1 /* 2 * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 3. The name of the author may not be used to endorse or promote products 13 * derived from this software without specific prior written permission. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 #ifndef EVENT2_UTIL_H_INCLUDED_ 27 #define EVENT2_UTIL_H_INCLUDED_ 28 29 /** @file event2/util.h 30 31 Common convenience functions for cross-platform portability and 32 related socket manipulations. 33 34 */ 35 #include <event2/visibility.h> 36 37 #ifdef __cplusplus 38 extern "C" { 39 #endif 40 41 #include <event2/event-config.h> 42 #ifdef EVENT__HAVE_SYS_TIME_H 43 #include <sys/time.h> 44 #endif 45 #ifdef EVENT__HAVE_STDINT_H 46 #include <stdint.h> 47 #elif defined(EVENT__HAVE_INTTYPES_H) 48 #include <inttypes.h> 49 #endif 50 #ifdef EVENT__HAVE_SYS_TYPES_H 51 #include <sys/types.h> 52 #endif 53 #ifdef EVENT__HAVE_STDDEF_H 54 #include <stddef.h> 55 #endif 56 #ifdef _MSC_VER 57 #include <BaseTsd.h> 58 #endif 59 #include <stdarg.h> 60 #ifdef EVENT__HAVE_NETDB_H 61 #if !defined(_GNU_SOURCE) 62 #define _GNU_SOURCE 63 #endif 64 #include <netdb.h> 65 #endif 66 67 #ifdef _WIN32 68 #include <winsock2.h> 69 #ifdef EVENT__HAVE_GETADDRINFO 70 /* for EAI_* definitions. */ 71 #include <ws2tcpip.h> 72 #endif 73 #else 74 #include <sys/socket.h> 75 #endif 76 77 /* Some openbsd autoconf versions get the name of this macro wrong. */ 78 #if defined(EVENT__SIZEOF_VOID__) && !defined(EVENT__SIZEOF_VOID_P) 79 #define EVENT__SIZEOF_VOID_P EVENT__SIZEOF_VOID__ 80 #endif 81 82 /** 83 * @name Standard integer types. 84 * 85 * Integer type definitions for types that are supposed to be defined in the 86 * C99-specified stdint.h. Shamefully, some platforms do not include 87 * stdint.h, so we need to replace it. (If you are on a platform like this, 88 * your C headers are now over 10 years out of date. You should bug them to 89 * do something about this.) 90 * 91 * We define: 92 * 93 * <dl> 94 * <dt>ev_uint64_t, ev_uint32_t, ev_uint16_t, ev_uint8_t</dt> 95 * <dd>unsigned integer types of exactly 64, 32, 16, and 8 bits 96 * respectively.</dd> 97 * <dt>ev_int64_t, ev_int32_t, ev_int16_t, ev_int8_t</dt> 98 * <dd>signed integer types of exactly 64, 32, 16, and 8 bits 99 * respectively.</dd> 100 * <dt>ev_uintptr_t, ev_intptr_t</dt> 101 * <dd>unsigned/signed integers large enough 102 * to hold a pointer without loss of bits.</dd> 103 * <dt>ev_ssize_t</dt> 104 * <dd>A signed type of the same size as size_t</dd> 105 * <dt>ev_off_t</dt> 106 * <dd>A signed type typically used to represent offsets within a 107 * (potentially large) file</dd> 108 * 109 * @{ 110 */ 111 #ifdef EVENT__HAVE_UINT64_T 112 #define ev_uint64_t uint64_t 113 #define ev_int64_t int64_t 114 #elif defined(_WIN32) 115 #define ev_uint64_t unsigned __int64 116 #define ev_int64_t signed __int64 117 #elif EVENT__SIZEOF_LONG_LONG == 8 118 #define ev_uint64_t unsigned long long 119 #define ev_int64_t long long 120 #elif EVENT__SIZEOF_LONG == 8 121 #define ev_uint64_t unsigned long 122 #define ev_int64_t long 123 #elif defined(EVENT_IN_DOXYGEN_) 124 #define ev_uint64_t ... 125 #define ev_int64_t ... 