RealtimeCompLab2
Dependencies: mbed
Fork of PPP-Blinky by
main.cpp@13:d882b8a042b4, 2017-01-01 (annotated)
- Committer:
- nixnax
- Date:
- Sun Jan 01 02:09:18 2017 +0000
- Revision:
- 13:d882b8a042b4
- Parent:
- 12:db0dc91f0231
- Child:
- 14:c65831c25aaa
Output formatting
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
nixnax | 0:2cf4880c312a | 1 | #include "mbed.h" |
nixnax | 0:2cf4880c312a | 2 | |
nixnax | 12:db0dc91f0231 | 3 | // Copyright 2016 Nicolas Nackel. Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
nixnax | 12:db0dc91f0231 | 4 | |
nixnax | 0:2cf4880c312a | 5 | // Proof-of-concept for TCP/IP using Windows 7/8/10 Dial Up Networking over MBED USB Virtual COM Port |
nixnax | 0:2cf4880c312a | 6 | |
nixnax | 4:a469050d5b80 | 7 | // Toggles LED1 every time the PC sends an IP packet over the PPP link |
nixnax | 4:a469050d5b80 | 8 | |
nixnax | 4:a469050d5b80 | 9 | // Note - turn off all authentication, passwords, compression etc. Simplest link possible. |
nixnax | 0:2cf4880c312a | 10 | |
nixnax | 9:0992486d4a30 | 11 | // Handy links |
nixnax | 6:fba4c2e817b8 | 12 | // http://atari.kensclassics.org/wcomlog.htm |
nixnax | 6:fba4c2e817b8 | 13 | // https://technet.microsoft.com/en-us/library/cc957992.aspx |
nixnax | 6:fba4c2e817b8 | 14 | // http://www.sunshine2k.de/coding/javascript/crc/crc_js.html |
nixnax | 9:0992486d4a30 | 15 | // https://en.wikibooks.org/wiki/Serial_Programming/IP_Over_Serial_Connections |
nixnax | 6:fba4c2e817b8 | 16 | |
nixnax | 6:fba4c2e817b8 | 17 | Serial pc(USBTX, USBRX); // The USB com port - Set this up as a Dial-Up Modem on your pc |
nixnax | 4:a469050d5b80 | 18 | Serial xx(PC_10, PC_11); // debug port - use a second USB serial port to monitor |
nixnax | 0:2cf4880c312a | 19 | |
nixnax | 9:0992486d4a30 | 20 | #define debug(x) xx.printf( x ) |
nixnax | 9:0992486d4a30 | 21 | |
nixnax | 4:a469050d5b80 | 22 | DigitalOut led1(LED1); |
nixnax | 4:a469050d5b80 | 23 | |
nixnax | 4:a469050d5b80 | 24 | #define FRAME_7E (0x7e) |
nixnax | 13:d882b8a042b4 | 25 | #define BUFLEN (1<<13) |
nixnax | 4:a469050d5b80 | 26 | char rxbuf[BUFLEN]; |
nixnax | 4:a469050d5b80 | 27 | char frbuf[3000]; // buffer for ppp frame |
nixnax | 0:2cf4880c312a | 28 | |
nixnax | 4:a469050d5b80 | 29 | struct { |
nixnax | 4:a469050d5b80 | 30 | int online; |
nixnax | 4:a469050d5b80 | 31 | struct { |
nixnax | 4:a469050d5b80 | 32 | char * buf; |
nixnax | 4:a469050d5b80 | 33 | int head; |
nixnax | 4:a469050d5b80 | 34 | int tail; |
nixnax | 9:0992486d4a30 | 35 | int total; |
nixnax | 4:a469050d5b80 | 36 | } rx; // serial port buffer |
nixnax | 4:a469050d5b80 | 37 | struct { |
nixnax | 6:fba4c2e817b8 | 38 | int id; |
nixnax | 4:a469050d5b80 | 39 | int len; |
nixnax | 4:a469050d5b80 | 40 | int crc; |
nixnax | 4:a469050d5b80 | 41 | char * buf; |
nixnax | 4:a469050d5b80 | 42 | } pkt; // ppp buffer |
nixnax | 4:a469050d5b80 | 43 | } ppp; |
nixnax | 0:2cf4880c312a | 44 | |
nixnax | 9:0992486d4a30 | 45 | void pppInitStruct(){ ppp.online=0; ppp.rx.buf=rxbuf; ppp.rx.tail=0; ppp.rx.head=0; ppp.rx.total=0; ppp.pkt.buf=frbuf; ppp.pkt.len=0;} |
nixnax | 4:a469050d5b80 | 46 | |
