Contents of /tags/mkinitrd-6_3_0/busybox/loginutils/getty.c
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Thu Aug 19 10:14:02 2010 UTC (14 years, 1 month ago) by niro
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Thu Aug 19 10:14:02 2010 UTC (14 years, 1 month ago) by niro
File MIME type: text/plain
File size: 23189 byte(s)
tagged 'mkinitrd-6_3_0'
1 | /* vi: set sw=4 ts=4: */ |
2 | /* agetty.c - another getty program for Linux. By W. Z. Venema 1989 |
3 | * Ported to Linux by Peter Orbaek <poe@daimi.aau.dk> |
4 | * This program is freely distributable. The entire man-page used to |
5 | * be here. Now read the real man-page agetty.8 instead. |
6 | * |
7 | * option added by Eric Rasmussen <ear@usfirst.org> - 12/28/95 |
8 | * |
9 | * 1999-02-22 Arkadiusz Mickiewicz <misiek@misiek.eu.org> |
10 | * - added Native Language Support |
11 | * |
12 | * 1999-05-05 Thorsten Kranzkowski <dl8bcu@gmx.net> |
13 | * - enable hardware flow control before displaying /etc/issue |
14 | * |
15 | * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. |
16 | */ |
17 | |
18 | #include "libbb.h" |
19 | #include <syslog.h> |
20 | |
21 | #if ENABLE_FEATURE_UTMP |
22 | # include <utmp.h> /* LOGIN_PROCESS */ |
23 | #endif |
24 | |
25 | #ifndef IUCLC |
26 | # define IUCLC 0 |
27 | #endif |
28 | |
29 | /* |
30 | * Some heuristics to find out what environment we are in: if it is not |
31 | * System V, assume it is SunOS 4. |
32 | */ |
33 | #ifdef LOGIN_PROCESS /* defined in System V utmp.h */ |
34 | #include <sys/utsname.h> |
35 | #else /* if !sysV style, wtmp/utmp code is off */ |
36 | #undef ENABLE_FEATURE_UTMP |
37 | #undef ENABLE_FEATURE_WTMP |
38 | #define ENABLE_FEATURE_UTMP 0 |
39 | #define ENABLE_FEATURE_WTMP 0 |
40 | #endif /* LOGIN_PROCESS */ |
41 | |
42 | /* |
43 | * Things you may want to modify. |
44 | * |
45 | * You may disagree with the default line-editing etc. characters defined |
46 | * below. Note, however, that DEL cannot be used for interrupt generation |
47 | * and for line editing at the same time. |
48 | */ |
49 | |
50 | /* I doubt there are systems which still need this */ |
51 | #undef HANDLE_ALLCAPS |
52 | #undef ANCIENT_BS_KILL_CHARS |
53 | |
54 | #define _PATH_LOGIN "/bin/login" |
55 | |
56 | /* If ISSUE is not defined, getty will never display the contents of the |
57 | * /etc/issue file. You will not want to spit out large "issue" files at the |
58 | * wrong baud rate. |
59 | */ |
60 | #define ISSUE "/etc/issue" /* displayed before the login prompt */ |
61 | |
62 | /* Some shorthands for control characters. */ |
63 | #define CTL(x) ((x) ^ 0100) /* Assumes ASCII dialect */ |
64 | #define CR CTL('M') /* carriage return */ |
65 | #define NL CTL('J') /* line feed */ |
66 | #define BS CTL('H') /* back space */ |
67 | #define DEL CTL('?') /* delete */ |
68 | |
69 | /* Defaults for line-editing etc. characters; you may want to change this. */ |
70 | #define DEF_ERASE DEL /* default erase character */ |
71 | #define DEF_INTR CTL('C') /* default interrupt character */ |
72 | #define DEF_QUIT CTL('\\') /* default quit char */ |
73 | #define DEF_KILL CTL('U') /* default kill char */ |
74 | #define DEF_EOF CTL('D') /* default EOF char */ |
75 | #define DEF_EOL '\n' |
76 | #define DEF_SWITCH 0 /* default switch char */ |
77 | |
78 | /* |
79 | * When multiple baud rates are specified on the command line, the first one |
