/* * This file is distributed as part of the MariaDB Corporation MaxScale. It is free * software: you can redistribute it and/or modify it under the terms of the * GNU General Public License as published by the Free Software Foundation, * version 2. * * This program 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 General Public License for more * details. * * You should have received a copy of the GNU General Public License along with * this program; if not, write to the Free Software Foundation, Inc., 51 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. * * Copyright MariaDB Corporation Ab 2013-2014 */ /** * @file dcb.c - Descriptor Control Block generic functions * * Descriptor control blocks provide the key mechanism for the interface * with the non-blocking socket polling routines. The descriptor control * block is the user data that is handled by the epoll system and contains * the state data and pointers to other components that relate to the * use of a file descriptor. * * @verbatim * Revision History * * Date Who Description * 12/06/13 Mark Riddoch Initial implementation * 21/06/13 Massimiliano Pinto free_dcb is used * 25/06/13 Massimiliano Pinto Added checks to session and router_session * 28/06/13 Mark Riddoch Changed the free mechanism to * introduce a zombie state for the * dcb * 02/07/2013 Massimiliano Pinto Addition of delayqlock, delayq and * authlock for handling backend * asynchronous protocol connection * and a generic lock for backend * authentication * 16/07/2013 Massimiliano Pinto Added command type for dcb * 23/07/2013 Mark Riddoch Tidy up logging * 02/09/2013 Massimiliano Pinto Added session refcount * 27/09/2013 Massimiliano Pinto dcb_read returns 0 if ioctl returns no * error and 0 bytes to read. * This fixes a bug with many reads from * backend * 07/05/2014 Mark Riddoch Addition of callback mechanism * 20/06/2014 Mark Riddoch Addition of dcb_clone * 29/05/2015 Markus Makela Addition of dcb_write_SSL * 11/06/2015 Martin Brampton Persistent connnections and tidy up * 07/07/2015 Martin Brampton Merged add to zombieslist into dcb_close, * fixes for various error situations, * remove dcb_set_state etc, simplifications. * 10/07/2015 Martin Brampton Simplify, merge dcb_read and dcb_read_n * * @endverbatim */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /** Defined in log_manager.cc */ extern int lm_enabled_logfiles_bitmask; extern size_t log_ses_count[]; extern __thread log_info_t tls_log_info; static DCB *allDCBs = NULL; /* Diagnostics need a list of DCBs */ static DCB *zombies = NULL; static SPINLOCK dcbspin = SPINLOCK_INIT; static SPINLOCK zombiespin = SPINLOCK_INIT; static void dcb_final_free(DCB *dcb); static void dcb_call_callback(DCB *dcb, DCB_REASON reason); static DCB * dcb_get_next (DCB *dcb); static int dcb_null_write(DCB *dcb, GWBUF *buf); static int dcb_null_close(DCB *dcb); static int dcb_null_auth(DCB *dcb, SERVER *server, SESSION *session, GWBUF *buf); static inline int dcb_isvalid_nolock(DCB *dcb); static inline DCB * dcb_find_in_list(DCB *dcb); static inline void dcb_process_victim_queue(DCB *listofdcb); static void dcb_close_finish(DCB *); static bool dcb_maybe_add_persistent(DCB *); static inline bool dcb_write_parameter_check(DCB *dcb, GWBUF *queue); #if defined(FAKE_CODE) static inline void dcb_write_fake_code(DCB *dcb); #endif static inline void dcb_write_when_already_queued(DCB *dcb, GWBUF *queue); static void dcb_log_write_failure(DCB *dcb, GWBUF *queue, int eno); static inline void dcb_write_tidy_up(DCB *dcb, bool below_water); static int dcb_write_SSL_error_report (DCB *dcb, int ret); size_t dcb_get_session_id( DCB *dcb) { return (dcb && dcb->session) ? dcb->session->ses_id : 0; } /** * Read log info from session through DCB and store values to memory locations * passed as parameters. * * @param dcb DCB * @param sesid location where session id is to be copied * @param enabled_logs bit field indicating which log types are enabled for the * session * *@return true if call arguments included memory addresses, false if any of the *parameters was NULL. */ bool dcb_get_ses_log_info( DCB *dcb, size_t *sesid, int *enabled_logs) { if (sesid && enabled_logs && dcb && dcb->session) { *sesid = dcb->session->ses_id; *enabled_logs = dcb->session->ses_enabled_logs; return true; } return false; } /** * Return the pointer to the list of zombie DCB's * * @return Zombies DCB list */ DCB * dcb_get_zombies(void) { return zombies; } /** * Allocate a new DCB. * * This routine performs the generic initialisation on the DCB before returning * the newly allocated DCB. * * @param dcb_role_t The role for the new DCB * @return A newly allocated DCB or NULL if non could be allocated. */ DCB * dcb_alloc(dcb_role_t role) { DCB *newdcb; if ((newdcb = calloc(1, sizeof(DCB))) == NULL) { return NULL; } newdcb->dcb_chk_top = CHK_NUM_DCB; newdcb->dcb_chk_tail = CHK_NUM_DCB; newdcb->dcb_errhandle_called = false; newdcb->dcb_role = role; spinlock_init(&newdcb->dcb_initlock); spinlock_init(&newdcb->writeqlock); spinlock_init(&newdcb->delayqlock); spinlock_init(&newdcb->authlock); spinlock_init(&newdcb->cb_lock); spinlock_init(&newdcb->pollinlock); spinlock_init(&newdcb->polloutlock); newdcb->pollinbusy = 0; newdcb->readcheck = 0; newdcb->polloutbusy = 0; newdcb->writecheck = 0; newdcb->fd = DCBFD_CLOSED; newdcb->evq.next = NULL; newdcb->evq.prev = NULL; newdcb->evq.pending_events = 0; newdcb->evq.processing = 0; spinlock_init(&newdcb->evq.eventqlock); memset(&newdcb->stats, 0, sizeof(DCBSTATS)); // Zero the statistics newdcb->state = DCB_STATE_ALLOC; bitmask_init(&newdcb->memdata.bitmask); newdcb->writeqlen = 0; newdcb->high_water = 0; newdcb->low_water = 0; newdcb->session = NULL; newdcb->server = NULL; newdcb->service = NULL; newdcb->next = NULL; newdcb->nextpersistent = NULL; newdcb->persistentstart = 0; newdcb->callbacks = NULL; newdcb->data = NULL; newdcb->remote = NULL; newdcb->user = NULL; newdcb->flags = 0; spinlock_acquire(&dcbspin); if (allDCBs == NULL) allDCBs = newdcb; else { DCB *ptr = allDCBs; while (ptr->next) ptr = ptr->next; ptr->next = newdcb; } spinlock_release(&dcbspin); return newdcb; } /** * Free a DCB that has not been associated with a descriptor. * * @param dcb The DCB to free */ void dcb_free(DCB *dcb) { if (dcb->fd != DCBFD_CLOSED) { LOGIF(LE, (skygw_log_write_flush( LOGFILE_ERROR, "Error : Attempt to free a DCB via dcb_free " "that has been associated with a descriptor."))); } raise(SIGABRT); /* Another statement to avoid a compiler warning */ dcb_final_free(dcb); } /* * Clone a DCB for internal use, mostly used for specialist filters * to create dummy clients based on real clients. * * @param orig The DCB to clone * @return A DCB that can be used as a client */ DCB * dcb_clone(DCB *orig) { DCB *clonedcb; if ((clonedcb = dcb_alloc(DCB_ROLE_REQUEST_HANDLER))) { clonedcb->fd = DCBFD_CLOSED; clonedcb->flags |= DCBF_CLONE; clonedcb->state = orig->state; clonedcb->data = orig->data; if (orig->remote) clonedcb->remote = strdup(orig->remote); if (orig->user) clonedcb->user = strdup(orig->user); clonedcb->protocol = orig->protocol; clonedcb->func.write = dcb_null_write; /** * Close triggers closing of router session as well which is needed. */ clonedcb->func.close = orig->func.close; clonedcb->func.auth = dcb_null_auth; } return clonedcb; } /** * Free a DCB and remove it from the chain of all DCBs * * NB This is called with the caller holding the zombie queue * spinlock * * @param dcb The DCB to free */ static void dcb_final_free(DCB *dcb) { DCB_CALLBACK *cb; CHK_DCB(dcb); ss_info_dassert(dcb->state == DCB_STATE_DISCONNECTED || dcb->state == DCB_STATE_ALLOC, "dcb not in DCB_STATE_DISCONNECTED not in DCB_STATE_ALLOC state."); if (DCB_POLL_BUSY(dcb)) { /* Check if DCB has outstanding poll events */ LOGIF(LE, (skygw_log_write_flush( LOGFILE_ERROR, "dcb_final_free: DCB %p has outstanding events", dcb))); } /*< First remove this DCB from the chain */ spinlock_acquire(&dcbspin); if (allDCBs == dcb) { /*< * Deal with the special case of removing the DCB at the head of * the chain. */ allDCBs = dcb->next; } else { /*< * We find the DCB that point to the one we are removing and then * set the next pointer of that DCB to the next pointer of the * DCB we are removing. */ DCB *ptr = allDCBs; while (ptr && ptr->next != dcb) ptr = ptr->next; if (ptr) ptr->next = dcb->next; } spinlock_release(&dcbspin); if (dcb->session) { /*< * Terminate client session. */ { SESSION *local_session = dcb->session; dcb->session = NULL; CHK_SESSION(local_session); /** * Set session's client pointer NULL so