nxt is set to sequence number in the SYNACK |
| plus one, and we send an ACK. We move into the ESTABLISHED |
| state. */ |
| if((uip_flags(buf) & UIP_ACKDATA) && |
| (BUF(buf)->flags & TCP_CTL) == (TCP_SYN | TCP_ACK)) { |
| |
| /* Parse the TCP MSS option, if present. */ |
| if((BUF(buf)->tcpoffset & 0xf0) > 0x50) { |
| for(c = 0; c < ((BUF(buf)->tcpoffset >> 4) - 5) << 2 ;) { |
| opt = uip_buf(buf)[UIP_IPTCPH_LEN + UIP_LLH_LEN + c]; |
| if(opt == TCP_OPT_END) { |
| /* End of options. */ |
| break; |
| } else if(opt == TCP_OPT_NOOP) { |
| ++c; |
| /* NOP option. */ |
| } else if(opt == TCP_OPT_MSS && |
| uip_buf(buf)[UIP_TCPIP_HLEN + UIP_LLH_LEN + 1 + c] == TCP_OPT_MSS_LEN) { |
| /* An MSS option with the right option length. */ |
| tmp16 = (uip_buf(buf)[UIP_TCPIP_HLEN + UIP_LLH_LEN + 2 + c] << 8) | |
| uip_buf(buf)[UIP_TCPIP_HLEN + UIP_LLH_LEN + 3 + c]; |
| uip_connr->initialmss = |
| uip_connr->mss = tmp16 > UIP_TCP_MSS? UIP_TCP_MSS: tmp16; |
| |
| /* And we are done processing options. */ |
| break; |
| } else { |
| /* All other options have a length field, so that we easily |
| can skip past them. */ |
| if(uip_buf(buf)[UIP_TCPIP_HLEN + UIP_LLH_LEN + 1 + c] == 0) { |
| /* If the length field is zero, the options are malformed |
| and we don't process them further. */ |
| break; |
| } |
| c += uip_buf(buf)[UIP_TCPIP_HLEN + UIP_LLH_LEN + 1 + c]; |
| } |
| } |
| } |
| uip_connr->tcpstateflags = UIP_ESTABLISHED; |
| uip_connr->rcv_nxt[0] = BUF(buf)->seqno[0]; |
| uip_connr->rcv_nxt[1] = BUF(buf)->seqno[1]; |
| uip_connr->rcv_nxt[2] = BUF(buf)->seqno[2]; |
| uip_connr->rcv_nxt[3] = BUF(buf)->seqno[3]; |
| uip_add_rcv_nxt(buf, 1); |
| uip_flags(buf) = UIP_CONNECTED | UIP_NEWDATA; |
| uip_connr->len = 0; |
| uip_len(buf) = 0; |
| uip_slen(buf) = 0; |
| ip_buf_sent_status(buf) = 0; |
| uip_set_conn(buf) = uip_connr; |
| |
| if (uip_connr->buf) { |
| /* Now that we know the original connection request, clear |
| * the buf in connr |
| */ |
| net_context_set_connection_status(ip_buf_context(uip_connr->buf), 0); |
| net_context_set_internal_connection(ip_buf_context(uip_connr->buf), |
| uip_connr); |
| tcp_cancel_retrans_timer(uip_connr); |
| |
| /* We received ACK for syn */ |
| if (uip_connr->buf) { |
| net_context_set_connection_status(ip_buf_context(uip_connr->buf), -EINPROGRESS); |
| } |
| |
| /* Now send the pending data */ |
| buf = uip_connr->buf; |
| *buf_out = buf; |
| |
| uip_flags(buf) = UIP_CONNECTED; |
| } |
| /* Right now we have received SYN-ACK so we can now start to send data. |
| * The UIP_APPCALL() will cause a call to this function by the |
| * net_context.c TCP process thread which will call |
| * handle_tcp_connection(). |
| */ |
| UIP_APPCALL(buf); |
| PRINTF("Returning now buf %p ref %p\n", buf, buf->ref); |
| return 0; |
| } |
| /* Inform the application that the connection failed */ |
| uip_flags(buf) = UIP_ABORT; |
| UIP_APPCALL(buf); |
| /* The connection is closed after we send the RST */ |
| uip_conn(buf)->tcpstateflags = UIP_CLOSED; |
