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- /* Copyright 2003-2004 Roger Dingledine; Copyright 2004 Nick Mathewson */
- /* See LICENSE for licensing information */
- /* $Id$ */
- /* This is required on rh7 to make strptime not complain.
- */
- #define _GNU_SOURCE
- #include "orconfig.h"
- #include "compat.h"
- #ifdef MS_WINDOWS
- #include <process.h>
- #endif
- #ifdef HAVE_UNAME
- #include <sys/utsname.h>
- #endif
- #ifdef HAVE_SYS_TIME_H
- #include <sys/time.h>
- #endif
- #ifdef HAVE_UNISTD_H
- #include <unistd.h>
- #endif
- #ifdef HAVE_SYS_FCNTL_H
- #include <sys/fcntl.h>
- #endif
- #ifdef HAVE_PWD_H
- #include <pwd.h>
- #endif
- #ifdef HAVE_GRP_H
- #include <grp.h>
- #endif
- #ifdef HAVE_FCNTL_H
- #include <fcntl.h>
- #endif
- #ifdef HAVE_SYS_RESOURCE_H
- #include <sys/resource.h>
- #endif
- #ifdef HAVE_ERRNO_H
- #include <errno.h>
- #endif
- #ifdef HAVE_NETINET_IN_H
- #include <netinet/in.h>
- #endif
- #ifdef HAVE_ARPA_INET_H
- #include <arpa/inet.h>
- #endif
- #ifndef HAVE_GETTIMEOFDAY
- #ifdef HAVE_FTIME
- #include <sys/timeb.h>
- #endif
- #endif
- #ifdef HAVE_SYS_SOCKET_H
- #include <sys/socket.h>
- #endif
- #ifdef HAVE_SYS_PARAM_H
- #include <sys/param.h> /* FreeBSD needs this to know what version it is */
- #endif
- #include <stdarg.h>
- #include <stdio.h>
- #include <stdlib.h>
- #include <string.h>
- #include <assert.h>
- #include "log.h"
- #include "util.h"
- /* Inline the strl functions if the platform doesn't have them. */
- #ifndef HAVE_STRLCPY
- #include "strlcpy.c"
- #endif
- #ifndef HAVE_STRLCAT
- #include "strlcat.c"
- #endif
- /** Replacement for snprintf. Differs from platform snprintf in two
- * ways: First, always NUL-terminates its output. Second, always
- * returns -1 if the result is truncated. (Note that this return
- * behavior does <i>not</i> conform to C99; it just happens to be the
- * easiest to emulate "return -1" with conformant implementations than
- * it is to emulate "return number that would be written" with
- * non-conformant implementations.) */
- int tor_snprintf(char *str, size_t size, const char *format, ...)
- {
- va_list ap;
- int r;
- va_start(ap,format);
- r = tor_vsnprintf(str,size,format,ap);
- va_end(ap);
- return r;
- }
- /** Replacement for vsnpritnf; behavior differs as tor_snprintf differs from
- * snprintf.
- */
- int tor_vsnprintf(char *str, size_t size, const char *format, va_list args)
- {
- int r;
- #ifdef MS_WINDOWS
- r = _vsnprintf(str, size, format, args);
- #else
- r = vsnprintf(str, size, format, args);
- #endif
- str[size-1] = '\0';
- if (r < 0 || ((size_t)r) >= size)
- return -1;
- return r;
- }
- #ifndef UNALIGNED_INT_ACCESS_OK
- /**
- * Read a 16-bit value beginning at <b>cp</b>. Equaivalent to
- * *(uint16_t*)(cp), but will not cause segfaults on platforms that forbid
- * unaligned memory access.
- */
- uint16_t get_uint16(const char *cp)
- {
- uint16_t v;
- memcpy(&v,cp,2);
- return v;
- }
- /**
- * Read a 32-bit value beginning at <b>cp</b>. Equaivalent to
- * *(uint32_t*)(cp), but will not cause segfaults on platforms that forbid
- * unaligned memory access.
- */
- uint32_t get_uint32(const char *cp)
- {
- uint32_t v;
- memcpy(&v,cp,4);
- return v;
- }
- /**
- * Set a 16-bit value beginning at <b>cp</b> to <b>v</b>. Equivalent to
- * *(uint16_t)(cp) = v, but will not cause segfaults on platforms that forbid
- * unaligned memory access. */
- void set_uint16(char *cp, uint16_t v)
- {
- memcpy(cp,&v,2);
- }
- /**
- * Set a 32-bit value beginning at <b>cp</b> to <b>v</b>. Equivalent to
- * *(uint32_t)(cp) = v, but will not cause segfaults on platforms that forbid
- * unaligned memory access. */
- void set_uint32(char *cp, uint32_t v)
- {
- memcpy(cp,&v,4);
- }
- #endif
- /**
- * Rename the file 'from' to the file 'to'. On unix, this is the same as
- * rename(2). On windows, this removes 'to' first if it already exists.
