/* * rcvtty.c -- a rcvmail program (a lot like rcvalert) handling IPC ttys * * $Id: rcvtty.c,v 1.1.1.1 1999-02-07 18:14:16 danw Exp $ */ #include #include #include #include #include #include #include #include #ifndef UTMP_FILE # ifdef _PATH_UTMP # define UTMP_FILE _PATH_UTMP # else # define UTMP_FILE "/etc/utmp" # endif #endif #define SCANFMT \ "%2(hour{dtimenow}):%02(min{dtimenow}): %<(size)%5(size) %>%<{encrypted}E%>\ %<(mymbox{from})%<{to}To:%14(friendly{to})%>%>%<(zero)%17(friendly{from})%> \ %{subject}%<{body}<<%{body}>>%>" static struct swit switches[] = { #define BIFFSW 0 { "biff", 0 }, #define FORMSW 1 { "form formatfile", 0 }, #define FMTSW 2 { "format string", 5 }, #define WIDTHSW 3 { "width columns", 0 }, #define NLSW 4 { "newline", 0 }, #define NNLSW 5 { "nonewline", 0 }, #define BELSW 6 { "bell", 0 }, #define NBELSW 7 { "nobell", 0 }, #define VERSIONSW 8 { "version", 0 }, #define HELPSW 9 { "help", 4 }, { NULL, 0 } }; static jmp_buf myctx; static int bell = 1; static int newline = 1; static int biff = 0; static int width = 0; static char *form = NULL; static char *format = NULL; /* * external prototypes */ char *getusername(void); /* * static prototypes */ static RETSIGTYPE alrmser (int); static int message_fd (char **); static int header_fd (void); static void alert (char *, int); int main (int argc, char **argv) { int md, vecp = 0; char *cp, *user, buf[BUFSIZ], tty[BUFSIZ]; char **argp, **arguments, *vec[MAXARGS]; struct utmp ut; register FILE *uf; #ifdef LOCALE setlocale(LC_ALL, ""); #endif invo_name = r1bindex (argv[0], '/'); /* read user profile/context */ context_read(); mts_init (invo_name); arguments = getarguments (invo_name, argc, argv, 1); argp = arguments; while ((cp = *argp++)) { if (*cp == '-') { switch (smatch (++cp, switches)) { case AMBIGSW: ambigsw (cp, switches); done (1); case UNKWNSW: vec[vecp++] = --cp; continue; case HELPSW: snprintf (buf, sizeof(buf), "%s [command ...]", invo_name); print_help (buf, switches, 1); done (1); case VERSIONSW: print_version(invo_name); done (1); case BIFFSW: biff = 1; continue; case FORMSW: if (!(form = *argp++) || *form == '-') adios (NULL, "missing argument to %s", argp[-2]); format = NULL; continue; case FMTSW: if (!(format = *argp++) || *format == '-') adios (NULL, "missing argument to %s", argp[-2]); form = NULL; continue; case WIDTHSW: if (!(cp = *argp++) || *cp == '-') adios(NULL, "missing argument to %s", argp[-2]); width = atoi(cp); continue; case NLSW: newline = 1; continue; case NNLSW: newline = 0; continue; case BELSW: bell = 1; continue; case NBELSW: bell = 0; continue; } } vec[vecp++] = cp; } vec[vecp] = 0; if ((md = vecp ? message_fd (vec) : header_fd ()) == NOTOK) exit (RCV_MBX); user = getusername(); if ((uf = fopen (UTMP_FILE, "r")) == NULL) exit (RCV_MBX); while (fread ((char *) &ut, sizeof(ut), 1, uf) == 1) if (ut.ut_name[0] != 0 && strncmp (user, ut.ut_name, sizeof(ut.ut_name)) == 0) { strncpy (tty, ut.ut_line, sizeof(ut.ut_line)); alert (tty, md); } fclose (uf); exit (RCV_MOK); } static RETSIGTYPE alrmser (int i) { #ifndef RELIABLE_SIGNALS SIGNAL (SIGALRM, alrmser); #endif longjmp (myctx, 1); } static int message_fd (char **vec) { pid_t child_id; int bytes, fd, seconds; char tmpfil[BUFSIZ]; struct stat st; unlink (mktemp (strncpy (tmpfil, "/tmp/rcvttyXXXXX", sizeof(tmpfil)))); if ((fd = open (tmpfil, O_RDWR | O_CREAT | O_TRUNC, 0600)) == NOTOK) return header_fd (); unlink (tmpfil); if ((child_id = vfork()) == NOTOK) { /* fork error */ close (fd); return header_fd (); } else if (child_id) { /* parent process */ if (!setjmp (myctx)) { SIGNAL (SIGALRM, alrmser); bytes = fstat(fileno (stdin), &st) != NOTOK ? (int) st.st_size : 100; /* amount of time to wait depends on message size */ if (bytes <= 100) { /* give at least 5 minutes */ seconds = 300; } else if (bytes >= 90000) { /* but 30 minutes should be long enough */ seconds = 1800; } else { seconds = (bytes / 60) + 300; } alarm ((unsigned int) seconds); pidwait(child_id, OK); alarm (0); if (fstat (fd, &st) != NOTOK && st.st_size > (off_t) 0) return fd; } else { /* * Ruthlessly kill the child and anything * else in its process group. */ KILLPG(child_id, SIGKILL); } close (fd); return header_fd (); } /* child process */ rewind (stdin); if (dup2 (fd, 1) == NOTOK || dup2 (fd, 2) == NOTOK) _exit (-1); closefds (3); setpgid ((pid_t) 0, getpid ()); /* put in own process group */ execvp (vec[0], vec); _exit (-1); } static int header_fd (void) { int fd; char *nfs, tmpfil[BUFSIZ]; strncpy (tmpfil, m_tmpfil (invo_name), sizeof(tmpfil)); if ((fd = open (tmpfil, O_RDWR | O_CREAT | O_TRUNC, 0600)) == NOTOK) return NOTOK; unlink (tmpfil); rewind (stdin); /* get new format string */ nfs = new_fs (form, format, SCANFMT); scan (stdin, 0, 0, nfs, width, 0, 0, NULL, 0L, 0); if (newline) write (fd, "\n\r", 2); write (fd, scanl, strlen (scanl)); if (bell) write (fd, "\007", 1); return fd; } static void alert (char *tty, int md) { int i, td, mask; char buffer[BUFSIZ], ttyspec[BUFSIZ]; struct stat st; snprintf (ttyspec, sizeof(ttyspec), "/dev/%s", tty); /* * The mask depends on whether we are checking for * write permission based on `biff' or `mesg'. */ mask = biff ? S_IEXEC : (S_IWRITE >> 3); if (stat (ttyspec, &st) == NOTOK || (st.st_mode & mask) == 0) return; if (!setjmp (myctx)) { SIGNAL (SIGALRM, alrmser); alarm (2); td = open (ttyspec, O_WRONLY); alarm (0); if (td == NOTOK) return; } else { alarm (0); return; } lseek (md, (off_t) 0, SEEK_SET); while ((i = read (md, buffer, sizeof(buffer))) > 0) if (write (td, buffer, i) != i) break; close (td); }