| goto reset; |
| #endif /* UIP_ACTIVE_OPEN */ |
| |
| case UIP_ESTABLISHED: |
| /* In the ESTABLISHED state, we call upon the application to feed |
| data into the uip_buf. If the UIP_ACKDATA flag is set, the |
| application should put new data into the buffer, otherwise we are |
| retransmitting an old segment, and the application should put that |
| data into the buffer. |
| |
| If the incoming packet is a FIN, we should close the connection on |
| this side as well, and we send out a FIN and enter the LAST_ACK |
| state. We require that there is no outstanding data; otherwise the |
| sequence numbers will be screwed up. */ |
| |
| if(BUF(buf)->flags & TCP_FIN && !(uip_connr->tcpstateflags & UIP_STOPPED)) { |
| if(uip_outstanding(uip_connr)) { |
| goto drop; |
| } |
| uip_add_rcv_nxt(buf, 1 + uip_len(buf)); |
| uip_flags(buf) |= UIP_CLOSE; |
| if(uip_len(buf) > 0) { |
| uip_flags(buf) |= UIP_NEWDATA; |
| } |
| UIP_APPCALL(buf); |
| uip_connr->len = 1; |
| uip_connr->tcpstateflags = UIP_LAST_ACK; |
| uip_connr->nrtx = 0; |
| tcp_send_finack: |
| BUF(buf)->flags = TCP_FIN | TCP_ACK; |
| goto tcp_send_nodata; |
| } |
| |
| /* Check the URG flag. If this is set, the segment carries urgent |
| data that we must pass to the application. */ |
| if((BUF(buf)->flags & TCP_URG) != 0) { |
| #if UIP_URGDATA > 0 |
| uip_urglen = (BUF->urgp[0] << 8) | BUF->urgp[1]; |
| if(uip_urglen > uip_len) { |
| /* There is more urgent data in the next segment to come. */ |
| uip_urglen = uip_len; |
| } |
| uip_add_rcv_nxt(uip_urglen); |
| uip_len -= uip_urglen; |
| uip_urgdata = uip_appdata; |
| uip_appdata += uip_urglen; |
| } else { |
| uip_urglen = 0; |
| #else /* UIP_URGDATA > 0 */ |
| uip_appdata(buf) = ((char *)uip_appdata(buf)) + ((BUF(buf)->urgp[0] << 8) | BUF(buf)->urgp[1]); |
| uip_len(buf) -= (BUF(buf)->urgp[0] << 8) | BUF(buf)->urgp[1]; |
| #endif /* UIP_URGDATA > 0 */ |
| } |
| |
| /* If uip_len > 0 we have TCP data in the packet, and we flag this |
| by setting the UIP_NEWDATA flag and update the sequence number |
| we acknowledge. If the application has stopped the dataflow |
| using uip_stop(), we must not accept any data packets from the |
| remote host. */ |
| if(uip_len(buf) > 0 && !(uip_connr->tcpstateflags & UIP_STOPPED)) { |
| uip_flags(buf) |= UIP_NEWDATA; |
| uip_add_rcv_nxt(buf, uip_len(buf)); |
| } |
| |
| /* Check if the available buffer space advertised by the other end |
| is smaller than the initial MSS for this connection. If so, we |
| set the current MSS to the window size to ensure that the |
| application does not send more data than the other end can |
| handle. |
| |
| If the remote host advertises a zero window, we set the MSS to |
| the initial MSS so that the application will send an entire MSS |
| of data. This data will not be acknowledged by the receiver, |
| and the application will retransmit it. This is called the |
| "persistent timer" and uses the retransmission mechanim. |
| */ |
