1 /* 2 * dovend.c : Inserts all but the first few vendor options. 3 */ 4 5 #include <sys/types.h> 6 7 #include <netinet/in.h> 8 #include <arpa/inet.h> /* inet_ntoa */ 9 10 #include <stdlib.h> 11 #include <stdio.h> 12 #include <string.h> 13 #include <errno.h> 14 #include <syslog.h> 15 16 #ifndef USE_BFUNCS 17 # include <memory.h> 18 /* Yes, memcpy is OK here (no overlapped copies). */ 19 # define bcopy(a,b,c) memcpy(b,a,c) 20 # define bzero(p,l) memset(p,0,l) 21 # define bcmp(a,b,c) memcmp(a,b,c) 22 # define index strchr 23 #endif 24 25 #include "bootp.h" 26 #include "bootpd.h" 27 #include "report.h" 28 #include "dovend.h" 29 30 #ifdef __STDC__ 31 #define P(args) args 32 #else 33 #define P(args) () 34 #endif 35 36 PRIVATE int insert_generic P((struct shared_bindata *, byte **, int *)); 37 38 /* 39 * Insert the 2nd part of the options into an option buffer. 40 * Return amount of space used. 41 * 42 * This inserts everything EXCEPT: 43 * magic cookie, subnet mask, gateway, bootsize, extension file 44 * Those are handled separately (in bootpd.c) to allow this function 45 * to be shared between bootpd and bootpef. 46 * 47 * When an "extension file" is in use, the options inserted by 48 * this function go into the exten_file, not the bootp response. 49 */ 50 51 int 52 dovend_rfc1497(hp, buf, len) 53 struct host *hp; 54 byte *buf; 55 int len; 56 { 57 int bytesleft = len; 58 byte *vp = buf; 59 char *tmpstr; 60 61 static char noroom[] = "%s: No room for \"%s\" option"; 62 #define NEED(LEN, MSG) do \ 63 if (bytesleft < (LEN)) { \ 64 report(LOG_NOTICE, noroom, \ 65 hp->hostname->string, MSG); \ 66 return (vp - buf); \ 67 } while (0) 68 69 /* 70 * Note that the following have already been inserted: 71 * magic_cookie, subnet_mask, gateway, bootsize 72 * 73 * The remaining options are inserted in order of importance. 74 * (Of course the importance of each is a matter of opinion.) 75 * The option insertion order should probably be configurable. 76 * 77 * This is the order used in the NetBSD version. Can anyone 78 * explain why the time_offset and swap_server are first? 79 * Also, why is the hostname so far down the list? -gwr 80 */ 81 82 if (hp->flags.time_offset) { 83 NEED(6, "to"); 84 *vp++ = TAG_TIME_OFFSET;/* -1 byte */ 85 *vp++ = 4; /* -1 byte */ 86 insert_u_long(htonl(hp->time_offset), &vp); /* -4 bytes */ 87 bytesleft -= 6; 88 } 89 /* 90 * swap server, root path, dump path 91 */ 92 if (hp->flags.swap_server) { 93 NEED(6, "sw"); 94 /* There is just one SWAP_SERVER, so it is not an iplist. */ 95 *vp++ = TAG_SWAP_SERVER;/* -1 byte */ 96 *vp++ = 4; /* -1 byte */ 97 insert_u_long(hp->swap_server.s_addr, &vp); /* -4 bytes */ 98 bytesleft -= 6; /* Fix real count */ 99 } 100 if (hp->flags.root_path) { 101 /* 102 * Check for room for root_path. Add 2 to account for 103 * TAG_ROOT_PATH and length. 104 */ 105 len = strlen(hp->root_path->string); 106 NEED((len + 2), "rp"); 107 *vp++ = TAG_ROOT_PATH; 108 *vp++ = (byte) (len & 0xFF); 109 bcopy(hp->root_path->string, vp, len); 110 vp += len; 111 bytesleft -= len + 2; 112 } 113 if (hp->flags.dump_file) { 114 /* 115 * Check for room for dump_file. Add 2 to account for 116 * TAG_DUMP_FILE and length. 117 */ 118 len = strlen(hp->dump_file->string); 119 NEED((len + 2), "df"); 120 *vp++ = TAG_DUMP_FILE; 121 *vp++ = (byte) (len & 0xFF); 122 bcopy(hp->dump_file->string, vp, len); 123 vp += len; 124 bytesleft -= len + 2; 125 } 126 /* 127 * DNS server and domain 128 */ 129 if (hp->flags.domain_server) { 130 if (insert_ip(TAG_DOMAIN_SERVER, 131 hp->domain_server, 132 &vp, &bytesleft)) 133 NEED(8, "ds"); 134 } 135 if (hp->flags.domain_name) { 136 /* 137 * Check for room for domain_name. Add 2 to account for 138 * TAG_DOMAIN_NAME and length. 