that other threads * won't try to call dcb_close for client DCB * after this call. */ if (local_session->client == dcb) { spinlock_acquire(&local_session->ses_lock); local_session->client = NULL; spinlock_release(&local_session->ses_lock); } session_free(local_session); } } if (dcb->protocol && (!DCB_IS_CLONE(dcb))) free(dcb->protocol); if (dcb->protoname) free(dcb->protoname); if (dcb->remote) free(dcb->remote); if (dcb->user) free(dcb->user); /* Clear write and read buffers */ if (dcb->delayq) { GWBUF *queue = dcb->delayq; while ((queue = gwbuf_consume(queue, GWBUF_LENGTH(queue))) != NULL); } if (dcb->dcb_readqueue) { GWBUF* queue = dcb->dcb_readqueue; while ((queue = gwbuf_consume(queue, GWBUF_LENGTH(queue))) != NULL); } spinlock_acquire(&dcb->cb_lock); while ((cb = dcb->callbacks) != NULL) { dcb->callbacks = cb->next; free(cb); } spinlock_release(&dcb->cb_lock); if(dcb->ssl) SSL_free(dcb->ssl); bitmask_free(&dcb->memdata.bitmask); free(dcb); } /** * Process the DCB zombie queue * * This routine is called by each of the polling threads with * the thread id of the polling thread. It must clear the bit in * the memdata bitmask for the polling thread that calls it. If the * operation of clearing this bit means that no bits are set in * the memdata.bitmask then the DCB is no longer able to be * referenced and it can be finally removed. * * @param threadid The thread ID of the caller */ DCB * dcb_process_zombies(int threadid) { DCB *zombiedcb, *previousdcb; DCB *listofdcb = NULL; DCB *dcb = NULL; bool succp = false; /** * Perform a dirty read to see if there is anything in the queue. * This avoids threads hitting the queue spinlock when the queue * is empty. This will really help when the only entry is being * freed, since the queue is updated before the expensive call to * dcb_final_free. */ if (!zombies) return NULL; /* * Process the zombie queue and create a list of DCB's that can be * finally freed. This processing is down under a spinlock that * will prevent new entries being added to the zombie queue. Therefore * we do not want to do any expensive operations under this spinlock * as it will block other threads. The expensive operations will be * performed on the victim queue within holding the zombie queue * spinlock. */ spinlock_acquire(&zombiespin); zombiedcb = zombies; previousdcb = NULL; while (zombiedcb) { CHK_DCB(zombiedcb); /* * Skip processing of DCB's that are * in the event queue waiting to be processed. */ if (zombiedcb->evq.next || zombiedcb->evq.prev) { previousdcb = zombiedcb; zombiedcb = zombiedcb->memdata.next; } else { bitmask_clear(&zombiedcb->memdata.bitmask, threadid); if (bitmask_isallclear(&zombiedcb->memdata.bitmask)) { /** * Remove the DCB from the zombie queue * and call the final free routine for the * DCB * * zombiedcb is the DCB we are processing * previousdcb is the previous DCB on the zombie * queue or NULL if the DCB is at the head of the * queue. Remove zombiedcb from the zombies list. */ if (previousdcb == NULL) zombies = zombiedcb->memdata.next; else previousdcb->memdata.next = zombiedcb->memdata.next; LOGIF(LD, (skygw_log_write_flush( LOGFILE_DEBUG, "%lu [dcb_process_zombies] Remove dcb " "%p fd %d in state %s from the " "list of zombies.", pthread_self(), zombiedcb, zombiedcb->fd, STRDCBSTATE(zombiedcb->state)))); ss_info_dassert(zombiedcb->state == DCB_STATE_ZOMBIE, "dcb not in DCB_STATE_ZOMBIE state."); /*< * Move zombie dcb to linked list of victim dcbs. * The variable dcb is used to hold the last DCB * to have been added to the linked list, or NULL * if none has yet been added. If the list * (listofdcb) is not NULL, then it follows that * dcb will also not be null. */ if (listofdcb == NULL) { listofdcb = zombiedcb; } else { dcb->memdata.next = zombiedcb; } /* Set dcb for next iteration of loop */ dcb = zombiedcb; zombiedcb = zombiedcb->memdata.next; /* After we've moved zombiedcb forward, set link to null as dcb is last of the new list */ dcb->memdata.next = NULL; } else { /* Since we didn't remove this dcb from the zombies list, we need to advance the previous pointer */ previousdcb = zombiedcb; zombiedcb = zombiedcb->memdata.next; } } } spinlock_release(&zombiespin); dcb_process_victim_queue(listofdcb); return zombies; } /** * Process the victim queue, selected from the list of zombies * * These are the DCBs that are not in use by any thread. The corresponding * file descriptor is closed, the DCB marked as disconnected and the DCB * itself is finally freed. * * @param listofdcb The first victim DCB */ static inline void dcb_process_victim_queue(DCB *listofdcb) { DCB *dcb; dcb = listofdcb; while (dcb != NULL) { DCB *nextdcb = NULL; if (dcb->fd > 0) { /*< * Close file descriptor and move to clean-up phase. */ if (close(dcb->fd) < 0) { int eno = errno; errno = 0; LOGIF(LE, (skygw_log_write_flush( LOGFILE_ERROR, "%lu [dcb_process_victim_queue] Error : Failed to close " "socket %d on dcb %p due error %d, %s.", pthread_self(), dcb->fd, dcb, eno, strerror(eno)))); } else { dcb->fd = DCBFD_CLOSED; LOGIF(LD, (skygw_log_write_flush( LOGFILE_DEBUG, "%lu [dcb_process_victim_queue] Closed socket " "%d on dcb %p.", pthread_self(), dcb->fd, dcb))); #if defined(FAKE_CODE) conn_open[dcb->fd] = false; #endif /* FAKE_CODE */ } } LOGIF_MAYBE(LT, (dcb_get_ses_log_info( dcb, &tls_log_info.li_sesid, &tls_log_info.li_enabled_logs))); dcb->state = DCB_STATE_DISCONNECTED; nextdcb = dcb->memdata.next; dcb_final_free(dcb); dcb = nextdcb; } /** Reset threads session data */ LOGIF(LT, tls_log_info.li_sesid = 0); } /** * Connect to a server * * This routine will create a server connection * If successful the new dcb will be put in * epoll set by dcb->func.connect * * @param server The server to connect to * @param session The session this connection is being made for * @param protocol The protocol module to use * @return The new allocated dcb or NULL if the DCB was not connected */ DCB * dcb_connect(SERVER *server, SESSION *session, const char *protocol) { DCB *dcb; GWPROTOCOL *funcs; int fd; int rc; char *user; user = session_getUser(session); if (user && strlen(user)) { LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_connect] Looking for persistent connection DCB user %s protocol %s\n", pthread_self(), user, protocol))); dcb = server_get_persistent(server, user, protocol); if (dcb) { /** * Link dcb to session. Unlink is called in dcb_final_free */ if (!session_link_dcb(session, dcb)) { LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_connect] Failed to link to session, the " "session has been removed.\n", pthread_self()))); dcb_close(dcb); return NULL; } LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_connect] Reusing a persistent connection, dcb %p\n", pthread_self(), dcb))); dcb->persistentstart = 0; return dcb; } else { LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_connect] Failed to find a reusable persistent connection.\n", pthread_self()))); } } if ((dcb = dcb_alloc(DCB_ROLE_REQUEST_HANDLER)) == NULL) { return NULL; } if ((funcs = (GWPROTOCOL *)load_module(protocol, MODULE_PROTOCOL)) == NULL) { dcb->state = DCB_STATE_DISCONNECTED; dcb_final_free(dcb); LOGIF(LE, (skygw_log_write_flush( LOGFILE_ERROR, "Error : Failed to load protocol module for %s, free " "dcb %p\n", protocol, dcb))); return NULL; } memcpy(&(dcb->func), funcs, sizeof(GWPROTOCOL)); dcb->protoname = strdup(protocol); /** * Link dcb to session. Unlink is called in dcb_final_free */ if (!session_link_dcb(session, dcb)) { LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_connect] Failed to link to session, the " "session has been removed.", pthread_self()))); dcb_final_free(dcb); return NULL; } fd = dcb->func.connect(dcb, server, session); if (fd == DCBFD_CLOSED) { LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_connect] Failed to connect to server %s:%d, " "from backend dcb %p, client dcp %p fd %d.", pthread_self(), server->name, server->port, dcb, session->client, session->client->fd))); dcb->state = DCB_STATE_DISCONNECTED; dcb_final_free(dcb); return NULL; } else { LOGIF(LD, (skygw_log_write_flush( LOGFILE_DEBUG, "%lu [dcb_connect] Connected to server %s:%d, " "from backend dcb %p, client dcp %p fd %d.", pthread_self(), server->name, server->port, dcb, session->client, session->client->fd))); } ss_dassert(dcb->fd == DCBFD_CLOSED); /*< must be uninitialized at this point */ /** * Successfully connected to backend. Assign file descriptor to dcb */ dcb->fd = fd; /** * Add server pointer to dcb */ dcb->server = server; /** Copy status field to DCB */ dcb->dcb_server_status = server->status; dcb->dcb_port = server->port; /** * backend_dcb is connected to backend server, and once backend_dcb * is added to poll set, authentication takes place as part of * EPOLLOUT event that will be received once the connection * is established. */ /** * Add the dcb in the poll set */ rc = poll_add_dcb(dcb); if (rc) { dcb->state = DCB_STATE_DISCONNECTED; dcb_final_free(dcb); return NULL; } /** * The dcb will be addded into poll set by dcb->func.connect */ atomic_add(&server->stats.n_connections, 1); atomic_add(&server->stats.n_current, 1); return dcb; } /** * General purpose read routine to read data from a socket in the * Descriptor Control Block and append it to a linked list of buffers. * The list may be empty, in which case *head == NULL. The third * parameter indicates the maximum number of bytes to be read (needed * for SSL processing) with 0 meaning no limit. * * @param dcb The DCB to read from * @param head Pointer to linked list to append data to * @param maxbytes Maximum bytes to read (0 = no limit) * @return -1 on error, otherwise the number of read bytes on * the last iteration of while loop. 0 is returned if no data available. */ int dcb_read( DCB *dcb, GWBUF **head, int maxbytes) { GWBUF *buffer = NULL; int bytesavailable; int nsingleread = 0; int nreadtotal = 0; CHK_DCB(dcb); if (dcb->fd <= 0) { /* */ LOGIF(LE, (skygw_log_write_flush( LOGFILE_ERROR, "%lu [dcb_read] Error : Read failed, dcb is %s.", pthread_self(), dcb->fd == DCBFD_CLOSED ? "closed" : "cloned, not readable"))); /* */ return 0; } while (0 == maxbytes || nreadtotal < maxbytes) { int bufsize; if (-1 == ioctl(dcb->fd, FIONREAD, &bytesavailable)) { /* */ LOGIF(LE, (skygw_log_write_flush( LOGFILE_ERROR, "%lu [dcb_read] Error : ioctl FIONREAD for dcb %p in " "state %s fd %d failed due error %d, %s.", pthread_self(), dcb, STRDCBSTATE(dcb->state), dcb->fd, errno, strerror(errno)))); /* */ return -1; } if (bytesavailable == 0) { /** Handle closed client socket */ if (nreadtotal == 0 && dcb_isclient(dcb)) { char c; int l_errno = 0; int r = -1; /* try to read 1 byte, without consuming the socket buffer */ r = recv(dcb->fd, &c, sizeof(char), MSG_PEEK); l_errno = errno; if (r <= 0 && l_errno != EAGAIN && l_errno != EWOULDBLOCK && l_errno != 0) { return -1; } } return 0; } dcb->last_read = hkheartbeat; bufsize = MIN(bytesavailable, MAX_BUFFER_SIZE); if (maxbytes) bufsize = MIN(bufsize, maxbytes-nreadtotal); if ((buffer = gwbuf_alloc(bufsize)) == NULL) { /*< * This is a fatal error which should cause shutdown. * Todo shutdown if memory allocation fails. */ /* */ LOGIF(LE, (skygw_log_write_flush( LOGFILE_ERROR, "%lu [dcb_read] Error : Failed to allocate read buffer " "for dcb %p fd %d, due %d, %s.", pthread_self(), dcb, dcb->fd, errno, strerror(errno)))); /* */ return -1; } GW_NOINTR_CALL(nsingleread = read(dcb->fd, GWBUF_DATA(buffer), bufsize); dcb->stats.n_reads++); if (nsingleread <= 0) { if (errno != 0 && errno != EAGAIN && errno != EWOULDBLOCK) { /* */ LOGIF(LE, (skygw_log_write_flush( LOGFILE_ERROR, "%lu [dcb_read] Error : Read failed, dcb %p in state " "%s fd %d, due %d, %s.", pthread_self(), dcb, STRDCBSTATE(dcb->state), dcb->fd, errno, strerror(errno)))); /* */ } gwbuf_free(buffer); return nsingleread; } nreadtotal += nsingleread; /* */ LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_read] Read %d bytes from dcb %p in state %s " "fd %d.", pthread_self(), nsingleread, dcb, STRDCBSTATE(dcb->state), dcb->fd))); /* */ /*< Append read data to the gwbuf */ *head = gwbuf_append(*head, buffer); } /*< while (0 == maxbytes || nreadtotal < maxbytes) */ return nsingleread; } /** * General purpose read routine to read data from a socket through the SSL * structure lined with this DCB and append it to a linked list of buffers. * The list may be empty, in which case *head == NULL. The SSL structure should * be initialized and the SSL handshake should be done. * * @param dcb The DCB to read from * @param head Pointer to linked list to append data to * @return -1 on error, otherwise the number of read bytes on the last * iteration of while loop. 0 is returned if no data available. */ int dcb_read_SSL( DCB *dcb, GWBUF **head) { GWBUF *buffer = NULL; int b,pending; int rc; int n; int nread = 0; int ssl_errno = 0; CHK_DCB(dcb); if (dcb->fd <= 0) { LOGIF(LE, (skygw_log_write_flush( LOGFILE_ERROR, "Error : Read failed, dcb is %s.", dcb->fd == DCBFD_CLOSED ? "closed" : "cloned, not readable"))); n = 0; goto return_n; } while (true) { int bufsize; ssl_errno = 0; rc = ioctl(dcb->fd, FIONREAD, &b); pending = SSL_pending(dcb->ssl); if (rc == -1) { LOGIF(LE, (skygw_log_write_flush( LOGFILE_ERROR, "Error : ioctl FIONREAD for dcb %p in " "state %s fd %d failed due error %d, %s.", dcb, STRDCBSTATE(dcb->state), dcb->fd, errno, strerror(errno)))); n = -1; goto return_n; } if (b == 0 && pending == 0 && nread == 0) { /** Handle closed client socket */ if (dcb_isclient(dcb)) { char c = 0; int r = -1; /* try to read 1 byte, without consuming the socket buffer */ r = SSL_peek(dcb->ssl, &c, sizeof(char)); if (r <= 0) { ssl_errno = SSL_get_error(dcb->ssl,r); if(ssl_errno != SSL_ERROR_WANT_READ && ssl_errno != SSL_ERROR_WANT_WRITE && ssl_errno != SSL_ERROR_NONE) n = -1; else n = 0; goto return_n; } } n = 0; goto return_n; } else if (b == 0 && pending == 0) { n = 0; goto return_n; } #ifdef SS_DEBUG else { skygw_log_write_flush(LD,"Total: %d Socket: %d Pending: %d", nread,b,pending); } #endif dcb->last_read = hkheartbeat; bufsize = MIN(b, MAX_BUFFER_SIZE); if ((buffer = gwbuf_alloc(bufsize)) == NULL) { /*< * This is a fatal error which should cause shutdown. * Todo shutdown if memory allocation fails. */ LOGIF(LE, (skygw_log_write_flush( LOGFILE_ERROR, "Error : Failed to allocate read buffer " "for dcb %p fd %d, due %d, %s.", dcb, dcb->fd, errno, strerror(errno)))); n = -1; goto return_n; } n = SSL_read(dcb->ssl, GWBUF_DATA(buffer), bufsize); dcb->stats.n_reads++; if (n < 0) { char errbuf[200]; ssl_errno = SSL_get_error(dcb->ssl,n); #ifdef SS_DEBUG if(ssl_errno == SSL_ERROR_SSL || ssl_errno == SSL_ERROR_SYSCALL) { int eno; while((eno = ERR_get_error()) != 0) { ERR_error_string_n(eno,errbuf,200); skygw_log_write(LE, "%s", errbuf); } } #endif if(ssl_errno == SSL_ERROR_WANT_READ || ssl_errno == SSL_ERROR_WANT_WRITE || ssl_errno == SSL_ERROR_NONE) { n = 0; } else { LOGIF(LE, (skygw_log_write_flush( LOGFILE_ERROR, "Error : Read failed, dcb %p in state " "%s fd %d, SSL error %d: %s.", dcb, STRDCBSTATE(dcb->state), dcb->fd, ssl_errno, strerror(errno)))); if(ssl_errno == SSL_ERROR_SSL || ssl_errno == SSL_ERROR_SYSCALL) { while((ssl_errno = ERR_get_error()) != 0) { ERR_error_string_n(ssl_errno,errbuf,200); skygw_log_write(LE, "%s", errbuf); } } } n = -1; gwbuf_free(buffer); goto return_n; } else if(n == 0) { gwbuf_free(buffer); goto return_n; } buffer = gwbuf_rtrim(buffer,bufsize - n); if(buffer == NULL) { goto return_n; } #ifdef SS_DEBUG skygw_log_write(LD,"%lu SSL: Truncated buffer from %d to %d bytes. " "Read %d bytes, %d bytes waiting.\n",pthread_self(), bufsize,GWBUF_LENGTH(buffer),n,b); if(GWBUF_LENGTH(buffer) != n){ skygw_log_sync_all(); } ss_info_dassert((buffer->start <= buffer->end),"Buffer start has passed end."); ss_info_dassert(GWBUF_LENGTH(buffer) == n,"Buffer size not equal to read bytes."); #endif nread += n; LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_read_SSL] Read %d bytes from dcb %p in state %s " "fd %d.", pthread_self(), n, dcb, STRDCBSTATE(dcb->state), dcb->fd))); /*< Append read data to the gwbuf */ *head = gwbuf_append(*head, buffer); } /*< while (true) */ return_n: return nread; } /** * General purpose routine to write to a DCB * * @param dcb The DCB of the client * @param queue Queue of buffers to write */ int dcb_write(DCB *dcb, GWBUF *queue) { int written; int below_water; below_water = (dcb->high_water && dcb->writeqlen < dcb->high_water) ? 1 : 0; // The following guarantees that queue is not NULL if (!dcb_write_parameter_check(dcb, queue)) return 0; spinlock_acquire(&dcb->writeqlock); if (dcb->writeq) { dcb_write_when_already_queued(dcb, queue); } else { /* * Loop over the buffer chain that has been passed to us * from the reading side. * Send as much of the data in that chain as possible and * add any balance to the write queue. */ while (queue != NULL) { #if defined(FAKE_CODE) dcb_write_fake_code(dcb); #endif /* FAKE_CODE */ GW_NOINTR_CALL( written = gw_write(dcb, GWBUF_DATA(queue), GWBUF_LENGTH(queue)); dcb->stats.n_writes++; ); if (written < 0) { int saved_errno = errno; dcb_log_write_failure(dcb, queue, saved_errno); /*< * What wasn't successfully written is stored to write queue * for suspended write. */ atomic_add(&dcb->writeqlen, gwbuf_length(queue)); dcb->writeq = queue; dcb->stats.n_buffered++; spinlock_release(&dcb->writeqlock); /** Return 1 if the write failure was due to EWOULDBLOCK or EAGAIN. The rest of the buffer will be written once an EPOLL_OUT event arrives.