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Diffstat (limited to 'loginutils')
-rw-r--r--loginutils/getty.c172
1 files changed, 84 insertions, 88 deletions
diff --git a/loginutils/getty.c b/loginutils/getty.c
index f033b5a..246bb47 100644
--- a/loginutils/getty.c
+++ b/loginutils/getty.c
@@ -61,7 +61,7 @@ extern void updwtmp(const char *filename, const struct utmp *ut);
#define ISSUE "/etc/issue" /* displayed before the login prompt */
/* Some shorthands for control characters. */
-#define CTL(x) (x ^ 0100) /* Assumes ASCII dialect */
+#define CTL(x) ((x) ^ 0100) /* Assumes ASCII dialect */
#define CR CTL('M') /* carriage return */
#define NL CTL('J') /* line feed */
#define BS CTL('H') /* back space */
@@ -100,6 +100,13 @@ struct chardata {
unsigned char kill; /* kill character */
unsigned char eol; /* end-of-line character */
unsigned char parity; /* what parity did we see */
+ /* (parity & 1): saw odd parity char with 7th bit set */
+ /* (parity & 2): saw even parity char with 7th bit set */
+ /* parity == 0: probably 7-bit, space parity? */
+ /* parity == 1: probably 7-bit, odd parity? */
+ /* parity == 2: probably 7-bit, even parity? */
+ /* parity == 3: definitely 8 bit, no parity! */
+ /* Hmm... with any value of "parity" 8 bit, no parity is possible */
#ifdef HANDLE_ALLCAPS
unsigned char capslock; /* upper case without lower case */
#endif
@@ -135,27 +142,21 @@ static const char opt_string[] ALIGN1 = "I:LH:f:hil:mt:wn";
/* The following is used for understandable diagnostics. */
#ifdef DEBUGGING
-#define debug(s) fprintf(dbf,s); fflush(dbf)
-#define DEBUGTERM "/dev/ttyp0"
static FILE *dbf;
+#define DEBUGTERM "/dev/ttyp0"
+#define debug(...) do { fprintf(dbf, __VA_ARGS__); fflush(dbf); } while (0)
#else
-#define debug(s) /* nothing */
+#define debug(...) ((void)0)
#endif
-/* bcode - convert speed string to speed code; return 0 on failure */
+/* bcode - convert speed string to speed code; return <= 0 on failure */
static int bcode(const char *s)
{
- int r;
- unsigned value = bb_strtou(s, NULL, 10);
- if (errno) {
- return -1;
- }
- r = tty_value_to_baud(value);
- if (r > 0) {
- return r;
- }
- return 0;
+ int value = bb_strtou(s, NULL, 10); /* yes, int is intended! */
+ if (value < 0) /* bad terminating char, overflow, etc */
+ return value;
+ return tty_value_to_baud(value);
}
/* parse_speeds - parse alternate baud rates */
@@ -181,10 +182,10 @@ static void parse_args(char **argv, struct options *op, char **fakehost_p)
{
char *ts;
- opt_complementary = "-2"; /* at least 2 args */
+ opt_complementary = "-2:t+"; /* at least 2 args; -t N */
op->flags = getopt32(argv, opt_string,
&(op->initstring), fakehost_p, &(op->issue),
- &(op->login), &ts);
+ &(op->login), &op->timeout);
argv += optind;
if (op->flags & F_INITSTRING) {
const char *p = op->initstring;
@@ -203,10 +204,7 @@ static void parse_args(char **argv, struct options *op, char **fakehost_p)
}
*q = '\0';
}
- op->flags ^= F_ISSUE; /* invert flag show /etc/issue */
- if (op->flags & F_TIMEOUT) {
- op->timeout = xatoi_u(ts);
- }
+ op->flags ^= F_ISSUE; /* invert flag "show /etc/issue" */
debug("after getopt\n");
/* we loosen up a bit and accept both "baudrate tty" and "tty baudrate" */
@@ -219,8 +217,11 @@ static void parse_args(char **argv, struct options *op, char **fakehost_p)
}
parse_speeds(op, ts);
+// TODO: if applet_name is set to "getty: TTY", bb_error_msg's get simpler!
