| /* |
| * 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. |
| * |
| * |
| */ |
| |
| /** |
| * \addtogroup uip6 |
| * @{ |
| */ |
| |
| /** |
| * \file |
| * The uIP TCP/IPv6 stack code. |
| * |
| * \author Adam Dunkels <adam@sics.se> |
| * \author Julien Abeille <jabeille@cisco.com> (IPv6 related code) |
| * \author Mathilde Durvy <mdurvy@cisco.com> (IPv6 related code) |
| */ |
| |
| /* |
| * 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 optimizer 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 wishes 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 <net/ip_buf.h> |
| #include <net/net_ip.h> |
| #include <errno.h> |
| |
| #include "contiki/ip/uip.h" |
| #include "contiki/ip/uipopt.h" |
| #include "contiki/ipv6/uip-icmp6.h" |
| #include "contiki/ipv6/uip-nd6.h" |
| #include "contiki/ipv6/uip-ds6.h" |
| #include "contiki/ipv6/multicast/uip-mcast6.h" |
| |
| #include <string.h> |
| |
| /*---------------------------------------------------------------------------*/ |
| /* For Debug, logging, statistics */ |
| /*---------------------------------------------------------------------------*/ |
| |
| #ifdef CONFIG_NETWORK_IP_STACK_DEBUG_IPV6 |
| #define DEBUG 1 |
| #endif |
| #include "contiki/ip/uip-debug.h" |
| |
| #if UIP_CONF_IPV6_RPL |
| #include "rpl/rpl.h" |
| #endif /* UIP_CONF_IPV6_RPL */ |
| |
| #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_STATISTICS == 1 |
| struct uip_stats uip_stat; |
| #endif /* UIP_STATISTICS == 1 */ |
| |
| |
| /*---------------------------------------------------------------------------*/ |
| /** |
| * \name Layer 2 variables |
| * @{ |
| */ |
| /*---------------------------------------------------------------------------*/ |
| /** Host L2 address */ |
| #if UIP_CONF_LL_802154 |
| uip_lladdr_t uip_lladdr; |
| #else /*UIP_CONF_LL_802154*/ |
| uip_lladdr_t uip_lladdr = {{0x00,0x06,0x98,0x00,0x02,0x32}}; |
| #endif /*UIP_CONF_LL_802154*/ |
| /** @} */ |
| |
| /*---------------------------------------------------------------------------*/ |
| /** |
| * \name Layer 3 variables |
| * @{ |
| */ |
| /*---------------------------------------------------------------------------*/ |
| /** |
| * \brief Type of the next header in IPv6 header or extension headers |
| * |
| * Can be the next header field in the IPv6 header or in an extension header. |
| * When doing fragment reassembly, we must change the value of the next header |
| * field in the header before the fragmentation header, hence we need a pointer |
| * to this field. |
| */ |
| #if 0 |
| /* Global variables cannot be used, these are moved to net_buf */ |
| uint8_t *uip_next_hdr; |
| /** \brief bitmap we use to record which IPv6 headers we have already seen */ |
| uint8_t uip_ext_bitmap = 0; |
| /** |
| * \brief length of the extension headers read. updated each time we process |
| * a header |
| */ |
| uint8_t uip_ext_len = 0; |
| /** \brief length of the header options read */ |
| uint8_t uip_ext_opt_offset = 0; |
| #endif |
| /** @} */ |
| |
| /*---------------------------------------------------------------------------*/ |
| /* Buffers */ |
| /*---------------------------------------------------------------------------*/ |
| /** |
| * \name Buffer defines |
| * @{ |
| */ |
| #define FBUF(buf) ((struct uip_tcpip_hdr *)&uip_reassbuf(buf)[0]) |
| #define UIP_IP_BUF(buf) ((struct uip_ip_hdr *)&uip_buf(buf)[UIP_LLH_LEN]) |
| #define UIP_ICMP_BUF(buf) ((struct uip_icmp_hdr *)&uip_buf(buf)[uip_l2_l3_hdr_len(buf)]) |
| #define UIP_UDP_BUF(buf) ((struct uip_udp_hdr *)&uip_buf(buf)[UIP_LLH_LEN + UIP_IPH_LEN]) |
| #define UIP_TCP_BUF(buf) ((struct uip_tcp_hdr *)&uip_buf(buf)[UIP_LLH_LEN + UIP_IPH_LEN]) |
| #define UIP_EXT_BUF(buf) ((struct uip_ext_hdr *)&uip_buf(buf)[uip_l2_l3_hdr_len(buf)]) |
| #define UIP_ROUTING_BUF(buf) ((struct uip_routing_hdr *)&uip_buf(buf)[uip_l2_l3_hdr_len(buf)]) |
| #define UIP_FRAG_BUF(buf) ((struct uip_frag_hdr *)&uip_buf(buf)[uip_l2_l3_hdr_len(buf)]) |
| #define UIP_HBHO_BUF(buf) ((struct uip_hbho_hdr *)&uip_buf(buf)[uip_l2_l3_hdr_len(buf)]) |
| #define UIP_DESTO_BUF(buf) ((struct uip_desto_hdr *)&uip_buf(buf)[uip_l2_l3_hdr_len(buf)]) |
| #define UIP_EXT_HDR_OPT_BUF(buf) ((struct uip_ext_hdr_opt *)&uip_buf(buf)[uip_l2_l3_hdr_len(buf) + uip_ext_opt_offset(buf)]) |
| #define UIP_EXT_HDR_OPT_PADN_BUF(buf) ((struct uip_ext_hdr_opt_padn *)&uip_buf(buf)[uip_l2_l3_hdr_len(buf) + uip_ext_opt_offset(buf)]) |
| #if UIP_CONF_IPV6_RPL |
| #define UIP_EXT_HDR_OPT_RPL_BUF(buf) ((struct uip_ext_hdr_opt_rpl *)&uip_buf(buf)[uip_l2_l3_hdr_len(buf) + uip_ext_opt_offset(buf)]) |
| #endif /* UIP_CONF_IPV6_RPL */ |
| #define UIP_ICMP6_ERROR_BUF(buf) ((struct uip_icmp6_error *)&uip_buf(buf)[uip_l2_l3_icmp_hdr_len(buf)]) |
| /** @} */ |
| /** |
| * \name Buffer variables |
| * @{ |
| */ |
| /** Packet buffer for incoming and outgoing packets */ |
| #if 0 |
| /* Global variables cannot be used, these are now in net_buf */ |
| #ifndef UIP_CONF_EXTERNAL_BUFFER |
| uip_buf_t uip_aligned_buf; |
| #endif /* UIP_CONF_EXTERNAL_BUFFER */ |
| |
| /* The uip_appdata pointer points to application data. */ |
| void *uip_appdata; |
| /* The uip_appdata pointer points to the application data which is to be sent*/ |
| void *uip_sappdata; |
| #endif |
| |
| #if UIP_URGDATA > 0 |
| /* The uip_urgdata pointer points to urgent data (out-of-band data), if present */ |
| void *uip_urgdata; |
| uint16_t uip_urglen, uip_surglen; |
| #endif /* UIP_URGDATA > 0 */ |
| |
| /* The uip_len is either 8 or 16 bits, depending on the maximum packet size.*/ |
| /* uint16_t uip_len, uip_slen; No longer used as len is part of net_buf */ |
| /** @} */ |
| |
| /*---------------------------------------------------------------------------*/ |
| /** |
| * \name General variables |
| * @{ |
| */ |
| /*---------------------------------------------------------------------------*/ |
| |
| #if 0 |
| /* Global variables cannot be used, these are now in net_buf */ |
| |
| /* The uip_flags variable is used for communication between the TCP/IP stack |
| and the application program. */ |
| uint8_t uip_flags; |
| |
| /* uip_conn always points to the current connection (set to NULL for UDP). */ |
| struct uip_conn *uip_conn; |
| #endif |
| |
| #if UIP_ACTIVE_OPEN || UIP_UDP |
| /* Keeps track of the last port used for a new connection. */ |