80 | * we will try is the first one specified. |
81 | */ |
82 | #define MAX_SPEED 10 /* max. nr. of baud rates */ |
83 | |
84 | /* Storage for command-line options. */ |
85 | struct options { |
86 | int flags; /* toggle switches, see below */ |
87 | unsigned timeout; /* time-out period */ |
88 | const char *login; /* login program */ |
89 | const char *tty; /* name of tty */ |
90 | const char *initstring; /* modem init string */ |
91 | const char *issue; /* alternative issue file */ |
92 | int numspeed; /* number of baud rates to try */ |
93 | int speeds[MAX_SPEED]; /* baud rates to be tried */ |
94 | }; |
95 | |
96 | /* Storage for things detected while the login name was read. */ |
97 | struct chardata { |
98 | unsigned char erase; /* erase character */ |
99 | unsigned char kill; /* kill character */ |
100 | unsigned char eol; /* end-of-line character */ |
101 | unsigned char parity; /* what parity did we see */ |
102 | /* (parity & 1): saw odd parity char with 7th bit set */ |
103 | /* (parity & 2): saw even parity char with 7th bit set */ |
104 | /* parity == 0: probably 7-bit, space parity? */ |
105 | /* parity == 1: probably 7-bit, odd parity? */ |
106 | /* parity == 2: probably 7-bit, even parity? */ |
107 | /* parity == 3: definitely 8 bit, no parity! */ |
108 | /* Hmm... with any value of "parity" 8 bit, no parity is possible */ |
109 | #ifdef HANDLE_ALLCAPS |
110 | unsigned char capslock; /* upper case without lower case */ |
111 | #endif |
112 | }; |
113 | |
114 | |
115 | /* Initial values for the above. */ |
116 | static const struct chardata init_chardata = { |
117 | DEF_ERASE, /* default erase character */ |
118 | DEF_KILL, /* default kill character */ |
119 | 13, /* default eol char */ |
120 | 0, /* space parity */ |
121 | #ifdef HANDLE_ALLCAPS |
122 | 0, /* no capslock */ |
123 | #endif |
124 | }; |
125 | |
126 | static const char opt_string[] ALIGN1 = "I:LH:f:hil:mt:wn"; |
127 | #define F_INITSTRING (1 << 0) /* -I initstring is set */ |
128 | #define F_LOCAL (1 << 1) /* -L force local */ |
129 | #define F_FAKEHOST (1 << 2) /* -H fake hostname */ |
130 | #define F_CUSTISSUE (1 << 3) /* -f give alternative issue file */ |
131 | #define F_RTSCTS (1 << 4) /* -h enable RTS/CTS flow control */ |
132 | #define F_ISSUE (1 << 5) /* -i display /etc/issue */ |
133 | #define F_LOGIN (1 << 6) /* -l non-default login program */ |
134 | #define F_PARSE (1 << 7) /* -m process modem status messages */ |
135 | #define F_TIMEOUT (1 << 8) /* -t time out */ |
136 | #define F_WAITCRLF (1 << 9) /* -w wait for CR or LF */ |
137 | #define F_NOPROMPT (1 << 10) /* -n don't ask for login name */ |
138 | |
139 | |
140 | #define line_buf bb_common_bufsiz1 |
141 | |
142 | /* The following is used for understandable diagnostics. */ |
143 | #ifdef DEBUGGING |
144 | static FILE *dbf; |
145 | #define DEBUGTERM "/dev/ttyp0" |
146 | #define debug(...) do { fprintf(dbf, __VA_ARGS__); fflush(dbf); } while (0) |
147 | #else |
148 | #define debug(...) ((void)0) |
149 | #endif |
150 | |
151 | |
152 | /* bcode - convert speed string to speed code; return <= 0 on failure */ |
153 | static int bcode(const char *s) |
154 | { |
155 | int value = bb_strtou(s, NULL, 10); /* yes, int is intended! */ |
156 | if (value < 0) /* bad terminating char, overflow, etc */ |
157 | return value; |
158 | return tty_value_to_baud(value); |
159 | } |
160 | |
161 | /* parse_speeds - parse alternate baud rates */ |