126 #else 127 #error "No way to define ev_uint64_t" 128 #endif 129 130 #ifdef EVENT__HAVE_UINT32_T 131 #define ev_uint32_t uint32_t 132 #define ev_int32_t int32_t 133 #elif defined(_WIN32) 134 #define ev_uint32_t unsigned int 135 #define ev_int32_t signed int 136 #elif EVENT__SIZEOF_LONG == 4 137 #define ev_uint32_t unsigned long 138 #define ev_int32_t signed long 139 #elif EVENT__SIZEOF_INT == 4 140 #define ev_uint32_t unsigned int 141 #define ev_int32_t signed int 142 #elif defined(EVENT_IN_DOXYGEN_) 143 #define ev_uint32_t ... 144 #define ev_int32_t ... 145 #else 146 #error "No way to define ev_uint32_t" 147 #endif 148 149 #ifdef EVENT__HAVE_UINT16_T 150 #define ev_uint16_t uint16_t 151 #define ev_int16_t int16_t 152 #elif defined(_WIN32) 153 #define ev_uint16_t unsigned short 154 #define ev_int16_t signed short 155 #elif EVENT__SIZEOF_INT == 2 156 #define ev_uint16_t unsigned int 157 #define ev_int16_t signed int 158 #elif EVENT__SIZEOF_SHORT == 2 159 #define ev_uint16_t unsigned short 160 #define ev_int16_t signed short 161 #elif defined(EVENT_IN_DOXYGEN_) 162 #define ev_uint16_t ... 163 #define ev_int16_t ... 164 #else 165 #error "No way to define ev_uint16_t" 166 #endif 167 168 #ifdef EVENT__HAVE_UINT8_T 169 #define ev_uint8_t uint8_t 170 #define ev_int8_t int8_t 171 #elif defined(EVENT_IN_DOXYGEN_) 172 #define ev_uint8_t ... 173 #define ev_int8_t ... 174 #else 175 #define ev_uint8_t unsigned char 176 #define ev_int8_t signed char 177 #endif 178 179 #ifdef EVENT__HAVE_UINTPTR_T 180 #define ev_uintptr_t uintptr_t 181 #define ev_intptr_t intptr_t 182 #elif EVENT__SIZEOF_VOID_P <= 4 183 #define ev_uintptr_t ev_uint32_t 184 #define ev_intptr_t ev_int32_t 185 #elif EVENT__SIZEOF_VOID_P <= 8 186 #define ev_uintptr_t ev_uint64_t 187 #define ev_intptr_t ev_int64_t 188 #elif defined(EVENT_IN_DOXYGEN_) 189 #define ev_uintptr_t ... 190 #define ev_intptr_t ... 191 #else 192 #error "No way to define ev_uintptr_t" 193 #endif 194 195 #ifdef EVENT__ssize_t 196 #define ev_ssize_t EVENT__ssize_t 197 #else 198 #define ev_ssize_t ssize_t 199 #endif 200 201 /* Note that we define ev_off_t based on the compile-time size of off_t that 202 * we used to build Libevent, and not based on the current size of off_t. 203 * (For example, we don't define ev_off_t to off_t.). We do this because 204 * some systems let you build your software with different off_t sizes 205 * at runtime, and so putting in any dependency on off_t would risk API 206 * mismatch. 207 */ 208 #ifdef _WIN32 209 #define ev_off_t ev_int64_t 210 #elif EVENT__SIZEOF_OFF_T == 8 211 #define ev_off_t ev_int64_t 212 #elif EVENT__SIZEOF_OFF_T == 4 213 #define ev_off_t ev_int32_t 214 #elif defined(EVENT_IN_DOXYGEN_) 215 #define ev_off_t ... 216 #else 217 #define ev_off_t off_t 218 #endif 219 /**@}*/ 220 221 /* Limits for integer types. 222 223 We're making two assumptions here: 224 - The compiler does constant folding properly. 225 - The platform does signed arithmetic in two's complement. 226 */ 227 228 /** 229 @name Limits for integer types 230 231 These macros hold the largest or smallest values possible for the 232 ev_[u]int*_t types. 