/* Unix SMB/CIFS implementation. client file read/write routines Copyright (C) Andrew Tridgell 1994-1998 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" /**************************************************************************** Calculate the recommended read buffer size ****************************************************************************/ static size_t cli_read_max_bufsize(struct cli_state *cli) { if (!client_is_signing_on(cli) && !cli_encryption_on(cli) && (cli->posix_capabilities & CIFS_UNIX_LARGE_READ_CAP)) { return CLI_SAMBA_MAX_POSIX_LARGE_READX_SIZE; } if (cli->capabilities & CAP_LARGE_READX) { return cli->is_samba ? CLI_SAMBA_MAX_LARGE_READX_SIZE : CLI_WINDOWS_MAX_LARGE_READX_SIZE; } return (cli->max_xmit - (smb_size+32)) & ~1023; } /* * Send a read&x request */ struct async_req *cli_read_andx_send(TALLOC_CTX *mem_ctx, struct cli_state *cli, int fnum, off_t offset, size_t size) { struct async_req *result; struct cli_request *req; bool bigoffset = False; char *enc_buf; if (size > cli_read_max_bufsize(cli)) { DEBUG(0, ("cli_read_andx_send got size=%d, can only handle " "size=%d\n", (int)size, (int)cli_read_max_bufsize(cli))); return NULL; } result = cli_request_new(mem_ctx, cli->event_ctx, cli, 12, 0, &req); if (result == NULL) { DEBUG(0, ("cli_request_new failed\n")); return NULL; } req = cli_request_get(result); req->data.read.ofs = offset; req->data.read.size = size; req->data.read.received = 0; req->data.read.rcvbuf = NULL; if ((SMB_BIG_UINT)offset >> 32) bigoffset = True; cli_set_message(req->outbuf, bigoffset ? 12 : 10, 0, False); SCVAL(req->outbuf,smb_com,SMBreadX); SSVAL(req->outbuf,smb_tid,cli->cnum); cli_setup_packet_buf(cli, req->outbuf); SCVAL(req->outbuf,smb_vwv0,0xFF); SCVAL(req->outbuf,smb_vwv0+1,0); SSVAL(req->outbuf,smb_vwv1,0); SSVAL(req->outbuf,smb_vwv2,fnum); SIVAL(req->outbuf,smb_vwv3,offset); SSVAL(req->outbuf,smb_vwv5,size); SSVAL(req->outbuf,smb_vwv6,size); SSVAL(req->outbuf,smb_vwv7,(size >> 16)); SSVAL(req->outbuf,smb_vwv8,0); SSVAL(req->outbuf,smb_vwv9,0); SSVAL(req->outbuf,smb_mid,req->mid); if (bigoffset) { SIVAL(req->outbuf, smb_vwv10, (((SMB_BIG_UINT)offset)>>32) & 0xffffffff); } cli_calculate_sign_mac(cli, req->outbuf); event_fd_set_writeable(cli->fd_event); if (cli_encryption_on(cli)) { NTSTATUS status; status = cli_encrypt_message(cli, req->outbuf, &enc_buf); if (!NT_STATUS_IS_OK(status)) { DEBUG(0, ("Error in encrypting client message. " "Error %s\n", nt_errstr(status))); TALLOC_FREE(req); return NULL; } req->outbuf = enc_buf; req->enc_state = cli->trans_enc_state; } return result; } /* * Pull the data out of a finished async read_and_x request. rcvbuf is * talloced from the request, so better make sure that you copy it away before * you talloc_free(req). "rcvbuf" is NOT a talloc_ctx of its own, so do not * talloc_move it! */ NTSTATUS cli_read_andx_recv(struct async_req *req, ssize_t *received, uint8_t **rcvbuf) { struct cli_request *cli_req = cli_request_get(req); NTSTATUS status; size_t size; SMB_ASSERT(req->state >= ASYNC_REQ_DONE); if (req->state == ASYNC_REQ_ERROR) { return req->status; } status = cli_pull_error(cli_req->inbuf); if (NT_STATUS_IS_ERR(status)) { return status; } /* size is the number of bytes the server returned. * Might be zero. */ size = SVAL(cli_req->inbuf, smb_vwv5); size |= (((unsigned int)(SVAL(cli_req->inbuf, smb_vwv7))) << 16); if (size > cli_req->data.read.size) { DEBUG(5,("server returned more than we wanted!\n")); return NT_STATUS_UNEXPECTED_IO_ERROR; } if (size < 0) { DEBUG(5,("read return < 0!