/* * Copyright (c) 1999 Adrian Sun (asun@zoology.washington.edu) * Copyright (c) 1990,1993 Regents of The University of Michigan. * All Rights Reserved. See COPYRIGHT. * * modified from main.c. this handles afp over tcp. */ #ifdef HAVE_CONFIG_H #include "config.h" #endif /* HAVE_CONFIG_H */ #include #include #include #include #include #ifdef HAVE_UNISTD_H #include #endif /* HAVE_UNISTD_H */ #include #include #ifdef HAVE_SYS_STAT_H #include #endif /* HAVE_SYS_STAT_H */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include "switch.h" #include "auth.h" #include "fork.h" #include "dircache.h" #ifdef FORCE_UIDGID #warning UIDGID #include "uid.h" #endif /* FORCE_UIDGID */ /* * We generally pass this from afp_over_dsi to all afp_* funcs, so it should already be * available everywhere. Unfortunately some funcs (eg acltoownermode) need acces to it * but are deeply nested in the function chain with the caller already without acces to it. * Changing this would require adding a reference to the caller which itself might be * called in many places (eg acltoownermode is called from accessmode). * The only sane way out is providing a copy of it here: */ AFPObj *AFPobj = NULL; typedef struct { uint16_t DSIreqID; uint8_t AFPcommand; uint32_t result; } rc_elem_t; /* * AFP replay cache: * - fix sized array * - indexed just by taking DSIreqID mod REPLAYCACHE_SIZE */ static rc_elem_t replaycache[REPLAYCACHE_SIZE]; static sigjmp_buf recon_jmp; static void afp_dsi_close(AFPObj *obj) { DSI *dsi = obj->handle; close(obj->ipc_fd); obj->ipc_fd = -1; /* we may have been called from a signal handler caught when afpd was running * as uid 0, that's the wrong user for volume's prexec_close scripts if any, * restore our login user */ if (geteuid() != obj->uid) { if (seteuid( obj->uid ) < 0) { LOG(log_error, logtype_afpd, "can't seteuid(%u) back %s: uid: %u, euid: %u", obj->uid, strerror(errno), getuid(), geteuid()); exit(EXITERR_SYS); } } close_all_vol(); if (obj->logout) (*obj->logout)(); LOG(log_note, logtype_afpd, "AFP statistics: %.2f KB read, %.2f KB written", dsi->read_count/1024.0, dsi->write_count/1024.0); log_dircache_stat(); dsi_close(dsi); } /* ------------------------------- * SIGTERM * a little bit of code duplication. */ static void afp_dsi_die(int sig) { DSI *dsi = (DSI *)AFPobj->handle; if (dsi->flags & DSI_RECONINPROG) { /* Primary reconnect succeeded, got SIGTERM from afpd parent */ dsi->flags &= ~DSI_RECONINPROG; return; /* this returns to afp_disconnect */ } if (dsi->flags & DSI_DISCONNECTED) { LOG(log_note, logtype_afpd, "Disconnected session terminating"); exit(0); } dsi_attention(AFPobj->handle, AFPATTN_SHUTDOWN); afp_dsi_close(AFPobj); if (sig) /* if no signal, assume dieing because logins are disabled & don't log it (maintenance mode)*/ LOG(log_info, logtype_afpd, "Connection terminated"); if (sig == SIGTERM || sig == SIGALRM) { exit( 0 ); } else { exit(sig); } } /* SIGQUIT handler */ static void ipc_reconnect_handler(int sig _U_) { DSI *dsi = (DSI *)AFPobj->handle; if (reconnect_ipc(AFPobj) != 