1 /*-
2 * Copyright (c) 2015-2021 Baptiste Daroussin <[email protected]>
3 * Copyright (c) 2015 Xin LI <[email protected]>
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer
10 * in this position and unchanged.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27 #include <sys/cdefs.h>
28 #include <sys/capsicum.h>
29 #include <sys/types.h>
30 #include <sys/sbuf.h>
31
32 #include <capsicum_helpers.h>
33 #include <ctype.h>
34 #include <err.h>
35 #include <errno.h>
36 #include <stdbool.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <string.h>
40 #include <unistd.h>
41 #include <xlocale.h>
42
43 typedef enum {
44 /* state condition to transit to next state */
45 INIT, /* '$' */
46 DELIM_SEEN, /* letter */
47 KEYWORD, /* punctuation mark */
48 PUNC_SEEN, /* ':' -> _SVN; space -> TEXT */
49 PUNC_SEEN_SVN, /* space */
50 TEXT
51 } analyzer_states;
52
53 static int
scan(FILE * fp,const char * name,bool quiet)54 scan(FILE *fp, const char *name, bool quiet)
55 {
56 int c;
57 bool hasid = false;
58 bool subversion = false;
59 analyzer_states state = INIT;
60 FILE* buffp;
61 char *buf;
62 size_t sz;
63 locale_t l;
64
65 l = newlocale(LC_ALL_MASK, "C", NULL);
66 sz = 0;
67 buf = NULL;
68 buffp = open_memstream(&buf, &sz);
69 if (buffp == NULL)
70 err(EXIT_FAILURE, "open_memstream()");
71
72 if (name != NULL)
73 printf("%s:\n", name);
74
75 while ((c = fgetc(fp)) != EOF) {
76 switch (state) {
77 case INIT:
78 if (c == '$') {
79 /* Transit to DELIM_SEEN if we see $ */
80 state = DELIM_SEEN;
81 } else {
82 /* Otherwise, stay in INIT state */
83 continue;
84 }
85 break;
86 case DELIM_SEEN:
87 if (isalpha_l(c, l)) {
88 /* Transit to KEYWORD if we see letter */
89 if (buf != NULL)
90 memset(buf, 0, sz);
91 rewind(buffp);
92 fputc('$', buffp);
93 fputc(c, buffp);
94 state = KEYWORD;
95
96 continue;
97 } else if (c == '$') {
98 /* Or, stay in DELIM_SEEN if more $ */
99 continue;
100 } else {
101 /* Otherwise, transit back to INIT */
102 state = INIT;
103 }
104 break;
105 case KEYWORD:
106 fputc(c, buffp);
107
108 if (isalpha_l(c, l)) {
109 /*
110 * Stay in KEYWORD if additional letter is seen
111 */
112 continue;
113 } else if (c == ':') {
114 /*
115 * See ':' for the first time, transit to
116 * PUNC_SEEN.
117 */
118 state = PUNC_SEEN;
119 subversion = false;
120 } else if (c == '$') {
121 /*
122 * Incomplete ident. Go back to DELIM_SEEN
123 * state because we see a '$' which could be
124 * the beginning of a keyword.
125 */
126 state = DELIM_SEEN;
127 } else {
128 /*
129 * Go back to INIT state otherwise.
130 */
131 state = INIT;
132 }
133 break;
134 case PUNC_SEEN:
135 case PUNC_SEEN_SVN:
136 fputc(c, buffp);
137
138 switch (c) {
139 case ':':
140 /*
141 * If we see '::' (seen : in PUNC_SEEN),
142 * activate subversion treatment and transit
143 * to PUNC_SEEN_SVN state.
144 *
145 * If more than two :'s were seen, the ident
146 * is invalid and we would therefore go back
147 * to INIT state.
148 */
149 if (state == PUNC_SEEN) {
150 state = PUNC_SEEN_SVN;
151 subversion = true;
152 } else {
153 state = INIT;
154 }
155 break;
156 case ' ':
157 /*
158 * A space after ':' or '::' indicates we are at the
159 * last component of potential ident.