*/ return saved_errno == 0 || saved_errno == EAGAIN || saved_errno == EWOULDBLOCK; } /* * Pull the number of bytes we have written from * queue with have. */ queue = gwbuf_consume(queue, written); LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_write] Wrote %d Bytes to dcb %p in " "state %s fd %d", pthread_self(), written, dcb, STRDCBSTATE(dcb->state), dcb->fd))); } /*< while (queue != NULL) */ } /* if (dcb->writeq) */ dcb_write_tidy_up(dcb, below_water); return 1; } #if defined(FAKE_CODE) /** * Fake code for dcb_write * (Should have fuller description) * * @param dcb The DCB of the client */ static inline void dcb_write_fake_code(DCB *dcb) { if (dcb->dcb_role == DCB_ROLE_REQUEST_HANDLER && dcb->session != NULL) { if (dcb_isclient(dcb) && fail_next_client_fd) { dcb_fake_write_errno[dcb->fd] = 32; dcb_fake_write_ev[dcb->fd] = 29; fail_next_client_fd = false; } else if (!dcb_isclient(dcb) && fail_next_backend_fd) { dcb_fake_write_errno[dcb->fd] = 32; dcb_fake_write_ev[dcb->fd] = 29; fail_next_backend_fd = false; } } } #endif /* FAKE_CODE */ /** * Check the parameters for dcb_write * * @param dcb The DCB of the client * @param queue Queue of buffers to write * @return true if parameters acceptable, false otherwise */ static inline bool dcb_write_parameter_check(DCB *dcb, GWBUF *queue) { if (queue == NULL) return false; if (dcb->fd <= 0) { LOGIF(LE, (skygw_log_write_flush( LOGFILE_ERROR, "Error : Write failed, dcb is %s.", dcb->fd == DCBFD_CLOSED ? "closed" : "cloned, not writable"))); gwbuf_free(queue); return false; } if (dcb->session == NULL || dcb->session->state != SESSION_STATE_STOPPING) { /** * SESSION_STATE_STOPPING means that one of the backends is closing * the router session. Some backends may have not completed * authentication yet and thus they have no information about router * being closed. Session state is changed to SESSION_STATE_STOPPING * before router's closeSession is called and that tells that DCB may * still be writable. */ if (dcb->state != DCB_STATE_ALLOC && dcb->state != DCB_STATE_POLLING && dcb->state != DCB_STATE_LISTENING && dcb->state != DCB_STATE_NOPOLLING) { LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_write] Write aborted to dcb %p because " "it is in state %s", pthread_self(), dcb->stats.n_buffered, dcb, STRDCBSTATE(dcb->state), dcb->fd))); gwbuf_free(queue); return false; } } return true; } /** * Handle writing when there is already queued data * * @param dcb The DCB of the client * @param queue Queue of buffers to write */ static inline void dcb_write_when_already_queued(DCB *dcb, GWBUF *queue) { /* * We have some queued data, so add our data to * the write queue and return. * The assumption is that there will be an EPOLLOUT * event to drain what is already queued. We are protected * by the spinlock, which will also be acquired by the * the routine that drains the queue data, so we should * not have a race condition on the event. */ atomic_add(&dcb->writeqlen, gwbuf_length(queue)); dcb->writeq = gwbuf_append(dcb->writeq, queue); dcb->stats.n_buffered++; LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_write] Append to writequeue. %d writes " "buffered for dcb %p in state %s fd %d", pthread_self(), dcb->stats.n_buffered, dcb, STRDCBSTATE(dcb->state), dcb->fd))); } /** * Debug log write failure, except when it is COM_QUIT * * @param dcb The DCB of the client * @param queue Queue of buffers to write * @param eno Error number for logging */ static void dcb_log_write_failure(DCB *dcb, GWBUF *queue, int eno) { if (LOG_IS_ENABLED(LOGFILE_DEBUG)) { if (eno == EPIPE) { LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_write] Write to dcb " "%p in state %s fd %d failed " "due errno %d, %s", pthread_self(), dcb, STRDCBSTATE(dcb->state), dcb->fd, eno, strerror(eno)))); } } if (LOG_IS_ENABLED(LOGFILE_ERROR)) { if (eno != EPIPE && eno != EAGAIN && eno != EWOULDBLOCK) { LOGIF(LE, (skygw_log_write_flush( LOGFILE_ERROR, "Error : Write to dcb %p in " "state %s fd %d failed due " "errno %d, %s", dcb, STRDCBSTATE(dcb->state), dcb->fd, eno, strerror(eno)))); } } bool dolog = true; if (eno != 0 && eno != EAGAIN && eno != EWOULDBLOCK) { /** * Do not log if writing COM_QUIT to backend failed. */ if (GWBUF_IS_TYPE_MYSQL(queue)) { uint8_t* data = GWBUF_DATA(queue); if (data[4] == 0x01) { dolog = false; } } if (dolog) { LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_write] Writing to %s socket failed due %d, %s.", pthread_self(), dcb_isclient(dcb) ? "client" : "backend server", eno, strerror(eno)))); } } } /** * Last few things to do at end of a write * * @param dcb The DCB of the client * @param below_water A boolean */ static inline void dcb_write_tidy_up (DCB *dcb, bool below_water) { spinlock_release(&dcb->writeqlock); if (dcb->high_water && dcb->writeqlen > dcb->high_water && below_water) { atomic_add(&dcb->stats.n_high_water, 1); dcb_call_callback(dcb, DCB_REASON_HIGH_WATER); } } /** * General purpose routine to write to an SSL enabled DCB * * @param dcb The DCB of the client * @param ssl The SSL structure for this DCB * @param queue Queue of buffers to write * @return 0 on failure, 1 on success */ int dcb_write_SSL(DCB *dcb, GWBUF *queue) { int w; int saved_errno = 0; bool below_water; below_water = (dcb->high_water && dcb->writeqlen < dcb->high_water) ? 1 : 0; // The following guarantees that queue is not NULL if (!dcb_write_parameter_check(dcb, queue)) return 0; spinlock_acquire(&dcb->writeqlock); if (dcb->writeq) { dcb_write_when_already_queued(dcb, queue); } else { /* * Loop over the buffer chain that has been passed to us * from the reading side. * Send as much of the data in that chain as possible and * add any balance to the write queue. */ while (queue != NULL) { #if defined(FAKE_CODE) dcb_write_fake_code(dcb); #endif /* FAKE_CODE */ do { w = gw_write_SSL(dcb->ssl, GWBUF_DATA(queue), GWBUF_LENGTH(queue)); dcb->stats.n_writes++; if (w <= 0) { int ssl_errno = dcb_write_SSL_error_report (dcb, w); if(ssl_errno != SSL_ERROR_WANT_WRITE) { atomic_add(&dcb->writeqlen, gwbuf_length(queue)); dcb->stats.n_buffered++; dcb_write_tidy_up(dcb, below_water); return 1; } } } while(w <= 0); /** Remove written bytes from the queue */ queue = gwbuf_consume(queue, w); LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_write] Wrote %d Bytes to dcb %p in " "state %s fd %d", pthread_self(), w, dcb, STRDCBSTATE(dcb->state), dcb->fd))); } /*< while (queue != NULL) */ /*< * What wasn't successfully written is stored to write queue * for suspended write. */ dcb->writeq = queue; } /* if (dcb->writeq) */ dcb_write_tidy_up(dcb, below_water); return 1; } /** * General purpose routine to write error reports for SSL writes * * @param dcb The DCB of the client * @param ret The SSL operation return code * @return The final SSL error number */ static int dcb_write_SSL_error_report (DCB *dcb, int ret) { int ssl_errno; char errbuf[256]; ssl_errno = SSL_get_error(dcb->ssl,ret); if (LOG_IS_ENABLED(LOGFILE_DEBUG)) { switch(ssl_errno) { case SSL_ERROR_WANT_READ: LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_write] Write to dcb " "%p in state %s fd %d failed " "due error SSL_ERROR_WANT_READ", pthread_self(), dcb, STRDCBSTATE(dcb->state), dcb->fd))); break; case SSL_ERROR_WANT_WRITE: LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_write] Write to dcb " "%p in state %s fd %d failed " "due error SSL_ERROR_WANT_WRITE", pthread_self(), dcb, STRDCBSTATE(dcb->state), dcb->fd))); break; default: LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_write] Write to dcb " "%p in state %s fd %d failed " "due error %d", pthread_self(), dcb, STRDCBSTATE(dcb->state), dcb->fd,ssl_errno))); break; } } if (LOG_IS_ENABLED(LOGFILE_ERROR) && ssl_errno != SSL_ERROR_WANT_WRITE) { if (ret == -1) { LOGIF(LE, (skygw_log_write_flush( LOGFILE_ERROR, "Error : Write to dcb %p in " "state %s fd %d failed due to " "SSL error %d", dcb, STRDCBSTATE(dcb->state), dcb->fd, ssl_errno))); if(ssl_errno == SSL_ERROR_SSL || ssl_errno == SSL_ERROR_SYSCALL) { if(ssl_errno == SSL_ERROR_SYSCALL) { strerror_r(errno,errbuf,255); errbuf[255] = '\0'; skygw_log_write(LE,"%d:%s",errno,errbuf); } do { char errbuf[140]; ERR_error_string_n(ssl_errno,errbuf,140); skygw_log_write(LE,"%d:%s",ssl_errno,errbuf); } while((ssl_errno = ERR_get_error()) != 0); } } else if(ret == 0) { do { char errbuf[140]; ERR_error_string_n(ssl_errno,errbuf,140); skygw_log_write(LE,"%d:%s",ssl_errno,errbuf); } while((ssl_errno = ERR_get_error()) != 0); } } return SSL_ERROR_NONE; } /** * Drain the write queue of a DCB. This is called as part of the EPOLLOUT handling * of a socket and will try to send any buffered data from the write queue * up until the point the write would block. * * @param dcb DCB to drain the write queue of * @return The number of bytes written */ int dcb_drain_writeq(DCB *dcb) { int n = 0; int w; int saved_errno = 0; int above_water; above_water = (dcb->low_water && dcb->writeqlen > dcb->low_water) ? 