0) { LOG(log_error, logtype_afpd, "ipc_reconnect_handler: failed IPC reconnect"); afp_dsi_close(AFPobj); exit(EXITERR_SYS); } if (ipc_child_write(AFPobj->ipc_fd, IPC_GETSESSION, AFPobj->sinfo.clientid_len, AFPobj->sinfo.clientid) != 0) { LOG(log_error, logtype_afpd, "ipc_reconnect_handler: failed IPC ID resend"); afp_dsi_close(AFPobj); exit(EXITERR_SYS); } LOG(log_note, logtype_afpd, "ipc_reconnect_handler: IPC reconnect done"); } /* SIGURG handler (primary reconnect) */ static void afp_dsi_transfer_session(int sig _U_) { uint16_t dsiID; int socket; DSI *dsi = (DSI *)AFPobj->handle; LOG(log_debug, logtype_afpd, "afp_dsi_transfer_session: got SIGURG, trying to receive session"); if (readt(AFPobj->ipc_fd, &dsiID, 2, 0, 2) != 2) { LOG(log_error, logtype_afpd, "afp_dsi_transfer_session: couldn't receive DSI id, goodbye"); afp_dsi_close(AFPobj); exit(EXITERR_SYS); } if ((socket = recv_fd(AFPobj->ipc_fd, 1)) == -1) { LOG(log_error, logtype_afpd, "afp_dsi_transfer_session: couldn't receive session fd, goodbye"); afp_dsi_close(AFPobj); exit(EXITERR_SYS); } LOG(log_debug, logtype_afpd, "afp_dsi_transfer_session: received socket fd: %i", socket); dsi->proto_close(dsi); dsi->socket = socket; dsi->flags = DSI_RECONSOCKET; dsi->datalen = 0; dsi->eof = dsi->start = dsi->buffer; dsi->in_write = 0; dsi->header.dsi_requestID = dsiID; dsi->header.dsi_command = DSIFUNC_CMD; /* * The session transfer happens in the middle of FPDisconnect old session, thus we * have to send the reply now. */ if (!dsi_cmdreply(dsi, AFP_OK)) { LOG(log_error, logtype_afpd, "dsi_cmdreply: %s", strerror(errno) ); afp_dsi_close(AFPobj); exit(EXITERR_CLNT); } LOG(log_note, logtype_afpd, "afp_dsi_transfer_session: succesfull primary reconnect"); /* * Now returning from this signal handler return to dsi_receive which should start * reading/continuing from the connected socket that was passed via the parent from * another session. The parent will terminate that session. */ siglongjmp(recon_jmp, 1); } /* ------------------- */ static void afp_dsi_timedown(int sig _U_) { struct sigaction sv; struct itimerval it; DSI *dsi = (DSI *)AFPobj->handle; dsi->flags |= DSI_DIE; /* shutdown and don't reconnect. server going down in 5 minutes. */ setmessage("The server is going down for maintenance."); if (dsi_attention(AFPobj->handle, AFPATTN_SHUTDOWN | AFPATTN_NORECONNECT | AFPATTN_MESG | AFPATTN_TIME(5)) < 0) { DSI *dsi = (DSI *)AFPobj->handle; dsi->down_request = 1; } it.it_interval.tv_sec = 0; it.it_interval.tv_usec = 0; it.it_value.tv_sec = 300; it.it_value.tv_usec = 0; if ( setitimer( ITIMER_REAL, &it, NULL ) < 0 ) { LOG(log_error, logtype_afpd, "afp_timedown: setitimer: %s", strerror(errno) ); afp_dsi_die(EXITERR_SYS); } memset(&sv, 0, sizeof(sv)); sv.sa_handler = afp_dsi_die; sigemptyset( &sv.sa_mask ); sigaddset(&sv.sa_mask, SIGHUP); sigaddset(&sv.sa_mask, SIGTERM); sv.sa_flags = SA_RESTART; if ( sigaction( SIGALRM, &sv, NULL ) < 0 ) { LOG(log_error, logtype_afpd, "afp_timedown: sigaction: %s", strerror(errno) ); afp_dsi_die(EXITERR_SYS); } /* ignore