s3:smbd: add infrastructure for SMB2 support

This is disabled by default and activated by
"max protocol = SMB2".

metze

4 files changed, 1050 insertions, 0 deletions

diff --git a/source3/Makefile.in b/source3/Makefile.in
index 31ef29ad15..17558c97f9 100644
--- a/source3/Makefile.in
+++ b/source3/Makefile.in
@@ -748,6 +748,7 @@ SMBD_OBJ_SRV = smbd/files.o smbd/chgpasswd.o smbd/connection.o \
 	       smbd/dmapi.o smbd/signing.o \
 	       smbd/file_access.o \
 	       smbd/dnsregister.o smbd/globals.o \
+	       smbd/smb2_server.o \
 	       $(MANGLE_OBJ) @VFS_STATIC@
 
 SMBD_OBJ_BASE = $(PARAM_WITHOUT_REG_OBJ) $(SMBD_OBJ_SRV) $(LIBSMB_OBJ) \
diff --git a/source3/smbd/globals.h b/source3/smbd/globals.h
index b646bc30fd..e69243f4b4 100644
--- a/source3/smbd/globals.h
+++ b/source3/smbd/globals.h
@@ -199,11 +199,87 @@ struct child_pid;
 extern struct child_pid *children;
 extern int num_children;
 
+struct tstream_context;
+struct smbd_smb2_request;
+
+bool smbd_is_smb2_header(const uint8_t *inbuf, size_t size);
+
+void smbd_smb2_first_negprot(struct smbd_server_connection *conn,
+			     const uint8_t *inbuf, size_t size);
+
+NTSTATUS smbd_smb2_request_error_ex(struct smbd_smb2_request *req,
+				    NTSTATUS status, DATA_BLOB *info);
+NTSTATUS smbd_smb2_request_error(struct smbd_smb2_request *req,
+				 NTSTATUS status);
+NTSTATUS smbd_smb2_request_done(struct smbd_smb2_request *req,
+				DATA_BLOB body, DATA_BLOB *dyn);
+
+struct smbd_smb2_request {
+	TALLOC_CTX *mem_pool;
+
+	struct smbd_server_connection *conn;
+
+	int current_idx;
+
+	struct {
+		/* the NBT header is not allocated */
+		uint8_t nbt_hdr[4];
+		/*
+		 * vector[0] NBT
+		 * .
+		 * vector[1] SMB2
+		 * vector[2] fixed body
+		 * vector[3] dynamic body
+		 * .
+		 * .
+		 * .
+		 * vector[4] SMB2
+		 * vector[5] fixed body
+		 * vector[6] dynamic body
+		 * .
+		 * .
+		 * .
+		 */
+		struct iovec *vector;
+		int vector_count;
+	} in;
+	struct {
+		/* the NBT header is not allocated */
+		uint8_t nbt_hdr[4];
+		/*
+		 * vector[0] NBT
+		 * .
+		 * vector[1] SMB2
+		 * vector[2] fixed body
+		 * vector[3] dynamic body
+		 * .
+		 * .
+		 * .
+		 * vector[4] SMB2
+		 * vector[5] fixed body
+		 * vector[6] dynamic body
+		 * .
+		 * .
+		 * .
+		 */
+		struct iovec *vector;
+		int vector_count;
+	} out;
+};
+
 struct smbd_server_connection {
 	struct fd_event *fde;
 	uint64_t num_requests;
 	struct smb_signing_state *signing_state;
+	bool allow_smb2;
+	struct {
+		struct tevent_context *event_ctx;
+		struct tevent_queue *recv_queue;
+		struct tevent_queue *send_queue;
+		struct tstream_context *stream;
+	} smb2;
 };
+
 extern struct smbd_server_connection *smbd_server_conn;
 
 void smbd_init_globals(void);
diff --git a/source3/smbd/process.c b/source3/smbd/process.c
index 0647b99ba0..5cad8bfc9a 100644
--- a/source3/smbd/process.c
+++ b/source3/smbd/process.c
@@ -1448,6 +1448,14 @@ static void process_smb(struct smbd_server_connection *conn,
 		goto done;
 	}
 
