/* * Server-side request handling * * Copyright (C) 1998 Alexandre Julliard * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA */ #include "config.h" #include "wine/port.h" #include <assert.h> #include <errno.h> #include <fcntl.h> #ifdef HAVE_PWD_H #include <pwd.h> #endif #include <signal.h> #include <stdio.h> #include <stdlib.h> #include <stdarg.h> #include <string.h> #include <sys/stat.h> #include <sys/time.h> #include <sys/types.h> #ifdef HAVE_SYS_SOCKET_H # include <sys/socket.h> #endif #ifdef HAVE_SYS_WAIT_H # include <sys/wait.h> #endif #ifdef HAVE_SYS_UIO_H #include <sys/uio.h> #endif #ifdef HAVE_SYS_UN_H #include <sys/un.h> #endif #include <unistd.h> #ifdef HAVE_POLL_H #include <poll.h> #endif #include "ntstatus.h" #define WIN32_NO_STATUS #include "windef.h" #include "winbase.h" #include "wincon.h" #include "winternl.h" #include "wine/library.h" #include "file.h" #include "process.h" #define WANT_REQUEST_HANDLERS #include "request.h" /* Some versions of glibc don't define this */ #ifndef SCM_RIGHTS #define SCM_RIGHTS 1 #endif /* path names for server master Unix socket */ static const char * const server_socket_name = "socket"; /* name of the socket file */ static const char * const server_lock_name = "lock"; /* name of the server lock file */ struct master_socket { struct object obj; /* object header */ struct fd *fd; /* file descriptor of the master socket */ }; static void master_socket_dump( struct object *obj, int verbose ); static void master_socket_destroy( struct object *obj ); static void master_socket_poll_event( struct fd *fd, int event ); static const struct object_ops master_socket_ops = { sizeof(struct master_socket), /* size */ master_socket_dump, /* dump */ no_get_type, /* get_type */ no_add_queue, /* add_queue */ NULL, /* remove_queue */ NULL, /* signaled */ NULL, /* satisfied */ no_signal, /* signal */ no_get_fd, /* get_fd */ no_map_access, /* map_access */ default_get_sd, /* get_sd */ default_set_sd, /* set_sd */ no_lookup_name, /* lookup_name */ no_open_file, /* open_file */ no_close_handle, /* close_handle */ master_socket_destroy /* destroy */ }; static const struct fd_ops master_socket_fd_ops = { NULL, /* get_poll_events */ master_socket_poll_event, /* poll_event */ NULL, /* flush */ NULL, /* get_fd_type */ NULL, /* ioctl */ NULL, /* queue_async */ NULL, /* reselect_async */ NULL /* cancel_async */ }; struct thread *current = NULL; /* thread handling the current request */ unsigned int global_error = 0; /* global error code for when no thread is current */ timeout_t server_start_time = 0; /* server startup time */ int server_dir_fd = -1; /* file descriptor for the server dir */ int config_dir_fd = -1; /* file descriptor for the config dir */ static struct master_socket *master_socket; /* the master socket object */ static struct timeout_user *master_timeout; /* complain about a protocol error and terminate the client connection */ void fatal_protocol_error( struct thread *thread, const char *err, ... ) { va_list args; va_start( args, err ); fprintf( stderr, "Protocol error:%04x: ", thread->id ); vfprintf( stderr, err, args ); va_end( args ); thread->exit_code = 1; kill_thread( thread, 1 ); } /* complain about a protocol error and terminate the client connection */ void fatal_protocol_perror( struct thread *thread, const char *err, ... ) { va_list args; va_start( args, err ); fprintf( stderr, "Protocol error:%04x: ", thread->id ); vfprintf( stderr, err, args ); perror( " " ); va_end( args ); thread->exit_code = 1; kill_thread( thread, 1 ); } /* die on a fatal error */ void fatal_error( const char *err, ... ) { va_list args; va_start( args, err ); fprintf( stderr, "wineserver: " ); vfprintf( stderr, err, args ); va_end( args ); exit(1); } /* die on a fatal error */ void fatal_perror( const char *err, ... ) { va_list args; va_start( args, err ); fprintf( stderr, "wineserver: " ); vfprintf( stderr, err, args ); perror( " " ); va_end( args ); exit(1); } /* allocate the reply data */ void *set_reply_data_size( data_size_t size ) { assert( size <= get_reply_max_size() ); if (size && !(current->reply_data = mem_alloc( size ))) size = 0; current->reply_size = size; return current->reply_data; } /* write the remaining part of the reply */ void write_reply( struct thread *thread ) { int ret; if ((ret = write( get_unix_fd( thread->reply_fd ), (char *)thread->reply_data + thread->reply_size - thread->reply_towrite, thread->reply_towrite )) >= 0) { if (!(thread->reply_towrite -= ret)) { free( thread->reply_data ); thread->reply_data = NULL; /* sent everything, can go back to waiting for requests */ set_fd_events( thread->request_fd, POLLIN ); set_fd_events( thread->reply_fd, 0 ); } return; } if (errno == EPIPE) kill_thread( thread, 0 ); /* normal death */ else if (errno != EWOULDBLOCK && errno != EAGAIN) fatal_protocol_perror( thread, "reply write" ); } /* send a reply to the current thread */ static void send_reply( union generic_reply *reply ) { int ret; if (!current->reply_size) { if ((ret = write( get_unix_fd( current->reply_fd ), reply, sizeof(*reply) )) != sizeof(*reply)) goto error; } else { struct iovec vec[2]; vec[0].iov_base = (void *)reply; vec[0].iov_len = sizeof(*reply); vec[1].iov_base = current->reply_data; vec[1].iov_len = current->reply_size; if ((ret = writev( get_unix_fd( current->reply_fd ), vec, 2 )) < sizeof(*reply)) goto error; if ((current->reply_towrite = current->reply_size - (ret - sizeof(*reply)))) { /* couldn't write it all, wait for POLLOUT */ set_fd_events( current->reply_fd, POLLOUT ); set_fd_events( current->request_fd, 0 ); return; } } free( current->reply_data ); current->reply_data = NULL; return; error: if (ret >= 0) fatal_protocol_error( current, "partial write %d\n", ret ); else if (errno == EPIPE) kill_thread( current, 0 ); /* normal death */ else fatal_protocol_perror( current, "reply write" ); } /* call a request handler */ static void call_req_handler( struct thread *thread ) { union generic_reply reply; enum request req = thread->req.request_header.req; current = thread; current->reply_size = 0; clear_error(); memset( &reply, 0, sizeof(reply) ); if (debug_level) trace_request(); if (req < REQ_NB_REQUESTS) req_handlers[req]( ¤t->req, &reply ); else set_error( STATUS_NOT_IMPLEMENTED ); if (current) { if (current->reply_fd) { reply.reply_header.error = current->error; reply.reply_header.reply_size = current->reply_size; if (debug_level) trace_reply( req, &reply ); send_reply( &reply ); } else { current->exit_code = 1; kill_thread( current, 1 ); /* no way to continue without reply fd */ } } current = NULL; } /* read a request from a thread */ void read_request( struct thread *thread ) { int ret; if (!thread->req_toread) /* no pending request */ { if ((ret = read( get_unix_fd( thread->request_fd ), &thread->req, sizeof(thread->req) )) != sizeof(thread->req)) goto error; if (!