1 : 0; spinlock_acquire(&dcb->writeqlock); if (dcb->writeq) { int len; /* * Loop over the buffer chain in the pending writeq * Send as much of the data in that chain as possible and * leave any balance on the write queue. */ while (dcb->writeq != NULL) { len = GWBUF_LENGTH(dcb->writeq); GW_NOINTR_CALL(w = gw_write(dcb, GWBUF_DATA(dcb->writeq), len);); saved_errno = errno; errno = 0; if (w < 0) { #if defined(SS_DEBUG) if (saved_errno == EAGAIN || saved_errno == EWOULDBLOCK) #else if (saved_errno == EAGAIN || saved_errno == EWOULDBLOCK || saved_errno == EPIPE) #endif { break; } LOGIF(LE, (skygw_log_write_flush( LOGFILE_ERROR, "Error : Write to dcb %p " "in state %s fd %d failed due errno %d, %s", dcb, STRDCBSTATE(dcb->state), dcb->fd, saved_errno, strerror(saved_errno)))); break; } /* * Pull the number of bytes we have written from * queue with have. */ dcb->writeq = gwbuf_consume(dcb->writeq, w); LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_drain_writeq] Wrote %d Bytes to dcb %p " "in state %s fd %d", pthread_self(), w, dcb, STRDCBSTATE(dcb->state), dcb->fd))); n += w; } } spinlock_release(&dcb->writeqlock); atomic_add(&dcb->writeqlen, -n); /* The write queue has drained, potentially need to call a callback function */ if (dcb->writeq == NULL) dcb_call_callback(dcb, DCB_REASON_DRAINED); if (above_water && dcb->writeqlen < dcb->low_water) { atomic_add(&dcb->stats.n_low_water, 1); dcb_call_callback(dcb, DCB_REASON_LOW_WATER); } return n; } /** * Drain the write queue of a DCB. This is called as part of the EPOLLOUT handling * of a socket and will try to send any buffered data from the write queue * up until the point the write would block. This function uses SSL encryption * and the SSL handshake should have been completed prior to calling this function. * * @param dcb DCB to drain the write queue of * @return The number of bytes written */ int dcb_drain_writeq_SSL(DCB *dcb) { int n = 0; int w; int saved_errno = 0; int above_water; above_water = (dcb->low_water && dcb->writeqlen > dcb->low_water) ? 1 : 0; spinlock_acquire(&dcb->writeqlock); if (dcb->writeq) { int len; /* * Loop over the buffer chain in the pending writeq * Send as much of the data in that chain as possible and * leave any balance on the write queue. */ while (dcb->writeq != NULL) { len = GWBUF_LENGTH(dcb->writeq); w = gw_write_SSL(dcb->ssl, GWBUF_DATA(dcb->writeq), len); if (w < 0) { int ssl_errno = SSL_get_error(dcb->ssl,w); if(ssl_errno == SSL_ERROR_WANT_WRITE || ssl_errno == SSL_ERROR_WANT_READ) { break; } skygw_log_write_flush(LOGFILE_ERROR, "Error : Write to dcb failed due to " "SSL error %d:", dcb, STRDCBSTATE(dcb->state), dcb->fd, ssl_errno); switch(ssl_errno) { case SSL_ERROR_SSL: case SSL_ERROR_SYSCALL: while((ssl_errno = ERR_get_error()) != 0) { char errbuf[140]; ERR_error_string_n(ssl_errno,errbuf,140); skygw_log_write(LE,"%s",errbuf); } if(errno != 0) skygw_log_write(LE,"%d:%s",errno,strerror(errno)); break; case SSL_ERROR_ZERO_RETURN: skygw_log_write(LE,"Socket is closed."); break; default: skygw_log_write(LE,"Unexpected error."); break; } break; } /* * Pull the number of bytes we have written from * queue with have. */ dcb->writeq = gwbuf_consume(dcb->writeq, w); n += w; } } spinlock_release(&dcb->writeqlock); atomic_add(&dcb->writeqlen, -n); /* The write queue has drained, potentially need to call a callback function */ if (dcb->writeq == NULL) dcb_call_callback(dcb, DCB_REASON_DRAINED); if (above_water && dcb->writeqlen < dcb->low_water) { atomic_add(&dcb->stats.n_low_water, 1); dcb_call_callback(dcb, DCB_REASON_LOW_WATER); } return n; } /** * Removes dcb from poll set, and adds it to zombies list. As a consequence, * dcb first moves to DCB_STATE_NOPOLLING, and then to DCB_STATE_ZOMBIE state. * At the end of the function state may not be DCB_STATE_ZOMBIE because once * dcb_initlock is released parallel threads may change the state. * * Parameters: * @param dcb The DCB to close * * */ void dcb_close(DCB *dcb) { CHK_DCB(dcb); LOGIF(LD, (skygw_log_write(LOGFILE_DEBUG, "%lu [dcb_close] DCB %p in state %s", pthread_self(), dcb, dcb ? STRDCBSTATE(dcb->state) : "Invalid DCB"))); if (DCB_STATE_ZOMBIE == dcb->state) { return; } if (DCB_STATE_UNDEFINED == dcb->state || DCB_STATE_DISCONNECTED == dcb->state) { LOGIF(LE, (skygw_log_write( LOGFILE_ERROR, "%lu [dcb_close] Error : Removing DCB %p but was in state %s " "which is not legal for a call to dcb_close. ", pthread_self(), dcb, STRDCBSTATE(dcb->state)))); raise(SIGABRT); } /** * dcb_close may be called for freshly created dcb, in which case * it only needs to be freed. */ if (dcb->state == DCB_STATE_ALLOC && dcb->fd == DCBFD_CLOSED) { dcb_final_free(dcb); return; } /*< * Stop dcb's listening and modify state accordingly. */ if (dcb->state == DCB_STATE_POLLING || dcb->state == DCB_STATE_LISTENING) { if (dcb->state == DCB_STATE_LISTENING) { LOGIF(LE, (skygw_log_write( LOGFILE_ERROR, "%lu [dcb_close] Error : Removing DCB %p but was in state %s " "which is not expected for a call to dcb_close, although it" "should be processed correctly. ", pthread_self(), dcb, STRDCBSTATE(dcb->state)))); } if ((dcb->state == DCB_STATE_POLLING && !dcb_maybe_add_persistent(dcb)) || (dcb->state == DCB_STATE_LISTENING)) { dcb_close_finish(dcb); } } spinlock_acquire(&zombiespin); if (dcb->state == DCB_STATE_NOPOLLING || dcb->state == DCB_STATE_ALLOC) { /*< * Add closing dcb to the top of the list. */ dcb->memdata.next = zombies; zombies = dcb; /*< * Set state which indicates that it has been added to zombies * list. */ dcb->state = DCB_STATE_ZOMBIE; } spinlock_release(&zombiespin); } /** * Add DCB to persistent pool if it qualifies, close otherwise * * @param dcb The DCB to go to persistent pool or be closed * @return bool - whether the DCB was added to the pool * */ static bool dcb_maybe_add_persistent(DCB *dcb) { char *user; int poolcount = -1; user = session_getUser(dcb->session); if (user && strlen(user) && dcb->server && dcb->server->persistpoolmax && !dcb->dcb_errhandle_called && !(dcb->flags & DCBF_HUNG) && (poolcount = dcb_persistent_clean_count(dcb, false)) < dcb->server->persistpoolmax) { LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_maybe_add_persistent] Adding DCB to persistent pool, user %s.\n", pthread_self(), user))); dcb->user = strdup(user); dcb->persistentstart = time(NULL); session_unlink_dcb(dcb->session, dcb); spinlock_acquire(&dcb->server->persistlock); dcb->nextpersistent = dcb->server->persistent; dcb->server->persistent = dcb; spinlock_release(&dcb->server->persistlock); atomic_add(&dcb->server->stats.n_persistent, 1); atomic_add(&dcb->server->stats.n_current, -1); return true; } else { LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_maybe_add_persistent] Not adding DCB %p to persistent pool, user %s, " "max for pool %d, error handle called %s, hung flag %s, pool count %d.