git.rot13.org Git - goodfet/blob - client/goodfet.maxusbmass

   1 #!/usr/bin/env python
   2
   3 #USB Mass Storage Emulator
   4 #by Travis Goodspeed
   5 #with thanks to Brandon Wilson and his Linky project.
   6
   7 import sys;
   8 import binascii;
   9 import array;
  10 import time;
  11
  12 from GoodFETMAXUSB import *;
  13
  14
  15 # This constant is kinda complicated and very ugly.  The idea is that
  16 # if we take too long in any given transaction, the host will abort.
  17 # How many blocks we can send depends upon timeouts on both sides,
  18 # with (at least in Linux) the behavior that aborting early causes the
  19 # disk to reset with only warning and no real errors.  Somewhere
  20 # there's a way to provide this constant to the host, in which case
  21 # stalling and waiting for a reset will no longer be necessary.
  22
  23 MAXBLOCKSPERTRANSFER=128
  24
  25 def zeros(length):
  26     """Returns a list of zeroes of the specified length."""
  27     l=range(0,length);
  28     for foo in l:
  29         l[foo]=0;
  30     return l;
  31
  32 class GoodFETMAXUSBMass(GoodFETMAXUSBDevice):
  33     """This emulates a USB Mass Storage device."""
  34
  35     #Too much data to watch everything.
  36     usbverbose=False;
  37
  38     def getSectorData(self,lba):
  39         """Overload this to return data from a given 512-byte sector."""
  40         print "You forgot to overload getSectorData().  Returning something neighborly.";
  41         sector=[
  42             0xE9, 0x86, 0x00, 0x0A, 0x47, 0x6F, 0x6F, 0x64, 0x44, 0x69, 0x73, 0x6B, 0x20, 0x30, 0x2E, 0x30,
  43             0x31, 0x0A, 0x0D, 0x62, 0x79, 0x20, 0x54, 0x72, 0x61, 0x76, 0x69, 0x73, 0x20, 0x47, 0x6F, 0x6F,
  44             0x64, 0x73, 0x70, 0x65, 0x65, 0x64, 0x0A, 0x0A, 0x0D, 0x00, 0x59, 0x6F, 0x75, 0x20, 0x68, 0x61,
  45             0x76, 0x65, 0x20, 0x62, 0x65, 0x65, 0x6E, 0x20, 0x65, 0x61, 0x74, 0x65, 0x6E, 0x20, 0x62, 0x79,
  46             0x20, 0x61, 0x20, 0x67, 0x72, 0x75, 0x65, 0x2E, 0x20, 0x20, 0x53, 0x6F, 0x72, 0x72, 0x79, 0x2E,
  47             0x0A, 0x0D, 0x00, 0x31, 0x29, 0x20, 0x52, 0x65, 0x61, 0x64, 0x69, 0x6E, 0x67, 0x20, 0x6B, 0x65,
  48             0x72, 0x6E, 0x65, 0x6C, 0x20, 0x66, 0x72, 0x6F, 0x6D, 0x20, 0x64, 0x69, 0x73, 0x6B, 0x2E, 0x0A,
  49             0x0D, 0x00, 0x32, 0x29, 0x20, 0x45, 0x78, 0x65, 0x63, 0x75, 0x74, 0x69, 0x6E, 0x67, 0x20, 0x6B,
  50             0x65, 0x72, 0x6E, 0x65, 0x6C, 0x2E, 0x0A, 0x0D, 0x00, 0xBE, 0x03, 0x7C, 0xE8, 0x41, 0x00, 0xE8,
  51             0x7B, 0x00, 0x31, 0xC0, 0x30, 0xD2, 0xCD, 0x13, 0x0F, 0x82, 0xE8, 0x00, 0xBE, 0x53, 0x7C, 0xE8,
  52             0x2E, 0x00, 0xB8, 0xE0, 0x07, 0x8E, 0xC0, 0x31, 0xDB, 0xB8, 0x10, 0x02, 0xB5, 0x00, 0xB1, 0x02,
