RealtimeCompLab2
Dependencies: mbed
Fork of PPP-Blinky by
main.cpp@28:1aa629be05e7, 2017-01-04 (annotated)
- Committer:
- nixnax
- Date:
- Wed Jan 04 02:20:06 2017 +0000
- Revision:
- 28:1aa629be05e7
- Parent:
- 27:78d194dd8799
- Child:
- 29:30de79d658f6
HTTP, UDP and PING now working
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 | 19:e53cdee9a33c | 12 | // https://developer.mbed.org/users/nixnax/code/PPP-Blinky/ - introduction and notes |
nixnax | 6:fba4c2e817b8 | 13 | // http://atari.kensclassics.org/wcomlog.htm |
nixnax | 6:fba4c2e817b8 | 14 | // https://technet.microsoft.com/en-us/library/cc957992.aspx |
nixnax | 6:fba4c2e817b8 | 15 | // http://www.sunshine2k.de/coding/javascript/crc/crc_js.html |
nixnax | 9:0992486d4a30 | 16 | // https://en.wikibooks.org/wiki/Serial_Programming/IP_Over_Serial_Connections |
nixnax | 19:e53cdee9a33c | 17 | // http://pingtester.net/ - nice tool for high rate ping testing |
nixnax | 6:fba4c2e817b8 | 18 | |
nixnax | 28:1aa629be05e7 | 19 | Serial xx(USBTX, USBRX); // The USB com port - Set this up as a Dial-Up Modem on your pc |
nixnax | 28:1aa629be05e7 | 20 | Serial pc(PC_10, PC_11); // debug((((( port - use an additional USB serial port to monitor this |
nixnax | 0:2cf4880c312a | 21 | |
nixnax | 19:e53cdee9a33c | 22 | // the second #define below gets rid of all the debug printfs |
nixnax | 20:5db9b77b38a6 | 23 | #define debug(x) xx.printf x |
nixnax | 19:e53cdee9a33c | 24 | //#define debug(x) {} |
nixnax | 9:0992486d4a30 | 25 | |
nixnax | 4:a469050d5b80 | 26 | DigitalOut led1(LED1); |
nixnax | 4:a469050d5b80 | 27 | |
nixnax | 4:a469050d5b80 | 28 | #define FRAME_7E (0x7e) |
nixnax | 19:e53cdee9a33c | 29 | #define BUFLEN (1<<14) |
nixnax | 20:5db9b77b38a6 | 30 | char rxbuf[BUFLEN]; |
nixnax | 17:4918c893d802 | 31 | char frbuf[6000]; // buffer for ppp frame |
nixnax | 0:2cf4880c312a | 32 | |
nixnax | 4:a469050d5b80 | 33 | struct { |
nixnax | 4:a469050d5b80 | 34 | int online; |
nixnax | 26:11f4eb2663a7 | 35 | int ident; |
nixnax | 28:1aa629be05e7 | 36 | int sync; |
nixnax | 28:1aa629be05e7 | 37 | int seq; |
nixnax | 4:a469050d5b80 | 38 | struct { |
nixnax | 20:5db9b77b38a6 | 39 | char * buf; |
nixnax | 15:b0154c910143 | 40 | volatile int head; |
nixnax | 20:5db9b77b38a6 | 41 | volatile int tail; |
nixnax | 9:0992486d4a30 | 42 | int total; |
nixnax | 4:a469050d5b80 | 43 | } rx; // serial port buffer |
nixnax | 4:a469050d5b80 | 44 | struct { |
nixnax | 6:fba4c2e817b8 | 45 | int id; |
nixnax | 4:a469050d5b80 | 46 | int len; |
nixnax | 4:a469050d5b80 | 47 | int crc; |
nixnax | 4:a469050d5b80 | 48 | char * buf; |
nixnax | 4:a469050d5b80 | 49 | } pkt; // ppp buffer |
nixnax | 4:a469050d5b80 | 50 | } ppp; |
nixnax | 0:2cf4880c312a | 51 | |
nixnax | 26:11f4eb2663a7 | 52 | struct tcpType { |
nixnax | 26:11f4eb2663a7 | 53 | int connect; |
nixnax | 26:11f4eb2663a7 | 54 | int ack; |
nixnax | 26:11f4eb2663a7 | 55 | int seq; |
nixnax | 26:11f4eb2663a7 | 56 | }; |
nixnax | 26:11f4eb2663a7 | 57 | |
nixnax | 26:11f4eb2663a7 | 58 | tcpType tcp; |
nixnax | 26:11f4eb2663a7 | 59 | |
nixnax | 26:11f4eb2663a7 | 60 | |
nixnax | 28:1aa629be05e7 | 61 | 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; ppp.ident=0; ppp.sync=0; ppp.seq=77;} |
nixnax | 4:a469050d5b80 | 62 | |
nixnax | 4:a469050d5b80 | 63 | int crcG; // frame check sequence (CRC) holder |
nixnax | 4:a469050d5b80 | 64 | 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 | 65 | void crcReset(){crcG=0xffff;} // crc restart |
nixnax | 9:0992486d4a30 | 66 | 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 | 67 | |
nixnax | 0:2cf4880c312a | 68 | void rxHandler() // serial port receive interrupt handler |
nixnax | 0:2cf4880c312a | 69 | { |
nixnax | 17:4918c893d802 | 70 | while ( pc.readable() ) { |
nixnax | 20:5db9b77b38a6 | 71 | int hd = (ppp.rx.head+1)&(BUFLEN-1); // increment/wrap |
nixnax | 20:5db9b77b38a6 | 72 | if ( hd == ppp.rx.tail ) break; // watch for buffer full |
nixnax | 17:4918c893d802 | 73 | ppp.rx.buf[ppp.rx.head]=pc.getc(); // insert in rx buffer |
nixnax | 20:5db9b77b38a6 | 74 | ppp.rx.head = hd; // update head pointer |
nixnax | 15:b0154c910143 | 75 | } |
nixnax | 0:2cf4880c312a | 76 | } |
nixnax | 0:2cf4880c312a | 77 | |
nixnax | 14:c65831c25aaa | 78 | int ledState=0; |
nixnax | 14:c65831c25aaa | 79 | void led1Toggle(){ |
nixnax | 14:c65831c25aaa | 80 | ledState = ledState? 0 : 1; |
nixnax | 14:c65831c25aaa | 81 | led1 = ledState; |
nixnax | 14:c65831c25aaa | 82 | } |
nixnax | 14:c65831c25aaa | 83 | |
nixnax | 22:00df34cd4d7e | 84 | int rxbufNotEmpty() // check if rx buffer has data |
nixnax | 0:2cf4880c312a | 85 | { |
nixnax | 22:00df34cd4d7e | 86 | __disable_irq(); // critical section start |
nixnax | 22:00df34cd4d7e | 87 | int notEmpty = (ppp.rx.head==ppp.rx.tail) ? 0 : 1 ; |
nixnax | 22:00df34cd4d7e | 88 | __enable_irq(); // critical section end |
nixnax | 22:00df34cd4d7e | 89 | return notEmpty; |
nixnax | 0:2cf4880c312a | 90 | } |
nixnax | 0:2cf4880c312a | 91 | |
nixnax | 0:2cf4880c312a | 92 | int pc_getBuf() // get one character from the buffer |
nixnax | 0:2cf4880c312a | 93 | { |
