bootcfg.c revision 1.7
1 /* $NetBSD: bootcfg.c,v 1.7 2021/09/07 11:41:31 nia Exp $ */ 2 3 /*- 4 * Copyright (c) 2008 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #include <sys/types.h> 30 #include <sys/reboot.h> 31 32 #include <lib/libsa/stand.h> 33 #include <lib/libsa/bootcfg.h> 34 #include <lib/libkern/libkern.h> 35 36 #define MENUFORMAT_AUTO 0 37 #define MENUFORMAT_NUMBER 1 38 #define MENUFORMAT_LETTER 2 39 40 #define DEFAULT_FORMAT MENUFORMAT_AUTO 41 #define DEFAULT_TIMEOUT 10 42 43 struct bootcfg_def bootcfg_info; 44 45 void 46 bootcfg_do_noop(const char *cmd, char *arg) 47 { 48 /* noop, do nothing */ 49 } 50 51 /* 52 * This function parses a boot.cfg file in the root of the filesystem 53 * (if present) and populates the global boot configuration. 54 * 55 * The file consists of a number of lines each terminated by \n 56 * The lines are in the format keyword=value. There should not be spaces 57 * around the = sign. 58 * 59 * perform_bootcfg(conf, command, maxsz) 60 * 61 * conf Path to boot.cfg to be passed verbatim to open() 62 * 63 * command Pointer to a function that will be called when 64 * perform_bootcfg() encounters a key (command) it does not 65 * recognize. 66 * The command function is provided both the keyword and 67 * value parsed as arguments to the function. 68 * 69 * maxsz Limit the size of the boot.cfg perform_bootcfg() will parse. 70 * - If maxsz is < 0 boot.cfg will not be processed. 71 * - If maxsz is = 0 no limit will be imposed but parsing may 72 * fail due to platform or other constraints e.g. maximum 73 * segment size. 74 * - If 0 < maxsz and boot.cfg exceeds maxsz it will not be 75 * parsed, otherwise it will be parsed. 76 * 77 * The recognised keywords are: 78 * banner: text displayed instead of the normal welcome text 79 * menu: Descriptive text:command to use 80 * timeout: Timeout in seconds (overrides that set by installboot) 81 * default: the default menu option to use if Return is pressed 82 * consdev: the console device to use 83 * root: the root device to use 84 * format: how menu choices are displayed: (a)utomatic, (n)umbers or (l)etters 85 * clear: whether to clear the screen or not 86 * 87 * Example boot.cfg file: 88 * banner=Welcome to NetBSD 89 * banner=Please choose the boot type from the following menu 90 * menu=Boot NetBSD:boot netbsd 91 * menu=Boot into single user mode:boot netbsd -s 92 * menu=:boot hd1a:netbsd -cs 93 * menu=Goto boot comand line:prompt 94 * timeout=10 95 * consdev=com0 96 * default=1 97 */ 98 int 99 perform_bootcfg(const char *conf, bootcfg_command command, const off_t maxsz) 100 { 101 char *bc, *c; 102 int cmenu, cbanner; 103 ssize_t len, off, resid; 104 int fd, err; 105 struct stat st; 106 char *next, *key, *value, *v2; 107 108 /* clear bootcfg structure */ 109 memset(&bootcfg_info, 0, sizeof(bootcfg_info)); 110 111 /* set default timeout */ 112 bootcfg_info.timeout = DEFAULT_TIMEOUT; 113 114 /* automatically switch between letter and numbers on menu */ 115 bootcfg_info.menuformat = DEFAULT_FORMAT; 116 117 fd = open(conf, 0); 118 if (fd < 0) 119 return ENOENT; 120 121 err = fstat(fd, &st); 122 if (err == -1) { 123 /* file descriptor may not be backed by a libsa file-system */ 124 st.st_size = maxsz; 125 } 126 127 /* if a maximum size is being requested for the boot.cfg enforce it. */ 128 if (0 < maxsz && st.st_size > maxsz) { 129 close(fd); 130 return EFBIG; 131 } 132 133 bc = alloc((size_t)st.st_size + 1); 134 if (bc == NULL) { 135 printf("Could not allocate memory for boot configuration\n"); 136 close(fd); 137 return ENOMEM; 138 } 139 140 /* 141 * XXX original code, assumes error or eof return from read() 142 * results in the entire boot.cfg being buffered. 143 * - should bail out on read() failing. 144 * - assumption is made that the file size doesn't change between 145 * fstat() and read()ing. probably safe in this context 146 * arguably should check that reading the file won't overflow 147 * the storage anyway. 