nixnax | 4:a469050d5b80 | 47 | int crcG; // frame check sequence (CRC) holder |
nixnax | 4:a469050d5b80 | 48 | void crcDo(int x){for (int i=0;i<8;i++){crcG=((crcG&1)^(x&1))?(crcG>>1)^0x8408:crcG>>1;x>>=1;}} // crc calculator |
nixnax | 4:a469050d5b80 | 49 | void crcReset(){crcG=0xffff;} // crc restart |
nixnax | 9:0992486d4a30 | 50 | int crcBuf(char * buf, int size){crcReset();for(int i=0;i<size;i++)crcDo(*buf++);return crcG;} // crc on a block of memory |
nixnax | 0:2cf4880c312a | 51 | |
nixnax | 0:2cf4880c312a | 52 | void rxHandler() // serial port receive interrupt handler |
nixnax | 0:2cf4880c312a | 53 | { |
nixnax | 4:a469050d5b80 | 54 | ppp.rx.buf[ppp.rx.head]=pc.getc(); // insert in buffer |
nixnax | 0:2cf4880c312a | 55 | __disable_irq(); |
nixnax | 4:a469050d5b80 | 56 | ppp.rx.head=(ppp.rx.head+1)&(BUFLEN-1); |
nixnax | 9:0992486d4a30 | 57 | ppp.rx.total++; |
nixnax | 0:2cf4880c312a | 58 | __enable_irq(); |
nixnax | 0:2cf4880c312a | 59 | } |
nixnax | 0:2cf4880c312a | 60 | |
nixnax | 0:2cf4880c312a | 61 | int pc_readable() // check if buffer has data |
nixnax | 0:2cf4880c312a | 62 | { |
nixnax | 4:a469050d5b80 | 63 | return (ppp.rx.head==ppp.rx.tail) ? 0 : 1 ; |
nixnax | 0:2cf4880c312a | 64 | } |
nixnax | 0:2cf4880c312a | 65 | |
nixnax | 0:2cf4880c312a | 66 | int pc_getBuf() // get one character from the buffer |
nixnax | 0:2cf4880c312a | 67 | { |
nixnax | 0:2cf4880c312a | 68 | if (pc_readable()) { |
nixnax | 4:a469050d5b80 | 69 | int x = ppp.rx.buf[ ppp.rx.tail ]; |
nixnax | 4:a469050d5b80 | 70 | ppp.rx.tail=(ppp.rx.tail+1)&(BUFLEN-1); |
nixnax | 0:2cf4880c312a | 71 | return x; |
nixnax | 0:2cf4880c312a | 72 | } |
nixnax | 0:2cf4880c312a | 73 | return -1; |
nixnax | 0:2cf4880c312a | 74 | } |
nixnax | 0:2cf4880c312a | 75 | |
nixnax | 4:a469050d5b80 | 76 | void scanForConnectString(); // scan for connect attempts from pc |
nixnax | 1:9e03798d4367 | 77 | |
nixnax | 9:0992486d4a30 | 78 | void processFrame(int start, int end) { // process received frame |
nixnax | 9:0992486d4a30 | 79 | if(start==end) { xx.printf("Null Frame c=%d\n",ppp.rx.total); pc.putc(0x7e); return; } |
nixnax | 9:0992486d4a30 | 80 | crcReset(); |
nixnax | 9:0992486d4a30 | 81 | char * dest = ppp.pkt.buf; |
nixnax | 9:0992486d4a30 | 82 | ppp.pkt.len=0; |
nixnax | 9:0992486d4a30 | 83 | int unstuff=0; |
nixnax | 9:0992486d4a30 | 84 | for (int i=start; i<end; i++) { |
nixnax | 9:0992486d4a30 | 85 | if (unstuff==0) { |
nixnax | 9:0992486d4a30 | 86 | if (rxbuf[i]==0x7d) unstuff=1; |
nixnax | 9:0992486d4a30 | 87 | else { *dest++ = rxbuf[i]; ppp.pkt.len++; crcDo(rxbuf[i]);} |
nixnax | 12:db0dc91f0231 | 88 | } else { // unstuff |
nixnax | 9:0992486d4a30 | 89 | *dest++ = rxbuf[i]^0x20; ppp.pkt.len++; crcDo((int)rxbuf[i]^0x20); |
nixnax | 9:0992486d4a30 | 90 | unstuff=0; |
nixnax | 9:0992486d4a30 | 91 | } |
nixnax | 9:0992486d4a30 | 92 | } |
nixnax | 9:0992486d4a30 | 93 | ppp.pkt.crc = crcG & 0xffff; |
nixnax | 9:0992486d4a30 | 94 | if (ppp.pkt.crc == 0xf0b8) { // check for good CRC |
nixnax | 9:0992486d4a30 | 95 | void determinePacketType(); // declare early |
nixnax | 9:0992486d4a30 | 96 | determinePacketType(); |