| static uint16_t lastport; |
| #endif /* UIP_ACTIVE_OPEN || UIP_UDP */ |
| /** @} */ |
| |
| /*---------------------------------------------------------------------------*/ |
| /* TCP */ |
| /*---------------------------------------------------------------------------*/ |
| /** |
| * \name TCP defines |
| *@{ |
| */ |
| /* 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. */ |
| /** @} */ |
| /** |
| * \name TCP variables |
| *@{ |
| */ |
| #if UIP_TCP |
| /* The uip_conns array holds all TCP connections. */ |
| struct uip_conn uip_conns[UIP_CONNS]; |
| |
| /* The uip_listenports list all currently listning ports. */ |
| uint16_t uip_listenports[UIP_LISTENPORTS]; |
| |
| /* The iss variable is used for the TCP initial sequence number. */ |
| static uint8_t iss[4]; |
| |
| /* Temporary variables. */ |
| uint8_t uip_acc32[4]; |
| static uint8_t opt; |
| static uint16_t tmp16; |
| #endif /* UIP_TCP */ |
| /** @} */ |
| |
| /*---------------------------------------------------------------------------*/ |
| /** |
| * \name UDP variables |
| * @{ |
| */ |
| /*---------------------------------------------------------------------------*/ |
| #if UIP_UDP |
| #if 0 |
| /* Moved to net_buf */ |
| struct uip_udp_conn *uip_udp_conn; |
| #endif |
| struct uip_udp_conn uip_udp_conns[UIP_UDP_CONNS]; |
| #endif /* UIP_UDP */ |
| /** @} */ |
| |
| /*---------------------------------------------------------------------------*/ |
| /** |
| * \name ICMPv6 variables |
| * @{ |
| */ |
| /*---------------------------------------------------------------------------*/ |
| #if UIP_CONF_ICMP6 |
| /** single possible icmpv6 "connection" */ |
| struct uip_icmp6_conn uip_icmp6_conns; |
| #endif /*UIP_CONF_ICMP6*/ |
| /** @} */ |
| |
| /*---------------------------------------------------------------------------*/ |
| /* Functions */ |
| /*---------------------------------------------------------------------------*/ |
| #if (!UIP_ARCH_ADD32 && UIP_TCP) |
| 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 && UIP_TCP */ |
| |
| #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); |
| 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) |
| { |
| /* gcc 4.4.0 - 4.6.1 (maybe 4.3...) with -Os on 8 bit CPUS incorrectly compiles: |
| * int bar (int); |
| * int foo (unsigned char a, unsigned char b) { |
| * int len = (a << 8) + b; //len becomes 0xff00&<random>+b |
| * return len + bar (len); |
| * } |
| * upper_layer_len triggers this bug unless it is declared volatile. |
| * See https://sourceforge.net/apps/mantisbt/contiki/view.php?id=3 |
| */ |
| volatile uint16_t upper_layer_len; |
| uint16_t sum; |
| |
| upper_layer_len = (((uint16_t)(UIP_IP_BUF(buf)->len[0]) << 8) + UIP_IP_BUF(buf)->len[1] - uip_ext_len(buf)); |
| |
| PRINTF("Upper layer checksum len: %d from: %d\n", upper_layer_len, |
| UIP_IPH_LEN + UIP_LLH_LEN + uip_ext_len(buf)); |
| |
| /* 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 *)&UIP_IP_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 + uip_ext_len(buf)], |
| upper_layer_len); |
| |
| return (sum == 0) ? 0xffff : uip_htons(sum); |
| } |
| /*---------------------------------------------------------------------------*/ |
| uint16_t |
| uip_icmp6chksum(struct net_buf *buf) |
| { |
| return upper_layer_chksum(buf, UIP_PROTO_ICMP6); |
| |
| } |
| /*---------------------------------------------------------------------------*/ |
| #if UIP_TCP |
| uint16_t |
| uip_tcpchksum(struct net_buf *buf) |
| { |
| return upper_layer_chksum(buf, UIP_PROTO_TCP); |
| } |
| #endif /* UIP_TCP */ |
| /*---------------------------------------------------------------------------*/ |
| #if UIP_UDP && UIP_UDP_CHECKSUMS |
| uint16_t |
| uip_udpchksum(struct net_buf *buf) |
| { |
| return upper_layer_chksum(buf, UIP_PROTO_UDP); |
| } |
| #endif /* UIP_UDP && UIP_UDP_CHECKSUMS */ |
| #endif /* UIP_ARCH_CHKSUM */ |
| /*---------------------------------------------------------------------------*/ |
| void |
| uip_init(void) |
| { |
| #if UIP_TCP |
| uint8_t c; |
| #endif |
| |
| uip_ds6_init(); |
| uip_icmp6_init(); |
| uip_nd6_init(); |
| |
| #if UIP_TCP |
| for(c = 0; c < UIP_LISTENPORTS; ++c) { |
| uip_listenports[c] = 0; |
| } |
| for(c = 0; c < UIP_CONNS; ++c) { |
| uip_conns[c].tcpstateflags = UIP_CLOSED; |
| uip_conns[c].len = 0; |
| } |
| |
| { |
| /* Randomise initial seq number */ |
| uint32_t c = clock_get_cycle(); |
| iss[0] = c & 0xff; |
| iss[1] = (c & 0xff00) >> 8; |
| iss[2] = (c & 0xff0000) >> 16; |
| iss[3] = (c & 0xff000000) >> 24; |
| } |
| #endif /* UIP_TCP */ |
| |
| #if UIP_ACTIVE_OPEN || UIP_UDP |
| lastport = 1024; |
| #endif /* UIP_ACTIVE_OPEN || UIP_UDP */ |
| |
| #if UIP_UDP |
| memset(&uip_udp_conns, 0, sizeof(uip_udp_conns)); |
| #endif /* UIP_UDP */ |
| |
| #if UIP_CONF_IPV6_MULTICAST |
| UIP_MCAST6.init(); |
| #endif |
| } |
| /*---------------------------------------------------------------------------*/ |
| #if UIP_TCP && UIP_ACTIVE_OPEN |
| struct uip_conn * |
| uip_connect(const uip_ipaddr_t *ripaddr, uint16_t rport) |
| { |
| register struct uip_conn *conn, *cconn; |
| uint8_t c; |
| |
| /* 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->rcv_nxt[0] = 0; |
| conn->rcv_nxt[1] = 0; |
| conn->rcv_nxt[2] = 0; |
| conn->rcv_nxt[3] = 0; |
| |
| 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_TCP && UIP_ACTIVE_OPEN */ |
| /*---------------------------------------------------------------------------*/ |
| void |
| remove_ext_hdr(struct net_buf *buf) |
| { |
| /* Remove ext header before TCP/UDP processing. */ |
| if(uip_ext_len(buf) > 0) { |
| PRINTF("Cutting ext-header before processing (extlen: %d, uiplen: %d)\n", |
| uip_ext_len(buf), uip_len(buf)); |
| if(uip_len(buf) < UIP_IPH_LEN + uip_ext_len(buf)) { |
| PRINTF("ERROR: uip_len too short compared to ext len\n"); |
| uip_ext_len(buf) = 0; |
| uip_len(buf) = 0; |
| return; |
| } |
| memmove(((uint8_t *)UIP_TCP_BUF(buf)), |
| (uint8_t *)UIP_TCP_BUF(buf) + uip_ext_len(buf), |
| uip_len(buf) - UIP_IPH_LEN - uip_ext_len(buf)); |
| |
| uip_len(buf) -= uip_ext_len(buf); |
| ip_buf_len(buf) = uip_len(buf); |
| |
| /* Update the IP length. */ |
| UIP_IP_BUF(buf)->len[0] = (uip_len(buf) - UIP_IPH_LEN) >> 8; |
| UIP_IP_BUF(buf)->len[1] = (uip_len(buf) - UIP_IPH_LEN) & 0xff; |
| uip_ext_len(buf) = 0; |
| } |
| } |