139 */ 140 len = strlen(hp->domain_name->string); 141 NEED((len + 2), "dn"); 142 *vp++ = TAG_DOMAIN_NAME; 143 *vp++ = (byte) (len & 0xFF); 144 bcopy(hp->domain_name->string, vp, len); 145 vp += len; 146 bytesleft -= len + 2; 147 } 148 /* 149 * NIS (YP) server and domain 150 */ 151 if (hp->flags.nis_server) { 152 if (insert_ip(TAG_NIS_SERVER, 153 hp->nis_server, 154 &vp, &bytesleft)) 155 NEED(8, "ds"); 156 } 157 if (hp->flags.nis_domain) { 158 /* 159 * Check for room for nis_domain. Add 2 to account for 160 * TAG_NIS_DOMAIN and length. 161 */ 162 len = strlen(hp->nis_domain->string); 163 NEED((len + 2), "dn"); 164 *vp++ = TAG_NIS_DOMAIN; 165 *vp++ = (byte) (len & 0xFF); 166 bcopy(hp->nis_domain->string, vp, len); 167 vp += len; 168 bytesleft -= len + 2; 169 } 170 /* IEN 116 name server */ 171 if (hp->flags.name_server) { 172 if (insert_ip(TAG_NAME_SERVER, 173 hp->name_server, 174 &vp, &bytesleft)) 175 NEED(8, "ns"); 176 } 177 if (hp->flags.rlp_server) { 178 if (insert_ip(TAG_RLP_SERVER, 179 hp->rlp_server, 180 &vp, &bytesleft)) 181 NEED(8, "rl"); 182 } 183 /* Time server (RFC 868) */ 184 if (hp->flags.time_server) { 185 if (insert_ip(TAG_TIME_SERVER, 186 hp->time_server, 187 &vp, &bytesleft)) 188 NEED(8, "ts"); 189 } 190 /* NTP (time) Server (RFC 1129) */ 191 if (hp->flags.ntp_server) { 192 if (insert_ip(TAG_NTP_SERVER, 193 hp->ntp_server, 194 &vp, &bytesleft)) 195 NEED(8, "ts"); 196 } 197 /* 198 * I wonder: If the hostname were "promoted" into the BOOTP 199 * response part, might these "extension" files possibly be 200 * shared between several clients? 201 * 202 * Also, why not just use longer BOOTP packets with all the 203 * additional length used as option data. This bootpd version 204 * already supports that feature by replying with the same 205 * packet length as the client request packet. -gwr 206 */ 207 if (hp->flags.name_switch && hp->flags.send_name) { 208 /* 209 * Check for room for hostname. Add 2 to account for 210 * TAG_HOST_NAME and length. 211 */ 212 len = strlen(hp->hostname->string); 213 #if 0 214 /* 215 * XXX - Too much magic. The user can always set the hostname 216 * to the short version in the bootptab file. -gwr 217 */ 218 if ((len + 2) > bytesleft) { 219 /* 220 * Not enough room for full (domain-qualified) hostname, try 221 * stripping it down to just the first field (host). 222 */ 223 tmpstr = hp->hostname->string; 224 len = 0; 225 while (*tmpstr && (*tmpstr != '.')) { 226 tmpstr++; 227 len++; 228 } 229 } 230 #endif 231 NEED((len + 2), "hn"); 232 *vp++ = TAG_HOST_NAME; 233 *vp++ = (byte) (len & 0xFF); 234 bcopy(hp->hostname->string, vp, len); 235 vp += len; 236 bytesleft -= len + 2; 237 } 238 /* 239 * The rest of these are less important, so they go last. 240 */ 241 if (hp->flags.lpr_server) { 242 if (insert_ip(TAG_LPR_SERVER, 243 hp->lpr_server, 244 &vp, &bytesleft)) 245 NEED(8, "lp"); 246 } 247 if (hp->flags.cookie_server) { 248 if (insert_ip(TAG_COOKIE_SERVER, 249 hp->cookie_server, 250 &vp, &bytesleft)) 251 NEED(8, "cs"); 252 } 253 if (hp->flags.log_server) { 254 if (insert_ip(TAG_LOG_SERVER, 255 hp->log_server, 256 &vp, &bytesleft)) 257 NEED(8, "lg"); 258 } 259 /* 260 * XXX - Add new tags here (to insert options) 261 */ 262 if (hp->flags.generic) { 263 if (insert_generic(hp->generic, &vp, &bytesleft)) 264 NEED(64, "(generic)"); 265 } 266 /* 267 * The end marker is inserted by the caller. 