233 234 @{ 235 */ 236 #define EV_UINT64_MAX ((((ev_uint64_t)0xffffffffUL) << 32) | 0xffffffffUL) 237 #define EV_INT64_MAX ((((ev_int64_t) 0x7fffffffL) << 32) | 0xffffffffL) 238 #define EV_INT64_MIN ((-EV_INT64_MAX) - 1) 239 #define EV_UINT32_MAX ((ev_uint32_t)0xffffffffUL) 240 #define EV_INT32_MAX ((ev_int32_t) 0x7fffffffL) 241 #define EV_INT32_MIN ((-EV_INT32_MAX) - 1) 242 #define EV_UINT16_MAX ((ev_uint16_t)0xffffUL) 243 #define EV_INT16_MAX ((ev_int16_t) 0x7fffL) 244 #define EV_INT16_MIN ((-EV_INT16_MAX) - 1) 245 #define EV_UINT8_MAX 255 246 #define EV_INT8_MAX 127 247 #define EV_INT8_MIN ((-EV_INT8_MAX) - 1) 248 /** @} */ 249 250 /** 251 @name Limits for SIZE_T and SSIZE_T 252 253 @{ 254 */ 255 #if EVENT__SIZEOF_SIZE_T == 8 256 #define EV_SIZE_MAX EV_UINT64_MAX 257 #define EV_SSIZE_MAX EV_INT64_MAX 258 #elif EVENT__SIZEOF_SIZE_T == 4 259 #define EV_SIZE_MAX EV_UINT32_MAX 260 #define EV_SSIZE_MAX EV_INT32_MAX 261 #elif defined(EVENT_IN_DOXYGEN_) 262 #define EV_SIZE_MAX ... 263 #define EV_SSIZE_MAX ... 264 #else 265 #error "No way to define SIZE_MAX" 266 #endif 267 268 #define EV_SSIZE_MIN ((-EV_SSIZE_MAX) - 1) 269 /**@}*/ 270 271 #ifdef _WIN32 272 #define ev_socklen_t int 273 #elif defined(EVENT__socklen_t) 274 #define ev_socklen_t EVENT__socklen_t 275 #else 276 #define ev_socklen_t socklen_t 277 #endif 278 279 #ifdef EVENT__HAVE_STRUCT_SOCKADDR_STORAGE___SS_FAMILY 280 #if !defined(EVENT__HAVE_STRUCT_SOCKADDR_STORAGE_SS_FAMILY) \ 281 && !defined(ss_family) 282 #define ss_family __ss_family 283 #endif 284 #endif 285 286 /** 287 * A type wide enough to hold the output of "socket()" or "accept()". On 288 * Windows, this is an intptr_t; elsewhere, it is an int. */ 289 #ifdef _WIN32 290 #define evutil_socket_t intptr_t 291 #else 292 #define evutil_socket_t int 293 #endif 294 295 /** Create two new sockets that are connected to each other. 296 297 On Unix, this simply calls socketpair(). On Windows, it uses the 298 loopback network interface on 127.0.0.1, and only 299 AF_INET,SOCK_STREAM are supported. 300 301 (This may fail on some Windows hosts where firewall software has cleverly 302 decided to keep 127.0.0.1 from talking to itself.) 303 304 Parameters and return values are as for socketpair() 305 */ 306 EVENT2_EXPORT_SYMBOL 307 int evutil_socketpair(int d, int type, int protocol, evutil_socket_t sv[2]); 308 /** Do platform-specific operations as needed to make a socket nonblocking. 309 310 @param sock The socket to make nonblocking 311 @return 0 on success, -1 on failure 312 */ 313 EVENT2_EXPORT_SYMBOL 314 int evutil_make_socket_nonblocking(evutil_socket_t sock); 315 316 /** Do platform-specific operations to make a listener socket reusable. 317 318 Specifically, we want to make sure that another program will be able 319 to bind this address right after we've closed the listener. 320 321 This differs from Windows's interpretation of "reusable", which 322 allows multiple listeners to bind the same address at the same time. 323 324 @param sock The socket to make reusable 325 @return 0 on success, -1 on failure 326 */ 327 EVENT2_EXPORT_SYMBOL 328 int evutil_make_listen_socket_reuseable(evutil_socket_t sock); 329 330 /** Do platform-specific operations as needed to close a socket upon a 331 successful execution of one of the exec*() functions. 332 333 @param sock The socket to be closed 334 @return 0 on success, -1 on failure 335 */ 336 EVENT2_EXPORT_SYMBOL 337 int evutil_make_socket_closeonexec(evutil_socket_t sock); 338 339 /** Do the platform-specific call needed to close a socket returned from 340 socket() or accept(). 