nixnax | 22:00df34cd4d7e | 94 | if ( rxbufNotEmpty() ) { |
nixnax | 4:a469050d5b80 | 95 | int x = ppp.rx.buf[ ppp.rx.tail ]; |
nixnax | 20:5db9b77b38a6 | 96 | __disable_irq(); // critical section start |
nixnax | 22:00df34cd4d7e | 97 | ppp.rx.tail=(ppp.rx.tail+1)&(BUFLEN-1); |
nixnax | 20:5db9b77b38a6 | 98 | __enable_irq(); // critical section end |
nixnax | 0:2cf4880c312a | 99 | return x; |
nixnax | 20:5db9b77b38a6 | 100 | } else return -1; |
nixnax | 0:2cf4880c312a | 101 | } |
nixnax | 0:2cf4880c312a | 102 | |
nixnax | 4:a469050d5b80 | 103 | void scanForConnectString(); // scan for connect attempts from pc |
nixnax | 1:9e03798d4367 | 104 | |
nixnax | 9:0992486d4a30 | 105 | void processFrame(int start, int end) { // process received frame |
nixnax | 14:c65831c25aaa | 106 | led1Toggle(); // change led1 state when frames are received |
nixnax | 15:b0154c910143 | 107 | if(start==end) { pc.putc(0x7e); return; } |
nixnax | 9:0992486d4a30 | 108 | crcReset(); |
nixnax | 9:0992486d4a30 | 109 | char * dest = ppp.pkt.buf; |
nixnax | 9:0992486d4a30 | 110 | ppp.pkt.len=0; |
nixnax | 9:0992486d4a30 | 111 | int unstuff=0; |
nixnax | 17:4918c893d802 | 112 | int idx = start; |
nixnax | 17:4918c893d802 | 113 | while(1) { |
nixnax | 9:0992486d4a30 | 114 | if (unstuff==0) { |
nixnax | 17:4918c893d802 | 115 | if (rxbuf[idx]==0x7d) unstuff=1; |
nixnax | 17:4918c893d802 | 116 | else { *dest = rxbuf[idx]; ppp.pkt.len++; dest++; crcDo(rxbuf[idx]); } |
nixnax | 12:db0dc91f0231 | 117 | } else { // unstuff |
nixnax | 17:4918c893d802 | 118 | *dest = rxbuf[idx]^0x20; ppp.pkt.len++; dest++; crcDo(rxbuf[idx]^0x20); |
nixnax | 9:0992486d4a30 | 119 | unstuff=0; |
nixnax | 9:0992486d4a30 | 120 | } |
nixnax | 17:4918c893d802 | 121 | idx = (idx+1) & (BUFLEN-1); |
nixnax | 17:4918c893d802 | 122 | if (idx == end) break; |
nixnax | 9:0992486d4a30 | 123 | } |
nixnax | 9:0992486d4a30 | 124 | ppp.pkt.crc = crcG & 0xffff; |
nixnax | 9:0992486d4a30 | 125 | if (ppp.pkt.crc == 0xf0b8) { // check for good CRC |
nixnax | 16:cb0b80c24ba2 | 126 | void determinePacketType(); // declaration only |
nixnax | 9:0992486d4a30 | 127 | determinePacketType(); |
nixnax | 12:db0dc91f0231 | 128 | } else { // crc error |
nixnax | 15:b0154c910143 | 129 | debug(("CRC is %x Len is %d\n",ppp.pkt.crc,ppp.pkt.len)); |
nixnax | 15:b0154c910143 | 130 | for(int i=0;i<ppp.pkt.len;i++) debug(("%02x ", ppp.pkt.buf[i])); |
nixnax | 15:b0154c910143 | 131 | debug(("\n")); |
nixnax | 9:0992486d4a30 | 132 | } |
nixnax | 9:0992486d4a30 | 133 | } |
nixnax | 9:0992486d4a30 | 134 | |
nixnax | 11:f58998c24f0b | 135 | void dumpFrame() { |
nixnax | 16:cb0b80c24ba2 | 136 | for(int i=0;i<ppp.pkt.len;i++) debug(("%02x ", ppp.pkt.buf[i])); |
nixnax | 16:cb0b80c24ba2 | 137 | debug((" C=%02x %02x L=%d\n", ppp.pkt.crc&0xff, (ppp.pkt.crc>>8)&0xff, ppp.pkt.len)); |
nixnax | 16:cb0b80c24ba2 | 138 | } |
nixnax | 16:cb0b80c24ba2 | 139 | |
nixnax | 16:cb0b80c24ba2 | 140 | void hdlcPut(int ch) { // do hdlc handling of special (flag) characters |
nixnax | 16:cb0b80c24ba2 | 141 | if ( (ch<0x20) || (ch==0x7d) || (ch==0x7e) ) { pc.putc(0x7d); pc.putc(ch^0x20); } else { pc.putc(ch); } |
nixnax | 11:f58998c24f0b | 142 | } |
nixnax | 9:0992486d4a30 | 143 | |
nixnax | 9:0992486d4a30 | 144 | void sendFrame(){ |
nixnax | 17:4918c893d802 | 145 | int crc = crcBuf(ppp.pkt.buf, ppp.pkt.len-2); // update crc |
nixnax | 12:db0dc91f0231 | 146 | ppp.pkt.buf[ ppp.pkt.len-2 ] = (~crc>>0); // fcs lo (crc) |
nixnax | 12:db0dc91f0231 | 147 | ppp.pkt.buf[ ppp.pkt.len-1 ] = (~crc>>8); // fcs hi (crc) |
nixnax | 16:cb0b80c24ba2 | 148 | pc.putc(0x7e); // hdlc start-of-frame "flag" |
nixnax | 16:cb0b80c24ba2 | 149 | for(int i=0;i<ppp.pkt.len;i++) hdlcPut( ppp.pkt.buf[i] ); |
nixnax | 16:cb0b80c24ba2 | 150 | pc.putc(0x7e); // hdlc end-of-frame "flag" |
nixnax | 9:0992486d4a30 | 151 | } |
nixnax | 9:0992486d4a30 | 152 | |
nixnax | 9:0992486d4a30 | 153 | void ipRequestHandler(){ |
nixnax | 15:b0154c910143 | 154 | debug(("IPCP Conf ")); |
nixnax | 9:0992486d4a30 | 155 | if ( ppp.pkt.buf[7] != 4 ) { |
nixnax | 15:b0154c910143 | 156 | debug(("Rej\n")); // reject if any options are requested |
nixnax | 9:0992486d4a30 | 157 | ppp.pkt.buf[4]=4; |
nixnax | 9:0992486d4a30 | 158 | sendFrame(); |
nixnax | 9:0992486d4a30 | 159 | } else { |
nixnax | 15:b0154c910143 | 160 | debug(("Ack\n")); |
nixnax | 9:0992486d4a30 | 161 | ppp.pkt.buf[4]=2; // ack the minimum |
nixnax | 9:0992486d4a30 | 162 | sendFrame(); // acknowledge |
nixnax | 15:b0154c910143 | 163 | debug(("IPCP Ask\n")); |
nixnax | 9:0992486d4a30 | 164 | // send our own request now |
nixnax | 12:db0dc91f0231 | 165 | ppp.pkt.buf[4]=1; // request no options |
nixnax | 9:0992486d4a30 | 166 | ppp.pkt.buf[5]++; // next sequence |
nixnax | 9:0992486d4a30 | 167 | sendFrame(); // this is our request |
nixnax | 9:0992486d4a30 | 168 | } |
nixnax | 9:0992486d4a30 | 169 | } |
nixnax | 9:0992486d4a30 | 170 | |
nixnax | 15:b0154c910143 | 171 | void ipAckHandler(){ debug(("IPCP Grant\n")); } |
nixnax | 9:0992486d4a30 | 172 | |
nixnax | 15:b0154c910143 | 173 | void ipNackHandler(){ debug(("IPCP Nack\n")); } |
nixnax | 9:0992486d4a30 | 174 | |