148 */ 149 off = 0; 150 resid = st.st_size; 151 do { 152 len = read(fd, bc + off, uimin(1024, resid)); 153 if (len <= 0) 154 break; 155 off += len; 156 resid -= len; 157 } while (len > 0 && resid > 0); 158 bc[off] = '\0'; 159 160 close(fd); 161 162 /* bc is now assumed to contain the whole boot.cfg file (see above) */ 163 164 cmenu = 0; 165 cbanner = 0; 166 for (c = bc; *c; c = next) { 167 key = c; 168 /* find end of line */ 169 for (; *c && *c != '\n'; c++) 170 /* zero terminate line on start of comment */ 171 if (*c == '#') 172 *c = 0; 173 /* zero terminate line */ 174 if (*(next = c)) 175 *next++ = 0; 176 /* Look for = separator between key and value */ 177 for (c = key; *c && *c != '='; c++) 178 continue; 179 /* Ignore lines with no key=value pair */ 180 if (*c == '\0') 181 continue; 182 183 /* zero terminate key which points to keyword */ 184 *c++ = 0; 185 value = c; 186 /* Look for end of line (or file) and zero terminate value */ 187 for (; *c && *c != '\n'; c++) 188 continue; 189 *c = 0; 190 191 if (!strncmp(key, "menu", 4)) { 192 /* 193 * Parse "menu=<description>:<command>". If the 194 * description is empty ("menu=:<command>)", 195 * then re-use the command as the description. 196 * Note that the command may contain embedded 197 * colons. 198 */ 199 if (cmenu >= BOOTCFG_MAXMENU) 200 continue; 201 bootcfg_info.desc[cmenu] = value; 202 for (v2 = value; *v2 && *v2 != ':'; v2++) 203 continue; 204 if (*v2) { 205 *v2++ = 0; 206 bootcfg_info.command[cmenu] = v2; 207 if (! *value) 208 bootcfg_info.desc[cmenu] = v2; 209 cmenu++; 210 } else { 211 /* No delimiter means invalid line */ 212 bootcfg_info.desc[cmenu] = NULL; 213 } 214 } else if (!strncmp(key, "banner", 6)) { 215 if (cbanner < BOOTCFG_MAXBANNER) 216 bootcfg_info.banner[cbanner++] = value; 217 } else if (!strncmp(key, "timeout", 7)) { 218 if (!isdigit(*value)) 219 bootcfg_info.timeout = -1; 220 else 221 bootcfg_info.timeout = atoi(value); 222 } else if (!strncmp(key, "default", 7)) { 223 bootcfg_info.def = atoi(value) - 1; 224 } else if (!strncmp(key, "consdev", 7)) { 225 bootcfg_info.consdev = value; 226 } else if (!strncmp(key, "root", 4)) { 227 bootcfg_info.root = value; 228 } else if (!strncmp(key, BOOTCFG_CMD_LOAD, 4)) { 229 command(BOOTCFG_CMD_LOAD, value); 230 } else if (!strncmp(key, "format", 6)) { 231 printf("value:%c\n", *value); 232 switch (*value) { 233 case 'a': 234 case 'A': 235 bootcfg_info.menuformat = MENUFORMAT_AUTO; 236 break; 237 238 case 'n': 239 case 'N': 240 case 'd': 241 case 'D': 242 bootcfg_info.menuformat = MENUFORMAT_NUMBER; 243 break; 244 245 case 'l': 246 case 'L': 247 bootcfg_info.menuformat = MENUFORMAT_LETTER; 248 break; 249 } 250 } else if (!strncmp(key, "clear", 5)) { 251 bootcfg_info.clear = !!atoi(value); 252 } else if (!strncmp(key, BOOTCFG_CMD_USERCONF, 8)) { 253 command(BOOTCFG_CMD_USERCONF, value); 254 } else { 255 command(key, value); 256 } 257 } 258 259 switch (bootcfg_info.menuformat) { 260 case MENUFORMAT_AUTO: 261 if (cmenu > 9 && bootcfg_info.timeout > 0) 262 bootcfg_info.menuformat = MENUFORMAT_LETTER; 263 else 264 bootcfg_info.menuformat = MENUFORMAT_NUMBER; 265 break; 266 267 case MENUFORMAT_NUMBER: 268 if (cmenu > 9 && bootcfg_info.timeout > 0) 269 cmenu = 9; 270 break; 271 } 272 273 bootcfg_info.nummenu = cmenu; 274 if (bootcfg_info.def < 0) 275 bootcfg_info.def = 0; 276 if (bootcfg_info.def >= cmenu) 277 bootcfg_info.def = cmenu - 1; 278 279 return 0; 280 } 281 282 void 283 print_bootcfg_banner(const char *bootprog_name, const char *bootprog_rev) 284 { 285 int n = 0; 286 287 if (bootcfg_info.banner[0]) { 288 for (; n < BOOTCFG_MAXBANNER && bootcfg_info.banner[n]; n++) 289 printf("%s\n", bootcfg_info.banner[n]); 290 return; 291 } 292 293 /* If the user has not specified a banner, print a default one. */ 294 295 printf("\n"); 296 printf(" \\\\-__,------,___.\n"); 297 printf(" \\\\ __,---` %s\n", bootprog_name); 298 printf(" \\\\ `---,_. Revision %s\n", bootprog_rev); 299 printf(" \\\\-,_____,.---`\n"); 300 printf(" \\\\\n"); 301 printf(" \\\\\n"); 302 printf(" \\\\\n\n"); 303 } 304
Indexes created Thu Sep 25 16:09:42 GMT 2025