// SPDX-License-Identifier: eCos-2.0 /* *========================================================================== * * xyzModem.c * * RedBoot stream handler for xyzModem protocol * *========================================================================== *#####DESCRIPTIONBEGIN#### * * Author(s): gthomas * Contributors: gthomas, tsmith, Yoshinori Sato * Date: 2000-07-14 * Purpose: * Description: * * This code is part of RedBoot (tm). * *####DESCRIPTIONEND#### * *========================================================================== */ #include #include #include #include #include /* Assumption - run xyzModem protocol over the console port */ /* Values magic to the protocol */ #define SOH 0x01 #define STX 0x02 #define EOT 0x04 #define ACK 0x06 #define BSP 0x08 #define NAK 0x15 #define CAN 0x18 #define EOF 0x1A /* ^Z for DOS officionados */ /* Data & state local to the protocol */ static struct { int *__chan; unsigned char pkt[1024], *bufp; unsigned char blk, cblk, crc1, crc2; unsigned char next_blk; /* Expected block */ int len, mode, total_retries; int total_SOH, total_STX, total_CAN; bool crc_mode, at_eof, tx_ack; unsigned long file_length, read_length; } xyz; #define xyzModem_CHAR_TIMEOUT 2000 /* 2 seconds */ #define xyzModem_MAX_RETRIES 20 #define xyzModem_MAX_RETRIES_WITH_CRC 10 #define xyzModem_CAN_COUNT 3 /* Wait for 3 CAN before quitting */ typedef int cyg_int32; static int CYGACC_COMM_IF_GETC_TIMEOUT (char chan, char *c) { ulong now = get_timer(0); WATCHDOG_RESET(); while (!tstc ()) { if (get_timer(now) > xyzModem_CHAR_TIMEOUT) break; } if (tstc ()) { *c = getc (); return 1; } return 0; } static void CYGACC_COMM_IF_PUTC (char x, char y) { putc (y); } /* Validate a hex character */ __inline__ static bool _is_hex (char c) { return (((c >= '0') && (c <= '9')) || ((c >= 'A') && (c <= 'F')) || ((c >= 'a') && (c <= 'f'))); } /* Convert a single hex nibble */ __inline__ static int _from_hex (char c) { int ret = 0; if ((c >= '0') && (c <= '9')) { ret = (c - '0'); } else if ((c >= 'a') && (c <= 'f')) { ret = (c - 'a' + 0x0a); } else if ((c >= 'A') && (c <= 'F')) { ret = (c - 'A' + 0x0A); } return ret; } /* Convert a character to lower case */ __inline__ static char _tolower (char c) { if ((c >= 'A') && (c <= 'Z')) { c = (c - 'A') + 'a'; } return c; } /* Parse (scan) a number */ static bool parse_num (char *s, unsigned long *val, char **es, char *delim) { bool first = true; int radix = 10; char c; unsigned long result = 0; int digit; while (*s == ' ') s++; while (*s) { if (first && (s[0] == '0') && (_tolower (s[1]) == 'x')) { radix = 16; s += 2; } first = false; c = *s++; if (_is_hex (c) && ((digit = _from_hex (c)) < radix)) { /* Valid digit */ result = (result * radix) + digit; } else { if (delim != (char *) 0) { /* See if this character is one of the delimiters */ char *dp = delim; while (*dp && (c != *dp)) dp++; if (*dp) break; /* Found a good delimiter */ } return false; /* Malformatted number */ } } *val = result; if (es != (char **) 0) { *es = s; } return true; } #if defined(DEBUG) && !CONFIG_IS_ENABLED(USE_TINY_PRINTF) /* * Note: this debug setup works by storing the strings in a fixed buffer */ static char zm_debug_buf[8192]; static char *zm_out = zm_debug_buf; static char *zm_out_start = zm_debug_buf; static int zm_dprintf(char *fmt, ...) { int len; va_list args; va_start(args, fmt); len = diag_vsprintf(zm_out, fmt, args); va_end(args); zm_out += len; return len; } static void zm_flush (void) { zm_out = zm_out_start; } static void zm_dump_buf (void *buf, int len) { } static unsigned char zm_buf[2048]; static unsigned char *zm_bp; static void zm_new (void) { zm_bp = zm_buf; } static void zm_save (unsigned char c) { *zm_bp++ = c; } static void zm_dump (int line) { zm_dprintf ("Packet at line: %d\n", line); zm_dump_buf (zm_buf, zm_bp - zm_buf); } #define ZM_DEBUG(x) x #else #define ZM_DEBUG(x) #endif /* Wait for the line to go idle */ static void xyzModem_flush (void) { int res; char c; while (true) { res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, &c); if (!res) return; } } static int xyzModem_get_hdr (void) { char c; int res; bool hdr_found = false; int i, can_total, hdr_chars; unsigned short cksum; ZM_DEBUG (zm_new ()); /* Find the start of a header */ can_total = 0; hdr_chars = 0; if (xyz.tx_ack) { CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK); xyz.tx_ack = false; } while (!hdr_found) { res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, &c); ZM_DEBUG (zm_save (c)); if (res) { hdr_chars++; switch (c) { case SOH: xyz.total_SOH++; case STX: if (c == STX) xyz.total_STX++; hdr_found = true; break; case CAN: xyz.total_CAN++; ZM_DEBUG (zm_dump (__LINE__)); if (++can_total == xyzModem_CAN_COUNT) { return xyzModem_cancel; } else { /* Wait for multiple CAN to avoid early quits */ break; } case EOT: /* EOT only supported if no noise */ if (hdr_chars == 1) { CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK); ZM_DEBUG (zm_dprintf ("ACK on EOT #%d\n", __LINE__)); ZM_DEBUG (zm_dump (__LINE__)); return xyzModem_eof; } default: /* Ignore, waiting for start of header */ ; } } else { /* Data stream timed out */ xyzModem_flush (); /* Toss any current input */ ZM_DEBUG (zm_dump (__LINE__)); CYGACC_CALL_IF_DELAY_US ((cyg_int32) 250000); return xyzModem_timeout; } } /* Header found, now read the data */ res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, (char *) &xyz.blk); ZM_DEBUG (zm_save (xyz.blk)); if (!res) { ZM_DEBUG (zm_dump (__LINE__)); return xyzModem_timeout; } res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, (char *) &xyz.cblk); ZM_DEBUG (zm_save (xyz.cblk)); if (!res) { ZM_DEBUG (zm_dump (__LINE__)); return xyzModem_timeout; } xyz.len = (c == SOH) ? 128 : 1024; xyz.bufp = xyz.pkt; for (i = 0; i < xyz.len; i++) { res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, &c); ZM_DEBUG (zm_save (c)); if (res) { xyz.pkt[i] = c; } else { ZM_DEBUG (zm_dump (__LINE__)); return xyzModem_timeout; } } res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, (char *) &xyz.crc1); ZM_DEBUG (zm_save (xyz.crc1)); if (!res) { ZM_DEBUG (zm_dump (__LINE__)); return xyzModem_timeout; } if (xyz.crc_mode) { res = CYGACC_COMM_IF_GETC_TIMEOUT (*xyz.__chan, (char *) &xyz.crc2); ZM_DEBUG (zm_save (xyz.crc2)); if (!res) { ZM_DEBUG (zm_dump (__LINE__)); return xyzModem_timeout; } } ZM_DEBUG (zm_dump (__LINE__)); /* Validate the message */ if ((xyz.blk ^ xyz.cblk) != (unsigned char) 0xFF) { ZM_DEBUG (zm_dprintf ("Framing error - blk: %x/%x/%x\n", xyz.blk, xyz.cblk, (xyz.blk ^ xyz.cblk))); ZM_DEBUG (zm_dump_buf (xyz.pkt, xyz.len)); xyzModem_flush (); return xyzModem_frame; } /* Verify checksum/CRC */ if (xyz.crc_mode) { cksum = crc16_ccitt(0, xyz.pkt, xyz.len); if (cksum != ((xyz.crc1 << 8) | xyz.crc2)) { ZM_DEBUG (zm_dprintf ("CRC