nixnax | 15:b0154c910143 | 175 | void ipDefaultHandler(){ debug(("IPCP Other\n")); } |
nixnax | 9:0992486d4a30 | 176 | |
nixnax | 9:0992486d4a30 | 177 | void IPCPframe() { |
nixnax | 9:0992486d4a30 | 178 | int code = ppp.pkt.buf[4]; // packet type is here |
nixnax | 9:0992486d4a30 | 179 | switch (code) { |
nixnax | 9:0992486d4a30 | 180 | case 1: ipRequestHandler(); break; |
nixnax | 9:0992486d4a30 | 181 | case 2: ipAckHandler(); break; |
nixnax | 9:0992486d4a30 | 182 | case 3: ipNackHandler(); break; |
nixnax | 9:0992486d4a30 | 183 | default: ipDefaultHandler(); |
nixnax | 9:0992486d4a30 | 184 | } |
nixnax | 9:0992486d4a30 | 185 | } |
nixnax | 9:0992486d4a30 | 186 | |
nixnax | 10:74f8233f72c0 | 187 | void UDPpacket() { |
nixnax | 12:db0dc91f0231 | 188 | char * udpPkt = ppp.pkt.buf+4; // udp packet start |
nixnax | 16:cb0b80c24ba2 | 189 | int headerSizeIP = (( udpPkt[0]&0xf)*4); |
nixnax | 16:cb0b80c24ba2 | 190 | char * udpBlock = udpPkt + headerSizeIP; // udp info start |
nixnax | 12:db0dc91f0231 | 191 | char * udpSrc = udpBlock; // source port |
nixnax | 12:db0dc91f0231 | 192 | char * udpDst = udpBlock+2; // destination port |
nixnax | 12:db0dc91f0231 | 193 | char * udpLen = udpBlock+4; // udp data length |
nixnax | 12:db0dc91f0231 | 194 | char * udpInf = udpBlock+8; // actual start of info |
nixnax | 12:db0dc91f0231 | 195 | int srcPort = (udpSrc[0]<<8) | udpSrc[1]; |
nixnax | 12:db0dc91f0231 | 196 | int dstPort = (udpDst[0]<<8) | udpDst[1]; |
nixnax | 12:db0dc91f0231 | 197 | char * srcIP = udpPkt+12; // udp src addr |
nixnax | 12:db0dc91f0231 | 198 | char * dstIP = udpPkt+16; // udp dst addr |
nixnax | 12:db0dc91f0231 | 199 | #define UDP_HEADER_SIZE 8 |
nixnax | 12:db0dc91f0231 | 200 | int udpLength = ((udpLen[0]<<8) | udpLen[1]) - UDP_HEADER_SIZE; // size of the actual udp data |
nixnax | 15:b0154c910143 | 201 | debug(("UDP %d.%d.%d.%d:%d ", srcIP[0],srcIP[1],srcIP[2],srcIP[3],srcPort)); |
nixnax | 15:b0154c910143 | 202 | debug(("%d.%d.%d.%d:%d ", dstIP[1],dstIP[1],dstIP[1],dstIP[1],dstPort)); |
nixnax | 15:b0154c910143 | 203 | debug(("Len %d ", udpLength)); |
nixnax | 13:d882b8a042b4 | 204 | int printSize = udpLength; if (printSize > 20) printSize = 20; // print only first 20 characters |
nixnax | 16:cb0b80c24ba2 | 205 | for (int i=0; i<printSize; i++) { char ch = udpInf[i]; if (ch>31 && ch<127) { debug(("%c", ch)); } else { debug(("_")); } } |
nixnax | 15:b0154c910143 | 206 | debug(("\n")); |
nixnax | 12:db0dc91f0231 | 207 | } |
nixnax | 11:f58998c24f0b | 208 | |
nixnax | 11:f58998c24f0b | 209 | int dataCheckSum(char * ptr, int len) { |
nixnax | 23:af88d429bed1 | 210 | int sum=0; int placeHolder; |
nixnax | 25:0b0450e1b08b | 211 | if (len&1) { placeHolder = ptr[len-1]; ptr[len-1]=0; } // when length is odd zero stuff |
nixnax | 11:f58998c24f0b | 212 | for (int i=0;i<len/2;i++) { |
nixnax | 25:0b0450e1b08b | 213 | int hi = *ptr; ptr++; int lo = *ptr; ptr++; |
nixnax | 11:f58998c24f0b | 214 | int val = ( lo & 0xff ) | ( (hi<<8) & 0xff00 ); |
nixnax | 11:f58998c24f0b | 215 | sum = sum + val; |
nixnax | 11:f58998c24f0b | 216 | } |
nixnax | 11:f58998c24f0b | 217 | sum = sum + (sum>>16); |
nixnax | 25:0b0450e1b08b | 218 | if (len&1) { ptr[len-1] = placeHolder; } // restore the last byte for odd lengths |
nixnax | 12:db0dc91f0231 | 219 | return ~sum; |
nixnax | 11:f58998c24f0b | 220 | } |
nixnax | 11:f58998c24f0b | 221 | |
nixnax | 11:f58998c24f0b | 222 | void headerCheckSum() { |
nixnax | 11:f58998c24f0b | 223 | int len =(ppp.pkt.buf[4]&0xf)*4; // length of header in bytes |
nixnax | 11:f58998c24f0b | 224 | char * ptr = ppp.pkt.buf+4; // start of ip packet |
nixnax | 11:f58998c24f0b | 225 | int sum=0; |
nixnax | 11:f58998c24f0b | 226 | |
nixnax | 11:f58998c24f0b | 227 | for (int i=0;i<len/2;i++) { |
nixnax | 11:f58998c24f0b | 228 | int hi = *ptr; ptr++; |
nixnax | 11:f58998c24f0b | 229 | int lo = *ptr; ptr++; |
nixnax | 11:f58998c24f0b | 230 | int val = ( lo & 0xff ) | ( (hi<<8) & 0xff00 ); |
nixnax | 11:f58998c24f0b | 231 | sum = sum + val; |
nixnax | 11:f58998c24f0b | 232 | } |
nixnax | 11:f58998c24f0b | 233 | sum = sum + (sum>>16); |
nixnax | 11:f58998c24f0b | 234 | sum = ~sum; |
nixnax | 11:f58998c24f0b | 235 | ppp.pkt.buf[14]= (sum>>8); |
nixnax | 11:f58998c24f0b | 236 | ppp.pkt.buf[15]= (sum ); |
nixnax | 9:0992486d4a30 | 237 | } |
nixnax | 9:0992486d4a30 | 238 | |
nixnax | 11:f58998c24f0b | 239 | void ICMPpacket() { // internet control message protocol |
nixnax | 12:db0dc91f0231 | 240 | char * ipPkt = ppp.pkt.buf+4; // ip packet start |
nixnax | 12:db0dc91f0231 | 241 | char * pktLen = ipPkt+2; |
nixnax | 12:db0dc91f0231 | 242 | int packetLength = (pktLen[0]<<8) | pktLen[1]; // icmp packet length |
nixnax | 16:cb0b80c24ba2 | 243 | int headerSizeIP = (( ipPkt[0]&0xf)*4); |
nixnax | 16:cb0b80c24ba2 | 244 | char * icmpType = ipPkt + headerSizeIP; // icmp data start |
nixnax | 13:d882b8a042b4 | 245 | char * icmpSum = icmpType+2; // icmp checksum |
nixnax | 13:d882b8a042b4 | 246 | |
nixnax | 12:db0dc91f0231 | 247 | #define ICMP_TYPE_PING_REQUEST 8 |
nixnax | 12:db0dc91f0231 | 248 | if ( icmpType[0] == ICMP_TYPE_PING_REQUEST ) { |
