1 /* 2 * petal.c - https daemon that is small and beautiful. 3 * 4 * Copyright (c) 2010, NLnet Labs. All rights reserved. 5 * 6 * This software is open source. 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 * 12 * Redistributions of source code must retain the above copyright notice, 13 * this list of conditions and the following disclaimer. 14 * 15 * Redistributions in binary form must reproduce the above copyright notice, 16 * this list of conditions and the following disclaimer in the documentation 17 * and/or other materials provided with the distribution. 18 * 19 * Neither the name of the NLNET LABS nor the names of its contributors may 20 * be used to endorse or promote products derived from this software without 21 * specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 26 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 27 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 30 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35 36 /** 37 * \file 38 * 39 * HTTP1.1/SSL server. 40 */ 41 42 #include "config.h" 43 #ifdef HAVE_GETOPT_H 44 #include <getopt.h> 45 #endif 46 #ifdef HAVE_OPENSSL_SSL_H 47 #include <openssl/ssl.h> 48 #endif 49 #ifdef HAVE_OPENSSL_ERR_H 50 #include <openssl/err.h> 51 #endif 52 #ifdef HAVE_OPENSSL_RAND_H 53 #include <openssl/rand.h> 54 #endif 55 #include <openssl/x509.h> 56 #include <openssl/pem.h> 57 #include <ctype.h> 58 #include <signal.h> 59 #if defined(UNBOUND_ALLOC_LITE) || defined(UNBOUND_ALLOC_STATS) 60 #ifdef malloc 61 #undef malloc 62 #endif 63 #ifdef free 64 #undef free 65 #endif 66 #endif /* alloc lite or alloc stats */ 67 68 /** verbosity for this application */ 69 static int verb = 0; 70 71 /** Give petal usage, and exit (1). */ 72 static void 73 usage(void) 74 { 75 printf("Usage: petal [opts]\n"); 76 printf(" https daemon serves files from ./'host'/filename\n"); 77 printf(" (no hostname: from the 'default' directory)\n"); 78 printf("-a addr bind to this address, 127.0.0.1\n"); 79 printf("-p port port number, default 443\n"); 80 printf("-k keyfile SSL private key file (PEM), petal.key\n"); 81 printf("-c certfile SSL certificate file (PEM), petal.pem\n"); 82 printf("-v more verbose\n"); 83 printf("-h show this usage help\n"); 84 printf("Version %s\n", PACKAGE_VERSION); 85 printf("BSD licensed, see LICENSE in source package for details.\n"); 86 printf("Report bugs to %s\n", PACKAGE_BUGREPORT); 87 exit(1); 88 } 89 90 /** fatal exit */ 91 static void print_exit(const char* str) {printf("error %s\n", str); exit(1);} 92 /** print errno */ 93 static void log_errno(const char* str) 94 {printf("error %s: %s\n", str, strerror(errno));} 95 96 /** parse a text IP address into a sockaddr */ 97 static int 98 parse_ip_addr(char* str, int port, struct sockaddr_storage* ret, socklen_t* l) 99 { 100 socklen_t len = 0; 101 struct sockaddr_storage* addr = NULL; 102 struct sockaddr_in6 a6; 103 struct sockaddr_in a; 104 