  53             0xB6, 0x00, 0xB2, 0x00, 0xCD, 0x13, 0x0F, 0x82, 0xCA, 0x00, 0xB8, 0x00, 0x7E, 0x89, 0xC6, 0xE8,
  54             0x7C, 0x00, 0xBE, 0x72, 0x7C, 0xE8, 0x08, 0x00, 0xEA, 0x00, 0x00, 0xE0, 0x07, 0xE8, 0xB4, 0x00,
  55             0xAC, 0x3C, 0x00, 0x74, 0x06, 0xB4, 0x0E, 0xCD, 0x10, 0xEB, 0xF5, 0xC3, 0x30, 0x78, 0x00, 0x20,
  56             0x62, 0x79, 0x74, 0x65, 0x73, 0x20, 0x6F, 0x66, 0x20, 0x6D, 0x65, 0x6D, 0x6F, 0x72, 0x79, 0x20,
  57             0x64, 0x65, 0x74, 0x65, 0x63, 0x74, 0x65, 0x64, 0x2E, 0x0A, 0x0D, 0x00, 0x53, 0x65, 0x67, 0x6D,
  58             0x65, 0x6E, 0x74, 0x73, 0x3A, 0x20, 0x00, 0x2C, 0x20, 0x00, 0x0A, 0x0D, 0x00, 0xBE, 0xDC, 0x7C,
  59             0xE8, 0xBD, 0xFF, 0xE8, 0x63, 0x00, 0xE8, 0x07, 0x00, 0xBE, 0xDF, 0x7C, 0xE8, 0xB1, 0xFF, 0xC3,
  60             0x89, 0xC3, 0xC1, 0xE8, 0x0C, 0xE8, 0x39, 0x00, 0x89, 0xD8, 0xC1, 0xE8, 0x08, 0xE8, 0x31, 0x00,
  61             0x89, 0xD8, 0xC1, 0xE8, 0x04, 0xE8, 0x29, 0x00, 0x89, 0xD8, 0xE8, 0x24, 0x00, 0xC3, 0x31, 0xC9,
  62             0xAD, 0xE8, 0xDC, 0xFF, 0xE8, 0x2C, 0x00, 0x83, 0xC1, 0x02, 0x81, 0xF9, 0x00, 0x02, 0x75, 0xF0,
  63             0xC3, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x41, 0x42, 0x43, 0x44, 0x45,
  64             0x46, 0x50, 0x56, 0x83, 0xE0, 0x0F, 0x05, 0x51, 0x7D, 0x89, 0xC6, 0xAC, 0xB4, 0x0E, 0xCD, 0x10,
  65             0x5E, 0x58, 0xC3, 0xB8, 0x20, 0x0E, 0xCD, 0x10, 0xC3, 0x31, 0xC0, 0xCD, 0x12, 0x72, 0x05, 0x85,
  66             0xC0, 0x74, 0x01, 0xC3, 0xBE, 0x2A, 0x7C, 0xE8, 0x46, 0xFF, 0xEB, 0xFE, 0xEA, 0x00, 0x00, 0xFF,
  67             0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  68             0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  69             0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  70             0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  71             0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  72             0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  73             0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x55, 0xAA
  74             ];
  75         return sector;
  76     def putSectorData(self,lba,block):
  77         """Overload this to write data to a given 512-byte sector."""
  78         print "You forgot to overload putSectorData().  Ignoring sector write.";
  79         return;
  80
  81     def getSectorCount(self):
  82         """Returns the number of viable Logical Block Addresses."""
  83         print "You forgot to overload getSectorCount().  Guessing 0x200.";
  84         return 0x200;
  85
  86     def massinit(self):
  87         """Initialize a USB Mass Storage device."""