nixnax | 12:db0dc91f0231 | 249 | char * ipTTL = ipPkt+8; // time to live |
nixnax | 12:db0dc91f0231 | 250 | ipTTL[0]--; // decrement time to live |
nixnax | 12:db0dc91f0231 | 251 | char * srcAdr = ipPkt+12; |
nixnax | 12:db0dc91f0231 | 252 | char * dstAdr = ipPkt+16; |
nixnax | 18:3e35de1bc877 | 253 | int icmpIdent = (icmpType[4]<<8)|icmpType[5]; |
nixnax | 18:3e35de1bc877 | 254 | int icmpSequence = (icmpType[6]<<8)|icmpType[7]; |
nixnax | 25:0b0450e1b08b | 255 | debug(("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 | 25:0b0450e1b08b | 256 | debug(("Ident %04x Sequence %04d ",icmpIdent,icmpSequence)); |
nixnax | 11:f58998c24f0b | 257 | char src[4]; char dst[4]; |
nixnax | 12:db0dc91f0231 | 258 | memcpy(src, srcAdr,4); |
nixnax | 12:db0dc91f0231 | 259 | memcpy(dst, dstAdr,4); |
nixnax | 12:db0dc91f0231 | 260 | memcpy(srcAdr, dst,4); |
nixnax | 12:db0dc91f0231 | 261 | memcpy(dstAdr, src,4); // swap src & dest ip |
nixnax | 12:db0dc91f0231 | 262 | char * chkSum = ipPkt+10; |
nixnax | 12:db0dc91f0231 | 263 | chkSum[0]=0; chkSum[1]=0; |
nixnax | 12:db0dc91f0231 | 264 | headerCheckSum(); // new ip header checksum |
nixnax | 12:db0dc91f0231 | 265 | #define ICMP_TYPE_ECHO_REPLY 0 |
nixnax | 16:cb0b80c24ba2 | 266 | icmpType[0]=ICMP_TYPE_ECHO_REPLY; // icmp echo reply |
nixnax | 12:db0dc91f0231 | 267 | icmpSum[0]=0; icmpSum[1]=0; // zero the checksum for recalculation |
nixnax | 16:cb0b80c24ba2 | 268 | int icmpLength = packetLength - headerSizeIP; // length of ICMP data portion |
nixnax | 16:cb0b80c24ba2 | 269 | int sum = dataCheckSum( icmpType, icmpLength); // this checksum on icmp data portion |
nixnax | 12:db0dc91f0231 | 270 | icmpSum[0]=sum>>8; icmpSum[1]=sum; // new checksum for ICMP data portion |
nixnax | 16:cb0b80c24ba2 | 271 | |
nixnax | 16:cb0b80c24ba2 | 272 | int printSize = icmpLength-8; // exclude size of icmp header |
nixnax | 25:0b0450e1b08b | 273 | char * icmpData = icmpType+8; // the actual payload data is after the header |
nixnax | 25:0b0450e1b08b | 274 | if (printSize > 10) printSize = 10; // print up to 20 characters |
nixnax | 25:0b0450e1b08b | 275 | for (int i=0; i<printSize; i++) { char ch = icmpData[i]; if (ch>31 && ch<127) { debug(("%c",ch)); } else { debug(("_")); }} |
nixnax | 25:0b0450e1b08b | 276 | debug(("\n")); |
nixnax | 25:0b0450e1b08b | 277 | |
nixnax | 15:b0154c910143 | 278 | sendFrame(); // reply to the ping |
nixnax | 25:0b0450e1b08b | 279 | |
nixnax | 12:db0dc91f0231 | 280 | } else { |
nixnax | 15:b0154c910143 | 281 | debug(("ICMP type=%d \n", icmpType[0])); |
nixnax | 11:f58998c24f0b | 282 | } |
nixnax | 11:f58998c24f0b | 283 | } |
nixnax | 11:f58998c24f0b | 284 | |
nixnax | 11:f58998c24f0b | 285 | void IGMPpacket() { // internet group management protocol |
nixnax | 15:b0154c910143 | 286 | debug(("IGMP type=%d \n", ppp.pkt.buf[28])); |
nixnax | 11:f58998c24f0b | 287 | } |
nixnax | 11:f58998c24f0b | 288 | |
nixnax | 26:11f4eb2663a7 | 289 | |
nixnax | 26:11f4eb2663a7 | 290 | void dumpHeaderIP () { |
nixnax | 26:11f4eb2663a7 | 291 | char * ipPkt = ppp.pkt.buf+4; // ip packet start |
nixnax | 26:11f4eb2663a7 | 292 | char * version = ipPkt; // top 4 bits |
nixnax | 26:11f4eb2663a7 | 293 | char * ihl = ipPkt; // bottom 4 bits |
nixnax | 26:11f4eb2663a7 | 294 | char * dscp = ipPkt+1; // top 6 bits |
nixnax | 26:11f4eb2663a7 | 295 | char * ecn = ipPkt+1; // lower 2 bits |
nixnax | 26:11f4eb2663a7 | 296 | char * pktLen = ipPkt+2; // 2 bytes |
nixnax | 26:11f4eb2663a7 | 297 | char * ident = ipPkt+4; // 2 bytes |
nixnax | 26:11f4eb2663a7 | 298 | char * flags = ipPkt+6; // 2 bits |
nixnax | 26:11f4eb2663a7 | 299 | char * ttl = ipPkt+8; // 1 byte |
nixnax | 26:11f4eb2663a7 | 300 | char * protocol = ipPkt+9; // 1 byte |
nixnax | 26:11f4eb2663a7 | 301 | char * headercheck= ipPkt+10; // 2 bytes |
nixnax | 26:11f4eb2663a7 | 302 | char * srcAdr = ipPkt+12; // 4 bytes |
nixnax | 26:11f4eb2663a7 | 303 | char * dstAdr = ipPkt+16; // 4 bytes = total of 20 bytes |
nixnax | 26:11f4eb2663a7 | 304 | |
nixnax | 26:11f4eb2663a7 | 305 | int versionIP = (version[0]>>4)&0xf; |
nixnax | 26:11f4eb2663a7 | 306 | int headerSizeIP = (ihl[0]&0xf)*4; |
nixnax | 26:11f4eb2663a7 | 307 | int dscpIP = (dscp[0]>>2)&0x3f; |
nixnax | 26:11f4eb2663a7 | 308 | int ecnIP = ecn[0]&3; |
nixnax | 26:11f4eb2663a7 | 309 | int packetLength = (pktLen[0]<<8)|pktLen[1]; // ip total packet length |
nixnax | 26:11f4eb2663a7 | 310 | int identIP = (ident[0]<<8)|ident[1]; |
nixnax | 26:11f4eb2663a7 | 311 | int flagsIP = flags[0]>>14&3; |
nixnax | 26:11f4eb2663a7 | 312 | int ttlIP = ttl[0]; |
nixnax | 26:11f4eb2663a7 | 313 | int protocolIP = protocol[0]; |
nixnax | 26:11f4eb2663a7 | 314 | int checksumIP = (headercheck[0]<<8)|headercheck[1]; |
nixnax | 26:11f4eb2663a7 | 315 | char srcIP [16]; snprintf(srcIP,16, "%d.%d.%d.%d", srcAdr[0],srcAdr[1],srcAdr[2],srcAdr[3]); |
nixnax | 26:11f4eb2663a7 | 316 | char dstIP [16]; snprintf(dstIP,16, "%d.%d.%d.%d", dstAdr[0],dstAdr[1],dstAdr[2],dstAdr[3]); |
nixnax | 26:11f4eb2663a7 | 317 | debug(("IP %s %s v%d h%d d%d e%d L%d ",srcIP,dstIP,versionIP,headerSizeIP,dscpIP,ecnIP,packetLength)); |