+	if (smbd_server_conn->allow_smb2) {
+		if (smbd_is_smb2_header(inbuf, nread)) {
+			smbd_smb2_first_negprot(smbd_server_conn, inbuf, nread);
+			return;
+		}
+		smbd_server_conn->allow_smb2 = false;
+	}
+
 	show_msg((char *)inbuf);
 
 	construct_reply((char *)inbuf,nread,unread_bytes,seqnum,encrypted,deferred_pcd);
@@ -2009,6 +2017,10 @@ void smbd_process(void)
 		exit_server("failed to create smbd_server_connection");
 	}
 
+	if (lp_maxprotocol() == PROTOCOL_SMB2) {
+		smbd_server_conn->allow_smb2 = true;
+	}
+
 	/* Ensure child is set to blocking mode */
 	set_blocking(smbd_server_fd(),True);
 
diff --git a/source3/smbd/smb2_server.c b/source3/smbd/smb2_server.c
new file mode 100644
index 0000000000..c63c8da43c
--- /dev/null
+++ b/source3/smbd/smb2_server.c
@@ -0,0 +1,961 @@
+/*
+   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 "smbd/globals.h"
+#include "../source4/libcli/smb2/smb2_constants.h"
+#include "../lib/tsocket/tsocket.h"
+
+bool smbd_is_smb2_header(const uint8_t *inbuf, size_t size)
+{
+	if (size < (4 + SMB2_HDR_BODY)) {
+		return false;
+	}
+
+	if (IVAL(inbuf, 4) != SMB2_MAGIC) {
+		return false;
+	}
+
+	return true;
+}
+
+static NTSTATUS smbd_initialize_smb2(struct smbd_server_connection *conn)
+{
+	NTSTATUS status;
+	int ret;
+
+	TALLOC_FREE(conn->fde);
+
+	conn->smb2.event_ctx = smbd_event_context();
+
+	conn->smb2.recv_queue = tevent_queue_create(conn, "smb2 recv queue");
+	if (conn->smb2.recv_queue == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	conn->smb2.send_queue = tevent_queue_create(conn, "smb2 send queue");
+	if (conn->smb2.send_queue == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	ret = tstream_bsd_existing_socket(conn, smbd_server_fd(),
+					  &conn->smb2.stream);
+	if (ret == -1) {
+		status = map_nt_error_from_unix(errno);
+		return status;
+	}
+
+	/* Ensure child is set to non-blocking mode */
+	set_blocking(smbd_server_fd(),false);
+	return NT_STATUS_OK;
+}
+
+#define smb2_len(buf) (PVAL(buf,3)|(PVAL(buf,2)<<8)|(PVAL(buf,1)<<16))
+#define _smb2_setlen(_buf,len) do { \
+	uint8_t *buf = (uint8_t *)_buf; \
+	buf[0] = 0; \
+	buf[1] = ((len)&0xFF0000)>>16; \
+	buf[2] = ((len)&0xFF00)>>8; \
+	buf[3] = (len)&0xFF; \
+} while (0)
+
+static void smb2_setup_nbt_length(struct iovec *vector, int count)
+{
+	size_t len = 0;
+	int i;
+
+	for (i=1; i < count; i++) {
+		len += vector[i].iov_len;
+	}
+
+	_smb2_setlen(vector[0].iov_base, len);
+}
+
+static NTSTATUS smbd_smb2_request_create(struct smbd_server_connection *conn,
+					 const uint8_t *inbuf, size_t size,
+					 struct smbd_smb2_request **_req)
+{
+	TALLOC_CTX *mem_pool;
+	struct smbd_smb2_request *req;
+	uint32_t protocol_version;
+	const uint8_t *inhdr = NULL;
+	off_t ofs = 0;
+	uint16_t cmd;
+	uint32_t next_command_ofs;
+
+	if (size < (4 + SMB2_HDR_BODY + 2)) {
