lpc.c revision 1.7
1 /* $NetBSD: lpc.c,v 1.7 1997/10/05 11:52:30 mrg Exp $ */ 2 /* 3 * Copyright (c) 1983, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #ifndef lint 37 static char copyright[] = 38 "@(#) Copyright (c) 1983, 1993\n\ 39 The Regents of the University of California. All rights reserved.\n"; 40 #endif /* not lint */ 41 42 #ifndef lint 43 static char sccsid[] = "@(#)lpc.c 8.3 (Berkeley) 4/28/95"; 44 #endif /* not lint */ 45 46 #include <sys/param.h> 47 48 #include <dirent.h> 49 #include <signal.h> 50 #include <setjmp.h> 51 #include <syslog.h> 52 #include <unistd.h> 53 #include <stdlib.h> 54 #include <stdio.h> 55 #include <ctype.h> 56 #include <string.h> 57 #include <grp.h> 58 #include <sys/param.h> 59 #include "lp.h" 60 #include "lpc.h" 61 #include "extern.h" 62 63 #ifndef LPR_OPER 64 #define LPR_OPER "operator" /* group name of lpr operators */ 65 #endif 66 67 /* 68 * lpc -- line printer control program 69 */ 70 71 #define MAX_CMDLINE 200 72 #define MAX_MARGV 20 73 int fromatty; 74 75 char cmdline[MAX_CMDLINE]; 76 int margc; 77 char *margv[MAX_MARGV]; 78 int top; 79 uid_t uid, euid; 80 81 jmp_buf toplevel; 82 83 static void cmdscanner __P((int)); 84 static struct cmd *getcmd __P((char *)); 85 static void intr __P((int)); 86 static void makeargv __P((void)); 87 static int ingroup __P((char *)); 88 89 int 90 main(argc, argv) 91 int argc; 92 char *argv[]; 93 { 94 register struct cmd *c; 95 96 euid = geteuid(); 97 uid = getuid(); 98 seteuid(uid); 99 name = argv[0]; 100 openlog("lpd", 0, LOG_LPR); 101 102 if (--argc > 0) { 103 c = getcmd(*++argv); 104 if (c == (struct cmd *)-1) { 105 printf("?Ambiguous command\n"); 106 exit(1); 107 } 108 if (c == 0) { 109 printf("?Invalid command\n"); 110 exit(1); 111 } 112 if (c->c_priv && getuid() && ingroup(LPR_OPER) == 0) { 113 printf("?Privileged command\n"); 114 exit(1); 115 } 116 (*c->c_handler)(argc, argv); 117 exit(0); 118 } 119 fromatty = isatty(fileno(stdin)); 120 top = setjmp(toplevel) == 0; 121 if (top) 122 signal(SIGINT, intr); 123 for (;;) { 124 cmdscanner(top); 125 top = 1; 126 } 127 } 128 129 static void 130 intr(signo) 131 int signo; 132 { 133 if (!fromatty) 134 exit(0); 135 longjmp(toplevel, 1); 136 } 137 138 /* 139 * Command parser. 140 */ 141 static void 142 cmdscanner(top) 143 int top; 144 { 145 register struct cmd *c; 146 147 if (!top) 148 putchar('\n'); 149 for (;;) { 150 if (fromatty) { 151 printf("lpc> "); 152 fflush(stdout); 153 } 154 if (fgets(cmdline, MAX_CMDLINE, stdin) == 0) 155 quit(0, NULL); 156 if (cmdline[0] == 0 || cmdline[0] == '\n') 157 break; 158 makeargv(); 159 c = getcmd(margv[0]); 160 if (c == (struct cmd *)-1) { 161 printf("?Ambiguous command\n"); 162 continue; 163 } 164 if (c == 0) { 165 printf("?Invalid command\n"); 166 continue; 167 } 168 if (c->c_priv && getuid() && ingroup(LPR_OPER) == 0) { 169 printf("?Privileged command\n"); 170 continue; 171 } 172 (*c->c_handler)(margc, margv); 173 } 174 longjmp(toplevel, 0); 175 } 176 177 static struct cmd * 178 getcmd(name) 179 register char *name; 180 { 181 register char *p, *q; 182 register struct cmd *c, *found; 183 register int nmatches, longest; 184 185 longest = 0; 186 nmatches = 0; 187 found = 0; 188 for (c = cmdtab; (p = c->c_name) != NULL; c++) { 189 for (q = name; *q == *p++; q++) 190 if (*q == 0) /* exact match? */ 191 return(c); 192 if (!