nixnax | 28:1aa629be05e7 | 318 | if(0) { debug(("i%04x f%d t%d p%d C%04x\n",identIP,flagsIP,ttlIP,protocolIP,checksumIP)); } |
nixnax | 26:11f4eb2663a7 | 319 | } |
nixnax | 26:11f4eb2663a7 | 320 | |
nixnax | 26:11f4eb2663a7 | 321 | void dumpHeaderTCP() { |
nixnax | 26:11f4eb2663a7 | 322 | int ipHdrLen = (ppp.pkt.buf[4]&0xf)*4; // overall length of ip packet |
nixnax | 26:11f4eb2663a7 | 323 | |
nixnax | 26:11f4eb2663a7 | 324 | char * s = ppp.pkt.buf+4+ipHdrLen; // start of tcp packet |
nixnax | 26:11f4eb2663a7 | 325 | char * seqtcp = s + 4; // 4 bytes |
nixnax | 26:11f4eb2663a7 | 326 | char * acktcp = s + 8; // 4 bytes |
nixnax | 26:11f4eb2663a7 | 327 | char * flagbitstcp = s + 12; // 9 bits |
nixnax | 26:11f4eb2663a7 | 328 | int seq = (seqtcp[0]<<24)|(seqtcp[1]<<16)|(seqtcp[2]<<8)|(seqtcp[3]); |
nixnax | 26:11f4eb2663a7 | 329 | int ack = (acktcp[0]<<24)|(acktcp[1]<<16)|(acktcp[2]<<8)|(acktcp[3]); |
nixnax | 26:11f4eb2663a7 | 330 | int flags = ((flagbitstcp[0]&1)<<8)|flagbitstcp[1]; |
nixnax | 26:11f4eb2663a7 | 331 | |
nixnax | 26:11f4eb2663a7 | 332 | int idx = 0; char flagInfo [40]; |
nixnax | 26:11f4eb2663a7 | 333 | if (flags & (1<<0)) idx=snprintf(flagInfo+idx,40, "FIN "); if (flags & (1<<1)) idx=snprintf(flagInfo+idx,40, "SYN "); |
nixnax | 26:11f4eb2663a7 | 334 | if (flags & (1<<2)) idx=snprintf(flagInfo+idx,40, "RST "); if (flags & (1<<3)) idx=snprintf(flagInfo+idx,40, "PSH "); |
nixnax | 26:11f4eb2663a7 | 335 | if (flags & (1<<4)) idx=snprintf(flagInfo+idx,40, "ACK "); if (flags & (1<<5)) idx=snprintf(flagInfo+idx,40, "URG "); |
nixnax | 26:11f4eb2663a7 | 336 | if (flags & (1<<6)) idx=snprintf(flagInfo+idx,40, "ECE "); if (flags & (1<<7)) idx=snprintf(flagInfo+idx,40, "CWR "); |
nixnax | 26:11f4eb2663a7 | 337 | if (flags & (1<<8)) idx=snprintf(flagInfo+idx,40, "NS "); |
nixnax | 26:11f4eb2663a7 | 338 | |
nixnax | 28:1aa629be05e7 | 339 | if(0) { debug(("Flag %s Seq %08x Ack %08x ", flagInfo, seq, ack)); } |
nixnax | 10:74f8233f72c0 | 340 | } |
nixnax | 10:74f8233f72c0 | 341 | |
nixnax | 26:11f4eb2663a7 | 342 | void tcpHandler() { |
nixnax | 26:11f4eb2663a7 | 343 | |
nixnax | 26:11f4eb2663a7 | 344 | char * ipPkt = ppp.pkt.buf+4; // ip packet start |
nixnax | 26:11f4eb2663a7 | 345 | char * headercheck= ipPkt+10; // 2 bytes |
nixnax | 26:11f4eb2663a7 | 346 | |
nixnax | 26:11f4eb2663a7 | 347 | char * ihl = ipPkt; // bottom 4 bits |
nixnax | 26:11f4eb2663a7 | 348 | char * ident = ipPkt+4; // 2 bytes |
nixnax | 26:11f4eb2663a7 | 349 | char * pktLen = ipPkt+2; // 2 bytes |
nixnax | 28:1aa629be05e7 | 350 | char * protocol = ipPkt+9; // 1 byte |
nixnax | 26:11f4eb2663a7 | 351 | char * srcAdr = ipPkt+12; // 4 bytes |
nixnax | 26:11f4eb2663a7 | 352 | char * dstAdr = ipPkt+16; // 4 bytes = total of 20 bytes |
nixnax | 26:11f4eb2663a7 | 353 | |
nixnax | 26:11f4eb2663a7 | 354 | int headerSizeIP = (ihl[0]&0xf)*4; |
nixnax | 26:11f4eb2663a7 | 355 | int packetLength = (pktLen[0]<<8)|pktLen[1]; // ip total packet length |
nixnax | 26:11f4eb2663a7 | 356 | |
nixnax | 26:11f4eb2663a7 | 357 | ident[0] = ppp.ident>>8; ident[1] = ppp.ident>>0; // stuff in our ident |
nixnax | 26:11f4eb2663a7 | 358 | |
nixnax | 28:1aa629be05e7 | 359 | int ipHdrLen = (ppp.pkt.buf[4]&0xf)*4; // length of ip header |
nixnax | 26:11f4eb2663a7 | 360 | char * s = ppp.pkt.buf+4+ipHdrLen; // start of tcp packet |
nixnax | 26:11f4eb2663a7 | 361 | char * srctcp = s + 0; // 2 bytes |
nixnax | 26:11f4eb2663a7 | 362 | char * dsttcp = s + 2; // 2 bytes |
nixnax | 28:1aa629be05e7 | 363 | char * seqtcp = s + 4; // 4 bytes |
nixnax | 28:1aa629be05e7 | 364 | char * acktcp = s + 8; // 4 bytes |
nixnax | 28:1aa629be05e7 | 365 | char * offset = s + 12; // 4 bits |
nixnax | 26:11f4eb2663a7 | 366 | char * flagbitstcp = s + 12; // 9 bits |
nixnax | 26:11f4eb2663a7 | 367 | char * checksumtcp = s + 16; // 2 bytes |
nixnax | 26:11f4eb2663a7 | 368 | |
nixnax | 26:11f4eb2663a7 | 369 | int tcpSize = packetLength - headerSizeIP; |
nixnax | 28:1aa629be05e7 | 370 | int tcpHeaderLen = ((offset[0]>>4)&0x0f)*4; // size of tcp header only |
nixnax | 28:1aa629be05e7 | 371 | int dataLen = tcpSize - tcpHeaderLen; // data is what's left after the header |
nixnax | 28:1aa629be05e7 | 372 | |
nixnax | 28:1aa629be05e7 | 373 | int seq = (seqtcp[0]<<24)|(seqtcp[1]<<16)|(seqtcp[2]<<8)|(seqtcp[3]); |
nixnax | 28:1aa629be05e7 | 374 | int ack = (acktcp[0]<<24)|(acktcp[1]<<16)|(acktcp[2]<<8)|(acktcp[3]); |
nixnax | 28:1aa629be05e7 | 375 | |
nixnax | 28:1aa629be05e7 | 376 | char * dataStart = s + tcpHeaderLen; // start of data |
nixnax | 28:1aa629be05e7 | 377 | |
nixnax | 26:11f4eb2663a7 | 378 | int flagsTCP = ((flagbitstcp[0]&1)<<8)|flagbitstcp[1]; |
nixnax | 28:1aa629be05e7 | 379 | |
nixnax | 28:1aa629be05e7 | 380 | #define TCP_FLAG_ACK (1<<4) |
nixnax | 28:1aa629be05e7 | 381 | #define TCP_FLAG_SYN (1<<1) |
nixnax | 28:1aa629be05e7 | 382 | #define TCP_FLAG_PSH (1<<3) |
nixnax | 28:1aa629be05e7 | 383 | #define TCP_FLAG_RST (1<<2) |
nixnax | 28:1aa629be05e7 | 384 | #define TCP_FLAG_FIN (1<<0) |
nixnax | 26:11f4eb2663a7 | 385 | |
nixnax | 28:1aa629be05e7 | 386 | // a simple state machine to emulate basie TCP states (e.g. webserver) |
