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"Das U-Boot" Source Tree
1// SPDX-License-Identifier: eCos-2.0
2/*
3 *==========================================================================
4 *
5 * xyzModem.c
6 *
7 * RedBoot stream handler for xyzModem protocol
8 *
9 *==========================================================================
10 *#####DESCRIPTIONBEGIN####
11 *
12 * Author(s): gthomas
13 * Contributors: gthomas, tsmith, Yoshinori Sato
14 * Date: 2000-07-14
15 * Purpose:
16 * Description:
17 *
18 * This code is part of RedBoot (tm).
19 *
20 *####DESCRIPTIONEND####
21 *
22 *==========================================================================
23 */
24#include <xyzModem.h>
25#include <stdarg.h>
26#include <time.h>
27#include <u-boot/crc.h>
28#include <watchdog.h>
29#include <env.h>
30#include <vsprintf.h>
31
32/* Assumption - run xyzModem protocol over the console port */
33
34/* Values magic to the protocol */
35#define SOH 0x01
36#define STX 0x02
37#define ETX 0x03 /* ^C for interrupt */
38#define EOT 0x04
39#define ACK 0x06
40#define BSP 0x08
41#define NAK 0x15
42#define CAN 0x18
43#define EOF 0x1A /* ^Z for DOS officionados */
44
45/* Data & state local to the protocol */
46static struct
47{
48 int *__chan;
49 unsigned char pkt[1024], *bufp;
50 unsigned char blk, cblk, crc1, crc2;
51 unsigned char next_blk; /* Expected block */
52 int len, mode, total_retries;
53 int total_SOH, total_STX, total_CAN;
54 bool crc_mode, at_eof, tx_ack;
55 bool first_xmodem_packet;
56 ulong initial_time, timeout;
57 unsigned long file_length, read_length;
58} xyz;
59
60#define xyzModem_CHAR_TIMEOUT 2000 /* 2 seconds */
61#define xyzModem_MAX_RETRIES 20
62#define xyzModem_MAX_RETRIES_WITH_CRC 10
63#define xyzModem_CAN_COUNT 3 /* Wait for 3 CAN before quitting */
64
65typedef int cyg_int32;
66static int
67CYGACC_COMM_IF_GETC_TIMEOUT (char chan, char *c)
68{
69
70 ulong now = get_timer(0);
71 schedule();
72 while (!tstc ())
73 {
74 if (get_timer(now) > xyzModem_CHAR_TIMEOUT)
75 break;
76 }
77 if (tstc ())
78 {
79 *c = getchar();
80 return 1;
81 }
82 return 0;
83}
84
85static void
86CYGACC_COMM_IF_PUTC (char x, char y)
87{
88 putc (y);
89}
90
91/* Validate a hex character */
92__inline__ static bool
93_is_hex (char c)
94{
95 return (((c >= '0') && (c <= '9')) ||
96 ((c >= 'A') && (c <= 'F')) || ((c >= 'a') && (c <= 'f')));
97}
98
99/* Convert a single hex nibble */
100__inline__ static int
101_from_hex (char c)
102{
103 int ret = 0;
104
105 if ((c >= '0') && (c <= '9'))
106 {
107 ret = (c - '0');
108 }
109 else if ((c >= 'a') && (c <= 'f'))
110 {
111 ret = (c - 'a' + 0x0a);
112 }
113 else if ((c >= 'A') && (c <= 'F'))
114 {
115 ret = (c - 'A' + 0x0A);
116 }
117 return ret;
118}
119
120/* Convert a character to lower case */
121__inline__ static char
122_tolower (char c)
123{
124 if ((c >= 'A') && (c <= 'Z'))
125 {
126 c = (c - 'A') + 'a';
127 }
128 return c;
129}
130
131/* Parse (scan) a number */