162 | static void parse_speeds(struct options *op, char *arg) |
163 | { |
164 | char *cp; |
165 | |
166 | /* NB: at least one iteration is always done */ |
167 | debug("entered parse_speeds\n"); |
168 | while ((cp = strsep(&arg, ",")) != NULL) { |
169 | op->speeds[op->numspeed] = bcode(cp); |
170 | if (op->speeds[op->numspeed] < 0) |
171 | bb_error_msg_and_die("bad speed: %s", cp); |
172 | /* note: arg "0" turns into speed B0 */ |
173 | op->numspeed++; |
174 | if (op->numspeed > MAX_SPEED) |
175 | bb_error_msg_and_die("too many alternate speeds"); |
176 | } |
177 | debug("exiting parse_speeds\n"); |
178 | } |
179 | |
180 | /* parse_args - parse command-line arguments */ |
181 | static void parse_args(char **argv, struct options *op, char **fakehost_p) |
182 | { |
183 | char *ts; |
184 | |
185 | opt_complementary = "-2:t+"; /* at least 2 args; -t N */ |
186 | op->flags = getopt32(argv, opt_string, |
187 | &(op->initstring), fakehost_p, &(op->issue), |
188 | &(op->login), &op->timeout); |
189 | argv += optind; |
190 | if (op->flags & F_INITSTRING) { |
191 | const char *p = op->initstring; |
192 | char *q; |
193 | |
194 | op->initstring = q = xstrdup(p); |
195 | /* copy optarg into op->initstring decoding \ddd |
196 | octal codes into chars */ |
197 | while (*p) { |
198 | if (*p == '\\') { |
199 | p++; |
200 | *q++ = bb_process_escape_sequence(&p); |
201 | } else { |
202 | *q++ = *p++; |
203 | } |
204 | } |
205 | *q = '\0'; |
206 | } |
207 | op->flags ^= F_ISSUE; /* invert flag "show /etc/issue" */ |
208 | debug("after getopt\n"); |
209 | |
210 | /* we loosen up a bit and accept both "baudrate tty" and "tty baudrate" */ |
211 | op->tty = argv[0]; /* tty name */ |
212 | ts = argv[1]; /* baud rate(s) */ |
213 | if (isdigit(argv[0][0])) { |
214 | /* a number first, assume it's a speed (BSD style) */ |
215 | op->tty = ts; /* tty name is in argv[1] */ |
216 | ts = argv[0]; /* baud rate(s) */ |
217 | } |
218 | parse_speeds(op, ts); |
219 | |
220 | // TODO: if applet_name is set to "getty: TTY", bb_error_msg's get simpler! |
221 | // grep for "%s:" |
222 | |
223 | if (argv[2]) |
224 | xsetenv("TERM", argv[2]); |
225 | |
226 | debug("exiting parse_args\n"); |
227 | } |
228 | |
229 | /* open_tty - set up tty as standard { input, output, error } */ |
230 | static void open_tty(const char *tty) |
231 | { |
232 | /* Set up new standard input, unless we are given an already opened port. */ |
233 | if (NOT_LONE_DASH(tty)) { |
234 | // struct stat st; |
235 | // int cur_dir_fd; |
236 | // int fd; |
237 | |
238 | /* Sanity checks... */ |
239 | // cur_dir_fd = xopen(".", O_DIRECTORY | O_NONBLOCK); |
240 | // xchdir("/dev"); |
241 | // xstat(tty, &st); |
242 | // if (!S_ISCHR(st.st_mode)) |
243 | // bb_error_msg_and_die("%s: not a character device", tty); |
244 | |
245 | if (tty[0] != '/') |
246 | tty = xasprintf("/dev/%s", tty); /* will leak it */ |
247 | |
248 | /* Open the tty as standard input. */ |
249 | debug("open(2)\n"); |
250 | close(0); |
251 | /*fd =*/ xopen(tty, O_RDWR | O_NONBLOCK); /* uses fd 0 */ |
252 | |
253 | // /* Restore current directory */ |
254 | // fchdir(cur_dir_fd); |
255 | |
256 | /* Open the tty as standard input, continued */ |
257 | // xmove_fd(fd, 0); |
258 | // /* fd is >= cur_dir_fd, and cur_dir_fd gets closed too here: */ |
259 | // while (fd > 2) |
260 | // close(fd--); |
261 | |
