gpxe/src/net/tcp/ftp.c

   1 #include <stdint.h>
   2 #include <stdlib.h>
   3 #include <stdio.h>
   4 #include <string.h>
   5 #include <assert.h>
   6 #include <errno.h>
   7 #include <byteswap.h>
   8 #include <gpxe/socket.h>
   9 #include <gpxe/tcpip.h>
  10 #include <gpxe/in.h>
  11 #include <gpxe/xfer.h>
  12 #include <gpxe/open.h>
  13 #include <gpxe/uri.h>
  14 #include <gpxe/features.h>
  15 #include <gpxe/ftp.h>
  16
  17 /** @file
  18  *
  19  * File transfer protocol
  20  *
  21  */
  22
  23 FEATURE ( FEATURE_PROTOCOL, "FTP", DHCP_EB_FEATURE_FTP, 1 );
  24
  25 /**
  26  * FTP states
  27  *
  28  * These @b must be sequential, i.e. a successful FTP session must
  29  * pass through each of these states in order.
  30  */
  31 enum ftp_state {
  32         FTP_CONNECT = 0,
  33         FTP_USER,
  34         FTP_PASS,
  35         FTP_TYPE,
  36         FTP_PASV,
  37         FTP_RETR,
  38         FTP_QUIT,
  39         FTP_DONE,
  40 };
  41
  42 /**
  43  * An FTP request
  44  *
  45  */
  46 struct ftp_request {
  47         /** Reference counter */
  48         struct refcnt refcnt;
  49         /** Data transfer interface */
  50         struct xfer_interface xfer;
  51
  52         /** URI being fetched */
  53         struct uri *uri;
  54         /** FTP control channel interface */
  55         struct xfer_interface control;
  56         /** FTP data channel interface */
  57         struct xfer_interface data;
  58
  59         /** Current state */
  60         enum ftp_state state;
  61         /** Buffer to be filled with data received via the control channel */
  62         char *recvbuf;
  63         /** Remaining size of recvbuf */
  64         size_t recvsize;
  65         /** FTP status code, as text */
  66         char status_text[5];
  67         /** Passive-mode parameters, as text */
  68         char passive_text[24]; /* "aaa,bbb,ccc,ddd,eee,fff" */
  69 };
  70
  71 /**
  72  * Free FTP request
  73  *
  74  * @v refcnt            Reference counter
  75  */
  76 static void ftp_free ( struct refcnt *refcnt ) {
  77         struct ftp_request *ftp =
  78                 container_of ( refcnt, struct ftp_request, refcnt );
  79
  80         DBGC ( ftp, "FTP %p freed\n", ftp );
  81
  82         uri_put ( ftp->uri );
  83         free ( ftp );
  84 }
  85
  86 /**
  87  * Mark FTP operation as complete
  88  *
  89  * @v ftp               FTP request
  90  * @v rc                Return status code
  91  */
  92 static void ftp_done ( struct ftp_request *ftp, int rc ) {
  93
  94         DBGC ( ftp, "FTP %p completed (%s)\n", ftp, strerror ( rc ) );
  95
  96         /* Close all data transfer interfaces */
  97         xfer_nullify ( &ftp->xfer );
  98         xfer_close ( &ftp->xfer, rc );
  99         xfer_nullify ( &ftp->control );
 100         xfer_close ( &ftp->control, rc );
 101         xfer_nullify ( &ftp->data );
 102         xfer_close ( &ftp->data, rc );
 103 }
 104
 105 /*****************************************************************************
 106  *
 107  * FTP control channel
 108  *
 109  */
 110
 111 /**
 112  * FTP control channel strings
 113  *
 114  * These are used as printf() format strings.  Since only one of them
 115  * (RETR) takes an argument, we always supply that argument to the
 116  * snprintf() call.
 117  */
 118 static const char * ftp_strings[] = {
 119         [FTP_CONNECT]   = "",
 120         [FTP_USER]      = "USER anonymous\r\n",
 121         [FTP_PASS]      = "PASS etherboot@etherboot.org\r\n",
 122         [FTP_TYPE]      = "TYPE I\r\n",
 123         [FTP_PASV]      = "PASV\r\n",
 124         [FTP_RETR]      = "RETR %s\r\n",
 125         [FTP_QUIT]      = "QUIT\r\n",
 126         [FTP_DONE]      = "",
 127 };
 128
 129 /**
 130  * Handle control channel being closed
 131  *
 132  * @v control           FTP control channel interface
 133  * @v rc                Reason for close
 134  *
 135  * When the control channel is closed, the data channel must also be
 136  * closed, if it is currently open.
