/* Unix SMB/CIFS implementation. Core SMB2 server Copyright (C) Stefan Metzmacher 2009 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 3 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, see <http://www.gnu.org/licenses/>. */ #include "includes.h" #include "system/filesys.h" #include "smbd/smbd.h" #include "smbd/globals.h" #include "../libcli/smb/smb_common.h" #include "libcli/security/security.h" #include "../lib/util/tevent_ntstatus.h" #include "rpc_server/srv_pipe_hnd.h" static struct tevent_req *smbd_smb2_read_send(TALLOC_CTX *mem_ctx, struct tevent_context *ev, struct smbd_smb2_request *smb2req, uint32_t in_smbpid, uint64_t in_file_id_volatile, uint32_t in_length, uint64_t in_offset, uint32_t in_minimum, uint32_t in_remaining); static NTSTATUS smbd_smb2_read_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx, DATA_BLOB *out_data, uint32_t *out_remaining); static void smbd_smb2_request_read_done(struct tevent_req *subreq); NTSTATUS smbd_smb2_request_process_read(struct smbd_smb2_request *req) { NTSTATUS status; const uint8_t *inhdr; const uint8_t *inbody; int i = req->current_idx; uint32_t in_smbpid; uint32_t in_length; uint64_t in_offset; uint64_t in_file_id_persistent; uint64_t in_file_id_volatile; uint32_t in_minimum_count; uint32_t in_remaining_bytes; struct tevent_req *subreq; status = smbd_smb2_request_verify_sizes(req, 0x31); if (!NT_STATUS_IS_OK(status)) { return smbd_smb2_request_error(req, status); } inhdr = (const uint8_t *)req->in.vector[i+0].iov_base; inbody = (const uint8_t *)req->in.vector[i+1].iov_base; in_smbpid = IVAL(inhdr, SMB2_HDR_PID); in_length = IVAL(inbody, 0x04); in_offset = BVAL(inbody, 0x08); in_file_id_persistent = BVAL(inbody, 0x10); in_file_id_volatile = BVAL(inbody, 0x18); in_minimum_count = IVAL(inbody, 0x20); in_remaining_bytes = IVAL(inbody, 0x28); /* check the max read size */ if (in_length > req->sconn->smb2.max_read) { DEBUG(0,("here:%s: 0x%08X: 0x%08X\n", __location__, in_length, req->sconn->smb2.max_read)); return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER); } status = smbd_smb2_request_verify_creditcharge(req, in_length); if (!NT_STATUS_IS_OK(status)) { return smbd_smb2_request_error(req, status); } if (req->compat_chain_fsp) { /* skip check */ } else if (in_file_id_persistent != in_file_id_volatile) { return smbd_smb2_request_error(req, NT_STATUS_FILE_CLOSED); } subreq = smbd_smb2_read_send(req, req->sconn->ev_ctx, req, in_smbpid, in_file_id_volatile, in_length, in_offset, in_minimum_count, in_remaining_bytes); if (subreq == NULL) { return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY); } tevent_req_set_callback(subreq, smbd_smb2_request_read_done, req); return smbd_smb2_request_pending_queue(req, subreq, 500); } static void smbd_smb2_request_read_done(struct tevent_req *subreq) { struct smbd_smb2_request *req = tevent_req_callback_data(subreq, struct smbd_smb2_request); DATA_BLOB outbody; DATA_BLOB outdyn; uint8_t out_data_offset; DATA_BLOB out_data_buffer = data_blob_null; uint32_t out_data_remaining = 0; NTSTATUS status; NTSTATUS error; /* transport error */ status = smbd_smb2_read_recv(subreq, req, &out_data_buffer, &out_data_remaining); TALLOC_FREE(subreq); if (!NT_STATUS_IS_OK(status)) { error = smbd_smb2_request_error(req, status); if (!NT_STATUS_IS_OK(error)) { smbd_server_connection_terminate(req->sconn, nt_errstr(error)); return; } return; } out_data_offset = SMB2_HDR_BODY + 0x10; outbody = data_blob_talloc(req->out.vector, NULL, 0x10); if (outbody.data == NULL) { error = smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY); if (!NT_STATUS_IS_OK(error)) { smbd_server_connection_terminate(req->sconn, nt_errstr(error)); return; } return; } SSVAL(outbody.data, 0x00, 0x10 + 1); /* struct size */ SCVAL(outbody.data, 0x02, out_data_offset); /* data offset */ SCVAL(outbody.data, 0x03, 0); /* reserved */ SIVAL(outbody.data, 0x04, out_data_buffer.length); /* data length */ SIVAL(outbody.data, 0x08, out_data_remaining); /* data remaining */ SIVAL(outbody.data, 0x0C, 0); /* reserved */ outdyn = out_data_buffer; error = smbd_smb2_request_done(req, outbody, &outdyn); if (!NT_STATUS_IS_OK(error)) { smbd_server_connection_terminate(req->sconn, nt_errstr(error)); return; } } struct smbd_smb2_read_state { struct smbd_smb2_request *smb2req; struct smb_request *smbreq; files_struct *fsp; uint64_t in_file_id_volatile; uint32_t in_length; uint64_t in_offset; uint32_t in_minimum; DATA_BLOB out_data; uint32_t out_remaining; }; /* struct smbd_smb2_read_state destructor. Send the SMB2_READ data. */ static int smb2_sendfile_send_data(struct smbd_smb2_read_state *state) { struct lock_struct lock; uint32_t in_length = state->in_length; uint64_t in_offset = state->in_offset; files_struct *fsp = state->fsp; ssize_t nread; nread = SMB_VFS_SENDFILE(fsp->conn->sconn->sock, fsp, NULL, in_offset, in_length); DEBUG(10,("smb2_sendfile_send_data: SMB_VFS_SENDFILE returned %d on file %s\n", (int)nread, fsp_str_dbg(fsp) )); if (nread == -1) { if (errno == ENOSYS || errno == EINTR) { /* * Special hack for broken systems with no working * sendfile. Fake this up by doing read/write calls. */ set_use_sendfile(SNUM(fsp->conn), false); nread = fake_sendfile(fsp, in_offset, in_length); if (nread == -1) { DEBUG(0,("smb2_sendfile_send_data: " "fake_sendfile failed for " "file %s (%s).\n", fsp_str_dbg(fsp), strerror(errno))); exit_server_cleanly("smb2_sendfile_send_data: " "fake_sendfile failed"); } goto out; } DEBUG(0,("smb2_sendfile_send_data: sendfile failed for file " "%s (%s). Terminating\n", fsp_str_dbg(fsp), strerror(errno))); exit_server_cleanly("smb2_sendfile_send_data: sendfile failed"); } else if (nread == 0) { /* * Some sendfile implementations return 0 to indicate * that there was a short read, but nothing was * actually written to the socket. In this case, * fallback to the normal read path so the header gets * the correct byte count. */ DEBUG(3, ("send_file_readX: sendfile sent zero bytes " "falling back to the normal read: %s\n", fsp_str_dbg(fsp))); nread = fake_sendfile(fsp, in_offset, in_length); if (nread == -1) { DEBUG(0,("smb2_sendfile_send_data: " "fake_sendfile failed for file " "%s (%s). Terminating\n", fsp_str_dbg(fsp), strerror(errno))); exit_server_cleanly("smb2_sendfile_send_data: " "fake_sendfile failed"); } } out: if (nread < in_length) { sendfile_short_send(fsp, nread, 0, in_length); } init_strict_lock_struct(fsp, state->in_file_id_volatile, in_offset, in_length, READ_LOCK, &lock); SMB_VFS_STRICT_UNLOCK(fsp->conn, fsp, &lock); return 0; } static NTSTATUS schedule_smb2_sendfile_read(struct smbd_smb2_request *smb2req, struct smbd_smb2_read_state *state) { struct smbd_smb2_read_state *state_copy = NULL; files_struct *fsp = state->fsp; /* * We cannot use sendfile if... * We were not configured to do so OR * Signing is active OR * This is a compound SMB2 operation OR * fsp is a STREAM file OR * We're using a write cache OR * It's not a regular file OR * Requested offset is greater than file size OR * there's not enough data in the file. * Phew :-). Luckily this means most * reads on most normal files. JRA. */ if (!lp__use_sendfile(SNUM(fsp->conn)) || smb2req->do_signing || smb2req->in.vector_count != 4 || (fsp->base_fsp != NULL) || (fsp->wcp != NULL) || (!S_ISREG(fsp->fsp_name->st.st_ex_mode)) || (state->in_offset >= fsp->fsp_name->st.st_ex_size) || (fsp->fsp_name->st.st_ex_size < state->in_offset + state->in_length)) { return NT_STATUS_RETRY; } /* We've already checked there's this amount of data