  88         self.usb_disconnect();
  89         time.sleep(1);
  90         self.usb_connect();
  91         self.massrun();
  92
  93     def massrun(self):
  94         """Main loop of the USB Mass Storage emulator."""
  95         print "Starting a Mass Storage device.";
  96         while 1:
  97             sys.stdout.flush();
  98             self.service_irqs();
  99     def do_SETUP(self):
 100         """Handle USB Enumeration"""
 101
 102         #Grab the SETUP packet from the buffer.
 103         SUD=self.readbytes(rSUDFIFO,8);
 104
 105         #Parse the SETUP packet
 106         print "Handling a setup packet of %s" % self.setup2str(SUD);
 107         setuptype=(ord(SUD[bmRequestType])&0x60);
 108         if setuptype==0x00:
 109             self.std_request(SUD);
 110         elif setuptype==0x20:
 111             self.class_request(SUD);
 112         elif setuptype==0x40:
 113             self.vendor_request(SUD);
 114         else:
 115             print "Unknown bmRequestType=0x%02x." % ord(SUD[bmRequestType])
 116             self.STALL_EP0(SUD);
 117     def class_request(self,SUD):
 118         """Handle a class request."""
 119         requesttype=ord(SUD[bmRequestType]);
 120         request=ord(SUD[bRequest]);
 121         if requesttype==0xA1 and request==0xFE:
 122             print "Reporting 0 as the maximum LUN.";
 123             #This is a Get Max LUN request.
 124             #Return 1-byte maximum Logical Unit Number
 125             self.wreg(rEP0FIFO,0x00); # Just one LUN.
 126             self.wregAS(rEP0BC,1); # ARM and fire!
 127             return; #Don't stall.
 128         if requesttype==0x21 and request==0xff:
 129             print "Received BBB reset."
 130             self.wregAS(rEP0BC,0); # ARM and fire!
 131             return; #Don't stall.
 132         print "Stalling an unknown class request: %s" % self.setup2str(SUD);
 133         self.STALL_EP0(SUD);
 134     def vendor_request(self,SUD):
 135         """Handle a vendor request."""
 136         request=ord(SUD[bRequest]);
 137         print "Why the hell is there a vendor request?";
 138         #self.wreg(rEP0FIFO,0);
 139         self.wregAS(rEP0BC,0);
 140     def std_request(self,SUD):
 141         """Handles a standard setup request."""
 142         setuptype=ord(SUD[bRequest]);
 143         if setuptype==SR_GET_DESCRIPTOR: self.send_descriptor(SUD);
 144         #elif setuptype==SR_SET_FEATURE: self.feature(1);
 145         elif setuptype==SR_SET_CONFIGURATION: self.set_configuration(SUD);
 146         elif setuptype==SR_GET_STATUS: self.get_status(SUD);
 147         elif setuptype==SR_SET_ADDRESS: self.rregAS(rFNADDR);
 148         elif setuptype==SR_GET_INTERFACE: self.get_interface(SUD);
 149         else:
 150             #print "Stalling Unknown standard setup request type %02x" % setuptype;
 151             #self.STALL_EP0(SUD);
 152             print "Accepting unknown standard setup request type %02x" % setuptype;
 153             self.wregAS(rEP0BC,0);
 154
 155     def get_interface(self,SUD):
 156         """Handles a setup request for SR_GET_INTERFACE."""