(thread->req_toread = thread->req.request_header.request_size)) { /* no data, handle request at once */ call_req_handler( thread ); return; } if (!(thread->req_data = malloc( thread->req_toread ))) { fatal_protocol_error( thread, "no memory for %u bytes request %d\n", thread->req_toread, thread->req.request_header.req ); return; } } /* read the variable sized data */ for (;;) { ret = read( get_unix_fd( thread->request_fd ), (char *)thread->req_data + thread->req.request_header.request_size - thread->req_toread, thread->req_toread ); if (ret <= 0) break; if (!(thread->req_toread -= ret)) { call_req_handler( thread ); free( thread->req_data ); thread->req_data = NULL; return; } } error: if (!ret) /* closed pipe */ kill_thread( thread, 0 ); else if (ret > 0) fatal_protocol_error( thread, "partial read %d\n", ret ); else if (errno != EWOULDBLOCK && errno != EAGAIN) fatal_protocol_perror( thread, "read" ); } /* receive a file descriptor on the process socket */ int receive_fd( struct process *process ) { struct iovec vec; struct send_fd data; struct msghdr msghdr; int fd = -1, ret; #ifdef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS msghdr.msg_accrightslen = sizeof(int); msghdr.msg_accrights = (void *)&fd; #else /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */ char cmsg_buffer[256]; msghdr.msg_control = cmsg_buffer; msghdr.msg_controllen = sizeof(cmsg_buffer); msghdr.msg_flags = 0; #endif /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */ msghdr.msg_name = NULL; msghdr.msg_namelen = 0; msghdr.msg_iov = &vec; msghdr.msg_iovlen = 1; vec.iov_base = (void *)&data; vec.iov_len = sizeof(data); ret = recvmsg( get_unix_fd( process->msg_fd ), &msghdr, 0 ); #ifndef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS if (ret > 0) { struct cmsghdr *cmsg; for (cmsg = CMSG_FIRSTHDR( &msghdr ); cmsg; cmsg = CMSG_NXTHDR( &msghdr, cmsg )) { if (cmsg->cmsg_level != SOL_SOCKET) continue; if (cmsg->cmsg_type == SCM_RIGHTS) fd = *(int *)CMSG_DATA(cmsg); } } #endif /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */ if (ret == sizeof(data)) { struct thread *thread; if (data.tid) thread = get_thread_from_id( data.tid ); else thread = (struct thread *)grab_object( get_process_first_thread( process )); if (!thread || thread->process != process || thread->state == TERMINATED) { if (debug_level) fprintf( stderr, "%04x: *fd* %d <- %d bad thread id\n", data.tid, data.fd, fd ); close( fd ); } else { if (debug_level) fprintf( stderr, "%04x: *fd* %d <- %d\n", thread->id, data.fd, fd ); thread_add_inflight_fd( thread, data.fd, fd ); } if (thread) release_object( thread ); return 0; } if (!ret) { kill_process( process, 0 ); } else if (ret > 0) { fprintf( stderr, "Protocol error: process %04x: partial recvmsg %d for fd\n", process->id, ret ); if (fd != -1) close( fd ); kill_process( process, 1 ); } else { if (errno != EWOULDBLOCK && errno != EAGAIN) { fprintf( stderr, "Protocol error: process %04x: ", process->id ); perror( "recvmsg" ); kill_process( process, 1 ); } } return -1; } /* send an fd to a client */ int send_client_fd( struct process *process, int fd, obj_handle_t handle ) { struct iovec vec; struct msghdr msghdr; int ret; #ifdef HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS msghdr.msg_accrightslen = sizeof(fd); msghdr.msg_accrights = (void *)&fd; #else /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */ char cmsg_buffer[256]; struct cmsghdr *cmsg; msghdr.msg_control = cmsg_buffer; msghdr.msg_controllen = sizeof(cmsg_buffer); msghdr.msg_flags = 0; cmsg = CMSG_FIRSTHDR( &msghdr ); cmsg->cmsg_len = CMSG_LEN( sizeof(fd) ); cmsg->cmsg_level = SOL_SOCKET; cmsg->cmsg_type = SCM_RIGHTS; *(int *)CMSG_DATA(cmsg) = fd; msghdr.msg_controllen = cmsg->cmsg_len; #endif /* HAVE_STRUCT_MSGHDR_MSG_ACCRIGHTS */ msghdr.msg_name = NULL; msghdr.msg_namelen = 0; msghdr.msg_iov = &vec; msghdr.msg_iovlen = 1; vec.iov_base = (void *)&handle; vec.iov_len = sizeof(handle); if (debug_level) fprintf( stderr, "%04x: *fd* %04x -> %d\n", current ? current->id : process->id, handle, fd ); ret = sendmsg( get_unix_fd( process->msg_fd ), &msghdr, 0 ); if (ret == sizeof(handle)) return 0; if (ret >= 0) { fprintf( stderr, "Protocol error: process %04x: partial sendmsg %d\n", process->id, ret ); kill_process( process, 1 ); } else if (errno == EPIPE) { kill_process( process, 0 ); } else { fprintf( stderr, "Protocol error: process %04x: ", process->id ); perror( "sendmsg" ); kill_process( process, 1 ); } return -1; } /* get current tick count to return to client */ unsigned int get_tick_count(void) { return (current_time - server_start_time) / 10000; } static void master_socket_dump( struct object *obj, int verbose ) { struct master_socket *sock = (struct master_socket *)obj; assert( obj->ops == &master_socket_ops ); fprintf( stderr, "Master socket fd=%p\n", sock->fd ); } static void master_socket_destroy( struct object *obj ) { struct master_socket *sock = (struct master_socket *)obj; assert( obj->ops == &master_socket_ops ); release_object( sock->fd ); } /* handle a socket event */ static void master_socket_poll_event( struct fd *fd, int event ) { struct master_socket *sock = get_fd_user( fd ); assert( master_socket->obj.ops == &master_socket_ops ); assert( sock == master_socket ); /* there is only one master socket */ if (event & (POLLERR | POLLHUP)) { /* this is not supposed to happen */ fprintf( stderr, "wineserver: Error on master socket\n" ); set_fd_events( sock->fd, -1 ); } else if (event & POLLIN) { struct sockaddr_un dummy; unsigned int len = sizeof(dummy); int client = accept( get_unix_fd( master_socket->fd ), (struct sockaddr *) &dummy, &len ); if (client == -1) return; fcntl( client, F_SETFL, O_NONBLOCK ); create_process( client, NULL, 0 ); } } /* remove the socket upon exit */ static void socket_cleanup(void) { static int do_it_once; if (!do_it_once++) unlink( server_socket_name ); } /* create a directory and check its permissions */ static void create_dir( const char *name, struct stat *st ) { if (lstat( name, st ) == -1) { if (errno != ENOENT) fatal_perror( "lstat %s", name ); if (mkdir( name, 0700 ) == -1 && errno != EEXIST) fatal_perror( "mkdir %s", name ); if (lstat( name, st ) == -1) fatal_perror( "lstat %s", name ); } if (!S_ISDIR(st->st_mode)) fatal_error( "%s is not a directory\n", name ); if (st->st_uid != getuid()) fatal_error( "%s is not owned by you\n", name ); if (st->st_mode & 077) fatal_error( "%s must not be accessible by other users\n", name ); } /* create the server directory and chdir to it */ static void create_server_dir( const char *dir ) { char *p, *server_dir; struct stat st, st2; if (!