+//-----------------------------------------------------------------------------
+// Copyright (C) 2009 Michael Gernoth <michael at gernoth.net>
+// Copyright (C) 2010 iZsh <izsh at fail0verflow.com>
+//
+// This code is licensed to you under the terms of the GNU GPL, version 2 or,
+// at your option, any later version. See the LICENSE.txt file for the text of
+// the license.
+//-----------------------------------------------------------------------------
+// Code for communicating with the proxmark3 hardware.
+//-----------------------------------------------------------------------------
+
+#include <pthread.h>
+
+#include "comms.h"
+#include "uart.h"
+#include "ui.h"
+#include "common.h"
+#include "data.h"
+#include "util_posix.h"
+
+// Declare globals.
+
+// Serial port that we are communicating with the PM3 on.
+static serial_port* port;
+
+// If TRUE, then there is no active connection to the PM3, and we will drop commands sent.
+static bool offline;
+
+// Transmit buffer.
+// TODO: Use locks and execute this on the main thread, rather than the receiver
+// thread. Running on the main thread means we need to be careful in the
+// flasher, as it means SendCommand is no longer async, and can't be used as a
+// buffer for a pending command when the connection is re-established.
+static UsbCommand txcmd;
+static bool txcmd_pending;
+
+// Used by UsbReceiveCommand as a ring buffer for messages that are yet to be
+// processed by a command handler (WaitForResponse{,Timeout})
+static UsbCommand cmdBuffer[CMD_BUFFER_SIZE];
+
+// Points to the next empty position to write to
+static int cmd_head = 0;
+
+// Points to the position of the last unread command
+static int cmd_tail = 0;
+
+// to lock cmdBuffer operations from different threads
+static pthread_mutex_t cmdBufferMutex = PTHREAD_MUTEX_INITIALIZER;
+
+// These wrappers are required because it is not possible to access a static
+// global variable outside of the context of a single file.
+
+void SetSerialPort(serial_port* new_port) {
+ port = new_port;
+}
+
+serial_port* GetSerialPort() {
+ return port;
+}
+
+void SetOffline(bool new_offline) {
+ offline = new_offline;
+}
+
+bool IsOffline() {
+ return offline;
+}
+
+void SendCommand(UsbCommand *c) {
+ #ifdef COMMS_DEBUG
+ printf("Sending %04x cmd\n", c->cmd);
+ #endif
+
+ if (offline) {
+ PrintAndLog("Sending bytes to proxmark failed - offline");
+ return;
+ }
+ /**
+ The while-loop below causes hangups at times, when the pm3 unit is unresponsive
+ or disconnected. The main console thread is alive, but comm thread just spins here.
+ Not good.../holiman
+ **/
+ while(txcmd_pending);
+ txcmd = *c;
+ txcmd_pending = true;
+}
+
+/**
+ * @brief This method should be called when sending a new command to the pm3. In case any old
+ * responses from previous commands are stored in the buffer, a call to this method should clear them.
+ * A better method could have been to have explicit command-ACKS, so we can know which ACK goes to which
+ * operation. Right now we'll just have to live with this.
+ */
+void clearCommandBuffer()
+{
+ //This is a very simple operation
+ pthread_mutex_lock(&cmdBufferMutex);
+ cmd_tail = cmd_head;
+ pthread_mutex_unlock(&cmdBufferMutex);
+}
+
+/**
+ * @brief storeCommand stores a USB command in a circular buffer
+ * @param UC
+ */
+void storeCommand(UsbCommand *command)
+{
+ pthread_mutex_lock(&cmdBufferMutex);
+ if( (cmd_head+1) % CMD_BUFFER_SIZE == cmd_tail)
+ {
+ // If these two are equal, we're about to overwrite in the
+ // circular buffer.
+ PrintAndLog("WARNING: Command buffer about to overwrite command! This needs to be fixed!");
+ }
+
+ // Store the command at the 'head' location
+ UsbCommand* destination = &cmdBuffer[cmd_head];
+ memcpy(destination, command, sizeof(UsbCommand));
+
+ cmd_head = (cmd_head +1) % CMD_BUFFER_SIZE; //increment head and wrap
+ pthread_mutex_unlock(&cmdBufferMutex);
+}
+
+
+/**
+ * @brief getCommand gets a command from an internal circular buffer.
+ * @param response location to write command
+ * @return 1 if response was returned, 0 if nothing has been received
+ */
+int getCommand(UsbCommand* response)
+{
+ pthread_mutex_lock(&cmdBufferMutex);
+ //If head == tail, there's nothing to read, or if we just got initialized
+ if (cmd_head == cmd_tail){
+ pthread_mutex_unlock(&cmdBufferMutex);
+ return 0;
+ }
+
+ //Pick out the next unread command
+ UsbCommand* last_unread = &cmdBuffer[cmd_tail];
+ memcpy(response, last_unread, sizeof(UsbCommand));
+ //Increment tail - this is a circular buffer, so modulo buffer size
+ cmd_tail = (cmd_tail + 1) % CMD_BUFFER_SIZE;
+
+ pthread_mutex_unlock(&cmdBufferMutex);
+ return 1;
+}
+
+//-----------------------------------------------------------------------------
+// Entry point into our code: called whenever we received a packet over USB
+// that we weren't necessarily expecting, for example a debug print.