| tmp16 = ((uint16_t)BUF(buf)->wnd[0] << 8) + (uint16_t)BUF(buf)->wnd[1]; |
| if(tmp16 > uip_connr->initialmss || |
| tmp16 == 0) { |
| tmp16 = uip_connr->initialmss; |
| } |
| uip_connr->mss = tmp16; |
| |
| /* If this packet constitutes an ACK for outstanding data (flagged |
| by the UIP_ACKDATA flag, we should call the application since it |
| might want to send more data. If the incoming packet had data |
| from the peer (as flagged by the UIP_NEWDATA flag), the |
| application must also be notified. |
| |
| When the application is called, the global variable uip_len |
| contains the length of the incoming data. The application can |
| access the incoming data through the global pointer |
| uip_appdata, which usually points UIP_IPTCPH_LEN + UIP_LLH_LEN |
| bytes into the uip_buf array. |
| |
| If the application wishes to send any data, this data should be |
| put into the uip_appdata and the length of the data should be |
| put into uip_len. If the application don't have any data to |
| send, uip_len must be set to 0. */ |
| if(uip_flags(buf) & (UIP_NEWDATA | UIP_ACKDATA)) { |
| if(flag != UIP_TCP_SEND_CONN) { |
| /* Do not reset the slen because we are being called |
| * directly by the application. |
| */ |
| uip_slen(buf) = 0; |
| } |
| |
| if (uip_connr->buf) { |
| net_context_tcp_set_pending(ip_buf_context(uip_connr->buf), NULL); |
| net_context_set_internal_connection(ip_buf_context(uip_connr->buf), |
| uip_connr); |
| |
| /* At this point we have received ACK to data in uip_connr->buf */ |
| |
| /* This is not an error but tells net_core.c:net_send() that |
| * user should be able to send now more data. |
| */ |
| net_context_set_connection_status(ip_buf_context(uip_connr->buf), |
| EISCONN); |
| |
| /* Eventually the uip_connr->buf will be freed |
| * by net_core.c:net_send() |
| */ |
| |
| tcp_cancel_retrans_timer(uip_connr); |
| |
| } else { |
| /* We have no pending data so this will cause ACK to be sent to |
| * peer in few lines below. |
| */ |
| uip_flags(buf) |= UIP_NEWDATA; |
| } |
| |
| UIP_APPCALL(buf); |
| |
| appsend: |
| |
| if(uip_flags(buf) & UIP_ABORT) { |
| uip_slen(buf) = 0; |
| uip_connr->tcpstateflags = UIP_CLOSED; |
| BUF(buf)->flags = TCP_RST | TCP_ACK; |
| goto tcp_send_nodata; |
| } |
| |
| if(uip_flags(buf) & UIP_CLOSE) { |
| uip_slen(buf) = 0; |
| uip_connr->len = 1; |
| uip_connr->tcpstateflags = UIP_FIN_WAIT_1; |
| uip_connr->nrtx = 0; |
| BUF(buf)->flags = TCP_FIN | TCP_ACK; |
| goto tcp_send_nodata; |
| } |
| |
| /* If uip_slen > 0, the application has data to be sent. */ |
| if(uip_slen(buf) > 0) { |
| |
| /* If the connection has acknowledged data, the contents of |
| the ->len variable should be discarded. */ |
| if((uip_flags(buf) & UIP_ACKDATA) != 0) { |
| uip_connr->len = 0; |
| } |
| |
| /* If the ->len variable is non-zero the connection has |
| already data in transit and cannot send anymore right |
| now. */ |
| if(uip_connr->len == 0) { |
| |
| /* The application cannot send more than what is allowed by |