error - recvd: %02x%02x, computed: %x\n", xyz.crc1, xyz.crc2, cksum & 0xFFFF)); return xyzModem_cksum; } } else { cksum = 0; for (i = 0; i < xyz.len; i++) { cksum += xyz.pkt[i]; } if (xyz.crc1 != (cksum & 0xFF)) { ZM_DEBUG (zm_dprintf ("Checksum error - recvd: %x, computed: %x\n", xyz.crc1, cksum & 0xFF)); return xyzModem_cksum; } } /* If we get here, the message passes [structural] muster */ return 0; } int xyzModem_stream_open (connection_info_t * info, int *err) { int stat = 0; int retries = xyzModem_MAX_RETRIES; int crc_retries = xyzModem_MAX_RETRIES_WITH_CRC; /* ZM_DEBUG(zm_out = zm_out_start); */ #ifdef xyzModem_zmodem if (info->mode == xyzModem_zmodem) { *err = xyzModem_noZmodem; return -1; } #endif /* TODO: CHECK ! */ int dummy = 0; xyz.__chan = &dummy; xyz.len = 0; xyz.crc_mode = true; xyz.at_eof = false; xyz.tx_ack = false; xyz.mode = info->mode; xyz.total_retries = 0; xyz.total_SOH = 0; xyz.total_STX = 0; xyz.total_CAN = 0; xyz.read_length = 0; xyz.file_length = 0; CYGACC_COMM_IF_PUTC (*xyz.__chan, (xyz.crc_mode ? 'C' : NAK)); if (xyz.mode == xyzModem_xmodem) { /* X-modem doesn't have an information header - exit here */ xyz.next_blk = 1; return 0; } while (retries-- > 0) { stat = xyzModem_get_hdr (); if (stat == 0) { /* Y-modem file information header */ if (xyz.blk == 0) { /* skip filename */ while (*xyz.bufp++); /* get the length */ parse_num ((char *) xyz.bufp, &xyz.file_length, NULL, " "); /* The rest of the file name data block quietly discarded */ xyz.tx_ack = true; } xyz.next_blk = 1; xyz.len = 0; return 0; } else if (stat == xyzModem_timeout) { if (--crc_retries <= 0) xyz.crc_mode = false; CYGACC_CALL_IF_DELAY_US (5 * 100000); /* Extra delay for startup */ CYGACC_COMM_IF_PUTC (*xyz.__chan, (xyz.crc_mode ? 'C' : NAK)); xyz.total_retries++; ZM_DEBUG (zm_dprintf ("NAK (%d)\n", __LINE__)); } if (stat == xyzModem_cancel) { break; } } *err = stat; ZM_DEBUG (zm_flush ()); return -1; } int xyzModem_stream_read (char *buf, int size, int *err) { int stat, total, len; int retries; total = 0; stat = xyzModem_cancel; /* Try and get 'size' bytes into the buffer */ while (!xyz.at_eof && (size > 0)) { if (xyz.len == 0) { retries = xyzModem_MAX_RETRIES; while (retries-- > 0) { stat = xyzModem_get_hdr (); if (stat == 0) { if (xyz.blk == xyz.next_blk) { xyz.tx_ack = true; ZM_DEBUG (zm_dprintf ("ACK block %d (%d)\n", xyz.blk, __LINE__)); xyz.next_blk = (xyz.next_blk + 1) & 0xFF; if (xyz.mode == xyzModem_xmodem || xyz.file_length == 0) { /* Data blocks can be padded with ^Z (EOF) characters */ /* This code tries to detect and remove them */ if ((xyz.bufp[xyz.len - 1] == EOF) && (xyz.bufp[xyz.len - 2] == EOF) && (xyz.bufp[xyz.len - 3] == EOF)) { while (xyz.len && (xyz.bufp[xyz.len - 1] == EOF)) { xyz.len--; } } } /* * See if accumulated length exceeds that of the file. * If so, reduce size (i.e., cut out pad bytes) * Only do this for Y-modem (and Z-modem should it ever * be supported since it can fall back to Y-modem mode). */ if (xyz.mode != xyzModem_xmodem && 0 != xyz.file_length) { xyz.read_length += xyz.len; if (xyz.read_length > xyz.file_length) { xyz.len -= (xyz.read_length - xyz.file_length); } } break; } else if (xyz.blk == ((xyz.next_blk - 1) & 0xFF)) { /* Just re-ACK this so sender will get on with it */ CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK); continue; /* Need new header */ } else { stat = xyzModem_sequence; } } if (stat == xyzModem_cancel) { break; } if (stat == xyzModem_eof) { CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK); ZM_DEBUG (zm_dprintf ("ACK (%d)\n", __LINE__)); if (xyz.mode == xyzModem_ymodem) { CYGACC_COMM_IF_PUTC (*xyz.