- * Returns 0 on success. Returns -1 and sets errno on failure.
- */
- int replace_file(const char *from, const char *to)
- {
- #ifndef MS_WINDOWS
- return rename(from,to);
- #else
- switch(file_status(to))
- {
- case FN_NOENT:
- break;
- case FN_FILE:
- if (unlink(to)) return -1;
- break;
- case FN_ERROR:
- return -1;
- case FN_DIR:
- errno = EISDIR;
- return -1;
- }
- return rename(from,to);
- #endif
- }
- /** Turn <b>socket</b> into a nonblocking socket.
- */
- void set_socket_nonblocking(int socket)
- {
- #ifdef MS_WINDOWS
- /* Yes means no and no means yes. Do you not want to be nonblocking? */
- int nonblocking = 0;
- ioctlsocket(socket, FIONBIO, (unsigned long*) &nonblocking);
- #else
- fcntl(socket, F_SETFL, O_NONBLOCK);
- #endif
- }
- /**
- * Allocate a pair of connected sockets. (Like socketpair(family,
- * type,protocol,fd), but works on systems that don't have
- * socketpair.)
- *
- * Currently, only (AF_UNIX, SOCK_STREAM, 0 ) sockets are supported.
- *
- * Note that on systems without socketpair, this call will fail if
- * localhost is inaccessible (for example, if the networking
- * stack is down). And even if it succeeds, the socket pair will not
- * be able to read while localhost is down later (the socket pair may
- * even close, depending on OS-specific timeouts).
- **/
- int
- tor_socketpair(int family, int type, int protocol, int fd[2])
- {
- #ifdef HAVE_SOCKETPAIR
- return socketpair(family, type, protocol, fd);
- #else
- /* This socketpair does not work when localhost is down. So
- * it's really not the same thing at all. But it's close enough
- * for now, and really, when localhost is down sometimes, we
- * have other problems too.
- */
- int listener = -1;
- int connector = -1;
- int acceptor = -1;
- struct sockaddr_in listen_addr;
- struct sockaddr_in connect_addr;
- int size;
- if (protocol
- #ifdef AF_UNIX
- || family != AF_UNIX
- #endif
- ) {
- #ifdef MS_WINDOWS
- errno = WSAEAFNOSUPPORT;
- #else
- errno = EAFNOSUPPORT;
- #endif
- return -1;
- }
- if (!fd) {
- errno = EINVAL;
- return -1;
- }
- listener = socket(AF_INET, type, 0);
- if (listener == -1)
- return -1;
- memset (&listen_addr, 0, sizeof (listen_addr));
- listen_addr.sin_family = AF_INET;
- listen_addr.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
- listen_addr.sin_port = 0; /* kernel choses port. */
- if (bind(listener, (struct sockaddr *) &listen_addr, sizeof (listen_addr))
- == -1)
- goto tidy_up_and_fail;
- if (listen(listener, 1) == -1)
- goto tidy_up_and_fail;
- connector = socket(AF_INET, type, 0);
- if (connector == -1)
- goto tidy_up_and_fail;
- /* We want to find out the port number to connect to. */
- size = sizeof (connect_addr);
- if (getsockname(listener, (struct sockaddr *) &connect_addr, &size) == -1)
- goto tidy_up_and_fail;
- if (size != sizeof (connect_addr))
- goto abort_tidy_up_and_fail;
- if (connect(connector, (struct sockaddr *) &connect_addr,
- sizeof (connect_addr)) == -1)
- goto tidy_up_and_fail;
- size = sizeof (listen_addr);
- acceptor = accept(listener, (struct sockaddr *) &listen_addr, &size);
- if (acceptor == -1)
- goto tidy_up_and_fail;
- if (size != sizeof(listen_addr))
- goto abort_tidy_up_and_fail;
- tor_close_socket(listener);
- /* Now check we are talking to ourself by matching port and host on the
- two sockets. */
- if (getsockname(connector, (struct sockaddr *) &connect_addr, &size) == -1)
- goto tidy_up_and_fail;
- if (size != sizeof (connect_addr)
- || listen_addr.sin_family != connect_addr.sin_family
- || listen_addr.sin_addr.s_addr != connect_addr.sin_addr.s_addr
- || listen_addr.sin_port != connect_addr.sin_port) {