| the mss (the minumum of the MSS and the available |
| window). */ |
| if(uip_slen(buf) > uip_connr->mss) { |
| uip_slen(buf) = uip_connr->mss; |
| } |
| |
| /* Remember how much data we send out now so that we know |
| when everything has been acknowledged. */ |
| uip_connr->len = uip_slen(buf); |
| |
| PRINTF("Setting connection %p to pending length %d\n", |
| uip_connr, uip_connr->len); |
| |
| if (uip_connr->buf) { |
| if (uip_connr->buf != buf) { |
| PRINTF("Data packet %p already pending....\n", |
| uip_connr->buf); |
| } |
| } else { |
| uip_connr->buf = ip_buf_ref(buf); |
| } |
| |
| } else { |
| |
| /* If the application already had unacknowledged data, we |
| make sure that the application does not send (i.e., |
| retransmit) out more than it previously sent out. */ |
| uip_slen(buf) = uip_connr->len; |
| } |
| } |
| uip_connr->nrtx = 0; |
| apprexmit: |
| uip_appdata(buf) = uip_sappdata(buf); |
| |
| /* If the application has data to be sent, or if the incoming |
| packet had new data in it, we must send out a packet. */ |
| if(uip_slen(buf) > 0 && uip_connr->len > 0) { |
| /* Add the length of the IP and TCP headers. */ |
| uip_len(buf) = uip_connr->len + UIP_TCPIP_HLEN; |
| /* We always set the ACK flag in response packets. */ |
| BUF(buf)->flags = TCP_ACK | TCP_PSH; |
| /* Send the packet. */ |
| goto tcp_send_noopts; |
| } |
| /* If there is no data to send, just send out a pure ACK if |
| there is newdata. */ |
| if(uip_flags(buf) & UIP_NEWDATA) { |
| uip_len(buf) = UIP_TCPIP_HLEN; |
| BUF(buf)->flags = TCP_ACK; |
| goto tcp_send_noopts; |
| } |
| } |
| goto drop; |
| case UIP_LAST_ACK: |
| /* We can close this connection if the peer has acknowledged our |
| FIN. This is indicated by the UIP_ACKDATA flag. */ |
| if(uip_flags(buf) & UIP_ACKDATA) { |
| uip_connr->tcpstateflags = UIP_CLOSED; |
| uip_flags(buf) = UIP_CLOSE; |
| UIP_APPCALL(buf); |
| } |
| break; |
| |
| case UIP_FIN_WAIT_1: |
| /* The application has closed the connection, but the remote host |
| hasn't closed its end yet. Thus we do nothing but wait for a |
| FIN from the other side. */ |
| if(uip_len(buf) > 0) { |
| uip_add_rcv_nxt(buf, uip_len(buf)); |
| } |
| if(BUF(buf)->flags & TCP_FIN) { |
| if(uip_flags(buf) & UIP_ACKDATA) { |
| uip_connr->tcpstateflags = UIP_TIME_WAIT; |
| uip_connr->timer = 0; |
| uip_connr->len = 0; |
| } else { |
| uip_connr->tcpstateflags = UIP_CLOSING; |
| } |
| uip_add_rcv_nxt(buf, 1); |
| uip_flags(buf) = UIP_CLOSE; |
| UIP_APPCALL(buf); |
| goto tcp_send_ack; |
| } else if(uip_flags(buf) & UIP_ACKDATA) { |
| uip_connr->tcpstateflags = UIP_FIN_WAIT_2; |
| uip_connr->len = 0; |
| goto drop; |
| } |
| if(uip_len(buf) > 0) { |
| goto tcp_send_ack; |
| } |
| goto drop; |
| |
| case UIP_FIN_WAIT_2: |
| if(uip_len(buf) > 0) { |
| uip_add_rcv_nxt(buf, uip_len(buf)); |
| } |
| if(BUF(buf)->flags & TCP_FIN) { |
| uip_connr->tcpstateflags = UIP_TIME_WAIT; |
| uip_connr->timer = 0; |
| uip_add_rcv_nxt(buf, 1); |
| uip_flags(buf) = UIP_CLOSE; |
| UIP_APPCALL(buf); |