\n", pthread_self(), dcb, user ? user : "", (dcb->server && dcb->server->persistpoolmax) ? dcb->server->persistpoolmax : 0, dcb->dcb_errhandle_called ? "true" : "false", (dcb->flags & DCBF_HUNG) ? "true" : "false", poolcount))); } return false; } /** * Final calls for DCB close * * @param dcb The DCB to print * */ static void dcb_close_finish(DCB *dcb) { poll_remove_dcb(dcb); /* * Return will always be 0 or function will have crashed, so we * threw away return value. */ LOGIF(LD, (skygw_log_write( LOGFILE_DEBUG, "%lu [dcb_close] Removed dcb %p in state %s from poll set.", pthread_self(), dcb, STRDCBSTATE(dcb->state)))); /** * Do a consistency check, then adjust counter if not from persistent pool */ if (dcb->server) { if (dcb->server->persistent) CHK_DCB(dcb->server->persistent); if (0 == dcb->persistentstart) atomic_add(&dcb->server->stats.n_current, -1); } /** * close protocol and router session */ if (dcb->func.close != NULL) { dcb->func.close(dcb); } /** Call possible callback for this DCB in case of close */ dcb_call_callback(dcb, DCB_REASON_CLOSE); } /** * Diagnostic to print a DCB * * @param dcb The DCB to print * */ void printDCB(DCB *dcb) { printf("DCB: %p\n", (void *)dcb); printf("\tDCB state: %s\n", gw_dcb_state2string(dcb->state)); if (dcb->remote) printf("\tConnected to: %s\n", dcb->remote); if (dcb->user) printf("\tUsername: %s\n", dcb->user); if (dcb->protoname) printf("\tProtocol: %s\n", dcb->protoname); if (dcb->writeq) printf("\tQueued write data: %d\n",gwbuf_length(dcb->writeq)); char *statusname = server_status(dcb->server); if (statusname) { printf("\tServer status: %s\n", statusname); free(statusname); } char *rolename = dcb_role_name(dcb); if (rolename) { printf("\tRole: %s\n", rolename); free(rolename); } printf("\tStatistics:\n"); printf("\t\tNo. of Reads: %d\n", dcb->stats.n_reads); printf("\t\tNo. of Writes: %d\n", dcb->stats.n_writes); printf("\t\tNo. of Buffered Writes: %d\n", dcb->stats.n_buffered); printf("\t\tNo. of Accepts: %d\n", dcb->stats.n_accepts); printf("\t\tNo. of High Water Events: %d\n", dcb->stats.n_high_water); printf("\t\tNo. of Low Water Events: %d\n", dcb->stats.n_low_water); } /** * Display an entry from the spinlock statistics data * * @param dcb The DCB to print to * @param desc Description of the statistic * @param value The statistic value */ static void spin_reporter(void *dcb, char *desc, int value) { dcb_printf((DCB *)dcb, "\t\t%-40s %d\n", desc, value); } /** * Diagnostic to print all DCB allocated in the system * */ void printAllDCBs() { DCB *dcb; spinlock_acquire(&dcbspin); dcb = allDCBs; while (dcb) { printDCB(dcb); dcb = dcb->next; } spinlock_release(&dcbspin); } /** * Diagnostic to print one DCB in the system * * @param pdcb DCB to print results to * @param dcb DCB to be printed */ void dprintOneDCB(DCB *pdcb, DCB *dcb) { dcb_printf(pdcb, "DCB: %p\n", (void *)dcb); dcb_printf(pdcb, "\tDCB state: %s\n", gw_dcb_state2string(dcb->state)); if (dcb->session && dcb->session->service) dcb_printf(pdcb, "\tService: %s\n", dcb->session->service->name); if (dcb->remote) dcb_printf(pdcb, "\tConnected to: %s\n", dcb->remote); if (dcb->user) dcb_printf(pdcb, "\tUsername: %s\n", dcb->user); if (dcb->protoname) dcb_printf(pdcb, "\tProtocol: %s\n", dcb->protoname); if (dcb->writeq) dcb_printf(pdcb, "\tQueued write data: %d\n", gwbuf_length(dcb->writeq)); char *statusname = server_status(dcb->server); if (statusname) { dcb_printf(pdcb, "\tServer status: %s\n", statusname); free(statusname); } char *rolename = dcb_role_name(dcb); if (rolename) { dcb_printf(pdcb, "\tRole: %s\n", rolename); free(rolename); } dcb_printf(pdcb, "\tStatistics:\n"); dcb_printf(pdcb, "\t\tNo. of Reads: %d\n", dcb->stats.n_reads); dcb_printf(pdcb, "\t\tNo. of Writes: %d\n", dcb->stats.n_writes); dcb_printf(pdcb, "\t\tNo. of Buffered Writes: %d\n", dcb->stats.n_buffered); dcb_printf(pdcb, "\t\tNo. of Accepts: %d\n", dcb->stats.n_accepts); dcb_printf(pdcb, "\t\tNo. of High Water Events: %d\n", dcb->stats.n_high_water); dcb_printf(pdcb, "\t\tNo. of Low Water Events: %d\n", dcb->stats.n_low_water); if (dcb->flags & DCBF_CLONE) dcb_printf(pdcb, "\t\tDCB is a clone.\n"); if (dcb->persistentstart) { char buff[20]; struct tm * timeinfo; timeinfo = localtime (&dcb->persistentstart); strftime(buff, sizeof(buff), "%b %d %H:%M:%S", timeinfo); dcb_printf(pdcb, "\t\tAdded to persistent pool: %s\n", buff); } } /** * Diagnostic to print all DCB allocated in the system * * @param pdcb DCB to print results to */ void dprintAllDCBs(DCB *pdcb) { DCB *dcb; spinlock_acquire(&dcbspin); #if SPINLOCK_PROFILE dcb_printf(pdcb, "DCB List Spinlock Statistics:\n"); spinlock_stats(&dcbspin, spin_reporter, pdcb); dcb_printf(pdcb, "Zombie Queue Lock Statistics:\n"); spinlock_stats(&zombiespin, spin_reporter, pdcb); #endif dcb = allDCBs; while (dcb) { dprintOneDCB(pdcb, dcb); dcb = dcb->next; } spinlock_release(&dcbspin); } /** * Diagnostic routine to print DCB data in a tabular form. * * @param pdcb DCB to print results to */ void dListDCBs(DCB *pdcb) { DCB *dcb; spinlock_acquire(&dcbspin); dcb = allDCBs; dcb_printf(pdcb, "Descriptor Control Blocks\n"); dcb_printf(pdcb, "------------------+----------------------------+--------------------+----------\n"); dcb_printf(pdcb, " %-16s | %-26s | %-18s | %s\n", "DCB", "State", "Service", "Remote"); dcb_printf(pdcb, "------------------+----------------------------+--------------------+----------\n"); while (dcb) { dcb_printf(pdcb, " %-16p | %-26s | %-18s | %s\n", dcb, gw_dcb_state2string(dcb->state), ((dcb->session && dcb->session->service) ? dcb->session->service->name : ""), (dcb->remote ? dcb->remote : "")); dcb = dcb->next; } dcb_printf(pdcb, "------------------+----------------------------+--------------------+----------\n\n"); spinlock_release(&dcbspin); } /** * Diagnostic routine to print client DCB data in a tabular form. * * @param pdcb DCB to print results to */ void dListClients(DCB *pdcb) { DCB *dcb; spinlock_acquire(&dcbspin); dcb = allDCBs; dcb_printf(pdcb, "Client Connections\n"); dcb_printf(pdcb, "-----------------+------------------+----------------------+------------\n"); dcb_printf(pdcb, " %-15s | %-16s | %-20s | %s\n", "Client", "DCB", "Service", "Session"); dcb_printf(pdcb, "-----------------+------------------+----------------------+------------\n"); while (dcb) { if (dcb_isclient(dcb) && dcb->dcb_role == DCB_ROLE_REQUEST_HANDLER) { dcb_printf(pdcb, " %-15s | %16p | %-20s | %10p\n", (dcb->remote ? dcb->remote : ""), dcb, (dcb->session->service ? dcb->session->service->name : ""), dcb->session); } dcb = dcb->next; } dcb_printf(pdcb, "-----------------+------------------+----------------------+------------\n\n"); spinlock_release(&dcbspin); } /** * Diagnostic to print a DCB to another DCB * * @param pdcb The DCB to which send the output * @param dcb The DCB to print */ void dprintDCB(DCB *pdcb, DCB *dcb) { dcb_printf(pdcb, "DCB: %p\n", (void *)dcb); dcb_printf(pdcb, "\tDCB state: %s\n", gw_dcb_state2string(dcb->state)); if (dcb->session && dcb->session->service) dcb_printf(pdcb, "\tService: %s\n", dcb->session->service->name); if (dcb->remote) dcb_printf(pdcb, "\tConnected to: %s\n", dcb->remote); if (dcb->user) dcb_printf(pdcb, "\tUsername: %s\n", dcb->user); if (dcb->protoname) dcb_printf(pdcb, "\tProtocol: %s\n", dcb->protoname); dcb_printf(pdcb, "\tOwning Session: %p\n", dcb->session); if (dcb->writeq) dcb_printf(pdcb, "\tQueued write data: %d\n", gwbuf_length(dcb->writeq)); if (dcb->delayq) dcb_printf(pdcb, "\tDelayed write data: %d\n", gwbuf_length(dcb->delayq)); char *statusname = server_status(dcb->server); if (statusname) { dcb_printf(pdcb, "\tServer status: %s\n", statusname); free(statusname); } char *rolename = dcb_role_name(dcb); if (rolename) { dcb_printf(pdcb, "\tRole: %s\n", rolename); free(rolename); } dcb_printf(pdcb, "\tStatistics:\n"); dcb_printf(pdcb, "\t\tNo. of Reads: %d\n", dcb->stats.n_reads); dcb_printf(pdcb, "\t\tNo. of Writes: %d\n", dcb->stats.n_writes); dcb_printf(pdcb, "\t\tNo. of Buffered Writes: %d\n", dcb->stats.n_buffered); dcb_printf(pdcb, "\t\tNo. of Accepts: %d\n", dcb->stats.n_accepts); dcb_printf(pdcb, "\t\tNo. of High Water Events: %d\n", dcb->stats.n_high_water); dcb_printf(pdcb, "\t\tNo. of Low Water Events: %d\n", dcb->stats.n_low_water); if (DCB_POLL_BUSY(dcb)) { dcb_printf(pdcb, "\t\tPending events in the queue: %x %s\n", dcb->evq.pending_events, dcb->evq.processing ? "(processing)" : ""); } if (dcb->flags & DCBF_CLONE) dcb_printf(pdcb, "\t\tDCB is a clone.