+		DEBUG(0,("Invalid SMB2 packet length count %ld\n", (long)size));
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	inhdr = inbuf + 4;
+
+	protocol_version = IVAL(inhdr, SMB2_HDR_PROTOCOL_ID);
+	if (protocol_version != SMB2_MAGIC) {
+		DEBUG(0,("Invalid SMB packet: protocol prefix: 0x%08X\n",
+			 protocol_version));
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	cmd = SVAL(inhdr, SMB2_HDR_OPCODE);
+	if (cmd != SMB2_OP_NEGPROT) {
+		DEBUG(0,("Invalid SMB packet: first request: 0x%04X\n",
+			 cmd));
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	next_command_ofs = IVAL(inhdr, SMB2_HDR_NEXT_COMMAND);
+	if (next_command_ofs != 0) {
+		DEBUG(0,("Invalid SMB packet: next_command: 0x%08X\n",
+			 next_command_ofs));
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	mem_pool = talloc_pool(conn, 8192);
+	if (mem_pool == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	req = talloc_zero(mem_pool, struct smbd_smb2_request);
+	if (req == NULL) {
+		talloc_free(mem_pool);
+		return NT_STATUS_NO_MEMORY;
+	}
+	req->mem_pool	= mem_pool;
+	req->conn	= conn;
+
+	talloc_steal(req, inbuf);
+
+	req->in.vector = talloc_array(req, struct iovec, 4);
+	if (req->in.vector == NULL) {
+		talloc_free(mem_pool);
+		return NT_STATUS_NO_MEMORY;
+	}
+	req->in.vector_count = 4;
+
+	memcpy(req->in.nbt_hdr, inbuf, 4);
+
+	ofs = 0;
+	req->in.vector[0].iov_base	= (void *)req->in.nbt_hdr;
+	req->in.vector[0].iov_len	= 4;
+	ofs += req->in.vector[0].iov_len;
+
+	req->in.vector[1].iov_base	= (void *)(inbuf + ofs);
+	req->in.vector[1].iov_len	= SMB2_HDR_BODY;
+	ofs += req->in.vector[1].iov_len;
+
+	req->in.vector[2].iov_base	= (void *)(inbuf + ofs);
+	req->in.vector[2].iov_len	= SVAL(inbuf, ofs) & 0xFFFE;
+	ofs += req->in.vector[2].iov_len;
+
+	if (ofs > size) {
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	req->in.vector[3].iov_base	= (void *)(inbuf + ofs);
+	req->in.vector[3].iov_len	= size - ofs;
+	ofs += req->in.vector[3].iov_len;
+
+	req->current_idx = 1;
+
+	*_req = req;
+	return NT_STATUS_OK;
+}
+
+static NTSTATUS smbd_smb2_request_setup_out(struct smbd_smb2_request *req)
+{
+	struct iovec *vector;
+	int count;
+	int idx;
+
+	count = req->in.vector_count;
+	vector = talloc_array(req, struct iovec, count);
+	if (vector == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	vector[0].iov_base	= req->out.nbt_hdr;
+	vector[0].iov_len	= 4;
+	SIVAL(req->out.nbt_hdr, 0, 0);
+
+	for (idx=1; idx < count; idx += 3) {
+		const uint8_t *inhdr = NULL;
+		uint8_t *outhdr = NULL;
+		uint8_t *outbody = NULL;
+		uint8_t *outdyn = NULL;
+		size_t outdyn_size = 1;
+		uint32_t next_command_ofs = 0;
+		struct iovec *current = &vector[idx];
+
+		if ((idx + 3) < count) {
+			/* we have a next command */
+			next_command_ofs = SMB2_HDR_BODY + 8 + 8;