 137  */
 138 static void ftp_control_close ( struct xfer_interface *control, int rc ) {
 139         struct ftp_request *ftp =
 140                 container_of ( control, struct ftp_request, control );
 141
 142         DBGC ( ftp, "FTP %p control connection closed: %s\n",
 143                ftp, strerror ( rc ) );
 144
 145         /* Complete FTP operation */
 146         ftp_done ( ftp, rc );
 147 }
 148
 149 /**
 150  * Parse FTP byte sequence value
 151  *
 152  * @v text              Text string
 153  * @v value             Value buffer
 154  * @v len               Length of value buffer
 155  *
 156  * This parses an FTP byte sequence value (e.g. the "aaa,bbb,ccc,ddd"
 157  * form for IP addresses in PORT commands) into a byte sequence.  @c
 158  * *text will be updated to point beyond the end of the parsed byte
 159  * sequence.
 160  *
 161  * This function is safe in the presence of malformed data, though the
 162  * output is undefined.
 163  */
 164 static void ftp_parse_value ( char **text, uint8_t *value, size_t len ) {
 165         do {
 166                 *(value++) = strtoul ( *text, text, 10 );
 167                 if ( **text )
 168                         (*text)++;
 169         } while ( --len );
 170 }
 171
 172 /**
 173  * Handle an FTP control channel response
 174  *
 175  * @v ftp               FTP request
 176  *
 177  * This is called once we have received a complete response line.
 178  */
 179 static void ftp_reply ( struct ftp_request *ftp ) {
 180         char status_major = ftp->status_text[0];
 181         char separator = ftp->status_text[3];
 182
 183         DBGC ( ftp, "FTP %p received status %s\n", ftp, ftp->status_text );
 184
 185         /* Ignore malformed lines */
 186         if ( separator != ' ' )
 187                 return;
 188
 189         /* Ignore "intermediate" responses (1xx codes) */
 190         if ( status_major == '1' )
 191                 return;
 192
 193         /* Anything other than success (2xx) or, in the case of a
 194          * repsonse to a "USER" command, a password prompt (3xx), is a
 195          * fatal error.
 196          */
 197         if ( ! ( ( status_major == '2' ) ||
 198                  ( ( status_major == '3' ) && ( ftp->state == FTP_USER ) ) ) ){
 199                 /* Flag protocol error and close connections */
 200                 ftp_done ( ftp, -EPROTO );
 201         }
 202
 203         /* Open passive connection when we get "PASV" response */
 204         if ( ftp->state == FTP_PASV ) {
 205                 char *ptr = ftp->passive_text;
 206                 union {
 207                         struct sockaddr_in sin;
 208                         struct sockaddr sa;
 209                 } sa;
 210                 int rc;
 211
 212                 sa.sin.sin_family = AF_INET;
 213                 ftp_parse_value ( &ptr, ( uint8_t * ) &sa.sin.sin_addr,
 214                                   sizeof ( sa.sin.sin_addr ) );
 215                 ftp_parse_value ( &ptr, ( uint8_t * ) &sa.sin.sin_port,
 216                                   sizeof ( sa.sin.sin_port ) );
 217                 if ( ( rc = xfer_open_socket ( &ftp->data, SOCK_STREAM,
 218                                                &sa.sa, NULL ) ) != 0 ) {
 219                         DBGC ( ftp, "FTP %p could not open data connection\n",
 220                                ftp );
 221                         ftp_done ( ftp, rc );
 222                         return;
 223                 }
 224         }
 225
 226         /* Move to next state */
 227         if ( ftp->state < FTP_DONE )
 228                 ftp->state++;
 229
 230         /* Send control string */
 231         if ( ftp->state < FTP_DONE ) {
 232                 DBGC ( ftp, "FTP %p sending ", ftp );
 233                 DBGC ( ftp, ftp_strings[ftp->state], ftp->uri->path );
 234                 xfer_printf ( &ftp->control, ftp_strings[ftp->state],
 235                               ftp->uri->path );
 236         }
 237 }
 238
 239 /**
 240  * Handle new data arriving on FTP control channel
 241  *
 242  * @v control           FTP control channel interface
 243  * @v data              New data
 244  * @v len               Length of new data
 245  *
 246  * Data is collected until a complete line is received, at which point
 247  * its information is passed to ftp_reply().