160 */
161 state = TEXT;
162 break;
163 default:
164 /* All other characters are invalid */
165 state = INIT;
166 break;
167 }
168 break;
169 case TEXT:
170 fputc(c, buffp);
171
172 if (iscntrl_l(c, l)) {
173 /* Control characters are not allowed in this state */
174 state = INIT;
175 } else if (c == '$') {
176 fflush(buffp);
177 /*
178 * valid ident should end with a space.
179 *
180 * subversion extension uses '#' to indicate that
181 * the keyword expansion have exceeded the fixed
182 * width, so it is also permitted if we are in
183 * subversion mode. No length check is enforced
184 * because GNU RCS ident(1) does not do it either.
185 */
186 c = buf[strlen(buf) -2 ];
187 if (c == ' ' || (subversion && c == '#')) {
188 printf(" %s\n", buf);
189 hasid = true;
190 }
191 state = INIT;
192 }
193 /* Other characters: stay in the state */
194 break;
195 }
196 }
197 fclose(buffp);
198 free(buf);
199 freelocale(l);
200
201 if (!hasid) {
202 if (!quiet)
203 fprintf(stderr, "%s warning: no id keywords in %s\n",
204 getprogname(), name ? name : "standard input");
205
206 return (EXIT_FAILURE);
207 }
208
209 return (EXIT_SUCCESS);
210 }
211
212 int
main(int argc,char ** argv)213 main(int argc, char **argv)
214 {
215 bool quiet = false;
216 int ch, i, *fds, fd;
217 int ret = EXIT_SUCCESS;
218 size_t nfds;
219 FILE *fp;
220
221 while ((ch = getopt(argc, argv, "qV")) != -1) {
222 switch (ch) {
223 case 'q':
224 quiet = true;
225 break;
226 case 'V':
227 /* Do nothing, compat with GNU rcs's ident */
228 return (EXIT_SUCCESS);
229 default:
230 errx(EXIT_FAILURE, "usage: %s [-q] [-V] [file...]",
231 getprogname());
232 }
233 }
234
235 argc -= optind;
236 argv += optind;
237
238 if (caph_limit_stdio() < 0)
239 err(EXIT_FAILURE, "unable to limit stdio");
240
241 if (argc == 0) {
242 nfds = 1;
243 fds = malloc(sizeof(*fds));
244 if (fds == NULL)
245 err(EXIT_FAILURE, "unable to allocate fds array");
246 fds[0] = STDIN_FILENO;
247 } else {
248 nfds = argc;
249 fds = malloc(sizeof(*fds) * nfds);
250 if (fds == NULL)
251 err(EXIT_FAILURE, "unable to allocate fds array");
252
253 for (i = 0; i < argc; i++) {
254 fds[i] = fd = open(argv[i], O_RDONLY);
255 if (fd < 0) {
256 warn("%s", argv[i]);
257 ret = EXIT_FAILURE;
258 continue;
259 }
260 if (caph_limit_stream(fd, CAPH_READ) < 0)
261 err(EXIT_FAILURE,
262 "unable to limit fcntls/rights for %s",
263 argv[i]);
264 }
265 }
266
267 /* Enter Capsicum sandbox. */
268 if (caph_enter() < 0)
269 err(EXIT_FAILURE, "unable to enter capability mode");
270
271 for (i = 0; i < (int)nfds; i++) {
272 if (fds[i] < 0)
273 continue;
274
275 fp = fdopen(fds[i], "r");
276 if (fp == NULL) {
277 warn("%s", argv[i]);
278 ret = EXIT_FAILURE;
279 continue;
280 }
281 if (scan(fp, argc == 0 ? NULL : argv[i], quiet) != EXIT_SUCCESS)
282 ret = EXIT_FAILURE;
283 fclose(fp);
284 }
285
286 return (ret);
287 }
288