libcli/smb: add smb1cli_readx*

Pair-Programmed-With: Stefan Metzmacher <metze@samba.org>

Signed-off-by: Gregor Beck <gbeck@sernet.de>
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Andreas Schneider <asn@samba.org>

3 files changed, 238 insertions, 0 deletions

diff --git a/libcli/smb/smb1cli_read.c b/libcli/smb/smb1cli_read.c
new file mode 100644
index 00000000000..ab250abf143
--- /dev/null
+++ b/libcli/smb/smb1cli_read.c
@@ -0,0 +1,224 @@
+/*
+   Unix SMB/CIFS implementation.
+
+   Copyright (C) Gregor Beck 2013
+
+   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 smb1cli_readx_state {
+	uint32_t size;
+	uint16_t vwv[12];
+	NTSTATUS status;
+	uint32_t received;
+	uint8_t *buf;
+};
+
+static void smb1cli_readx_done(struct tevent_req *subreq);
+
+/**
+ * Send an asynchrounus SMB_COM_READ_ANDX request.
+ * <a href="http://msdn.microsoft.com/en-us/library/ee441839.aspx">MS-CIFS 2.2.4.42.1</a>,
+ * <a href="http://msdn.microsoft.com/en-us/library/ff470250.aspx">MS-SMB 2.2.4.2.1</a>
+ * @see smb1cli_readx_recv()
+ * @todo fix API (min/max size, timeout)
+ *
+ * @param[in] mem_ctx The memory context for the result.
+ * @param[in] ev The event context to work on.
+ * @param[in] conn The smb connection.
+ * @param[in] timeout_msec If positiv a timeout for the request.
+ * @param[in] pid The process identifier
+ * @param[in] tcon The smb tree connect.
+ * @param[in] session The smb session.
+ * @param[in] fnum The file id of the file the data should be read from.
+ * @param[in] offset The offset in bytes from the begin of file where to start reading.
+ * @param[in] size The number of bytes to read.
+ *
+ * @return a tevent_req or NULL
+ */
+struct tevent_req *smb1cli_readx_send(TALLOC_CTX *mem_ctx,
+				      struct tevent_context *ev,
+				      struct smbXcli_conn *conn,
+				      uint32_t timeout_msec,
+				      uint32_t pid,
+				      struct smbXcli_tcon *tcon,
+				      struct smbXcli_session *session,
+				      uint16_t fnum,
+				      uint64_t offset,
+				      uint32_t size)
+{
+	NTSTATUS status;
+	struct tevent_req *req, *subreq;
+	struct smb1cli_readx_state *state;
+	uint8_t wct = 10;
+
+	req = tevent_req_create(mem_ctx, &state, struct smb1cli_readx_state);
+	if (req == NULL) {
+		return NULL;
+	}
+	state->size = size;
+
+	SCVAL(state->vwv + 0, 0, 0xFF);
+	SCVAL(state->vwv + 0, 1, 0);
+	SSVAL(state->vwv + 1, 0, 0);
+	SSVAL(state->vwv + 2, 0, fnum);
+	SIVAL(state->vwv + 3, 0, offset);
+	SSVAL(state->vwv + 5, 0, size);
+	SSVAL(state->vwv + 6, 0, size);
+	SSVAL(state->vwv + 7, 0, (size >> 16));
+	SSVAL(state->vwv + 8, 0, 0);
+	SSVAL(state->vwv + 9, 0, 0);
+
+	if (smb1cli_conn_capabilities(conn) & CAP_LARGE_FILES) {
+		SIVAL(state->vwv + 10, 0,
+		      (((uint64_t)offset)>>32) & 0xffffffff);
+		wct = 12;
+	} else {
+		if ((((uint64_t)offset) & 0xffffffff00000000LL) != 0) {
+			DEBUG(10, ("smb1cli_readx_send got large offset where "
+				   "the server does not support it\n"));
+			tevent_req_nterror(req, NT_STATUS_INVALID_PARAMETER_MIX);
+			return tevent_req_post(req, ev);
+		}
+	}
+
+	subreq = smb1cli_req_create(state, ev, conn, SMBreadX,
+				    0, 0, /* *_flags */
+				    0, 0, /* *_flags2 */
+				    timeout_msec, pid, tcon, session,
+				    wct, state->vwv,
+				    0, NULL);
+	if (tevent_req_nomem(subreq, req)) {
+		return tevent_req_post(req, ev);
+	}
+	tevent_req_set_callback(subreq, smb1cli_readx_done, req);
+
+	status = smb1cli_req_chain_submit(&subreq, 1);
+	if (tevent_req_nterror(req, status)) {
+		return tevent_req_post(req, ev);
+	}
+
+	return req;
+}
+
+static void smb1cli_readx_done(struct tevent_req *subreq)
+{
+	struct tevent_req *req = tevent_req_callback_data(
+		subreq, struct tevent_req);
+	struct smb1cli_readx_state *state = tevent_req_data(
+		req, struct smb1cli_readx_state);
+	struct iovec *recv_iov = NULL;
+	uint8_t wct;
+	uint16_t *vwv;
+	uint32_t num_bytes;
+	uint8_t *bytes;
+	uint16_t data_offset;
+	uint32_t bytes_offset;