\n")); return NT_STATUS_UNEXPECTED_IO_ERROR; } *rcvbuf = (uint8_t *) (smb_base(cli_req->inbuf) + SVAL(cli_req->inbuf, smb_vwv6)); *received = size; return NT_STATUS_OK; } /* * Parallel read support. * * cli_pull sends as many read&x requests as the server would allow via * max_mux at a time. When replies flow back in, the data is written into * the callback function "sink" in the right order. */ struct cli_pull_state { struct async_req *req; struct cli_state *cli; uint16_t fnum; off_t start_offset; SMB_OFF_T size; NTSTATUS (*sink)(char *buf, size_t n, void *priv); void *priv; size_t chunk_size; /* * Outstanding requests */ int num_reqs; struct async_req **reqs; /* * For how many bytes did we send requests already? */ off_t requested; /* * Next request index to push into "sink". This walks around the "req" * array, taking care that the requests are pushed to "sink" in the * right order. If necessary (i.e. replies don't come in in the right * order), replies are held back in "reqs". */ int top_req; /* * How many bytes did we push into "sink"? */ off_t pushed; }; static char *cli_pull_print(TALLOC_CTX *mem_ctx, struct async_req *req) { struct cli_pull_state *state = talloc_get_type_abort( req->private_data, struct cli_pull_state); char *result; result = async_req_print(mem_ctx, req); if (result == NULL) { return NULL; } return talloc_asprintf_append_buffer( result, "num_reqs=%d, top_req=%d", state->num_reqs, state->top_req); } static void cli_pull_read_done(struct async_req *read_req); /* * Prepare an async pull request */ struct async_req *cli_pull_send(TALLOC_CTX *mem_ctx, struct cli_state *cli, uint16_t fnum, off_t start_offset, SMB_OFF_T size, size_t window_size, NTSTATUS (*sink)(char *buf, size_t n, void *priv), void *priv) { struct async_req *result; struct cli_pull_state *state; int i; result = async_req_new(mem_ctx, cli->event_ctx); if (result == NULL) { goto failed; } state = talloc(result, struct cli_pull_state); if (state == NULL) { goto failed; } result->private_data = state; result->print = cli_pull_print; state->req = result; state->cli = cli; state->fnum = fnum; state->start_offset = start_offset; state->size = size; state->sink = sink; state->priv = priv; state->pushed = 0; state->top_req = 0; if (size == 0) { if (!async_post_status(result, NT_STATUS_OK)) { goto failed; } return result; } state->chunk_size = cli_read_max_bufsize(cli); state->num_reqs = MAX(window_size/state->chunk_size, 1); state->num_reqs = MIN(state->num_reqs, cli->max_mux); state->reqs = TALLOC_ZERO_ARRAY(state, struct async_req *, state->num_reqs); if (state->reqs == NULL) { goto failed; } state->requested = 0; for (i=0; i<state->num_reqs; i++) { SMB_OFF_T size_left; size_t request_thistime; if (state->requested >= size) { state->num_reqs = i; break; } size_left = size - state->requested; request_thistime = MIN(size_left, state->chunk_size); state->reqs[i] = cli_read_andx_send( state->reqs, cli, fnum, state->start_offset + state->requested, request_thistime); if (state->reqs[i] == NULL) { goto failed; } state->reqs[i]->async.fn = cli_pull_read_done; state->reqs[i]->async.priv = result; state->requested += request_thistime; } return result; failed: TALLOC_FREE(result); return NULL; } /* * Handle incoming read replies, push the data into sink and send out new * requests if necessary. */ static void cli_pull_read_done(struct async_req *read_req) { struct async_req *pull_req = talloc_get_type_abort( read_req->async.priv, struct async_req); struct cli_pull_state *state = talloc_get_type_abort( pull_req->private_data, struct cli_pull_state); struct cli_request *read_state = cli_request_get(read_req); NTSTATUS status; status = cli_read_andx_recv(read_req, &read_state->data.read.received, &read_state->data.read.rcvbuf); if (!NT_STATUS_IS_OK(status)) { async_req_error(state->req, status); return; } /* * This loop is the one to take care of out-of-order replies. All * pending requests are in state->reqs, state->reqs[top_req] is the * one that is to be pushed next. If however a request later than * top_req is replied to, then we can't push yet. If top_req is * replied to at a later point then, we need to push all the finished * requests. */ while (state->reqs[state->top_req] != NULL) { struct cli_request *top_read; DEBUG(11, ("cli_pull_read_done: top_req = %d\n", state->top_req)); if (state->reqs[state->top_req]->state < ASYNC_REQ_DONE) { DEBUG(11, ("cli_pull_read_done: top request not yet " "done\n")); return; } top_read = cli_request_get(state->reqs[state->top_req]); DEBUG(10, ("cli_pull_read_done: Pushing %d bytes, %d already " "pushed\n", (int)top_read->data.read.received, (int)state->pushed)); status = state->sink((char *)top_read->data.read.rcvbuf, top_read->data.read.received, state->priv); if (!NT_STATUS_IS_OK(status)) { async_req_error(state->req, status); return; } state->pushed += top_read->data.read.received; TALLOC_FREE(state->reqs[state->top_req]); if (state->requested < state->size) { struct async_req *new_req; SMB_OFF_T size_left; size_t request_thistime; size_left = state->size - state->requested; request_thistime = MIN(size_left, state->chunk_size); DEBUG(10, ("cli_pull_read_done: Requesting %d bytes " "at %d, position %d\n", (int)request_thistime, (int)(state->start_offset + state->requested), state->top_req)); new_req = cli_read_andx_send( state->reqs, state->cli, state->fnum, state->start_offset + state->requested, request_thistime); if (async_req_nomem(new_req, state->req)) { return; } new_req->async.fn = cli_pull_read_done; new_req->async.priv = pull_req; state->reqs[state->top_req] = new_req; state->requested += request_thistime; } state->top_req = (state->top_req+1) % state->num_reqs; } async_req_done(pull_req); } NTSTATUS cli_pull_recv(struct async_req *req, ssize_t *received) { struct cli_pull_state *state = talloc_get_type_abort( req->private_data, struct cli_pull_state); SMB_ASSERT(req->state >= ASYNC_REQ_DONE); if (req->state == ASYNC_REQ_ERROR) { return req->status; } *received = state->pushed; return NT_STATUS_OK; } NTSTATUS cli_pull(struct cli_state *cli, uint16_t fnum, off_t start_offset, SMB_OFF_T size, size_t window_size, NTSTATUS (*sink)(char *buf, size_t n, void *priv), void *priv, ssize_t *received) { TALLOC_CTX *frame = talloc_stackframe(); struct async_req *req; NTSTATUS result = NT_STATUS_NO_MEMORY; if (cli_tmp_event_ctx(frame, cli) == NULL) { goto nomem; } req = cli_pull_send(frame, cli, fnum, start_offset, size, window_size, sink, priv); if (req == NULL) { goto nomem; } while (req->state < ASYNC_REQ_DONE) { event_loop_once(cli->event_ctx); } result = cli_pull_recv(req, received); nomem: TALLOC_FREE(frame); return result; } static NTSTATUS cli_read_sink(char *buf, size_t n, void *priv) { char **pbuf = (char **)priv; memcpy(*pbuf, buf, n); *pbuf += n; return NT_STATUS_OK; } ssize_t cli_read(struct cli_state *cli, int fnum, char *buf, off_t offset, size_t size) { NTSTATUS status; ssize_t ret; status = cli_pull(cli, fnum, offset, size, size, cli_read_sink, &buf, &ret); if (!NT_STATUS_IS_OK(status)) { cli_set_error(cli, status); return -1; } return ret; } #if 0 /* relies on client_receive_smb(), now a static in libsmb/clientgen.c */ /* This call is INCOMPATIBLE with SMB signing. If you remove the #if 0 you must fix ensure you don't attempt to sign the packets - data *will* be currupted */ /**************************************************************************** Issue a single SMBreadraw and don't wait for