uint16_t p = (uint16_t)port; 105 int fam = 0; 106 memset(&a6, 0, sizeof(a6)); 107 memset(&a, 0, sizeof(a)); 108 109 if(inet_pton(AF_INET6, str, &a6.sin6_addr) > 0) { 110 /* it is an IPv6 */ 111 fam = AF_INET6; 112 a6.sin6_family = AF_INET6; 113 a6.sin6_port = (in_port_t)htons(p); 114 addr = (struct sockaddr_storage*)&a6; 115 len = (socklen_t)sizeof(struct sockaddr_in6); 116 } 117 if(inet_pton(AF_INET, str, &a.sin_addr) > 0) { 118 /* it is an IPv4 */ 119 fam = AF_INET; 120 a.sin_family = AF_INET; 121 a.sin_port = (in_port_t)htons(p); 122 addr = (struct sockaddr_storage*)&a; 123 len = (socklen_t)sizeof(struct sockaddr_in); 124 } 125 if(!len) print_exit("cannot parse addr"); 126 *l = len; 127 memmove(ret, addr, len); 128 return fam; 129 } 130 131 /** close the fd */ 132 static void 133 fd_close(int fd) 134 { 135 #ifndef USE_WINSOCK 136 close(fd); 137 #else 138 closesocket(fd); 139 #endif 140 } 141 142 /** 143 * Read one line from SSL 144 * zero terminates. 145 * skips "\r\n" (but not copied to buf). 146 * @param ssl: the SSL connection to read from (blocking). 147 * @param buf: buffer to return line in. 148 * @param len: size of the buffer. 149 * @return 0 on error, 1 on success. 150 */ 151 static int 152 read_ssl_line(SSL* ssl, char* buf, size_t len) 153 { 154 size_t n = 0; 155 int r; 156 int endnl = 0; 157 while(1) { 158 if(n >= len) { 159 if(verb) printf("line too long\n"); 160 return 0; 161 } 162 if((r = SSL_read(ssl, buf+n, 1)) <= 0) { 163 if(SSL_get_error(ssl, r) == SSL_ERROR_ZERO_RETURN) { 164 /* EOF */ 165 break; 166 } 167 if(verb) printf("could not SSL_read\n"); 168 return 0; 169 } 170 if(endnl && buf[n] == '\n') { 171 break; 172 } else if(endnl) { 173 /* bad data */ 174 if(verb) printf("error: stray linefeeds\n"); 175 return 0; 176 } else if(buf[n] == '\r') { 177 /* skip \r, and also \n on the wire */ 178 endnl = 1; 179 continue; 180 } else if(buf[n] == '\n') { 181 /* skip the \n, we are done */ 182 break; 183 } else n++; 184 } 185 buf[n] = 0; 186 return 1; 187 } 188 189 /** process one http header */ 190 static int 191 process_one_header(char* buf, char* file, size_t flen, char* host, size_t hlen, 192 int* vs) 193 { 194 if(strncasecmp(buf, "GET ", 4) == 0) { 195 char* e = strstr(buf, " HTTP/1.1"); 196 if(!e) e = strstr(buf, " http/1.1"); 197 if(!e) { 198 e = strstr(buf, " HTTP/1.0"); 199 if(!e) e = strstr(buf, " http/1.0"); 200 if(!e) e = strrchr(buf, ' '); 201 if(!e) e = strrchr(buf, '\t'); 202 if(e) *vs = 10; 203 } 204 if(e) *e = 0; 205 if(strlen(buf) < 4) return 0; 206 (void)strlcpy(file, buf+4, flen); 207 } else if(strncasecmp(buf, "Host: ", 6) == 0) { 208 (void)strlcpy(host, buf+6, hlen); 209 } 210 return 1; 211 } 212 213 /** read http headers and process them */ 214 static int 215 read_http_headers(SSL* ssl, char* file, size_t flen, char* host, size_t hlen, 216 int* vs) 217 { 218 char buf[1024]; 219 file[0] = 0; 220 host[0] = 0; 221 