*q) { /* the name was a prefix */ 193 if (q - name > longest) { 194 longest = q - name; 195 nmatches = 1; 196 found = c; 197 } else if (q - name == longest) 198 nmatches++; 199 } 200 } 201 if (nmatches > 1) 202 return((struct cmd *)-1); 203 return(found); 204 } 205 206 /* 207 * Slice a string up into argc/argv. 208 */ 209 static void 210 makeargv() 211 { 212 register char *cp; 213 register char **argp = margv; 214 register int n = 0; 215 216 margc = 0; 217 for (cp = cmdline; *cp && n < MAX_MARGV; n++) { 218 while (isspace(*cp)) 219 cp++; 220 if (*cp == '\0') 221 break; 222 *argp++ = cp; 223 margc += 1; 224 while (*cp != '\0' && !isspace(*cp)) 225 cp++; 226 if (*cp == '\0') 227 break; 228 *cp++ = '\0'; 229 } 230 *argp++ = 0; 231 } 232 233 #define HELPINDENT (sizeof ("directory")) 234 235 /* 236 * Help command. 237 */ 238 void 239 help(argc, argv) 240 int argc; 241 char *argv[]; 242 { 243 register struct cmd *c; 244 245 if (argc == 1) { 246 register int i, j, w; 247 int columns, width = 0, lines; 248 extern int NCMDS; 249 250 printf("Commands may be abbreviated. Commands are:\n\n"); 251 for (c = cmdtab; c->c_name; c++) { 252 int len = strlen(c->c_name); 253 254 if (len > width) 255 width = len; 256 } 257 width = (width + 8) &~ 7; 258 columns = 80 / width; 259 if (columns == 0) 260 columns = 1; 261 lines = (NCMDS + columns - 1) / columns; 262 for (i = 0; i < lines; i++) { 263 for (j = 0; j < columns; j++) { 264 c = cmdtab + j * lines + i; 265 if (c->c_name) 266 printf("%s", c->c_name); 267 if (c + lines >= &cmdtab[NCMDS]) { 268 printf("\n"); 269 break; 270 } 271 w = strlen(c->c_name); 272 while (w < width) { 273 w = (w + 8) &~ 7; 274 putchar('\t'); 275 } 276 } 277 } 278 return; 279 } 280 while (--argc > 0) { 281 register char *arg; 282 arg = *++argv; 283 c = getcmd(arg); 284 if (c == (struct cmd *)-1) 285 printf("?Ambiguous help command %s\n", arg); 286 else if (c == (struct cmd *)0) 287 printf("?Invalid help command %s\n", arg); 288 else 289 printf("%-*s\t%s\n", HELPINDENT, 290 c->c_name, c->c_help); 291 } 292 } 293 294 /* 295 * return non-zero if the user is a member of the given group 296 */ 297 static int 298 ingroup(grname) 299 char *grname; 300 { 301 static struct group *gptr=NULL; 302 static gid_t groups[NGROUPS]; 303 register gid_t gid; 304 register int i; 305 306 if (gptr == NULL) { 307 if ((gptr = getgrnam(grname)) == NULL) { 308 fprintf(stderr, "Warning: unknown group '%s'\n", 309 grname); 310 return(0); 311 } 312 if (getgroups(NGROUPS, groups) < 0) { 313 perror("getgroups"); 314 exit(1); 315 } 316 } 317 gid = gptr->gr_gid; 318 for (i = 0; i < NGROUPS; i++) 319 if (gid == groups[i]) 320 return(1); 321 return(0); 322 } 323
Indexes created Thu Sep 25 08:09:54 GMT 2025