- goto abort_tidy_up_and_fail;
- }
- fd[0] = connector;
- fd[1] = acceptor;
- return 0;
- abort_tidy_up_and_fail:
- #ifdef MS_WINDOWS
- errno = WSAECONNABORTED;
- #else
- errno = ECONNABORTED; /* I hope this is portable and appropriate. */
- #endif
- tidy_up_and_fail:
- {
- int save_errno = errno;
- if (listener != -1)
- tor_close_socket(listener);
- if (connector != -1)
- tor_close_socket(connector);
- if (acceptor != -1)
- tor_close_socket(acceptor);
- errno = save_errno;
- return -1;
- }
- #endif
- }
- /** Get the maximum allowed number of file descriptors. (Some systems
- * have a low soft limit.) Make sure we set it to at least
- * <b>required_min</b>. Return 0 if we can, or -1 if we fail. */
- int set_max_file_descriptors(unsigned int required_min) {
- #ifndef HAVE_GETRLIMIT
- log_fn(LOG_INFO,"This platform is missing getrlimit(). Proceeding.");
- return 0; /* hope we'll be ok */
- #else
- struct rlimit rlim;
- if (getrlimit(RLIMIT_NOFILE, &rlim) != 0) {
- log_fn(LOG_WARN, "Could not get maximum number of file descriptors: %s",
- strerror(errno));
- return -1;
- }
- if(required_min > rlim.rlim_max) {
- log_fn(LOG_WARN,"We need %d file descriptors available, and we're limited to %d. Please change your ulimit.", required_min, (int)rlim.rlim_max);
- return -1;
- }
- if(required_min > rlim.rlim_cur) {
- log_fn(LOG_INFO,"Raising max file descriptors from %d to %d.",
- (int)rlim.rlim_cur, (int)rlim.rlim_max);
- }
- rlim.rlim_cur = rlim.rlim_max;
- if (setrlimit(RLIMIT_NOFILE, &rlim) != 0) {
- log_fn(LOG_WARN, "Could not set maximum number of file descriptors: %s",
- strerror(errno));
- return -1;
- }
- return 0;
- #endif
- }
- /** Call setuid and setgid to run as <b>user</b>:<b>group</b>. Return 0 on
- * success. On failure, log and return -1.
- */
- int switch_id(char *user, char *group) {
- #ifndef MS_WINDOWS
- struct passwd *pw = NULL;
- struct group *gr = NULL;
- if (user) {
- pw = getpwnam(user);
- if (pw == NULL) {
- log_fn(LOG_ERR,"User '%s' not found.", user);
- return -1;
- }
- }
- /* switch the group first, while we still have the privileges to do so */
- if (group) {
- gr = getgrnam(group);
- if (gr == NULL) {
- log_fn(LOG_ERR,"Group '%s' not found.", group);
- return -1;
- }
- if (setgid(gr->gr_gid) != 0) {
- log_fn(LOG_ERR,"Error setting GID: %s", strerror(errno));
- return -1;
- }
- } else if (user) {
- if (setgid(pw->pw_gid) != 0) {
- log_fn(LOG_ERR,"Error setting GID: %s", strerror(errno));
- return -1;
- }
- }
- /* now that the group is switched, we can switch users and lose
- privileges */
- if (user) {
- if (setuid(pw->pw_uid) != 0) {
- log_fn(LOG_ERR,"Error setting UID: %s", strerror(errno));
- return -1;
- }
- }
- return 0;
- #endif
- log_fn(LOG_ERR,
- "User or group specified, but switching users is not supported.");
- return -1;
- }
- /** Set *addr to the IP address (in dotted-quad notation) stored in c.
- * Return 1 on success, 0 if c is badly formatted. (Like inet_aton(c,addr),
- * but works on Windows and Solaris.)
- */
- int tor_inet_aton(const char *c, struct in_addr* addr)
- {
- #ifdef HAVE_INET_ATON
- return inet_aton(c, addr);
- #else
- uint32_t r;
- tor_assert(c);
- tor_assert(addr);
- if (strcmp(c, "255.255.255.255") == 0) {
- addr->s_addr = 0xFFFFFFFFu;
- return 1;
- }
- r = inet_addr(c);
- if (r == INADDR_NONE)
- return 0;
- addr->s_addr = r;
- return 1;
- #endif
- }
- /* Hold the result of our call to <b>uname</b>. */
- static char uname_result[256];
- /* True iff uname_result is set. */
- static int uname_result_is_set = 0;
- /* Return a pointer to a description of our platform.
