/* * Copyright (c) 2002 - 2003 * NetGroup, Politecnico di Torino (Italy) * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the Politecnico di Torino nor the names of its * contributors may be used to endorse or promote products derived from * this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */ #include /* * \file sockutils.c * * The goal of this file is to provide a common set of primitives for socket * manipulation. * * Although the socket interface defined in the RFC 2553 (and its updates) * is excellent, there are still differences between the behavior of those * routines on UN*X and Windows, and between UN*Xes. * * These calls provide an interface similar to the socket interface, but * that hides the differences between operating systems. It does not * attempt to significantly improve on the socket interface in other * ways. */ #include "ftmacros.h" #include #include /* for the errno variable */ #include /* for the stderr file */ #include /* for malloc() and free() */ #include /* for INT_MAX */ #include "pcap-int.h" #include "sockutils.h" #include "portability.h" #ifdef _WIN32 /* * Winsock initialization. * * Ask for Winsock 2.2. */ #define WINSOCK_MAJOR_VERSION 2 #define WINSOCK_MINOR_VERSION 2 static int sockcount = 0; /*!< Variable that allows calling the WSAStartup() only one time */ #endif /* Some minor differences between UNIX and Win32 */ #ifdef _WIN32 #define SHUT_WR SD_SEND /* The control code for shutdown() is different in Win32 */ #endif /* Size of the buffer that has to keep error messages */ #define SOCK_ERRBUF_SIZE 1024 /* Constants; used in order to keep strings here */ #define SOCKET_NO_NAME_AVAILABLE "No name available" #define SOCKET_NO_PORT_AVAILABLE "No port available" #define SOCKET_NAME_NULL_DAD "Null address (possibly DAD Phase)" /* * On UN*X, send() and recv() return ssize_t. * * On Windows, send() and recv() return an int. * * With MSVC, there *is* no ssize_t. * * With MinGW, there is an ssize_t type; it is either an int (32 bit) * or a long long (64 bit). * * So, on Windows, if we don't have ssize_t defined, define it as an * int, so we can use it, on all platforms, as the type of variables * that hold the return values from send() and recv(). */ #if defined(_WIN32) && !defined(_SSIZE_T_DEFINED) typedef int ssize_t; #endif /**************************************************** * * * Locally defined functions * * * ****************************************************/ static int sock_ismcastaddr(const struct sockaddr *saddr); /**************************************************** * * * Function bodies * * * ****************************************************/ #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION const uint8_t *fuzzBuffer; size_t fuzzSize; size_t fuzzPos; void sock_initfuzz(const uint8_t *Data, size_t Size) { fuzzPos = 0; fuzzSize = Size; fuzzBuffer = Data; } static int fuzz_recv(char *bufp, int remaining) { if (remaining > fuzzSize - fuzzPos) { remaining = fuzzSize - fuzzPos; } if (fuzzPos < fuzzSize) { memcpy(bufp, fuzzBuffer + fuzzPos, remaining); } fuzzPos += remaining; return remaining; } #endif int sock_geterrcode(void) { #ifdef _WIN32 return GetLastError(); #else return errno; #endif } /* * Format an error message given an errno value (UN*X) or a Winsock error * (Windows). */ void sock_vfmterrmsg(char *errbuf, size_t errbuflen, int errcode, const char *fmt, va_list ap) { if (errbuf == NULL) return; #ifdef _WIN32 pcapint_vfmt_errmsg_for_win32_err(errbuf, errbuflen, errcode, fmt, ap); #else pcapint_vfmt_errmsg_for_errno(errbuf, errbuflen, errcode, fmt, ap); #endif } void sock_fmterrmsg(char *errbuf, size_t errbuflen, int errcode, const char *fmt, ...) { va_list ap; va_start(ap, fmt); sock_vfmterrmsg(errbuf, errbuflen, errcode, fmt, ap); va_end(ap); } /* * Format an error message for the last socket error. */ void sock_geterrmsg(char *errbuf, size_t errbuflen, const char *fmt, ...) { va_list ap; va_start(ap, fmt); sock_vfmterrmsg(errbuf, errbuflen, sock_geterrcode(), fmt, ap); va_end(ap); } /* * Types of error. * * These are sorted by how likely they are to be the "underlying" problem, * so that lower-rated errors for a given address in a given family * should not overwrite higher-rated errors for another address in that * family, and higher-rated errors should overwrite lower-rated errors. */ typedef enum { SOCK_CONNERR, /* connection error */ SOCK_HOSTERR, /* host error */ SOCK_NETERR, /* network error */ SOCK_AFNOTSUPERR, /* address family not supported */ SOCK_UNKNOWNERR, /* unknown error */ SOCK_NOERR /* no error */ } sock_errtype; static sock_errtype sock_geterrtype(int errcode) { switch (errcode) { #ifdef _WIN32 case WSAECONNRESET: case WSAECONNABORTED: case WSAECONNREFUSED: #else case ECONNRESET: case ECONNABORTED: case ECONNREFUSED: #endif /* * Connection error; this means the problem is probably * that there's no server set up on the remote machine, * or that it is set up, but it's IPv4-only or IPv6-only * and we're trying the wrong address family. * * These overwrite all other errors, as they indicate * that, even if something else went wrong in another * attempt, this probably wouldn't work even if the * other problems were fixed. */ return (SOCK_CONNERR); #ifdef _WIN32 case WSAENETUNREACH: case WSAETIMEDOUT: case WSAEHOSTDOWN: case WSAEHOSTUNREACH: #else case ENETUNREACH: case ETIMEDOUT: case EHOSTDOWN: case EHOSTUNREACH: #endif /* * Network errors that could be IPv4-specific, IPv6- * specific, or present with both. * * Don't overwrite connection errors, but overwrite * everything else. */ return (SOCK_HOSTERR); #ifdef _WIN32 case WSAENETDOWN: case WSAENETRESET: #else case ENETDOWN: case ENETRESET: #endif /* * Network error; this means we don't know whether * there's a server set up on the remote machine, * and we don't have a reason to believe that IPv6 * any worse or better than IPv4. * * These probably indicate a local failure, e.g. * an interface is down. * * Don't overwrite connection errors or host errors, * but overwrite everything else. */ return (SOCK_NETERR); #ifdef _WIN32 case WSAEAFNOSUPPORT: #else case EAFNOSUPPORT: #endif /* * "Address family not supported" probably means * "No soup^WIPv6 for you!". * * Don't overwrite connection errors, host errors, or * network errors (none of which we should get for this * address family if it's not supported), but overwrite * everything else. */ return (SOCK_AFNOTSUPERR); default: /* * Anything else. * * Don't overwrite any errors. */ return (SOCK_UNKNOWNERR); } } /* * \brief This function initializes the socket mechanism if it hasn't * already been initialized or reinitializes it after it has been * cleaned up. * * On UN*Xes, it doesn't need to do anything; on Windows, it needs to * initialize Winsock. * * \param errbuf: a pointer to an user-allocated buffer that will contain * the complete error message. This buffer has to be at least 'errbuflen' * in length. It can be NULL; in this case no error message is supplied. * * \param errbuflen: length of the buffer that will contains the error. * The error message cannot be larger than 'errbuflen - 1' because the * last char is reserved for the string terminator. * * \return '0' if everything is fine, '-1' if some errors occurred. The * error message is returned in the buffer