262 | /* Set proper protections and ownership. */ |
263 | fchown(0, 0, 0); /* 0:0 */ |
264 | fchmod(0, 0620); /* crw--w---- */ |
265 | } else { |
266 | /* |
267 | * Standard input should already be connected to an open port. Make |
268 | * sure it is open for read/write. |
269 | */ |
270 | if ((fcntl(0, F_GETFL) & O_RDWR) != O_RDWR) |
271 | bb_error_msg_and_die("stdin is not open for read/write"); |
272 | } |
273 | } |
274 | |
275 | /* termios_init - initialize termios settings */ |
276 | static void termios_init(struct termios *tp, int speed, struct options *op) |
277 | { |
278 | speed_t ispeed, ospeed; |
279 | /* |
280 | * Initial termios settings: 8-bit characters, raw-mode, blocking i/o. |
281 | * Special characters are set after we have read the login name; all |
282 | * reads will be done in raw mode anyway. Errors will be dealt with |
283 | * later on. |
284 | */ |
285 | #ifdef __linux__ |
286 | /* flush input and output queues, important for modems! */ |
287 | ioctl(0, TCFLSH, TCIOFLUSH); /* tcflush(0, TCIOFLUSH)? - same */ |
288 | #endif |
289 | ispeed = ospeed = speed; |
290 | if (speed == B0) { |
291 | /* Speed was specified as "0" on command line. |
292 | * Just leave it unchanged */ |
293 | ispeed = cfgetispeed(tp); |
294 | ospeed = cfgetospeed(tp); |
295 | } |
296 | tp->c_cflag = CS8 | HUPCL | CREAD; |
297 | if (op->flags & F_LOCAL) |
298 | tp->c_cflag |= CLOCAL; |
299 | cfsetispeed(tp, ispeed); |
300 | cfsetospeed(tp, ospeed); |
301 | |
302 | tp->c_iflag = tp->c_lflag = tp->c_line = 0; |
303 | tp->c_oflag = OPOST | ONLCR; |
304 | tp->c_cc[VMIN] = 1; |
305 | tp->c_cc[VTIME] = 0; |
306 | |
307 | /* Optionally enable hardware flow control */ |
308 | #ifdef CRTSCTS |
309 | if (op->flags & F_RTSCTS) |
310 | tp->c_cflag |= CRTSCTS; |
311 | #endif |
312 | |
313 | tcsetattr_stdin_TCSANOW(tp); |
314 | |
315 | debug("term_io 2\n"); |
316 | } |
317 | |
318 | /* auto_baud - extract baud rate from modem status message */ |
319 | static void auto_baud(char *buf, unsigned size_buf, struct termios *tp) |
320 | { |
321 | int speed; |
322 | int vmin; |
323 | unsigned iflag; |
324 | char *bp; |
325 | int nread; |
326 | |
327 | /* |
328 | * This works only if the modem produces its status code AFTER raising |
329 | * the DCD line, and if the computer is fast enough to set the proper |
330 | * baud rate before the message has gone by. We expect a message of the |
331 | * following format: |
332 | * |
333 | * <junk><number><junk> |
334 | * |
335 | * The number is interpreted as the baud rate of the incoming call. If the |
336 | * modem does not tell us the baud rate within one second, we will keep |
337 | * using the current baud rate. It is advisable to enable BREAK |
338 | * processing (comma-separated list of baud rates) if the processing of |
339 | * modem status messages is enabled. |
340 | */ |
341 | |
342 | /* |
343 | * Use 7-bit characters, don't block if input queue is empty. Errors will |
344 | * be dealt with later on. |
345 | */ |
346 | iflag = tp->c_iflag; |
347 | tp->c_iflag |= ISTRIP; /* enable 8th-bit stripping */ |
348 | vmin = tp->c_cc[VMIN]; |
349 | tp->c_cc[VMIN] = 0; /* don't block if queue empty */ |
350 | tcsetattr_stdin_TCSANOW(tp); |
351 | |
352 | /* |
353 | * Wait for a while, then read everything the modem has said so far and |
354 | * try to extract the speed of the dial-in call. |
355 | */ |
356 | sleep(1); |