| /*---------------------------------------------------------------------------*/ |
| #if UIP_UDP |
| struct uip_udp_conn * |
| uip_udp_new(const uip_ipaddr_t *ripaddr, uint16_t rport) |
| { |
| register struct uip_udp_conn *conn; |
| uint8_t c; |
| |
| /* 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_ds6_if.cur_hop_limit; |
| |
| return conn; |
| } |
| #endif /* UIP_UDP */ |
| /*---------------------------------------------------------------------------*/ |
| #if UIP_TCP |
| void |
| uip_unlisten(uint16_t port) |
| { |
| uint8_t c; |
| for(c = 0; c < UIP_LISTENPORTS; ++c) { |
| if(uip_listenports[c] == port) { |
| uip_listenports[c] = 0; |
| return; |
| } |
| } |
| } |
| /*---------------------------------------------------------------------------*/ |
| void |
| uip_listen(uint16_t port) |
| { |
| uint8_t c; |
| for(c = 0; c < UIP_LISTENPORTS; ++c) { |
| if(uip_listenports[c] == 0) { |
| uip_listenports[c] = port; |
| return; |
| } |
| } |
| } |
| #endif |
| /*---------------------------------------------------------------------------*/ |
| |
| #if UIP_CONF_IPV6_REASSEMBLY |
| #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)]; |
| /*the first byte of an IP fragment is aligned on an 8-byte boundary */ |
| |
| 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 |
| #define UIP_REASS_FLAG_FIRSTFRAG 0x02 |
| #define UIP_REASS_FLAG_ERROR_MSG 0x04 |
| |
| |
| /* |
| * See RFC 2460 for a description of fragmentation in IPv6 |
| * A typical Ipv6 fragment |
| * +------------------+--------+--------------+ |
| * | Unfragmentable |Fragment| first | |
| * | Part | Header | fragment | |
| * +------------------+--------+--------------+ |
| */ |
| |
| |
| struct etimer uip_reass_timer; /* timer for reassembly */ |
| uint8_t uip_reass_on; /* equal to 1 if we are currently reassembling a packet */ |
| |
| static uint32_t uip_id; /* For every packet that is to be fragmented, the source |
| node generates an Identification value that is present |
| in all the fragments */ |
| #define IP_MF 0x0001 |
| |
| static uint16_t |
| uip_reass(void) |
| { |
| uint16_t offset=0; |
| uint16_t len; |
| uint16_t i; |
| |
| /* If ip_reasstmr is zero, no packet is present in the buffer */ |
| /* We first write the unfragmentable part of IP header into the reassembly |
| buffer. The reset the other reassembly variables. */ |
| if(uip_reass_on == 0) { |
| PRINTF("Starting reassembly\n"); |
| memcpy(FBUF, UIP_IP_BUF(buf), uip_ext_len(buf) + UIP_IPH_LEN); |
| /* temporary in case we do not receive the fragment with offset 0 first */ |
| etimer_set(&uip_reass_timer, UIP_REASS_MAXAGE*CLOCK_SECOND, &tcpip_process); |
| uip_reass_on = 1; |
| uip_reassflags = 0; |
| uip_id = UIP_FRAG_BUF->id; |
| /* 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(uip_ipaddr_cmp(&FBUF->srcipaddr, &UIP_IP_BUF(buf)->srcipaddr) && |
| uip_ipaddr_cmp(&FBUF->destipaddr, &UIP_IP_BUF(buf)->destipaddr) && |
| UIP_FRAG_BUF->id == uip_id) { |
| len = uip_len(buf) - uip_ext_len(buf) - UIP_IPH_LEN - UIP_FRAGH_LEN; |
| offset = (uip_ntohs(UIP_FRAG_BUF->offsetresmore) & 0xfff8); |
| /* in byte, originaly in multiple of 8 bytes*/ |
| PRINTF("len %d\n", len); |
| PRINTF("offset %d\n", offset); |
| if(offset == 0){ |
| uip_reassflags |= UIP_REASS_FLAG_FIRSTFRAG; |
| /* |
| * The Next Header field of the last header of the Unfragmentable |
| * Part is obtained from the Next Header field of the first |
| * fragment's Fragment header. |
| */ |
| *uip_next_hdr = UIP_FRAG_BUF->next; |
| memcpy(FBUF, UIP_IP_BUF(buf), uip_ext_len(buf) + UIP_IPH_LEN); |
| PRINTF("src "); |
| PRINT6ADDR(&FBUF->srcipaddr); |
| PRINTF("dest "); |
| PRINT6ADDR(&FBUF->destipaddr); |
| PRINTF("next %d\n", UIP_IP_BUF(buf)->proto); |
| |
| } |
| |
| /* 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_reass_on = 0; |
| etimer_stop(&uip_reass_timer); |
| return 0; |
| } |
| |
| /* If this fragment has the More Fragments flag set to zero, it is the |
| last fragment*/ |
| if((uip_ntohs(UIP_FRAG_BUF->offsetresmore) & IP_MF) == 0) { |
| uip_reassflags |= UIP_REASS_FLAG_LASTFRAG; |
| /*calculate the size of the entire packet*/ |
| uip_reasslen = offset + len; |
| PRINTF("LAST FRAGMENT reasslen %d\n", uip_reasslen); |
| } else { |
| /* If len is not a multiple of 8 octets and the M flag of that fragment |
| is 1, then that fragment must be discarded and an ICMP Parameter |
| Problem, Code 0, message should be sent to the source of the fragment, |
| pointing to the Payload Length field of the fragment packet. */ |
| if(len % 8 != 0){ |
| uip_icmp6_error_output(ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, 4); |
| uip_reassflags |= UIP_REASS_FLAG_ERROR_MSG; |
| /* not clear if we should interrupt reassembly, but it seems so from |
| the conformance tests */ |
| uip_reass_on = 0; |
| etimer_stop(&uip_reass_timer); |
| return uip_len(buf); |
| } |
| } |
| |
| /* Copy the fragment into the reassembly buffer, at the right |
| offset. */ |
| memcpy((uint8_t *)FBUF + UIP_IPH_LEN + uip_ext_len(buf) + offset, |
| (uint8_t *)UIP_FRAG_BUF + UIP_FRAGH_LEN, len); |
| |
| /* Update the bitmap. */ |
| if(offset >> 6 == (offset + len) >> 6) { |
| uip_reassbitmap[offset >> 6] |= |
| bitmap_bits[(offset >> 3) & 7] & |
| ~bitmap_bits[((offset + len) >> 3) & 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 >> 6] |= bitmap_bits[(offset >> 3) & 7]; |
| |
| for(i = (1 + (offset >> 6)); i < ((offset + len) >> 6); ++i) { |
| uip_reassbitmap[i] = 0xff; |
| } |
| uip_reassbitmap[(offset + len) >> 6] |= |
| ~bitmap_bits[((offset + len) >> 3) & 7]; |
| } |
| |
| /* 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 >> 6); ++i) { |
| if(uip_reassbitmap[i] != 0xff) { |
| return 0; |
| } |
| } |
| /* Check the last byte in the bitmap. It should contain just the |
| right amount of bits. */ |
| if(uip_reassbitmap[uip_reasslen >> 6] != |
| (uint8_t)~bitmap_bits[(uip_reasslen >> 3) & 7]) { |
| return 0; |
| } |
| |
| /* If we have come this far, we have a full packet in the |
| buffer, so we copy it to uip_buf. We also reset the timer. */ |
| uip_reass_on = 0; |
| etimer_stop(&uip_reass_timer); |
| |
| uip_reasslen += UIP_IPH_LEN + uip_ext_len(buf); |
| memcpy(UIP_IP_BUF(buf), FBUF, uip_reasslen); |
| UIP_IP_BUF(buf)->len[0] = ((uip_reasslen - UIP_IPH_LEN) >> 8); |
| UIP_IP_BUF(buf)->len[1] = ((uip_reasslen - UIP_IPH_LEN) & 0xff); |