 157         if ord(SUD[wIndexL]==0):
 158             self.wreg(rEP0FIFO,0);
 159             self.wregAS(rEP0BC,1);
 160         else:
 161             self.STALL_EP0(SUD);
 162
 163
 164
 165 #Device Descriptor
 166     DD=[
 167
 168     0x12, #length
 169     0x01, 0x00, 0x02, 0x00, 0x00, 0x00, 0x40,
 170     0x81, 0x07, #Sandisk
 171     0x50, 0x51, #SDCZ2 Cruzer Mini Flash Drive (thin)
 172     0x00, 0x03,
 173     0x01, 0x02, 0x03, #Strings
 174     0x01
 175
 176     ];
 177
 178 #Configuration Descriptor
 179     CD=[
 180
 181   0x09, #Length
 182   0x02, #Type
 183   0x20, #Total Length
 184   0x00, 0x01, 0x01, 0x00, 0xE0, 0x00, 0x09, 0x04, 0x00, 0x00,
 185   0x02, #Num Endpoints
 186   0x08, #Mass Storage Bulk Only
 187   0x06, #SCSI
 188   0x50, 0x00,
 189
 190   #OUT EP1
 191   0x07, 0x05, 0x01, 0x02, 0x40, 0x00, 0x00,
 192   #IN EP3
 193   0x07, 0x05, 0x83, 0x02, 0x40, 0x00, 0x00,
 194
 195 ];
 196     strDesc=[
 197 # STRING descriptor 0--Language string
 198 "\x04\x03\x09\x04",
 199 # [
 200 #         0x04,                 # bLength
 201 #       0x03,                   # bDescriptorType = string
 202 #       0x09,0x04               # wLANGID(L/H) = English-United Sates
 203 # ],
 204 # STRING descriptor 1--Manufacturer ID
 205 "\x10\x03G\x00o\x00o\x00d\x00F\x00E\x00T\x00",
 206 # STRING descriptor 2 - Product ID
 207 "\x1C\x03M\x00A\x00S\x00S\x00 \x00E\x00m\x00u\x00l\x00a\x00t\x00o\x00r\x00",
 208 # STRING descriptor 3 - Serial Number ID
 209 "\x14\x03S\x00/\x00N\x00 \x003\x004\x002\x000\x00E\x00"
 210 ];
 211
 212     def get_status(self,SUD):
 213         """Get the USB Setup Status."""
 214         testbyte=ord(SUD[bmRequestType])
 215
 216         #Toward Device
 217         if testbyte==0x80:
 218             self.wreg(rEP0FIFO,0x03); #Enable RWU and self-powered
 219             self.wreg(rEP0FIFO,0x00); #Second byte is always zero.
 220             self.wregAS(rEP0BC,2);    #Load byte count, arm transfer, and ack CTL.
 221         #Toward Interface
 222         elif testbyte==0x81:
 223             self.wreg(rEP0FIFO,0x00);
 224             self.wreg(rEP0FIFO,0x00); #Second byte is always zero.
 225             self.wregAS(rEP0BC,2);
 226         #Toward Endpoint
 227         elif testbyte==0x82:
 228             if(ord(SUD[wIndexL])==0x83):
 229                 print "This code almost certainly doesn't work.";
 230                 self.wreg(rEP0FIFO,0x01); #Stall EP3
 231                 self.wreg(rEP0FIFO,0x00); #Second byte is always zero.
 232                 self.wregAS(rEP0BC,2);
 233             else:
 234                 print "Stalling unknown status.";
 235                 self.STALL_EP0(SUD);
 236         else:
 237             print "Stalling unknown status.";
 238             self.STALL_EP0(SUD);
 239
 240     def do_IN3(self):
 241         """Handle IN3 input event."""
 242         # Do nothing here, as it'll be taken care of elsewhere.  The
 243         # interrupt just means that the buffer is empty, not that we
 244         # are expected to fill it.
 245
 246     def do_OUT1(self):
 247         """Handle an OUT1 output event."""