a reply. ****************************************************************************/ static bool cli_issue_readraw(struct cli_state *cli, int fnum, off_t offset, size_t size, int i) { if (!cli->sign_info.use_smb_signing) { DEBUG(0, ("Cannot use readraw and SMB Signing\n")); return False; } memset(cli->outbuf,'\0',smb_size); memset(cli->inbuf,'\0',smb_size); cli_set_message(cli->outbuf,10,0,True); SCVAL(cli->outbuf,smb_com,SMBreadbraw); SSVAL(cli->outbuf,smb_tid,cli->cnum); cli_setup_packet(cli); SSVAL(cli->outbuf,smb_vwv0,fnum); SIVAL(cli->outbuf,smb_vwv1,offset); SSVAL(cli->outbuf,smb_vwv2,size); SSVAL(cli->outbuf,smb_vwv3,size); SSVAL(cli->outbuf,smb_mid,cli->mid + i); return cli_send_smb(cli); } /**************************************************************************** Tester for the readraw call. ****************************************************************************/ ssize_t cli_readraw(struct cli_state *cli, int fnum, char *buf, off_t offset, size_t size) { char *p; int size2; size_t readsize; ssize_t total = 0; if (size == 0) return 0; /* * Set readsize to the maximum size we can handle in one readraw. */ readsize = 0xFFFF; while (total < size) { readsize = MIN(readsize, size-total); /* Issue a read and receive a reply */ if (!cli_issue_readraw(cli, fnum, offset, readsize, 0)) return -1; if (!client_receive_smb(cli->fd, cli->inbuf, cli->timeout)) return -1; size2 = smb_len(cli->inbuf); if (size2 > readsize) { DEBUG(5,("server returned more than we wanted!\n")); return -1; } else if (size2 < 0) { DEBUG(5,("read return < 0!\n")); return -1; } /* Copy data into buffer */ if (size2) { p = cli->inbuf + 4; memcpy(buf + total, p, size2); } total += size2; offset += size2; /* * If the server returned less than we asked for we're at EOF. */ if (size2 < readsize) break; } return total; } #endif /**************************************************************************** Issue a single SMBwrite and don't wait for a reply. ****************************************************************************/ static bool cli_issue_write(struct cli_state *cli, int fnum, off_t offset, uint16 mode, const char *buf, size_t size, int i) { char *p; bool large_writex = false; /* We can only do direct writes if not signing and not encrypting. */ bool direct_writes = !client_is_signing_on(cli) && !cli_encryption_on(cli); if (!direct_writes && size + 1 > cli->bufsize) { cli->outbuf = (char *)SMB_REALLOC(cli->outbuf, size + 1024); if (!cli->outbuf) { return False; } cli->inbuf = (char *)SMB_REALLOC(cli->inbuf, size + 1024); if (cli->inbuf == NULL) { SAFE_FREE(cli->outbuf); return False; } cli->bufsize = size + 1024; } memset(cli->outbuf,'\0',smb_size); memset(cli->inbuf,'\0',smb_size); if (cli->capabilities & CAP_LARGE_FILES) { large_writex = True; } if (large_writex) { cli_set_message(cli->outbuf,14,0,True); } else { cli_set_message(cli->outbuf,12,0,True); } SCVAL(cli->outbuf,smb_com,SMBwriteX); SSVAL(cli->outbuf,smb_tid,cli->cnum); cli_setup_packet(cli); SCVAL(cli->outbuf,smb_vwv0,0xFF); SSVAL(cli->outbuf,smb_vwv2,fnum); SIVAL(cli->outbuf,smb_vwv3,offset); SIVAL(cli->outbuf,smb_vwv5,0); SSVAL(cli->outbuf,smb_vwv7,mode); SSVAL(cli->outbuf,smb_vwv8,(mode & 0x0008) ? size : 0); /* * According to CIFS-TR-1p00, this following field should only * be set if CAP_LARGE_WRITEX is set. We should check this * locally. However, this check might already have been * done by our callers. */ SSVAL(cli->outbuf,smb_vwv9,(size>>16)); SSVAL(cli->outbuf,smb_vwv10,size); /* +1 is pad byte. */ SSVAL(cli->outbuf,smb_vwv11, smb_buf(cli->outbuf) - smb_base(cli->outbuf) + 1); if (large_writex) { SIVAL(cli->outbuf,smb_vwv12,(((SMB_BIG_UINT)offset)>>32) & 