- */
- const char *
- get_uname(void)
- {
- #ifdef HAVE_UNAME
- struct utsname u;
- #endif
- if (!uname_result_is_set) {
- #ifdef HAVE_UNAME
- if (uname(&u) != -1) {
- /* (linux says 0 is success, solaris says 1 is success) */
- tor_snprintf(uname_result, sizeof(uname_result), "%s %s %s",
- u.sysname, u.nodename, u.machine);
- } else
- #endif
- {
- strlcpy(uname_result, "Unknown platform", sizeof(uname_result));
- }
- uname_result_is_set = 1;
- }
- return uname_result;
- }
- /*
- * Process control
- */
- /** Minimalist interface to run a void function in the background. On
- * unix calls fork, on win32 calls beginthread. Returns -1 on failure.
- * func should not return, but rather should call spawn_exit.
- */
- int spawn_func(int (*func)(void *), void *data)
- {
- #ifdef MS_WINDOWS
- int rv;
- rv = _beginthread(func, 0, data);
- if (rv == (unsigned long) -1)
- return -1;
- return 0;
- #else
- pid_t pid;
- pid = fork();
- if (pid<0)
- return -1;
- if (pid==0) {
- /* Child */
- func(data);
- tor_assert(0); /* Should never reach here. */
- return 0; /* suppress "control-reaches-end-of-non-void" warning. */
- } else {
- /* Parent */
- return 0;
- }
- #endif
- }
- /** End the current thread/process.
- */
- void spawn_exit()
- {
- #ifdef MS_WINDOWS
- _endthread();
- #else
- exit(0);
- #endif
- }
- /** Set *timeval to the current time of day. On error, log and terminate.
- * (Same as gettimeofday(timeval,NULL), but never returns -1.)
- */
- void tor_gettimeofday(struct timeval *timeval) {
- #ifdef HAVE_GETTIMEOFDAY
- if (gettimeofday(timeval, NULL)) {
- log_fn(LOG_ERR, "gettimeofday failed.");
- /* If gettimeofday dies, we have either given a bad timezone (we didn't),
- or segfaulted.*/
- exit(1);
- }
- #elif defined(HAVE_FTIME)
- struct timeb tb;
- ftime(&tb);
- timeval->tv_sec = tb.time;
- timeval->tv_usec = tb.millitm * 1000;
- #else
- #error "No way to get time."
- #endif
- return;
- }
- #ifndef MS_WINDOWS
- struct tor_mutex_t {
- };
- tor_mutex_t *tor_mutex_new(void) { return NULL; }
- void tor_mutex_acquire(tor_mutex_t *m) { }
- void tor_mutex_release(tor_mutex_t *m) { }
- void tor_mutex_free(tor_mutex_t *m) { }
- #else
- struct tor_mutex_t {
- HANDLE handle;
- };
- tor_mutex_t *tor_mutex_new(void)
- {
- tor_mutex_t *m;
- m = tor_malloc_zero(sizeof(tor_mutex_t));
- m->handle = CreateMutex(NULL, FALSE, NULL);
- tor_assert(m->handle != NULL);
- return m;
- }
- void tor_mutex_free(tor_mutex_t *m)
- {
- CloseHandle(m->handle);
- tor_free(m);
- }
- void tor_mutex_acquire(tor_mutex_t *m)
- {
- DWORD r;
- r = WaitForSingleObject(m->handle, INFINITE);
- switch (r) {
- case WAIT_ABANDONED: /* holding thread exited. */
- case WAIT_OBJECT_0: /* we got the mutex normally. */
- break;
- case WAIT_TIMEOUT: /* Should never happen. */
- tor_assert(0);
- break;
- case WAIT_FAILED:
- log_fn(LOG_WARN, "Failed to acquire mutex: %d", GetLastError());
- }
- }
- void tor_mutex_release(tor_mutex_t *m)
- {
- BOOL r;
- r = ReleaseMutex(m->handle);
- if (!r) {
- log_fn(LOG_WARN, "Failed to release mutex: %d", GetLastError());
- }
- }
- #endif
- /**
- * On Windows, WSAEWOULDBLOCK is not always correct: when you see it,
- * you need to ask the socket for its actual errno. Also, you need to
- * get your errors from WSAGetLastError, not errno. (If you supply a
- * socket of -1, we check WSAGetLastError, but don't correct
- * WSAEWOULDBLOCKs.)