nixnax | 28:1aa629be05e7 | 387 | |
nixnax | 28:1aa629be05e7 | 388 | int dataLenOld = dataLen; // we are updating data len but still need to use it |
nixnax | 28:1aa629be05e7 | 389 | dataLen = 0; // reset the data length to prep for a short response |
nixnax | 28:1aa629be05e7 | 390 | |
nixnax | 28:1aa629be05e7 | 391 | if ( ((flagsTCP & ~TCP_FLAG_ACK) == 0) && ((flagsTCP & TCP_FLAG_ACK) != 0) ) { |
nixnax | 28:1aa629be05e7 | 392 | if (dataLenOld > 0) { // they sent data in the ack |
nixnax | 28:1aa629be05e7 | 393 | ack = seq + dataLenOld; // we update to show we know |
nixnax | 28:1aa629be05e7 | 394 | seq = ppp.seq; |
nixnax | 28:1aa629be05e7 | 395 | } |
nixnax | 28:1aa629be05e7 | 396 | else { |
nixnax | 28:1aa629be05e7 | 397 | if (ack <= ppp.seq) return; // just an empty ack |
nixnax | 28:1aa629be05e7 | 398 | ppp.seq = ack; // update our count |
nixnax | 28:1aa629be05e7 | 399 | ack = seq; |
nixnax | 28:1aa629be05e7 | 400 | seq = ppp.seq; |
nixnax | 28:1aa629be05e7 | 401 | } |
nixnax | 28:1aa629be05e7 | 402 | } |
nixnax | 28:1aa629be05e7 | 403 | else if ( (flagsTCP & TCP_FLAG_FIN) != 0 ) { // got FIN |
nixnax | 28:1aa629be05e7 | 404 | flagbitstcp[1] |= TCP_FLAG_ACK; // do a syn-ack |
nixnax | 28:1aa629be05e7 | 405 | ack = seq; |
nixnax | 28:1aa629be05e7 | 406 | seq = ppp.seq; |
nixnax | 28:1aa629be05e7 | 407 | } |
nixnax | 28:1aa629be05e7 | 408 | else if ( (flagsTCP & TCP_FLAG_SYN) != 0 ) { // got SYN |
nixnax | 28:1aa629be05e7 | 409 | flagbitstcp[1] |= TCP_FLAG_ACK; // do a syn-ack |
nixnax | 28:1aa629be05e7 | 410 | ack = seq + 1; |
nixnax | 28:1aa629be05e7 | 411 | seq = ppp.seq-1; |
nixnax | 28:1aa629be05e7 | 412 | } |
nixnax | 28:1aa629be05e7 | 413 | else if ( (flagsTCP & TCP_FLAG_PSH) != 0 ) { // respond to push with ack |
nixnax | 28:1aa629be05e7 | 414 | flagbitstcp[1] = TCP_FLAG_ACK; |
nixnax | 28:1aa629be05e7 | 415 | int temp = ack; |
nixnax | 28:1aa629be05e7 | 416 | ack = seq + dataLenOld; |
nixnax | 28:1aa629be05e7 | 417 | ppp.seq = temp; |
nixnax | 28:1aa629be05e7 | 418 | seq = temp; |
nixnax | 28:1aa629be05e7 | 419 | if ( strncmp(dataStart, "GET / HTTP/1.1", 14) == 0) { // check for web client |
nixnax | 28:1aa629be05e7 | 420 | dataLen = 3*32; // extend the data |
nixnax | 28:1aa629be05e7 | 421 | memset(dataStart,0, dataLen ); |
nixnax | 28:1aa629be05e7 | 422 | sprintf(dataStart,"HTTP/1.1 200 OK\r\nTransfer-Encoding: chunked; charset=utf-8\r\nF\r\nmbed-PPP-Blinky\r\n\r\n0\r\n\r\n"); |
nixnax | 28:1aa629be05e7 | 423 | } |
nixnax | 28:1aa629be05e7 | 424 | } |
nixnax | 28:1aa629be05e7 | 425 | |
nixnax | 28:1aa629be05e7 | 426 | // now we have to redo all the header sizes |
nixnax | 28:1aa629be05e7 | 427 | |
nixnax | 28:1aa629be05e7 | 428 | int newPacketSize = headerSizeIP + tcpHeaderLen + dataLen; |
nixnax | 28:1aa629be05e7 | 429 | pktLen[0] = (newPacketSize>>8); pktLen[1]=newPacketSize; // ip total packet size |
nixnax | 28:1aa629be05e7 | 430 | ppp.pkt.len = newPacketSize+6; // ppp packet length |
nixnax | 28:1aa629be05e7 | 431 | tcpSize = tcpHeaderLen + dataLen; // tcp packet size |
nixnax | 26:11f4eb2663a7 | 432 | |
nixnax | 28:1aa629be05e7 | 433 | // redo all the header stuff |
nixnax | 28:1aa629be05e7 | 434 | |
nixnax | 28:1aa629be05e7 | 435 | acktcp[0]=ack>>24; acktcp[1]=ack>>16; acktcp[2]=ack>>8; acktcp[3]=ack>>0; // save ack |
nixnax | 28:1aa629be05e7 | 436 | seqtcp[0]=seq>>24; seqtcp[1]=seq>>16; seqtcp[2]=seq>>8; seqtcp[3]=seq>>0; // save seq |
nixnax | 26:11f4eb2663a7 | 437 | |
nixnax | 28:1aa629be05e7 | 438 | char src[4]; char dst[4]; memcpy(src, srcAdr,4); memcpy(dst, dstAdr,4); |
nixnax | 28:1aa629be05e7 | 439 | memcpy(srcAdr, dst,4); memcpy(dstAdr, src,4); // swap ip address source/dest |
nixnax | 26:11f4eb2663a7 | 440 | char psrc[2]; char pdst[2]; memcpy(psrc, srctcp,2); memcpy(pdst, dsttcp,2); |
nixnax | 26:11f4eb2663a7 | 441 | memcpy(srctcp, pdst,2); memcpy(dsttcp, psrc,2); // swap ip port source/dest |
nixnax | 28:1aa629be05e7 | 442 | |
nixnax | 28:1aa629be05e7 | 443 | headercheck[0]=0; headercheck[1]=0; headerCheckSum(); // redo the ip header checksum |
nixnax | 26:11f4eb2663a7 | 444 | char pseudoHeader[12]; int sum; char temp[12]; // for the terrible pseudoheader checksum |
nixnax | 26:11f4eb2663a7 | 445 | memcpy( pseudoHeader+0, srcAdr, 8); // source and destination addresses. |
nixnax | 26:11f4eb2663a7 | 446 | pseudoHeader[8]=0; pseudoHeader[9]=protocol[0]; |
nixnax | 26:11f4eb2663a7 | 447 | pseudoHeader[10]=tcpSize>>8; pseudoHeader[11]=tcpSize; |
nixnax | 26:11f4eb2663a7 | 448 | memcpy(temp, s-12, 12); // keep a copy |
nixnax | 26:11f4eb2663a7 | 449 | memcpy( s-12, pseudoHeader, 12); // put the header on the tcp packet |
nixnax | 26:11f4eb2663a7 | 450 | checksumtcp[0]=0; checksumtcp[1]=0; |
nixnax | 28:1aa629be05e7 | 451 | sum=dataCheckSum(s-12,tcpSize+12); // update TCP checksum |
nixnax | 26:11f4eb2663a7 | 452 | checksumtcp[0]=sum>>8; checksumtcp[1]=sum; |
nixnax | 26:11f4eb2663a7 | 453 | memcpy( s-12, temp, 12); // overwrite the pseudoheader |
nixnax | 26:11f4eb2663a7 | 454 | sendFrame(); // return the TCP packet |
nixnax | 26:11f4eb2663a7 | 455 | } |