268 */ 269 return (vp - buf); 270 #undef NEED 271 } /* dovend_rfc1497 */ 272 273 274 275 /* 276 * Insert a tag value, a length value, and a list of IP addresses into the 277 * memory buffer indirectly pointed to by "dest". "tag" is the RFC1048 tag 278 * number to use, "iplist" is a pointer to a list of IP addresses 279 * (struct in_addr_list), and "bytesleft" points to an integer which 280 * indicates the size of the "dest" buffer. 281 * 282 * Return zero if everything fits. 283 * 284 * This is used to fill the vendor-specific area of a bootp packet in 285 * conformance to RFC1048. 286 */ 287 288 int 289 insert_ip(tag, iplist, dest, bytesleft) 290 byte tag; 291 struct in_addr_list *iplist; 292 byte **dest; 293 int *bytesleft; 294 { 295 struct in_addr *addrptr; 296 unsigned addrcount = 1; 297 byte *d; 298 299 if (iplist == NULL) 300 return (0); 301 302 if (*bytesleft >= 6) { 303 d = *dest; /* Save pointer for later */ 304 **dest = tag; 305 (*dest) += 2; 306 (*bytesleft) -= 2; /* Account for tag and length */ 307 addrptr = iplist->addr; 308 addrcount = iplist->addrcount; 309 while ((*bytesleft >= 4) && (addrcount > 0)) { 310 insert_u_long(addrptr->s_addr, dest); 311 addrptr++; 312 addrcount--; 313 (*bytesleft) -= 4; /* Four bytes per address */ 314 } 315 d[1] = (byte) ((*dest - d - 2) & 0xFF); 316 } 317 return (addrcount); 318 } 319 320 321 322 /* 323 * Insert generic data into a bootp packet. The data is assumed to already 324 * be in RFC1048 format. It is inserted using a first-fit algorithm which 325 * attempts to insert as many tags as possible. Tags and data which are 326 * too large to fit are skipped; any remaining tags are tried until they 327 * have all been exhausted. 328 * Return zero if everything fits. 329 */ 330 331 static int 332 insert_generic(gendata, buff, bytesleft) 333 struct shared_bindata *gendata; 334 byte **buff; 335 int *bytesleft; 336 { 337 byte *srcptr; 338 int length, numbytes; 339 int skipped = 0; 340 341 if (gendata == NULL) 342 return (0); 343 344 srcptr = gendata->data; 345 length = gendata->length; 346 while ((length > 0) && (*bytesleft > 0)) { 347 switch (*srcptr) { 348 case TAG_END: 349 length = 0; /* Force an exit on next iteration */ 350 break; 351 case TAG_PAD: 352 *(*buff)++ = *srcptr++; 353 (*bytesleft)--; 354 length--; 355 break; 356 default: 357 numbytes = srcptr[1] + 2; 358 if (*bytesleft < numbytes) 359 skipped += numbytes; 360 else { 361 bcopy(srcptr, *buff, numbytes); 362 (*buff) += numbytes; 363 (*bytesleft) -= numbytes; 364 } 365 srcptr += numbytes; 366 length -= numbytes; 367 break; 368 } 369 } /* while */ 370 return (skipped); 371 } 372 373 /* 374 * Insert the unsigned long "value" into memory starting at the byte 375 * pointed to by the byte pointer (*dest). (*dest) is updated to 376 * point to the next available byte. 377 * 378 * Since it is desirable to internally store network addresses in network 379 * byte order (in struct in_addr's), this routine expects longs to be 380 * passed in network byte order. 381 * 382 * However, due to the nature of the main algorithm, the long must be in 383 * host byte order, thus necessitating the use of ntohl() first. 384 */ 385 386 void 387 insert_u_long(value, dest) 388 u_int32 value; 389 byte **dest; 390 { 391 byte *temp; 392 int n; 393 394 value = ntohl(value); /* Must use host byte order here */ 395 temp = (*dest += 4); 396 for (n = 4; n > 0; n--) { 397 *--temp = (byte) (value & 0xFF); 398 value >>= 8; 399 } 400 /* Final result is network byte order */ 401 } 402 403 /* 404 * Local Variables: 405 * tab-width: 4 406 * c-indent-level: 4 407 * c-argdecl-indent: 4 408 * c-continued-statement-offset: 4 409 * c-continued-brace-offset: -4 410 * c-label-offset: -4 411 * c-brace-offset: 0 412 * End: 413 */ 414