- */
- #ifdef MS_WINDOWS
- int tor_socket_errno(int sock)
- {
- int optval, optvallen=sizeof(optval);
- int err = WSAGetLastError();
- if (err == WSAEWOULDBLOCK && sock >= 0) {
- if (getsockopt(sock, SOL_SOCKET, SO_ERROR, (void*)&optval, &optvallen))
- return err;
- if (optval)
- return optval;
- }
- return err;
- }
- #endif
- #ifdef MS_WINDOWS
- #define E(code, s) { code, (s " [" #code " ]") }
- struct { int code; const char *msg; } windows_socket_errors[] = {
- E(WSAEINTR, "Interrupted function call"),
- E(WSAEACCES, "Permission denied"),
- E(WSAEFAULT, "Bad address"),
- E(WSAEINVAL, "Invalid argument"),
- E(WSAEMFILE, "Too many open files"),
- E(WSAEWOULDBLOCK, "Resource temporarily unavailable"),
- E(WSAEINPROGRESS, "Operation now in progress"),
- E(WSAEALREADY, "Operation already in progress"),
- E(WSAENOTSOCK, "Socket operation on nonsocket"),
- E(WSAEDESTADDRREQ, "Destination address required"),
- E(WSAEMSGSIZE, "Message too long"),
- E(WSAEPROTOTYPE, "Protocol wrong for socket"),
- E(WSAENOPROTOOPT, "Bad protocol option"),
- E(WSAEPROTONOSUPPORT, "Protocol not supported"),
- E(WSAESOCKTNOSUPPORT, "Socket type not supported"),
- /* What's the difference between NOTSUPP and NOSUPPORT? :) */
- E(WSAEOPNOTSUPP, "Operation not supported"),
- E(WSAEPFNOSUPPORT, "Protocol family not supported"),
- E(WSAEAFNOSUPPORT, "Address family not supported by protocol family"),
- E(WSAEADDRINUSE, "Address already in use"),
- E(WSAEADDRNOTAVAIL, "Cannot assign requested address"),
- E(WSAENETDOWN, "Network is down"),
- E(WSAENETUNREACH, "Network is unreachable"),
- E(WSAENETRESET, "Network dropped connection on reset"),
- E(WSAECONNABORTED, "Software caused connection abort"),
- E(WSAECONNRESET, "Connection reset by peer"),
- E(WSAENOBUFS, "No buffer space avaialable"),
- E(WSAEISCONN, "Socket is already connected"),
- E(WSAENOTCONN, "Socket is not connected"),
- E(WSAESHUTDOWN, "Cannot send after socket shutdown"),
- E(WSAETIMEDOUT, "Connection timed out"),
- E(WSAECONNREFUSED, "Connection refused"),
- E(WSAEHOSTDOWN, "Host is down"),
- E(WSAEHOSTUNREACH, "No route to host"),
- E(WSAEPROCLIM, "Too many processes"),
- /* Yes, some of these start with WSA, not WSAE. No, I don't know why. */
- E(WSASYSNOTREADY, "Network subsystem is unavailable"),
- E(WSAVERNOTSUPPORTED, "Winsock.dll out of range"),
- E(WSANOTINITIALISED, "Successful WSAStartup not yet performed"),
- E(WSAEDISCON, "Graceful shutdown now in progress"),
- #ifdef WSATYPE_NOT_FOUND
- E(WSATYPE_NOT_FOUND, "Class type not found"),
- #endif
- E(WSAHOST_NOT_FOUND, "Host not found"),
- E(WSATRY_AGAIN, "Nonauthoritative host not found"),
- E(WSANO_RECOVERY, "This is a nonrecoverable error"),
- E(WSANO_DATA, "Valid name, no data record of requested type)"),
- /* There are some more error codes whose numeric values are marked
- * <b>OS dependent</b>. They start with WSA_, apparently for the same
- * reason that practitioners of some craft traditions deliberately
- * introduce imperfections into their baskets and rugs "to allow the
- * evil spirits to escape." If we catch them, then our binaries
- * might not report consistent results across versions of Windows.
- * Thus, I'm going to let them all fall through.
- */
- { -1, NULL },
- };
- /** There does not seem to be a strerror equivalent for winsock errors.
- * Naturally, we have to roll our own.
- */
- const char *tor_socket_strerror(int e)
- {
- int i;
- for (i=0; windows_socket_errors[i].code >= 0; ++i) {
- if (e == windows_socket_errors[i].code)
- return windows_socket_errors[i].msg;
- }
- return strerror(e);
- }
- #endif
- /*
- Local Variables:
- mode:c
- indent-tabs-mode:nil
- c-basic-offset:2
- End:
- */
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