341 342 @param sock The socket to be closed 343 @return 0 on success, -1 on failure 344 */ 345 EVENT2_EXPORT_SYMBOL 346 int evutil_closesocket(evutil_socket_t sock); 347 #define EVUTIL_CLOSESOCKET(s) evutil_closesocket(s) 348 349 /** Do platform-specific operations, if possible, to make a tcp listener 350 * socket defer accept()s until there is data to read. 351 * 352 * Not all platforms support this. You don't want to do this for every 353 * listener socket: only the ones that implement a protocol where the 354 * client transmits before the server needs to respond. 355 * 356 * @param sock The listening socket to to make deferred 357 * @return 0 on success (whether the operation is supported or not), 358 * -1 on failure 359 */ 360 EVENT2_EXPORT_SYMBOL 361 int evutil_make_tcp_listen_socket_deferred(evutil_socket_t sock); 362 363 #ifdef _WIN32 364 /** Return the most recent socket error. Not idempotent on all platforms. */ 365 #define EVUTIL_SOCKET_ERROR() WSAGetLastError() 366 /** Replace the most recent socket error with errcode */ 367 #define EVUTIL_SET_SOCKET_ERROR(errcode) \ 368 do { WSASetLastError(errcode); } while (0) 369 /** Return the most recent socket error to occur on sock. */ 370 EVENT2_EXPORT_SYMBOL 371 int evutil_socket_geterror(evutil_socket_t sock); 372 /** Convert a socket error to a string. */ 373 EVENT2_EXPORT_SYMBOL 374 const char *evutil_socket_error_to_string(int errcode); 375 #elif defined(EVENT_IN_DOXYGEN_) 376 /** 377 @name Socket error functions 378 379 These functions are needed for making programs compatible between 380 Windows and Unix-like platforms. 381 382 You see, Winsock handles socket errors differently from the rest of 383 the world. Elsewhere, a socket error is like any other error and is 384 stored in errno. But winsock functions require you to retrieve the 385 error with a special function, and don't let you use strerror for 386 the error codes. And handling EWOULDBLOCK is ... different. 387 388 @{ 389 */ 390 /** Return the most recent socket error. Not idempotent on all platforms. */ 391 #define EVUTIL_SOCKET_ERROR() ... 392 /** Replace the most recent socket error with errcode */ 393 #define EVUTIL_SET_SOCKET_ERROR(errcode) ... 394 /** Return the most recent socket error to occur on sock. */ 395 #define evutil_socket_geterror(sock) ... 396 /** Convert a socket error to a string. */ 397 #define evutil_socket_error_to_string(errcode) ... 398 /**@}*/ 399 #else 400 #define EVUTIL_SOCKET_ERROR() (errno) 401 #define EVUTIL_SET_SOCKET_ERROR(errcode) \ 402 do { errno = (errcode); } while (0) 403 #define evutil_socket_geterror(sock) (errno) 404 #define evutil_socket_error_to_string(errcode) (strerror(errcode)) 405 #endif 406 407 408 /** 409 * @name Manipulation macros for struct timeval. 410 * 411 * We define replacements 412 * for timeradd, timersub, timerclear, timercmp, and timerisset. 