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$"); 38 39 #include <sys/types.h> 40 #include <sys/time.h> 41 #include <sys/ioctl.h> 42 #include <sys/param.h> 43 #include <sys/linker.h> 44 #include <sys/mount.h> 45 #include <sys/socket.h> 46 #include <sys/stat.h> 47 #include <sys/wait.h> 48 #include <sys/utsname.h> 49 #include <assert.h> 50 #include <ctype.h> 51 #include <errno.h> 52 #include <fcntl.h> 53 #include <libgen.h> 54 #include <libutil.h> 55 #include <netdb.h> 56 #include <signal.h> 57 #include <stdbool.h> 58 #include <stdint.h> 59 #include <stdio.h> 60 #include <stdlib.h> 61 #include <string.h> 62 #include <unistd.h> 63 64 #include "common.h" 65 66 static TAILQ_HEAD(, defined_value) defined_values; 67 68 static const char * 69 defined_find(const char *name) 70 { 71 struct defined_value *d; 72 73 TAILQ_FOREACH(d, &defined_values, d_next) { 74 if (strcmp(d->d_name, name) == 0) 75 return (d->d_value); 76 } 77 78 return (NULL); 79 } 80 81 char * 82 defined_expand(const char *string) 83 { 84 const char *value; 85 char c, *expanded, *name; 86 int i, ret, before_len = 0, name_off = 0, name_len = 0, after_off = 0; 87 bool backslashed = false, bracketed = false; 88 89 expanded = checked_strdup(string); 90 91 for (i = 0; string[i] != '\0'; i++) { 92 c = string[i]; 93 if (c == '\\' && backslashed == false) { 94 backslashed = true; 95 continue; 96 } 97 if (backslashed) { 98 backslashed = false; 99 continue; 100 } 101 backslashed = false; 102 if (c != '$') 103 continue; 104 105 /* 106 * The 'before_len' variable contains the number 107 * of characters before the '$'. 108 */ 109 before_len = i; 110 assert(i + 1 < (int)strlen(string)); 111 if (string[i + 1] == '{') 112 bracketed = true; 113 114 if (string[i + 1] == '\0') { 115 log_warnx("truncated variable"); 116 return (NULL); 117 } 118 119 /* 120 * Skip '$'. 121 */ 122 i++; 123 124 if (bracketed) { 125 if (string[i + 1] == '\0') { 126 log_warnx("truncated variable"); 127 return (NULL); 128 } 129 130 /* 131 * Skip '{'. 132 */ 133 i++; 134 } 135 136 /* 137 * The 'name_off' variable contains the number 138 * of characters before the variable name, 139 * including the "$" or "${". 140 */ 141 name_off = i; 142 143 for (; string[i] != '\0'; i++) { 144 c = string[i]; 145 /* 146 * XXX: Decide on the set of characters that can be 147 * used in a variable name. 148 */ 149 if (isalnum(c) || c == '_') 150 continue; 151 152 /* 153 * End of variable name. 154 */ 155 if (bracketed) { 156 if (c != '}') 157 continue; 158 159 /* 160 * The 'after_off' variable contains the number 161 * of characters before the rest of the string, 162 * i.e. after the variable name. 163 */ 164 after_off = i + 1; 165 assert(i > 1); 166 assert(i - 1 > name_off); 167 name_len = i - name_off; 168 break; 169 } 170 171 after_off = i; 172 assert(i > 1); 173 assert(i > name_off); 174 name_len = i - name_off; 175 break; 176 } 177 178 name = strndup(string + name_off, name_len); 179 if (name == NULL) 180 log_err(1, "strndup"); 181 value = defined_find(name); 182 if (value == NULL) { 183 log_warnx("undefined variable ${%s}", name); 184 return (NULL); 185 } 186 187 /* 188 * Concatenate it back. 189 */ 190 ret = asprintf(&expanded, "%.*s%s%s", 191 before_len, string, value, string + after_off); 192 if (ret < 0) 193 log_err(1, "asprintf"); 194 195 //log_debugx("\"%s\" expanded to \"%s\"", string, expanded); 196 free(name); 197 198 /* 199 * Figure out where to start searching for next variable. 200 */ 201 string = expanded; 202 i = before_len + strlen(value); 203 backslashed = bracketed = false; 204 before_len = name_off = name_len = after_off = 0; 205 assert(i <= (int)strlen(string)); 206 } 207 208 if (before_len != 0 || name_off != 0 || name_len != 0 || after_off != 0) { 209 log_warnx("truncated variable"); 210 return (NULL); 211 } 212 213 return (expanded); 214 } 215 216 static void 217 defined_add(const char *name, const char *value) 218 { 219 struct defined_value *d; 220 const char *found; 221 222 found = defined_find(name); 223 if (found != NULL) 224 log_errx(1, "variable %s already defined", name); 225 226 log_debugx("defining variable %s=%s", name, value); 227 228 d = calloc(sizeof(*d), 1); 229 if (d == NULL) 230 log_err(1, "calloc"); 231 d->d_name = checked_strdup(name); 232 d->d_value = checked_strdup(value); 233 234 TAILQ_INSERT_TAIL(&defined_values, d, d_next); 235 } 236 237 void 238 defined_parse_and_add(char *def) 239 { 240 char *name, *value; 241 242 value = def; 243 name = strsep(&value, "="); 244 245 if (value == NULL || value[0] == '\0') 246 log_errx(1, "missing variable value"); 247 if (name == NULL || name[0] == '\0') 248 log_errx(1, "missing variable name"); 249 250 defined_add(name, value); 251 } 252 253 void 254 defined_init(void) 255 { 256 struct utsname name; 257 int error; 258 259 TAILQ_INIT(&defined_values); 260 261 error = uname(&name); 262 if (error != 0) 263 log_err(1, "uname"); 264 265 defined_add("ARCH", name.machine); 266 defined_add("CPU", name.machine); 267 defined_add("HOST", name.nodename); 268 defined_add("OSNAME", name.sysname); 269 defined_add("OSREL", name.release); 270 defined_add("OSVERS", name.version); 271 } 272