nixnax | 12:db0dc91f0231 | 97 | } else { // crc error |
nixnax | 12:db0dc91f0231 | 98 | xx.printf("CRC is %x Len is %d\n",ppp.pkt.crc,ppp.pkt.len); |
nixnax | 9:0992486d4a30 | 99 | for(int i=0;i<ppp.pkt.len;i++)xx.printf("%02x ", ppp.pkt.buf[i]); |
nixnax | 12:db0dc91f0231 | 100 | xx.printf("\n"); |
nixnax | 9:0992486d4a30 | 101 | } |
nixnax | 9:0992486d4a30 | 102 | } |
nixnax | 9:0992486d4a30 | 103 | |
nixnax | 11:f58998c24f0b | 104 | void dumpFrame() { |
nixnax | 11:f58998c24f0b | 105 | for(int i=0;i<ppp.pkt.len/2;i++) xx.printf("%02x ", ppp.pkt.buf[i]); |
nixnax | 11:f58998c24f0b | 106 | xx.printf(" C %02x %02x L=%d\n", ppp.pkt.crc&0xff, (ppp.pkt.crc>>8)&0xff, ppp.pkt.len); |
nixnax | 11:f58998c24f0b | 107 | } |
nixnax | 9:0992486d4a30 | 108 | |
nixnax | 9:0992486d4a30 | 109 | void sendFrame(){ |
nixnax | 9:0992486d4a30 | 110 | int crc = crcBuf(ppp.pkt.buf, ppp.pkt.len-2); // get crc |
nixnax | 12:db0dc91f0231 | 111 | ppp.pkt.buf[ ppp.pkt.len-2 ] = (~crc>>0); // fcs lo (crc) |
nixnax | 12:db0dc91f0231 | 112 | ppp.pkt.buf[ ppp.pkt.len-1 ] = (~crc>>8); // fcs hi (crc) |
nixnax | 12:db0dc91f0231 | 113 | pc.putc(0x7e); // frame start flag |
nixnax | 9:0992486d4a30 | 114 | for(int i=0;i<ppp.pkt.len;i++) { |
nixnax | 11:f58998c24f0b | 115 | //xx.printf( "%2x ", ppp.pkt.buf[i]); |
nixnax | 9:0992486d4a30 | 116 | unsigned int cc = (unsigned int)ppp.pkt.buf[i]; |
nixnax | 9:0992486d4a30 | 117 | if (cc>32) pc.putc(cc); else {pc.putc(0x7d); pc.putc(cc+32);} |
nixnax | 9:0992486d4a30 | 118 | } |
nixnax | 12:db0dc91f0231 | 119 | pc.putc(0x7e); // frame end flag |
nixnax | 9:0992486d4a30 | 120 | } |
nixnax | 9:0992486d4a30 | 121 | |
nixnax | 9:0992486d4a30 | 122 | void ipRequestHandler(){ |
nixnax | 9:0992486d4a30 | 123 | debug("IPCP Conf "); |
nixnax | 9:0992486d4a30 | 124 | if ( ppp.pkt.buf[7] != 4 ) { |
nixnax | 9:0992486d4a30 | 125 | debug("Rej\n"); // reject if any options are requested |
nixnax | 9:0992486d4a30 | 126 | ppp.pkt.buf[4]=4; |
nixnax | 9:0992486d4a30 | 127 | sendFrame(); |
nixnax | 9:0992486d4a30 | 128 | } else { |
nixnax | 9:0992486d4a30 | 129 | debug("Ack\n"); |
nixnax | 9:0992486d4a30 | 130 | ppp.pkt.buf[4]=2; // ack the minimum |
nixnax | 9:0992486d4a30 | 131 | sendFrame(); // acknowledge |
nixnax | 12:db0dc91f0231 | 132 | debug("IPCP Ask\n"); |
nixnax | 9:0992486d4a30 | 133 | // send our own request now |
nixnax | 12:db0dc91f0231 | 134 | ppp.pkt.buf[4]=1; // request no options |
nixnax | 9:0992486d4a30 | 135 | ppp.pkt.buf[5]++; // next sequence |
nixnax | 9:0992486d4a30 | 136 | sendFrame(); // this is our request |
nixnax | 9:0992486d4a30 | 137 | } |
nixnax | 9:0992486d4a30 | 138 | } |
nixnax | 9:0992486d4a30 | 139 | |
nixnax | 9:0992486d4a30 | 140 | void ipAckHandler(){ debug("IPCP Grant\n"); } |
nixnax | 9:0992486d4a30 | 141 | |
nixnax | 9:0992486d4a30 | 142 | void ipNackHandler(){ debug("IPCP Nack\n"); } |
nixnax | 9:0992486d4a30 | 143 | |
nixnax | 9:0992486d4a30 | 144 | void ipDefaultHandler(){ debug("IPCP Other\n"); } |
nixnax | 9:0992486d4a30 | 145 | |
nixnax | 9:0992486d4a30 | 146 | void IPCPframe() { |