\n"); #if SPINLOCK_PROFILE dcb_printf(pdcb, "\tInitlock Statistics:\n"); spinlock_stats(&dcb->dcb_initlock, spin_reporter, pdcb); dcb_printf(pdcb, "\tWrite Queue Lock Statistics:\n"); spinlock_stats(&dcb->writeqlock, spin_reporter, pdcb); dcb_printf(pdcb, "\tDelay Queue Lock Statistics:\n"); spinlock_stats(&dcb->delayqlock, spin_reporter, pdcb); dcb_printf(pdcb, "\tPollin Lock Statistics:\n"); spinlock_stats(&dcb->pollinlock, spin_reporter, pdcb); dcb_printf(pdcb, "\tPollout Lock Statistics:\n"); spinlock_stats(&dcb->polloutlock, spin_reporter, pdcb); dcb_printf(pdcb, "\tCallback Lock Statistics:\n"); spinlock_stats(&dcb->cb_lock, spin_reporter, pdcb); #endif if (dcb->persistentstart) { char buff[20]; struct tm * timeinfo; timeinfo = localtime (&dcb->persistentstart); strftime(buff, sizeof(buff), "%b %d %H:%M:%S", timeinfo); dcb_printf(pdcb, "\t\tAdded to persistent pool: %s\n", buff); } } /** * Return a string representation of a DCB state. * * @param state The DCB state * @return String representation of the state * */ const char * gw_dcb_state2string (int state) { switch(state) { case DCB_STATE_ALLOC: return "DCB Allocated"; case DCB_STATE_POLLING: return "DCB in the polling loop"; case DCB_STATE_NOPOLLING: return "DCB not in the polling loop"; case DCB_STATE_LISTENING: return "DCB for listening socket"; case DCB_STATE_DISCONNECTED: return "DCB socket closed"; case DCB_STATE_FREED: return "DCB memory could be freed"; case DCB_STATE_ZOMBIE: return "DCB Zombie"; case DCB_STATE_UNDEFINED: return "DCB undefined state"; default: return "DCB (unknown - erroneous)"; } } /** * A DCB based wrapper for printf. Allows formatting printing to * a descriptor control block. * * @param dcb Descriptor to write to * @param fmt A printf format string * @param ... Variable arguments for the print format */ void dcb_printf(DCB *dcb, const char *fmt, ...) { GWBUF *buf; va_list args; if ((buf = gwbuf_alloc(10240)) == NULL) return; va_start(args, fmt); vsnprintf(GWBUF_DATA(buf), 10240, fmt, args); va_end(args); buf->end = GWBUF_DATA(buf) + strlen(GWBUF_DATA(buf)); dcb->func.write(dcb, buf); } /** * Determine the role that a DCB plays within a session. * * @param dcb * @return Non-zero if the DCB is the client of the session */ int dcb_isclient(DCB *dcb) { if (dcb->state != DCB_STATE_LISTENING && dcb->session) { if (dcb->session->client) { return (dcb->session && dcb == dcb->session->client); } } return 0; } /** * Print hash table statistics to a DCB * * @param dcb The DCB to send the information to * @param table The hash table */ void dcb_hashtable_stats( DCB *dcb, void *table) { int total; int longest; int hashsize; total = 0; longest = 0; hashtable_get_stats(table, &hashsize, &total, &longest); dcb_printf(dcb, "Hashtable: %p, size %d\n", table, hashsize); dcb_printf(dcb, "\tNo. of entries: %d\n", total); dcb_printf(dcb, "\tAverage chain length: %.1f\n", (hashsize == 0 ? (float)hashsize : (float)total / hashsize)); dcb_printf(dcb, "\tLongest chain length: %d\n", longest); } /** * Write data to a socket through an SSL structure. The SSL structure is linked to a DCB's socket * and all communication is encrypted and done via the SSL structure. * * @param ssl The SSL structure to use for writing * @param buf Buffer to write * @param nbytes Number of bytes to write * @return Number of written bytes */ int gw_write_SSL(SSL* ssl, const void *buf, size_t nbytes) { int w = 0; int fd = SSL_get_fd(ssl); if (fd > 0) { w = SSL_write(ssl, buf, nbytes); } return w; } /** * Write data to a DCB * * @param dcb The DCB to write buffer * @param buf Buffer to write * @param nbytes Number of bytes to write * @return Number of written bytes */ int gw_write(DCB *dcb, const void *buf, size_t nbytes) { int w = 0; int fd = dcb->fd; #if defined(FAKE_CODE) if (fd > 0 && dcb_fake_write_errno[fd] != 0) { ss_dassert(dcb_fake_write_ev[fd] != 0); w = write(fd, buf, nbytes/2); /*< leave peer to read missing bytes */ if (w > 0) { w = -1; errno = dcb_fake_write_errno[fd]; } } else if (fd > 0) { w = write(fd, buf, nbytes); } #else if (fd > 0) { w = write(fd, buf, nbytes); } #endif /* FAKE_CODE */ #if defined(SS_DEBUG_MYSQL) { size_t len; uint8_t* packet = (uint8_t *)buf; char* str; /** Print only MySQL packets */ if (w > 5) { str = (char *)&packet[5]; len = packet[0]; len += 256*packet[1]; len += 256*256*packet[2]; if (strncmp(str, "insert", 6) == 0 || strncmp(str, "create", 6) == 0 || strncmp(str, "drop", 4) == 0) { ss_dassert((dcb->dcb_server_status & (SERVER_RUNNING|SERVER_MASTER|SERVER_SLAVE))==(SERVER_RUNNING|SERVER_MASTER)); } if (strncmp(str, "set autocommit", 14) == 0 && nbytes > 17) { char* s = (char *)calloc(1, nbytes+1); if (nbytes-5 > len) { size_t len2 = packet[4+len]; len2 += 256*packet[4+len+1]; len2 += 256*256*packet[4+len+2]; char* str2 = (char *)&packet[4+len+5]; snprintf(s, 5+len+len2, "long %s %s", (char *)str, (char *)str2); } else { snprintf(s, len, "%s", (char *)str); } LOGIF(LT, (skygw_log_write( LOGFILE_TRACE, "%lu [gw_write] Wrote %d bytes : %s ", pthread_self(), w, s))); free(s); } } } #endif return w; } /** * Add a callback * * Duplicate registrations are not allowed, therefore an error will be * returned if the specific function, reason and userdata triple * are already registered. * An error will also be returned if the is insufficient memeory available to * create the registration. * * @param dcb The DCB to add the callback to * @param reason The callback reason * @param callback The callback function to call * @param userdata User data to send in the call * @return Non-zero (true) if the callback was added */ int dcb_add_callback(DCB *dcb, DCB_REASON reason, int (*callback)(struct dcb *, DCB_REASON, void *), void *userdata) { DCB_CALLBACK *cb, *ptr; int rval = 1; if ((ptr = (DCB_CALLBACK *)malloc(sizeof(DCB_CALLBACK))) == NULL) { return 0; } ptr->reason = reason; ptr->cb = callback; ptr->userdata = userdata; ptr->next = NULL; spinlock_acquire(&dcb->cb_lock); cb = dcb->callbacks; if (cb == NULL) { dcb->callbacks = ptr; spinlock_release(&dcb->cb_lock); } else { while (cb) { if (cb->reason == reason && cb->cb == callback && cb->userdata == userdata) { free(ptr); spinlock_release(&dcb->cb_lock); return 0; } if (cb->next == NULL) { cb->next = ptr; break; } cb = cb->next; } spinlock_release(&dcb->cb_lock); } return rval; } /** * Remove a callback from the callback list for the DCB * * Searches down the linked list to find the callback with a matching reason, function * and userdata. * * @param dcb The DCB to add the callback to * @param reason The callback reason * @param callback The callback function to call * @param userdata User data to send in the call * @return Non-zero (true) if the callback was removed */ int dcb_remove_callback(DCB *dcb, DCB_REASON reason, int (*callback)(struct dcb *, DCB_REASON, void *), void *userdata) { DCB_CALLBACK *cb, *pcb = NULL; int rval = 0; spinlock_acquire(&dcb->cb_lock); cb = dcb->callbacks; if (cb == NULL) { rval = 0; } else { while (cb) { if (cb->reason == reason && cb->cb == callback && cb->userdata == userdata) { if (pcb != NULL) pcb->next = cb->next; else dcb->callbacks = cb->next; spinlock_release(&dcb->cb_lock); free(cb); rval = 1; break; } pcb = cb; cb = cb->next; } } if (!rval) spinlock_release(&dcb->cb_lock); return rval; } /** * Call the set of callbacks registered for a particular reason. * * @param dcb The DCB to call the callbacks regarding * @param reason The reason that has triggered the call */ static void dcb_call_callback(DCB *dcb, DCB_REASON reason) { DCB_CALLBACK *cb, *nextcb; spinlock_acquire(&dcb->cb_lock); cb = dcb->callbacks; while (cb) { if (cb->reason == reason) { nextcb = cb->next; spinlock_release(&dcb->cb_lock); LOGIF(LD, (skygw_log_write(LOGFILE_DEBUG, "%lu [dcb_call_callback] %s", pthread_self(), STRDCBREASON(reason)))); cb->cb(dcb, reason, cb->userdata); spinlock_acquire(&dcb->cb_lock); cb = nextcb; } else cb = cb->next; } spinlock_release(&dcb->cb_lock); } /** * Check the passed DCB to ensure it is in the list of allDCBS * * @param dcb The DCB to check * @return 1 if the DCB is in the list, otherwise 0 */ int dcb_isvalid(DCB *dcb) { int rval = 0; if (dcb) { spinlock_acquire(&dcbspin); rval = dcb_isvalid_nolock(dcb); spinlock_release(&dcbspin); } return rval; } /** * Find a DCB in the list of all DCB's * * @param dcb The DCB to find * @return A pointer to the DCB or NULL if not in the list */ static inline DCB * dcb_find_in_list (DCB *dcb) { DCB *ptr = NULL; if (dcb) { ptr = allDCBs; while (ptr && ptr != dcb) { ptr = ptr->next; } } return ptr; } /** * Check the passed DCB to ensure it is in the list of allDCBS. * Requires that the DCB list is already locked before call. * * @param dcb The DCB to check * @return 1 if the DCB is in the list, otherwise 0 */ static inline int dcb_isvalid_nolock(DCB *dcb) { return (dcb == dcb_find_in_list(dcb)); } /** * Get the next DCB in the list of all DCB's * * @param dcb The current DCB * @return The pointer to the next DCB or NULL if this is the last */ static DCB * dcb_get_next (DCB *dcb) { spinlock_acquire(&dcbspin); if (dcb) { dcb = dcb_isvalid_nolock(dcb) ? dcb->next : NULL; } else dcb = allDCBs; spinlock_release(&dcbspin); return dcb; } /** * Call all the callbacks on all DCB's that match the server and the reason given * * @param reason The DCB_REASON that triggers the callback */ void dcb_call_foreach(struct server* server, DCB_REASON reason) { LOGIF(LD, (skygw_log_write(LOGFILE_DEBUG, "%lu [dcb_call_foreach]", pthread_self()))); switch (reason) { case DCB_REASON_CLOSE: case DCB_REASON_DRAINED: case DCB_REASON_HIGH_WATER: case DCB_REASON_LOW_WATER: case DCB_REASON_ERROR: case DCB_REASON_HUP: case DCB_REASON_NOT_RESPONDING: { DCB *dcb; dcb = dcb_get_next(NULL); while (dcb != NULL) { if (dcb->state == DCB_STATE_POLLING && dcb->server && strcmp(dcb->server->unique_name,server->unique_name) == 0) { dcb_call_callback(dcb, DCB_REASON_NOT_RESPONDING); } dcb = dcb_get_next(dcb); } break; } default: break; } return; } /** * Null protocol write routine used for cloned dcb's. It merely consumes * buffers written on the cloned DCB and sets the DCB_REPLIED flag. * * @param dcb The descriptor control block * @param buf The buffer being written * @return Always returns a good write operation result */ static int dcb_null_write(DCB *dcb, GWBUF *buf) { while (buf) { buf = gwbuf_consume(buf, GWBUF_LENGTH(buf)); } dcb->flags |= DCBF_REPLIED; return 1; } /** * Null protocol close operation for use by cloned DCB's. * * @param dcb The DCB being closed. */ static int dcb_null_close(DCB *dcb) { return 0; } /** * Null protocol auth operation for use by cloned DCB's. * * @param dcb The DCB being closed. * @param server The server to auth against * @param session The user session * @param buf The buffer with the new auth request */ static int dcb_null_auth(DCB *dcb, SERVER *server, SESSION *session, GWBUF *buf) { return 0; } /** * Check persistent pool for expiry or excess size and count * * @param dcb The DCB being closed. * @param cleanall Boolean, if true the whole pool is cleared for the * server related to the given DCB * @return A count of the DCBs remaining in the pool */ int dcb_persistent_clean_count(DCB *dcb, bool cleanall) { int count = 0; if (dcb && dcb->server) { SERVER *server = dcb->server; DCB *previousdcb = NULL; DCB *persistentdcb, *nextdcb; DCB *disposals = NULL; CHK_SERVER(server); spinlock_acquire(&server->persistlock); persistentdcb = server->persistent; while (persistentdcb) { CHK_DCB(persistentdcb); nextdcb = persistentdcb->nextpersistent; if (cleanall || persistentdcb-> dcb_errhandle_called || count >= server->persistpoolmax || (time(NULL) - persistentdcb->persistentstart) > server->persistmaxtime) { /* Remove from persistent pool */ if (previousdcb) { previousdcb->nextpersistent = nextdcb; } else { server->persistent = nextdcb; } /* Add removed DCBs to disposal list for processing outside spinlock */ persistentdcb->nextpersistent = disposals; disposals = persistentdcb; atomic_add(&server->stats.n_persistent, -1); } else { count++; previousdcb = persistentdcb; } persistentdcb = nextdcb; } server->persistmax = MAX(server->persistmax, count); spinlock_release(&server->persistlock); /** Call possible callback for this DCB in case of close */ while (disposals) { nextdcb = disposals->nextpersistent; dcb_close_finish(disposals); dcb_close(disposals); disposals = nextdcb; } } return count; } /** * Return DCB counts optionally filtered by usage * * @param usage The usage of the DCB * @return A count of DCBs in the desired state */ int dcb_count_by_usage(DCB_USAGE usage) { int rval = 0; DCB *ptr; spinlock_acquire(&dcbspin); ptr = allDCBs; while (ptr) { switch (usage) { case DCB_USAGE_CLIENT: if (dcb_isclient(ptr)) rval++; break; case DCB_USAGE_LISTENER: if (ptr->state == DCB_STATE_LISTENING) rval++; break; case DCB_USAGE_BACKEND: if (dcb_isclient(ptr) == 0 && ptr->dcb_role == DCB_ROLE_REQUEST_HANDLER) rval++; break; case DCB_USAGE_INTERNAL: if (ptr->dcb_role == DCB_ROLE_REQUEST_HANDLER) rval++; break; case DCB_USAGE_ZOMBIE: if (DCB_ISZOMBIE(ptr)) rval++; break; case DCB_USAGE_ALL: rval++; break; } ptr = ptr->next; } spinlock_release(&dcbspin); return rval; } /** * Create the SSL structure for this DCB. * This function creates the SSL structure for the given SSL context. This context * should be the service's context * @param dcb * @param context * @return */ int dcb_create_SSL(DCB* dcb) { if(serviceInitSSL(dcb->service) != 0) { return -1; } if((dcb->ssl = SSL_new(dcb->service->ctx)) == NULL) { skygw_log_write(LE,"Error: Failed to initialize SSL for connection."); return -1; } if(SSL_set_fd(dcb->ssl,dcb->fd) == 0) { skygw_log_write(LE,"Error: Failed to set file descriptor for SSL connection."); return -1; } return 0; } /** * Accept a SSL connection and do the SSL authentication handshake. * This function accepts a client connection to a DCB. It assumes that the SSL * structure has the underlying method of communication set and this method is ready * for usage. It then proceeds with the SSL handshake and stops only if an error * occurs or the client has not yet written enough data to complete the handshake. * @param dcb DCB which should accept the SSL connection * @return 1 if the handshake was successfully completed, 0 if the handshake is * still ongoing and another call to dcb_SSL_accept should be made or -1 if an * error occurred during the handshake and the connection should be terminated. */ int dcb_accept_SSL(DCB* dcb) { int rval = 0,ssl_rval,errnum = 0,fd,b = 0,pending; char errbuf[140]; fd = dcb->fd; do { ssl_rval = SSL_accept(dcb->ssl); LOGIF(LD,(skygw_log_write_flush(LD,"[dcb_accept_SSL] SSL_accept %d, error %d", ssl_rval,errnum))); switch(ssl_rval) { case 0: errnum = SSL_get_error(dcb->ssl,ssl_rval); skygw_log_write(LE,"Error: SSL authentication failed (SSL error %d):", dcb, dcb->remote, errnum); if(errnum == SSL_ERROR_SSL || errnum == SSL_ERROR_SYSCALL) { while((errnum = ERR_get_error()) != 0) { ERR_error_string_n(errnum,errbuf,140); skygw_log_write(LE,"%s",errbuf); } } rval = -1; break; case 1: rval = 1; LOGIF(LD,(skygw_log_write_flush(LD,"[dcb_accept_SSL] SSL_accept done for %s", dcb->remote))); return rval; case -1: errnum = SSL_get_error(dcb->ssl,ssl_rval); if(errnum == SSL_ERROR_WANT_READ || errnum == SSL_ERROR_WANT_WRITE) { /** Not all of the data has been read. Go back to the poll queue and wait for more.*/ rval = 0; LOGIF(LD,(skygw_log_write_flush(LD,"[dcb_accept_SSL] SSL_accept ongoing for %s", dcb->remote))); return rval; } else { rval = -1; skygw_log_write(LE, "Error: Fatal error in SSL_accept for %s: (SSL version: %s SSL error code: %d)", dcb->remote, SSL_get_version(dcb->ssl), errnum); if(errnum == SSL_ERROR_SSL || errnum == SSL_ERROR_SYSCALL) { while((errnum = ERR_get_error()) != 0) { ERR_error_string_n(errnum,errbuf,140); skygw_log_write(LE, "%s", errbuf); } } } break; default: skygw_log_write_flush(LE, "Error: Fatal library error in SSL_accept, returned value was %d.", ssl_rval); rval = -1; break; } ioctl(fd,FIONREAD,&b); pending = SSL_pending(dcb->ssl); #ifdef SS_DEBUG skygw_log_write_flush(LD,"[dcb_accept_SSL] fd %d: %d bytes, %d pending",fd,b,pending); #endif }while((b > 0 || pending > 0) && rval != -1); return rval; } /** * Initiate an SSL client connection to a server * * This functions starts an SSL client connection to a server which is expecting * an SSL handshake. The DCB should already have a TCP connection to the server and * this connection should be in a state that expects an SSL handshake. * @param dcb DCB to connect * @return 1 on success, -1 on error and 0 if the SSL handshake is still ongoing */ int dcb_connect_SSL(DCB* dcb) { int rval,errnum; char errbuf[140]; rval = SSL_connect(dcb->ssl); switch(rval) { case 0: errnum = SSL_get_error(dcb->ssl,rval); LOGIF(LD,(skygw_log_write_flush(LD,"SSL_connect shutdown for %s@%s", dcb->user, dcb->remote))); return -1; break; case 1: rval = 1; LOGIF(LD,(skygw_log_write_flush(LD,"SSL_connect done for %s@%s", dcb->user, dcb->remote))); return rval; case -1: errnum = SSL_get_error(dcb->ssl,rval); if(errnum == SSL_ERROR_WANT_READ || errnum == SSL_ERROR_WANT_WRITE) { /** Not all of the data has been read. Go back to the poll queue and wait for more.*/ rval = 0; LOGIF(LD,(skygw_log_write_flush(LD,"SSL_connect ongoing for %s@%s", dcb->user, dcb->remote))); } else { rval = -1; ERR_error_string_n(errnum,errbuf,140); skygw_log_write_flush(LE, "Error: Fatal error in SSL_accept for %s@%s: (SSL error code: %d) %s", dcb->user, dcb->remote, errnum, errbuf); } break; default: skygw_log_write_flush(LE, "Error: Fatal error in SSL_connect, returned value was %d.", rval); break; } return rval; } /** * Convert a DCB role to a string, the returned * string has been malloc'd and must be free'd by the caller * * @param DCB The DCB to return the role of * @return A string representation of the DCB role */ char * dcb_role_name(DCB *dcb) { char *name = NULL; if (NULL != (name = (char *)malloc(64))) { name[0] = 0; if (DCB_ROLE_SERVICE_LISTENER == dcb->dcb_role) strcat(name, "Service Listener"); else if (DCB_ROLE_REQUEST_HANDLER == dcb->dcb_role) strcat(name, "Request Handler"); else if (DCB_ROLE_INTERNAL == dcb->dcb_role) strcat(name, "Internal"); else strcat(name, "Unknown"); } return name; }