pointed to by 'errbuf' variable. */ #ifdef _WIN32 int sock_init(char *errbuf, int errbuflen) { if (sockcount == 0) { WSADATA wsaData; /* helper variable needed to initialize Winsock */ if (WSAStartup(MAKEWORD(WINSOCK_MAJOR_VERSION, WINSOCK_MINOR_VERSION), &wsaData) != 0) { if (errbuf) snprintf(errbuf, errbuflen, "Failed to initialize Winsock\n"); return -1; } } sockcount++; return 0; } #else int sock_init(char *errbuf _U_, int errbuflen _U_) { /* * Nothing to do on UN*Xes. */ return 0; } #endif /* * \brief This function cleans up the socket mechanism if we have no * sockets left open. * * On UN*Xes, it doesn't need to do anything; on Windows, it needs * to clean up Winsock. * * \return No error values. */ void sock_cleanup(void) { #ifdef _WIN32 sockcount--; if (sockcount == 0) WSACleanup(); #endif } /* * \brief It checks if the sockaddr variable contains a multicast address. * * \return '0' if the address is multicast, '-1' if it is not. */ static int sock_ismcastaddr(const struct sockaddr *saddr) { if (saddr->sa_family == PF_INET) { const struct sockaddr_in *saddr4 = (const struct sockaddr_in *) saddr; if (IN_MULTICAST(ntohl(saddr4->sin_addr.s_addr))) return 0; else return -1; } else { const struct sockaddr_in6 *saddr6 = (const struct sockaddr_in6 *) saddr; if (IN6_IS_ADDR_MULTICAST(&saddr6->sin6_addr)) return 0; else return -1; } } struct addr_status { struct addrinfo *info; int errcode; sock_errtype errtype; }; /* * Sort by IPv4 address vs. IPv6 address. */ static int compare_addrs_to_try_by_address_family(const void *a, const void *b) { const struct addr_status *addr_a = (const struct addr_status *)a; const struct addr_status *addr_b = (const struct addr_status *)b; return addr_a->info->ai_family - addr_b->info->ai_family; } /* * Sort by error type and, within a given error type, by error code and, * within a given error code, by IPv4 address vs. IPv6 address. */ static int compare_addrs_to_try_by_status(const void *a, const void *b) { const struct addr_status *addr_a = (const struct addr_status *)a; const struct addr_status *addr_b = (const struct addr_status *)b; if (addr_a->errtype == addr_b->errtype) { if (addr_a->errcode == addr_b->errcode) { return addr_a->info->ai_family - addr_b->info->ai_family; } return addr_a->errcode - addr_b->errcode; } return addr_a->errtype - addr_b->errtype; } static PCAP_SOCKET sock_create_socket(struct addrinfo *addrinfo, char *errbuf, int errbuflen) { PCAP_SOCKET sock; #ifdef SO_NOSIGPIPE int on = 1; #endif sock = socket(addrinfo->ai_family, addrinfo->ai_socktype, addrinfo->ai_protocol); if (sock == INVALID_SOCKET) { sock_geterrmsg(errbuf, errbuflen, "socket() failed"); return INVALID_SOCKET; } /* * Disable SIGPIPE, if we have SO_NOSIGPIPE. We don't want to * have to deal with signals if the peer closes the connection, * especially in client programs, which may not even be aware that * they're sending to sockets. */ #ifdef SO_NOSIGPIPE if (setsockopt(sock, SOL_SOCKET, SO_NOSIGPIPE, (char *)&on, sizeof (int)) == -1) { sock_geterrmsg(errbuf, errbuflen, "setsockopt(SO_NOSIGPIPE) failed"); closesocket(sock); return INVALID_SOCKET; } #endif return sock; } /* * \brief It initializes a network connection both from the client and the server side. * * In case of a client socket, this function calls socket() and connect(). * In the meanwhile, it checks for any socket error. * If an error occurs, it writes the error message into 'errbuf'. * * In case of a server socket, the function calls socket(), bind() and listen(). * * This function is usually preceded by the sock_initaddress(). * * \param host: for client sockets, the host name to which we're trying * to connect. * * \param addrinfo: pointer to an addrinfo variable which will be used to * open the socket and such. This variable is the one returned by the previous call to * sock_initaddress(). * * \param server: '1' if this is a server socket, '0' otherwise. * * \param nconn: number of the connections that are allowed to wait into the listen() call. * This value has no meanings in case of a client socket. * * \param errbuf: a pointer to an user-allocated buffer that will contain the complete * error message. This buffer has to be at least 'errbuflen' in length. * It can be NULL; in this case the error cannot be printed. * * \param errbuflen: length of the buffer that will contains the error. The error message cannot be * larger than 'errbuflen - 1' because the last char is reserved for the string terminator. * * \return the socket that has been opened (that has to be used in the following sockets calls) * if everything is fine, INVALID_SOCKET if some errors occurred. The error message is returned * in the 'errbuf' variable. */ PCAP_SOCKET sock_open(const char *host, struct addrinfo *addrinfo, int server, int nconn, char *errbuf, int errbuflen) { PCAP_SOCKET sock; /* This is a server socket */ if (server) { int on; /* * Attempt to create the socket. */ sock = sock_create_socket(addrinfo, errbuf, errbuflen); if (sock == INVALID_SOCKET) { return INVALID_SOCKET; } /* * Allow a new server to bind the socket after the old one * exited, even if lingering sockets are still present. * * Don't treat an error as a failure. */ on = 1; (void)setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (char *)&on, sizeof (on)); #if defined(IPV6_V6ONLY) || defined(IPV6_BINDV6ONLY) /* * Force the use of IPv6-only addresses. * * RFC 3493 indicates that you can support IPv4 on an * IPv6 socket: * * https://tools.ietf.org/html/rfc3493#section-3.7 * * and that this is the default behavior. This means * that if we first create an IPv6 socket bound to the * "any" address, it is, in effect, also bound to the * IPv4 "any" address, so when we create an IPv4 socket * and try to bind it to the IPv4 "any" address, it gets * EADDRINUSE. * * Not all network stacks support IPv4 on IPv6 sockets; * pre-NT 6 Windows stacks don't support it, and the * OpenBSD stack doesn't support it for security reasons * (see the OpenBSD inet6(4) man page). Therefore, we * don't want to rely on this behavior. * * So we try to disable it, using either the IPV6_V6ONLY * option from RFC 3493: * * https://tools.ietf.org/html/rfc3493#section-5.3 * * or the IPV6_BINDV6ONLY option from older UN*Xes. */ #ifndef IPV6_V6ONLY /* For older systems */ #define IPV6_V6ONLY IPV6_BINDV6ONLY #endif /* IPV6_V6ONLY */ if (addrinfo->ai_family == PF_INET6) { on = 1; if (setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, (char *)&on, sizeof (int)) == -1) { if (errbuf) snprintf(errbuf, errbuflen, "setsockopt(IPV6_V6ONLY)"); closesocket(sock); return INVALID_SOCKET; } } #endif /* defined(IPV6_V6ONLY) || defined(IPV6_BINDV6ONLY) */ /* WARNING: if the address is a mcast one, I should place the proper Win32 code here */ if (bind(sock, addrinfo->ai_addr, (int) addrinfo->ai_addrlen) != 0) { sock_geterrmsg(errbuf, errbuflen, "bind() failed"); closesocket(sock); return INVALID_SOCKET; } if (addrinfo->ai_socktype == SOCK_STREAM) if (listen(sock, nconn) == -1) { sock_geterrmsg(errbuf, errbuflen, "listen() failed"); closesocket(sock); return INVALID_SOCKET; } /* server side ended */ return sock; } else /* we're the client */ { struct addr_status *addrs_to_try; struct addrinfo *tempaddrinfo; size_t numaddrinfos; size_t i; int current_af = AF_UNSPEC; /* * We have to loop though all the addrinfos returned. * For instance, we can have both IPv6 and IPv4 addresses, * but the service we're trying to connect to is unavailable * in IPv6, so we have to try in IPv4 as well. * * How many addrinfos do we have? */ numaddrinfos = 0; for (tempaddrinfo = addrinfo; tempaddrinfo != NULL; tempaddrinfo = tempaddrinfo->ai_next) { numaddrinfos++; } if (numaddrinfos == 0) { snprintf(errbuf, errbuflen, "There are no addresses in the address list"); return INVALID_SOCKET; } /* * Allocate an array of struct addr_status and fill it in. */ addrs_to_try = calloc(numaddrinfos, sizeof *addrs_to_try); if (addrs_to_try == NULL) { snprintf(errbuf, errbuflen, "Out of memory connecting to %s", host); return INVALID_SOCKET; } for (tempaddrinfo = addrinfo, i = 0; tempaddrinfo != NULL; tempaddrinfo = tempaddrinfo->ai_next, i++) { addrs_to_try[i].info = tempaddrinfo; addrs_to_try[i].errcode = 0; addrs_to_try[i].errtype = SOCK_NOERR; } /* * Sort the structures to put the IPv4 addresses before the * IPv6 addresses; we will have to create an IPv4 socket * for the IPv4 addresses and an IPv6 socket for the IPv6 * addresses (one of the arguments to socket() is the * address/protocol family to use, and IPv4 and IPv6 are * separate address/protocol families). */ qsort(addrs_to_try, numaddrinfos, sizeof *addrs_to_try, compare_addrs_to_try_by_address_family); /* Start out with no socket. */ sock = INVALID_SOCKET; /* * Now try them all. */ for (i = 0; i < numaddrinfos; i++) { tempaddrinfo = addrs_to_try[i].info; #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION break; #endif /* * If we have a socket, but it's for a * different address family, close it. */ if (sock != INVALID_SOCKET && current_af != tempaddrinfo->ai_family) { closesocket(sock); sock = INVALID_SOCKET; } /* * If we don't have a socket, open one * for *this* address's address family. */ if (sock == INVALID_SOCKET) { sock = sock_create_socket(tempaddrinfo, errbuf, errbuflen); if (sock == INVALID_SOCKET) { free(addrs_to_try); return INVALID_SOCKET; } } if (connect(sock, tempaddrinfo->ai_addr, (int) tempaddrinfo->ai_addrlen) == -1) { addrs_to_try[i].errcode = sock_geterrcode(); addrs_to_try[i].errtype = sock_geterrtype(addrs_to_try[i].errcode); } else break; } /* * Check how we exited from the previous loop. * If tempaddrinfo is equal to NULL, it means that all * the connect() attempts failed. Construct an * error message. */ if (i == numaddrinfos) { int same_error_for_all; int first_error; closesocket(sock); /* * Sort the statuses to group together categories * of errors, errors within categories, and * address families within error sets. */ qsort(addrs_to_try, numaddrinfos, sizeof *addrs_to_try, compare_addrs_to_try_by_status); /* * Are all the errors the same? */ same_error_for_all = 1; first_error = addrs_to_try[0].errcode; for (i = 1; i < numaddrinfos; i++) { if (addrs_to_try[i].errcode != first_error) { same_error_for_all = 0; break; } } if (same_error_for_all) { /* * Yes. No need to show the IP * addresses. */ if (addrs_to_try[0].errtype == SOCK_CONNERR) { /* * Connection error; note that * the daemon might not be set * up correctly, or set up at all. */ sock_fmterrmsg(errbuf, errbuflen, addrs_to_try[0].errcode, "Is the server properly installed? Cannot connect to %s", host); } else { sock_fmterrmsg(errbuf, errbuflen, addrs_to_try[0].errcode, "Cannot connect to %s", host); } } else { /* * Show all the errors and the IP addresses * to which they apply. */ char *errbufptr; size_t bufspaceleft; size_t msglen; snprintf(errbuf, errbuflen, "Connect to %s failed: ", host); msglen = strlen(errbuf); errbufptr = errbuf + msglen; bufspaceleft = errbuflen - msglen; for (i = 0; i < numaddrinfos && addrs_to_try[i].errcode != SOCK_NOERR; i++) { /* * Get the string for the address * and port that got this error. */ sock_getascii_addrport((struct sockaddr_storage *) addrs_to_try[i].info->ai_addr, errbufptr, (int)bufspaceleft, NULL, 0, NI_NUMERICHOST, NULL, 0); msglen = strlen(errbuf); errbufptr = errbuf + msglen; bufspaceleft = errbuflen - msglen; if (i + 1 < numaddrinfos && addrs_to_try[i + 1].errcode == addrs_to_try[i].errcode) { /* * There's another error * after this, and it has * the same error code. * * Append a comma, as the * list of addresses with * this error has another * entry. */ snprintf(errbufptr, bufspaceleft, ", "); } else { /* * Either there are no * more errors after this, * or the next error is * different. * * Append a colon and * the message for tis * error, followed by a * comma if there are * more errors. */ sock_fmterrmsg(errbufptr, bufspaceleft, addrs_to_try[i].errcode, "%s", ""); msglen = strlen(errbuf); errbufptr = errbuf + msglen; bufspaceleft = errbuflen - msglen; if (i + 1 < numaddrinfos && addrs_to_try[i + 1].errcode != SOCK_NOERR) { /* * More to come. */ snprintf(errbufptr, bufspaceleft, ", "); } } msglen = strlen(errbuf); errbufptr = errbuf + msglen; bufspaceleft = errbuflen - msglen; } } free(addrs_to_try); return INVALID_SOCKET; } else { free(addrs_to_try); return sock; } } } /* * \brief Closes the present (TCP and UDP) socket connection. * * This function sends a shutdown() on the socket in order to disable send() calls * (while recv() ones are still allowed). Then, it closes the socket. * * \param sock: the socket identifier of the connection that has to be closed. * * \param errbuf: a pointer to an user-allocated buffer that will contain the complete * error message. This buffer has to be at least 'errbuflen' in length. * It can be NULL; in this case the error cannot be printed. * * \param errbuflen: length of the buffer that will contains the error. The error message cannot be * larger than 'errbuflen - 1' because the last char is reserved for the string terminator. * * \return '0' if everything is fine, '-1' if some errors occurred. The error message is returned * in the 'errbuf' variable. */ int sock_close(PCAP_SOCKET sock, char *errbuf, int errbuflen) { /* * SHUT_WR: subsequent calls to the send function are disallowed. * For TCP sockets, a FIN will be sent after all data is sent and * acknowledged by the Server. */ if (shutdown(sock, SHUT_WR)) { sock_geterrmsg(errbuf, errbuflen, "shutdown() failed"); /* close the socket anyway */ closesocket(sock); return -1; } closesocket(sock); return 0; } /* * gai_strerror() has some problems: * * 1) on Windows, Microsoft explicitly says it's not thread-safe; * 2) on UN*X, the Single UNIX Specification doesn't say it *is* * thread-safe, so an implementation might use a static buffer * for unknown error codes; * 3) the error message for the most likely error, EAI_NONAME, is * truly horrible on several platforms ("nodename nor servname * provided, or not known"? It's typically going to be "not * known", not "oopsie, I passed null pointers for the host name * and service name", not to mention they forgot the "neither"); * * so we roll our own. */ static void get_gai_errstring(char *errbuf, int errbuflen, const char *prefix, int err, const char *hostname, const char *portname) { char hostport[PCAP_ERRBUF_SIZE]; if (hostname != NULL && portname != NULL) snprintf(hostport, PCAP_ERRBUF_SIZE, "host and port %s:%s", hostname, portname); else if (hostname != NULL) snprintf(hostport, PCAP_ERRBUF_SIZE, "host %s", hostname); else if (portname != NULL) snprintf(hostport, PCAP_ERRBUF_SIZE, "port %s", portname); else snprintf(hostport, PCAP_ERRBUF_SIZE, ""); switch (err) { #ifdef EAI_ADDRFAMILY case EAI_ADDRFAMILY: snprintf(errbuf, errbuflen, "%sAddress family for %s not supported", prefix, hostport); break; #endif case EAI_AGAIN: snprintf(errbuf, errbuflen, "%s%s could not be resolved at this time", prefix, hostport); break; case EAI_BADFLAGS: snprintf(errbuf, errbuflen, "%sThe ai_flags parameter for looking up %s had an invalid value", prefix, hostport); break; case EAI_FAIL: snprintf(errbuf, errbuflen, "%sA non-recoverable error occurred when attempting to resolve %s", prefix, hostport); break; case EAI_FAMILY: snprintf(errbuf, errbuflen, "%sThe address family for looking up %s was not recognized", prefix, hostport); break; case EAI_MEMORY: snprintf(errbuf, errbuflen, "%sOut of memory trying to allocate storage when looking up %s", prefix, hostport); break; /* * RFC 2553 had both EAI_NODATA and EAI_NONAME. * * RFC 3493 has only EAI_NONAME. * * Some implementations define EAI_NODATA and EAI_NONAME * to the same value, others don't. If EAI_NODATA is * defined and isn't the same as EAI_NONAME, we handle * EAI_NODATA. */ #if defined(EAI_NODATA) && EAI_NODATA != EAI_NONAME case EAI_NODATA: snprintf(errbuf, errbuflen, "%sNo address associated with %s", prefix, hostport); break; #endif case EAI_NONAME: snprintf(errbuf, errbuflen, "%sThe %s couldn't be resolved", prefix, hostport); break; case EAI_SERVICE: snprintf(errbuf, errbuflen, "%sThe service value specified when looking up %s as not recognized for the socket type", prefix, hostport); break; case EAI_SOCKTYPE: snprintf(errbuf, errbuflen, "%sThe socket type specified when looking up %s as not recognized", prefix, hostport); break; #ifdef EAI_SYSTEM case EAI_SYSTEM: /* * Assumed to be UN*X. */ pcapint_fmt_errmsg_for_errno(errbuf, errbuflen, errno, "%sAn error occurred when looking up %s", prefix, hostport); break; #endif #ifdef EAI_BADHINTS case EAI_BADHINTS: snprintf(errbuf, errbuflen, "%sInvalid value for hints when looking up %s", prefix, hostport); break; #endif #ifdef EAI_PROTOCOL case EAI_PROTOCOL: snprintf(errbuf, errbuflen, "%sResolved protocol when looking up %s is unknown", prefix, hostport); break; #endif #ifdef EAI_OVERFLOW case EAI_OVERFLOW: snprintf(errbuf, errbuflen, "%sArgument buffer overflow when looking up %s", prefix, hostport); break; #endif default: snprintf(errbuf, errbuflen, "%sgetaddrinfo() error %d when looking up %s", prefix, err, hostport); break; } } /* * \brief Checks that the address, port and flags given are valid and it returns an 'addrinfo' structure. * * This function basically calls the getaddrinfo() calls, and it performs a set of sanity checks * to control that everything is fine (e.g. a TCP socket cannot have a mcast address, and such). * If an error occurs, it writes the error message into 'errbuf'. * * \param host: a pointer to a string identifying the host. It can be * a host name, a numeric literal address, or NULL or "" (useful * in case of a server socket which has to bind to all addresses). * * \param port: a pointer to a user-allocated buffer containing the network port to use. * * \param hints: an addrinfo variable (passed by reference) containing the flags needed to create the * addrinfo structure appropriately. * * \param addrinfo: it represents the true returning value. This is a pointer to an addrinfo variable * (passed by reference), which will be allocated by this function and returned back to the caller. * This variable will be used in the next sockets calls. * * \param errbuf: a pointer to an user-allocated buffer that will contain the complete * error message. This buffer has to be at least 'errbuflen' in length. * It can be NULL; in this case the error cannot be printed. * * \param errbuflen: length of the buffer that will contains the error. The error message cannot be * larger than 'errbuflen - 1' because the last char is reserved for the string terminator. * * \return a pointer to the first element in a list of addrinfo structures * if everything is fine, NULL if some errors occurred. The error message * is returned in the 'errbuf' variable. * * \warning The list of addrinfo structures returned has to be deleted by * the programmer by calling freeaddrinfo() when it is no longer needed. * * \warning This function requires the 'hints' variable as parameter. The semantic of this variable is the same * of the one of the corresponding variable used into the standard getaddrinfo() socket function. We suggest * the programmer to look at that function in order to set the 'hints' variable appropriately. */ struct addrinfo *sock_initaddress(const char *host, const char *port, struct addrinfo *hints, char *errbuf, int errbuflen) { struct addrinfo *addrinfo; int retval; /* * We allow both the host and port to be null, but getaddrinfo() * is not guaranteed to do so; to handle that, if port is null, * we provide "0" as the port number. * * This results in better error messages from get_gai_errstring(), * as those messages won't talk about a problem with the port if * no port was specified. */ retval = getaddrinfo(host, port == NULL ? "0" : port, hints, &addrinfo); if (retval != 0) { /* * That call failed. * Determine whether the problem is that the host is bad. */ if (errbuf) { if (host != NULL && port != NULL) { /* * Try with just a host, to distinguish * between "host is bad" and "port is * bad". */ int try_retval; try_retval = getaddrinfo(host, NULL, hints, &addrinfo); if (try_retval == 0) { /* * Worked with just the host, * so assume the problem is * with the port. * * Free up the address info first. */ freeaddrinfo(addrinfo); get_gai_errstring(errbuf, errbuflen, "", retval, NULL, port); } else { /* * Didn't work with just the host, * so assume the problem is * with the host; we assume * the original error indicates * the underlying problem. */ get_gai_errstring(errbuf, errbuflen, "", retval, host, NULL); } } else { /* * Either the host or port was null, so * there's nothing to determine; report * the error from the original call. */ get_gai_errstring(errbuf, errbuflen, "", retval, host, port); } } return NULL; } /* * \warning SOCKET: I should check all the accept() in order to bind to all addresses in case * addrinfo has more han one pointers */ /* * This software only supports PF_INET and PF_INET6. * * XXX - should we just check that at least *one* address is * either PF_INET or PF_INET6, and, when using the list, * ignore all addresses that are neither? (What, no IPX * support? :-)) */ if ((addrinfo->ai_family != PF_INET) && (addrinfo->ai_family != PF_INET6)) { if (errbuf) snprintf(errbuf, errbuflen, "getaddrinfo(): socket type not supported"); freeaddrinfo(addrinfo); return NULL; } /* * You can't do multicast (or broadcast) TCP. */ if ((addrinfo->ai_socktype == SOCK_STREAM) && (sock_ismcastaddr(addrinfo->ai_addr) == 0)) { if (errbuf) snprintf(errbuf, errbuflen, "getaddrinfo(): multicast addresses are not valid when using TCP streams"); freeaddrinfo(addrinfo); return NULL; } return addrinfo; } /* * \brief It sends the amount of data contained into 'buffer' on the given socket. * * This function basically calls the send() socket function and it checks that