357 | nread = safe_read(STDIN_FILENO, buf, size_buf - 1); |
358 | if (nread > 0) { |
359 | buf[nread] = '\0'; |
360 | for (bp = buf; bp < buf + nread; bp++) { |
361 | if (isdigit(*bp)) { |
362 | speed = bcode(bp); |
363 | if (speed > 0) { |
364 | tp->c_cflag &= ~CBAUD; |
365 | tp->c_cflag |= speed; |
366 | } |
367 | break; |
368 | } |
369 | } |
370 | } |
371 | |
372 | /* Restore terminal settings. Errors will be dealt with later on. */ |
373 | tp->c_iflag = iflag; |
374 | tp->c_cc[VMIN] = vmin; |
375 | tcsetattr_stdin_TCSANOW(tp); |
376 | } |
377 | |
378 | /* do_prompt - show login prompt, optionally preceded by /etc/issue contents */ |
379 | static void do_prompt(struct options *op) |
380 | { |
381 | #ifdef ISSUE |
382 | print_login_issue(op->issue, op->tty); |
383 | #endif |
384 | print_login_prompt(); |
385 | } |
386 | |
387 | #ifdef HANDLE_ALLCAPS |
388 | /* all_is_upcase - string contains upper case without lower case */ |
389 | /* returns 1 if true, 0 if false */ |
390 | static int all_is_upcase(const char *s) |
391 | { |
392 | while (*s) |
393 | if (islower(*s++)) |
394 | return 0; |
395 | return 1; |
396 | } |
397 | #endif |
398 | |
399 | /* get_logname - get user name, establish parity, speed, erase, kill, eol; |
400 | * return NULL on BREAK, logname on success */ |
401 | static char *get_logname(char *logname, unsigned size_logname, |
402 | struct options *op, struct chardata *cp) |
403 | { |
404 | char *bp; |
405 | char c; /* input character, full eight bits */ |
406 | char ascval; /* low 7 bits of input character */ |
407 | int bits; /* # of "1" bits per character */ |
408 | int mask; /* mask with 1 bit up */ |
409 | static const char erase[][3] = {/* backspace-space-backspace */ |
410 | "\010\040\010", /* space parity */ |
411 | "\010\040\010", /* odd parity */ |
412 | "\210\240\210", /* even parity */ |
413 | "\010\040\010", /* 8 bit no parity */ |
414 | }; |
415 | |
416 | /* NB: *cp is pre-initialized with init_chardata */ |
417 | |
418 | /* Flush pending input (esp. after parsing or switching the baud rate). */ |
419 | sleep(1); |
420 | ioctl(0, TCFLSH, TCIFLUSH); /* tcflush(0, TCIOFLUSH)? - same */ |
421 | |
422 | /* Prompt for and read a login name. */ |
423 | logname[0] = '\0'; |
424 | while (!logname[0]) { |
425 | /* Write issue file and prompt, with "parity" bit == 0. */ |
426 | do_prompt(op); |
427 | |
428 | /* Read name, watch for break, parity, erase, kill, end-of-line. */ |
429 | bp = logname; |
430 | cp->eol = '\0'; |
431 | while (cp->eol == '\0') { |
432 | |
433 | /* Do not report trivial EINTR/EIO errors. */ |
434 | errno = EINTR; /* make read of 0 bytes be silent too */ |
435 | if (read(STDIN_FILENO, &c, 1) < 1) { |
436 | if (errno == EINTR || errno == EIO) |
437 | exit(EXIT_SUCCESS); |
438 | bb_perror_msg_and_die("%s: read", op->tty); |
439 | } |
440 | |
441 | /* BREAK. If we have speeds to try, |
442 | * return NULL (will switch speeds and return here) */ |
443 | if (c == '\0' && op->numspeed > 1) |
444 | return NULL; |
445 | |
446 | /* Do parity bit handling. */ |
447 | if (!(op->flags & F_LOCAL) && (c & 0x80)) { /* "parity" bit on? */ |
448 | bits = 1; |
449 | mask = 1; |
450 | while (mask & 0x7f) { |
451 | if (mask & c) |
452 | bits++; /* count "1" bits */ |
453 | mask <<= 1; |
454 | } |
455 | /* ... |= 2 - even, 1 - odd */ |
456 | cp->parity |= 2 - (bits & 1); |
457 | } |
458 | |
459 | /* Do erase, kill and end-of-line processing. */ |