+// grep for "%s:"
+
if (argv[2])
- setenv("TERM", argv[2], 1);
+ xsetenv("TERM", argv[2]);
debug("exiting parse_args\n");
}
@@ -230,37 +231,37 @@ static void open_tty(const char *tty)
{
/* Set up new standard input, unless we are given an already opened port. */
if (NOT_LONE_DASH(tty)) {
- struct stat st;
- int cur_dir_fd;
- int fd;
+// struct stat st;
+// int cur_dir_fd;
+// int fd;
/* Sanity checks... */
- cur_dir_fd = xopen(".", O_DIRECTORY | O_NONBLOCK);
- xchdir("/dev");
- xstat(tty, &st);
- if ((st.st_mode & S_IFMT) != S_IFCHR)
- bb_error_msg_and_die("%s: not a character device", tty);
+// cur_dir_fd = xopen(".", O_DIRECTORY | O_NONBLOCK);
+// xchdir("/dev");
+// xstat(tty, &st);
+// if ((st.st_mode & S_IFMT) != S_IFCHR)
+// bb_error_msg_and_die("%s: not a character device", tty);
+
+ if (tty[0] != '/')
+ tty = xasprintf("/dev/%s", tty); /* will leak it */
/* Open the tty as standard input. */
debug("open(2)\n");
- fd = xopen(tty, O_RDWR | O_NONBLOCK);
+ close(0);
+ /*fd =*/ xopen(tty, O_RDWR | O_NONBLOCK); /* uses fd 0 */
- /* Restore current directory */
- fchdir(cur_dir_fd);
+// /* Restore current directory */
+// fchdir(cur_dir_fd);
/* Open the tty as standard input, continued */
- xdup2(fd, 0);
- /* fd is >= cur_dir_fd, and cur_dir_fd gets closed too here: */
- while (fd > 2)
- close(fd--);
-
- /* Set proper protections and ownership. Mode 0622
- * is suitable for SYSV < 4 because /bin/login does not change
- * protections. SunOS 4 login will change the protections to 0620
- * (write access for group tty) after the login has succeeded.
- */
+// xmove_fd(fd, 0);
+// /* fd is >= cur_dir_fd, and cur_dir_fd gets closed too here: */
+// while (fd > 2)
+// close(fd--);
+
+ /* Set proper protections and ownership. */
fchown(0, 0, 0); /* 0:0 */
- fchmod(0, 0622); /* crw--w--w- */
+ fchmod(0, 0620); /* crw--w---- */
} else {
/*
* Standard input should already be connected to an open port. Make
@@ -286,9 +287,8 @@ static void termios_init(struct termios *tp, int speed, struct options *op)
#endif
tp->c_cflag = CS8 | HUPCL | CREAD | speed;
- if (op->flags & F_LOCAL) {
+ if (op->flags & F_LOCAL)
tp->c_cflag |= CLOCAL;
- }
tp->c_iflag = tp->c_lflag = tp->c_line = 0;
tp->c_oflag = OPOST | ONLCR;
@@ -397,11 +397,11 @@ static char *get_logname(char *logname, unsigned size_logname,
char ascval; /* low 7 bits of input character */
int bits; /* # of "1" bits per character */
int mask; /* mask with 1 bit up */
- static const char erase[][3] = { /* backspace-space-backspace */
+ static const char erase[][3] = {/* backspace-space-backspace */
"\010\040\010", /* space parity */
"\010\040\010", /* odd parity */
"\210\240\210", /* even parity */
- "\210\240\210", /* no parity */
+ "\010\040\010", /* 8 bit no parity */
};
/* NB: *cp is pre-initialized with init_chardata */
@@ -434,12 +434,11 @@ static char *get_logname(char *logname, unsigned size_logname,
return NULL;
/* Do parity bit handling. */
- ascval = c & 0177;
- if (!(op->flags & F_LOCAL) && (c != ascval)) { /* "parity" bit on ? */
+ if (!(op->flags & F_LOCAL) && (c & 0x80)) { /* "parity" bit on? */
bits = 1;
mask = 1;
- while (mask & 0177) {
- if (mask & ascval)
+ while (mask & 0x7f) {
+ if (mask & c)
bits++; /* count "1" bits */
mask <<= 1;
}
@@ -448,6 +447,7 @@ static char *get_logname(char *logname, unsigned size_logname,