0xffffffff); } p = smb_base(cli->outbuf) + SVAL(cli->outbuf,smb_vwv11) -1; *p++ = '\0'; /* pad byte. */ if (!direct_writes) { memcpy(p, buf, size); } if (size > 0x1FFFF) { /* This is a POSIX 14 word large write. */ set_message_bcc(cli->outbuf, 0); /* Set bcc to zero. */ _smb_setlen_large(cli->outbuf,smb_size + 28 + 1 /* pad */ + size - 4); } else { cli_setup_bcc(cli, p+size); } SSVAL(cli->outbuf,smb_mid,cli->mid + i); show_msg(cli->outbuf); if (direct_writes) { /* For direct writes we now need to write the data * directly out of buf. */ return cli_send_smb_direct_writeX(cli, buf, size); } else { return cli_send_smb(cli); } } /**************************************************************************** write to a file write_mode: 0x0001 disallow write cacheing 0x0002 return bytes remaining 0x0004 use raw named pipe protocol 0x0008 start of message mode named pipe protocol ****************************************************************************/ ssize_t cli_write(struct cli_state *cli, int fnum, uint16 write_mode, const char *buf, off_t offset, size_t size) { ssize_t bwritten = 0; unsigned int issued = 0; unsigned int received = 0; int mpx = 1; size_t writesize; int blocks; if(cli->max_mux > 1) { mpx = cli->max_mux-1; } else { mpx = 1; } /* Default (small) writesize. */ writesize = (cli->max_xmit - (smb_size+32)) & ~1023; if (write_mode == 0 && !client_is_signing_on(cli) && !cli_encryption_on(cli) && (cli->posix_capabilities & CIFS_UNIX_LARGE_WRITE_CAP) && (cli->capabilities & CAP_LARGE_FILES)) { /* Only do massive writes if we can do them direct * with no signing or encrypting - not on a pipe. */ writesize = CLI_SAMBA_MAX_POSIX_LARGE_WRITEX_SIZE; } else if (cli->capabilities & CAP_LARGE_WRITEX) { if (cli->is_samba) { writesize = CLI_SAMBA_MAX_LARGE_WRITEX_SIZE; } else if (!client_is_signing_on(cli)) { /* Windows restricts signed writes to max_xmit. * Found by Volker. */ writesize = CLI_WINDOWS_MAX_LARGE_WRITEX_SIZE; } } blocks = (size + (writesize-1)) / writesize; while (received < blocks) { while ((issued - received < mpx) && (issued < blocks)) { ssize_t bsent = issued * writesize; ssize_t size1 = MIN(writesize, size - bsent); if (!cli_issue_write(cli, fnum, offset + bsent, write_mode, buf + bsent, size1, issued)) return -1; issued++; } if (!cli_receive_smb(cli)) { return bwritten; } received++; if (cli_is_error(cli)) break; bwritten += SVAL(cli->inbuf, smb_vwv2); bwritten += (((int)(SVAL(cli->inbuf, smb_vwv4)))<<16); } while (received < issued && cli_receive_smb(cli)) { received++; } return bwritten; } /**************************************************************************** write to a file using a SMBwrite and not bypassing 0 byte writes ****************************************************************************/ ssize_t cli_smbwrite(struct cli_state *cli, int fnum, char *buf, off_t offset, size_t size1) { char *p; ssize_t total = 0; do { size_t size = MIN(size1, cli->max_xmit - 48); memset(cli->outbuf,'\0',smb_size); memset(cli->inbuf,'\0',smb_size); cli_set_message(cli->outbuf,5, 0,True); SCVAL(cli->outbuf,smb_com,SMBwrite); SSVAL(cli->outbuf,smb_tid,cli->cnum); cli_setup_packet(cli); SSVAL(cli->outbuf,smb_vwv0,fnum); SSVAL(cli->outbuf,smb_vwv1,size); SIVAL(cli->outbuf,smb_vwv2,offset); SSVAL(cli->outbuf,smb_vwv4,0); p = smb_buf(cli->outbuf); *p++ = 1; SSVAL(p, 0, size); p += 2; memcpy(p, buf + total, size); p += size; cli_setup_bcc(cli, p); if (!cli_send_smb(cli)) return -1; if (!cli_receive_smb(cli)) return -1; if (cli_is_error(cli)) return -1; size = SVAL(cli->inbuf,smb_vwv0); if (size == 0) break; size1 -= size; total += size; offset += size; } while (size1); return total; }