while(read_ssl_line(ssl, buf, sizeof(buf))) { 222 if(verb>=2) printf("read: %s\n", buf); 223 if(buf[0] == 0) 224 return 1; 225 if(!process_one_header(buf, file, flen, host, hlen, vs)) 226 return 0; 227 } 228 return 0; 229 } 230 231 /** setup SSL context */ 232 static SSL_CTX* 233 setup_ctx(char* key, char* cert) 234 { 235 SSL_CTX* ctx = SSL_CTX_new(SSLv23_server_method()); 236 if(!ctx) print_exit("out of memory"); 237 #if SSL_OP_NO_SSLv2 != 0 238 (void)SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv2); 239 #endif 240 (void)SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv3); 241 if(!SSL_CTX_use_certificate_chain_file(ctx, cert)) 242 print_exit("cannot read cert"); 243 if(!SSL_CTX_use_PrivateKey_file(ctx, key, SSL_FILETYPE_PEM)) 244 print_exit("cannot read key"); 245 if(!SSL_CTX_check_private_key(ctx)) 246 print_exit("private key is not correct"); 247 #if HAVE_DECL_SSL_CTX_SET_ECDH_AUTO 248 if (!SSL_CTX_set_ecdh_auto(ctx,1)) 249 if(verb>=1) printf("failed to set_ecdh_auto, not enabling ECDHE\n"); 250 #elif defined(USE_ECDSA) 251 if(1) { 252 EC_KEY *ecdh = EC_KEY_new_by_curve_name (NID_X9_62_prime256v1); 253 if (!ecdh) { 254 if(verb>=1) printf("could not find p256, not enabling ECDHE\n"); 255 } else { 256 if (1 != SSL_CTX_set_tmp_ecdh (ctx, ecdh)) { 257 if(verb>=1) printf("Error in SSL_CTX_set_tmp_ecdh, not enabling ECDHE\n"); 258 } 259 EC_KEY_free(ecdh); 260 } 261 } 262 #endif 263 if(!SSL_CTX_load_verify_locations(ctx, cert, NULL)) 264 print_exit("cannot load cert verify locations"); 265 return ctx; 266 } 267 268 /** setup listening TCP */ 269 static int 270 setup_fd(char* addr, int port) 271 { 272 struct sockaddr_storage ad; 273 socklen_t len; 274 int fd; 275 int c = 1; 276 int fam = parse_ip_addr(addr, port, &ad, &len); 277 fd = socket(fam, SOCK_STREAM, 0); 278 if(fd == -1) { 279 log_errno("socket"); 280 return -1; 281 } 282 if(setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, 283 (void*)&c, (socklen_t) sizeof(int)) < 0) { 284 log_errno("setsockopt(SOL_SOCKET, SO_REUSEADDR)"); 285 } 286 if(bind(fd, (struct sockaddr*)&ad, len) == -1) { 287 log_errno("bind"); 288 fd_close(fd); 289 return -1; 290 } 291 if(listen(fd, 5) == -1) { 292 log_errno("listen"); 293 fd_close(fd); 294 return -1; 295 } 296 return fd; 297 } 298 299 /** setup SSL connection to the client */ 300 static SSL* 301 setup_ssl(int s, SSL_CTX* ctx) 302 { 303 SSL* ssl = SSL_new(ctx); 304 if(!ssl) return NULL; 305 SSL_set_accept_state(ssl); 306 (void)SSL_set_mode(ssl, (long)SSL_MODE_AUTO_RETRY); 307 if(!SSL_set_fd(ssl, s)) { 308 SSL_free(ssl); 309 return NULL; 310 } 311 return ssl; 312 } 313 314 /** check a file name for safety */ 315 static int 316 file_name_is_safe(char* s) 317 { 318 size_t l = strlen(s); 319 if(s[0] != '/') 320 return 0; /* must start with / */ 321 if(strstr(s, "/../")) 322 return 0; /* no updirs in URL */ 323 if(l>=3 && s[l-1]=='.' && s[l-2]=='.' && s[l-3]=='/') 324 return 