/* $OpenBSD: lpc.c,v 1.19 2015/01/16 06:40:18 deraadt Exp $ */ /* $NetBSD: lpc.c,v 1.11 2001/11/14 03:01:15 enami Exp $ */ /* * Copyright (c) 1983, 1993 * The Regents of the University of California. All rights reserved. * * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include #include #include #include #include #include #include #include #include #include #include #include "lp.h" #include "lpc.h" #include "extern.h" #ifndef LPR_OPER #define LPR_OPER "operator" /* group name of lpr operators */ #endif /* * lpc -- line printer control program */ #define MAX_CMDLINE 200 #define MAX_MARGV 20 int fromatty; char cmdline[MAX_CMDLINE]; int margc; char *margv[MAX_MARGV]; static void cmdscanner(void); static struct cmd *getcmd(char *); static void intr(int); static void makeargv(void); static int ingroup(char *); int main(int argc, char **argv) { struct cmd *c; effective_uid = geteuid(); real_uid = getuid(); effective_gid = getegid(); real_gid = getgid(); PRIV_END; /* be safe */ openlog("lpc", 0, LOG_LPR); if (--argc > 0) { c = getcmd(*++argv); if (c == (struct cmd *)-1) { printf("?Ambiguous command\n"); exit(1); } if (c == 0) { printf("?Invalid command\n"); exit(1); } if (c->c_priv && real_uid && ingroup(LPR_OPER) == 0) { printf("?Privileged command\n"); exit(1); } (*c->c_handler)(argc, argv); exit(0); } fromatty = isatty(fileno(stdin)); signal(SIGINT, intr); for (;;) cmdscanner(); } volatile sig_atomic_t gotintr; static void intr(int signo) { if (!fromatty) _exit(0); gotintr = 1; } /* * Command parser. */ static void cmdscanner(void) { struct cmd *c; for (;;) { if (gotintr) { putchar('\n'); gotintr = 0; } if (fromatty) { printf("lpc> "); fflush(stdout); } siginterrupt(SIGINT, 1); if (fgets(cmdline, MAX_CMDLINE, stdin) == NULL) { if (errno == EINTR && gotintr) { siginterrupt(SIGINT, 0); return; } siginterrupt(SIGINT, 0); quit(0, NULL); } siginterrupt(SIGINT, 0); makeargv(); if (margc == 0) break; c = getcmd(margv[0]); if (c == (struct cmd *)-1) { printf("?Ambiguous command\n"); continue; } if (c == 0) { printf("?Invalid command\n"); continue; } if (c->c_priv && getuid() && ingroup(LPR_OPER) == 0) { printf("?Privileged command\n"); continue; } (*c->c_handler)(margc, margv); } } static struct cmd * getcmd(char *name) { char *p, *q; struct cmd *c, *found; int nmatches, longest; longest = 0; nmatches = 0; found = 0; for (c = cmdtab; (p = c->c_name) != NULL; c++) { for (q = name; *q == *p++; q++) if (*q == 0) /* exact match? */ return(c); if (!*q) { /* the name was a prefix */ if (q - name > longest) { longest = q - name; nmatches = 1; found = c; } else if (q - name == longest) nmatches++; } } if (nmatches > 1) return((struct cmd *)-1); return(found); } /* * Slice a string up into argc/argv. */ static void makeargv(void) { char *cp = cmdline; char **ap = margv; margc = 0; while (margc < MAX_MARGV - 1 && (*ap = strsep(&cp, " \t\n")) != NULL) { if (**ap != '\0') { ap++; margc++; } } *ap = NULL; } #define HELPINDENT ((int)sizeof("directory")) /* * Help command. */ void help(int argc, char **argv) { struct cmd *c; if (argc == 1) { int i, j, w; int columns, width = 0, lines; printf("Commands may be abbreviated. Commands are:\n\n"); for (c = cmdtab; c->c_name; c++) { int len = strlen(c->c_name); if (len > width) width = len; } width = (width + 8) &~ 7; columns = 80 / width; if (columns == 0) columns = 1; lines = (NCMDS + columns - 1) / columns; for (i = 0; i < lines; i++) { for (j = 0; j < columns; j++) { c = cmdtab + j * lines + i; if (c->c_name) printf("%s", c->c_name); if (c + lines >= &cmdtab[NCMDS]) { printf("\n"); break; } w = strlen(c->c_name); while (w < width) { w = (w + 8) &~ 7; putchar('\t'); } } } return; } while (--argc > 0) { char *arg; arg = *++argv; c = getcmd(arg); if (c == (struct cmd *)-1) printf("?Ambiguous help command %s\n", arg); else if (c == (struct cmd *)0) printf("?Invalid help command %s\n", arg); else printf("%-*s\t%s\n", HELPINDENT, c->c_name, c->c_help); } } /* * return non-zero if the user is a member of the given group */ static int ingroup(char *grname) { static struct group *gptr = NULL; static gid_t groups[NGROUPS_MAX]; static int ngroups; gid_t gid; int i; if (gptr == NULL) { if ((gptr = getgrnam(grname)) == NULL) { warnx("Warning: unknown group `%s'", grname); return(0); } if ((ngroups = getgroups(NGROUPS_MAX, groups)) < 0) err(1, "getgroups"); } gid = gptr->gr_gid; for (i = 0; i < ngroups; i++) if (gid == groups[i]) return(1); return(0); }