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