Bernhard Reutner-Fischer | c2cb0f3 | 2006-04-13 12:45:04 +0000 | [diff] [blame] | 1 | /* vi: set sw=4 ts=4: */ |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 2 | /*------------------------------------------------------------------------- |
| 3 | * Filename: xmodem.c |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 4 | * Copyright: Copyright (C) 2001, Hewlett-Packard Company |
| 5 | * Author: Christopher Hoover <ch@hpl.hp.com> |
Eric Andersen | c7bda1c | 2004-03-15 08:29:22 +0000 | [diff] [blame] | 6 | * Description: xmodem functionality for uploading of kernels |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 7 | * and the like |
| 8 | * Created at: Thu Dec 20 01:58:08 PST 2001 |
| 9 | *-----------------------------------------------------------------------*/ |
| 10 | /* |
Eric Andersen | c7bda1c | 2004-03-15 08:29:22 +0000 | [diff] [blame] | 11 | * xmodem.c: xmodem functionality for uploading of kernels and |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 12 | * the like |
| 13 | * |
| 14 | * Copyright (C) 2001 Hewlett-Packard Laboratories |
| 15 | * |
Bernhard Reutner-Fischer | 20f4000 | 2006-01-30 17:17:14 +0000 | [diff] [blame] | 16 | * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 17 | * |
| 18 | * This was originally written for blob and then adapted for busybox. |
| 19 | * |
| 20 | */ |
| 21 | |
Denis Vlasenko | b6adbf1 | 2007-05-26 19:00:18 +0000 | [diff] [blame] | 22 | #include "libbb.h" |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 23 | |
| 24 | #define SOH 0x01 |
| 25 | #define STX 0x02 |
| 26 | #define EOT 0x04 |
| 27 | #define ACK 0x06 |
| 28 | #define NAK 0x15 |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 29 | #define BS 0x08 |
| 30 | |
| 31 | /* |
| 32 | |
| 33 | Cf: |
| 34 | |
| 35 | http://www.textfiles.com/apple/xmodem |
| 36 | http://www.phys.washington.edu/~belonis/xmodem/docxmodem.txt |
| 37 | http://www.phys.washington.edu/~belonis/xmodem/docymodem.txt |
| 38 | http://www.phys.washington.edu/~belonis/xmodem/modmprot.col |
| 39 | |
| 40 | */ |
| 41 | |
| 42 | #define TIMEOUT 1 |
| 43 | #define TIMEOUT_LONG 10 |
| 44 | #define MAXERRORS 10 |
| 45 | |
Denis Vlasenko | 400d8bb | 2008-02-24 13:36:01 +0000 | [diff] [blame] | 46 | static int read_byte(int fd, unsigned timeout) |
Denis Vlasenko | ac678ec | 2007-04-16 22:32:04 +0000 | [diff] [blame] | 47 | { |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 48 | char buf[1]; |
| 49 | int n; |
| 50 | |
| 51 | alarm(timeout); |
| 52 | |
| 53 | n = read(fd, &buf, 1); |
| 54 | |
| 55 | alarm(0); |
| 56 | |
| 57 | if (n == 1) |
| 58 | return buf[0] & 0xff; |
| 59 | else |
| 60 | return -1; |
| 61 | } |
| 62 | |
| 63 | static int receive(char *error_buf, size_t error_buf_size, |
| 64 | int ttyfd, int filefd) |
| 65 | { |
| 66 | char blockBuf[1024]; |
| 67 | unsigned int errors = 0; |
| 68 | unsigned int wantBlockNo = 1; |
| 69 | unsigned int length = 0; |
| 70 | int docrc = 1; |
| 71 | char nak = 'C'; |
| 72 | unsigned int timeout = TIMEOUT_LONG; |
| 73 | |
| 74 | #define note_error(fmt,args...) \ |
| 75 | snprintf(error_buf, error_buf_size, fmt,##args) |
| 76 | |
Rob Landley | 399d45f | 2006-06-21 01:49:17 +0000 | [diff] [blame] | 77 | /* Flush pending input */ |
| 78 | tcflush(ttyfd, TCIFLUSH); |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 79 | |
| 80 | /* Ask for CRC; if we get errors, we will go with checksum */ |
Rob Landley | 399d45f | 2006-06-21 01:49:17 +0000 | [diff] [blame] | 81 | write(ttyfd, &nak, 1); |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 82 | |
| 83 | for (;;) { |
| 84 | int blockBegin; |