460 | ascval = c & 0x7f; |
461 | switch (ascval) { |
462 | case CR: |
463 | case NL: |
464 | *bp = '\0'; /* terminate logname */ |
465 | cp->eol = ascval; /* set end-of-line char */ |
466 | break; |
467 | case BS: |
468 | case DEL: |
469 | #ifdef ANCIENT_BS_KILL_CHARS |
470 | case '#': |
471 | #endif |
472 | cp->erase = ascval; /* set erase character */ |
473 | if (bp > logname) { |
474 | full_write(STDOUT_FILENO, erase[cp->parity], 3); |
475 | bp--; |
476 | } |
477 | break; |
478 | case CTL('U'): |
479 | #ifdef ANCIENT_BS_KILL_CHARS |
480 | case '@': |
481 | #endif |
482 | cp->kill = ascval; /* set kill character */ |
483 | while (bp > logname) { |
484 | full_write(STDOUT_FILENO, erase[cp->parity], 3); |
485 | bp--; |
486 | } |
487 | break; |
488 | case CTL('D'): |
489 | exit(EXIT_SUCCESS); |
490 | default: |
491 | if (ascval < ' ') { |
492 | /* ignore garbage characters */ |
493 | } else if ((int)(bp - logname) >= size_logname - 1) { |
494 | bb_error_msg_and_die("%s: input overrun", op->tty); |
495 | } else { |
496 | full_write(STDOUT_FILENO, &c, 1); /* echo the character */ |
497 | *bp++ = ascval; /* and store it */ |
498 | } |
499 | break; |
500 | } |
501 | } |
502 | } |
503 | /* Handle names with upper case and no lower case. */ |
504 | |
505 | #ifdef HANDLE_ALLCAPS |
506 | cp->capslock = all_is_upcase(logname); |
507 | if (cp->capslock) { |
508 | for (bp = logname; *bp; bp++) |
509 | if (isupper(*bp)) |
510 | *bp = tolower(*bp); /* map name to lower case */ |
511 | } |
512 | #endif |
513 | return logname; |
514 | } |
515 | |
516 | /* termios_final - set the final tty mode bits */ |
517 | static void termios_final(struct options *op, struct termios *tp, struct chardata *cp) |
518 | { |
519 | /* General terminal-independent stuff. */ |
520 | tp->c_iflag |= IXON | IXOFF; /* 2-way flow control */ |
521 | tp->c_lflag |= ICANON | ISIG | ECHO | ECHOE | ECHOK | ECHOKE; |
522 | /* no longer| ECHOCTL | ECHOPRT */ |
523 | tp->c_oflag |= OPOST; |
524 | /* tp->c_cflag = 0; */ |
525 | tp->c_cc[VINTR] = DEF_INTR; /* default interrupt */ |
526 | tp->c_cc[VQUIT] = DEF_QUIT; /* default quit */ |
527 | tp->c_cc[VEOF] = DEF_EOF; /* default EOF character */ |
528 | tp->c_cc[VEOL] = DEF_EOL; |
529 | tp->c_cc[VSWTC] = DEF_SWITCH; /* default switch character */ |
530 | |
531 | /* Account for special characters seen in input. */ |
532 | if (cp->eol == CR) { |
533 | tp->c_iflag |= ICRNL; /* map CR in input to NL */ |
534 | tp->c_oflag |= ONLCR; /* map NL in output to CR-NL */ |
535 | } |
536 | tp->c_cc[VERASE] = cp->erase; /* set erase character */ |
537 | tp->c_cc[VKILL] = cp->kill; /* set kill character */ |
538 | |
539 | /* Account for the presence or absence of parity bits in input. */ |
540 | switch (cp->parity) { |
541 | case 0: /* space (always 0) parity */ |
542 | // I bet most people go here - they use only 7-bit chars in usernames.... |
543 | break; |
544 | case 1: /* odd parity */ |
545 | tp->c_cflag |= PARODD; |
546 | /* FALLTHROUGH */ |
547 | case 2: /* even parity */ |
548 | tp->c_cflag |= PARENB; |
549 | tp->c_iflag |= INPCK | ISTRIP; |
550 | /* FALLTHROUGH */ |
551 | case (1 | 2): /* no parity bit */ |
552 | tp->c_cflag &= ~CSIZE; |
553 | tp->c_cflag |= CS7; |
554 | // FIXME: wtf? case 3: we saw both even and odd 8-bit bytes - |
555 | // it's probably some umlauts etc, but definitely NOT 7-bit!!! |
