git.zerfleddert.de Git - proxmark3-svn/blob - client/comms.c

   1 //-----------------------------------------------------------------------------
   2 // Copyright (C) 2009 Michael Gernoth <michael at gernoth.net>
   3 // Copyright (C) 2010 iZsh <izsh at fail0verflow.com>
   4 //
   5 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
   6 // at your option, any later version. See the LICENSE.txt file for the text of
   7 // the license.
   8 //-----------------------------------------------------------------------------
   9 // Code for communicating with the proxmark3 hardware.
  10 //-----------------------------------------------------------------------------
  11
  12 #include <pthread.h>
  13
  14 #include "comms.h"
  15 #include "uart.h"
  16 #include "ui.h"
  17 #include "common.h"
  18 #include "data.h"
  19 #include "util_posix.h"
  20
  21 // Declare globals.
  22
  23 // Serial port that we are communicating with the PM3 on.
  24 static serial_port sp;
  25
  26 // If TRUE, then there is no active connection to the PM3, and we will drop commands sent.
  27 static bool offline;
  28
  29 // Transmit buffer.
  30 // TODO: Use locks and execute this on the main thread, rather than the receiver
  31 // thread.  Running on the main thread means we need to be careful in the
  32 // flasher, as it means SendCommand is no longer async, and can't be used as a
  33 // buffer for a pending command when the connection is re-established.
  34 static UsbCommand txcmd;
  35 volatile static bool txcmd_pending = false;
  36
  37 // Used by UsbReceiveCommand as a ring buffer for messages that are yet to be
  38 // processed by a command handler (WaitForResponse{,Timeout})
  39 static UsbCommand cmdBuffer[CMD_BUFFER_SIZE];
  40
  41 // Points to the next empty position to write to
  42 static int cmd_head = 0;
  43
  44 // Points to the position of the last unread command
  45 static int cmd_tail = 0;
  46
  47 // to lock cmdBuffer operations from different threads
  48 static pthread_mutex_t cmdBufferMutex = PTHREAD_MUTEX_INITIALIZER;
  49
  50 // These wrappers are required because it is not possible to access a static
  51 // global variable outside of the context of a single file.
  52
  53 void SetOffline(bool new_offline) {
  54         offline = new_offline;
  55 }
  56
  57 bool IsOffline() {
  58         return offline;
  59 }
  60
  61 bool OpenProxmark(char *portname, bool waitCOMPort, int timeout) {
  62         if (!waitCOMPort) {
  63                 sp = uart_open(portname);
  64         } else {
  65                 printf("Waiting for Proxmark to appear on %s ", portname);
  66                 fflush(stdout);
  67                 int openCount = 0;
  68                 do {
  69                         sp = uart_open(portname);
  70                         msleep(1000);
  71                         printf(".");
  72                         fflush(stdout);
  73                 } while(++openCount < timeout && (sp == INVALID_SERIAL_PORT || sp == CLAIMED_SERIAL_PORT));
  74                 printf("\n");
  75         }
  76
  77         // check result of uart opening
  78         if (sp == INVALID_SERIAL_PORT) {
  79                 printf("ERROR: invalid serial port\n");
  80                 return false;
  81         } else if (sp == CLAIMED_SERIAL_PORT) {
  82                 printf("ERROR: serial port is claimed by another process\n");
  83                 return false;
  84         } else {
  85                 return true;
  86         }
  87 }
  88
  89 void CloseProxmark(void) {
  90         uart_close(sp);
  91 }
  92
  93 void SendCommand(UsbCommand *c) {
  94         #ifdef COMMS_DEBUG
  95         printf("Sending %04x cmd\n", c->cmd);
  96         #endif
  97
  98         if (offline) {
  99                 PrintAndLog("Sending bytes to proxmark failed - offline");
 100                 return;
 101     }
 102         /**
 103         The while-loop below causes hangups at times, when the pm3 unit is unresponsive
 104         or disconnected. The main console thread is alive, but comm thread just spins here.
 105         Not good.../holiman
 106         **/
 107         while(txcmd_pending);
 108
 109         txcmd = *c;
 110         txcmd_pending = true;
 111 }
 112
 113
 114 /**
 115  * @brief This method should be called when sending a new command to the pm3. In case any old
 116  *  responses from previous commands are stored in the buffer, a call to this method should clear them.
 117  *  A better method could have been to have explicit command-ACKS, so we can know which ACK goes to which
 118  *  operation. Right now we'll just have to live with this.
 119  */
 120 void clearCommandBuffer()
 121 {
 122         //This is a very simple operation
 123         pthread_mutex_lock(&cmdBufferMutex);
 124         cmd_tail = cmd_head;
 125         pthread_mutex_unlock(&cmdBufferMutex);
 126 }
 127
 128 /**
 129  * @brief storeCommand stores a USB command in a circular buffer
 130  * @param UC
 131  */
 132 void storeCommand(UsbCommand *command)
 133 {
 134         pthread_mutex_lock(&cmdBufferMutex);
 135         if( (cmd_head+1) % CMD_BUFFER_SIZE == cmd_tail)
 136         {
 137                 // If these two are equal, we're about to overwrite in the
 138                 // circular buffer.
 139                 PrintAndLog("WARNING: Command buffer about to overwrite command! This needs to be fixed!");
 140         }
 141
 142         // Store the command at the 'head' location
 143         UsbCommand* destination = &cmdBuffer[cmd_head];
 144         memcpy(destination, command, sizeof(UsbCommand));
 145
 146         cmd_head = (cmd_head +1) % CMD_BUFFER_SIZE; //increment head and wrap
 147         pthread_mutex_unlock(&cmdBufferMutex);
 148 }
 149
 150
 151 /**
 152  * @brief getCommand gets a command from an internal circular buffer.