| 85 | int blockNo, blockNoOnesCompl; |
| 86 | int blockLength; |
| 87 | int cksum = 0; |
| 88 | int crcHi = 0; |
| 89 | int crcLo = 0; |
| 90 | |
| 91 | blockBegin = read_byte(ttyfd, timeout); |
| 92 | if (blockBegin < 0) |
| 93 | goto timeout; |
| 94 | |
| 95 | timeout = TIMEOUT; |
| 96 | nak = NAK; |
| 97 | |
| 98 | switch (blockBegin) { |
| 99 | case SOH: |
| 100 | case STX: |
| 101 | break; |
| 102 | |
| 103 | case EOT: |
Rob Landley | 399d45f | 2006-06-21 01:49:17 +0000 | [diff] [blame] | 104 | nak = ACK; |
| 105 | write(ttyfd, &nak, 1); |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 106 | goto done; |
| 107 | |
| 108 | default: |
| 109 | goto error; |
| 110 | } |
| 111 | |
| 112 | /* block no */ |
| 113 | blockNo = read_byte(ttyfd, TIMEOUT); |
| 114 | if (blockNo < 0) |
| 115 | goto timeout; |
| 116 | |
| 117 | /* block no one's compliment */ |
| 118 | blockNoOnesCompl = read_byte(ttyfd, TIMEOUT); |
| 119 | if (blockNoOnesCompl < 0) |
| 120 | goto timeout; |
| 121 | |
| 122 | if (blockNo != (255 - blockNoOnesCompl)) { |
| 123 | note_error("bad block ones compl"); |
| 124 | goto error; |
| 125 | } |
| 126 | |
| 127 | blockLength = (blockBegin == SOH) ? 128 : 1024; |
| 128 | |
| 129 | { |
| 130 | int i; |
| 131 | |
| 132 | for (i = 0; i < blockLength; i++) { |
| 133 | int cc = read_byte(ttyfd, TIMEOUT); |
| 134 | if (cc < 0) |
| 135 | goto timeout; |
| 136 | blockBuf[i] = cc; |
| 137 | } |
| 138 | } |
| 139 | |
| 140 | if (docrc) { |
| 141 | crcHi = read_byte(ttyfd, TIMEOUT); |
| 142 | if (crcHi < 0) |
| 143 | goto timeout; |
| 144 | |
| 145 | crcLo = read_byte(ttyfd, TIMEOUT); |
| 146 | if (crcLo < 0) |
| 147 | goto timeout; |
| 148 | } else { |
| 149 | cksum = read_byte(ttyfd, TIMEOUT); |
| 150 | if (cksum < 0) |
| 151 | goto timeout; |
| 152 | } |
| 153 | |
| 154 | if (blockNo == ((wantBlockNo - 1) & 0xff)) { |
| 155 | /* a repeat of the last block is ok, just ignore it. */ |
| 156 | /* this also ignores the initial block 0 which is */ |
| 157 | /* meta data. */ |
| 158 | goto next; |
| 159 | } else if (blockNo != (wantBlockNo & 0xff)) { |
| 160 | note_error("unexpected block no, 0x%08x, expecting 0x%08x", blockNo, wantBlockNo); |
| 161 | goto error; |
| 162 | } |
| 163 | |
| 164 | if (docrc) { |
| 165 | int crc = 0; |
| 166 | int i, j; |
| 167 | int expectedCrcHi; |
| 168 | int expectedCrcLo; |
| 169 | |
| 170 | for (i = 0; i < blockLength; i++) { |
| 171 | crc = crc ^ (int) blockBuf[i] << 8; |
| 172 | for (j = 0; j < 8; j++) |
| 173 | if (crc & 0x8000) |
| 174 | crc = crc << 1 ^ 0x1021; |
| 175 | else |
| 176 | crc = crc << 1; |
| 177 | } |
| 178 | |
| 179 | expectedCrcHi = (crc >> 8) & 0xff; |
| 180 | expectedCrcLo = crc & 0xff; |
| 181 | |
| 182 | if ((crcHi != expectedCrcHi) || |
| 183 | (crcLo != expectedCrcLo)) { |
| 184 | note_error("crc error, expected 0x%02x 0x%02x, got 0x%02x 0x%02x", expectedCrcHi, expectedCrcLo, crcHi, crcLo); |
| 185 | goto error; |
| 186 | } |
| 187 | } else { |
| 188 | unsigned char expectedCksum = 0; |
| 189 | int i; |
| 190 | |
| 191 | for (i = 0; i < blockLength; i++) |
| 192 | expectedCksum += blockBuf[i]; |
| 193 | |
| 194 | if (cksum != expectedCksum) { |
| 195 | note_error("checksum error, expected 0x%02x, got 0x%02x", expectedCksum, cksum); |
| 196 | goto error; |
| 197 | } |
| 198 | } |
| 199 | |
| 200 | wantBlockNo++; |
| 201 | length += blockLength; |
| 202 | |
Rob Landley | 5343747 | 2006-07-16 08:14:35 +0000 | [diff] [blame] | 203 | if (full_write(filefd, blockBuf, blockLength) < 0) { |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 204 | note_error("write to file failed: %m"); |