413 * 414 * @{ 415 */ 416 #ifdef EVENT__HAVE_TIMERADD 417 #define evutil_timeradd(tvp, uvp, vvp) timeradd((tvp), (uvp), (vvp)) 418 #define evutil_timersub(tvp, uvp, vvp) timersub((tvp), (uvp), (vvp)) 419 #else 420 #define evutil_timeradd(tvp, uvp, vvp) \ 421 do { \ 422 (vvp)->tv_sec = (tvp)->tv_sec + (uvp)->tv_sec; \ 423 (vvp)->tv_usec = (tvp)->tv_usec + (uvp)->tv_usec; \ 424 if ((vvp)->tv_usec >= 1000000) { \ 425 (vvp)->tv_sec++; \ 426 (vvp)->tv_usec -= 1000000; \ 427 } \ 428 } while (0) 429 #define evutil_timersub(tvp, uvp, vvp) \ 430 do { \ 431 (vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec; \ 432 (vvp)->tv_usec = (tvp)->tv_usec - (uvp)->tv_usec; \ 433 if ((vvp)->tv_usec < 0) { \ 434 (vvp)->tv_sec--; \ 435 (vvp)->tv_usec += 1000000; \ 436 } \ 437 } while (0) 438 #endif /* !EVENT__HAVE_TIMERADD */ 439 440 #ifdef EVENT__HAVE_TIMERCLEAR 441 #define evutil_timerclear(tvp) timerclear(tvp) 442 #else 443 #define evutil_timerclear(tvp) (tvp)->tv_sec = (tvp)->tv_usec = 0 444 #endif 445 /**@}*/ 446 447 /** Return true iff the tvp is related to uvp according to the relational 448 * operator cmp. Recognized values for cmp are ==, <=, <, >=, and >. */ 449 #define evutil_timercmp(tvp, uvp, cmp) \ 450 (((tvp)->tv_sec == (uvp)->tv_sec) ? \ 451 ((tvp)->tv_usec cmp (uvp)->tv_usec) : \ 452 ((tvp)->tv_sec cmp (uvp)->tv_sec)) 453 454 #ifdef EVENT__HAVE_TIMERISSET 455 #define evutil_timerisset(tvp) timerisset(tvp) 456 #else 457 #define evutil_timerisset(tvp) ((tvp)->tv_sec || (tvp)->tv_usec) 458 #endif 459 460 /** Replacement for offsetof on platforms that don't define it. */ 461 #ifdef offsetof 462 #define evutil_offsetof(type, field) offsetof(type, field) 463 #else 464 #define evutil_offsetof(type, field) ((off_t)(&((type *)0)->field)) 465 #endif 466 467 /* big-int related functions */ 468 /** Parse a 64-bit value from a string. Arguments are as for strtol. */ 469 EVENT2_EXPORT_SYMBOL 470 ev_int64_t evutil_strtoll(const char *s, char **endptr, int base); 471 472 /** Replacement for gettimeofday on platforms that lack it. */ 473 #ifdef EVENT__HAVE_GETTIMEOFDAY 474 #define evutil_gettimeofday(tv, tz) gettimeofday((tv), (tz)) 475 #else 476 struct timezone; 477 EVENT2_EXPORT_SYMBOL 478 int evutil_gettimeofday(struct timeval *tv, struct timezone *tz); 479 #endif 480 481 /** Replacement for snprintf to get consistent behavior on platforms for 482 which the return value of snprintf does not conform to C99. 483 */ 484 EVENT2_EXPORT_SYMBOL 485 int evutil_snprintf(char *buf, size_t buflen, const char *format, ...) 486 #ifdef __GNUC__ 487 __attribute__((format(printf, 3, 4))) 488 #endif 489 ; 490 /** Replacement for vsnprintf to get consistent behavior on platforms for 491 which the return value of snprintf does not conform to C99. 492 */ 493 EVENT2_EXPORT_SYMBOL 494 int evutil_vsnprintf(char *buf, size_t buflen, const char *format, va_list ap) 495 #ifdef __GNUC__ 496 __attribute__((format(printf, 3, 0))) 497 #endif 498 ; 499 500 /** Replacement for inet_ntop for platforms which lack it. */ 501 EVENT2_EXPORT_SYMBOL 502 const char *evutil_inet_ntop(int af, const void *src, char *dst, size_t len); 503 /** Replacement for inet_pton for platforms which lack it. */ 504 EVENT2_EXPORT_SYMBOL 505 int evutil_inet_pton(int af, const char *src, void *dst); 506 struct sockaddr; 507 508 /** Parse an IPv4 or IPv6 address, with optional port, from a string. 509 510 Recognized formats are: 511 - [IPv6Address]:port 512 - [IPv6Address] 513 - IPv6Address 514 - IPv4Address:port 515 - IPv4Address 516 517 If no port is specified, the port in the output is set to 0. 