0; /* ends with /.. */ 325 return 1; 326 } 327 328 /** adjust host */ 329 static void 330 adjust_host(char* host) 331 { 332 size_t i, len; 333 /* remove a port number if present */ 334 if(strrchr(host, ':')) 335 *strrchr(host, ':') = 0; 336 /* lowercase */ 337 len = strlen(host); 338 for(i=0; i<len; i++) 339 host[i] = tolower((unsigned char)host[i]); 340 } 341 342 /** adjust filename */ 343 static void 344 adjust_file(char* file) 345 { 346 size_t i, len; 347 len = strlen(file); 348 for(i=0; i<len; i++) 349 file[i] = tolower((unsigned char)file[i]); 350 } 351 352 /** check a host name for safety */ 353 static int 354 host_name_is_safe(char* s) 355 { 356 if(strchr(s, '/')) 357 return 0; 358 if(strcmp(s, "..") == 0) 359 return 0; 360 if(strcmp(s, ".") == 0) 361 return 0; 362 return 1; 363 } 364 365 /** provide file in whole transfer */ 366 static void 367 provide_file_10(SSL* ssl, char* fname) 368 { 369 char* buf, *at; 370 size_t len, avail, header_reserve=1024; 371 FILE* in = fopen(fname, 372 #ifndef USE_WINSOCK 373 "r" 374 #else 375 "rb" 376 #endif 377 ); 378 size_t r; 379 const char* rcode = "200 OK"; 380 if(!in) { 381 char hdr[1024]; 382 rcode = "404 File not found"; 383 snprintf(hdr, sizeof(hdr), "HTTP/1.1 %s\r\n\r\n", rcode); 384 r = strlen(hdr); 385 if(SSL_write(ssl, hdr, (int)r) <= 0) { 386 /* write failure */ 387 } 388 return; 389 } 390 fseek(in, 0, SEEK_END); 391 len = (size_t)ftell(in); 392 fseek(in, 0, SEEK_SET); 393 /* plus some space for the header */ 394 buf = (char*)malloc(len+header_reserve); 395 if(!buf) { 396 fclose(in); 397 return; 398 } 399 avail = len+header_reserve; 400 at = buf; 401 snprintf(at, avail, "HTTP/1.1 %s\r\n", rcode); 402 r = strlen(at); 403 at += r; 404 avail -= r; 405 snprintf(at, avail, "Server: petal/%s\r\n", PACKAGE_VERSION); 406 r = strlen(at); 407 at += r; 408 avail -= r; 409 snprintf(at, avail, "Content-Length: %u\r\n", (unsigned)len); 410 r = strlen(at); 411 at += r; 412 avail -= r; 413 snprintf(at, avail, "\r\n"); 414 r = strlen(at); 415 at += r; 416 avail -= r; 417 if(avail < len) { /* robust */ 418 free(buf); 419 fclose(in); 420 return; 421 } 422 if(fread(at, 1, len, in) != len) { 423 free(buf); 424 fclose(in); 425 return; 426 } 427 fclose(in); 428 at += len; 429 /* avail -= len; unused */ 430 if(SSL_write(ssl, buf, at-buf) <= 0) { 431 /* write failure */ 432 } 433 free(buf); 434 } 435 436 /** provide file over SSL, chunked encoding */ 437 static void 438 provide_file_chunked(SSL* ssl, char* fname) 439 { 440 char buf[16384]; 441 char* tmpbuf = NULL; 442 char* at = buf; 443 size_t avail = sizeof(buf); 444 size_t r; 445 FILE* in = fopen(fname, 446 #ifndef USE_WINSOCK 447 "r" 448 #else 449 "rb" 450 #endif 451 ); 452 const char* rcode = "200 OK"; 453 if(!in) { 454 rcode = "404 File not found"; 455 } 456 457 /* print headers */ 458 snprintf(at, avail, "HTTP/1.1 %s\r\n", rcode); 459 r = strlen(at); 460 at += r; 461 avail -= r; 462 snprintf(at, avail, "Server: petal/%s\r\n", PACKAGE_VERSION); 463 r = strlen(at); 464 at += r; 465 avail -= r; 466 snprintf(at, avail, "Transfer-Encoding: chunked\r\n"); 467 r = strlen(at); 468 at += r; 469 avail -= r; 470 snprintf(at, avail, "Connection: close\r\n"); 471 r = strlen(at); 472 at += r; 473 avail -= r; 474 snprintf(at, avail, "\r\n"); 475 r = strlen(at); 476 at += r; 477 avail -= r; 478 if(avail < 16) { /* robust */ 479 if(in) fclose(in); 480 return; 481 } 482 483 do { 484 size_t red; 485 free(tmpbuf); 486 tmpbuf = malloc(avail-16); 487 if(!tmpbuf) 488 break; 489 /* read chunk; space-16 for xxxxCRLF..CRLF0CRLFCRLF (3 spare)*/ 490 red = in?fread(tmpbuf, 1, avail-16, in):0; 491 /* prepare chunk */ 492 snprintf(at, avail, "%x\r\n", (unsigned)red); 493 r = strlen(at); 494 if(verb >= 3) 495 {printf("chunk len %x\n", (unsigned)red); fflush(stdout);} 496 at += r; 497 avail -= r; 498 if(red != 0) { 499 if(red > avail) break; /* robust */ 500 memmove(at, tmpbuf, red); 501 at += red; 502 avail -= red; 503 snprintf(at, avail, "\r\n"); 504 r = strlen(at); 505 at += r; 506 avail -= r; 507 } 508 if(in && feof(in) && red != 0) { 509 snprintf(at, avail, "0\r\n"); 510 r = strlen(at); 511 at += r; 512 avail -= r; 513 } 514 if(!in || feof(in)) { 515 snprintf(at, avail, "\r\n"); 516 r = strlen(at); 517 at += r; 518 /* avail -= r; unused */ 519 } 520 /* send chunk */ 521 if(SSL_write(ssl, buf, at-buf) <= 0) { 522 /* SSL error */ 523 break; 524 } 525 526 /* setup for next chunk */ 527 at = buf; 528 avail = sizeof(buf); 529 } while(in && !feof(in) && !ferror(in)); 530 531 free(tmpbuf); 532 if(in) fclose(in); 533 } 534 535 /** provide service to the ssl descriptor */ 536 static void 537 service_ssl(SSL* ssl, struct sockaddr_storage* from, socklen_t falen) 538 { 539 char file[1024]; 540 char host[1024]; 541 char combined[2048]; 542 int vs = 11; 543 if(!read_http_headers(ssl, file, sizeof(file), host, sizeof(host), 544 &vs)) 545 return; 546 if(host[0] != 0) adjust_host(host); 547 if(file[0] != 0) adjust_file(file); 548 if(host[0] == 0 || !host_name_is_safe(host)) 549 (void)strlcpy(host, "default", sizeof(host)); 550 if(!file_name_is_safe(file)) { 551 return; 552 } 553 snprintf(combined, sizeof(combined), "%s%s", host, file); 554 if(verb) { 555 char out[100]; 556 void* a = &((struct sockaddr_in*)from)->sin_addr; 557 if(falen != (socklen_t)sizeof(struct sockaddr_in)) 558 a = &((struct sockaddr_in6*)from)->sin6_addr; 559 out[0]=0; 560 (void)inet_ntop((int)((struct sockaddr_in*)from)->sin_family, 561 a, out, (socklen_t)sizeof(out)); 562 printf("%s requests %s\n", out, combined); 563 fflush(stdout); 564 } 565 if(vs == 10) 566 provide_file_10(ssl, combined); 567 else provide_file_chunked(ssl, combined); 568 } 569 570 /** provide ssl service */ 571 static void 572 do_service(char* addr, int port, char* key, char* cert) 573 { 574 SSL_CTX* sslctx = setup_ctx(key, cert); 