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 (void)SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv2); 238 (void)SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv3); 239 if(!SSL_CTX_use_certificate_chain_file(ctx, cert)) 240 print_exit("cannot read cert"); 241 if(!SSL_CTX_use_PrivateKey_file(ctx, key, SSL_FILETYPE_PEM)) 242 print_exit("cannot read key"); 243 if(!SSL_CTX_check_private_key(ctx)) 244 print_exit("private key is not correct"); 245 #if HAVE_DECL_SSL_CTX_SET_ECDH_AUTO 246 if (!SSL_CTX_set_ecdh_auto(ctx,1)) 247 if(verb>=1) printf("failed to set_ecdh_auto, not enabling ECDHE\n"); 248 #elif defined(USE_ECDSA) 249 if(1) { 250 EC_KEY *ecdh = EC_KEY_new_by_curve_name (NID_X9_62_prime256v1); 251 if (!ecdh) { 252 if(verb>=1) printf("could not find p256, not enabling ECDHE\n"); 253 } else { 254 if (1 != SSL_CTX_set_tmp_ecdh (ctx, ecdh)) { 255 if(verb>=1) printf("Error in SSL_CTX_set_tmp_ecdh, not enabling ECDHE\n"); 256 } 257 EC_KEY_free(ecdh); 258 } 259 } 260 #endif 261 if(!SSL_CTX_load_verify_locations(ctx, cert, NULL)) 262 print_exit("cannot load cert verify locations"); 263 return ctx; 264 } 265 266 /** setup listening TCP */ 267 static int 268 setup_fd(char* addr, int port) 269 { 270 struct sockaddr_storage ad; 271 socklen_t len; 272 int fd; 273 int c = 1; 274 int fam = parse_ip_addr(addr, port, &ad, &len); 275 fd = socket(fam, SOCK_STREAM, 0); 276 if(fd == -1) { 277 log_errno("socket"); 278 return -1; 279 } 280 if(setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, 281 (void*)&c, (socklen_t) sizeof(int)) < 0) { 282 log_errno("setsockopt(SOL_SOCKET, SO_REUSEADDR)"); 283 } 284 if(bind(fd, (struct sockaddr*)&ad, len) == -1) { 285 log_errno("bind"); 286 fd_close(fd); 287 return -1; 288 } 289 if(listen(fd, 5) == -1) { 290 log_errno("listen"); 291 fd_close(fd); 292 return -1; 293 } 294 return fd; 295 } 296 297 /** setup SSL connection to the client */ 298 static SSL* 299 setup_ssl(int s, SSL_CTX* ctx) 300 { 301 SSL* ssl = SSL_new(ctx); 302 if(!ssl) return NULL; 303 SSL_set_accept_state(ssl); 304 (void)SSL_set_mode(ssl, SSL_MODE_AUTO_RETRY); 305 if(!SSL_set_fd(ssl, s)) { 306 SSL_free(ssl); 307 return NULL; 308 } 309 return ssl; 310 } 311 312 /** check a file name for safety */ 313 static int 314 file_name_is_safe(char* s) 315 { 316 size_t l = strlen(s); 317 if(s[0] != '/') 318 return 0; /* must start with / */ 319 if(strstr(s, "/../")) 320 return 0; /* no updirs in URL */ 321 if(l>=3 && s[l-1]=='.' && s[l-2]=='.' && s[l-3]=='/') 322 return 0; /* ends with /.. */ 323 return 1; 324 } 325 326 /** adjust host and filename */ 327 static void 328 adjust_host_file(char* host, char* file) 329 { 330 size_t i, len; 331 /* remove a port number if present */ 332 if(strrchr(host, ':')) 333 *strrchr(host, ':') = 0; 334 /* lowercase */ 335 len = strlen(host); 336 for(i=0; i<len; i++) 337 host[i] = tolower((unsigned char)host[i]); 338 len = strlen(file); 339 for(i=0; i<len; i++) 340 file[i] = tolower((unsigned char)file[i]); 341 } 342 343 /** check a host name for safety */ 344 static int 345 host_name_is_safe(char* s) 346 { 347 if(strchr(s, '/')) 348 return 0; 349 if(strcmp(s, "..") == 0) 350 return 0; 351 if(strcmp(s, ".") == 0) 352 return 0; 353 return 1; 354 } 355 356 /** provide file in whole transfer */ 357 static void 358 provide_file_10(SSL* ssl, char* fname) 359 { 360 char* buf, *at; 361 size_t len, avail, header_reserve=1024; 362 FILE* in = fopen(fname, 363 #ifndef USE_WINSOCK 364 "r" 365 #else 366 "rb" 367 #endif 368 ); 369 size_t r; 370 const char* rcode = "200 OK"; 371 if(!in) { 372 char hdr[1024]; 373 rcode = "404 File not found"; 374 snprintf(hdr, sizeof(hdr), "HTTP/1.1 %s\r\n\r\n", rcode); 375 r = strlen(hdr); 376 if(SSL_write(ssl, hdr, (int)r) <= 0) { 377 /* write failure */ 378 } 379 return; 380 } 381 fseek(in, 0, SEEK_END); 382 len = (size_t)ftell(in); 383 fseek(in, 0, SEEK_SET); 384 /* plus some space for the header */ 385 buf = (char*)malloc(len+header_reserve); 386 if(!buf) { 387 fclose(in); 388 return; 389 } 390 avail = len+header_reserve; 391 at = buf; 392 snprintf(at, avail, "HTTP/1.1 %s\r\n", rcode); 393 r = strlen(at); 394 at += r; 395 avail -= r; 396 snprintf(at, avail, "Server: petal/%s\r\n", PACKAGE_VERSION); 397 r = strlen(at); 398 at += r; 399 avail -= r; 400 snprintf(at, avail, "Content-Length: %u\r\n", (unsigned)len); 401 r = strlen(at); 402 at += r; 403 avail -= r; 404 snprintf(at, avail, "\r\n"); 405 r = strlen(at); 406 at += r; 407 avail -= r; 408 if(avail < len) { /* robust */ 409 free(buf); 410 fclose(in); 411 return; 412 } 413 if(fread(at, 1, len, in) != len) { 414 free(buf); 415 fclose(in); 416 return; 417 } 418 fclose(in); 419 at += len; 420 avail -= len; 421 if(SSL_write(ssl, buf, at-buf) <= 0) { 422 /* write failure */ 423 } 424 free(buf); 425 } 426 427 /** provide file over SSL, chunked encoding */ 428 static void 429 provide_file_chunked(SSL* ssl, char* fname) 430 { 431 char buf[16384]; 432 char* tmpbuf = NULL; 433 char* at = buf; 434 size_t avail = sizeof(buf); 435 size_t r; 436 FILE* in = fopen(fname, 437 #ifndef USE_WINSOCK 438 "r" 439 #else 440 "rb" 441 #endif 442 ); 443 const char* rcode = "200 OK"; 444 if(!in) { 445 rcode = "404 File not found"; 446 } 447 448 /* print headers */ 449 snprintf(at, avail, "HTTP/1.1 %s\r\n", rcode); 450 r = strlen(at); 451 at += r; 452 avail -= r; 453 snprintf(at, avail, "Server: petal/%s\r\n", PACKAGE_VERSION); 454 r = strlen(at); 455 at += r; 456 avail -= r; 457 snprintf(at, avail, "Transfer-Encoding: chunked\r\n"); 458 r = strlen(at); 459 at += r; 460 avail -= r; 461 snprintf(at, avail, "Connection: close\r\n"); 462 r = strlen(at); 463 at += r; 464 avail -= r; 465 snprintf(at, avail, "\r\n"); 466 r = strlen(at); 467 at += r; 468 avail -= r; 469 if(avail < 16) { /* robust */ 470 if(in) fclose(in); 471 return; 472 } 473 474 do { 475 size_t red; 476 free(tmpbuf); 477 tmpbuf = malloc(avail-16); 478 if(!tmpbuf) 479 break; 480 /* read chunk; space-16 for xxxxCRLF..CRLF0CRLFCRLF (3 spare)*/ 481 red = in?fread(tmpbuf, 1, avail-16, in):0; 482 /* prepare chunk */ 483 snprintf(at, avail, "%x\r\n", (unsigned)red); 484 r = strlen(at); 485 if(verb >= 3) 486 {printf("chunk len %x\n", (unsigned)red); fflush(stdout);} 487 at += r; 488 avail -= r; 489 if(red != 0) { 490 if(red > avail) break; /* robust */ 491 memmove(at, tmpbuf, red); 492 at += red; 493 avail -= red; 494 snprintf(at, avail, "\r\n"); 495 r = strlen(at); 496 at += r; 497 avail -= r; 498 } 499 if(in && feof(in) && red != 0) { 500 snprintf(at, avail, "0\r\n"); 501 r = strlen(at); 502 at += r; 503 avail -= r; 504 } 505 if(!in || feof(in)) { 506 snprintf(at, avail, "\r\n"); 507 r = strlen(at); 508 at += r; 509 avail -= r; 510 } 511 /* send chunk */ 512 if(SSL_write(ssl, buf, at-buf) <= 0) { 513 /* SSL error */ 514 break; 515 } 516 517 /* setup for next chunk */ 518 at = buf; 519 avail = sizeof(buf); 520 } while(in && !feof(in) && !ferror(in)); 521 522 free(tmpbuf); 523 if(in) fclose(in); 524 } 525 526 /** provide service to the ssl descriptor */ 527 static void 528 service_ssl(SSL* ssl, struct sockaddr_storage* from, socklen_t falen) 529 { 530 char file[1024]; 531 char host[1024]; 532 char combined[2048]; 533 int vs = 11; 534 if(!read_http_headers(ssl, file, sizeof(file), host, sizeof(host), 535 &vs)) 536 return; 537 adjust_host_file(host, file); 