+			outdyn_size = 8;
+		}
+
+		inhdr = (const uint8_t *)req->in.vector[idx].iov_base;
+
+		outhdr = talloc_array(vector, uint8_t,
+				      SMB2_HDR_BODY + 8 + outdyn_size);
+		if (outhdr == NULL) {
+			return NT_STATUS_NO_MEMORY;
+		}
+
+		outbody = outhdr + SMB2_HDR_BODY;
+		outdyn = outbody + 8;
+
+		current[0].iov_base	= (void *)outhdr;
+		current[0].iov_len	= SMB2_HDR_BODY;
+
+		current[1].iov_base	= (void *)outbody;
+		current[1].iov_len	= 8;
+
+		current[2].iov_base	= (void *)outdyn;
+		current[2].iov_len	= outdyn_size;
+
+		/* setup the SMB2 header */
+		SIVAL(outhdr, SMB2_HDR_PROTOCOL_ID,	SMB2_MAGIC);
+		SSVAL(outhdr, SMB2_HDR_LENGTH,		SMB2_HDR_BODY);
+		SSVAL(outhdr, SMB2_HDR_EPOCH,		0);
+		SIVAL(outhdr, SMB2_HDR_STATUS,
+		      NT_STATUS_V(NT_STATUS_INTERNAL_ERROR));
+		SSVAL(outhdr, SMB2_HDR_OPCODE,
+		      SVAL(inhdr, SMB2_HDR_OPCODE));
+		SSVAL(outhdr, SMB2_HDR_CREDIT,		0);
+		SIVAL(outhdr, SMB2_HDR_FLAGS,		SMB2_HDR_FLAG_REDIRECT);
+		SIVAL(outhdr, SMB2_HDR_NEXT_COMMAND,	next_command_ofs);
+		SIVAL(outhdr, SMB2_HDR_MESSAGE_ID,
+		      IVAL(inhdr, SMB2_HDR_MESSAGE_ID));
+		SIVAL(outhdr, SMB2_HDR_PID,
+		      IVAL(inhdr, SMB2_HDR_PID));
+		SIVAL(outhdr, SMB2_HDR_TID,
+		      IVAL(inhdr, SMB2_HDR_TID));
+		SIVAL(outhdr, SMB2_HDR_SESSION_ID,
+		      IVAL(inhdr, SMB2_HDR_SESSION_ID));
+		memset(outhdr + SMB2_HDR_SIGNATURE, 0, 16);
+
+		/* setup error body header */
+		SSVAL(outbody, 0x00, 9);
+		SSVAL(outbody, 0x02, 0);
+		SIVAL(outbody, 0x04, 0);
+
+		/* setup the dynamic part */
+		SCVAL(outdyn, 0x00, 0);
+	}
+
+	req->out.vector = vector;
+	req->out.vector_count = count;
+
+	/* setup the length of the NBT packet */
+	smb2_setup_nbt_length(req->out.vector, req->out.vector_count);
+
+	return NT_STATUS_OK;
+}
+
+static void smbd_server_connection_terminate(struct smbd_server_connection *conn,
+					     const char *reason)
+{
+	DEBUG(10,("smbd_server_connection_terminate: reason[%s]\n", reason));
+	exit_server_cleanly(reason);
+}
+
+static NTSTATUS smbd_smb2_request_dispatch(struct smbd_smb2_request *req)
+{
+	const uint8_t *inhdr;
+	int i = req->current_idx;
+	uint16_t opcode;
+
+	inhdr = (const uint8_t *)req->in.vector[i].iov_base;
+
+	/* TODO: verify more things */
+
+	opcode = IVAL(inhdr, SMB2_HDR_OPCODE);
+	DEBUG(10,("smbd_smb2_request_dispatch: opcode[%u]\n", opcode));
+	switch (opcode) {
+	case SMB2_OP_NEGPROT:
+	case SMB2_OP_SESSSETUP:
+	case SMB2_OP_LOGOFF:
+	case SMB2_OP_TCON:
+	case SMB2_OP_TDIS:
+	case SMB2_OP_CREATE:
+	case SMB2_OP_CLOSE:
+	case SMB2_OP_FLUSH:
+	case SMB2_OP_READ:
+	case SMB2_OP_WRITE:
+	case SMB2_OP_LOCK:
+	case SMB2_OP_IOCTL:
+	case SMB2_OP_CANCEL:
+	case SMB2_OP_KEEPALIVE:
+	case SMB2_OP_FIND:
+	case SMB2_OP_NOTIFY:
+	case SMB2_OP_GETINFO:
+	case SMB2_OP_SETINFO:
+	case SMB2_OP_BREAK:
+		return smbd_smb2_request_error(req, NT_STATUS_NOT_IMPLEMENTED);
+	}
+
+	return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
+}
+
+static void smbd_smb2_request_dispatch_compound(struct tevent_req *subreq);
+static void smbd_smb2_request_writev_done(struct tevent_req *subreq);
+
+static NTSTATUS smbd_smb2_request_reply(struct smbd_smb2_request *req)
+{
+	struct tevent_req *subreq;
+
+	/* TODO: sign the response here */
+
+	smb2_setup_nbt_length(req->out.vector, req->out.vector_count);
+
+	req->current_idx += 3;
+
+	if (req->current_idx > req->in.vector_count) {
+		struct timeval zero = timeval_zero();
+		subreq = tevent_wakeup_send(req,
+					    req->conn->smb2.event_ctx,
+					    zero);
+		if (subreq == NULL) {
+			return NT_STATUS_NO_MEMORY;
+		}
+		tevent_req_set_callback(subreq,
+					smbd_smb2_request_dispatch_compound,
+					req);
+
+		return NT_STATUS_OK;
+	}
+
+	subreq = tstream_writev_queue_send(req,
+					   req->conn->smb2.event_ctx,
+					   req->conn->smb2.stream,
+					   req->conn->smb2.send_queue,
+					   req->out.vector,
+					   req->out.vector_count);
+	if (subreq == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+	tevent_req_set_callback(subreq, smbd_smb2_request_writev_done, req);
+
+	return NT_STATUS_OK;
+}
+
+NTSTATUS smbd_smb2_request_error_ex(struct smbd_smb2_request *req,
+				    NTSTATUS status,
+				    DATA_BLOB *info)
+{
+	uint8_t *outhdr;
+	uint8_t *outbody;
+	int i = req->current_idx;
+
+	DEBUG(10,("smbd_smb2_request_error_ex: idx[%d] status[%s]%s\n",
+		  i, nt_errstr(status), info ? " +info" : ""));
+
+	outhdr = (uint8_t *)req->out.vector[i].iov_base;
+
+	SIVAL(outhdr, SMB2_HDR_STATUS, NT_STATUS_V(status));
+
+	outbody = outhdr + SMB2_HDR_BODY;
+
+	req->out.vector[i+1].iov_base = (void *)outbody;
+	req->out.vector[i+1].iov_len = 8;
+
+	if (info) {
+		SIVAL(outbody, 0x04, info->length);
+		req->out.vector[i+2].iov_base	= (void *)info->data;
+		req->out.vector[i+2].iov_len	= info->length;
+	} else {
+		req->out.vector[i+2].iov_base = (void *)(outbody + 8);
+		req->out.vector[i+2].iov_len = 1;
+	}
+
+	/* the error packet is the last response in the chain */
+	SIVAL(outhdr, SMB2_HDR_NEXT_COMMAND, 0);
+	req->out.vector_count = req->current_idx + 3;
+
+	return smbd_smb2_request_reply(req);
+}
+
+NTSTATUS smbd_smb2_request_error(struct smbd_smb2_request *req,
+				 NTSTATUS status)
+{
+	return smbd_smb2_request_error_ex(req, status, NULL);
+}
+
+NTSTATUS smbd_smb2_request_done(struct smbd_smb2_request *req,
+				DATA_BLOB body, DATA_BLOB *dyn)
+{
+	uint8_t *outhdr;
+	uint8_t *outdyn;
+	int i = req->current_idx;
+	uint32_t next_command_ofs;
+
+	DEBUG(10,("smbd_smb2_request_done: idx[%d] body[%u] dyn[%s:%u]\n",
+		  i, (unsigned int)body.length,
+		  dyn ? "yes": "no",
+		  (unsigned int)(dyn ? dyn->length : 0)));
+
