1 /*
2 * Copyright (c) 1983, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 *
6 * %sccs.include.redist.c%
7 */
8
9 #ifndef lint
10 static char copyright[] =
11 "@(#) Copyright (c) 1983, 1993\n\
12 The Regents of the University of California. All rights reserved.\n";
13 #endif /* not lint */
14
15 #ifndef lint
16 static char sccsid[] = "@(#)lpc.c 8.3 (Berkeley) 04/28/95";
17 #endif /* not lint */
18
19 #include <sys/param.h>
20
21 #include <dirent.h>
22 #include <signal.h>
23 #include <setjmp.h>
24 #include <syslog.h>
25 #include <unistd.h>
26 #include <stdlib.h>
27 #include <stdio.h>
28 #include <ctype.h>
29 #include <string.h>
30 #include <grp.h>
31 #include <sys/param.h>
32 #include "lp.h"
33 #include "lpc.h"
34 #include "extern.h"
35
36 #ifndef LPR_OPER
37 #define LPR_OPER "operator" /* group name of lpr operators */
38 #endif
39
40 /*
41 * lpc -- line printer control program
42 */
43
44 int fromatty;
45
46 char cmdline[200];
47 int margc;
48 char *margv[20];
49 int top;
50
51 jmp_buf toplevel;
52
53 static void cmdscanner __P((int));
54 static struct cmd *getcmd __P((char *));
55 static void intr __P((int));
56 static void makeargv __P((void));
57 static int ingroup __P((char *));
58
59 int
main(argc,argv)60 main(argc, argv)
61 int argc;
62 char *argv[];
63 {
64 register struct cmd *c;
65
66 name = argv[0];
67 openlog("lpd", 0, LOG_LPR);
68
69 if (--argc > 0) {
70 c = getcmd(*++argv);
71 if (c == (struct cmd *)-1) {
72 printf("?Ambiguous command\n");
73 exit(1);
74 }
75 if (c == 0) {
76 printf("?Invalid command\n");
77 exit(1);
78 }
79 if (c->c_priv && getuid() && ingroup(LPR_OPER) == 0) {
80 printf("?Privileged command\n");
81 exit(1);
82 }
83 (*c->c_handler)(argc, argv);
84 exit(0);
85 }
86 fromatty = isatty(fileno(stdin));
87 top = setjmp(toplevel) == 0;
88 if (top)
89 signal(SIGINT, intr);
90 for (;;) {
91 cmdscanner(top);
92 top = 1;
93 }
94 }
95
96 static void
intr(signo)97 intr(signo)
98 int signo;
99 {
100 if (!fromatty)
101 exit(0);
102 longjmp(toplevel, 1);
103 }
104
105 /*
106 * Command parser.
107 */
108 static void
cmdscanner(top)109 cmdscanner(top)
110 int top;
111 {
112 register struct cmd *c;
113
114 if (!top)
115 putchar('\n');
116 for (;;) {
117 if (fromatty) {
118 printf("lpc> ");
119 fflush(stdout);
120 }
121 if (fgets(cmdline, sizeof(cmdline), stdin) == 0)
122 quit(0, NULL);
123 if (cmdline[0] == 0 || cmdline[0] == '\n')
124 break;
125 makeargv();
126 c = getcmd(margv[0]);
127 if (c == (struct cmd *)-1) {
128 printf("?Ambiguous command\n");
129 continue;
130 }
131 if (c == 0) {
132 printf("?Invalid command\n");
133 continue;
134 }
135 if (c->c_priv && getuid() && ingroup(LPR_OPER) == 0) {
136 printf("?Privileged command\n");
137 continue;
138 }
139 (*c->c_handler)(margc, margv);
140 }
141 longjmp(toplevel, 0);
142 }
143
144 static struct cmd *
getcmd(name)145 getcmd(name)
146 register char *name;
147 {
148 register char *p, *q;
149 register struct cmd *c, *found;
150 register int nmatches, longest;
151
152 longest = 0;
153 nmatches = 0;
154 found = 0;
155 for (c = cmdtab; p = c->c_name; c++) {
156 for (q = name; *q == *p++; q++)
157 if (*q == 0) /* exact match? */
158 return(c);
159 if (!*q) { /* the name was a prefix */
160 if (q - name > longest) {
161 longest = q - name;
162 nmatches = 1;
163 found = c;
164 } else if (q - name == longest)
165 nmatches++;
166 }
167 }
168 if (nmatches > 1)
169 return((struct cmd *)-1);
170 return(found);
171 }
172
173 /*
174 * Slice a string up into argc/argv.
175 */
176 static void
makeargv()177 makeargv()
178 {
179 register char *cp;
180 register char **argp = margv;
181
182 margc = 0;
183 for (cp = cmdline; *cp;) {
184 while (isspace(*cp))
185 cp++;
186 if (*cp == '\0')
187 break;
188 *argp++ = cp;
189 margc += 1;
190 while (*cp != '\0' && !isspace(*cp))
191 cp++;
192 if (*cp == '\0')
193 break;
194 *cp++ = '\0';
195 }
196 *argp++ = 0;
197 }
198
199 #define HELPINDENT (sizeof ("directory"))
200
201 /*
202 * Help command.
203 */
204 void
help(argc,argv)205 help(argc, argv)
206 int argc;
207 char *argv[];
208 {
209 register struct cmd *c;
210
211 if (argc == 1) {
212 register int i, j, w;
213 int columns, width = 0, lines;
214 extern int NCMDS;
215
216 printf("Commands may be abbreviated. Commands are:\n\n");
217 for (c = cmdtab; c->c_name; c++) {
218 int len = strlen(c->c_name);
219
220 if (len > width)
221 width = len;
222 }
223 width = (width + 8) &~ 7;
224 columns = 80 / width;
225 if (columns == 0)
226 columns = 1;
227 lines = (NCMDS + columns - 1) / columns;
228 for (i = 0; i < lines; i++) {
229 for (j = 0; j < columns; j++) {
230 c = cmdtab + j * lines + i;
231 if (c->c_name)
232 printf("%s", c->c_name);
233 if (c + lines >= &cmdtab[NCMDS]) {
234 printf("\n");
235 break;
236 }
237 w = strlen(c->c_name);
238 while (w < width) {
239 w = (w + 8) &~ 7;
240 putchar('\t');
241 }
242 }
243 }
244 return;
245 }
246 while (--argc > 0) {
247 register char *arg;
248 arg = *++argv;
249 c = getcmd(arg);
250 if (c == (struct cmd *)-1)
251 printf("?Ambiguous help command %s\n", arg);
252 else if (c == (struct cmd *)0)
253 printf("?Invalid help command %s\n", arg);
254 else
255 printf("%-*s\t%s\n", HELPINDENT,
256 c->c_name, c->c_help);
257 }
258 }
259
260 /*
261 * return non-zero if the user is a member of the given group
262 */
263 static int
ingroup(grname)264 ingroup(grname)
265 char *grname;
266 {
267 static struct group *gptr=NULL;
268 static gid_t groups[NGROUPS];
269 register gid_t gid;
270 register int i;
271
272 if (gptr == NULL) {
273 if ((gptr = getgrnam(grname)) == NULL) {
274 fprintf(stderr, "Warning: unknown group '%s'\n",
275 grname);
276 return(0);
277 }
278 if (getgroups(NGROUPS, groups) < 0) {
279 perror("getgroups");
280 exit(1);
281 }
282 }
283 gid = gptr->gr_gid;
284 for (i = 0; i < NGROUPS; i++)
285 if (gid == groups[i])
286 return(1);
287 return(0);
288 }
289