nixnax | 9:0992486d4a30 | 147 | led1 = ppp.pkt.buf[5] & 1; // This is the sequence number so the led blinks on packets |
nixnax | 9:0992486d4a30 | 148 | //ppp.pkt.id = ppp.pkt.buf[5]; // remember the sequence number |
nixnax | 9:0992486d4a30 | 149 | int code = ppp.pkt.buf[4]; // packet type is here |
nixnax | 9:0992486d4a30 | 150 | switch (code) { |
nixnax | 9:0992486d4a30 | 151 | case 1: ipRequestHandler(); break; |
nixnax | 9:0992486d4a30 | 152 | case 2: ipAckHandler(); break; |
nixnax | 9:0992486d4a30 | 153 | case 3: ipNackHandler(); break; |
nixnax | 9:0992486d4a30 | 154 | default: ipDefaultHandler(); |
nixnax | 9:0992486d4a30 | 155 | } |
nixnax | 9:0992486d4a30 | 156 | } |
nixnax | 9:0992486d4a30 | 157 | |
nixnax | 10:74f8233f72c0 | 158 | void UDPpacket() { |
nixnax | 12:db0dc91f0231 | 159 | char * udpPkt = ppp.pkt.buf+4; // udp packet start |
nixnax | 12:db0dc91f0231 | 160 | //char * pktLen = udpPkt+2; // total packet length |
nixnax | 12:db0dc91f0231 | 161 | int headerSize = (( udpPkt[0]&0xf)*4); |
nixnax | 12:db0dc91f0231 | 162 | char * udpBlock = udpPkt + headerSize; // udp info start |
nixnax | 12:db0dc91f0231 | 163 | char * udpSrc = udpBlock; // source port |
nixnax | 12:db0dc91f0231 | 164 | char * udpDst = udpBlock+2; // destination port |
nixnax | 12:db0dc91f0231 | 165 | char * udpLen = udpBlock+4; // udp data length |
nixnax | 12:db0dc91f0231 | 166 | char * udpInf = udpBlock+8; // actual start of info |
nixnax | 12:db0dc91f0231 | 167 | //char * udpSum = udpBlock+6; // udp checksum |
nixnax | 12:db0dc91f0231 | 168 | //int packetLength = (pktLen[0]<<8) | pktLen[1]; // udp total packet length |
nixnax | 12:db0dc91f0231 | 169 | int srcPort = (udpSrc[0]<<8) | udpSrc[1]; |
nixnax | 12:db0dc91f0231 | 170 | int dstPort = (udpDst[0]<<8) | udpDst[1]; |
nixnax | 12:db0dc91f0231 | 171 | char * srcIP = udpPkt+12; // udp src addr |
nixnax | 12:db0dc91f0231 | 172 | char * dstIP = udpPkt+16; // udp dst addr |
nixnax | 12:db0dc91f0231 | 173 | #define UDP_HEADER_SIZE 8 |
nixnax | 12:db0dc91f0231 | 174 | int udpLength = ((udpLen[0]<<8) | udpLen[1]) - UDP_HEADER_SIZE; // size of the actual udp data |
nixnax | 12:db0dc91f0231 | 175 | xx.printf("UDP %d.%d.%d.%d:%d ", srcIP[0],srcIP[1],srcIP[2],srcIP[3],srcPort); |
nixnax | 12:db0dc91f0231 | 176 | xx.printf("%d.%d.%d.%d:%d ", dstIP[1],dstIP[1],dstIP[1],dstIP[1],dstPort); |
nixnax | 12:db0dc91f0231 | 177 | xx.printf("Len %d ", udpLength); |
nixnax | 13:d882b8a042b4 | 178 | int printSize = udpLength; if (printSize > 20) printSize = 20; // print only first 20 characters |
nixnax | 13:d882b8a042b4 | 179 | for (int i=0; i<printSize; i++) { char ch = udpInf[i]; if (ch>31 && ch<127) xx.putc(ch); else xx.putc('?'); } |
nixnax | 12:db0dc91f0231 | 180 | xx.printf("\n"); |
nixnax | 12:db0dc91f0231 | 181 | } |
nixnax | 11:f58998c24f0b | 182 | |
nixnax | 11:f58998c24f0b | 183 | int dataCheckSum(char * ptr, int len) { |
nixnax | 11:f58998c24f0b | 184 | int sum=0; |
nixnax | 11:f58998c24f0b | 185 | for (int i=0;i<len/2;i++) { |
nixnax | 11:f58998c24f0b | 186 | int hi = *ptr; ptr++; |
nixnax | 11:f58998c24f0b | 187 | int lo = *ptr; ptr++; |