(server_dir = strdup( dir ))) fatal_error( "out of memory\n" ); /* first create the base directory if needed */ p = strrchr( server_dir, '/' ); *p = 0; create_dir( server_dir, &st ); /* now create the server directory */ *p = '/'; create_dir( server_dir, &st ); if (chdir( server_dir ) == -1) fatal_perror( "chdir %s", server_dir ); if ((server_dir_fd = open( ".", O_RDONLY )) == -1) fatal_perror( "open %s", server_dir ); if (fstat( server_dir_fd, &st2 ) == -1) fatal_perror( "stat %s", server_dir ); if (st.st_dev != st2.st_dev || st.st_ino != st2.st_ino) fatal_error( "chdir did not end up in %s\n", server_dir ); free( server_dir ); } /* create the lock file and return its file descriptor */ static int create_server_lock(void) { struct stat st; int fd; if (lstat( server_lock_name, &st ) == -1) { if (errno != ENOENT) fatal_perror( "lstat %s/%s", wine_get_server_dir(), server_lock_name ); } else { if (!S_ISREG(st.st_mode)) fatal_error( "%s/%s is not a regular file\n", wine_get_server_dir(), server_lock_name ); } if ((fd = open( server_lock_name, O_CREAT|O_TRUNC|O_WRONLY, 0600 )) == -1) fatal_perror( "error creating %s/%s", wine_get_server_dir(), server_lock_name ); return fd; } /* wait for the server lock */ int wait_for_lock(void) { const char *server_dir = wine_get_server_dir(); int fd, r; struct flock fl; if (!server_dir) return 0; /* no server dir, so no lock to wait on */ create_server_dir( server_dir ); fd = create_server_lock(); fl.l_type = F_WRLCK; fl.l_whence = SEEK_SET; fl.l_start = 0; fl.l_len = 1; r = fcntl( fd, F_SETLKW, &fl ); close(fd); return r; } /* kill the wine server holding the lock */ int kill_lock_owner( int sig ) { const char *server_dir = wine_get_server_dir(); int fd, i, ret = 0; pid_t pid = 0; struct flock fl; if (!server_dir) return 0; /* no server dir, nothing to do */ create_server_dir( server_dir ); fd = create_server_lock(); for (i = 1; i <= 20; i++) { fl.l_type = F_WRLCK; fl.l_whence = SEEK_SET; fl.l_start = 0; fl.l_len = 1; if (fcntl( fd, F_GETLK, &fl ) == -1) goto done; if (fl.l_type != F_WRLCK) goto done; /* the file is not locked */ if (!pid) /* first time around */ { if (!(pid = fl.l_pid)) goto done; /* shouldn't happen */ if (sig == -1) { if (kill( pid, SIGINT ) == -1) goto done; kill( pid, SIGCONT ); ret = 1; } else /* just send the specified signal and return */ { ret = (kill( pid, sig ) != -1); goto done; } } else if (fl.l_pid != pid) goto done; /* no longer the same process */ usleep( 50000 * i ); } /* waited long enough, now kill it */ kill( pid, SIGKILL ); done: close( fd ); return ret; } /* acquire the main server lock */ static void acquire_lock(void) { struct sockaddr_un addr; struct stat st; struct flock fl; int fd, slen, got_lock = 0; fd = create_server_lock(); fl.l_type = F_WRLCK; fl.l_whence = SEEK_SET; fl.l_start = 0; fl.l_len = 1; if (fcntl( fd, F_SETLK, &fl ) != -1) { /* check for crashed server */ if (stat( server_socket_name, &st ) != -1 && /* there is a leftover socket */ stat( "core", &st ) != -1 && st.st_size) /* and there is a non-empty core file */ { fprintf( stderr, "Warning: a previous instance of the wine server seems to have crashed.\n" "Please run 'gdb %s %s/core',\n" "type 'backtrace' at the gdb prompt and report the results. Thanks.\n\n", server_argv0, wine_get_server_dir() ); } unlink( server_socket_name ); /* we got the lock, we can safely remove the socket */ got_lock = 1; /* in that case we reuse fd without closing it, this ensures * that we hold the lock until the process exits */ } else { switch(errno) { case ENOLCK: break; case EACCES: /* check whether locks work at all on this file system */ if (fcntl( fd, F_GETLK, &fl ) == -1) break; /* fall through */ case EAGAIN: exit(2); /* we didn't get the lock, exit with special status */ default: fatal_perror( "fcntl %s/%s", wine_get_server_dir(), server_lock_name ); } /* it seems we can't use locks on this fs, so we will use the socket existence as lock */ close( fd ); } if ((fd = socket( AF_UNIX, SOCK_STREAM, 0 )) == -1) fatal_perror( "socket" ); addr.sun_family = AF_UNIX; strcpy( addr.sun_path, server_socket_name ); slen = sizeof(addr) - sizeof(addr.sun_path) + strlen(addr.sun_path) + 1; #ifdef HAVE_STRUCT_SOCKADDR_UN_SUN_LEN addr.sun_len = slen; #endif if (bind( fd, (struct sockaddr *)&addr, slen ) == -1) { if ((errno == EEXIST) || (errno == EADDRINUSE)) { if (got_lock) fatal_error( "couldn't bind to the socket even though we hold the lock\n" ); exit(2); /* we didn't get the lock, exit with special status */ } fatal_perror( "bind" ); } atexit( socket_cleanup ); chmod( server_socket_name, 0600 ); /* make sure no other user can connect */ if (listen( fd, 5 ) == -1) fatal_perror( "listen" ); if (!(master_socket = alloc_object( &master_socket_ops )) || !(master_socket->fd = create_anonymous_fd( &master_socket_fd_ops, fd, &master_socket->obj, 0 ))) fatal_error( "out of memory\n" ); set_fd_events( master_socket->fd, POLLIN ); make_object_static( &master_socket->obj ); } /* open the master server socket and start waiting for new clients */ void open_master_socket(void) { const char *server_dir = wine_get_server_dir(); const char *config_dir = wine_get_config_dir(); int fd, pid, status, sync_pipe[2]; char dummy; /* make sure no request is larger than the maximum size */ assert( sizeof(union generic_request) == sizeof(struct request_max_size) ); assert( sizeof(union generic_reply) == sizeof(struct request_max_size) ); /* make sure the stdio fds are open */ fd = open( "/dev/null", O_RDWR ); while (fd >= 0 && fd <= 2) fd = dup( fd ); if (!server_dir) fatal_error( "directory %s cannot be accessed\n", config_dir ); if (chdir( config_dir ) == -1) fatal_perror( "chdir to %s", config_dir ); if ((config_dir_fd = open( ".", O_RDONLY )) == -1) fatal_perror( "open %s", config_dir ); create_server_dir( server_dir ); if (!foreground) { if (pipe( sync_pipe ) == -1) fatal_perror( "pipe" ); pid = fork(); switch( pid ) { case 0: /* child */ setsid(); close( sync_pipe[0] ); acquire_lock(); /* close stdin and stdout */ dup2( fd, 0 ); dup2( fd, 1 ); /* signal parent */ dummy = 0; write( sync_pipe[1], &dummy, 1 ); close( sync_pipe[1] ); break; case -1: fatal_perror( "fork" ); break; default: /* parent */ close( sync_pipe[1] ); /* wait for child to signal us and then exit */ if (read( sync_pipe[0], &dummy, 1 ) == 1) _exit(0); /* child terminated, propagate exit status */ waitpid( pid, &status, 0 ); if (WIFEXITED(status)) _exit( WEXITSTATUS(status) ); _exit(1); } } else /* remain in the foreground */ { acquire_lock(); } /* init the process tracing mechanism */ init_tracing_mechanism(); close( fd ); } /* master socket timer expiration handler */ static void close_socket_timeout( void *arg ) { master_timeout = NULL; flush_registry(); if (debug_level) fprintf( stderr, "wineserver: exiting (pid=%ld)\n", (long) getpid() ); #ifdef DEBUG_OBJECTS close_objects(); /* shut down everything properly */ #endif exit( 0 ); } /* close the master socket and stop waiting for new clients */ void close_master_socket( timeout_t timeout ) { if (master_socket) { release_object( master_socket ); master_socket = NULL; } if (master_timeout) /* cancel previous timeout */ remove_timeout_user( master_timeout ); master_timeout = add_timeout_user( timeout, close_socket_timeout, NULL ); }