+	static const struct smb1cli_req_expected_response expected[] = {
+	{
+		.status = NT_STATUS_OK,
+		.wct = 0x0C
+	},
+	};
+
+	state->status = smb1cli_req_recv(subreq, state,
+					 &recv_iov,
+					 NULL, /* phdr */
+					 &wct,
+					 &vwv,
+					 NULL, /* pvwv_offset */
+					 &num_bytes,
+					 &bytes,
+					 &bytes_offset,
+					 NULL, /* inbuf */
+					 expected, ARRAY_SIZE(expected));
+	TALLOC_FREE(subreq);
+	if (tevent_req_nterror(req, state->status)) {
+		return;
+	}
+
+	/* size is the number of bytes the server returned.
+	 * Might be zero. */
+	state->received = SVAL(vwv + 5, 0);
+	state->received |= (((unsigned int)SVAL(vwv + 7, 0)) << 16);
+
+	if (state->received > state->size) {
+		DEBUG(5,("server returned more than we wanted!\n"));
+		tevent_req_nterror(req, NT_STATUS_UNEXPECTED_IO_ERROR);
+		return;
+	}
+
+	/*
+	 * bcc field must be valid for small reads, for large reads the 16-bit
+	 * bcc field can't be correct.
+	 */
+	if ((state->received < 0xffff) && (state->received > num_bytes)) {
+		DEBUG(5, ("server announced more bytes than sent\n"));
+		tevent_req_nterror(req, NT_STATUS_INVALID_NETWORK_RESPONSE);
+		return;
+	}
+
+	data_offset = SVAL(vwv+6, 0);
+	if (data_offset < bytes_offset) {
+		DEBUG(5, ("server returned invalid read&x data offset\n"));
+		tevent_req_nterror(req, NT_STATUS_INVALID_NETWORK_RESPONSE);
+		return;
+	}
+	if (smb_buffer_oob(num_bytes, data_offset - bytes_offset, state->received)) {
+		DEBUG(5, ("server returned invalid read&x data offset\n"));
+		tevent_req_nterror(req, NT_STATUS_INVALID_NETWORK_RESPONSE);
+		return;
+	}
+
+	state->buf = bytes + (data_offset - bytes_offset);
+
+	tevent_req_done(req);
+}
+
+/**
+ * Receive the response to an asynchronous SMB_COM_READ_ANDX request.
+ * <a href="http://msdn.microsoft.com/en-us/library/ee441872.aspx">MS-CIFS 2.2.4.42.2</a>,
+ * <a href="http://msdn.microsoft.com/en-us/library/ff470017.aspx">MS-SMB 2.2.4.2.2</a>
+ *
+ * @warning 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!
+ *
+ * @param[in] req A tevent request created with smb1cli_readx_send()
+ * @param[out] received The number of bytes received.
+ * @param[out] rcvbuf Pointer to the bytes received.
+ *
+ * @return NT_STATUS_OK on succsess.
+ */
+NTSTATUS smb1cli_readx_recv(struct tevent_req *req,
+			    uint32_t *received,
+			    uint8_t **rcvbuf)
+{
+	struct smb1cli_readx_state *state = tevent_req_data(
+		req, struct smb1cli_readx_state);
+	NTSTATUS status;
+
+	if (tevent_req_is_nterror(req, &status)) {
+		return status;
+	}
+	*received = state->received;
+	*rcvbuf = state->buf;
+	return NT_STATUS_OK;
+}
diff --git a/libcli/smb/smbXcli_base.h b/libcli/smb/smbXcli_base.h
index 395c00d3a28..888242b1126 100644
--- a/libcli/smb/smbXcli_base.h
+++ b/libcli/smb/smbXcli_base.h
@@ -281,6 +281,19 @@ NTSTATUS smb1cli_writex(struct smbXcli_conn *conn,
 			uint32_t size,
 			uint32_t *pwritten,
 			uint16_t *pavailable);
+struct tevent_req *smb1cli_readx_send(TALLOC_CTX *mem_ctx,
+				      struct tevent_context *ev,
+				      struct smbXcli_conn *conn,
+				      uint32_t timeout_msec,
+				      uint32_t pid,
+				      struct smbXcli_tcon *tcon,
+				      struct smbXcli_session *session,
+				      uint16_t fnum,
+				      uint64_t offset,
+				      uint32_t size);
+NTSTATUS smb1cli_readx_recv(struct tevent_req *req,
+			    uint32_t *received,
+			    uint8_t **rcvbuf);
 
 bool smb2cli_conn_req_possible(struct smbXcli_conn *conn, uint32_t *max_dyn_len);
 uint32_t smb2cli_conn_server_capabilities(struct smbXcli_conn *conn);
diff --git a/libcli/smb/wscript b/libcli/smb/wscript
index 6dfbe9efabb..52390100474 100755
--- a/libcli/smb/wscript
+++ b/libcli/smb/wscript
@@ -26,6 +26,7 @@ def build(bld):
                 smb1cli_create.c
                 smb1cli_close.c
                 smb1cli_write.c
+                smb1cli_read.c
 		smb2cli_session.c
                 smb2cli_create.c
                 smb2cli_close.c