all * the data specified in 'buffer' (of size 'size') will be sent. If an error occurs, * it writes the error message into 'errbuf'. * In case the socket buffer does not have enough space, it loops until all data * has been sent. * * \param socket: the connected socket currently opened. * * \param buffer: a char pointer to a user-allocated buffer in which data is contained. * * \param size: number of bytes that have to be sent. * * \param errbuf: a pointer to an user-allocated buffer that will contain the complete * error message. This buffer has to be at least 'errbuflen' in length. * It can be NULL; in this case the error cannot be printed. * * \param errbuflen: length of the buffer that will contains the error. The error message cannot be * larger than 'errbuflen - 1' because the last char is reserved for the string terminator. * * \return '0' if everything is fine, '-1' if an error other than * "connection reset" or "peer has closed the receive side" occurred, * '-2' if we got one of those errors. * For errors, an error message is returned in the 'errbuf' variable. */ int sock_send(PCAP_SOCKET sock, SSL *ssl _U_NOSSL_, const char *buffer, size_t size, char *errbuf, int errbuflen) { int remaining; ssize_t nsent; if (size > INT_MAX) { if (errbuf) { snprintf(errbuf, errbuflen, "Can't send more than %u bytes with sock_send", INT_MAX); } return -1; } remaining = (int)size; do { #ifdef HAVE_OPENSSL if (ssl) return ssl_send(ssl, buffer, remaining, errbuf, errbuflen); #endif #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION nsent = remaining; #else #ifdef MSG_NOSIGNAL /* * Send with MSG_NOSIGNAL, so that we don't get SIGPIPE * on errors on stream-oriented sockets when the other * end breaks the connection. * The EPIPE error is still returned. */ nsent = send(sock, buffer, remaining, MSG_NOSIGNAL); #else nsent = send(sock, buffer, remaining, 0); #endif #endif //FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION if (nsent == -1) { /* * If the client closed the connection out from * under us, there's no need to log that as an * error. */ int errcode; #ifdef _WIN32 errcode = GetLastError(); if (errcode == WSAECONNRESET || errcode == WSAECONNABORTED) { /* * WSAECONNABORTED appears to be the error * returned in Winsock when you try to send * on a connection where the peer has closed * the receive side. */ return -2; } sock_fmterrmsg(errbuf, errbuflen, errcode, "send() failed"); #else errcode = errno; if (errcode == ECONNRESET || errcode == EPIPE) { /* * EPIPE is what's returned on UN*X when * you try to send on a connection when * the peer has closed the receive side. */ return -2; } sock_fmterrmsg(errbuf, errbuflen, errcode, "send() failed"); #endif return -1; } remaining -= nsent; buffer += nsent; } while (remaining != 0); return 0; } /* * \brief It copies the amount of data contained in 'data' into 'outbuf'. * and it checks for buffer overflows. * * This function basically copies 'size' bytes of data contained in 'data' * into 'outbuf', starting at offset 'offset'. Before that, it checks that the * resulting buffer will not be larger than 'totsize'. Finally, it updates * the 'offset' variable in order to point to the first empty location of the buffer. * * In case the function is called with 'checkonly' equal to 1, it does not copy * the data into the buffer. It only checks for buffer overflows and it updates the * 'offset' variable. This mode can be useful when the buffer already contains the * data (maybe because the producer writes directly into the target buffer), so * only the buffer overflow check has to be made. * In this case, both 'data' and 'outbuf' can be NULL values. * * This function is useful in case the userland application does not know immediately * all the data it has to write into the socket. This function provides a way to create * the "stream" step by step, appending the new data to the old one. Then, when all the * data has been bufferized, the application can call the sock_send() function. * * \param data: a void pointer to the data that has to be copied. * * \param size: number of bytes that have to be copied. * * \param outbuf: user-allocated buffer (of size 'totsize') into which data * has to be copied. * * \param offset: an index into 'outbuf' which keeps the location of its first * empty location. * * \param totsize: total size of the buffer into which data is being copied. * * \param checkonly: '1' if we do not want to copy data into the buffer and we * want just do a buffer overflow control, '0' if data has to be copied as well. * * \param errbuf: a pointer to an user-allocated buffer that will contain the complete * error message. This buffer has to be at least 'errbuflen' in length. * It can be NULL; in this case the error cannot be printed. * * \param errbuflen: length of the buffer that will contains the error. The error message cannot be * larger than 'errbuflen - 1' because the last char is reserved for the string terminator. * * \return '0' if everything is fine, '-1' if some errors occurred. The error message * is returned in the 'errbuf' variable. When the function returns, 'outbuf' will * have the new string appended, and 'offset' will keep the length of that buffer. * In case of 'checkonly == 1', data is not copied, but 'offset' is updated in any case. * * \warning This function assumes that the buffer in which data has to be stored is * large 'totbuf' bytes. * * \warning In case of 'checkonly', be carefully to call this function *before* copying * the data into the buffer. Otherwise, the control about the buffer overflow is useless. */ int sock_bufferize(const void *data, int size, char *outbuf, int *offset, int totsize, int checkonly, char *errbuf, int errbuflen) { if ((*offset + size) > totsize) { if (errbuf) snprintf(errbuf, errbuflen, "Not enough space in the temporary send buffer."); return -1; } if (!checkonly) memcpy(outbuf + (*offset), data, size); (*offset) += size; return 0; } /* * \brief It waits on a connected socket and it manages to receive data. * * This function basically calls the recv() socket function and it checks that no * error occurred. If that happens, it writes the error message into 'errbuf'. * * This function changes its behavior according to the 'receiveall' flag: if we * want to receive exactly 'size' byte, it loops on the recv() until all the requested * data is arrived. Otherwise, it returns the data currently available. * * In case the socket does not have enough data available, it cycles on the recv() * until the requested data (of size 'size') is arrived. * In this case, it blocks until the number of bytes read is equal to 'size'. * * \param sock: the connected socket currently opened. * * \param buffer: a char pointer to a user-allocated buffer in which data has to be stored * * \param size: size of the allocated buffer. WARNING: this indicates the number of bytes * that we are expecting to be read. * * \param flags: * * SOCK_RECEIVALL_XXX: * * if SOCK_RECEIVEALL_NO, return as soon as some data is ready * if SOCK_RECEIVALL_YES, wait until 'size' data has been * received (in case the socket does not have enough data available). * * SOCK_EOF_XXX: * * if SOCK_EOF_ISNT_ERROR, if the first read returns 0, just return 0, * and return an error on any subsequent read