518 519 @param str The string to parse. 520 @param out A struct sockaddr to hold the result. This should probably be 521 a struct sockaddr_storage. 522 @param outlen A pointer to the number of bytes that that 'out' can safely 523 hold. Set to the number of bytes used in 'out' on success. 524 @return -1 if the address is not well-formed, if the port is out of range, 525 or if out is not large enough to hold the result. Otherwise returns 526 0 on success. 527 */ 528 EVENT2_EXPORT_SYMBOL 529 int evutil_parse_sockaddr_port(const char *str, struct sockaddr *out, int *outlen); 530 531 /** Compare two sockaddrs; return 0 if they are equal, or less than 0 if sa1 532 * preceeds sa2, or greater than 0 if sa1 follows sa2. If include_port is 533 * true, consider the port as well as the address. Only implemented for 534 * AF_INET and AF_INET6 addresses. The ordering is not guaranteed to remain 535 * the same between Libevent versions. */ 536 EVENT2_EXPORT_SYMBOL 537 int evutil_sockaddr_cmp(const struct sockaddr *sa1, const struct sockaddr *sa2, 538 int include_port); 539 540 /** As strcasecmp, but always compares the characters in locale-independent 541 ASCII. That's useful if you're handling data in ASCII-based protocols. 542 */ 543 EVENT2_EXPORT_SYMBOL 544 int evutil_ascii_strcasecmp(const char *str1, const char *str2); 545 /** As strncasecmp, but always compares the characters in locale-independent 546 ASCII. That's useful if you're handling data in ASCII-based protocols. 547 */ 548 EVENT2_EXPORT_SYMBOL 549 int evutil_ascii_strncasecmp(const char *str1, const char *str2, size_t n); 550 551 /* Here we define evutil_addrinfo to the native addrinfo type, or redefine it 552 * if this system has no getaddrinfo(). */ 553 #ifdef EVENT__HAVE_STRUCT_ADDRINFO 554 #define evutil_addrinfo addrinfo 555 #else 556 /** A definition of struct addrinfo for systems that lack it. 557 558 (This is just an alias for struct addrinfo if the system defines 559 struct addrinfo.) 560 */ 561 struct evutil_addrinfo { 562 int ai_flags; /* AI_PASSIVE, AI_CANONNAME, AI_NUMERICHOST */ 563 int ai_family; /* PF_xxx */ 564 int ai_socktype; /* SOCK_xxx */ 565 int ai_protocol; /* 0 or IPPROTO_xxx for IPv4 and IPv6 */ 566 size_t ai_addrlen; /* length of ai_addr */ 567 char *ai_canonname; /* canonical name for nodename */ 568 struct sockaddr *ai_addr; /* binary address */ 569 struct evutil_addrinfo *ai_next; /* next structure in linked list */ 570 }; 571 #endif 572 /** @name evutil_getaddrinfo() error codes 573 574 These values are possible error codes for evutil_getaddrinfo() and 575 related functions. 576 577 @{ 578 */ 579 #if defined(EAI_ADDRFAMILY) && defined(EVENT__HAVE_GETADDRINFO) 580 #define EVUTIL_EAI_ADDRFAMILY EAI_ADDRFAMILY 581 #else 582 #define EVUTIL_EAI_ADDRFAMILY -901 583 #endif 584 #if defined(EAI_AGAIN) && defined(EVENT__HAVE_GETADDRINFO) 585 #define EVUTIL_EAI_AGAIN EAI_AGAIN 586 #else 587 #define EVUTIL_EAI_AGAIN -902 588 #endif 589 #if defined(EAI_BADFLAGS) && defined(EVENT__HAVE_GETADDRINFO) 590 #define EVUTIL_EAI_BADFLAGS EAI_BADFLAGS 591 #else 592 #define EVUTIL_EAI_BADFLAGS -903 593 #endif 594 #if defined(EAI_FAIL) && defined(EVENT__HAVE_GETADDRINFO) 595 #define EVUTIL_EAI_FAIL EAI_FAIL 596 #else 597 #define EVUTIL_EAI_FAIL -904 598 #endif 599 #if defined(EAI_FAMILY) && defined(EVENT__HAVE_GETADDRINFO) 600 #define EVUTIL_EAI_FAMILY EAI_FAMILY 601 #else 602 #define EVUTIL_EAI_FAMILY -905 603 #endif 604 #if defined(EAI_MEMORY) && defined(EVENT__HAVE_GETADDRINFO) 605 #define EVUTIL_EAI_MEMORY EAI_MEMORY 606 #else 607 #define EVUTIL_EAI_MEMORY -906 608 #endif 609 /* This test is a bit complicated, since some MS SDKs decide to 610 * remove NODATA or redefine it to be the same as NONAME, in a 611 * fun interpretation of RFC 2553 and RFC 3493. */ 612 #if defined(EAI_NODATA) && defined(EVENT__HAVE_GETADDRINFO) && (!defined(EAI_NONAME) || EAI_NODATA != EAI_NONAME) 613 #define EVUTIL_EAI_NODATA EAI_NODATA 614 #else 615 #define EVUTIL_EAI_NODATA -907 616 #endif 617 #if defined(EAI_NONAME) && defined(EVENT__HAVE_GETADDRINFO) 618 #define EVUTIL_EAI_NONAME EAI_NONAME 619 #else 620 #define EVUTIL_EAI_NONAME -908 621 #endif 622 #if defined(EAI_SERVICE) && defined(EVENT__HAVE_GETADDRINFO) 623 #define EVUTIL_EAI_SERVICE EAI_SERVICE 624 #else 625 #define EVUTIL_EAI_SERVICE -909 626 #endif 627 #if defined(EAI_SOCKTYPE) && defined(EVENT__HAVE_GETADDRINFO) 628 #define EVUTIL_EAI_SOCKTYPE EAI_SOCKTYPE 629 #else 630 #define EVUTIL_EAI_SOCKTYPE -910 631 #endif 632 #if defined(EAI_SYSTEM) && defined(EVENT__HAVE_GETADDRINFO) 633 #define EVUTIL_EAI_SYSTEM EAI_SYSTEM 634 #else 635 #define EVUTIL_EAI_SYSTEM -911 636 #endif 637 638 #define EVUTIL_EAI_CANCEL -90001 639 640 #if defined(AI_PASSIVE) && defined(EVENT__HAVE_GETADDRINFO) 641 #define EVUTIL_AI_PASSIVE AI_PASSIVE 642 #else 643 #define EVUTIL_AI_PASSIVE 0x1000 644 #endif 645 #if defined(AI_CANONNAME) && defined(EVENT__HAVE_GETADDRINFO) 646 #define EVUTIL_AI_CANONNAME AI_CANONNAME 647 #else 648 #define EVUTIL_AI_CANONNAME 0x2000 649 #endif 650 #if defined(AI_NUMERICHOST) && defined(EVENT__HAVE_GETADDRINFO) 651 #define EVUTIL_AI_NUMERICHOST AI_NUMERICHOST 652 #else 653 #define EVUTIL_AI_NUMERICHOST 0x4000 654 #endif 655 #if defined(AI_NUMERICSERV) && defined(EVENT__HAVE_GETADDRINFO) 656 #define EVUTIL_AI_NUMERICSERV AI_NUMERICSERV 657 #else 658 #define EVUTIL_AI_NUMERICSERV 0x8000 659 #endif 660 #if defined(AI_V4MAPPED) && defined(EVENT__HAVE_GETADDRINFO) 661 #define EVUTIL_AI_V4MAPPED AI_V4MAPPED 662 #else 663 #define EVUTIL_AI_V4MAPPED 0x10000 664 #endif 665 #if defined(AI_ALL) && defined(EVENT__HAVE_GETADDRINFO) 666 #define EVUTIL_AI_ALL AI_ALL 667 #else 668 #define EVUTIL_AI_ALL 0x20000 669 #endif 670 #if defined(AI_ADDRCONFIG) && defined(EVENT__HAVE_GETADDRINFO) 671 #define EVUTIL_AI_ADDRCONFIG AI_ADDRCONFIG 672 #else 673 #define EVUTIL_AI_ADDRCONFIG 0x40000 674 #endif 675 /**@}*/ 676 677 struct evutil_addrinfo; 678 /** 679 * This function clones getaddrinfo for systems that don't have it. For full 680 * details, see RFC 3493, section 6.1. 681 * 682 * Limitations: 683 * - When the system has no getaddrinfo, we fall back to gethostbyname_r or 684 * gethostbyname, with their attendant issues. 685 * - The AI_V4MAPPED and AI_ALL flags are not currently implemented. 686 * 687 * For a nonblocking variant, see evdns_getaddrinfo. 