| PRINTF("REASSEMBLED PAQUET %d (%d)\n", uip_reasslen, |
| (UIP_IP_BUF(buf)->len[0] << 8) | UIP_IP_BUF(buf)->len[1]); |
| |
| return uip_reasslen; |
| |
| } |
| } else { |
| PRINTF("Already reassembling another paquet\n"); |
| } |
| return 0; |
| } |
| |
| void |
| uip_reass_over(struct net_buf *buf) |
| { |
| /* to late, we abandon the reassembly of the packet */ |
| |
| uip_reass_on = 0; |
| etimer_stop(&uip_reass_timer); |
| |
| if(uip_reassflags & UIP_REASS_FLAG_FIRSTFRAG){ |
| PRINTF("FRAG INTERRUPTED TOO LATE\n"); |
| /* If the first fragment has been received, an ICMP Time Exceeded |
| -- Fragment Reassembly Time Exceeded message should be sent to the |
| source of that fragment. */ |
| /** \note |
| * We don't have a complete packet to put in the error message. |
| * We could include the first fragment but since its not mandated by |
| * any RFC, we decided not to include it as it reduces the size of |
| * the packet. |
| */ |
| uip_len(buf) = 0; |
| uip_ext_len(buf) = 0; |
| memcpy(UIP_IP_BUF(buf), FBUF, UIP_IPH_LEN); /* copy the header for src |
| and dest address*/ |
| uip_icmp6_error_output(ICMP6_TIME_EXCEEDED, ICMP6_TIME_EXCEED_REASSEMBLY, 0); |
| |
| UIP_STAT(++uip_stat.ip.sent); |
| uip_flags(buf) = 0; |
| } |
| } |
| |
| #endif /* UIP_CONF_IPV6_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 |
| /*---------------------------------------------------------------------------*/ |
| |
| /** |
| * \brief Process the options in Destination and Hop By Hop extension headers |
| */ |
| static uint8_t |
| ext_hdr_options_process(struct net_buf *buf) |
| { |
| /* |
| * Length field in the extension header: length of the header in units of |
| * 8 bytes, excluding the first 8 bytes |
| * length field in an option : the length of data in the option |
| */ |
| if (((UIP_EXT_BUF(buf)->len << 3) + 8) > buf->len) { |
| PRINTF("Corrupted packet, extension header %d too long (max %d bytes)\n", |
| (UIP_EXT_BUF(buf)->len << 3) + 8, buf->len); |
| return 1; /* invalid packet, drop it */ |
| } |
| |
| uip_ext_opt_offset(buf) = 2; |
| while(uip_ext_opt_offset(buf) < ((UIP_EXT_BUF(buf)->len << 3) + 8)) { |
| switch(UIP_EXT_HDR_OPT_BUF(buf)->type) { |
| /* |
| * for now we do not support any options except padding ones |
| * PAD1 does not make sense as the header must be 8bytes aligned, |
| * hence we can only have |
| */ |
| case UIP_EXT_HDR_OPT_PAD1: |
| PRINTF("Processing PAD1 option\n"); |
| uip_ext_opt_offset(buf) += 1; |
| break; |
| case UIP_EXT_HDR_OPT_PADN: |
| PRINTF("Processing PADN option\n"); |
| uip_ext_opt_offset(buf) += UIP_EXT_HDR_OPT_PADN_BUF(buf)->opt_len + 2; |
| break; |
| case UIP_EXT_HDR_OPT_RPL: |
| /* Fixes situation when a node that is not using RPL |
| * joins a network which does. The received packages will include the |
| * RPL header and processed by the "default" case of the switch |
| * (0x63 & 0xC0 = 0x40). Hence, the packet is discarded as the header |
| * is considered invalid. |
| * Using this fix, the header is ignored, and the next header (if |
| * present) is processed. |
| */ |
| #if UIP_CONF_IPV6_RPL |
| PRINTF("Processing RPL option\n"); |
| if(rpl_verify_header(buf, uip_ext_opt_offset(buf))) { |
| PRINTF("RPL Option Error: Dropping Packet\n"); |
| return 1; |
| } |
| #endif /* UIP_CONF_IPV6_RPL */ |
| uip_ext_opt_offset(buf) += (UIP_EXT_HDR_OPT_BUF(buf)->len) + 2; |
| return 0; |
| default: |
| /* |
| * check the two highest order bits of the option |
| * - 00 skip over this option and continue processing the header. |
| * - 01 discard the packet. |
| * - 10 discard the packet and, regardless of whether or not the |
| * packet's Destination Address was a multicast address, send an |
| * ICMP Parameter Problem, Code 2, message to the packet's |
| * Source Address, pointing to the unrecognized Option Type. |
| * - 11 discard the packet and, only if the packet's Destination |
| * Address was not a multicast address, send an ICMP Parameter |
| * Problem, Code 2, message to the packet's Source Address, |
| * pointing to the unrecognized Option Type. |
| */ |
| PRINTF("MSB %x\n", UIP_EXT_HDR_OPT_BUF(buf)->type); |
| switch(UIP_EXT_HDR_OPT_BUF(buf)->type & 0xC0) { |
| case 0: |
| break; |
| case 0x40: |
| return 1; |
| case 0xC0: |
| if(uip_is_addr_mcast(&UIP_IP_BUF(buf)->destipaddr)) { |
| return 1; |
| } |
| case 0x80: |
| uip_icmp6_error_output(buf, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, |
| (uint32_t)UIP_IPH_LEN + uip_ext_len(buf) + uip_ext_opt_offset(buf)); |
| return 2; |
| } |
| /* in the cases were we did not discard, update ext_opt* */ |
| uip_ext_opt_offset(buf) += UIP_EXT_HDR_OPT_BUF(buf)->len + 2; |
| break; |
| } |
| } |
| return 0; |
| } |
| |
| |
| /*---------------------------------------------------------------------------*/ |
| uint8_t |
| uip_process(struct net_buf *buf, uint8_t flag) |
| { |
| #if UIP_TCP |
| register struct uip_conn *uip_connr = uip_conn(buf); |
| uint8_t c; |
| #endif /* UIP_TCP */ |
| #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((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) { |
| /* In the SYN_SENT state, we retransmit out SYN. */ |
| UIP_TCP_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\n", |
| uip_len(buf), uip_outstanding(uip_connr)); |
| return 0; |
| } |
| } |
| goto drop; |
| } |
| #else /* TCP */ |
| if(flag == UIP_POLL_REQUEST) { |
| goto drop; |
| } |
| #endif /* UIP_TCP */ |
| /* Check if we were invoked because of the perodic timer fireing. */ |
| if(flag == UIP_TIMER) { |
| /* Reset the length variables. */ |
| #if UIP_TCP |
| uip_len(buf) = 0; |
| uip_slen(buf) = 0; |
| |
| /* Increase the initial sequence number. */ |
| if(++iss[3] == 0) { |
| if(++iss[2] == 0) { |
| if(++iss[1] == 0) { |
| ++iss[0]; |
| } |
| } |
| } |
| |
| /* |
| * 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 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. */ |
| UIP_TCP_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. */ |
| UIP_TCP_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; |
| } |
| } |
| goto drop; |
| #endif /* UIP_TCP */ |
| } |
| #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_IPUDPH_LEN + UIP_LLH_LEN]; |
| uip_len(buf) = uip_slen(buf) = 0; |
| uip_flags(buf) = UIP_POLL; |
| UIP_UDP_APPCALL(buf); |
| goto udp_send; |
| } else { |
| goto drop; |
| } |
| } |
| #endif /* UIP_UDP */ |
