diff options
Diffstat (limited to '')
-rw-r--r-- | libcli/smb/smb2cli_read.c | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/libcli/smb/smb2cli_read.c b/libcli/smb/smb2cli_read.c new file mode 100644 index 0000000..c7f4874 --- /dev/null +++ b/libcli/smb/smb2cli_read.c @@ -0,0 +1,218 @@ +/* + Unix SMB/CIFS implementation. + smb2 lib + Copyright (C) Volker Lendecke 2011 + + 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/network.h" +#include "lib/util/tevent_ntstatus.h" +#include "smb_common.h" +#include "smbXcli_base.h" + +struct smb2cli_read_state { + uint8_t fixed[48]; + uint8_t dyn_pad[1]; + struct iovec *recv_iov; + uint8_t *data; + uint32_t data_length; + bool out_valid; +}; + +static void smb2cli_read_done(struct tevent_req *subreq); + +struct tevent_req *smb2cli_read_send(TALLOC_CTX *mem_ctx, + struct tevent_context *ev, + struct smbXcli_conn *conn, + uint32_t timeout_msec, + struct smbXcli_session *session, + struct smbXcli_tcon *tcon, + uint32_t length, + uint64_t offset, + uint64_t fid_persistent, + uint64_t fid_volatile, + uint64_t minimum_count, + uint64_t remaining_bytes) +{ + struct tevent_req *req, *subreq; + struct smb2cli_read_state *state; + uint8_t *fixed; + + req = tevent_req_create(mem_ctx, &state, + struct smb2cli_read_state); + if (req == NULL) { + return NULL; + } + + fixed = state->fixed; + + SSVAL(fixed, 0, 49); + SIVAL(fixed, 4, length); + SBVAL(fixed, 8, offset); + SBVAL(fixed, 16, fid_persistent); + SBVAL(fixed, 24, fid_volatile); + SBVAL(fixed, 32, minimum_count); + SBVAL(fixed, 40, remaining_bytes); + + subreq = smb2cli_req_send(state, ev, conn, SMB2_OP_READ, + 0, 0, /* flags */ + timeout_msec, + tcon, + session, + state->fixed, sizeof(state->fixed), + state->dyn_pad, sizeof(state->dyn_pad), + length); /* max_dyn_len */ + if (tevent_req_nomem(subreq, req)) { + return tevent_req_post(req, ev); + } + tevent_req_set_callback(subreq, smb2cli_read_done, req); + return req; +} + +static void smb2cli_read_done(struct tevent_req *subreq) +{ + struct tevent_req *req = tevent_req_callback_data( + subreq, struct tevent_req); + struct smb2cli_read_state *state = + tevent_req_data(req, + struct smb2cli_read_state); + NTSTATUS status; + NTSTATUS error; + struct iovec *iov; + const uint8_t dyn_ofs = SMB2_HDR_BODY + 0x10; + DATA_BLOB dyn_buffer = data_blob_null; + uint8_t data_offset; + DATA_BLOB data_buffer = data_blob_null; + uint32_t next_offset = 0; /* this variable is completely ignored */ + static const struct smb2cli_req_expected_response expected[] = { + { + .status = STATUS_BUFFER_OVERFLOW, + .body_size = 0x11 + }, + { + .status = NT_STATUS_OK, + .body_size = 0x11 + } + }; + + status = smb2cli_req_recv(subreq, state, &iov, + expected, ARRAY_SIZE(expected)); + TALLOC_FREE(subreq); + if (NT_STATUS_EQUAL(status, STATUS_BUFFER_OVERFLOW)) { + /* no error */ + } else { + if (tevent_req_nterror(req, status)) { + return; + } + } + + data_offset = CVAL(iov[1].iov_base, 2); + state->data_length = IVAL(iov[1].iov_base, 4); + + dyn_buffer = data_blob_const((uint8_t *)iov[2].iov_base, + iov[2].iov_len); + + error = smb2cli_parse_dyn_buffer(dyn_ofs, + dyn_buffer, + dyn_ofs, /* min_offset */ + data_offset, + state->data_length, + dyn_buffer.length, /* max_length */ + &next_offset, + &data_buffer); + if (tevent_req_nterror(req, error)) { + return; + } + + state->recv_iov = iov; + state->data = data_buffer.data; + + state->out_valid = true; + + if (tevent_req_nterror(req, status)) { + return; + } + + tevent_req_done(req); +} + +NTSTATUS smb2cli_read_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx, + uint8_t **data, uint32_t *data_length) +{ + struct smb2cli_read_state *state = + tevent_req_data(req, + struct smb2cli_read_state); + NTSTATUS status = NT_STATUS_OK; + + if (tevent_req_is_nterror(req, &status) && !state->out_valid) { + *data_length = 0; + *data = NULL; + tevent_req_received(req); + return status; + } + talloc_steal(mem_ctx, state->recv_iov); + *data_length = state->data_length; + *data = state->data; + tevent_req_received(req); + return status; +} + +NTSTATUS smb2cli_read(struct smbXcli_conn *conn, + uint32_t timeout_msec, + struct smbXcli_session *session, + struct smbXcli_tcon *tcon, + uint32_t length, + uint64_t offset, + uint64_t fid_persistent, + uint64_t fid_volatile, + uint64_t minimum_count, + uint64_t remaining_bytes, + TALLOC_CTX *mem_ctx, + uint8_t **data, + uint32_t *data_length) +{ + TALLOC_CTX *frame = talloc_stackframe(); + struct tevent_context *ev; + struct tevent_req *req; + NTSTATUS status = NT_STATUS_NO_MEMORY; + + if (smbXcli_conn_has_async_calls(conn)) { + /* + * Can't use sync call while an async call is in flight + */ + status = NT_STATUS_INVALID_PARAMETER; + goto fail; + } + ev = samba_tevent_context_init(frame); + if (ev == NULL) { + goto fail; + } + req = smb2cli_read_send(frame, ev, + conn, timeout_msec, session, tcon, + length, offset, + fid_persistent, fid_volatile, + minimum_count, remaining_bytes); + if (req == NULL) { + goto fail; + } + if (!tevent_req_poll_ntstatus(req, ev, &status)) { + goto fail; + } + status = smb2cli_read_recv(req, mem_ctx, data, data_length); + fail: + TALLOC_FREE(frame); + return status; +} |