132static bool
133parse_num (char *s, unsigned long *val, char **es, char *delim)
134{
135 bool first = true;
136 int radix = 10;
137 char c;
138 unsigned long result = 0;
139 int digit;
140
141 while (*s == ' ')
142 s++;
143 while (*s)
144 {
145 if (first && (s[0] == '0') && (_tolower (s[1]) == 'x'))
146 {
147 radix = 16;
148 s += 2;
149 }
150 first = false;
151 c = *s++;
152 if (_is_hex (c) && ((digit = _from_hex (c)) < radix))
153 {
154 /* Valid digit */
155 result = (result * radix) + digit;
156 }
157 else
158 {
159 if (delim != (char *) 0)
160 {
161 /* See if this character is one of the delimiters */
162 char *dp = delim;
163 while (*dp && (c != *dp))
164 dp++;
165 if (*dp)
166 break; /* Found a good delimiter */
167 }
168 return false; /* Malformatted number */
169 }
170 }
171 *val = result;
172 if (es != (char **) 0)
173 {
174 *es = s;
175 }
176 return true;
177}
178
179#if defined(DEBUG) && !CONFIG_IS_ENABLED(USE_TINY_PRINTF)
180/*
181 * Note: this debug setup works by storing the strings in a fixed buffer
182 */
183static char zm_debug_buf[8192];
184static char *zm_out = zm_debug_buf;
185static char *zm_out_start = zm_debug_buf;
186
187static int
188zm_dprintf(char *fmt, ...)
189{
190 int len;
191 va_list args;
192
193 va_start(args, fmt);
194 len = diag_vsprintf(zm_out, fmt, args);
195 va_end(args);
196 zm_out += len;
197 return len;
198}
199
200static void
201zm_flush (void)
202{
203 zm_out = zm_out_start;
204}
205
206static void
207zm_dump_buf (void *buf, int len)
208{
209
210}
211
212static unsigned char zm_buf[2048];
213static unsigned char *zm_bp;
214
215static void
216zm_new (void)
217{
218 zm_bp = zm_buf;
219}
220
221static void
222zm_save (unsigned char c)
223{
224 *zm_bp++ = c;
225}
226
227static void
228zm_dump (int line)
229{
230 zm_dprintf ("Packet at line: %d\n", line);
231 zm_dump_buf (zm_buf, zm_bp - zm_buf);
232}
233
234#define ZM_DEBUG(x) x
235#else
236#define ZM_DEBUG(x)
237#endif
238
239/* Wait for the line to go idle */
240static void
241xyzModem_flush (void)
242{
243 int res;
244 char c;
245 while (true)
246 {
247 res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, &c);
248 if (!res)
249 return;
250 }
251}
252
253static int
254xyzModem_get_hdr (void)
255{
256 char c;
257 int res;
258 bool hdr_found = false;
259 int i, can_total, hdr_chars;
260 unsigned short cksum;
261
262 ZM_DEBUG (zm_new ());
263 /* Find the start of a header */
264 can_total = 0;
265 hdr_chars = 0;
266
267 if (xyz.tx_ack)
268 {
269 CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK);
270 xyz.tx_ack = false;
271 }
272 while (!hdr_found)
273 {
274 res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, &c);
275 ZM_DEBUG (zm_save (c));
276 if (res)
277 {
278 hdr_chars++;
279 switch (c)
280 {
281 case SOH:
282 xyz.total_SOH++;
283 fallthrough;
284 case STX:
285 if (c == STX)
286 xyz.total_STX++;
287 hdr_found = true;
288 break;
289 case CAN:
290 case ETX:
291 xyz.total_CAN++;
292 ZM_DEBUG (zm_dump (__LINE__));
293 if (++can_total == xyzModem_CAN_COUNT)
294 {
295 return xyzModem_cancel;
296 }
297 else
298 {
299 /* Wait for multiple CAN to avoid early quits */
300 break;
301 }
302 case EOT:
303 /* EOT only supported if no noise */
304 if (hdr_chars == 1)
305 {
306 CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK);
307 ZM_DEBUG (zm_dprintf ("ACK on EOT #%d\n", __LINE__));
308 ZM_DEBUG (zm_dump (__LINE__));
309 return xyzModem_eof;
310 }
311 default:
312 /* Ignore, waiting for start of header */
313 ;
314 }
315 }
316 else
317 {
318 /* Data stream timed out */
319 xyzModem_flush (); /* Toss any current input */
320 ZM_DEBUG (zm_dump (__LINE__));
321 CYGACC_CALL_IF_DELAY_US ((cyg_int32) 250000);
322 return xyzModem_timeout;
323 }
324 }
325
326 /* Header found, now read the data */
327 res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, (char *) &xyz.blk);
328 ZM_DEBUG (zm_save (xyz.blk));
329 if (!res)
330 {
331 ZM_DEBUG (zm_dump (__LINE__));
332 return xyzModem_timeout;
333 }
334 res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, (char *) &xyz.cblk);
335 ZM_DEBUG (zm_save (xyz.cblk));
336 if (!res)
337 {
338 ZM_DEBUG (zm_dump (__LINE__));
339 return xyzModem_timeout;
340 }
341 xyz.len = (c == SOH) ? 128 : 1024;
342 xyz.bufp = xyz.pkt;
343 for (i = 0; i < xyz.len; i++)
344 {
345 res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, &c);
346 ZM_DEBUG (zm_save (c));
347 if (res)
348 {
349 xyz.pkt[i] = c;
350 }
351 else
352 {
353 ZM_DEBUG (zm_dump (__LINE__));
354 return xyzModem_timeout;
355 }
356 }
357 res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, (char *) &xyz.crc1);
358 ZM_DEBUG (zm_save (xyz.crc1));
359 if (!res)
360 {
361 ZM_DEBUG (zm_dump (__LINE__));
362 return xyzModem_timeout;
363 }
364 if (xyz.crc_mode)
365 {
366 res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, (char *) &xyz.crc2);
367 ZM_DEBUG (zm_save (xyz.crc2));
368 if (!res)
369 {
370 ZM_DEBUG (zm_dump (__LINE__));
371 return xyzModem_timeout;
372 }
373 }
374 ZM_DEBUG (zm_dump (__LINE__));
375 /* Validate the message */
376 if ((xyz.blk ^ xyz.cblk) != (unsigned char) 0xFF)
377 {
378 ZM_DEBUG (zm_dprintf
379 ("Framing error - blk: %x/%x/%x\n", xyz.blk, xyz.cblk,
380 (xyz.blk ^ xyz.cblk)));
381 ZM_DEBUG (zm_dump_buf (xyz.pkt, xyz.len));
382 xyzModem_flush ();
383 return xyzModem_frame;
384 }
385 /* Verify checksum/CRC */
386 if (xyz.crc_mode)
387 {
388 cksum = crc16_ccitt(0, xyz.pkt, xyz.len);
389 if (cksum != ((xyz.crc1 << 8) | xyz.crc2))
390 {
391 ZM_DEBUG (zm_dprintf ("CRC error - recvd: %02x%02x, computed: %x\n",
392 xyz.crc1, xyz.crc2, cksum & 0xFFFF));
393 return xyzModem_cksum;
394 }
395 }
396 else
397 {
398 cksum = 0;
399 for (i = 0; i < xyz.len; i++)
400 {
401 cksum += xyz.pkt[i];
402 }
403 if (xyz.crc1 != (cksum & 0xFF))
404 {
405 ZM_DEBUG (zm_dprintf
406 ("Checksum error - recvd: %x, computed: %x\n", xyz.crc1,
407 cksum & 0xFF));