}
/* Do erase, kill and end-of-line processing. */
+ ascval = c & 0x7f;
switch (ascval) {
case CR:
case NL:
@@ -507,7 +507,6 @@ static char *get_logname(char *logname, unsigned size_logname,
static void termios_final(struct options *op, struct termios *tp, struct chardata *cp)
{
/* General terminal-independent stuff. */
-
tp->c_iflag |= IXON | IXOFF; /* 2-way flow control */
tp->c_lflag |= ICANON | ISIG | ECHO | ECHOE | ECHOK | ECHOKE;
/* no longer| ECHOCTL | ECHOPRT */
@@ -520,7 +519,6 @@ static void termios_final(struct options *op, struct termios *tp, struct chardat
tp->c_cc[VSWTC] = DEF_SWITCH; /* default switch character */
/* Account for special characters seen in input. */
-
if (cp->eol == CR) {
tp->c_iflag |= ICRNL; /* map CR in input to NL */
tp->c_oflag |= ONLCR; /* map NL in output to CR-NL */
@@ -529,9 +527,9 @@ static void termios_final(struct options *op, struct termios *tp, struct chardat
tp->c_cc[VKILL] = cp->kill; /* set kill character */
/* Account for the presence or absence of parity bits in input. */
-
switch (cp->parity) {
case 0: /* space (always 0) parity */
+// I bet most people go here - they use only 7-bit chars in usernames....
break;
case 1: /* odd parity */
tp->c_cflag |= PARODD;
@@ -543,6 +541,9 @@ static void termios_final(struct options *op, struct termios *tp, struct chardat
case (1 | 2): /* no parity bit */
tp->c_cflag &= ~CSIZE;
tp->c_cflag |= CS7;
+// FIXME: wtf? case 3: we saw both even and odd 8-bit bytes -
+// it's probably some umlauts etc, but definitely NOT 7-bit!!!
+// Entire parity detection madness here just begs for deletion...
break;
}
@@ -555,14 +556,12 @@ static void termios_final(struct options *op, struct termios *tp, struct chardat
}
#endif
/* Optionally enable hardware flow control */
-
#ifdef CRTSCTS
if (op->flags & F_RTSCTS)
tp->c_cflag |= CRTSCTS;
#endif
/* Finally, make the new settings effective */
-
ioctl_or_perror_and_die(0, TCSETS, tp, "%s: TCSETS", op->tty);
}
@@ -634,6 +633,8 @@ int getty_main(int argc, char **argv)
struct termios termios; /* terminal mode bits */
struct options options;
+ chardata = init_chardata;
+
memset(&options, 0, sizeof(options));
options.login = _PATH_LOGIN; /* default login program */
options.tty = "tty1"; /* default tty line */
@@ -642,9 +643,9 @@ int getty_main(int argc, char **argv)
options.issue = ISSUE; /* default issue file */
#endif
- /* Already too late because of theoretical
- * possibility of getty --help somehow triggered
- * inadvertently before we reach this. Oh well. */
+ /* Parse command-line arguments. */
+ parse_args(argv, &options, &fakehost);
+
logmode = LOGMODE_NONE;
/* Create new session, lose controlling tty, if any */
@@ -652,16 +653,18 @@ int getty_main(int argc, char **argv)
* "This is allowed only when the current process
* is not a process group leader" - is this a problem? */
setsid();
-
+ /* close stdio, and stray descriptors, just in case */
n = xopen(bb_dev_null, O_RDWR);
- /* dup2(n, 0); - no, because of possible "getty - 9600" */
- dup2(n, 1);
- dup2(n, 2);
+ /* dup2(n, 0); - no, we need to handle "getty - 9600" too */
+ xdup2(n, 1);
+ xdup2(n, 2);
while (n > 2)
close(n--);
- /* We want special flavor of error_msg_and_die */
+
+ /* Logging. We want special flavor of error_msg_and_die */
die_sleep = 10;