nixnax | 11:f58998c24f0b | 188 | int val = ( lo & 0xff ) | ( (hi<<8) & 0xff00 ); |
nixnax | 11:f58998c24f0b | 189 | sum = sum + val; |
nixnax | 11:f58998c24f0b | 190 | } |
nixnax | 11:f58998c24f0b | 191 | sum = sum + (sum>>16); |
nixnax | 12:db0dc91f0231 | 192 | return ~sum; |
nixnax | 11:f58998c24f0b | 193 | } |
nixnax | 11:f58998c24f0b | 194 | |
nixnax | 11:f58998c24f0b | 195 | void headerCheckSum() { |
nixnax | 11:f58998c24f0b | 196 | int len =(ppp.pkt.buf[4]&0xf)*4; // length of header in bytes |
nixnax | 11:f58998c24f0b | 197 | char * ptr = ppp.pkt.buf+4; // start of ip packet |
nixnax | 11:f58998c24f0b | 198 | int sum=0; |
nixnax | 11:f58998c24f0b | 199 | |
nixnax | 11:f58998c24f0b | 200 | for (int i=0;i<len/2;i++) { |
nixnax | 11:f58998c24f0b | 201 | int hi = *ptr; ptr++; |
nixnax | 11:f58998c24f0b | 202 | int lo = *ptr; ptr++; |
nixnax | 11:f58998c24f0b | 203 | int val = ( lo & 0xff ) | ( (hi<<8) & 0xff00 ); |
nixnax | 11:f58998c24f0b | 204 | sum = sum + val; |
nixnax | 11:f58998c24f0b | 205 | } |
nixnax | 11:f58998c24f0b | 206 | sum = sum + (sum>>16); |
nixnax | 11:f58998c24f0b | 207 | sum = ~sum; |
nixnax | 11:f58998c24f0b | 208 | ppp.pkt.buf[14]= (sum>>8); |
nixnax | 11:f58998c24f0b | 209 | ppp.pkt.buf[15]= (sum ); |
nixnax | 9:0992486d4a30 | 210 | } |
nixnax | 9:0992486d4a30 | 211 | |
nixnax | 11:f58998c24f0b | 212 | void ICMPpacket() { // internet control message protocol |
nixnax | 12:db0dc91f0231 | 213 | char * ipPkt = ppp.pkt.buf+4; // ip packet start |
nixnax | 12:db0dc91f0231 | 214 | char * pktLen = ipPkt+2; |
nixnax | 12:db0dc91f0231 | 215 | int packetLength = (pktLen[0]<<8) | pktLen[1]; // icmp packet length |
nixnax | 12:db0dc91f0231 | 216 | int headerSize = (( ipPkt[0]&0xf)*4); |
nixnax | 12:db0dc91f0231 | 217 | char * icmpType = ipPkt + headerSize; // icmp data start |
nixnax | 13:d882b8a042b4 | 218 | char * icmpSum = icmpType+2; // icmp checksum |
nixnax | 13:d882b8a042b4 | 219 | |
nixnax | 12:db0dc91f0231 | 220 | #define ICMP_TYPE_PING_REQUEST 8 |
nixnax | 12:db0dc91f0231 | 221 | if ( icmpType[0] == ICMP_TYPE_PING_REQUEST ) { |
nixnax | 12:db0dc91f0231 | 222 | char * ipTTL = ipPkt+8; // time to live |
nixnax | 12:db0dc91f0231 | 223 | ipTTL[0]--; // decrement time to live |
nixnax | 12:db0dc91f0231 | 224 | char * srcAdr = ipPkt+12; |
nixnax | 12:db0dc91f0231 | 225 | char * dstAdr = ipPkt+16; |
nixnax | 13:d882b8a042b4 | 226 | xx.printf("ICMP PING %d.%d.%d.%d %d.%d.%d.%d ", srcAdr[0],srcAdr[1],srcAdr[2],srcAdr[3],dstAdr[0],dstAdr[1],dstAdr[2],dstAdr[3]); |
nixnax | 11:f58998c24f0b | 227 | char src[4]; char dst[4]; |
nixnax | 12:db0dc91f0231 | 228 | memcpy(src, srcAdr,4); |
nixnax | 12:db0dc91f0231 | 229 | memcpy(dst, dstAdr,4); |
nixnax | 12:db0dc91f0231 | 230 | memcpy(srcAdr, dst,4); |
nixnax | 12:db0dc91f0231 | 231 | memcpy(dstAdr, src,4); // swap src & dest ip |
nixnax | 12:db0dc91f0231 | 232 | char * chkSum = ipPkt+10; |
nixnax | 12:db0dc91f0231 | 233 | chkSum[0]=0; chkSum[1]=0; |
nixnax | 12:db0dc91f0231 | 234 | headerCheckSum(); // new ip header checksum |
nixnax | 12:db0dc91f0231 | 235 | #define ICMP_TYPE_ECHO_REPLY 0 |