 248  */
 249 static int ftp_control_deliver_raw ( struct xfer_interface *control,
 250                                      const void *data, size_t len ) {
 251         struct ftp_request *ftp =
 252                 container_of ( control, struct ftp_request, control );
 253         char *recvbuf = ftp->recvbuf;
 254         size_t recvsize = ftp->recvsize;
 255         char c;
 256
 257         while ( len-- ) {
 258                 c = * ( ( char * ) data++ );
 259                 switch ( c ) {
 260                 case '\r' :
 261                 case '\n' :
 262                         /* End of line: call ftp_reply() to handle
 263                          * completed reply.  Avoid calling ftp_reply()
 264                          * twice if we receive both \r and \n.
 265                          */
 266                         if ( recvsize == 0 )
 267                                 ftp_reply ( ftp );
 268                         /* Start filling up the status code buffer */
 269                         recvbuf = ftp->status_text;
 270                         recvsize = sizeof ( ftp->status_text ) - 1;
 271                         break;
 272                 case '(' :
 273                         /* Start filling up the passive parameter buffer */
 274                         recvbuf = ftp->passive_text;
 275                         recvsize = sizeof ( ftp->passive_text ) - 1;
 276                         break;
 277                 case ')' :
 278                         /* Stop filling the passive parameter buffer */
 279                         recvsize = 0;
 280                         break;
 281                 default :
 282                         /* Fill up buffer if applicable */
 283                         if ( recvsize > 0 ) {
 284                                 *(recvbuf++) = c;
 285                                 recvsize--;
 286                         }
 287                         break;
 288                 }
 289         }
 290
 291         /* Store for next invocation */
 292         ftp->recvbuf = recvbuf;
 293         ftp->recvsize = recvsize;
 294
 295         return 0;
 296 }
 297
 298 /** FTP control channel operations */
 299 static struct xfer_interface_operations ftp_control_operations = {
 300         .close          = ftp_control_close,
 301         .vredirect      = xfer_vopen,
 302         .window         = unlimited_xfer_window,
 303         .alloc_iob      = default_xfer_alloc_iob,
 304         .deliver_iob    = xfer_deliver_as_raw,
 305         .deliver_raw    = ftp_control_deliver_raw,
 306 };
 307
 308 /*****************************************************************************
 309  *
 310  * FTP data channel
 311  *
 312  */
 313
 314 /**
 315  * Handle FTP data channel being closed
 316  *
 317  * @v data              FTP data channel interface
 318  * @v rc                Reason for closure
 319  *
 320  * When the data channel is closed, the control channel should be left
 321  * alone; the server will send a completion message via the control
 322  * channel which we'll pick up.
 323  *
 324  * If the data channel is closed due to an error, we abort the request.
 325  */
 326 static void ftp_data_closed ( struct xfer_interface *data, int rc ) {
 327         struct ftp_request *ftp =
 328                 container_of ( data, struct ftp_request, data );
 329
 330         DBGC ( ftp, "FTP %p data connection closed: %s\n",
 331                ftp, strerror ( rc ) );
 332
 333         /* If there was an error, close control channel and record status */
 334         if ( rc )
 335                 ftp_done ( ftp, rc );
 336 }
 337
 338 /**
 339  * Handle data delivery via FTP data channel
 340  *
 341  * @v xfer              FTP data channel interface
 342  * @v iobuf             I/O buffer
 343  * @v meta              Data transfer metadata, or NULL
 344  * @ret rc              Return status code
 345  */
 346 static int ftp_data_deliver_iob ( struct xfer_interface *data,
 347                                   struct io_buffer *iobuf,
 348                                   struct xfer_metadata *meta __unused ) {
 349         struct ftp_request *ftp =
 350                 container_of ( data, struct ftp_request, data );