688 */ 689 EVENT2_EXPORT_SYMBOL 690 int evutil_getaddrinfo(const char *nodename, const char *servname, 691 const struct evutil_addrinfo *hints_in, struct evutil_addrinfo **res); 692 693 /** Release storage allocated by evutil_getaddrinfo or evdns_getaddrinfo. */ 694 EVENT2_EXPORT_SYMBOL 695 void evutil_freeaddrinfo(struct evutil_addrinfo *ai); 696 697 EVENT2_EXPORT_SYMBOL 698 const char *evutil_gai_strerror(int err); 699 700 /** Generate n bytes of secure pseudorandom data, and store them in buf. 701 * 702 * Current versions of Libevent use an ARC4-based random number generator, 703 * seeded using the platform's entropy source (/dev/urandom on Unix-like 704 * systems; CryptGenRandom on Windows). This is not actually as secure as it 705 * should be: ARC4 is a pretty lousy cipher, and the current implementation 706 * provides only rudimentary prediction- and backtracking-resistance. Don't 707 * use this for serious cryptographic applications. 708 */ 709 EVENT2_EXPORT_SYMBOL 710 void evutil_secure_rng_get_bytes(void *buf, size_t n); 711 712 /** 713 * Seed the secure random number generator if needed, and return 0 on 714 * success or -1 on failure. 715 * 716 * It is okay to call this function more than once; it will still return 717 * 0 if the RNG has been successfully seeded and -1 if it can't be 718 * seeded. 719 * 720 * Ordinarily you don't need to call this function from your own code; 721 * Libevent will seed the RNG itself the first time it needs good random 722 * numbers. You only need to call it if (a) you want to double-check 723 * that one of the seeding methods did succeed, or (b) you plan to drop 724 * the capability to seed (by chrooting, or dropping capabilities, or 725 * whatever), and you want to make sure that seeding happens before your 726 * program loses the ability to do it. 727 */ 728 EVENT2_EXPORT_SYMBOL 729 int evutil_secure_rng_init(void); 730 731 /** 732 * Set a filename to use in place of /dev/urandom for seeding the secure 733 * PRNG. Return 0 on success, -1 on failure. 734 * 735 * Call this function BEFORE calling any other initialization or RNG 736 * functions. 737 * 738 * (This string will _NOT_ be copied internally. Do not free it while any 739 * user of the secure RNG might be running. Don't pass anything other than a 740 * real /dev/...random device file here, or you might lose security.) 741 * 742 * This API is unstable, and might change in a future libevent version. 743 */ 744 EVENT2_EXPORT_SYMBOL 745 int evutil_secure_rng_set_urandom_device_file(char *fname); 746 747 /** Seed the random number generator with extra random bytes. 748 749 You should almost never need to call this function; it should be 750 sufficient to invoke evutil_secure_rng_init(), or let Libevent take 751 care of calling evutil_secure_rng_init() on its own. 752 753 If you call this function as a _replacement_ for the regular 754 entropy sources, then you need to be sure that your input 755 contains a fairly large amount of strong entropy. Doing so is 756 notoriously hard: most people who try get it wrong. Watch out! 757 758 @param dat a buffer full of a strong source of random numbers 759 @param datlen the number of bytes to read from datlen 760 */ 761 EVENT2_EXPORT_SYMBOL 762 void evutil_secure_rng_add_bytes(const char *dat, size_t datlen); 763 764 #ifdef __cplusplus 765 } 766 #endif 767 768 #endif /* EVENT1_EVUTIL_H_INCLUDED_ */ 769