/* Unix SMB/CIFS implementation. SMB client transport context management functions Copyright (C) Andrew Tridgell 1994-2003 Copyright (C) James Myers 2003 This program 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; either version 2 of the License, or (at your option) any later version. 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., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include "includes.h" #include "libcli/raw/libcliraw.h" #include "system/time.h" #include "dlinklist.h" static void smbcli_transport_process_recv(struct smbcli_transport *transport); static void smbcli_transport_process_send(struct smbcli_transport *transport); /* an event has happened on the socket */ static void smbcli_transport_event_handler(struct event_context *ev, struct fd_event *fde, time_t t, uint16_t flags) { struct smbcli_transport *transport = fde->private; if (flags & EVENT_FD_READ) { smbcli_transport_process_recv(transport); } if (flags & EVENT_FD_WRITE) { smbcli_transport_process_send(transport); } } /* destroy a transport */ static int transport_destructor(void *ptr) { struct smbcli_transport *transport = ptr; smbcli_transport_dead(transport); event_remove_fd(transport->event.ctx, transport->event.fde); event_remove_timed(transport->event.ctx, transport->event.te); return 0; } /* create a transport structure based on an established socket */ struct smbcli_transport *smbcli_transport_init(struct smbcli_socket *sock) { struct smbcli_transport *transport; struct fd_event fde; transport = talloc_p(sock, struct smbcli_transport); if (!transport) return NULL; ZERO_STRUCTP(transport); transport->event.ctx = event_context_init(transport); if (transport->event.ctx == NULL) { talloc_free(transport); return NULL; } transport->socket = talloc_reference(transport, sock); transport->negotiate.protocol = PROTOCOL_NT1; transport->options.use_spnego = lp_use_spnego(); transport->options.max_xmit = lp_max_xmit(); transport->options.max_mux = lp_maxmux(); transport->negotiate.max_xmit = transport->options.max_xmit; smbcli_init_signing(transport); ZERO_STRUCT(transport->called); fde.fd = socket_get_fd(sock->sock); fde.flags = EVENT_FD_READ; fde.handler = smbcli_transport_event_handler; fde.private = transport; fde.ref_count = 1; transport->event.fde = event_add_fd(transport->event.ctx, &fde); talloc_set_destructor(transport, transport_destructor); return transport; } /* mark the transport as dead */ void smbcli_transport_dead(struct smbcli_transport *transport) { smbcli_sock_dead(transport->socket); /* all pending sends become errors */ while (transport->pending_send) { struct smbcli_request *req = transport->pending_send; req->state = SMBCLI_REQUEST_ERROR; req->status = NT_STATUS_NET_WRITE_FAULT; DLIST_REMOVE(transport->pending_send, req); if (req->async.fn) { req->async.fn(req); } } /* as do all pending receives */ while (transport->pending_recv) { struct smbcli_request *req = transport->pending_recv; req->state = SMBCLI_REQUEST_ERROR; req->status = NT_STATUS_NET_WRITE_FAULT; DLIST_REMOVE(transport->pending_recv, req); if (req->async.fn) { req->async.fn(req); } } } /* enable select for write on a transport */ static void smbcli_transport_write_enable(struct smbcli_transport *transport) { transport->event.fde->flags |= EVENT_FD_WRITE; } /* disable select for write on a transport */ static void smbcli_transport_write_disable(struct smbcli_transport *transport) { transport->event.fde->flags &= ~EVENT_FD_WRITE; } /**************************************************************************** send a session request (if appropriate) ****************************************************************************/ BOOL smbcli_transport_connect(struct smbcli_transport *transport, struct nmb_name *calling, struct nmb_name *called) { char *p; int len = NBT_HDR_SIZE; struct smbcli_request *req; if (called) { transport->called = *called; } /* 445 doesn't have session request */ if (transport->socket->port == 445) { return True; } /* allocate output buffer */ req = smbcli_request_setup_nonsmb(transport, NBT_HDR_SIZE + 2*nbt_mangled_name_len()); /* put in the destination name */ p = req->out.buffer + NBT_HDR_SIZE; name_mangle(called->name, p, called->name_type); len += name_len(p); /* and my name */ p = req->out.buffer+len; name_mangle(calling->name, p, calling->name_type); len += name_len(p); _smb_setlen(req->out.buffer,len-4); SCVAL(req->out.buffer,0,0x81); if (!smbcli_request_send(req) || !smbcli_request_receive(req)) { smbcli_request_destroy(req); return False; } if (CVAL(req->in.buffer,0) != 0x82) { transport->error.etype = ETYPE_NBT; transport->error.e.nbt_error = CVAL(req->in.buffer,4); smbcli_request_destroy(req); return False; } smbcli_request_destroy(req); return True; } /**************************************************************************** get next mid in sequence ****************************************************************************/ uint16_t smbcli_transport_next_mid(struct smbcli_transport *transport) { uint16_t mid; struct smbcli_request *req; mid = transport->next_mid; again: /* now check to see if this mid is being used by one of the pending requests. This is quite efficient because the list is usually very short */ /* the zero mid is reserved for requests that don't have a mid */ if (mid == 0) mid = 1; for (req=transport->pending_recv; req; req=req->next) { if (req->mid == mid) { mid++; goto again; } } transport->next_mid = mid+1; return mid; } static void idle_handler(struct event_context *ev, struct timed_event *te, time_t t) { struct smbcli_transport *transport = te->private; te->next_event = t + transport->idle.period; transport->idle.func(transport, transport->idle.private); } /* setup the idle handler for a transport the period is in seconds */ void smbcli_transport_idle_handler(struct smbcli_transport *transport, void (*idle_func)(struct smbcli_transport *, void *), uint_t period, void *private) { struct timed_event te; transport->idle.func = idle_func; transport->idle.private = private; transport->idle.period = period; if (transport->event.te != NULL) { event_remove_timed(transport->event.ctx, transport->event.te); } te.next_event = time(NULL) + period; te.handler = idle_handler; te.private = transport; transport->event.te = event_add_timed(transport->event.ctx, &te); } /* process some pending sends */ static void smbcli_transport_process_send(struct smbcli_transport *transport) { while (transport->pending_send) { struct smbcli_request *req = transport->pending_send; ssize_t ret; ret = smbcli_sock_write(transport->socket, req->out.buffer, req->out.size); if (ret == -1) { if (errno == EAGAIN || errno == EINTR) { return; } smbcli_transport_dead(transport); return; } req->out.buffer += ret; req->out.size -= ret; if (req->out.size == 0) { DLIST_REMOVE(transport->pending_send, req); if (req->one_way_request) { req->state = SMBCLI_REQUEST_DONE; smbcli_request_destroy(req); } else { req->state = SMBCLI_REQUEST_RECV; DLIST_ADD(transport->pending_recv, req); } } } /* we're out of requests to send, so don't wait for write events any more */ smbcli_transport_write_disable(transport); } /* we have a full request in our receive buffer - match it to a pending request and process */ static void smbcli_transport_finish_recv(struct smbcli_transport *transport) { uint8_t *buffer, *hdr, *vwv; int len; uint16_t wct=0, mid = 0; struct smbcli_request *req; buffer = transport->recv_buffer.buffer; len = transport->recv_buffer.req_size; ZERO_STRUCT(transport->recv_buffer); hdr = buffer+NBT_HDR_SIZE; vwv = hdr + HDR_VWV; /* see if it could be an oplock break request */ if (handle_oplock_break(transport, len, hdr, vwv)) { talloc_free(buffer); return; } /* at this point we need to check for a readbraw reply, as these can be any length */ if (transport->readbraw_pending) { transport->readbraw_pending = 0; /* it must match the first entry in the pending queue as the client is not allowed to have outstanding readbraw requests */ req = transport->pending_recv; if (!req) goto error; req->in.buffer = buffer; talloc_steal(req, buffer); req->in.size = len; req->in.allocated = req->in.size; goto async; } if (len >= MIN_SMB_SIZE) { /* extract the mid for matching to pending requests */ mid = SVAL(hdr, HDR_MID); wct = CVAL(hdr, HDR_WCT); } /* match the incoming request against the list of pending requests */ for (req=transport->pending_recv; req; req=req->next) { if (req->mid == mid) break; } if (!req) { DEBUG(1,("Discarding unmatched reply with mid %d op %d\n", mid, CVAL(hdr, HDR_COM))); goto error; } /* fill in the 'in' portion of the matching request */ req->in.buffer = buffer; talloc_steal(req, buffer); req->in.size = len; req->in.allocated = req->in.size; /* handle NBT session replies */ if (req->in.size >= 4 && req->in.buffer[0] != 0) { req->status = NT_STATUS_OK; goto async; } /* handle non-SMB replies */ if (req->in.size < NBT_HDR_SIZE + MIN_SMB_SIZE) { req->state = SMBCLI_REQUEST_ERROR; goto error; } if (req->in.size < NBT_HDR_SIZE + MIN_SMB_SIZE + VWV(wct)) { DEBUG(2,("bad reply size for mid %d\n", mid)); req->status = NT_STATUS_UNSUCCESSFUL; req->state = SMBCLI_REQUEST_ERROR; goto error; } req->in.hdr = hdr; req->in.vwv = vwv; req->in.wct = wct; if (req->in.size >= NBT_HDR_SIZE + MIN_SMB_SIZE + VWV(wct)) { req->in.data = req->in.vwv + VWV(wct) + 2; req->in.data_size = SVAL(req->in.vwv, VWV(wct)); if (req->in.size < NBT_HDR_SIZE + MIN_SMB_SIZE + VWV(wct) + req->in.data_size) { DEBUG(3,("bad data size for mid %d\n", mid)); /* blergh - w2k3 gives a bogus data size values in some openX replies */ req->in.data_size = req->in.size - (NBT_HDR_SIZE + MIN_SMB_SIZE + VWV(wct)); } } req->in.ptr = req->in.data; req->flags2 = SVAL(req->in.hdr, HDR_FLG2); if (!(req->flags2 & FLAGS2_32_BIT_ERROR_CODES)) { transport->error.etype = ETYPE_DOS; transport->error.e.dos.eclass = CVAL(req->in.hdr,HDR_RCLS); transport->error.e.dos.ecode = SVAL(req->in.hdr,HDR_ERR); req->status = dos_to_ntstatus(transport->error.e.dos.eclass, transport->error.e.dos.ecode); } else { transport->error.etype = ETYPE_NT; transport->error.e.nt_status = NT_STATUS(IVAL(req->in.hdr, HDR_RCLS)); req->status = transport->error.e.nt_status; } if (!smbcli_request_check_sign_mac(req)) { transport->error.etype = ETYPE_SOCKET; transport->error.e.socket_error = SOCKET_READ_BAD_SIG; req->state = SMBCLI_REQUEST_ERROR; goto error; }; async: /* if this request has an async handler then call that to notify that the reply has been received. This might destroy the request so it must happen last */ DLIST_REMOVE(transport->pending_recv, req); req->state = SMBCLI_REQUEST_DONE; if (req->async.fn) { req->async.fn(req); } return; error: if (req) { DLIST_REMOVE(transport->pending_recv, req); req->state = SMBCLI_REQUEST_ERROR; } } /* process some pending receives */ static void smbcli_transport_process_recv(struct smbcli_transport *transport) { /* a incoming packet goes through 2 stages - first we read the 4 byte header, which tells us how much more is coming. Then we read the rest */ if (transport->recv_buffer.received < NBT_HDR_SIZE) { ssize_t ret; ret = smbcli_sock_read(transport->socket, transport->recv_buffer.header + transport->recv_buffer.received, NBT_HDR_SIZE - transport->recv_buffer.received); if (ret == -1) { smbcli_transport_dead(transport); return; } transport->recv_buffer.received += ret; if (transport->recv_buffer.received == NBT_HDR_SIZE) { /* we've got a full header */ transport->recv_buffer.req_size = smb_len(transport->recv_buffer.header) + NBT_HDR_SIZE; transport->recv_buffer.buffer = talloc(transport, NBT_HDR_SIZE+transport->recv_buffer.req_size); if (transport->recv_buffer.buffer == NULL) { smbcli_transport_dead(transport); return; } memcpy(transport->recv_buffer.buffer, transport->recv_buffer.header, NBT_HDR_SIZE); } } if (transport->recv_buffer.received < transport->recv_buffer.req_size) { ssize_t ret; ret = smbcli_sock_read(transport->socket, transport->recv_buffer.buffer + transport->recv_buffer.received, transport->recv_buffer.req_size - transport->recv_buffer.received); if (ret == -1) { smbcli_transport_dead(transport); return; } transport->recv_buffer.received += ret; } if (transport->recv_buffer.received != 0 && transport->recv_buffer.received == transport->recv_buffer.req_size) { smbcli_transport_finish_recv(transport); } } /* process some read/write requests that are pending return False if the socket is dead */ BOOL smbcli_transport_process(struct smbcli_transport *transport) { smbcli_transport_process_send(transport); smbcli_transport_process_recv(transport); if (transport->socket->sock == NULL) { return False; } return True; } /* put a request into the send queue */ void smbcli_transport_send(struct smbcli_request *req) { /* check if the transport is dead */ if (req->transport->socket->sock == NULL) { req->state = SMBCLI_REQUEST_ERROR; req->status = NT_STATUS_NET_WRITE_FAULT; return; } /* put it on the outgoing socket queue */ req->state = SMBCLI_REQUEST_SEND; DLIST_ADD_END(req->transport->pending_send, req, struct smbcli_request *); /* make sure we look for write events */ smbcli_transport_write_enable(req->transport); }