| |
| |
| /* This is where the input processing starts. */ |
| UIP_STAT(++uip_stat.ip.recv); |
| |
| /* Start of IP input header processing code. */ |
| |
| /* Check validity of the IP header. */ |
| if((UIP_IP_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; |
| } |
| /* |
| * 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((UIP_IP_BUF(buf)->len[0] << 8) + UIP_IP_BUF(buf)->len[1] <= uip_len(buf)) { |
| uip_len(buf) = (UIP_IP_BUF(buf)->len[0] << 8) + UIP_IP_BUF(buf)->len[1] + UIP_IPH_LEN; |
| /* |
| * 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). |
| */ |
| } else { |
| UIP_LOG("ip: packet shorter than reported in IP header."); |
| PRINTF("IPv6 packet size %d buf len %d\n", |
| (UIP_IP_BUF(buf)->len[0] << 8) + UIP_IP_BUF(buf)->len[1], |
| uip_len(buf)); |
| goto drop; |
| } |
| |
| PRINTF("IPv6 packet received from "); |
| PRINT6ADDR(&UIP_IP_BUF(buf)->srcipaddr); |
| PRINTF(" to "); |
| PRINT6ADDR(&UIP_IP_BUF(buf)->destipaddr); |
| PRINTF("\n"); |
| |
| if(uip_is_addr_mcast(&UIP_IP_BUF(buf)->srcipaddr)){ |
| UIP_STAT(++uip_stat.ip.drop); |
| PRINTF("Dropping packet, src is mcast\n"); |
| goto drop; |
| } |
| |
| #if UIP_CONF_ROUTER |
| /* |
| * Next header field processing. In IPv6, we can have extension headers, |
| * if present, the Hop-by-Hop Option must be processed before forwarding |
| * the packet. |
| */ |
| uip_next_hdr = &UIP_IP_BUF->proto; |
| uip_ext_len(buf) = 0; |
| uip_ext_bitmap = 0; |
| if(*uip_next_hdr == UIP_PROTO_HBHO) { |
| #if UIP_CONF_IPV6_CHECKS |
| uip_ext_bitmap |= UIP_EXT_HDR_BITMAP_HBHO; |
| #endif /* UIP_CONF_IPV6_CHECKS */ |
| switch(ext_hdr_options_process()) { |
| case 0: |
| /* continue */ |
| uip_next_hdr = &UIP_EXT_BUF->next; |
| uip_ext_len(buf) += (UIP_EXT_BUF->len << 3) + 8; |
| break; |
| case 1: |
| PRINTF("Dropping packet after extension header processing\n"); |
| /* silently discard */ |
| goto drop; |
| case 2: |
| PRINTF("Sending error message after extension header processing\n"); |
| /* send icmp error message (created in ext_hdr_options_process) |
| * and discard*/ |
| goto send; |
| } |
| } |
| |
| /* |
| * Process Packets with a routable multicast destination: |
| * - We invoke the multicast engine and let it do its thing |
| * (cache, forward etc). |
| * - We never execute the datagram forwarding logic in this file here. When |
| * the engine returns, forwarding has been handled if and as required. |
| * - Depending on the return value, we either discard or deliver up the stack |
| * |
| * All multicast engines must hook in here. After this function returns, we |
| * expect UIP_BUF to be unmodified |
| */ |
| #if UIP_CONF_IPV6_MULTICAST |
| if(uip_is_addr_mcast_routable(&UIP_IP_BUF->destipaddr)) { |
| if(UIP_MCAST6.in() == UIP_MCAST6_ACCEPT) { |
| /* Deliver up the stack */ |
| goto process; |
| } else { |
| /* Don't deliver up the stack */ |
| goto drop; |
| } |
| } |
| #endif /* UIP_IPV6_CONF_MULTICAST */ |
| |
| /* TBD Some Parameter problem messages */ |
| if(!uip_ds6_is_my_addr(&UIP_IP_BUF->destipaddr) && |
| !uip_ds6_is_my_maddr(&UIP_IP_BUF->destipaddr)) { |
| if(!uip_is_addr_mcast(&UIP_IP_BUF->destipaddr) && |
| !uip_is_addr_link_local(&UIP_IP_BUF->destipaddr) && |
| !uip_is_addr_link_local(&UIP_IP_BUF->srcipaddr) && |
| !uip_is_addr_unspecified(&UIP_IP_BUF->srcipaddr) && |
| !uip_is_addr_loopback(&UIP_IP_BUF->destipaddr)) { |
| |
| |
| /* Check MTU */ |
| if(uip_len > UIP_LINK_MTU) { |
| uip_icmp6_error_output(ICMP6_PACKET_TOO_BIG, 0, UIP_LINK_MTU); |
| UIP_STAT(++uip_stat.ip.drop); |
| goto send; |
| } |
| /* Check Hop Limit */ |
| if(UIP_IP_BUF->ttl <= 1) { |
| uip_icmp6_error_output(ICMP6_TIME_EXCEEDED, |
| ICMP6_TIME_EXCEED_TRANSIT, 0); |
| UIP_STAT(++uip_stat.ip.drop); |
| goto send; |
| } |
| |
| #if UIP_CONF_IPV6_RPL |
| if(rpl_update_header_empty()) { |
| /* Packet can not be forwarded */ |
| PRINTF("RPL Forward Option Error\n"); |
| goto drop; |
| } |
| #endif /* UIP_CONF_IPV6_RPL */ |
| |
| UIP_IP_BUF->ttl = UIP_IP_BUF->ttl - 1; |
| PRINTF("Forwarding packet to "); |
| PRINT6ADDR(&UIP_IP_BUF->destipaddr); |
| PRINTF("\n"); |
| UIP_STAT(++uip_stat.ip.forwarded); |
| goto send; |
| } else { |
| if((uip_is_addr_link_local(&UIP_IP_BUF->srcipaddr)) && |
| (!uip_is_addr_unspecified(&UIP_IP_BUF->srcipaddr)) && |
| (!uip_is_addr_loopback(&UIP_IP_BUF->destipaddr)) && |
| (!uip_is_addr_mcast(&UIP_IP_BUF->destipaddr)) && |
| (!uip_ds6_is_addr_onlink((&UIP_IP_BUF->destipaddr)))) { |
| PRINTF("LL source address with off link destination, dropping\n"); |
| uip_icmp6_error_output(ICMP6_DST_UNREACH, |
| ICMP6_DST_UNREACH_NOTNEIGHBOR, 0); |
| goto send; |
| } |
| PRINTF("Dropping packet, not for me and link local or multicast\n"); |
| UIP_STAT(++uip_stat.ip.drop); |
| goto drop; |
| } |
| } |
| #else /* UIP_CONF_ROUTER */ |
| if(!uip_ds6_is_my_addr(&UIP_IP_BUF(buf)->destipaddr) && |
| !uip_ds6_is_my_maddr(&UIP_IP_BUF(buf)->destipaddr) && |
| !uip_is_addr_mcast(&UIP_IP_BUF(buf)->destipaddr) && |
| !uip_is_addr_loopback(&UIP_IP_BUF(buf)->destipaddr)) { |
| PRINTF("Dropping packet, not for me\n"); |
| UIP_STAT(++uip_stat.ip.drop); |
| goto drop; |
| } |
| |
| /* |
| * Next header field processing. In IPv6, we can have extension headers, |
| * they are processed here |
| */ |
| uip_next_hdr(buf) = &UIP_IP_BUF(buf)->proto; |
| uip_ext_len(buf) = 0; |
| uip_ext_bitmap(buf) = 0; |
| #endif /* UIP_CONF_ROUTER */ |
| |
| #if UIP_CONF_ROUTER |
| #if UIP_CONF_IPV6_MULTICAST |
| process: |
| #endif |
| #endif |
| |
| while(1) { |
| switch(*(uip_next_hdr(buf))){ |
| #if UIP_TCP |
| case UIP_PROTO_TCP: |
| /* TCP, for both IPv4 and IPv6 */ |
| goto tcp_input; |
| #endif /* UIP_TCP */ |
| #if UIP_UDP |
| case UIP_PROTO_UDP: |
| /* UDP, for both IPv4 and IPv6 */ |
| goto udp_input; |
| #endif /* UIP_UDP */ |
| case UIP_PROTO_ICMP6: |
| /* ICMPv6 */ |
| goto icmp6_input; |
| case UIP_PROTO_HBHO: |
| PRINTF("Processing hbh header\n"); |
| /* Hop by hop option header */ |
| #if UIP_CONF_IPV6_CHECKS |
| /* Hop by hop option header. If we saw one HBH already, drop */ |
| if(uip_ext_bitmap(buf) & UIP_EXT_HDR_BITMAP_HBHO) { |
| goto bad_hdr; |
| } else { |
| uip_ext_bitmap(buf) |= UIP_EXT_HDR_BITMAP_HBHO; |
| } |
| #endif /*UIP_CONF_IPV6_CHECKS*/ |
| switch(ext_hdr_options_process(buf)) { |
| case 0: |
| /*continue*/ |
| uip_next_hdr(buf) = &UIP_EXT_BUF(buf)->next; |