408 return xyzModem_cksum;
409 }
410 }
411 /* If we get here, the message passes [structural] muster */
412 return 0;
413}
414
415static
416ulong
417xyzModem_get_initial_timeout (void)
418{
419 /* timeout is in seconds, non-positive timeout value is infinity */
420#if CONFIG_IS_ENABLED(ENV_SUPPORT)
421 const char *timeout_str = env_get("loadxy_timeout");
422 if (timeout_str)
423 return 1000 * simple_strtol(timeout_str, NULL, 10);
424#endif
425 return 1000 * CONFIG_CMD_LOADXY_TIMEOUT;
426}
427
428int
429xyzModem_stream_open (connection_info_t * info, int *err)
430{
431 int stat = 0;
432 int retries = xyzModem_MAX_RETRIES;
433 int crc_retries = xyzModem_MAX_RETRIES_WITH_CRC;
434
435/* ZM_DEBUG(zm_out = zm_out_start); */
436#ifdef xyzModem_zmodem
437 if (info->mode == xyzModem_zmodem)
438 {
439 *err = xyzModem_noZmodem;
440 return -1;
441 }
442#endif
443
444/* TODO: CHECK ! */
445 int dummy = 0;
446 xyz.__chan = &dummy;
447 xyz.len = 0;
448 xyz.crc_mode = true;
449 xyz.at_eof = false;
450 xyz.tx_ack = false;
451 xyz.mode = info->mode;
452 xyz.total_retries = 0;
453 xyz.total_SOH = 0;
454 xyz.total_STX = 0;
455 xyz.total_CAN = 0;
456 xyz.read_length = 0;
457 xyz.file_length = 0;
458 xyz.first_xmodem_packet = false;
459 xyz.initial_time = get_timer(0);
460 xyz.timeout = xyzModem_get_initial_timeout();
461
462 CYGACC_COMM_IF_PUTC (*xyz.__chan, (xyz.crc_mode ? 'C' : NAK));
463
464 if (xyz.mode == xyzModem_xmodem)
465 {
466 /* X-modem doesn't have an information header - exit here */
467 xyz.first_xmodem_packet = true;
468 xyz.next_blk = 1;
469 return 0;
470 }
471
472 while (!(xyz.timeout && get_timer(xyz.initial_time) > xyz.timeout))
473 {
474 if (--retries <= 0)
475 {
476 retries = xyzModem_MAX_RETRIES;
477 crc_retries = xyzModem_MAX_RETRIES_WITH_CRC;
478 xyz.crc_mode = true;
479 }
480 stat = xyzModem_get_hdr ();
481 if (stat == 0)
482 {
483 /* Y-modem file information header */
484 if (xyz.blk == 0)
485 {
486 /* skip filename */
487 while (*xyz.bufp++);
488 /* get the length */
489 parse_num ((char *) xyz.bufp, &xyz.file_length, NULL, " ");
490 /* The rest of the file name data block quietly discarded */
491 xyz.tx_ack = true;
492 }
493 xyz.next_blk = 1;
494 xyz.len = 0;
495 return 0;
496 }
497 else if (stat == xyzModem_timeout)
498 {
499 if (--crc_retries <= 0)
500 xyz.crc_mode = false;
501 CYGACC_CALL_IF_DELAY_US (5 * 100000); /* Extra delay for startup */
502 CYGACC_COMM_IF_PUTC (*xyz.__chan, (xyz.crc_mode ? 'C' : NAK));
503 xyz.total_retries++;
504 ZM_DEBUG (zm_dprintf ("NAK (%d)\n", __LINE__));
505 }
506 if (stat == xyzModem_cancel)
507 {
508 break;
509 }
510 }
511 *err = stat;
512 ZM_DEBUG (zm_flush ());
513 return -1;
514}
515
516int
517xyzModem_stream_read (char *buf, int size, int *err)
518{
519 int stat, total, len;
520 int retries;
521
522 total = 0;
523 stat = xyzModem_cancel;
524 /* Try and get 'size' bytes into the buffer */
525 while (!xyz.at_eof && xyz.len >= 0 && (size > 0))
526 {