| goto tcp_send_ack; |
| } |
| if(uip_len(buf) > 0) { |
| goto tcp_send_ack; |
| } |
| goto drop; |
| |
| case UIP_TIME_WAIT: |
| goto tcp_send_ack; |
| |
| case UIP_CLOSING: |
| if(uip_flags(buf) & UIP_ACKDATA) { |
| uip_connr->tcpstateflags = UIP_TIME_WAIT; |
| uip_connr->timer = 0; |
| } |
| } |
| goto drop; |
| |
| /* We jump here when we are ready to send the packet, and just want |
| to set the appropriate TCP sequence numbers in the TCP header. */ |
| tcp_send_ack: |
| PRINTF("In tcp_send_ack\n"); |
| BUF(buf)->flags = TCP_ACK; |
| |
| tcp_send_nodata: |
| if (flag != UIP_TCP_SEND_CONN) { |
| PRINTF("In tcp_send_nodata\n"); |
| uip_len(buf) = UIP_IPTCPH_LEN; |
| buf->len = UIP_IPTCPH_LEN; |
| } |
| |
| tcp_send_noopts: |
| BUF(buf)->tcpoffset = (UIP_TCPH_LEN / 4) << 4; |
| |
| /* We're done with the input processing. We are now ready to send a |
| reply. Our job is to fill in all the fields of the TCP and IP |
| headers before calculating the checksum and finally send the |
| packet. */ |
| tcp_send: |
| PRINTF("In tcp_send\n"); |
| |
| BUF(buf)->ackno[0] = uip_connr->rcv_nxt[0]; |
| BUF(buf)->ackno[1] = uip_connr->rcv_nxt[1]; |
| BUF(buf)->ackno[2] = uip_connr->rcv_nxt[2]; |
| BUF(buf)->ackno[3] = uip_connr->rcv_nxt[3]; |
| |
| BUF(buf)->seqno[0] = uip_connr->snd_nxt[0]; |
| BUF(buf)->seqno[1] = uip_connr->snd_nxt[1]; |
| BUF(buf)->seqno[2] = uip_connr->snd_nxt[2]; |
| BUF(buf)->seqno[3] = uip_connr->snd_nxt[3]; |
| |
| BUF(buf)->srcport = uip_connr->lport; |
| BUF(buf)->destport = uip_connr->rport; |
| |
| uip_ipaddr_copy(&BUF(buf)->srcipaddr, &uip_hostaddr); |
| uip_ipaddr_copy(&BUF(buf)->destipaddr, &uip_connr->ripaddr); |
| PRINTF("Sending TCP packet to "); |
| PRINT6ADDR(&BUF(buf)->destipaddr); |
| PRINTF(" from "); |
| PRINT6ADDR(&BUF(buf)->srcipaddr); |
| PRINTF("\n"); |
| |
| if(uip_connr->tcpstateflags & UIP_STOPPED) { |
| /* If the connection has issued uip_stop(), we advertise a zero |
| window so that the remote host will stop sending data. */ |
| BUF(buf)->wnd[0] = BUF(buf)->wnd[1] = 0; |
| } else { |
| BUF(buf)->wnd[0] = ((UIP_RECEIVE_WINDOW) >> 8); |
| BUF(buf)->wnd[1] = ((UIP_RECEIVE_WINDOW) & 0xff); |
| } |
| |
| tcp_send_noconn: |
| BUF(buf)->proto = UIP_PROTO_TCP; |
| |
| BUF(buf)->ttl = UIP_TTL; |
| #if NETSTACK_CONF_WITH_IPV6 |
| /* For IPv6, the IP length field does not include the IPv6 IP header |
| length. */ |
| BUF->len[0] = ((uip_len - UIP_IPH_LEN) >> 8); |
| BUF->len[1] = ((uip_len - UIP_IPH_LEN) & 0xff); |
| #else /* NETSTACK_CONF_WITH_IPV6 */ |
| BUF(buf)->len[0] = (uip_len(buf) >> 8); |
| BUF(buf)->len[1] = (uip_len(buf) & 0xff); |
| #endif /* NETSTACK_CONF_WITH_IPV6 */ |
| |
| BUF(buf)->urgp[0] = BUF(buf)->urgp[1] = 0; |
| |
| /* Calculate TCP checksum. */ |
| BUF(buf)->tcpchksum = 0; |
| BUF(buf)->tcpchksum = ~(uip_tcpchksum(buf)); |
| #endif |
| |
| ip_send_nolen: |
| #if NETSTACK_CONF_WITH_IPV6 |
| BUF->vtc = 0x60; |
| BUF->tcflow = 0x00; |
| BUF->flow = 0x00; |
| #else /* NETSTACK_CONF_WITH_IPV6 */ |