| uip_ext_len(buf) += (UIP_EXT_BUF(buf)->len << 3) + 8; |
| break; |
| case 1: |
| /*silently discard*/ |
| goto drop; |
| case 2: |
| /* send icmp error message (created in ext_hdr_options_process) |
| * and discard*/ |
| goto send; |
| } |
| break; |
| case UIP_PROTO_DESTO: |
| #if UIP_CONF_IPV6_CHECKS |
| /* Destination option header. if we saw two already, drop */ |
| PRINTF("Processing desto header\n"); |
| if(uip_ext_bitmap(buf) & UIP_EXT_HDR_BITMAP_DESTO1) { |
| if(uip_ext_bitmap(buf) & UIP_EXT_HDR_BITMAP_DESTO2) { |
| goto bad_hdr; |
| } else{ |
| uip_ext_bitmap(buf) |= UIP_EXT_HDR_BITMAP_DESTO2; |
| } |
| } else { |
| uip_ext_bitmap(buf) |= UIP_EXT_HDR_BITMAP_DESTO1; |
| } |
| #endif /*UIP_CONF_IPV6_CHECKS*/ |
| switch(ext_hdr_options_process(buf)) { |
| case 0: |
| /*continue*/ |
| uip_next_hdr(buf) = &UIP_EXT_BUF(buf)->next; |
| uip_ext_len(buf) += (UIP_EXT_BUF(buf)->len << 3) + 8; |
| break; |
| case 1: |
| /*silently discard*/ |
| goto drop; |
| case 2: |
| /* send icmp error message (created in ext_hdr_options_process) |
| * and discard*/ |
| goto send; |
| } |
| break; |
| case UIP_PROTO_ROUTING: |
| #if UIP_CONF_IPV6_CHECKS |
| /* Routing header. If we saw one already, drop */ |
| if(uip_ext_bitmap(buf) & UIP_EXT_HDR_BITMAP_ROUTING) { |
| goto bad_hdr; |
| } else { |
| uip_ext_bitmap(buf) |= UIP_EXT_HDR_BITMAP_ROUTING; |
| } |
| #endif /*UIP_CONF_IPV6_CHECKS*/ |
| /* |
| * Routing Header length field is in units of 8 bytes, excluding |
| * As per RFC2460 section 4.4, if routing type is unrecognized: |
| * if segments left = 0, ignore the header |
| * if segments left > 0, discard packet and send icmp error pointing |
| * to the routing type |
| */ |
| |
| PRINTF("Processing Routing header\n"); |
| if(UIP_ROUTING_BUF(buf)->seg_left > 0) { |
| uip_icmp6_error_output(buf, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, UIP_IPH_LEN + uip_ext_len(buf) + 2); |
| UIP_STAT(++uip_stat.ip.drop); |
| UIP_LOG("ip6: unrecognized routing type"); |
| goto send; |
| } |
| uip_next_hdr(buf) = &UIP_EXT_BUF(buf)->next; |
| uip_ext_len(buf) += (UIP_EXT_BUF(buf)->len << 3) + 8; |
| break; |
| case UIP_PROTO_FRAG: |
| /* Fragmentation header:call the reassembly function, then leave */ |
| #if UIP_CONF_IPV6_REASSEMBLY |
| PRINTF("Processing frag header\n"); |
| uip_len(buf) = uip_reass(); |
| if(uip_len(buf) == 0) { |
| goto drop; |
| } |
| if(uip_reassflags & UIP_REASS_FLAG_ERROR_MSG){ |
| /* we are not done with reassembly, this is an error message */ |
| goto send; |
| } |
| /*packet is reassembled, reset the next hdr to the beginning |
| of the IP header and restart the parsing of the reassembled pkt*/ |
| PRINTF("Processing reassembled packet\n"); |
| uip_ext_len(buf) = 0; |
| uip_ext_bitmap(buf) = 0; |
| uip_next_hdr(buf) = &UIP_IP_BUF(buf)->proto; |
| break; |
| #else /* UIP_CONF_IPV6_REASSEMBLY */ |
| UIP_STAT(++uip_stat.ip.drop); |
| UIP_STAT(++uip_stat.ip.fragerr); |
| UIP_LOG("ip: fragment dropped."); |
| goto drop; |
| #endif /* UIP_CONF_IPV6_REASSEMBLY */ |
| case UIP_PROTO_NONE: |
| goto drop; |
| default: |
| goto bad_hdr; |
| } |
| } |
| bad_hdr: |
| /* |
| * RFC 2460 send error message parameterr problem, code unrecognized |
| * next header, pointing to the next header field |
| */ |
| uip_icmp6_error_output(buf, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_NEXTHEADER, (uint32_t)(uip_next_hdr(buf) - (uint8_t *)UIP_IP_BUF(buf))); |
| UIP_STAT(++uip_stat.ip.drop); |
| UIP_STAT(++uip_stat.ip.protoerr); |
| UIP_LOG("ip6: unrecognized header"); |
| goto send; |
| /* End of headers processing */ |
| |
| icmp6_input: |
| /* This is IPv6 ICMPv6 processing code. */ |
| PRINTF("icmp6_input: length %d type: %d \n", uip_len(buf), UIP_ICMP_BUF(buf)->type); |
| |
| #if UIP_CONF_IPV6_CHECKS |
| /* Compute and check the ICMP header checksum */ |
| if(uip_icmp6chksum(buf) != 0xffff) { |
| UIP_STAT(++uip_stat.icmp.drop); |
| UIP_STAT(++uip_stat.icmp.chkerr); |
| UIP_LOG("icmpv6: bad checksum."); |
| PRINTF("icmpv6: bad checksum."); |
| goto drop; |
| } |
| #endif /*UIP_CONF_IPV6_CHECKS*/ |
| |
| UIP_STAT(++uip_stat.icmp.recv); |
| /* |
| * Here we process incoming ICMPv6 packets |
| * For echo request, we send echo reply |
| * For ND pkts, we call the appropriate function in uip-nd6.c |
| * We do not treat Error messages for now |
| * If no pkt is to be sent as an answer to the incoming one, we |
| * "goto drop". Else we just break; then at the after the "switch" |
| * we "goto send" |
| */ |
| #if UIP_CONF_ICMP6 |
| UIP_ICMP6_APPCALL(UIP_ICMP_BUF(buf)->type); |
| #endif /*UIP_CONF_ICMP6*/ |
| |
| /* |
| * Search generic input handlers. |
| * The handler is in charge of setting uip_len to 0 |
| */ |
| if(uip_icmp6_input(buf, UIP_ICMP_BUF(buf)->type, |
| UIP_ICMP_BUF(buf)->icode) == UIP_ICMP6_INPUT_ERROR) { |
| PRINTF("Unknown ICMPv6 message type/code %d\n", UIP_ICMP_BUF(buf)->type); |
| UIP_STAT(++uip_stat.icmp.drop); |
| UIP_STAT(++uip_stat.icmp.typeerr); |
| UIP_LOG("icmp6: unknown ICMPv6 message."); |
| uip_len(buf) = 0; |
| } |
| |
| if(uip_len(buf) > 0) { |
| goto send; |
| } else { |
| goto drop; |
| } |
| /* End of IPv6 ICMP processing. */ |
| |
| |
| #if UIP_UDP |
| /* UDP input processing. */ |
| udp_input: |
| |
| remove_ext_hdr(buf); |
| |
| PRINTF("Receiving UDP packet\n"); |
| |
| /* 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(buf) = uip_len(buf) - UIP_IPUDPH_LEN; |
| uip_appdata(buf) = &uip_buf(buf)[UIP_IPUDPH_LEN + UIP_LLH_LEN]; |
| /* XXX hack: UDP/IPv6 receivers should drop packets with UDP |
| checksum 0. Here, we explicitly receive UDP packets with checksum |
| 0. This is to be able to debug code that for one reason or |
| another miscomputes UDP checksums. The reception of zero UDP |
| checksums should be turned into a configration option. */ |
| if(UIP_UDP_BUF(buf)->udpchksum != 0 && uip_udpchksum(buf) != 0xffff) { |
| UIP_STAT(++uip_stat.udp.drop); |
| UIP_STAT(++uip_stat.udp.chkerr); |
| PRINTF("udp: bad checksum 0x%04x 0x%04x\n", UIP_UDP_BUF(buf)->udpchksum, |
| uip_udpchksum(buf)); |
| 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(UIP_UDP_BUF(buf)->destport == 0) { |
| PRINTF("udp: zero port.\n"); |
| goto drop; |
| } |
| |
| /* Demultiplex this UDP packet between the UDP "connections". */ |
| for(i = 0; i < UIP_UDP_CONNS; i++) { |
