1 /*-
2 * Copyright (c) 2014 The FreeBSD Foundation
3 * All rights reserved.
4 *
5 * This software was developed by Edward Tomasz Napierala under sponsorship
6 * from the FreeBSD Foundation.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 */
30
31 /*
32 * All the "defined" stuff is for handling variables,
33 * such as ${OSNAME}, in maps.
34 */
35
36 #include <sys/cdefs.h>
37 __FBSDID("$FreeBSD$");
38
39 #include <sys/types.h>
40 #include <sys/time.h>
41 #include <sys/ioctl.h>
42 #include <sys/param.h>
43 #include <sys/linker.h>
44 #include <sys/mount.h>
45 #include <sys/socket.h>
46 #include <sys/stat.h>
47 #include <sys/wait.h>
48 #include <sys/utsname.h>
49 #include <assert.h>
50 #include <ctype.h>
51 #include <errno.h>
52 #include <fcntl.h>
53 #include <libgen.h>
54 #include <netdb.h>
55 #include <signal.h>
56 #include <stdbool.h>
57 #include <stdint.h>
58 #include <stdio.h>
59 #include <stdlib.h>
60 #include <string.h>
61 #include <unistd.h>
62
63 #include <libutil.h>
64
65 #include "common.h"
66
67 static TAILQ_HEAD(, defined_value) defined_values;
68
69 static const char *
defined_find(const char * name)70 defined_find(const char *name)
71 {
72 struct defined_value *d;
73
74 TAILQ_FOREACH(d, &defined_values, d_next) {
75 if (strcmp(d->d_name, name) == 0)
76 return (d->d_value);
77 }
78
79 return (NULL);
80 }
81
82 char *
defined_expand(const char * string)83 defined_expand(const char *string)
84 {
85 const char *value;
86 char c, *expanded, *name;
87 int i, ret, before_len = 0, name_off = 0, name_len = 0, after_off = 0;
88 bool backslashed = false, bracketed = false;
89
90 expanded = checked_strdup(string);
91
92 for (i = 0; string[i] != '\0'; i++) {
93 c = string[i];
94 if (c == '\\' && backslashed == false) {
95 backslashed = true;
96 continue;
97 }
98 if (backslashed) {
99 backslashed = false;
100 continue;
101 }
102 backslashed = false;
103 if (c != '$')
104 continue;
105
106 /*
107 * The 'before_len' variable contains the number
108 * of characters before the '$'.
109 */
110 before_len = i;
111 assert(i + 1 < (int)strlen(string));
112 if (string[i + 1] == '{')
113 bracketed = true;
114
115 if (string[i + 1] == '\0') {
116 log_warnx("truncated variable");
117 return (NULL);
118 }
119
120 /*
121 * Skip '$'.
122 */
123 i++;
124
125 if (bracketed) {
126 if (string[i + 1] == '\0') {
127 log_warnx("truncated variable");
128 return (NULL);
129 }
130
131 /*
132 * Skip '{'.
133 */
134 i++;
135 }
136
137 /*
138 * The 'name_off' variable contains the number
139 * of characters before the variable name,
140 * including the "$" or "${".
141 */
142 name_off = i;
143
144 for (; string[i] != '\0'; i++) {
145 c = string[i];
146 /*
147 * XXX: Decide on the set of characters that can be
148 * used in a variable name.
149 */
150 if (isalnum(c) || c == '_')
151 continue;
152
153 /*
154 * End of variable name.
155 */
156 if (bracketed) {
157 if (c != '}')
158 continue;
159
160 /*
161 * The 'after_off' variable contains the number
162 * of characters before the rest of the string,
163 * i.e. after the variable name.
164 */
165 after_off = i + 1;
166 assert(i > 1);
167 assert(i - 1 > name_off);
168 name_len = i - name_off;
169 break;
170 }
171
172 after_off = i;
173 assert(i > 1);
174 assert(i > name_off);
175 name_len = i - name_off;
176 break;
177 }
178
179 name = strndup(string + name_off, name_len);
180 if (name == NULL)
181 log_err(1, "strndup");
182 value = defined_find(name);
183 if (value == NULL) {
184 log_warnx("undefined variable ${%s}", name);
185 return (NULL);
186 }
187
188 /*
189 * Concatenate it back.
190 */
191 ret = asprintf(&expanded, "%.*s%s%s",
192 before_len, string, value, string + after_off);
193 if (ret < 0)
194 log_err(1, "asprintf");
195
196 //log_debugx("\"%s\" expanded to \"%s\"", string, expanded);
197 free(name);
198
199 /*
200 * Figure out where to start searching for next variable.
201 */
202 string = expanded;
203 i = before_len + strlen(value);
204 backslashed = bracketed = false;
205 before_len = name_off = name_len = after_off = 0;
206 assert(i <= (int)strlen(string));
207 }
208
209 if (before_len != 0 || name_off != 0 || name_len != 0 || after_off != 0) {
210 log_warnx("truncated variable");
211 return (NULL);
212 }
213
214 return (expanded);
215 }
216
217 static void
defined_add(const char * name,const char * value)218 defined_add(const char *name, const char *value)
219 {
220 struct defined_value *d;
221 const char *found;
222
223 found = defined_find(name);
224 if (found != NULL)
225 log_errx(1, "variable %s already defined", name);
226
227 log_debugx("defining variable %s=%s", name, value);
228
229 d = calloc(sizeof(*d), 1);
230 if (d == NULL)
231 log_err(1, "calloc");
232 d->d_name = checked_strdup(name);
233 d->d_value = checked_strdup(value);
234
235 TAILQ_INSERT_TAIL(&defined_values, d, d_next);
236 }
237
238 void
defined_parse_and_add(char * def)239 defined_parse_and_add(char *def)
240 {
241 char *name, *value;
242
243 value = def;
244 name = strsep(&value, "=");
245
246 if (value == NULL || value[0] == '\0')
247 log_errx(1, "missing variable value");
248 if (name == NULL || name[0] == '\0')
249 log_errx(1, "missing variable name");
250
251 defined_add(name, value);
252 }
253
254 void
defined_init(void)255 defined_init(void)
256 {
257 struct utsname name;
258 int error;
259
260 TAILQ_INIT(&defined_values);
261
262 error = uname(&name);
263 if (error != 0)
264 log_err(1, "uname");
265
266 defined_add("ARCH", name.machine);
267 defined_add("CPU", name.machine);
268 defined_add("HOST", name.nodename);
269 defined_add("OSNAME", name.sysname);
270 defined_add("OSREL", name.release);
271 defined_add("OSVERS", name.version);
272 }
273