556 | // Entire parity detection madness here just begs for deletion... |
557 | break; |
558 | } |
559 | |
560 | /* Account for upper case without lower case. */ |
561 | #ifdef HANDLE_ALLCAPS |
562 | if (cp->capslock) { |
563 | tp->c_iflag |= IUCLC; |
564 | tp->c_lflag |= XCASE; |
565 | tp->c_oflag |= OLCUC; |
566 | } |
567 | #endif |
568 | /* Optionally enable hardware flow control */ |
569 | #ifdef CRTSCTS |
570 | if (op->flags & F_RTSCTS) |
571 | tp->c_cflag |= CRTSCTS; |
572 | #endif |
573 | |
574 | /* Finally, make the new settings effective */ |
575 | /* It's tcsetattr_stdin_TCSANOW() + error check */ |
576 | ioctl_or_perror_and_die(0, TCSETS, tp, "%s: TCSETS", op->tty); |
577 | } |
578 | |
579 | int getty_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
580 | int getty_main(int argc UNUSED_PARAM, char **argv) |
581 | { |
582 | int n; |
583 | pid_t pid; |
584 | char *fakehost = NULL; /* Fake hostname for ut_host */ |
585 | char *logname; /* login name, given to /bin/login */ |
586 | /* Merging these into "struct local" may _seem_ to reduce |
587 | * parameter passing, but today's gcc will inline |
588 | * statics which are called once anyway, so don't do that */ |
589 | struct chardata chardata; /* set by get_logname() */ |
590 | struct termios termios; /* terminal mode bits */ |
591 | struct options options; |
592 | |
593 | chardata = init_chardata; |
594 | |
595 | memset(&options, 0, sizeof(options)); |
596 | options.login = _PATH_LOGIN; /* default login program */ |
597 | options.tty = "tty1"; /* default tty line */ |
598 | options.initstring = ""; /* modem init string */ |
599 | #ifdef ISSUE |
600 | options.issue = ISSUE; /* default issue file */ |
601 | #endif |
602 | |
603 | /* Parse command-line arguments. */ |
604 | parse_args(argv, &options, &fakehost); |
605 | |
606 | logmode = LOGMODE_NONE; |
607 | |
608 | /* Create new session, lose controlling tty, if any */ |
609 | /* docs/ctty.htm says: |
610 | * "This is allowed only when the current process |
611 | * is not a process group leader" - is this a problem? */ |
612 | setsid(); |
613 | /* close stdio, and stray descriptors, just in case */ |
614 | n = xopen(bb_dev_null, O_RDWR); |
615 | /* dup2(n, 0); - no, we need to handle "getty - 9600" too */ |
616 | xdup2(n, 1); |
617 | xdup2(n, 2); |
618 | while (n > 2) |
619 | close(n--); |
620 | |
621 | /* Logging. We want special flavor of error_msg_and_die */ |
622 | die_sleep = 10; |
623 | msg_eol = "\r\n"; |
624 | /* most likely will internally use fd #3 in CLOEXEC mode: */ |
625 | openlog(applet_name, LOG_PID, LOG_AUTH); |
626 | logmode = LOGMODE_BOTH; |
627 | |
628 | #ifdef DEBUGGING |
629 | dbf = xfopen_for_write(DEBUGTERM); |
630 | for (n = 1; argv[n]; n++) { |
631 | debug(argv[n]); |
632 | debug("\n"); |
633 | } |
634 | #endif |
635 | |
636 | /* Open the tty as standard input, if it is not "-" */ |
637 | /* If it's not "-" and not taken yet, it will become our ctty */ |
638 | debug("calling open_tty\n"); |
639 | open_tty(options.tty); |
640 | ndelay_off(0); |
641 | debug("duping\n"); |
642 | xdup2(0, 1); |
643 | xdup2(0, 2); |
644 | |
645 | /* |
646 | * The following ioctl will fail if stdin is not a tty, but also when |
647 | * there is noise on the modem control lines. In the latter case, the |
648 | * common course of action is (1) fix your cables (2) give the modem more |
649 | * time to properly reset after hanging up. SunOS users can achieve (2) |