+//-----------------------------------------------------------------------------
+void UsbCommandReceived(UsbCommand *UC)
+{
+ switch(UC->cmd) {
+
+ // First check if we are handling a debug message
+ case CMD_DEBUG_PRINT_STRING: {
+ char s[USB_CMD_DATA_SIZE+1];
+ memset(s, 0x00, sizeof(s));
+ size_t len = MIN(UC->arg[0],USB_CMD_DATA_SIZE);
+ memcpy(s,UC->d.asBytes,len);
+ PrintAndLog("#db# %s", s);
+ return;
+ }
+
+ case CMD_DEBUG_PRINT_INTEGERS: {
+ PrintAndLog("#db# %08x, %08x, %08x \r\n", UC->arg[0], UC->arg[1], UC->arg[2]);
+ return;
+ }
+
+ case CMD_DOWNLOADED_RAW_ADC_SAMPLES_125K: {
+ // FIXME: This does unsanitised copies into memory when we don't know
+ // the size of the buffer.
+ if (sample_buf) {
+ memcpy(sample_buf+(UC->arg[0]),UC->d.asBytes,UC->arg[1]);
+ }
+ return;
+ }
+
+ default: {
+ storeCommand(UC);
+ return;
+ }
+ }
+}
+
+// Gets a single command from a proxmark3 device. This should never be used
+// with the full client.
+//
+// @param conn A receiver_arg structure.
+// @param command A buffer to store the received command.
+bool ReceiveCommand(receiver_arg* conn, UsbCommand* command) {
+ // Local recieve buffer
+ size_t rxlen;
+ byte_t rx[sizeof(UsbCommand)];
+ byte_t* prx = rx;
+
+ while (conn->run) {
+ rxlen = 0;
+ if (uart_receive(port, prx, sizeof(UsbCommand) - (prx-rx), &rxlen) && rxlen) {
+ prx += rxlen;
+ if (prx-rx < sizeof(UsbCommand)) {
+ // Keep reading until we have a completed response.
+ continue;
+ }
+
+ // We have a completed response.
+ memcpy(command, rx, sizeof(UsbCommand));
+ return true;
+ }
+
+ if (prx == rx) {
+ // We got no complete command while waiting, give up control
+ return false;
+ }
+ }
+
+ // did not get a complete command before being cancelled.
+ return false;
+}
+
+// Worker thread for processing incoming events from the PM3
+void *uart_receiver(void *targ) {
+ receiver_arg *conn = (receiver_arg*)targ;
+ UsbCommand rx;
+
+ while (conn->run) {
+ #ifdef COMMS_DEBUG
+ printf("uart_receiver: get lock\n");
+ #endif
+ // Lock up receives, in case they try to take it away from us.
+ pthread_mutex_lock(&conn->recv_lock);
+ #ifdef COMMS_DEBUG
+ printf("uart_receiver: lock acquired\n");
+ #endif
+
+ if (port == NULL) {
+ #ifdef COMMS_DEBUG
+ printf("uart_receiver: port disappeared\n");
+ #endif
+ // Our port disappeared, stall. This code path matters for the flasher,
+ // where it is fiddling with the serial port under us.
+ pthread_mutex_unlock(&conn->recv_lock);
+ msleep(10);
+ continue;
+ }
+
+ bool got_command = ReceiveCommand(conn, &rx);
+ #ifdef COMMS_DEBUG
+ printf("uart_receiver: got command\n");
+ #endif
+ pthread_mutex_unlock(&conn->recv_lock);
+
+ if (got_command) {
+ UsbCommandReceived(&rx);
+ }
+
+ // We aren't normally trying to transmit in the flasher when the port would
+ // be reset, so we can just keep going at this point.
+ if (txcmd_pending) {
+ if (!uart_send(port, (byte_t*) &txcmd, sizeof(UsbCommand))) {
+ PrintAndLog("Sending bytes to proxmark failed");
+ }
+ txcmd_pending = false;
+ }
+ }
+
+ pthread_exit(NULL);
+ return NULL;
+}
+
+/**
+ * Waits for a certain response type. This method waits for a maximum of
+ * ms_timeout milliseconds for a specified response command.
+ *@brief WaitForResponseTimeout
+ * @param cmd command to wait for, or CMD_ANY to take any command.
+ * @param response struct to copy received command into.
+ * @param ms_timeout
+ * @param show_warning
+ * @return true if command was returned, otherwise false
+ */
+bool WaitForResponseTimeoutW(uint64_t cmd, UsbCommand* response, size_t ms_timeout, bool show_warning) {
+ UsbCommand resp;
+
+ #ifdef COMMS_DEBUG
+ printf("Waiting for %04x cmd\n", cmd);
+ #endif
+
+ if (response == NULL) {
+ response = &resp;
+ }
+
+ uint64_t start_time = msclock();
+
+ // Wait until the command is received
+ for (;;) {
+ while(getCommand(response)) {
+ if (cmd == CMD_ANY || response->cmd == cmd) {
+ return true;
+ }
+ }
+
+ if (msclock() - start_time > ms_timeout) {
+ // We timed out.
+ break;
+ }
+
+ if (msclock() - start_time > 2000 && show_warning) {
+ // 2 seconds elapsed (but this doesn't mean the timeout was exceeded)
+ PrintAndLog("Waiting for a response from the proxmark...");
+ PrintAndLog("Don't forget to cancel its operation first by pressing on the button");
+ break;
+ }
+ }
+ return false;
+}
+
+bool WaitForResponseTimeout(uint64_t cmd, UsbCommand* response, size_t ms_timeout) {
+ return WaitForResponseTimeoutW(cmd, response, ms_timeout, true);
+}
+
+bool WaitForResponse(uint64_t cmd, UsbCommand* response) {
+ return WaitForResponseTimeout(cmd, response, -1);
+}