575 int fd = setup_fd(addr, port); 576 int go = 1; 577 if(fd == -1) print_exit("could not setup sockets"); 578 if(verb) {printf("petal start\n"); fflush(stdout);} 579 while(go) { 580 struct sockaddr_storage from; 581 socklen_t flen = (socklen_t)sizeof(from); 582 int s; 583 memset(&from, 0, sizeof(from)); 584 s = accept(fd, (struct sockaddr*)&from, &flen); 585 if(verb) fflush(stdout); 586 if(s != -1) { 587 SSL* ssl = setup_ssl(s, sslctx); 588 if(verb) fflush(stdout); 589 if(ssl) { 590 service_ssl(ssl, &from, flen); 591 if(verb) fflush(stdout); 592 SSL_shutdown(ssl); 593 SSL_free(ssl); 594 } 595 fd_close(s); 596 } else if (verb >=2) log_errno("accept"); 597 if(verb) fflush(stdout); 598 } 599 /* if we get a kill signal, the process dies and the OS reaps us */ 600 if(verb) printf("petal end\n"); 601 fd_close(fd); 602 SSL_CTX_free(sslctx); 603 } 604 605 /** getopt global, in case header files fail to declare it. */ 606 extern int optind; 607 /** getopt global, in case header files fail to declare it. */ 608 extern char* optarg; 609 610 /** Main routine for petal */ 611 int main(int argc, char* argv[]) 612 { 613 int c; 614 int port = 443; 615 char* addr = "127.0.0.1", *key = "petal.key", *cert = "petal.pem"; 616 #ifdef USE_WINSOCK 617 WSADATA wsa_data; 618 if((c=WSAStartup(MAKEWORD(2,2), &wsa_data)) != 0) 619 { printf("WSAStartup failed\n"); exit(1); } 620 atexit((void (*)(void))WSACleanup); 621 #endif 622 623 /* parse the options */ 624 while( (c=getopt(argc, argv, "a:c:k:hp:v")) != -1) { 625 switch(c) { 626 case 'a': 627 addr = optarg; 628 break; 629 case 'c': 630 cert = optarg; 631 break; 632 case 'k': 633 key = optarg; 634 break; 635 case 'p': 636 port = atoi(optarg); 637 break; 638 case 'v': 639 verb++; 640 break; 641 case '?': 642 case 'h': 643 default: 644 usage(); 645 } 646 } 647 argc -= optind; 648 /* argv += optind; not using further arguments */ 649 if(argc != 0) 650 usage(); 651 652 #ifdef SIGPIPE 653 (void)signal(SIGPIPE, SIG_IGN); 654 #endif 655 #ifdef HAVE_ERR_LOAD_CRYPTO_STRINGS 656 ERR_load_crypto_strings(); 657 #endif 658 #if OPENSSL_VERSION_NUMBER < 0x10100000 || !defined(HAVE_OPENSSL_INIT_SSL) 659 ERR_load_SSL_strings(); 660 #endif 661 #if OPENSSL_VERSION_NUMBER < 0x10100000 || !defined(HAVE_OPENSSL_INIT_CRYPTO) 662 # ifndef S_SPLINT_S 663 OpenSSL_add_all_algorithms(); 664 # endif 665 #else 666 OPENSSL_init_crypto(OPENSSL_INIT_ADD_ALL_CIPHERS 667 | OPENSSL_INIT_ADD_ALL_DIGESTS 668 | OPENSSL_INIT_LOAD_CRYPTO_STRINGS, NULL); 669 #endif 670 #if OPENSSL_VERSION_NUMBER < 0x10100000 || !defined(HAVE_OPENSSL_INIT_SSL) 671 (void)SSL_library_init(); 672 #else 673 (void)OPENSSL_init_ssl(OPENSSL_INIT_LOAD_SSL_STRINGS, NULL); 674 #endif 675 676 do_service(addr, port, key, cert); 677 678 #ifdef HAVE_CRYPTO_CLEANUP_ALL_EX_DATA 679 CRYPTO_cleanup_all_ex_data(); 680 #endif 681 #ifdef HAVE_ERR_FREE_STRINGS 682 ERR_free_strings(); 683 #endif 684 return 0; 685 } 686