650 | * by patching the SunOS kernel variable "zsadtrlow" to a larger value; |
651 | * 5 seconds seems to be a good value. |
652 | */ |
653 | /* tcgetattr() + error check */ |
654 | ioctl_or_perror_and_die(0, TCGETS, &termios, "%s: TCGETS", options.tty); |
655 | |
656 | pid = getpid(); |
657 | #ifdef __linux__ |
658 | // FIXME: do we need this? Otherwise "-" case seems to be broken... |
659 | // /* Forcibly make fd 0 our controlling tty, even if another session |
660 | // * has it as a ctty. (Another session loses ctty). */ |
661 | // ioctl(0, TIOCSCTTY, (void*)1); |
662 | /* Make ourself a foreground process group within our session */ |
663 | tcsetpgrp(0, pid); |
664 | #endif |
665 | |
666 | /* Update the utmp file. This tty is ours now! */ |
667 | update_utmp(pid, LOGIN_PROCESS, options.tty, "LOGIN", fakehost); |
668 | |
669 | /* Initialize the termios settings (raw mode, eight-bit, blocking i/o). */ |
670 | debug("calling termios_init\n"); |
671 | termios_init(&termios, options.speeds[0], &options); |
672 | |
673 | /* Write the modem init string and DON'T flush the buffers */ |
674 | if (options.flags & F_INITSTRING) { |
675 | debug("writing init string\n"); |
676 | full_write1_str(options.initstring); |
677 | } |
678 | |
679 | /* Optionally detect the baud rate from the modem status message */ |
680 | debug("before autobaud\n"); |
681 | if (options.flags & F_PARSE) |
682 | auto_baud(line_buf, sizeof(line_buf), &termios); |
683 | |
684 | /* Set the optional timer */ |
685 | alarm(options.timeout); /* if 0, alarm is not set */ |
686 | |
687 | /* Optionally wait for CR or LF before writing /etc/issue */ |
688 | if (options.flags & F_WAITCRLF) { |
689 | char ch; |
690 | |
691 | debug("waiting for cr-lf\n"); |
692 | while (safe_read(STDIN_FILENO, &ch, 1) == 1) { |
693 | debug("read %x\n", (unsigned char)ch); |
694 | ch &= 0x7f; /* strip "parity bit" */ |
695 | if (ch == '\n' || ch == '\r') |
696 | break; |
697 | } |
698 | } |
699 | |
700 | logname = NULL; |
701 | if (!(options.flags & F_NOPROMPT)) { |
702 | /* NB:termios_init already set line speed |
703 | * to options.speeds[0] */ |
704 | int baud_index = 0; |
705 | |
706 | while (1) { |
707 | /* Read the login name. */ |
708 | debug("reading login name\n"); |
709 | logname = get_logname(line_buf, sizeof(line_buf), |
710 | &options, &chardata); |
711 | if (logname) |
712 | break; |
713 | /* we are here only if options.numspeed > 1 */ |
714 | baud_index = (baud_index + 1) % options.numspeed; |
715 | cfsetispeed(&termios, options.speeds[baud_index]); |
716 | cfsetospeed(&termios, options.speeds[baud_index]); |
717 | tcsetattr_stdin_TCSANOW(&termios); |
718 | } |
719 | } |
720 | |
721 | /* Disable timer. */ |
722 | alarm(0); |
723 | |
724 | /* Finalize the termios settings. */ |
725 | termios_final(&options, &termios, &chardata); |
726 | |
727 | /* Now the newline character should be properly written. */ |
728 | full_write(STDOUT_FILENO, "\n", 1); |
729 | |
730 | /* Let the login program take care of password validation. */ |
731 | /* We use PATH because we trust that root doesn't set "bad" PATH, |
732 | * and getty is not suid-root applet. */ |
733 | /* With -n, logname == NULL, and login will ask for username instead */ |
734 | BB_EXECLP(options.login, options.login, "--", logname, NULL); |
735 | bb_error_msg_and_die("%s: can't exec %s", options.tty, options.login); |
736 | } |