nixnax | 26:11f4eb2663a7 | 456 | |
nixnax | 26:11f4eb2663a7 | 457 | void dumpDataTCP() { |
nixnax | 26:11f4eb2663a7 | 458 | int ipPktLen = (ppp.pkt.buf[6]<<8)|ppp.pkt.buf[7]; // overall length of ip packet |
nixnax | 26:11f4eb2663a7 | 459 | int ipHeaderLen = (ppp.pkt.buf[4]&0xf)*4; // length of ip header |
nixnax | 26:11f4eb2663a7 | 460 | int tcpHeaderLen = ((ppp.pkt.buf[4+ipHeaderLen+12]>>4)&0xf)*4;; // length of tcp header |
nixnax | 26:11f4eb2663a7 | 461 | int dataLen = ipPktLen - ipHeaderLen - tcpHeaderLen; // data is what's left after the two headers |
nixnax | 28:1aa629be05e7 | 462 | if(0) { debug(("TCP %d ipHeader %d tcpHeader %d Data %d\n", ipPktLen, ipHeaderLen, tcpHeaderLen, dataLen)); } // 1 for more verbose |
nixnax | 28:1aa629be05e7 | 463 | if (dataLen > 0) { debug(("%s\n",ppp.pkt.buf+4+ipHeaderLen+tcpHeaderLen)); } // show the data |
nixnax | 26:11f4eb2663a7 | 464 | } |
nixnax | 26:11f4eb2663a7 | 465 | |
nixnax | 26:11f4eb2663a7 | 466 | void TCPpacket(){ |
nixnax | 26:11f4eb2663a7 | 467 | char * ipPkt = ppp.pkt.buf+4; // ip packet start |
nixnax | 26:11f4eb2663a7 | 468 | char * version = ipPkt; // top 4 bits |
nixnax | 26:11f4eb2663a7 | 469 | char * ihl = ipPkt; // bottom 4 bits |
nixnax | 26:11f4eb2663a7 | 470 | char * dscp = ipPkt+1; // top 6 bits |
nixnax | 26:11f4eb2663a7 | 471 | char * ecn = ipPkt+1; // lower 2 bits |
nixnax | 26:11f4eb2663a7 | 472 | char * pktLen = ipPkt+2; // 2 bytes |
nixnax | 26:11f4eb2663a7 | 473 | char * ident = ipPkt+4; // 2 bytes |
nixnax | 26:11f4eb2663a7 | 474 | char * flags = ipPkt+6; // 2 bits |
nixnax | 26:11f4eb2663a7 | 475 | char * ttl = ipPkt+8; // 1 byte |
nixnax | 26:11f4eb2663a7 | 476 | char * protocol = ipPkt+9; // 1 byte |
nixnax | 26:11f4eb2663a7 | 477 | char * headercheck= ipPkt+10; // 2 bytes |
nixnax | 26:11f4eb2663a7 | 478 | char * srcAdr = ipPkt+12; // 4 bytes |
nixnax | 26:11f4eb2663a7 | 479 | char * dstAdr = ipPkt+16; // 4 bytes = total of 20 bytes |
nixnax | 26:11f4eb2663a7 | 480 | |
nixnax | 26:11f4eb2663a7 | 481 | int versionIP = (version[0]>>4)&0xf; |
nixnax | 26:11f4eb2663a7 | 482 | int headerSizeIP = (ihl[0]&0xf)*4; |
nixnax | 26:11f4eb2663a7 | 483 | int dscpIP = (dscp[0]>>2)&0x3f; |
nixnax | 26:11f4eb2663a7 | 484 | int ecnIP = ecn[0]&3; |
nixnax | 26:11f4eb2663a7 | 485 | int packetLength = (pktLen[0]<<8)|pktLen[1]; // ip total packet length |
nixnax | 26:11f4eb2663a7 | 486 | int identIP = (ident[0]<<8)|ident[1]; |
nixnax | 26:11f4eb2663a7 | 487 | int flagsIP = flags[0]>>14&3; |
nixnax | 26:11f4eb2663a7 | 488 | int ttlIP = ttl[0]; |
nixnax | 26:11f4eb2663a7 | 489 | int protocolIP = protocol[0]; |
nixnax | 26:11f4eb2663a7 | 490 | int checksumIP = (headercheck[0]<<8)|headercheck[1]; |
nixnax | 26:11f4eb2663a7 | 491 | char srcIP [16]; snprintf(srcIP,16, "%d.%d.%d.%d", srcAdr[0],srcAdr[1],srcAdr[2],srcAdr[3]); |
nixnax | 26:11f4eb2663a7 | 492 | char dstIP [16]; snprintf(dstIP,16, "%d.%d.%d.%d", dstAdr[0],dstAdr[1],dstAdr[2],dstAdr[3]); |
nixnax | 26:11f4eb2663a7 | 493 | debug(("IP %s %s v%d h%d d%d e%d L%d ",srcIP,dstIP,versionIP,headerSizeIP,dscpIP,ecnIP,packetLength)); |
nixnax | 26:11f4eb2663a7 | 494 | debug(("i%04x f%d t%d p%d C%04x\n",identIP,flagsIP,ttlIP,protocolIP,checksumIP)); |
nixnax | 28:1aa629be05e7 | 495 | dumpHeaderTCP(); |
nixnax | 26:11f4eb2663a7 | 496 | dumpDataTCP(); |
nixnax | 26:11f4eb2663a7 | 497 | tcpHandler(); |
nixnax | 11:f58998c24f0b | 498 | } |
nixnax | 11:f58998c24f0b | 499 | |
nixnax | 26:11f4eb2663a7 | 500 | void otherProtocol() { debug(("Other IP protocol")); } |
nixnax | 26:11f4eb2663a7 | 501 | |
nixnax | 10:74f8233f72c0 | 502 | void IPframe() { |
nixnax | 10:74f8233f72c0 | 503 | int protocol = ppp.pkt.buf[13]; |
nixnax | 10:74f8233f72c0 | 504 | switch (protocol) { |
nixnax | 11:f58998c24f0b | 505 | case 1: ICMPpacket(); break; |
nixnax | 11:f58998c24f0b | 506 | case 2: IGMPpacket(); break; |
nixnax | 11:f58998c24f0b | 507 | case 17: UDPpacket(); break; |
nixnax | 11:f58998c24f0b | 508 | case 6: TCPpacket(); break; |
nixnax | 11:f58998c24f0b | 509 | default: otherProtocol(); |
nixnax | 10:74f8233f72c0 | 510 | } |
nixnax | 10:74f8233f72c0 | 511 | } |
nixnax | 9:0992486d4a30 | 512 | |
nixnax | 9:0992486d4a30 | 513 | void LCPconfReq() { |
nixnax | 15:b0154c910143 | 514 | debug(("LCP Config ")); |
nixnax | 9:0992486d4a30 | 515 | if (ppp.pkt.buf[7] != 4) { |
nixnax | 11:f58998c24f0b | 516 | ppp.pkt.buf[4]=4; // allow only no options |
nixnax | 15:b0154c910143 | 517 | debug(("Reject\n")); |
nixnax | 9:0992486d4a30 | 518 | sendFrame(); |
nixnax | 9:0992486d4a30 | 519 | } else { |
nixnax | 9:0992486d4a30 | 520 | ppp.pkt.buf[4]=2; // ack zero conf |
nixnax | 15:b0154c910143 | 521 | debug(("Ack\n")); |
nixnax | 9:0992486d4a30 | 522 | sendFrame(); |
nixnax | 15:b0154c910143 | 523 | debug(("LCP Ask\n")); |
nixnax | 11:f58998c24f0b | 524 | ppp.pkt.buf[4]=1; // request no options |
nixnax | 9:0992486d4a30 | 525 | sendFrame(); |
nixnax | 9:0992486d4a30 | 526 | } |
nixnax | 9:0992486d4a30 | 527 | } |
nixnax | 9:0992486d4a30 | 528 | |
nixnax | 9:0992486d4a30 | 529 | void LCPconfAck() { |
nixnax | 15:b0154c910143 | 530 | debug(("LCP Ack\n")); |