 248         l=self.rreg(rEP1OUTBC);
 249         frame=self.readbytes(rEP1OUTFIFO,l);
 250         self.handleCBW(frame);
 251
 252     lastCBW="";
 253     def handleCBW(self,cbw):
 254         """Handles an incoming Command Block Wrapper.  See USB Mass
 255         Storage Class for details."""
 256
 257         if len(cbw)!=31:
 258             print "Invalid CBW length of %i bytes.  Aborting." % len(cbw);
 259             return;
 260         sig=cbw[0:4];
 261         if sig!="USBC":
 262             print "Invalid CBW signature: %s.  Should be USBC; aborting." % sig;
 263             return;
 264         self.lastCBW=cbw;
 265
 266         dtlen=ord(cbw[8])+(ord(cbw[9])<<8)+(ord(cbw[10])<<16)+(ord(cbw[11])<<24);
 267         flags=ord(cbw[12]);
 268         dtdir=flags&0x80; # 0x80 for dev->host, 0x00 for host->dev
 269         lun=ord(cbw[13])&0x0F; # Should be zero, as we only reported one LUN.
 270         cblen=ord(cbw[14])&0x1F;
 271         cb=cbw[15:31];
 272         self.handleCB(cb,cblen,dtlen,dtdir);
 273
 274     def handleCB(self,cb,cblen,dtlen,dtdir):
 275         """Handles a command block, then replies with a CSW."""
 276         if self.usbverbose:
 277             print "Got command block, type 0x%02x requesting 0x%02x bytes" % (
 278                 ord(cb[0]), dtlen);
 279         verb=ord(cb[0]);
 280         status=00; #good, set to 1 for bad.
 281         if verb==0x00: # Test Unit Ready
 282             # Send nothing, just the success code.
 283             status=0;
 284         elif verb==0x03: # Request Sense
 285             print "Responding to Request Sense.  Needed for Macs.";
 286             response=[0x70, 0x00, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x0A,
 287                       0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0x00, 0x00,
 288                       0x00, 0x00,
 289                       0,0,0,0,0];
 290             #status=1;
 291             self.writebytes(rEP3INFIFO,
 292                             response);
 293             self.wreg(rEP3INBC,len(response));
 294         elif verb==0x12: #Inquiry
 295             #print "Responding to CB inquiry.";
 296             response=[
 297                 0x00, # 00 for Direct, 1F for "no floppy"
 298                 0x80, # make 0x80 for removable media, 0x00 for fixed
 299                 0x00, # Version
 300                 0x01, # Response Data Format
 301                 0x1f, #Additional length.
 302                 0x00, 0x00, 0x00,
 303                 #Manufacturer
 304                 ord('G'),ord('o'),ord('o'),ord('d'),ord('F'),ord('E'),ord('T'),0x20,
 305                 #Device name
 306                 ord('G'),ord('o'),ord('o'),ord('d'),ord('F'),ord('E'),ord('T'),0x20,
 307                 0x20,0x20,0x20,0x20,0x20,0x20,0x20,0x20,
 308                 ord('0'),ord('.'),ord('0'),ord('1')]
 309             #print "Sending %i byte reply to %i byte query." % (
 310             #        len(response),dtlen);
 311             while len(response)<dtlen:
 312                 response=response+[0];
 313             #while not(self.rreg(rEPIRQ)&bmIN3BAVIRQ):
 314             #    #Wait for the packet to complete before sending the next.
 315             #    print "Waiting to complete inquiry."
 316             #    pass;
 317             self.writebytes(rEP3INFIFO,
 318                             response);
 319             self.wregAS(rEP3INBC,
 320                         dtlen);
 321                         #len(response));
 322             #self.wreg(rEPIRQ,bmIN3BAVIRQ); #Clear the bit
 323             #while not(self.rreg(rEPIRQ)&bmIN3BAVIRQ):
 324             #    #Wait for the packet to complete before sending the next.
 325             #    print "Waiting to complete inquiry."
 326             #    pass;
 327         elif verb==0x1e: #Prevent/Allow Removal
 328             # Give a good status to pretend we understand.
 329             status=0x00;
 330         elif verb==0x1A or verb==0x5A: #Mode Sense (6 or 10)
 331             # I should probably send six bytes here.
 332             page=ord(cb[2])&0x3F;
 333             print "Mode Sense (6) requesting %i byte Page Code %02x" % (
 334                 dtlen,page);
 335             #This is completely wrong.