| 205 | goto fatal; |
| 206 | } |
| 207 | |
| 208 | next: |
| 209 | errors = 0; |
Rob Landley | 399d45f | 2006-06-21 01:49:17 +0000 | [diff] [blame] | 210 | nak = ACK; |
| 211 | write(ttyfd, &nak, 1); |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 212 | continue; |
| 213 | |
| 214 | error: |
| 215 | timeout: |
| 216 | errors++; |
| 217 | if (errors == MAXERRORS) { |
| 218 | /* Abort */ |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 219 | |
| 220 | // if using crc, try again w/o crc |
| 221 | if (nak == 'C') { |
| 222 | nak = NAK; |
| 223 | errors = 0; |
| 224 | docrc = 0; |
| 225 | goto timeout; |
| 226 | } |
| 227 | |
| 228 | note_error("too many errors; giving up"); |
| 229 | |
| 230 | fatal: |
Rob Landley | 399d45f | 2006-06-21 01:49:17 +0000 | [diff] [blame] | 231 | /* 5 CAN followed by 5 BS */ |
| 232 | write(ttyfd, "\030\030\030\030\030\010\010\010\010\010", 10); |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 233 | return -1; |
| 234 | } |
| 235 | |
Rob Landley | 399d45f | 2006-06-21 01:49:17 +0000 | [diff] [blame] | 236 | /* Flush pending input */ |
| 237 | tcflush(ttyfd, TCIFLUSH); |
| 238 | |
| 239 | write(ttyfd, &nak, 1); |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 240 | } |
| 241 | |
| 242 | done: |
| 243 | return length; |
| 244 | |
| 245 | #undef note_error |
| 246 | } |
| 247 | |
Bernhard Reutner-Fischer | 20f4000 | 2006-01-30 17:17:14 +0000 | [diff] [blame] | 248 | static void sigalrm_handler(int ATTRIBUTE_UNUSED signum) |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 249 | { |
| 250 | } |
| 251 | |
Denis Vlasenko | 9b49a5e | 2007-10-11 10:05:36 +0000 | [diff] [blame] | 252 | int rx_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 253 | int rx_main(int argc, char **argv) |
| 254 | { |
| 255 | char *fn; |
| 256 | int ttyfd, filefd; |
| 257 | struct termios tty, orig_tty; |
| 258 | struct sigaction act; |
| 259 | int n; |
| 260 | char error_buf[256]; |
| 261 | |
| 262 | if (argc != 2) |
| 263 | bb_show_usage(); |
| 264 | |
| 265 | fn = argv[1]; |
Bernhard Reutner-Fischer | 64d7e93 | 2006-09-11 16:01:40 +0000 | [diff] [blame] | 266 | ttyfd = xopen(CURRENT_TTY, O_RDWR); |
Denis Vlasenko | cf749bc | 2006-11-26 15:45:17 +0000 | [diff] [blame] | 267 | filefd = xopen(fn, O_RDWR|O_CREAT|O_TRUNC); |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 268 | |
| 269 | if (tcgetattr(ttyfd, &tty) < 0) |
Denis Vlasenko | 7d219aa | 2006-10-05 10:17:08 +0000 | [diff] [blame] | 270 | bb_perror_msg_and_die("tcgetattr"); |
Eric Andersen | c7bda1c | 2004-03-15 08:29:22 +0000 | [diff] [blame] | 271 | |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 272 | orig_tty = tty; |
| 273 | |
| 274 | cfmakeraw(&tty); |
| 275 | tcsetattr(ttyfd, TCSAFLUSH, &tty); |
Eric Andersen | c7bda1c | 2004-03-15 08:29:22 +0000 | [diff] [blame] | 276 | |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 277 | memset(&act, 0, sizeof(act)); |
| 278 | act.sa_handler = sigalrm_handler; |
| 279 | sigaction(SIGALRM, &act, 0); |
| 280 | |
| 281 | n = receive(error_buf, sizeof(error_buf), ttyfd, filefd); |
| 282 | |
| 283 | close(filefd); |
| 284 | |
| 285 | tcsetattr(ttyfd, TCSAFLUSH, &orig_tty); |
| 286 | |
| 287 | if (n < 0) |
Denis Vlasenko | 7d219aa | 2006-10-05 10:17:08 +0000 | [diff] [blame] | 288 | bb_error_msg_and_die("\nreceive failed:\n %s", error_buf); |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 289 | |
Denis Vlasenko | f0ed376 | 2006-10-26 23:21:47 +0000 | [diff] [blame] | 290 | fflush_stdout_and_exit(EXIT_SUCCESS); |
Glenn L McGrath | 8f3bc4c | 2003-12-20 07:30:35 +0000 | [diff] [blame] | 291 | } |