to read. */ state->out_data.length = state->in_length; state->out_remaining = 0; /* Make a copy of state attached to the smb2req. Attach the destructor here as this will trigger the sendfile call when the request is destroyed. */ state_copy = talloc(smb2req, struct smbd_smb2_read_state); if (!state_copy) { return NT_STATUS_NO_MEMORY; } *state_copy = *state; talloc_set_destructor(state_copy, smb2_sendfile_send_data); return NT_STATUS_OK; } static void smbd_smb2_read_pipe_done(struct tevent_req *subreq); /******************************************************************* Common read complete processing function for both synchronous and asynchronous reads. *******************************************************************/ NTSTATUS smb2_read_complete(struct tevent_req *req, ssize_t nread, int err) { struct smbd_smb2_read_state *state = tevent_req_data(req, struct smbd_smb2_read_state); files_struct *fsp = state->fsp; if (nread < 0) { NTSTATUS status = map_nt_error_from_unix(err); DEBUG( 3,( "smb2_read_complete: file %s nread = %d. " "Error = %s (NTSTATUS %s)\n", fsp_str_dbg(fsp), (int)nread, strerror(err), nt_errstr(status))); return status; } if (nread == 0 && state->in_length != 0) { DEBUG(5,("smb2_read_complete: read_file[%s] end of file\n", fsp_str_dbg(fsp))); return NT_STATUS_END_OF_FILE; } if (nread < state->in_minimum) { DEBUG(5,("smb2_read_complete: read_file[%s] read less %d than " "minimum requested %u. Returning end of file\n", fsp_str_dbg(fsp), (int)nread, (unsigned int)state->in_minimum)); return NT_STATUS_END_OF_FILE; } DEBUG(3,("smbd_smb2_read: fnum=[%d/%s] length=%lu offset=%lu read=%lu\n", fsp->fnum, fsp_str_dbg(fsp), (unsigned long)state->in_length, (unsigned long)state->in_offset, (unsigned long)nread)); state->out_data.length = nread; state->out_remaining = 0; return NT_STATUS_OK; } static bool smbd_smb2_read_cancel(struct tevent_req *req) { struct smbd_smb2_read_state *state = tevent_req_data(req, struct smbd_smb2_read_state); state->smb2req->cancelled = true; return cancel_smb2_aio(state->smbreq); } static struct tevent_req *smbd_smb2_read_send(TALLOC_CTX *mem_ctx, struct tevent_context *ev, struct smbd_smb2_request *smb2req, uint32_t in_smbpid, uint64_t in_file_id_volatile, uint32_t in_length, uint64_t in_offset, uint32_t in_minimum, uint32_t in_remaining) { NTSTATUS status; struct tevent_req *req = NULL; struct smbd_smb2_read_state *state = NULL; struct smb_request *smbreq = NULL; connection_struct *conn = smb2req->tcon->compat_conn; files_struct *fsp = NULL; ssize_t nread = -1; struct lock_struct lock; int saved_errno; req = tevent_req_create(mem_ctx, &state, struct smbd_smb2_read_state); if (req == NULL) { return NULL; } state->smb2req = smb2req; state->in_length = in_length; state->in_offset = in_offset; state->in_minimum = in_minimum; state->out_data = data_blob_null; state->out_remaining = 0; DEBUG(10,("smbd_smb2_read: file_id[0x%016llX]\n", (unsigned long long)in_file_id_volatile)); smbreq = smbd_smb2_fake_smb_request(smb2req); if (tevent_req_nomem(smbreq, req)) { return tevent_req_post(req, ev); } state->smbreq = smbreq; fsp = file_fsp(smbreq, (uint16_t)in_file_id_volatile); if (fsp == NULL) { tevent_req_nterror(req, NT_STATUS_FILE_CLOSED); return tevent_req_post(req, ev); } if (conn != fsp->conn) { tevent_req_nterror(req, NT_STATUS_FILE_CLOSED); return tevent_req_post(req, ev); } if (smb2req->session->vuid != fsp->vuid) { tevent_req_nterror(req, NT_STATUS_FILE_CLOSED); return tevent_req_post(req, ev); } if (fsp->is_directory) { tevent_req_nterror(req, NT_STATUS_INVALID_DEVICE_REQUEST); return tevent_req_post(req, ev); } state->fsp = fsp; state->in_file_id_volatile = in_file_id_volatile; if (IS_IPC(smbreq->conn)) { struct tevent_req *subreq = NULL; state->out_data = data_blob_talloc(state, NULL, in_length); if (in_length > 0 && tevent_req_nomem(state->out_data.data, req)) { return tevent_req_post(req, ev); } if (!fsp_is_np(fsp)) { tevent_req_nterror(req, NT_STATUS_FILE_CLOSED); return tevent_req_post(req, ev); } subreq = np_read_send(state, ev, fsp->fake_file_handle, state->out_data.data, state->out_data.length); if (tevent_req_nomem(subreq, req)) { return tevent_req_post(req, ev); } tevent_req_set_callback(subreq, smbd_smb2_read_pipe_done, req); return req; } if (!CHECK_READ(fsp, smbreq)) { tevent_req_nterror(req, NT_STATUS_ACCESS_DENIED); return tevent_req_post(req, ev); } status = schedule_smb2_aio_read(fsp->conn, smbreq, fsp, state, &state->out_data, (SMB_OFF_T)in_offset, (size_t)in_length); if (NT_STATUS_IS_OK(status)) { /* * Doing an async read, allow this * request to be canceled */ tevent_req_set_cancel_fn(req, smbd_smb2_read_cancel); return req; } if (!NT_STATUS_EQUAL(status, NT_STATUS_RETRY)) { /* Real error in setting up aio. Fail. */ tevent_req_nterror(req, NT_STATUS_FILE_CLOSED); return tevent_req_post(req, ev); } /* Fallback to synchronous. */ init_strict_lock_struct(fsp, in_file_id_volatile, in_offset, in_length, READ_LOCK, &lock); if (!SMB_VFS_STRICT_LOCK(conn, fsp, &lock)) { tevent_req_nterror(req, NT_STATUS_FILE_LOCK_CONFLICT); return tevent_req_post(req, ev); } /* Try sendfile in preference. */ status = schedule_smb2_sendfile_read(smb2req, state); if (NT_STATUS_IS_OK(status)) { tevent_req_done(req); return tevent_req_post(req, ev); } else { if (!NT_STATUS_EQUAL(status, NT_STATUS_RETRY)) { SMB_VFS_STRICT_UNLOCK(conn, fsp, &lock); tevent_req_nterror(req, status); return tevent_req_post(req, ev); } } /* Ok, read into memory. Allocate the out buffer. */ state->out_data = data_blob_talloc(state, NULL, in_length); if (in_length > 0 && tevent_req_nomem(state->out_data.data, req)) { SMB_VFS_STRICT_UNLOCK(conn, fsp, &lock); return tevent_req_post(req, ev); } nread = read_file(fsp, (char *)state->out_data.data, in_offset, in_length); saved_errno = errno; SMB_VFS_STRICT_UNLOCK(conn, fsp, &lock); DEBUG(10,("smbd_smb2_read: file %s handle [0x%016llX] offset=%llu " "len=%llu returned %lld\n", fsp_str_dbg(fsp), (unsigned long long)in_file_id_volatile, (unsigned long long)in_offset, (unsigned long long)in_length, (long long)nread)); status = smb2_read_complete(req, nread, saved_errno); if (!NT_STATUS_IS_OK(status)) { tevent_req_nterror(req, status); } else { /* Success. */ tevent_req_done(req); } return tevent_req_post(req, ev); } static void smbd_smb2_read_pipe_done(struct tevent_req *subreq) { struct tevent_req *req = tevent_req_callback_data(subreq, struct tevent_req); struct smbd_smb2_read_state *state = tevent_req_data(req, struct smbd_smb2_read_state); NTSTATUS status; ssize_t nread = -1; bool is_data_outstanding; status = np_read_recv(subreq, &nread, &is_data_outstanding); TALLOC_FREE(subreq); if (!NT_STATUS_IS_OK(status)) { tevent_req_nterror(req, status); return; } if (nread == 0 && state->out_data.length != 0) { tevent_req_nterror(req, NT_STATUS_END_OF_FILE); return; } state->out_data.length = nread; state->out_remaining = 0; /* * TODO: add STATUS_BUFFER_OVERFLOW handling, once we also * handle it in SMB1 pipe_read_andx_done(). */ tevent_req_done(req); } static NTSTATUS smbd_smb2_read_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx, DATA_BLOB *out_data, uint32_t *out_remaining) { NTSTATUS status; struct smbd_smb2_read_state *state = tevent_req_data(req, struct smbd_smb2_read_state); if (tevent_req_is_nterror(req, &status)) { tevent_req_received(req); return status; } *out_data = state->out_data; talloc_steal(mem_ctx, out_data->data); *out_remaining = state->out_remaining; tevent_req_received(req); return NT_STATUS_OK; }