that returns 0; * if SOCK_EOF_IS_ERROR, if any read returns 0, return an error. * * \param errbuf: a pointer to an user-allocated buffer that will contain the complete * error message. This buffer has to be at least 'errbuflen' in length. * It can be NULL; in this case the error cannot be printed. * * \param errbuflen: length of the buffer that will contains the error. The error message cannot be * larger than 'errbuflen - 1' because the last char is reserved for the string terminator. * * \return the number of bytes read if everything is fine, '-1' if some errors occurred. * The error message is returned in the 'errbuf' variable. */ int sock_recv(PCAP_SOCKET sock, SSL *ssl _U_NOSSL_, void *buffer, size_t size, int flags, char *errbuf, int errbuflen) { int recv_flags = 0; char *bufp = buffer; int remaining; ssize_t nread; if (size == 0) { return 0; } if (size > INT_MAX) { if (errbuf) { snprintf(errbuf, errbuflen, "Can't read more than %u bytes with sock_recv", INT_MAX); } return -1; } if (flags & SOCK_MSG_PEEK) recv_flags |= MSG_PEEK; bufp = (char *) buffer; remaining = (int) size; /* * We don't use MSG_WAITALL because it's not supported in * Win32. */ for (;;) { #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION nread = fuzz_recv(bufp, remaining); #elif defined(HAVE_OPENSSL) if (ssl) { /* * XXX - what about MSG_PEEK? */ nread = ssl_recv(ssl, bufp, remaining, errbuf, errbuflen); if (nread == -2) return -1; } else nread = recv(sock, bufp, remaining, recv_flags); #else nread = recv(sock, bufp, remaining, recv_flags); #endif if (nread == -1) { #ifndef _WIN32 if (errno == EINTR) return -3; #endif sock_geterrmsg(errbuf, errbuflen, "recv() failed"); return -1; } if (nread == 0) { if ((flags & SOCK_EOF_IS_ERROR) || (remaining != (int) size)) { /* * Either we've already read some data, * or we're always supposed to return * an error on EOF. */ if (errbuf) { snprintf(errbuf, errbuflen, "The other host terminated the connection."); } return -1; } else return 0; } /* * Do we want to read the amount requested, or just return * what we got? */ if (!(flags & SOCK_RECEIVEALL_YES)) { /* * Just return what we got. */ return (int) nread; } bufp += nread; remaining -= nread; if (remaining == 0) return (int) size; } } /* * Receives a datagram from a socket. * * Returns the size of the datagram on success or -1 on error. */ int sock_recv_dgram(PCAP_SOCKET sock, SSL *ssl _U_NOSSL_, void *buffer, size_t size, char *errbuf, int errbuflen) { ssize_t nread; #ifndef _WIN32 struct msghdr message; struct iovec iov; #endif if (size == 0) { return 0; } if (size > INT_MAX) { if (errbuf) { snprintf(errbuf, errbuflen, "Can't read more than %u bytes with sock_recv_dgram", INT_MAX); } return -1; } #ifdef HAVE_OPENSSL // TODO: DTLS if (ssl) { snprintf(errbuf, errbuflen, "DTLS not implemented yet"); return -1; } #endif /* * This should be a datagram socket, so we should get the * entire datagram in one recv() or recvmsg() call, and * don't need to loop. */ #ifdef _WIN32 nread = recv(sock, buffer, (int)size, 0); if (nread == SOCKET_ERROR) { /* * To quote the MSDN documentation for recv(), * "If the datagram or message is larger than * the buffer specified, the buffer is filled * with the first part of the datagram, and recv * generates the error WSAEMSGSIZE. For unreliable * protocols (for example, UDP) the excess data is * lost..." * * So if the message is bigger than the buffer * supplied to us, the excess data is discarded, * and we'll report an error. */ sock_fmterrmsg(errbuf, errbuflen, sock_geterrcode(), "recv() failed"); return -1; } #else /* _WIN32 */ /* * The Single UNIX Specification says that a recv() on * a socket for a message-oriented protocol will discard * the excess data. It does *not* indicate that the * receive will fail with, for example, EMSGSIZE. * * Therefore, we use recvmsg(), which appears to be * the only way to get a "message truncated" indication * when receiving a message for a message-oriented * protocol. */ message.msg_name = NULL; /* we don't care who it's from */ message.msg_namelen = 0; iov.iov_base = buffer; iov.iov_len = size; message.msg_iov = &iov; message.msg_iovlen = 1; #ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL message.msg_control = NULL; /* we don't care about control information */ message.msg_controllen = 0; #endif #ifdef HAVE_STRUCT_MSGHDR_MSG_FLAGS message.msg_flags = 0; #endif #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION nread = fuzz_recv(buffer, size); #else nread = recvmsg(sock, &message, 0); #endif if (nread == -1) { if (errno == EINTR) return -3; sock_geterrmsg(errbuf, errbuflen, "recv() failed"); return -1; } #ifdef HAVE_STRUCT_MSGHDR_MSG_FLAGS /* * XXX - Solaris supports this, but only if you ask for the * X/Open version of recvmsg(); should we use that, or will * that cause other problems? */ if (message.msg_flags & MSG_TRUNC) { /* * Message was bigger than the specified buffer size. * * Report this as an error, as the Microsoft documentation * implies we'd do in a similar case on Windows. */ snprintf(errbuf, errbuflen, "recv(): Message too long"); return -1; } #endif /* HAVE_STRUCT_MSGHDR_MSG_FLAGS */ #endif /* _WIN32 */ /* * The size we're reading fits in an int, so the return value * will fit in an int. */ return (int)nread; } /* * \brief It discards N bytes that are currently waiting to be read on the current socket. * * This function is useful in case we receive a message we cannot understand (e.g. * wrong version number when receiving a network packet), so that we have to discard all * data before reading a new message. * * This function will read 'size' bytes from the socket and discard them. * It defines an internal buffer in which data will be copied; however, in case * this buffer is not large enough, it will cycle in order to read everything as well. * * \param sock: the connected socket currently opened. * * \param size: number of bytes that have to be discarded. * * \param errbuf: a pointer to an user-allocated buffer that will contain the complete * error message. This buffer has to be at least 'errbuflen' in length. * It can be NULL; in this case the error cannot be printed. * * \param errbuflen: length of the buffer that will contains the error. The error message cannot be * larger than 'errbuflen - 1' because the last char is reserved for the string terminator. * * \return '0' if everything is fine, '-1' if some errors occurred. * The error message is returned in the 'errbuf' variable. */ int sock_discard(PCAP_SOCKET sock, SSL *ssl, int size, char *errbuf, int errbuflen) { #define TEMP_BUF_SIZE 32768 char buffer[TEMP_BUF_SIZE]; /* network buffer, to be used when the message is discarded */ /* * A static allocation avoids the need of a 'malloc()' each time we want to discard a message * Our feeling is that a buffer if 32KB is enough for most of the application; * in case this is not enough, the "while" loop discards the message by calling the * sockrecv() several times. * We do not want to create a bigger variable because this causes the program to exit on * some platforms (e.g. BSD) */ while (size > TEMP_BUF_SIZE) { if (sock_recv(sock, ssl, buffer, TEMP_BUF_SIZE, SOCK_RECEIVEALL_YES, errbuf, errbuflen) == -1) return -1; size -= TEMP_BUF_SIZE; } /* * If there is still data to be discarded * In this case, the data can fit into the temporary buffer */ if (size) { if (sock_recv(sock, ssl, buffer, size, SOCK_RECEIVEALL_YES, errbuf, errbuflen) == -1) return -1; } return 0; } /* * \brief Checks that one host (identified by the sockaddr_storage structure) belongs to an 'allowed list'. * * This function is useful after an accept() call in order to check if the connecting * host is allowed to connect to me. To do that, we have a buffer that keeps the list of the * allowed host; this function checks the sockaddr_storage structure of the connecting host * against this host list, and it returns '0' is the host is included in this list. * * \param hostlist: pointer to a string that contains the list of the allowed host. * * \param sep: a string that keeps the separators used between the hosts (for example the * space character) in the host list. * * \param from: a sockaddr_storage structure, as it is returned by the accept() call. * * \param errbuf: a pointer to an user-allocated buffer that will contain the complete * error message. This buffer has to be at least 'errbuflen' in length. * It can be NULL; in this case the error cannot be printed. * * \param errbuflen: length of the buffer that will contains the error. The error message cannot be * larger than 'errbuflen - 1' because the last char is reserved for the string terminator. * * \return It returns: * - '1' if the host list is empty * - '0' if the host belongs to the host list (and therefore it is allowed to connect) * - '-1' in case the host does not belong to the host list (and therefore it is not allowed to connect * - '-2' in case or error. The error message is returned in the 'errbuf' variable. */ int sock_check_hostlist(const char *hostlist, const char *sep, struct sockaddr_storage *from, char *errbuf, int errbuflen) { /* checks if the connecting host is among the ones allowed */ if ((hostlist) && (hostlist[0])) { char *token; /* temp, needed to separate items into the hostlist */ struct addrinfo *addrinfo, *ai_next; char *temphostlist; char *lasts; int getaddrinfo_failed = 0; /* * The problem is that strtok modifies the original variable by putting '0' at the end of each token * So, we have to create a new temporary string in which the original content is kept */ temphostlist = strdup(hostlist); if (temphostlist == NULL) { sock_geterrmsg(errbuf, errbuflen, "sock_check_hostlist(), malloc() failed"); return -2; } token = pcapint_strtok_r(temphostlist, sep, &lasts); /* it avoids a warning in the compilation ('addrinfo used but not initialized') */ addrinfo = NULL; while (token != NULL) { struct addrinfo hints; int retval; addrinfo = NULL; memset(&hints, 0, sizeof(struct addrinfo)); hints.ai_family = PF_UNSPEC; hints.ai_socktype = SOCK_STREAM; retval = getaddrinfo(token, NULL, &hints, &addrinfo); if (retval != 0) { if (errbuf) get_gai_errstring(errbuf, errbuflen, "Allowed host list error: ", retval, token, NULL); /* * Note that at least one call to getaddrinfo() * failed. */ getaddrinfo_failed = 1; /* Get next token */ token = pcapint_strtok_r(NULL, sep, &lasts); continue; } /* ai_next is required to preserve the content of addrinfo, in order to deallocate it properly */ ai_next = addrinfo; while (ai_next) { if (sock_cmpaddr(from, (struct sockaddr_storage *) ai_next->ai_addr) == 0) { free(temphostlist); freeaddrinfo(addrinfo); return 0; } /* * If we are here, it means that the current address does not matches * Let's try with the next one in the header chain */ ai_next = ai_next->ai_next; } freeaddrinfo(addrinfo); addrinfo = NULL; /* Get next token */ token = pcapint_strtok_r(NULL, sep, &lasts); } if (addrinfo) { freeaddrinfo(addrinfo); addrinfo = NULL; } free(temphostlist); if (getaddrinfo_failed) { /* * At least one getaddrinfo() call failed; * treat that as an error, so rpcapd knows * that it should log it locally as well * as telling the client about it. */ return -2; } else { /* * All getaddrinfo() calls succeeded, but * the host wasn't in the list. */ if (errbuf) snprintf(errbuf, errbuflen, "The host is not in the allowed host list. Connection refused."); return -1; } } /* No hostlist, so we have to return 'empty list' */ return 1; } /* * \brief Compares two addresses contained into two sockaddr_storage structures. * * This function is useful to compare two addresses, given their internal representation, * i.e. an sockaddr_storage structure. * * The two structures do not need to be sockaddr_storage; you can have both 'sockaddr_in' and * sockaddr_in6, properly casted in order to be compliant to the function interface. * * This function will return '0' if the two addresses matches, '-1' if not. * * \param first: a sockaddr_storage structure, (for example the one that is returned by an * accept() call), containing the first address to compare. * * \param second: a sockaddr_storage structure containing the second address to compare. * * \return '0' if the addresses are equal, '-1' if they are different. */ int sock_cmpaddr(struct sockaddr_storage *first, struct sockaddr_storage *second) { if (first->ss_family == second->ss_family) { if (first->ss_family == AF_INET) { if (memcmp(&(((struct sockaddr_in *) first)->sin_addr), &(((struct sockaddr_in *) second)->sin_addr), sizeof(struct in_addr)) == 0) return 0; } else /* address family is AF_INET6 */ { if (memcmp(&(((struct sockaddr_in6 *) first)->sin6_addr), &(((struct sockaddr_in6 *) second)->sin6_addr), sizeof(struct in6_addr)) == 0) return 0; } } return -1; } /* * \brief It gets the address/port the system picked for this socket (on connected sockets). * * It is used to return the address and port the server picked for our socket on the local machine. * It works only on: * - connected sockets * - server sockets * * On unconnected client sockets it does not work because the system dynamically chooses a port * only when the socket calls a send() call. * * \param sock: the connected socket currently opened. * * \param address: it contains the address that will be returned by the function. This buffer * must be properly allocated by the user. The address can be either literal or numeric depending * on the value of 'Flags'. * * \param addrlen: the length of the 'address' buffer. * * \param port: it contains the port that will be returned by the function. This buffer * must be properly allocated by the user. * * \param portlen: the length of the 'port' buffer. * * \param flags: a set of flags (the ones defined into the getnameinfo() standard socket function) * that determine if the resulting address must be in numeric / literal form, and so on. * * \param errbuf: a pointer to an user-allocated buffer that will contain the complete * error message. This buffer has to be at least 'errbuflen' in length. * It can be NULL; in this case the error cannot be printed. * * \param errbuflen: length of the buffer that will contains the error. The error message cannot be * larger than 'errbuflen - 1' because the last char is reserved for the string terminator. * * \return It returns '-1' if this function succeeds, '0' otherwise. * The address and port corresponding are returned back in the buffers 'address' and 'port'. * In any case, the returned strings are '0' terminated. * * \warning If the socket is using a connectionless protocol, the address may not be available * until I/O occurs on the socket. */ int sock_getmyinfo(PCAP_SOCKET sock, char *address, int addrlen, char *port, int portlen, int flags, char *errbuf, int errbuflen) { struct sockaddr_storage mysockaddr; socklen_t sockaddrlen; sockaddrlen = sizeof(struct sockaddr_storage); if (getsockname(sock, (struct sockaddr *) &mysockaddr, &sockaddrlen) == -1) { sock_geterrmsg(errbuf, errbuflen, "getsockname() failed"); return 0; } /* Returns the numeric address of the host that triggered the error */ return sock_getascii_addrport(&mysockaddr, address, addrlen, port, portlen, flags, errbuf, errbuflen); } /* * \brief It retrieves two strings containing the address and the port of a given 'sockaddr' variable. * * This function is basically an extended version of the inet_ntop(), which does not exist in * Winsock because the same result can be obtained by using the getnameinfo(). * However, differently from inet_ntop(), this function is able to return also literal names * (e.g. 