msg_eol = "\r\n";
+ /* most likely will internally use fd #3 in CLOEXEC mode: */
openlog(applet_name, LOG_PID, LOG_AUTH);
logmode = LOGMODE_BOTH;
@@ -673,15 +676,12 @@ int getty_main(int argc, char **argv)
}
#endif
- /* Parse command-line arguments. */
- parse_args(argv, &options, &fakehost);
-
- debug("calling open_tty\n");
/* Open the tty as standard input, if it is not "-" */
+ /* If it's not "-" and not taken yet, it will become our ctty */
+ debug("calling open_tty\n");
open_tty(options.tty);
-
- debug("duping\n");
ndelay_off(0);
+ debug("duping\n");
xdup2(0, 1);
xdup2(0, 2);
@@ -695,17 +695,18 @@ int getty_main(int argc, char **argv)
*/
ioctl_or_perror_and_die(0, TCGETS, &termios, "%s: TCGETS", options.tty);
-#if ENABLE_FEATURE_UTMP
- /* Update the utmp file */
- update_utmp(options.tty, fakehost);
-#endif
-
#ifdef __linux__
- /* Make ourself a foreground process group within our session */
- tcsetpgrp(0, getpid());
+// FIXME: do we need this? Otherwise "-" case seems to be broken...
// /* Forcibly make fd 0 our controlling tty, even if another session
// * has it as a ctty. (Another session loses ctty). */
// ioctl(0, TIOCSCTTY, (void*)1);
+ /* Make ourself a foreground process group within our session */
+ tcsetpgrp(0, getpid());
+#endif
+
+#if ENABLE_FEATURE_UTMP
+ /* Update the utmp file. This tty is ours now! */
+ update_utmp(options.tty, fakehost);
#endif
/* Initialize the termios settings (raw mode, eight-bit, blocking i/o). */
@@ -724,8 +725,7 @@ int getty_main(int argc, char **argv)
auto_baud(line_buf, sizeof(line_buf), &termios);
/* Set the optional timer */
- if (options.timeout)
- alarm(options.timeout);
+ alarm(options.timeout); /* if 0, alarm is not set */
/* Optionally wait for CR or LF before writing /etc/issue */
if (options.flags & F_WAITCRLF) {
@@ -733,17 +733,14 @@ int getty_main(int argc, char **argv)
debug("waiting for cr-lf\n");
while (safe_read(0, &ch, 1) == 1) {
+ debug("read %x\n", (unsigned char)ch);
ch &= 0x7f; /* strip "parity bit" */
-#ifdef DEBUGGING
- fprintf(dbf, "read %c\n", ch);
-#endif
if (ch == '\n' || ch == '\r')
break;
}
}
logname = NULL;
- chardata = init_chardata;
if (!(options.flags & F_NOPROMPT)) {
/* NB:termios_init already set line speed
* to options.speeds[0] */
@@ -753,7 +750,7 @@ int getty_main(int argc, char **argv)
/* Read the login name. */
debug("reading login name\n");
logname = get_logname(line_buf, sizeof(line_buf),
- &options, &chardata, &termios);
+ &options, &chardata, &termios);
if (logname)
break;
/* we are here only if options.numspeed > 1 */
@@ -765,8 +762,7 @@ int getty_main(int argc, char **argv)
}
/* Disable timer. */
- if (options.timeout)
- alarm(0);
+ alarm(0);
/* Finalize the termios settings. */
termios_final(&options, &termios, &chardata);
@@ -777,7 +773,7 @@ int getty_main(int argc, char **argv)
/* Let the login program take care of password validation. */
/* We use PATH because we trust that root doesn't set "bad" PATH,
* and getty is not suid-root applet. */
- /* Hmm... with -n, logname == NULL! Is it ok? */
+ /* With -n, logname == NULL, and login will ask for username instead */
BB_EXECLP(options.login, options.login, "--", logname, NULL);
bb_error_msg_and_die("%s: can't exec %s", options.tty, options.login);
}
generated by cgit v1.1 at 2024-11-17 15:42:10 +0000