 153  * @param response location to write command
 154  * @return 1 if response was returned, 0 if nothing has been received
 155  */
 156 int getCommand(UsbCommand* response)
 157 {
 158         pthread_mutex_lock(&cmdBufferMutex);
 159         //If head == tail, there's nothing to read, or if we just got initialized
 160         if (cmd_head == cmd_tail){
 161                 pthread_mutex_unlock(&cmdBufferMutex);
 162                 return 0;
 163         }
 164
 165         //Pick out the next unread command
 166         UsbCommand* last_unread = &cmdBuffer[cmd_tail];
 167         memcpy(response, last_unread, sizeof(UsbCommand));
 168         //Increment tail - this is a circular buffer, so modulo buffer size
 169         cmd_tail = (cmd_tail + 1) % CMD_BUFFER_SIZE;
 170
 171         pthread_mutex_unlock(&cmdBufferMutex);
 172         return 1;
 173 }
 174
 175
 176 static void UsbCommandReceived(UsbCommand *UC)
 177 {
 178         switch(UC->cmd) {
 179                 // First check if we are handling a debug message
 180                 case CMD_DEBUG_PRINT_STRING: {
 181                         char s[USB_CMD_DATA_SIZE+1];
 182                         memset(s, 0x00, sizeof(s));
 183                         size_t len = MIN(UC->arg[0],USB_CMD_DATA_SIZE);
 184                         memcpy(s,UC->d.asBytes,len);
 185                         PrintAndLog("#db# %s", s);
 186                         return;
 187                 } break;
 188
 189                 case CMD_DEBUG_PRINT_INTEGERS: {
 190                         PrintAndLog("#db# %08x, %08x, %08x       \r\n", UC->arg[0], UC->arg[1], UC->arg[2]);
 191                         return;
 192                 } break;
 193
 194                 case CMD_DOWNLOADED_RAW_ADC_SAMPLES_125K: {
 195                         // FIXME: This does unsanitised copies into memory when we don't know
 196                         // the size of the buffer.
 197                         memcpy(sample_buf+(UC->arg[0]),UC->d.asBytes,UC->arg[1]);
 198                         return;
 199                 } break;
 200
 201                 default:
 202                         storeCommand(UC);
 203                         break;
 204         }
 205
 206 }
 207
 208
 209 void
 210 #ifdef __has_attribute
 211 #if __has_attribute(force_align_arg_pointer)
 212 __attribute__((force_align_arg_pointer))
 213 #endif
 214 #endif
 215 *uart_receiver(void *targ) {
 216         receiver_arg *conn = (receiver_arg*)targ;
 217         size_t rxlen;
 218         uint8_t rx[sizeof(UsbCommand)];
 219         uint8_t *prx = rx;
 220
 221         while (conn->run) {
 222                 rxlen = 0;
 223                 if (uart_receive(sp, prx, sizeof(UsbCommand) - (prx-rx), &rxlen) && rxlen) {
 224                         prx += rxlen;
 225                         if (prx-rx < sizeof(UsbCommand)) {
 226                                 continue;
 227                         }
 228                         UsbCommandReceived((UsbCommand*)rx);
 229                 }
 230                 prx = rx;
 231
 232                 if(txcmd_pending) {
 233                         if (!uart_send(sp, (uint8_t*) &txcmd, sizeof(UsbCommand))) {
 234                                 PrintAndLog("Sending bytes to proxmark failed");
 235                         }
 236                         txcmd_pending = false;
 237                 }
 238         }
 239
 240         pthread_exit(NULL);
 241         return NULL;
 242 }
 243
 244
 245 /**
 246  * Waits for a certain response type. This method waits for a maximum of
 247  * ms_timeout milliseconds for a specified response command.
 248  *@brief WaitForResponseTimeout
 249  * @param cmd command to wait for, or CMD_UNKNOWN to take any command.
 250  * @param response struct to copy received command into.
 251  * @param ms_timeout
 252  * @param show_warning
 253  * @return true if command was returned, otherwise false
 254  */
 255 bool WaitForResponseTimeoutW(uint32_t cmd, UsbCommand* response, size_t ms_timeout, bool show_warning) {
 256
 257         UsbCommand resp;
 258
 259         #ifdef COMMS_DEBUG
 260         printf("Waiting for %04x cmd\n", cmd);
 261         #endif
 262
 263         if (response == NULL) {
 264                 response = &resp;
 265         }
 266
 267         uint64_t start_time = msclock();
 268
 269         // Wait until the command is received
 270         while (true) {
 271                 while(getCommand(response)) {
 272                         if (cmd == CMD_UNKNOWN || response->cmd == cmd) {
 273                                 return true;
 274                         }
 275                 }
 276
 277                 if (msclock() - start_time > ms_timeout) {
 278                         break;
 279                 }
 280
 281                 if (msclock() - start_time > 2000 && show_warning) {
 282                         // 2 seconds elapsed (but this doesn't mean the timeout was exceeded)
 283                         PrintAndLog("Waiting for a response from the proxmark...");
 284                         PrintAndLog("You can cancel this operation by pressing the pm3 button");
 285                         show_warning = false;
 286                 }
 287         }
 288         return false;
 289 }
 290
 291
 292 bool WaitForResponseTimeout(uint32_t cmd, UsbCommand* response, size_t ms_timeout) {
 293         return WaitForResponseTimeoutW(cmd, response, ms_timeout, true);
 294 }
 295
 296 bool WaitForResponse(uint32_t cmd, UsbCommand* response) {
 297         return WaitForResponseTimeoutW(cmd, response, -1, true);
 298 }
 299