__chan, (xyz.crc_mode ? 'C' : NAK)); xyz.total_retries++; ZM_DEBUG (zm_dprintf ("Reading Final Header\n")); stat = xyzModem_get_hdr (); CYGACC_COMM_IF_PUTC (*xyz.__chan, ACK); ZM_DEBUG (zm_dprintf ("FINAL ACK (%d)\n", __LINE__)); } xyz.at_eof = true; break; } CYGACC_COMM_IF_PUTC (*xyz.__chan, (xyz.crc_mode ? 'C' : NAK)); xyz.total_retries++; ZM_DEBUG (zm_dprintf ("NAK (%d)\n", __LINE__)); } if (stat < 0) { *err = stat; xyz.len = -1; return total; } } /* Don't "read" data from the EOF protocol package */ if (!xyz.at_eof) { len = xyz.len; if (size < len) len = size; memcpy (buf, xyz.bufp, len); size -= len; buf += len; total += len; xyz.len -= len; xyz.bufp += len; } } return total; } void xyzModem_stream_close (int *err) { diag_printf ("xyzModem - %s mode, %d(SOH)/%d(STX)/%d(CAN) packets, %d retries\n", xyz.crc_mode ? "CRC" : "Cksum", xyz.total_SOH, xyz.total_STX, xyz.total_CAN, xyz.total_retries); ZM_DEBUG (zm_flush ()); } /* Need to be able to clean out the input buffer, so have to take the */ /* getc */ void xyzModem_stream_terminate (bool abort, int (*getc) (void)) { int c; if (abort) { ZM_DEBUG (zm_dprintf ("!!!! TRANSFER ABORT !!!!\n")); switch (xyz.mode) { case xyzModem_xmodem: case xyzModem_ymodem: /* The X/YMODEM Spec seems to suggest that multiple CAN followed by an equal */ /* number of Backspaces is a friendly way to get the other end to abort. */ CYGACC_COMM_IF_PUTC (*xyz.__chan, CAN); CYGACC_COMM_IF_PUTC (*xyz.__chan, CAN); CYGACC_COMM_IF_PUTC (*xyz.__chan, CAN); CYGACC_COMM_IF_PUTC (*xyz.__chan, CAN); CYGACC_COMM_IF_PUTC (*xyz.__chan, BSP); CYGACC_COMM_IF_PUTC (*xyz.__chan, BSP); CYGACC_COMM_IF_PUTC (*xyz.__chan, BSP); CYGACC_COMM_IF_PUTC (*xyz.__chan, BSP); /* Now consume the rest of what's waiting on the line. */ ZM_DEBUG (zm_dprintf ("Flushing serial line.\n")); xyzModem_flush (); xyz.at_eof = true; break; #ifdef xyzModem_zmodem case xyzModem_zmodem: /* Might support it some day I suppose. */ #endif break; } } else { ZM_DEBUG (zm_dprintf ("Engaging cleanup mode...\n")); /* * Consume any trailing crap left in the inbuffer from * previous received blocks. Since very few files are an exact multiple * of the transfer block size, there will almost always be some gunk here. * If we don't eat it now, RedBoot will think the user typed it. */ ZM_DEBUG (zm_dprintf ("Trailing gunk:\n")); while ((c = (*getc) ()) > -1) ; ZM_DEBUG (zm_dprintf ("\n")); /* * Make a small delay to give terminal programs like minicom * time to get control again after their file transfer program * exits. */ CYGACC_CALL_IF_DELAY_US ((cyg_int32) 250000); } } char * xyzModem_error (int err) { switch (err) { case xyzModem_access: return "Can't access file"; break; case xyzModem_noZmodem: return "Sorry, zModem not available yet"; break; case xyzModem_timeout: return "Timed out"; break; case xyzModem_eof: return "End of file"; break; case xyzModem_cancel: return "Cancelled"; break; case xyzModem_frame: return "Invalid framing"; break; case xyzModem_cksum: return "CRC/checksum error"; break; case xyzModem_sequence: return "Block sequence error"; break; default: return "Unknown error"; break; } } /* * RedBoot interface */