527 if (xyz.len == 0)
528 {
529 retries = xyzModem_MAX_RETRIES;
530 while (retries-- > 0)
531 {
532 if (xyz.first_xmodem_packet && xyz.timeout &&
533 get_timer(xyz.initial_time) > xyz.timeout)
534 {
535 *err = xyzModem_timeout;
536 xyz.len = -1;
537 return total;
538 }
539
540 stat = xyzModem_get_hdr ();
541 if (stat == 0)
542 {
543 if (xyz.mode == xyzModem_xmodem && xyz.first_xmodem_packet)
544 xyz.first_xmodem_packet = false;
545 if (xyz.blk == xyz.next_blk)
546 {
547 xyz.tx_ack = true;
548 ZM_DEBUG (zm_dprintf
549 ("ACK block %d (%d)\n", xyz.blk, __LINE__));
550 xyz.next_blk = (xyz.next_blk + 1) & 0xFF;
551
552 if (xyz.mode == xyzModem_xmodem || xyz.file_length == 0)
553 {
554 /* Data blocks can be padded with ^Z (EOF) characters */
555 /* This code tries to detect and remove them */
556 if ((xyz.bufp[xyz.len - 1] == EOF) &&
557 (xyz.bufp[xyz.len - 2] == EOF) &&
558 (xyz.bufp[xyz.len - 3] == EOF))
559 {
560 while (xyz.len
561 && (xyz.bufp[xyz.len - 1] == EOF))
562 {
563 xyz.len--;
564 }
565 }
566 }
567
568 /*
569 * See if accumulated length exceeds that of the file.
570 * If so, reduce size (i.e., cut out pad bytes)
571 * Only do this for Y-modem (and Z-modem should it ever
572 * be supported since it can fall back to Y-modem mode).
573 */
574 if (xyz.mode != xyzModem_xmodem && 0 != xyz.file_length)
575 {
576 xyz.read_length += xyz.len;
577 if (xyz.read_length > xyz.file_length)
578 {
579 xyz.len -= (xyz.read_length - xyz.file_length);
580 }
581 }
582 break;
583 }
584 else if (xyz.blk == ((xyz.next_blk - 1) & 0xFF))
585 {
586 /* Just re-ACK this so sender will get on with it */
587 CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK);
588 continue; /* Need new header */
589 }
590 else
591 {
592 stat = xyzModem_sequence;
593 }
594 }
595 if (stat == xyzModem_cancel)
596 {
597 break;
598 }
599 if (stat == xyzModem_eof)
600 {
601 CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK);
602 ZM_DEBUG (zm_dprintf ("ACK (%d)\n", __LINE__));
603 if (xyz.mode == xyzModem_ymodem)
604 {
605 CYGACC_COMM_IF_PUTC (*xyz.__chan,
606 (xyz.crc_mode ? 'C' : NAK));
607 xyz.total_retries++;
608 ZM_DEBUG (zm_dprintf ("Reading Final Header\n"));
609 stat = xyzModem_get_hdr ();
610 CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK);
611 ZM_DEBUG (zm_dprintf ("FINAL ACK (%d)\n", __LINE__));
612 }
613 else
614 stat = 0;
615 xyz.at_eof = true;
616 break;
617 }
618 CYGACC_COMM_IF_PUTC (*xyz.__chan, (xyz.crc_mode ? 'C' : NAK));
619 xyz.total_retries++;
620 ZM_DEBUG (zm_dprintf ("NAK (%d)\n", __LINE__));
621 }
622 if (stat < 0 && (!xyz.first_xmodem_packet || stat != xyzModem_timeout))
623 {
624 *err = stat;
625 xyz.len = -1;
626 return total;
627 }
628 }
629 /* Don't "read" data from the EOF protocol package */
630 if (!xyz.at_eof && xyz.len > 0)
631 {
632 len = xyz.len;
633 if (size < len)
634 len = size;
635 memcpy (buf, xyz.bufp, len);
636 size -= len;
637 buf += len;
638 total += len;
639 xyz.len -= len;