nixnax | 12:db0dc91f0231 | 236 | icmpType[0]=ICMP_TYPE_ECHO_REPLY; // icmp echo replay |
nixnax | 12:db0dc91f0231 | 237 | icmpSum[0]=0; icmpSum[1]=0; // zero the checksum for recalculation |
nixnax | 12:db0dc91f0231 | 238 | int dataLength = packetLength - headerSize; // length of ICMP data portion |
nixnax | 13:d882b8a042b4 | 239 | int sum = dataCheckSum( icmpType, dataLength); // this checksum on icmp data portion |
nixnax | 12:db0dc91f0231 | 240 | icmpSum[0]=sum>>8; icmpSum[1]=sum; // new checksum for ICMP data portion |
nixnax | 13:d882b8a042b4 | 241 | sendFrame(); // reply to the ping |
nixnax | 13:d882b8a042b4 | 242 | |
nixnax | 13:d882b8a042b4 | 243 | int printSize = dataLength-8; // exclude size of icmp header |
nixnax | 13:d882b8a042b4 | 244 | char * icmpData = icmpType+8; // the actual data is after the header |
nixnax | 13:d882b8a042b4 | 245 | if (printSize > 20) printSize = 20; // print only first 20 characters |
nixnax | 13:d882b8a042b4 | 246 | for (int i=0; i<printSize; i++) { char ch = icmpData[i]; if (ch>31 && ch<127) xx.putc(ch); else xx.putc('?'); } |
nixnax | 13:d882b8a042b4 | 247 | xx.putc('\n'); |
nixnax | 12:db0dc91f0231 | 248 | } else { |
nixnax | 12:db0dc91f0231 | 249 | xx.printf("ICMP type=%d \n", icmpType[0]); |
nixnax | 11:f58998c24f0b | 250 | } |
nixnax | 11:f58998c24f0b | 251 | } |
nixnax | 11:f58998c24f0b | 252 | |
nixnax | 11:f58998c24f0b | 253 | void IGMPpacket() { // internet group management protocol |
nixnax | 11:f58998c24f0b | 254 | xx.printf("IGMP type=%d \n", ppp.pkt.buf[28]); |
nixnax | 11:f58998c24f0b | 255 | } |
nixnax | 11:f58998c24f0b | 256 | |
nixnax | 11:f58998c24f0b | 257 | void TCPpacket() { |
nixnax | 11:f58998c24f0b | 258 | debug("TCP\n"); |
nixnax | 10:74f8233f72c0 | 259 | /* |
nixnax | 11:f58998c24f0b | 260 | switch (protocol) { |
nixnax | 11:f58998c24f0b | 261 | case 2: TCPsyn(); break; |
nixnax | 11:f58998c24f0b | 262 | case 17: TCPack(); break; |
nixnax | 11:f58998c24f0b | 263 | case 6: TCPpacket(); break; |
nixnax | 11:f58998c24f0b | 264 | default: debug( "Other \n"); |
nixnax | 11:f58998c24f0b | 265 | } |
nixnax | 10:74f8233f72c0 | 266 | */ |
nixnax | 10:74f8233f72c0 | 267 | } |
nixnax | 10:74f8233f72c0 | 268 | |
nixnax | 11:f58998c24f0b | 269 | void otherProtocol() { |
nixnax | 12:db0dc91f0231 | 270 | debug("Other IP protocol"); |
nixnax | 11:f58998c24f0b | 271 | } |
nixnax | 11:f58998c24f0b | 272 | |
nixnax | 10:74f8233f72c0 | 273 | void IPframe() { |
nixnax | 10:74f8233f72c0 | 274 | int protocol = ppp.pkt.buf[13]; |
nixnax | 10:74f8233f72c0 | 275 | switch (protocol) { |
nixnax | 11:f58998c24f0b | 276 | case 1: ICMPpacket(); break; |
nixnax | 11:f58998c24f0b | 277 | case 2: IGMPpacket(); break; |
nixnax | 11:f58998c24f0b | 278 | case 17: UDPpacket(); break; |
nixnax | 11:f58998c24f0b | 279 | case 6: TCPpacket(); break; |
nixnax | 11:f58998c24f0b | 280 | default: otherProtocol(); |
nixnax | 10:74f8233f72c0 | 281 | } |
nixnax | 10:74f8233f72c0 | 282 | //xx.printf("IP frame proto %3d len %4d %d.%d.%d.%d %d.%d.%d.%d\n", ppp.pkt.buf[13],(ppp.pkt.buf[6]<<8)+ppp.pkt.buf[7],ppp.pkt.buf[16],ppp.pkt.buf[17],ppp.pkt.buf[18],ppp.pkt.buf[19],ppp.pkt.buf[20],ppp.pkt.buf[21],ppp.pkt.buf[22],ppp.pkt.buf[23] ); |