myself */ sv.sa_handler = SIG_IGN; sigemptyset( &sv.sa_mask ); sv.sa_flags = SA_RESTART; if ( sigaction( SIGUSR1, &sv, NULL ) < 0 ) { LOG(log_error, logtype_afpd, "afp_timedown: sigaction SIGHUP: %s", strerror(errno) ); afp_dsi_die(EXITERR_SYS); } } /* --------------------------------- * SIGHUP reload configuration file */ volatile int reload_request = 0; static void afp_dsi_reload(int sig _U_) { reload_request = 1; } /* --------------------------------- * SIGINT: enable max_debug LOGging */ static volatile sig_atomic_t debug_request = 0; static void afp_dsi_debug(int sig _U_) { debug_request = 1; } /* ---------------------- */ static void afp_dsi_getmesg (int sig _U_) { DSI *dsi = (DSI *)AFPobj->handle; dsi->msg_request = 1; if (dsi_attention(AFPobj->handle, AFPATTN_MESG | AFPATTN_TIME(5)) < 0) dsi->msg_request = 2; } static void alarm_handler(int sig _U_) { int err; DSI *dsi = (DSI *)AFPobj->handle; /* we have to restart the timer because some libraries may use alarm() */ setitimer(ITIMER_REAL, &dsi->timer, NULL); /* we got some traffic from the client since the previous timer tick. */ if ((dsi->flags & DSI_DATA)) { dsi->flags &= ~DSI_DATA; return; } dsi->tickle++; LOG(log_maxdebug, logtype_afpd, "alarm: tickles: %u, flags: %s|%s|%s|%s|%s|%s|%s|%s|%s", dsi->tickle, (dsi->flags & DSI_DATA) ? "DSI_DATA" : "-", (dsi->flags & DSI_RUNNING) ? "DSI_RUNNING" : "-", (dsi->flags & DSI_SLEEPING) ? "DSI_SLEEPING" : "-", (dsi->flags & DSI_EXTSLEEP) ? "DSI_EXTSLEEP" : "-", (dsi->flags & DSI_DISCONNECTED) ? "DSI_DISCONNECTED" : "-", (dsi->flags & DSI_DIE) ? "DSI_DIE" : "-", (dsi->flags & DSI_NOREPLY) ? "DSI_NOREPLY" : "-", (dsi->flags & DSI_RECONSOCKET) ? "DSI_RECONSOCKET" : "-", (dsi->flags & DSI_RECONINPROG) ? "DSI_RECONINPROG" : "-"); if (dsi->flags & DSI_SLEEPING) { if (dsi->tickle > AFPobj->options.sleep) { LOG(log_note, logtype_afpd, "afp_alarm: sleep time ended"); afp_dsi_die(EXITERR_CLNT); } return; } if (dsi->flags & DSI_DISCONNECTED) { if (geteuid() == 0) { LOG(log_note, logtype_afpd, "afp_alarm: unauthenticated user, connection problem"); afp_dsi_die(EXITERR_CLNT); } if (dsi->tickle > AFPobj->options.disconnected) { LOG(log_error, logtype_afpd, "afp_alarm: reconnect timer expired, goodbye"); afp_dsi_die(EXITERR_CLNT); } return; } /* if we're in the midst of processing something, don't die. */ if ( !(dsi->flags & DSI_RUNNING) && (dsi->tickle >= AFPobj->options.timeout)) { LOG(log_error, logtype_afpd, "afp_alarm: child timed out, entering disconnected state"); if (dsi_disconnect(dsi) != 0) afp_dsi_die(EXITERR_CLNT); return; } if ((err = pollvoltime(AFPobj)) == 0) LOG(log_debug, logtype_afpd, "afp_alarm: sending DSI tickle"); err = dsi_tickle(AFPobj->handle); if (err <= 0) { if (geteuid() == 0) { LOG(log_note, logtype_afpd, "afp_alarm: unauthenticated user, connection problem"); afp_dsi_die(EXITERR_CLNT); } LOG(log_error, logtype_afpd, "afp_alarm: connection problem, entering disconnected state"); if (dsi_disconnect(dsi) != 0) afp_dsi_die(EXITERR_CLNT); } } /* ----------------- if dsi->in_write