538 if(host[0] == 0 || !host_name_is_safe(host)) 539 (void)strlcpy(host, "default", sizeof(host)); 540 if(!file_name_is_safe(file)) { 541 return; 542 } 543 snprintf(combined, sizeof(combined), "%s%s", host, file); 544 if(verb) { 545 char out[100]; 546 void* a = &((struct sockaddr_in*)from)->sin_addr; 547 if(falen != (socklen_t)sizeof(struct sockaddr_in)) 548 a = &((struct sockaddr_in6*)from)->sin6_addr; 549 out[0]=0; 550 (void)inet_ntop((int)((struct sockaddr_in*)from)->sin_family, 551 a, out, (socklen_t)sizeof(out)); 552 printf("%s requests %s\n", out, combined); 553 fflush(stdout); 554 } 555 if(vs == 10) 556 provide_file_10(ssl, combined); 557 else provide_file_chunked(ssl, combined); 558 } 559 560 /** provide ssl service */ 561 static void 562 do_service(char* addr, int port, char* key, char* cert) 563 { 564 SSL_CTX* sslctx = setup_ctx(key, cert); 565 int fd = setup_fd(addr, port); 566 int go = 1; 567 if(fd == -1) print_exit("could not setup sockets"); 568 if(verb) {printf("petal start\n"); fflush(stdout);} 569 while(go) { 570 struct sockaddr_storage from; 571 socklen_t flen = (socklen_t)sizeof(from); 572 int s = accept(fd, (struct sockaddr*)&from, &flen); 573 if(verb) fflush(stdout); 574 if(s != -1) { 575 SSL* ssl = setup_ssl(s, sslctx); 576 if(verb) fflush(stdout); 577 if(ssl) { 578 service_ssl(ssl, &from, flen); 579 if(verb) fflush(stdout); 580 SSL_shutdown(ssl); 581 SSL_free(ssl); 582 } 583 fd_close(s); 584 } else if (verb >=2) log_errno("accept"); 585 if(verb) fflush(stdout); 586 } 587 /* if we get a kill signal, the process dies and the OS reaps us */ 588 if(verb) printf("petal end\n"); 589 fd_close(fd); 590 SSL_CTX_free(sslctx); 591 } 592 593 /** getopt global, in case header files fail to declare it. */ 594 extern int optind; 595 /** getopt global, in case header files fail to declare it. */ 596 extern char* optarg; 597 598 /** Main routine for petal */ 599 int main(int argc, char* argv[]) 600 { 601 int c; 602 int port = 443; 603 char* addr = "127.0.0.1", *key = "petal.key", *cert = "petal.pem"; 604 #ifdef USE_WINSOCK 605 WSADATA wsa_data; 606 if((c=WSAStartup(MAKEWORD(2,2), &wsa_data)) != 0) 607 { printf("WSAStartup failed\n"); exit(1); } 608 atexit((void (*)(void))WSACleanup); 609 #endif 610 611 /* parse the options */ 612 while( (c=getopt(argc, argv, "a:c:k:hp:v")) != -1) { 613 switch(c) { 614 case 'a': 615 addr = optarg; 616 break; 617 case 'c': 618 cert = optarg; 619 break; 620 case 'k': 621 key = optarg; 622 break; 623 case 'p': 624 port = atoi(optarg); 625 break; 626 case 'v': 627 verb++; 628 break; 629 case '?': 630 case 'h': 631 default: 632 usage(); 633 } 634 } 635 argc -= optind; 636 argv += optind; 637 if(argc != 0) 638 usage(); 639 640 #ifdef SIGPIPE 641 (void)signal(SIGPIPE, SIG_IGN); 642 #endif 643 #ifdef HAVE_ERR_LOAD_CRYPTO_STRINGS 644 ERR_load_crypto_strings(); 645 #endif 646 #if OPENSSL_VERSION_NUMBER < 0x10100000 || !defined(HAVE_OPENSSL_INIT_SSL) 647 ERR_load_SSL_strings(); 648 #endif 649 #if OPENSSL_VERSION_NUMBER < 0x10100000 || !defined(HAVE_OPENSSL_INIT_CRYPTO) 650 OpenSSL_add_all_algorithms(); 651 #else 652 OPENSSL_init_crypto(OPENSSL_INIT_ADD_ALL_CIPHERS 653 | OPENSSL_INIT_ADD_ALL_DIGESTS 654 | OPENSSL_INIT_LOAD_CRYPTO_STRINGS, NULL); 655 #endif 656 #if OPENSSL_VERSION_NUMBER < 0x10100000 || !defined(HAVE_OPENSSL_INIT_SSL) 657 (void)SSL_library_init(); 658 #else 659 (void)OPENSSL_init_ssl(OPENSSL_INIT_LOAD_SSL_STRINGS, NULL); 660 #endif 661 662 do_service(addr, port, key, cert); 663 664 #ifdef HAVE_CRYPTO_CLEANUP_ALL_EX_DATA 665 CRYPTO_cleanup_all_ex_data(); 666 #endif 667 #ifdef HAVE_ERR_FREE_STRINGS 668 ERR_free_strings(); 669 #endif 670 return 0; 671 } 672