| BUF(buf)->vhl = 0x45; |
| BUF(buf)->tos = 0; |
| BUF(buf)->ipoffset[0] = BUF(buf)->ipoffset[1] = 0; |
| ++ipid; |
| BUF(buf)->ipid[0] = ipid >> 8; |
| BUF(buf)->ipid[1] = ipid & 0xff; |
| /* Calculate IP checksum. */ |
| BUF(buf)->ipchksum = 0; |
| BUF(buf)->ipchksum = ~(uip_ipchksum(buf)); |
| PRINTF("uip ip_send_nolen: chkecum 0x%04x\n", uip_ipchksum(buf)); |
| #endif /* NETSTACK_CONF_WITH_IPV6 */ |
| UIP_STAT(++uip_stat.tcp.sent); |
| #if NETSTACK_CONF_WITH_IPV6 |
| send: |
| #endif /* NETSTACK_CONF_WITH_IPV6 */ |
| PRINTF("Sending packet with length %d (%d)\n", uip_len(buf), |
| (BUF(buf)->len[0] << 8) | BUF(buf)->len[1]); |
| |
| UIP_STAT(++uip_stat.ip.sent); |
| /* Return and let the caller do the actual transmission. */ |
| uip_flags(buf) = 0; |
| return 1; |
| |
| drop: |
| uip_len(buf) = 0; |
| uip_flags(buf) = 0; |
| |
| #if UIP_TCP |
| /* Clear any pending packet */ |
| if (uip_connr && uip_connr->buf) { |
| tcp_cancel_retrans_timer(uip_connr); |
| switch (uip_connr->tcpstateflags & UIP_TS_MASK) { |
| case UIP_FIN_WAIT_1: |
| case UIP_FIN_WAIT_2: |
| case UIP_CLOSING: |
| case UIP_TIME_WAIT: |
| ip_buf_unref(uip_connr->buf); |
| uip_connr->buf = NULL; |
| } |
| } |
| #endif |
| |
| return 0; |
| } |
| /*---------------------------------------------------------------------------*/ |
| uint16_t |
| uip_htons(uint16_t val) |
| { |
| return UIP_HTONS(val); |
| } |
| |
| uint32_t |
| uip_htonl(uint32_t val) |
| { |
| return UIP_HTONL(val); |
| } |
| /*---------------------------------------------------------------------------*/ |
| #if UIP_TCP |
| void |
| uip_send(struct net_buf *buf, const void *data, int len) |
| { |
| int copylen; |
| #define MIN(a,b) ((a) < (b)? (a): (b)) |
| |
| uip_sappdata(buf) = ip_buf_appdata(buf); |
| |
| if(uip_sappdata(buf) != NULL) { |
| copylen = MIN(len, UIP_BUFSIZE - UIP_LLH_LEN - UIP_TCPIP_HLEN - |
| (int)((char *)uip_sappdata(buf) - |
| (char *)&uip_buf(buf)[UIP_LLH_LEN + UIP_TCPIP_HLEN])); |
| } else { |
| copylen = MIN(len, UIP_BUFSIZE - UIP_LLH_LEN - UIP_TCPIP_HLEN); |
| } |
| if(copylen > 0) { |
| uip_slen(buf) = copylen; |
| if(data != uip_sappdata(buf)) { |
| if(uip_sappdata(buf) == NULL) { |
| memmove((char *)&uip_buf(buf)[UIP_LLH_LEN + UIP_TCPIP_HLEN], |
| (data), uip_slen(buf)); |
| } else { |
| memmove(uip_sappdata(buf), (data), uip_slen(buf)); |
| } |
| } |
| if (uip_process(&buf, UIP_TCP_SEND_CONN)) { |
| int ret = tcpip_output(buf, NULL); |
| if (!ret) { |
| PRINTF("Packet %p sending failed.\n", buf); |
| ip_buf_sent_status(buf) = -EAGAIN; |
| } |
| } |
| } |
| } |
| #endif |
| |
| #if UIP_UDP |
| void |
| uip_send_udp(struct net_buf *buf, const void *data, int len) |
| { |
| uip_slen(buf) = len; |
| |
| if (uip_process(&buf, UIP_UDP_SEND_CONN)) { |
| int ret = tcpip_output(buf, NULL); |
| if (!ret) { |
| PRINTF("Packet %p sending failed.\n", buf); |
| ip_buf_unref(buf); |
| } |
| } |
| } |
| #endif |
| /*---------------------------------------------------------------------------*/ |
| /** @}*/ |