is set attention, tickle (and close?) msg aren't sent. We don't care about tickle */ static void pending_request(DSI *dsi) { /* send pending attention */ /* read msg if any, it could be done in afp_getsrvrmesg */ if (dsi->msg_request) { if (dsi->msg_request == 2) { /* didn't send it in signal handler */ dsi_attention(AFPobj->handle, AFPATTN_MESG | AFPATTN_TIME(5)); } dsi->msg_request = 0; readmessage(AFPobj); } if (dsi->down_request) { dsi->down_request = 0; dsi_attention(AFPobj->handle, AFPATTN_SHUTDOWN | AFPATTN_NORECONNECT | AFPATTN_MESG | AFPATTN_TIME(5)); } } /* ------------------------------------------- afp over dsi. this never returns. */ void afp_over_dsi(AFPObj *obj) { DSI *dsi = (DSI *) obj->handle; int rc_idx; u_int32_t err, cmd; u_int8_t function; struct sigaction action; AFPobj = obj; dsi->AFPobj = obj; obj->exit = afp_dsi_die; obj->reply = (int (*)()) dsi_cmdreply; obj->attention = (int (*)(void *, AFPUserBytes)) dsi_attention; dsi->tickle = 0; memset(&action, 0, sizeof(action)); sigfillset(&action.sa_mask); action.sa_flags = SA_RESTART; /* install SIGHUP */ action.sa_handler = afp_dsi_reload; if ( sigaction( SIGHUP, &action, NULL ) < 0 ) { LOG(log_error, logtype_afpd, "afp_over_dsi: sigaction: %s", strerror(errno) ); afp_dsi_die(EXITERR_SYS); } /* install SIGURG */ action.sa_handler = afp_dsi_transfer_session; if ( sigaction( SIGURG, &action, NULL ) < 0 ) { LOG(log_error, logtype_afpd, "afp_over_dsi: sigaction: %s", strerror(errno) ); afp_dsi_die(EXITERR_SYS); } /* install SIGTERM */ action.sa_handler = afp_dsi_die; if ( sigaction( SIGTERM, &action, NULL ) < 0 ) { LOG(log_error, logtype_afpd, "afp_over_dsi: sigaction: %s", strerror(errno) ); afp_dsi_die(EXITERR_SYS); } /* install SIGQUIT */ action.sa_handler = ipc_reconnect_handler; if ( sigaction(SIGQUIT, &action, NULL ) < 0 ) { LOG(log_error, logtype_afpd, "afp_over_dsi: sigaction: %s", strerror(errno) ); afp_dsi_die(EXITERR_SYS); } /* SIGUSR2 - server message support */ action.sa_handler = afp_dsi_getmesg; if ( sigaction( SIGUSR2, &action, NULL) < 0 ) { LOG(log_error, logtype_afpd, "afp_over_dsi: sigaction: %s", strerror(errno) ); afp_dsi_die(EXITERR_SYS); } /* SIGUSR1 - set down in 5 minutes */ action.sa_handler = afp_dsi_timedown; action.sa_flags = SA_RESTART; if ( sigaction( SIGUSR1, &action, NULL) < 0 ) { LOG(log_error, logtype_afpd, "afp_over_dsi: sigaction: %s", strerror(errno) ); afp_dsi_die(EXITERR_SYS); } /* SIGINT - enable max_debug LOGging to /tmp/afpd.PID.XXXXXX */ action.sa_handler = afp_dsi_debug; if ( sigaction( SIGINT, &action, NULL) < 0 ) { LOG(log_error, logtype_afpd, "afp_over_dsi: sigaction: %s", strerror(errno) ); afp_dsi_die(EXITERR_SYS); } #ifndef DEBUGGING /* SIGALRM - tickle handler */ action.sa_handler = alarm_handler; if ((sigaction(SIGALRM, &action, NULL) < 0) || (setitimer(ITIMER_REAL, &dsi->timer, NULL) < 0)) { afp_dsi_die(EXITERR_SYS); } #endif /* DEBUGGING */ if (dircache_init(obj->options.dircachesize) != 0) afp_dsi_die(EXITERR_SYS); /* set TCP snd/rcv buf */ if (obj->options.tcp_rcvbuf) { if (setsockopt(dsi->socket, SOL_SOCKET, SO_RCVBUF, &obj->options.tcp_rcvbuf, sizeof(obj->options.tcp_rcvbuf)) != 0) { LOG(log_error, logtype_dsi, "afp_over_dsi: setsockopt(SO_RCVBUF): %s", strerror(errno)); } } if (obj->options.tcp_sndbuf) { if (setsockopt(dsi->socket, SOL_SOCKET, SO_SNDBUF, &obj->options.tcp_sndbuf, sizeof(obj->options.tcp_sndbuf)) != 0) { LOG(log_error, logtype_dsi, "afp_over_dsi: setsockopt(SO_SNDBUF): %s", strerror(errno)); } } /* get stuck here until the end */ while (1) { if (sigsetjmp(recon_jmp, 1) != 0) /* returning from SIGALARM handler for a primary reconnect */ continue; /* Blocking read on the network socket */ cmd = dsi_receive(dsi); if (cmd == 0) { /* cmd == 0 is the error condition */ if (dsi->flags & DSI_RECONSOCKET) { /* we just got a reconnect so we immediately try again to receive on the new fd */ dsi->flags &= ~DSI_RECONSOCKET; continue; } /* the client sometimes logs out (afp_logout) but doesn't close the DSI session */ if (dsi->flags & DSI_AFP_LOGGED_OUT) { LOG(log_note, logtype_afpd, "afp_over_dsi: client logged out, terminating DSI session"); afp_dsi_close(obj); exit(0); } /* got ECONNRESET in read from client => exit*/ if (dsi->flags & DSI_GOT_ECONNRESET) { LOG(log_note, logtype_afpd, "afp_over_dsi: client connection reset"); afp_dsi_close(obj); exit(0); } /* Some error on the client connection, enter disconnected state */ if (dsi_disconnect(dsi) != 0) afp_dsi_die(EXITERR_CLNT); pause(); /* gets interrupted by SIGALARM or SIGURG tickle */ continue; /* continue receiving until disconnect timer expires * or a primary reconnect succeeds */ } if (!(dsi->flags & DSI_EXTSLEEP) && (dsi->flags & DSI_SLEEPING)) { LOG(log_debug, logtype_afpd, "afp_over_dsi: got data, ending normal sleep"); dsi->flags &= ~DSI_SLEEPING; dsi->tickle = 0; } if (reload_request) { reload_request = 0; load_volumes(AFPobj); } /* The first SIGINT enables debugging, the next restores the config */ if (debug_request) { static int debugging = 0; debug_request = 0; dircache_dump(); uuidcache_dump(); if (debugging) { if (obj->options.logconfig) setuplog(obj->options.logconfig); else setuplog("default log_note"); debugging = 0; } else { char logstr[50]; debugging = 1; sprintf(logstr, "default log_maxdebug /tmp/afpd.%u.XXXXXX", getpid()); setuplog(logstr); } } dsi->flags |= DSI_DATA; dsi->tickle = 0; switch(cmd) { case DSIFUNC_CLOSE: LOG(log_debug, logtype_afpd, "DSI: close session request"); afp_dsi_close(obj); LOG(log_note, logtype_afpd, "done"); exit(0); case DSIFUNC_TICKLE: dsi->flags &= ~DSI_DATA; /* thats no data in the sense we use it in alarm_handler */ LOG(log_debug, logtype_afpd, "DSI: client tickle"); /* timer is not every 30 seconds anymore, so we don't get killed on the client side. */ if ((dsi->flags & DSI_DIE)) dsi_tickle(dsi); break; case DSIFUNC_CMD: #ifdef AFS if ( writtenfork ) { if ( flushfork( writtenfork ) < 0 ) { LOG(log_error, logtype_afpd, "main flushfork: %s", strerror(errno) ); } writtenfork = NULL; } #endif /* AFS */ function = (u_char) dsi->commands[0]; /* AFP replay cache */ rc_idx = dsi->clientID % REPLAYCACHE_SIZE; LOG(log_debug, logtype_afpd, "DSI request ID: %u", dsi->clientID); if (replaycache[rc_idx].DSIreqID == dsi->clientID && replaycache[rc_idx].AFPcommand == function) { LOG(log_note, logtype_afpd, "AFP Replay Cache match: id: %u / cmd: %s", dsi->clientID, AfpNum2name(function)); err = replaycache[rc_idx].result; /* AFP replay cache end */ } else { /* send off an afp command. in a couple cases, we take advantage * of the fact that we're a stream-based protocol. */ if (afp_switch[function]) { dsi->datalen = DSI_DATASIZ; dsi->flags |= DSI_RUNNING; LOG(log_debug, logtype_afpd, "<== Start AFP command: %s", AfpNum2name(function)); err = (*afp_switch[function])(obj, (char *)&dsi->commands, dsi->cmdlen, (char *)&dsi->data, &dsi->datalen); LOG(log_debug, logtype_afpd, "==> Finished AFP command: %s -> %s", AfpNum2name(function), AfpErr2name(err)); dir_free_invalid_q(); #ifdef FORCE_UIDGID /* bring everything back to old euid, egid */ if (obj->force_uid) restore_uidgid ( &obj->uidgid ); #endif /* FORCE_UIDGID */ dsi->flags &= ~DSI_RUNNING; /* Add result to the AFP replay cache */ replaycache[rc_idx].DSIreqID = dsi->clientID; replaycache[rc_idx].AFPcommand = function; replaycache[rc_idx].result = err; } else { LOG(log_error, logtype_afpd, "bad function %X", function); dsi->datalen = 0; err = AFPERR_NOOP; } } /* single shot toggle that gets set by dsi_readinit. */ if (dsi->flags & DSI_NOREPLY) { dsi->flags &= ~DSI_NOREPLY; break; } if (!dsi_cmdreply(dsi, err)) { LOG(log_error, logtype_afpd, "dsi_cmdreply(%d): %s", dsi->socket, strerror(errno) ); if (dsi_disconnect(dsi) != 0) afp_dsi_die(EXITERR_CLNT); } break; case DSIFUNC_WRITE: /* FPWrite and FPAddIcon */ function = (u_char) dsi->commands[0]; if ( afp_switch[ function ] != NULL ) { dsi->datalen = DSI_DATASIZ; dsi->flags |= DSI_RUNNING; LOG(log_debug, logtype_afpd, "<== Start AFP command: %s", AfpNum2name(function)); err = (*afp_switch[function])(obj, (char *)&dsi->commands, dsi->cmdlen, (char *)&dsi->data, &dsi->datalen); LOG(log_debug, logtype_afpd, "==> Finished AFP command: %s -> %s", AfpNum2name(function), AfpErr2name(err)); dsi->flags &= ~DSI_RUNNING; #ifdef FORCE_UIDGID /* bring everything back to old euid, egid */ if (obj->force_uid) restore_uidgid ( &obj->uidgid ); #endif /* FORCE_UIDGID */ } else { LOG(log_error, logtype_afpd, "(write) bad function %x", function); dsi->datalen = 0; err = AFPERR_NOOP; } if (!dsi_wrtreply(dsi, err)) { LOG(log_error, logtype_afpd, "dsi_wrtreply: %s", strerror(errno) ); if (dsi_disconnect(dsi) != 0) afp_dsi_die(EXITERR_CLNT); } break; case DSIFUNC_ATTN: /* attention replies */ break; /* error. this usually implies a mismatch of some kind * between server and client. if things are correct, * we need to flush the rest of the packet if necessary. */ default: LOG(log_info, logtype_afpd,"afp_dsi: spurious command %d", cmd); dsi_writeinit(dsi, dsi->data, DSI_DATASIZ); dsi_writeflush(dsi); break; } pending_request(dsi); vol_fce_tm_event(); } /* error */ afp_dsi_die(EXITERR_CLNT); }