'localhost') dependently from the 'Flags' parameter. * * The function accepts a sockaddr_storage variable (which can be returned by several functions * like bind(), connect(), accept(), and more) and it transforms its content into a 'human' * form. So, for instance, it is able to translate an hex address (stored in binary form) into * a standard IPv6 address like "::1". * * The behavior of this function depends on the parameters we have in the 'Flags' variable, which * are the ones allowed in the standard getnameinfo() socket function. * * \param sockaddr: a 'sockaddr_in' or 'sockaddr_in6' structure containing the address that * need to be translated from network form into the presentation form. This structure must be * zero-ed prior using it, and the address family field must be filled with the proper value. * The user must cast any 'sockaddr_in' or 'sockaddr_in6' structures to 'sockaddr_storage' before * calling this function. * * \param address: it contains the address that will be returned by the function. This buffer * must be properly allocated by the user. The address can be either literal or numeric depending * on the value of 'Flags'. * * \param addrlen: the length of the 'address' buffer. * * \param port: it contains the port that will be returned by the function. This buffer * must be properly allocated by the user. * * \param portlen: the length of the 'port' buffer. * * \param flags: a set of flags (the ones defined into the getnameinfo() standard socket function) * that determine if the resulting address must be in numeric / literal form, and so on. * * \param errbuf: a pointer to an user-allocated buffer that will contain the complete * error message. This buffer has to be at least 'errbuflen' in length. * It can be NULL; in this case the error cannot be printed. * * \param errbuflen: length of the buffer that will contains the error. The error message cannot be * larger than 'errbuflen - 1' because the last char is reserved for the string terminator. * * \return It returns '-1' if this function succeeds, '0' otherwise. * The address and port corresponding to the given SockAddr are returned back in the buffers 'address' * and 'port'. * In any case, the returned strings are '0' terminated. */ int sock_getascii_addrport(const struct sockaddr_storage *sockaddr, char *address, int addrlen, char *port, int portlen, int flags, char *errbuf, size_t errbuflen) { socklen_t sockaddrlen; int retval; /* Variable that keeps the return value; */ retval = -1; #ifdef _WIN32 if (sockaddr->ss_family == AF_INET) sockaddrlen = sizeof(struct sockaddr_in); else sockaddrlen = sizeof(struct sockaddr_in6); #else sockaddrlen = sizeof(struct sockaddr_storage); #endif if ((flags & NI_NUMERICHOST) == 0) /* Check that we want literal names */ { if ((sockaddr->ss_family == AF_INET6) && (memcmp(&((const struct sockaddr_in6 *) sockaddr)->sin6_addr, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", sizeof(struct in6_addr)) == 0)) { if (address) pcapint_strlcpy(address, SOCKET_NAME_NULL_DAD, addrlen); return retval; } } if (getnameinfo((const struct sockaddr *) sockaddr, sockaddrlen, address, addrlen, port, portlen, flags) != 0) { /* If the user wants to receive an error message */ if (errbuf) { sock_geterrmsg(errbuf, errbuflen, "getnameinfo() failed"); errbuf[errbuflen - 1] = 0; } if (address) { pcapint_strlcpy(address, SOCKET_NO_NAME_AVAILABLE, addrlen); address[addrlen - 1] = 0; } if (port) { pcapint_strlcpy(port, SOCKET_NO_PORT_AVAILABLE, portlen); port[portlen - 1] = 0; } retval = 0; } return retval; } /* * \brief It translates an address from the 'presentation' form into the 'network' form. * * This function basically replaces inet_pton(), which does not exist in Winsock because * the same result can be obtained by using the getaddrinfo(). * An additional advantage is that 'Address' can be both a numeric address (e.g. '127.0.0.1', * like in inet_pton() ) and a literal name (e.g. 'localhost'). * * This function does the reverse job of sock_getascii_addrport(). * * \param address: a zero-terminated string which contains the name you have to * translate. The name can be either literal (e.g. 'localhost') or numeric (e.g. '::1'). * * \param sockaddr: a user-allocated sockaddr_storage structure which will contains the * 'network' form of the requested address. * * \param addr_family: a constant which can assume the following values: * - 'AF_INET' if we want to ping an IPv4 host * - 'AF_INET6' if we want to ping an IPv6 host * - 'AF_UNSPEC' if we do not have preferences about the protocol used to ping the host * * \param errbuf: a pointer to an user-allocated buffer that will contain the complete * error message. This buffer has to be at least 'errbuflen' in length. * It can be NULL; in this case the error cannot be printed. * * \param errbuflen: length of the buffer that will contains the error. The error message cannot be * larger than 'errbuflen - 1' because the last char is reserved for the string terminator. * * \return '-1' if the translation succeeded, '-2' if there was some non critical error, '0' * otherwise. In case it fails, the content of the SockAddr variable remains unchanged. * A 'non critical error' can occur in case the 'Address' is a literal name, which can be mapped * to several network addresses (e.g. 'foo.bar.com' => '10.2.2.2' and '10.2.2.3'). In this case * the content of the SockAddr parameter will be the address corresponding to the first mapping. * * \warning The sockaddr_storage structure MUST be allocated by the user. */ int sock_present2network(const char *address, struct sockaddr_storage *sockaddr, int addr_family, char *errbuf, int errbuflen) { struct addrinfo *addrinfo; struct addrinfo hints; memset(&hints, 0, sizeof(hints)); hints.ai_family = addr_family; addrinfo = sock_initaddress(address, "22222" /* fake port */, &hints, errbuf, errbuflen); if (addrinfo == NULL) return 0; if (addrinfo->ai_family == PF_INET) memcpy(sockaddr, addrinfo->ai_addr, sizeof(struct sockaddr_in)); else memcpy(sockaddr, addrinfo->ai_addr, sizeof(struct sockaddr_in6)); if (addrinfo->ai_next != NULL) { freeaddrinfo(addrinfo); if (errbuf) snprintf(errbuf, errbuflen, "More than one socket requested; using the first one returned"); return -2; } freeaddrinfo(addrinfo); return -1; }