 336             response=[0x07,0,0,0, 0,0,0,0x1C];
 337             # response=[0x37,0x00,0x00,0x08,0x00,0x00,0x00,0x00, 0x00,0x00,0x02,0x00,0x01,0x0a,0x80,0x00,
 338             #           0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, 0x08,0x12,0x04,0x00,0x00,0x00,0x00,0x00,
 339             #           0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, 0x00,0x00,0x00,0x00,0x0a,0x0a,0x02,0x00,
 340             #           0x00,0x00,0x00,0x00,0xff,0xff,0x00,0x1e];
 341             if page!=0x3f:
 342                 print "Unknown page, returning empty page.";
 343                 response=[0x07,0,0,0, 0,0,0,0];
 344             self.fifo_ep3in_tx(response);
 345         elif verb==0x23: #Read Format Capacity
 346             response=[
 347                 0x00, 0,0x00,0x08,    # Capacity list length.
 348                 0,0x00,0x10,0x00,     # Number of sectors, implying 10MB.  Should come from image.
 349                 0x01,0x00,            # reserved/desciptor code.
 350                 0x02,0x00             # 512 bytes/sector.  Why is this twice?
 351                 ];
 352             self.writebytes(rEP3INFIFO,
 353                             response);
 354             self.wregAS(rEP3INBC,
 355                         len(response));
 356         elif verb==0x25: #Read Capacity
 357             lastlba=self.getSectorCount();
 358             response=[
 359                 #0x00, 0, 0x0f, 0xFF, # Last LBA
 360                 (lastlba>>24)&0xFF, (lastlba>>16)&0xFF, (lastlba>>8)&0xFF, lastlba&0xFF, # Last LBA
 361                 0x00,0x00,0x02,0x00   # Block length of 512 bytes.
 362                 ];
 363             self.writebytes(rEP3INFIFO,
 364                             response);
 365             self.wregAS(rEP3INBC,
 366                         len(response));
 367         elif verb==0x28: #READ SECTOR
 368             cbw=self.lastCBW;
 369             baselba=(
 370                 ord(cbw[20]) |
 371                 (ord(cbw[19])<<8) |
 372                 (ord(cbw[18])<<16) |
 373                 (ord(cbw[17])<<24)
 374                 );
 375             count=dtlen/512;
 376             print "Fetching %i blocks starting at  LBA %i." % (count,baselba);
 377             if count>MAXBLOCKSPERTRANSFER:
 378                 count=0;
 379                 #status=1; #Fail if we're asked to read more than 32 blocks.
 380                 #Now we need to stall EP3.  It's not acceptable to just forget to transmit.
 381                 self.wreg(rEPSTALLS,0x10);
 382                 return;
 383             for i in range(0,count):
 384                 data=self.getSectorData(baselba+i);
 385                 self.fifo_ep3in_tx(data);
 386
 387                 # for j in range(0,8):
 388                 #     #print "Sending block fragment %i,%i" % (i,j);
 389                 #     #Transmit each 64-byte block fragment, then wait for next.
 390                 #     while not(self.rreg(rEPIRQ)&bmIN3BAVIRQ): pass;
 391                 #     response=data[j*64:j*64+64];
 392                 #     self.writebytes(rEP3INFIFO,
 393                 #                     response);
 394                 #     self.wregAS(rEP3INBC,
 395                 #                 64);
 396             #sys.exit();
 397         elif verb==0x2A: #WRITE SECTOR
 398             print "Haven't implemented WRITE SECTOR.";
 399             #sys.exit();
 400         elif verb==0x1B: #EJECT/RETRACT DISK
 401             print "Haven't implemented SCSI Start Stop Unit Command (1B)";
 402             print "https://en.wikipedia.org/wiki/SCSI_Start_Stop_Unit_Command";
 403             #sys.exit();
 404         else:
 405             print "ERROR: Unknown SCSI command block verb %02x." % verb;
 406             status=0x02; #Command Failed
 407             if dtlen>0:
 408                 print "Sending %i bytes of dummy data here." % dtlen;
 409                 self.fifo_ep3in_tx(zeros(dtlen));
 410             #sys.exit(1);
 411         cbw=self.lastCBW;
 412
 413         #Now we need to send the CSW.