 351         int rc;
 352
 353         if ( ( rc = xfer_deliver_iob ( &ftp->xfer, iobuf ) ) != 0 ) {
 354                 DBGC ( ftp, "FTP %p failed to deliver data: %s\n",
 355                        ftp, strerror ( rc ) );
 356                 return rc;
 357         }
 358
 359         return 0;
 360 }
 361
 362 /** FTP data channel operations */
 363 static struct xfer_interface_operations ftp_data_operations = {
 364         .close          = ftp_data_closed,
 365         .vredirect      = xfer_vopen,
 366         .window         = unlimited_xfer_window,
 367         .alloc_iob      = default_xfer_alloc_iob,
 368         .deliver_iob    = ftp_data_deliver_iob,
 369         .deliver_raw    = xfer_deliver_as_iob,
 370 };
 371
 372 /*****************************************************************************
 373  *
 374  * Data transfer interface
 375  *
 376  */
 377
 378 /**
 379  * Close FTP data transfer interface
 380  *
 381  * @v xfer              FTP data transfer interface
 382  * @v rc                Reason for close
 383  */
 384 static void ftp_xfer_closed ( struct xfer_interface *xfer, int rc ) {
 385         struct ftp_request *ftp =
 386                 container_of ( xfer, struct ftp_request, xfer );
 387
 388         DBGC ( ftp, "FTP %p data transfer interface closed: %s\n",
 389                ftp, strerror ( rc ) );
 390
 391         ftp_done ( ftp, rc );
 392 }
 393
 394 /** FTP data transfer interface operations */
 395 static struct xfer_interface_operations ftp_xfer_operations = {
 396         .close          = ftp_xfer_closed,
 397         .vredirect      = ignore_xfer_vredirect,
 398         .window         = unlimited_xfer_window,
 399         .alloc_iob      = default_xfer_alloc_iob,
 400         .deliver_iob    = xfer_deliver_as_raw,
 401         .deliver_raw    = ignore_xfer_deliver_raw,
 402 };
 403
 404 /*****************************************************************************
 405  *
 406  * URI opener
 407  *
 408  */
 409
 410 /**
 411  * Initiate an FTP connection
 412  *
 413  * @v xfer              Data transfer interface
 414  * @v uri               Uniform Resource Identifier
 415  * @ret rc              Return status code
 416  */
 417 static int ftp_open ( struct xfer_interface *xfer, struct uri *uri ) {
 418         struct ftp_request *ftp;
 419         struct sockaddr_tcpip server;
 420         int rc;
 421
 422         /* Sanity checks */
 423         if ( ! uri->path )
 424                 return -EINVAL;
 425         if ( ! uri->host )
 426                 return -EINVAL;
 427
 428         /* Allocate and populate structure */
 429         ftp = zalloc ( sizeof ( *ftp ) );
 430         if ( ! ftp )
 431                 return -ENOMEM;
 432         ftp->refcnt.free = ftp_free;
 433         xfer_init ( &ftp->xfer, &ftp_xfer_operations, &ftp->refcnt );
 434         ftp->uri = uri_get ( uri );
 435         xfer_init ( &ftp->control, &ftp_control_operations, &ftp->refcnt );
 436         xfer_init ( &ftp->data, &ftp_data_operations, &ftp->refcnt );
 437         ftp->recvbuf = ftp->status_text;
 438         ftp->recvsize = sizeof ( ftp->status_text ) - 1;
 439
 440         DBGC ( ftp, "FTP %p fetching %s\n", ftp, ftp->uri->path );
 441
 442         /* Open control connection */
 443         memset ( &server, 0, sizeof ( server ) );
 444         server.st_port = htons ( uri_port ( uri, FTP_PORT ) );
 445         if ( ( rc = xfer_open_named_socket ( &ftp->control, SOCK_STREAM,
 446                                              ( struct sockaddr * ) &server,
 447                                              uri->host, NULL ) ) != 0 )
 448                 goto err;
 449
 450         /* Attach to parent interface, mortalise self, and return */
 451         xfer_plug_plug ( &ftp->xfer, xfer );
 452         ref_put ( &ftp->refcnt );
 453         return 0;
 454
 455  err:
 456         DBGC ( ftp, "FTP %p could not create request: %s\n",
 457                ftp, strerror ( rc ) );
 458         ftp_done ( ftp, rc );
 459         ref_put ( &ftp->refcnt );
 460         return rc;
 461 }
 462
 463 /** FTP URI opener */
 464 struct uri_opener ftp_uri_opener __uri_opener = {
 465         .scheme = "ftp",
 466         .open   = ftp_open,
 467 };