| /* 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 0 |
| PRINTF("%d: %p lport %d <- %d rport %d <- %d addr ", |
| i, &uip_udp_conns[i], |
| uip_ntohs(uip_udp_conns[i].lport), uip_ntohs(UIP_UDP_BUF(buf)->destport), |
| uip_ntohs(uip_udp_conns[i].rport), uip_ntohs(UIP_UDP_BUF(buf)->srcport)); |
| PRINT6ADDR(&uip_udp_conns[i].ripaddr); |
| PRINTF(" <- "); |
| PRINT6ADDR(&UIP_IP_BUF(buf)->srcipaddr); |
| PRINTF("\n"); |
| #endif /* 0 */ |
| if(uip_udp_conns[i].lport != 0 && |
| UIP_UDP_BUF(buf)->destport == uip_udp_conns[i].lport && |
| (uip_udp_conns[i].rport == 0 || |
| UIP_UDP_BUF(buf)->srcport == uip_udp_conns[i].rport) && |
| (uip_is_addr_unspecified(&uip_udp_conns[i].ripaddr) || |
| uip_ipaddr_cmp(&UIP_IP_BUF(buf)->srcipaddr, &uip_udp_conns[i].ripaddr))) { |
| uip_set_udp_conn(buf) = &uip_udp_conns[i]; |
| goto udp_found; |
| } |
| } |
| uip_set_udp_conn(buf) = NULL; |
| PRINTF("udp: no matching connection found\n"); |
| UIP_STAT(++uip_stat.udp.drop); |
| |
| #if UIP_UDP_SEND_UNREACH_NOPORT |
| uip_icmp6_error_output(buf, ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0); |
| goto send; |
| #else |
| uip_len(buf) = 0; |
| goto drop; |
| #endif |
| |
| 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_IPUDPH_LEN + UIP_LLH_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. Returning 0 here |
| * will mean that tcpip.c:packet_input() will not try to call |
| * tcpip_ipv6_output(). |
| */ |
| 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; |
| |
| /* For IPv6, the IP length field does not include the IPv6 IP header |
| length. */ |
| UIP_IP_BUF(buf)->len[0] = ((uip_len(buf) - UIP_IPH_LEN) >> 8); |
| UIP_IP_BUF(buf)->len[1] = ((uip_len(buf) - UIP_IPH_LEN) & 0xff); |
| |
| UIP_IP_BUF(buf)->ttl = uip_udp_conn(buf)->ttl; |
| UIP_IP_BUF(buf)->proto = UIP_PROTO_UDP; |
| |
| UIP_UDP_BUF(buf)->udplen = UIP_HTONS(uip_slen(buf) + UIP_UDPH_LEN); |
| UIP_UDP_BUF(buf)->udpchksum = 0; |
| |
| UIP_UDP_BUF(buf)->srcport = uip_udp_conn(buf)->lport; |
| UIP_UDP_BUF(buf)->destport = uip_udp_conn(buf)->rport; |
| |
| uip_ipaddr_copy(&UIP_IP_BUF(buf)->destipaddr, &uip_udp_conn(buf)->ripaddr); |
| uip_ds6_select_src(&UIP_IP_BUF(buf)->srcipaddr, &UIP_IP_BUF(buf)->destipaddr); |
| |
| uip_appdata(buf) = &uip_buf(buf)[UIP_LLH_LEN + UIP_IPTCPH_LEN]; |
| |
| #if UIP_UDP_CHECKSUMS |
| /* Calculate UDP checksum. */ |
| UIP_UDP_BUF(buf)->udpchksum = ~(uip_udpchksum(buf)); |
| if(UIP_UDP_BUF(buf)->udpchksum == 0) { |
| UIP_UDP_BUF(buf)->udpchksum = 0xffff; |
| } |
| #endif /* UIP_UDP_CHECKSUMS */ |
| |
| #if UIP_CONF_IPV6_RPL |
| rpl_insert_header(buf); |
| #endif /* UIP_CONF_IPV6_RPL */ |
| |
| UIP_STAT(++uip_stat.udp.sent); |
| goto ip_send_nolen; |
| #endif /* UIP_UDP */ |
| |
| #if UIP_TCP |
| /* TCP input processing. */ |
| tcp_input: |
| |
| remove_ext_hdr(buf); |
| |
| UIP_STAT(++uip_stat.tcp.recv); |
| PRINTF("Receiving TCP packet\n"); |
| /* 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); |
| PRINTF("tcp: bad checksum 0x%04x 0x%04x\n", UIP_TCP_BUF(buf)->tcpchksum, |
| uip_tcpchksum(buf)); |
| goto drop; |
| } |
| |
| /* Make sure that the TCP port number is not zero. */ |
| if(UIP_TCP_BUF(buf)->destport == 0 || UIP_TCP_BUF(buf)->srcport == 0) { |
| PRINTF("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 && |
| UIP_TCP_BUF(buf)->destport == uip_connr->lport && |
| UIP_TCP_BUF(buf)->srcport == uip_connr->rport && |
| uip_ipaddr_cmp(&UIP_IP_BUF(buf)->srcipaddr, &uip_connr->ripaddr)) { |
| goto found; |
| } |
| } |
| |
| /* If we didn't find and 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((UIP_TCP_BUF(buf)->flags & TCP_CTL) != TCP_SYN) { |
| goto reset; |
| } |
| |
| tmp16 = UIP_TCP_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: |
| PRINTF("In reset\n"); |
| /* We do not send resets in response to resets. */ |
| if(UIP_TCP_BUF(buf)->flags & TCP_RST) { |
| goto drop; |
| } |
| |
| UIP_STAT(++uip_stat.tcp.rst); |
| |
| UIP_TCP_BUF(buf)->flags = TCP_RST | TCP_ACK; |
| uip_len(buf) = UIP_IPTCPH_LEN; |
| UIP_TCP_BUF(buf)->tcpoffset = 5 << 4; |
| |
| /* Flip the seqno and ackno fields in the TCP header. */ |
| c = UIP_TCP_BUF(buf)->seqno[3]; |
| UIP_TCP_BUF(buf)->seqno[3] = UIP_TCP_BUF(buf)->ackno[3]; |
| UIP_TCP_BUF(buf)->ackno[3] = c; |
| |
| c = UIP_TCP_BUF(buf)->seqno[2]; |
| UIP_TCP_BUF(buf)->seqno[2] = UIP_TCP_BUF(buf)->ackno[2]; |
| UIP_TCP_BUF(buf)->ackno[2] = c; |
| |
| c = UIP_TCP_BUF(buf)->seqno[1]; |
| UIP_TCP_BUF(buf)->seqno[1] = UIP_TCP_BUF(buf)->ackno[1]; |
| UIP_TCP_BUF(buf)->ackno[1] = c; |
| |
| c = UIP_TCP_BUF(buf)->seqno[0]; |
| UIP_TCP_BUF(buf)->seqno[0] = UIP_TCP_BUF(buf)->ackno[0]; |
| UIP_TCP_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(++UIP_TCP_BUF(buf)->ackno[3] == 0) { |
| if(++UIP_TCP_BUF(buf)->ackno[2] == 0) { |
| if(++UIP_TCP_BUF(buf)->ackno[1] == 0) { |
| ++UIP_TCP_BUF(buf)->ackno[0]; |
| } |
| } |
| } |
| |
| /* Swap port numbers. */ |
| tmp16 = UIP_TCP_BUF(buf)->srcport; |
| UIP_TCP_BUF(buf)->srcport = UIP_TCP_BUF(buf)->destport; |
| UIP_TCP_BUF(buf)->destport = tmp16; |
| |
| /* Swap IP addresses. */ |
| uip_ipaddr_copy(&UIP_IP_BUF(buf)->destipaddr, &UIP_IP_BUF(buf)->srcipaddr); |
| uip_ds6_select_src(&UIP_IP_BUF(buf)->srcipaddr, &UIP_IP_BUF(buf)->destipaddr); |
| /* 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 = UIP_TCP_BUF(buf)->destport; |
| uip_connr->rport = UIP_TCP_BUF(buf)->srcport; |
| uip_ipaddr_copy(&uip_connr->ripaddr, &UIP_IP_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; |
| |
| /* rcv_nxt should be the seqno from the incoming packet + 1. */ |
| uip_connr->rcv_nxt[3] = UIP_TCP_BUF(buf)->seqno[3]; |
| uip_connr->rcv_nxt[2] = UIP_TCP_BUF(buf)->seqno[2]; |
| uip_connr->rcv_nxt[1] = UIP_TCP_BUF(buf)->seqno[1]; |
| uip_connr->rcv_nxt[0] = UIP_TCP_BUF(buf)->seqno[0]; |
| uip_add_rcv_nxt(buf, 1); |
| |
| /* Parse the TCP MSS option, if present. */ |
| if((UIP_TCP_BUF(buf)->tcpoffset & 0xf0) > 0x50) { |
| for(c = 0; c < ((UIP_TCP_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: |
| UIP_TCP_BUF(buf)->flags = TCP_ACK; |
| |
| tcp_send_syn: |
| UIP_TCP_BUF(buf)->flags |= TCP_SYN; |
| #else /* UIP_ACTIVE_OPEN */ |
| tcp_send_synack: |
| UIP_TCP_BUF(buf)->flags = TCP_SYN | TCP_ACK; |
| #endif /* UIP_ACTIVE_OPEN */ |
| |
| /* We send out the TCP Maximum Segment Size option with our |
| SYNACK. */ |