nixnax | 10:74f8233f72c0 | 283 | } |
nixnax | 9:0992486d4a30 | 284 | |
nixnax | 9:0992486d4a30 | 285 | void LCPconfReq() { |
nixnax | 11:f58998c24f0b | 286 | debug("LCP Config "); |
nixnax | 9:0992486d4a30 | 287 | if (ppp.pkt.buf[7] != 4) { |
nixnax | 11:f58998c24f0b | 288 | ppp.pkt.buf[4]=4; // allow only no options |
nixnax | 11:f58998c24f0b | 289 | debug("Reject\n"); |
nixnax | 9:0992486d4a30 | 290 | sendFrame(); |
nixnax | 9:0992486d4a30 | 291 | } else { |
nixnax | 9:0992486d4a30 | 292 | ppp.pkt.buf[4]=2; // ack zero conf |
nixnax | 9:0992486d4a30 | 293 | debug("Ack\n"); |
nixnax | 9:0992486d4a30 | 294 | sendFrame(); |
nixnax | 10:74f8233f72c0 | 295 | debug("LCP Ask\n"); |
nixnax | 11:f58998c24f0b | 296 | ppp.pkt.buf[4]=1; // request no options |
nixnax | 9:0992486d4a30 | 297 | sendFrame(); |
nixnax | 9:0992486d4a30 | 298 | } |
nixnax | 9:0992486d4a30 | 299 | } |
nixnax | 9:0992486d4a30 | 300 | |
nixnax | 9:0992486d4a30 | 301 | void LCPconfAck() { |
nixnax | 9:0992486d4a30 | 302 | debug("LCP Ack\n"); |
nixnax | 9:0992486d4a30 | 303 | } |
nixnax | 9:0992486d4a30 | 304 | |
nixnax | 9:0992486d4a30 | 305 | void LCPend(){ |
nixnax | 9:0992486d4a30 | 306 | debug("LCP End\n"); |
nixnax | 12:db0dc91f0231 | 307 | ppp.online=0; // start hunting for connect string again |
nixnax | 9:0992486d4a30 | 308 | ppp.pkt.buf[4]=6; |
nixnax | 12:db0dc91f0231 | 309 | sendFrame(); // acknowledge |
nixnax | 9:0992486d4a30 | 310 | } |
nixnax | 9:0992486d4a30 | 311 | |
nixnax | 9:0992486d4a30 | 312 | void LCPother(){ |
nixnax | 9:0992486d4a30 | 313 | debug("LCP Other\n"); |
nixnax | 12:db0dc91f0231 | 314 | dumpFrame(); |
nixnax | 9:0992486d4a30 | 315 | } |
nixnax | 9:0992486d4a30 | 316 | |
nixnax | 9:0992486d4a30 | 317 | void LCPframe(){ |
nixnax | 9:0992486d4a30 | 318 | int code = ppp.pkt.buf[4]; |
nixnax | 9:0992486d4a30 | 319 | switch (code) { |
nixnax | 12:db0dc91f0231 | 320 | case 1: LCPconfReq(); break; // config request |
nixnax | 12:db0dc91f0231 | 321 | case 2: LCPconfAck(); break; // config ack |
nixnax | 12:db0dc91f0231 | 322 | case 5: LCPend(); break; // end connection |
nixnax | 12:db0dc91f0231 | 323 | default: LCPother(); |
nixnax | 9:0992486d4a30 | 324 | } |
nixnax | 9:0992486d4a30 | 325 | } |
nixnax | 9:0992486d4a30 | 326 | |
nixnax | 12:db0dc91f0231 | 327 | void discardedFrame() { |
nixnax | 12:db0dc91f0231 | 328 | xx.printf("Dropping frame %02x %02x %02x %02x\n", ppp.pkt.buf[0],ppp.pkt.buf[1],ppp.pkt.buf[2],ppp.pkt.buf[3] ); |
nixnax | 9:0992486d4a30 | 329 | } |
nixnax | 9:0992486d4a30 | 330 | |
nixnax | 9:0992486d4a30 | 331 | void determinePacketType() { |
nixnax | 9:0992486d4a30 | 332 | if ( ppp.pkt.buf[0] != 0xff ) {debug("byte0 != ff\n"); return;} |
nixnax | 9:0992486d4a30 | 333 | if ( ppp.pkt.buf[1] != 3 ) {debug("byte1 != 3\n"); return;} |
nixnax | 9:0992486d4a30 | 334 | if ( ppp.pkt.buf[3] != 0x21 ) {debug("byte2 != 21\n"); return;} |
nixnax | 9:0992486d4a30 | 335 | int packetType = ppp.pkt.buf[2]; |
nixnax | 9:0992486d4a30 | 336 | switch (packetType) { |