nixnax | 9:0992486d4a30 | 531 | } |
nixnax | 9:0992486d4a30 | 532 | |
nixnax | 9:0992486d4a30 | 533 | void LCPend(){ |
nixnax | 15:b0154c910143 | 534 | debug(("LCP End\n")); |
nixnax | 12:db0dc91f0231 | 535 | ppp.online=0; // start hunting for connect string again |
nixnax | 9:0992486d4a30 | 536 | ppp.pkt.buf[4]=6; |
nixnax | 12:db0dc91f0231 | 537 | sendFrame(); // acknowledge |
nixnax | 9:0992486d4a30 | 538 | } |
nixnax | 9:0992486d4a30 | 539 | |
nixnax | 9:0992486d4a30 | 540 | void LCPother(){ |
nixnax | 15:b0154c910143 | 541 | debug(("LCP Other\n")); |
nixnax | 12:db0dc91f0231 | 542 | dumpFrame(); |
nixnax | 9:0992486d4a30 | 543 | } |
nixnax | 9:0992486d4a30 | 544 | |
nixnax | 9:0992486d4a30 | 545 | void LCPframe(){ |
nixnax | 9:0992486d4a30 | 546 | int code = ppp.pkt.buf[4]; |
nixnax | 9:0992486d4a30 | 547 | switch (code) { |
nixnax | 12:db0dc91f0231 | 548 | case 1: LCPconfReq(); break; // config request |
nixnax | 12:db0dc91f0231 | 549 | case 2: LCPconfAck(); break; // config ack |
nixnax | 12:db0dc91f0231 | 550 | case 5: LCPend(); break; // end connection |
nixnax | 12:db0dc91f0231 | 551 | default: LCPother(); |
nixnax | 9:0992486d4a30 | 552 | } |
nixnax | 9:0992486d4a30 | 553 | } |
nixnax | 9:0992486d4a30 | 554 | |
nixnax | 12:db0dc91f0231 | 555 | void discardedFrame() { |
nixnax | 15:b0154c910143 | 556 | debug(("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 | 557 | } |
nixnax | 9:0992486d4a30 | 558 | |
nixnax | 9:0992486d4a30 | 559 | void determinePacketType() { |
nixnax | 15:b0154c910143 | 560 | if ( ppp.pkt.buf[0] != 0xff ) { debug(("byte0 != ff\n")); return;} |
nixnax | 15:b0154c910143 | 561 | if ( ppp.pkt.buf[1] != 3 ) { debug(("byte1 != 3\n")); return;} |
nixnax | 15:b0154c910143 | 562 | if ( ppp.pkt.buf[3] != 0x21 ) { debug(("byte2 != 21\n")); return;} |
nixnax | 9:0992486d4a30 | 563 | int packetType = ppp.pkt.buf[2]; |
nixnax | 9:0992486d4a30 | 564 | switch (packetType) { |
nixnax | 12:db0dc91f0231 | 565 | case 0xc0: LCPframe(); break; // link control |
nixnax | 12:db0dc91f0231 | 566 | case 0x80: IPCPframe(); break; // IP control |
nixnax | 12:db0dc91f0231 | 567 | case 0x00: IPframe(); break; // IP itself |
nixnax | 12:db0dc91f0231 | 568 | default: discardedFrame(); |
nixnax | 9:0992486d4a30 | 569 | } |
nixnax | 9:0992486d4a30 | 570 | } |
nixnax | 9:0992486d4a30 | 571 | |
nixnax | 9:0992486d4a30 | 572 | void scanForConnectString() { |
nixnax | 9:0992486d4a30 | 573 | if ( ppp.online==0 ) { |
nixnax | 15:b0154c910143 | 574 | char * clientFound = strstr( (char *)rxbuf, "CLIENTCLIENT" ); // look for PC string |
nixnax | 9:0992486d4a30 | 575 | if( clientFound ) { |
nixnax | 9:0992486d4a30 | 576 | strcpy( clientFound, "FOUND!FOUND!" ); // overwrite so we don't get fixated |
nixnax | 9:0992486d4a30 | 577 | pc.printf("CLIENTSERVER"); // respond to PC |
nixnax | 9:0992486d4a30 | 578 | ppp.online=1; // we can stop looking for the string |
nixnax | 15:b0154c910143 | 579 | debug(("Connect string found\n")); |
nixnax | 9:0992486d4a30 | 580 | } |
nixnax | 9:0992486d4a30 | 581 | } |
nixnax | 9:0992486d4a30 | 582 | } |
nixnax | 9:0992486d4a30 | 583 | |
nixnax | 26:11f4eb2663a7 | 584 | int myIdent = 0; |
nixnax | 26:11f4eb2663a7 | 585 | |
nixnax | 0:2cf4880c312a | 586 | int main() |
nixnax | 0:2cf4880c312a | 587 | { |
nixnax | 14:c65831c25aaa | 588 | pc.baud(115200); // USB virtual serial port |
nixnax | 15:b0154c910143 | 589 | xx.baud(115200); // second serial port for debug(((((((( messages |
nixnax | 9:0992486d4a30 | 590 | xx.puts("\x1b[2J\x1b[HReady\n"); // VT100 code for clear screen & home |
nixnax | 4:a469050d5b80 | 591 | |
nixnax | 9:0992486d4a30 | 592 | pppInitStruct(); // initialize all the PPP properties |
nixnax | 4:a469050d5b80 | 593 | |
nixnax | 9:0992486d4a30 | 594 | pc.attach(&rxHandler,Serial::RxIrq); // start the receive handler |
nixnax | 4:a469050d5b80 | 595 | |
nixnax | 9:0992486d4a30 | 596 | int frameStartIndex, frameEndIndex; int frameBusy=0; |
nixnax | 4:a469050d5b80 | 597 | |
nixnax | 0:2cf4880c312a | 598 | while(1) { |
nixnax | 9:0992486d4a30 | 599 | if ( ppp.online==0 ) scanForConnectString(); // try to connect |
nixnax | 22:00df34cd4d7e | 600 | while ( rxbufNotEmpty() ) { |
nixnax | 1:9e03798d4367 | 601 | int rx = pc_getBuf(); |
nixnax | 4:a469050d5b80 | 602 | if (frameBusy) { |
nixnax | 4:a469050d5b80 | 603 | if (rx==FRAME_7E) { |
nixnax | 4:a469050d5b80 | 604 | frameBusy=0; // done gathering frame |
nixnax | 4:a469050d5b80 | 605 | frameEndIndex=ppp.rx.tail-1; // remember where frame ends |
nixnax | 4:a469050d5b80 | 606 | processFrame(frameStartIndex, frameEndIndex); |
nixnax | 4:a469050d5b80 | 607 | } |
nixnax | 4:a469050d5b80 | 608 | } |
nixnax | 4:a469050d5b80 | 609 | else { |
nixnax | 4:a469050d5b80 | 610 | if (rx==FRAME_7E) { |
nixnax | 4:a469050d5b80 | 611 | frameBusy=1; // start gathering frame |
nixnax | 9:0992486d4a30 | 612 | frameStartIndex=ppp.rx.tail; // remember where frame started |
nixnax | 4:a469050d5b80 | 613 | } |
nixnax | 0:2cf4880c312a | 614 | } |
nixnax | 4:a469050d5b80 | 615 | } |
nixnax | 7:ab147f5e97ac | 616 | } |
nixnax | 7:ab147f5e97ac | 617 | } |