 414         csw=[
 415             #Standard prefix.
 416             ord('U'),ord('S'),ord('B'),ord('S'),
 417             #CBW key; must be the same as the one we're replying to.
 418             ord(cbw[4]),ord(cbw[5]),ord(cbw[6]),ord(cbw[7]),
 419             #CSW Data Residue, probably oughtn't be zeroed.
 420             0,0,0,0,
 421             #Status byte: 00 for good, 01 for bad.
 422             status];
 423         self.writebytes(rEP3INFIFO,
 424                         csw);
 425         self.wregAS(rEP3INBC,len(csw));
 426
 427
 428         return;
 429
 430 class GoodFETMAXUSBMassFile(GoodFETMAXUSBMass):
 431     """This emulates a USB Mass Storage Device, providing a file as
 432     its image.  Writes are not yet supported, and this is very slow.
 433     Performance hacks will come after the code stabilizes."""
 434
 435     datafile=None;
 436     datafilelen=None;
 437     def openImage(self,filename):
 438         """Opens an image for use.  Call this *before* massinit()."""
 439         self.datafile=open(filename,"rb");
 440         print "Opened an image with %i blocks." % self.getSectorCount();
 441     def putSectorData(self,lba,block):
 442         """Writes a 512-byte sector to the lba address."""
 443         print "Writes aren't yet supported.";
 444         return;
 445
 446     def getSectorData(self,lba):
 447         """Returns data from a 512-byte sector."""
 448         toret="";
 449
 450         #Seek to the appropraite block.
 451         #print "Seeking to position %i"% (lba*512)
 452         self.datafile.seek(lba*512,0);
 453         pos=self.datafile.tell();
 454         if pos!=lba*512:
 455             print "SEEK ERROR: Seeked to %i (lba=%i), but now I'm at %i (lba=%i)" % (
 456                 lba*512,lba,
 457                 pos,pos/512);
 458             #sys.exit();
 459
 460         #Dump the data out, assuming no blocking and filling with nonsense.
 461         toret=self.datafile.read(512);
 462         if len(toret)<512:
 463             print "Holy hell, I only have %i bytes of 512." % len(toret);
 464
 465         toretbytes=range(0,len(toret));
 466         for b in range(0,len(toret)): toretbytes[b]=ord(toret[b]);
 467         return toretbytes;
 468
 469     def getSectorCount(self):
 470         """Returns the number of viable Logical Block Addresses."""
 471
 472         # Python must have a better way to read a file length, but for
 473         # now we just read the whole damned thing and then throw it
 474         # away.  With present performance, we can't read anything
 475         # large enough for this to be a problem.
 476         if self.datafilelen==None:
 477             self.datafile.seek(0);
 478             self.datafilelen=len(self.datafile.read());
 479         if self.datafilelen%512!=0:
 480             print "ERROR: Image does not have an integer number of blocks!"
 481             print "%i \% 512 == %i" % (self.datafilelen,
 482                                        self.datafilelen%512);
 483             sys.exit();
 484         return self.datafilelen/512-1;
 485
 486 if(len(sys.argv)==1):
 487     print "Usage: %s disk.img\n" % sys.argv[0];
 488     sys.exit();
 489
 490
 491 #Initialize FET and set baud rate
 492 client=GoodFETMAXUSBMassFile();
 493 client.serInit()
 494
 495 client.openImage(sys.argv[1]);
 496
 497 client.MAXUSBsetup();
 498 client.massinit();
 499