| UIP_TCP_BUF(buf)->optdata[0] = TCP_OPT_MSS; |
| UIP_TCP_BUF(buf)->optdata[1] = TCP_OPT_MSS_LEN; |
| UIP_TCP_BUF(buf)->optdata[2] = (UIP_TCP_MSS) / 256; |
| UIP_TCP_BUF(buf)->optdata[3] = (UIP_TCP_MSS) & 255; |
| uip_len(buf) = UIP_IPTCPH_LEN + TCP_OPT_MSS_LEN; |
| UIP_TCP_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 wihtin our advertised window |
| before we accept the reset. */ |
| if(UIP_TCP_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 = (UIP_TCP_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) && |
| ((UIP_TCP_BUF(buf)->flags & TCP_CTL) == (TCP_SYN | TCP_ACK))) || |
| (((uip_connr->tcpstateflags & UIP_TS_MASK) == UIP_SYN_RCVD) && |
| ((UIP_TCP_BUF(buf)->flags & TCP_CTL) == TCP_SYN)))) { |
| if((uip_len(buf) > 0 || ((UIP_TCP_BUF(buf)->flags & (TCP_SYN | TCP_FIN)) != 0)) && |
| (UIP_TCP_BUF(buf)->seqno[0] != uip_connr->rcv_nxt[0] || |
| UIP_TCP_BUF(buf)->seqno[1] != uip_connr->rcv_nxt[1] || |
| UIP_TCP_BUF(buf)->seqno[2] != uip_connr->rcv_nxt[2] || |
| UIP_TCP_BUF(buf)->seqno[3] != uip_connr->rcv_nxt[3])) { |
| |
| if((UIP_TCP_BUF(buf)->flags & TCP_SYN)) { |
| if((uip_connr->tcpstateflags & UIP_TS_MASK) == UIP_SYN_RCVD) { |
| goto tcp_send_synack; |
| #if UIP_ACTIVE_OPEN |
| } else if((uip_connr->tcpstateflags & UIP_TS_MASK) == UIP_SYN_SENT) { |
| goto tcp_send_syn; |
| #endif |
| } |
| } |
| 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((UIP_TCP_BUF(buf)->flags & TCP_ACK) && uip_outstanding(uip_connr)) { |
| uip_add32(uip_connr->snd_nxt, uip_connr->len); |
| |
| if(UIP_TCP_BUF(buf)->ackno[0] == uip_acc32[0] && |
| UIP_TCP_BUF(buf)->ackno[1] == uip_acc32[1] && |
| UIP_TCP_BUF(buf)->ackno[2] == uip_acc32[2] && |
| UIP_TCP_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((UIP_TCP_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) && |
| (UIP_TCP_BUF(buf)->flags & TCP_CTL) == (TCP_SYN | TCP_ACK)) { |
| |
| /* Parse the TCP MSS option, if present. */ |
| if((UIP_TCP_BUF(buf)->tcpoffset & 0xf0) > 0x50) { |
| for(c = 0; c < ((UIP_TCP_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] = UIP_TCP_BUF(buf)->seqno[0]; |
| uip_connr->rcv_nxt[1] = UIP_TCP_BUF(buf)->seqno[1]; |
| uip_connr->rcv_nxt[2] = UIP_TCP_BUF(buf)->seqno[2]; |
| uip_connr->rcv_nxt[3] = UIP_TCP_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; |
| UIP_APPCALL(buf); |
| goto appsend; |
| } |
| /* 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(UIP_TCP_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: |
| UIP_TCP_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((UIP_TCP_BUF(buf)->flags & TCP_URG) != 0) { |
| #if UIP_URGDATA > 0 |
| uip_urglen = (UIP_TCP_BUF->urgp[0] << 8) | UIP_TCP_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)) + ((UIP_TCP_BUF(buf)->urgp[0] << 8) | UIP_TCP_BUF(buf)->urgp[1]); |
| uip_len(buf) -= (UIP_TCP_BUF(buf)->urgp[0] << 8) | UIP_TCP_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)UIP_TCP_BUF(buf)->wnd[0] << 8) + (uint16_t)UIP_TCP_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; |
| } |
| UIP_APPCALL(buf); |
| |
| appsend: |
| |
| if(uip_flags(buf) & UIP_ABORT) { |
| uip_slen(buf) = 0; |
| uip_connr->tcpstateflags = UIP_CLOSED; |
| UIP_TCP_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; |
| UIP_TCP_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); |
| } 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. */ |
| UIP_TCP_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; |
| UIP_TCP_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(UIP_TCP_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(UIP_TCP_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"); |
| UIP_TCP_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; |
| } |
| |
| tcp_send_noopts: |
| UIP_TCP_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"); |
| |
| UIP_TCP_BUF(buf)->ackno[0] = uip_connr->rcv_nxt[0]; |
| UIP_TCP_BUF(buf)->ackno[1] = uip_connr->rcv_nxt[1]; |
| UIP_TCP_BUF(buf)->ackno[2] = uip_connr->rcv_nxt[2]; |
| UIP_TCP_BUF(buf)->ackno[3] = uip_connr->rcv_nxt[3]; |
| |
| UIP_TCP_BUF(buf)->seqno[0] = uip_connr->snd_nxt[0]; |
| UIP_TCP_BUF(buf)->seqno[1] = uip_connr->snd_nxt[1]; |
| UIP_TCP_BUF(buf)->seqno[2] = uip_connr->snd_nxt[2]; |
| UIP_TCP_BUF(buf)->seqno[3] = uip_connr->snd_nxt[3]; |
| |
| UIP_TCP_BUF(buf)->srcport = uip_connr->lport; |
| UIP_TCP_BUF(buf)->destport = uip_connr->rport; |
| |
| uip_ipaddr_copy(&UIP_IP_BUF(buf)->destipaddr, &uip_connr->ripaddr); |
| uip_ds6_select_src(&UIP_IP_BUF(buf)->srcipaddr, &UIP_IP_BUF(buf)->destipaddr); |
| PRINTF("Sending TCP packet to "); |
| PRINT6ADDR(&UIP_IP_BUF(buf)->destipaddr); |
| PRINTF(" from "); |
| PRINT6ADDR(&UIP_IP_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. */ |
| UIP_TCP_BUF(buf)->wnd[0] = UIP_TCP_BUF(buf)->wnd[1] = 0; |
| } else { |
| UIP_TCP_BUF(buf)->wnd[0] = ((UIP_RECEIVE_WINDOW) >> 8); |
| UIP_TCP_BUF(buf)->wnd[1] = ((UIP_RECEIVE_WINDOW) & 0xff); |
| } |
| |
| tcp_send_noconn: |
| UIP_IP_BUF(buf)->proto = UIP_PROTO_TCP; |
| |
| UIP_IP_BUF(buf)->ttl = uip_ds6_if.cur_hop_limit; |
| UIP_IP_BUF(buf)->len[0] = ((uip_len(buf) - UIP_IPH_LEN) >> 8); |
| UIP_IP_BUF(buf)->len[1] = ((uip_len(buf) - UIP_IPH_LEN) & 0xff); |
| |
| UIP_TCP_BUF(buf)->urgp[0] = UIP_TCP_BUF(buf)->urgp[1] = 0; |
| |
| /* Calculate TCP checksum. */ |
| UIP_TCP_BUF(buf)->tcpchksum = 0; |
| UIP_TCP_BUF(buf)->tcpchksum = ~(uip_tcpchksum(buf)); |
| UIP_STAT(++uip_stat.tcp.sent); |
| |
| #endif /* UIP_TCP */ |
| #if UIP_UDP |
| ip_send_nolen: |
| #endif |
| UIP_IP_BUF(buf)->vtc = 0x60; |
| UIP_IP_BUF(buf)->tcflow = 0x00; |
| UIP_IP_BUF(buf)->flow = 0x00; |
| send: |
| PRINTF("Sending packet with length %d (%d)\n", uip_len(buf), |
| (UIP_IP_BUF(buf)->len[0] << 8) | UIP_IP_BUF(buf)->len[1]); |
| |
| UIP_STAT(++uip_stat.ip.sent); |
| /* Return and let the caller do the actual transmission. */ |
| uip_flags(buf) = 0; |
| buf->len = uip_len(buf); |
| return 1; |
| |
| drop: |
| uip_len(buf) = 0; |
| uip_ext_len(buf) = 0; |
| uip_ext_bitmap(buf) = 0; |
| uip_flags(buf) = 0; |
| 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_ipv6_output(buf); |
| if (!ret) { |
| PRINTF("Packet %p sending failed.\n", buf); |
| ip_buf_unref(buf); |
| } else { |
| ip_buf_sent_status(buf) = 0; |
| } |
| } |
| } |
| } |
| #endif /* UIP_TCP */ |
| /*---------------------------------------------------------------------------*/ |
| /** @} */ |