640 xyz.bufp += len;
641 }
642 }
643 return total;
644}
645
646void
647xyzModem_stream_close (int *err)
648{
649 ZM_DEBUG (zm_dprintf
650 ("xyzModem - %s mode, %d(SOH)/%d(STX)/%d(CAN) packets, %d retries\n",
651 xyz.crc_mode ? "CRC" : "Cksum", xyz.total_SOH, xyz.total_STX,
652 xyz.total_CAN, xyz.total_retries));
653 ZM_DEBUG (zm_flush ());
654}
655
656/* Need to be able to clean out the input buffer, so have to take the */
657/* getc */
658void
659xyzModem_stream_terminate (bool abort, int (*getc) (void))
660{
661 int c;
662
663 if (abort)
664 {
665 ZM_DEBUG (zm_dprintf ("!!!! TRANSFER ABORT !!!!\n"));
666 switch (xyz.mode)
667 {
668 case xyzModem_xmodem:
669 case xyzModem_ymodem:
670 /* The X/YMODEM Spec seems to suggest that multiple CAN followed by an equal */
671 /* number of Backspaces is a friendly way to get the other end to abort. */
672 CYGACC_COMM_IF_PUTC (*xyz.__chan, CAN);
673 CYGACC_COMM_IF_PUTC (*xyz.__chan, CAN);
674 CYGACC_COMM_IF_PUTC (*xyz.__chan, CAN);
675 CYGACC_COMM_IF_PUTC (*xyz.__chan, CAN);
676 CYGACC_COMM_IF_PUTC (*xyz.__chan, BSP);
677 CYGACC_COMM_IF_PUTC (*xyz.__chan, BSP);
678 CYGACC_COMM_IF_PUTC (*xyz.__chan, BSP);
679 CYGACC_COMM_IF_PUTC (*xyz.__chan, BSP);
680 /* Now consume the rest of what's waiting on the line. */
681 ZM_DEBUG (zm_dprintf ("Flushing serial line.\n"));
682 xyzModem_flush ();
683 xyz.at_eof = true;
684 break;
685#ifdef xyzModem_zmodem
686 case xyzModem_zmodem:
687 /* Might support it some day I suppose. */
688#endif
689 break;
690 }
691 }
692 else
693 {
694 ZM_DEBUG (zm_dprintf ("Engaging cleanup mode...\n"));
695 /*
696 * Consume any trailing crap left in the inbuffer from
697 * previous received blocks. Since very few files are an exact multiple
698 * of the transfer block size, there will almost always be some gunk here.
699 * If we don't eat it now, RedBoot will think the user typed it.
700 */
701 ZM_DEBUG (zm_dprintf ("Trailing gunk:\n"));
702 while ((c = (*getc) ()) > -1)
703 ;
704 ZM_DEBUG (zm_dprintf ("\n"));
705 /*
706 * Make a small delay to give terminal programs like minicom
707 * time to get control again after their file transfer program
708 * exits.
709 */
710 CYGACC_CALL_IF_DELAY_US ((cyg_int32) 250000);
711 }
712}
713
714char *
715xyzModem_error (int err)
716{
717 switch (err)
718 {
719 case xyzModem_access:
720 return "Can't access file";
721 break;
722 case xyzModem_noZmodem:
723 return "Sorry, zModem not available yet";
724 break;
725 case xyzModem_timeout:
726 return "Timed out";
727 break;
728 case xyzModem_eof:
729 return "End of file";
730 break;
731 case xyzModem_cancel:
732 return "Cancelled";
733 break;
734 case xyzModem_frame:
735 return "Invalid framing";
736 break;
737 case xyzModem_cksum:
738 return "CRC/checksum error";
739 break;
740 case xyzModem_sequence:
741 return "Block sequence error";
742 break;
743 default:
744 return "Unknown error";
745 break;
746 }
747}
748
749/*
750 * RedBoot interface
751 */