nixnax | 12:db0dc91f0231 | 337 | case 0xc0: LCPframe(); break; // link control |
nixnax | 12:db0dc91f0231 | 338 | case 0x80: IPCPframe(); break; // IP control |
nixnax | 12:db0dc91f0231 | 339 | case 0x00: IPframe(); break; // IP itself |
nixnax | 12:db0dc91f0231 | 340 | default: discardedFrame(); |
nixnax | 9:0992486d4a30 | 341 | } |
nixnax | 9:0992486d4a30 | 342 | } |
nixnax | 9:0992486d4a30 | 343 | |
nixnax | 9:0992486d4a30 | 344 | void scanForConnectString() { |
nixnax | 9:0992486d4a30 | 345 | if ( ppp.online==0 ) { |
nixnax | 9:0992486d4a30 | 346 | char * clientFound = strstr( rxbuf, "CLIENTCLIENT" ); // look for PC string |
nixnax | 9:0992486d4a30 | 347 | if( clientFound ) { |
nixnax | 9:0992486d4a30 | 348 | strcpy( clientFound, "FOUND!FOUND!" ); // overwrite so we don't get fixated |
nixnax | 9:0992486d4a30 | 349 | pc.printf("CLIENTSERVER"); // respond to PC |
nixnax | 9:0992486d4a30 | 350 | ppp.online=1; // we can stop looking for the string |
nixnax | 9:0992486d4a30 | 351 | debug("Connect string found\n"); |
nixnax | 9:0992486d4a30 | 352 | } |
nixnax | 9:0992486d4a30 | 353 | } |
nixnax | 9:0992486d4a30 | 354 | } |
nixnax | 9:0992486d4a30 | 355 | |
nixnax | 0:2cf4880c312a | 356 | int main() |
nixnax | 0:2cf4880c312a | 357 | { |
nixnax | 12:db0dc91f0231 | 358 | pc.baud(115200); |
nixnax | 4:a469050d5b80 | 359 | xx.baud(115200); |
nixnax | 9:0992486d4a30 | 360 | xx.puts("\x1b[2J\x1b[HReady\n"); // VT100 code for clear screen & home |
nixnax | 4:a469050d5b80 | 361 | |
nixnax | 9:0992486d4a30 | 362 | pppInitStruct(); // initialize all the PPP properties |
nixnax | 4:a469050d5b80 | 363 | |
nixnax | 9:0992486d4a30 | 364 | pc.attach(&rxHandler,Serial::RxIrq); // start the receive handler |
nixnax | 4:a469050d5b80 | 365 | |
nixnax | 9:0992486d4a30 | 366 | int frameStartIndex, frameEndIndex; int frameBusy=0; |
nixnax | 4:a469050d5b80 | 367 | |
nixnax | 0:2cf4880c312a | 368 | while(1) { |
nixnax | 9:0992486d4a30 | 369 | if ( ppp.online==0 ) scanForConnectString(); // try to connect |
nixnax | 0:2cf4880c312a | 370 | while ( pc_readable() ) { |
nixnax | 1:9e03798d4367 | 371 | int rx = pc_getBuf(); |
nixnax | 9:0992486d4a30 | 372 | wait(0.001); |
nixnax | 4:a469050d5b80 | 373 | if (frameBusy) { |
nixnax | 4:a469050d5b80 | 374 | if (rx==FRAME_7E) { |
nixnax | 4:a469050d5b80 | 375 | frameBusy=0; // done gathering frame |
nixnax | 4:a469050d5b80 | 376 | frameEndIndex=ppp.rx.tail-1; // remember where frame ends |
nixnax | 4:a469050d5b80 | 377 | void processFrame(int start, int end); // process a received frame |
nixnax | 4:a469050d5b80 | 378 | processFrame(frameStartIndex, frameEndIndex); |
nixnax | 4:a469050d5b80 | 379 | } |
nixnax | 4:a469050d5b80 | 380 | } |
nixnax | 4:a469050d5b80 | 381 | else { |
nixnax | 4:a469050d5b80 | 382 | if (rx==FRAME_7E) { |
nixnax | 4:a469050d5b80 | 383 | frameBusy=1; // start gathering frame |
nixnax | 9:0992486d4a30 | 384 | frameStartIndex=ppp.rx.tail; // remember where frame started |
nixnax | 4:a469050d5b80 | 385 | } |
nixnax | 0:2cf4880c312a | 386 | } |
nixnax | 4:a469050d5b80 | 387 | } |
nixnax | 7:ab147f5e97ac | 388 | } |
nixnax | 7:ab147f5e97ac | 389 | } |