+	if (body.length < 2) {
+		return smbd_smb2_request_error(req, NT_STATUS_INTERNAL_ERROR);
+	}
+
+	if ((body.length % 2) != 0) {
+		return smbd_smb2_request_error(req, NT_STATUS_INTERNAL_ERROR);
+	}
+
+	outhdr = (uint8_t *)req->out.vector[i].iov_base;
+	/* the fallback dynamic buffer */
+	outdyn = outhdr + SMB2_HDR_BODY + 8;
+
+	next_command_ofs = SIVAL(outhdr, SMB2_HDR_NEXT_COMMAND, 0);
+	SIVAL(outhdr, SMB2_HDR_STATUS, NT_STATUS_V(NT_STATUS_OK));
+
+	req->out.vector[i+1].iov_base = (void *)body.data;
+	req->out.vector[i+1].iov_len = body.length;
+
+	if (dyn) {
+		if (dyn->length > 0) {
+			req->out.vector[i+2].iov_base	= (void *)dyn->data;
+			req->out.vector[i+2].iov_len	= dyn->length;
+		} else {
+			req->out.vector[i+2].iov_base	= (void *)outdyn;
+			req->out.vector[i+2].iov_len	= 1;
+		}
+	} else {
+		req->out.vector[i+2].iov_base = NULL;
+		req->out.vector[i+2].iov_len = 0;
+	}
+
+	/* see if we need to recalculate the offset to the next response */
+	if (next_command_ofs > 0) {
+		next_command_ofs  = SMB2_HDR_BODY;
+		next_command_ofs += req->out.vector[i+1].iov_len;
+		next_command_ofs += req->out.vector[i+2].iov_len;
+	}
+
+	/* TODO: we need to add padding ... */
+	if ((next_command_ofs % 8) != 0) {
+		return smbd_smb2_request_error(req, NT_STATUS_INTERNAL_ERROR);
+	}
+
+	/* the error packet is the last response in the chain */
+	SIVAL(outhdr, SMB2_HDR_NEXT_COMMAND, next_command_ofs);
+
+	return smbd_smb2_request_reply(req);
+}
+
+static void smbd_smb2_request_dispatch_compound(struct tevent_req *subreq)
+{
+	struct smbd_smb2_request *req = tevent_req_callback_data(subreq,
+					struct smbd_smb2_request);
+	struct smbd_server_connection *conn = req->conn;
+	NTSTATUS status;
+
+	tevent_wakeup_recv(subreq);
+	TALLOC_FREE(subreq);
+
+	DEBUG(10,("smbd_smb2_request_dispatch_compound: idx[%d] of %d vectors\n",
+		  req->current_idx, req->in.vector_count));
+
+	status = smbd_smb2_request_dispatch(req);
+	if (!NT_STATUS_IS_OK(status)) {
+		smbd_server_connection_terminate(conn, nt_errstr(status));
+		return;
+	}
+}
+
+static void smbd_smb2_request_writev_done(struct tevent_req *subreq)
+{
+	struct smbd_smb2_request *req = tevent_req_callback_data(subreq,
+					struct smbd_smb2_request);
+	struct smbd_server_connection *conn = req->conn;
+	int ret;
+	int sys_errno;
+	TALLOC_CTX *mem_pool;
+
+	ret = tstream_writev_queue_recv(subreq, &sys_errno);
+	TALLOC_FREE(subreq);
+	if (ret == -1) {
+		NTSTATUS status = map_nt_error_from_unix(sys_errno);
+		smbd_server_connection_terminate(conn, nt_errstr(status));
+		return;
+	}
+
+	mem_pool = req->mem_pool;
+	req = NULL;
+	talloc_free(mem_pool);
+}
+
+struct smbd_smb2_request_read_state {
+	size_t missing;
+	bool asked_for_header;
+	struct smbd_smb2_request *smb2_req;
+};
+
+static int smbd_smb2_request_next_vector(struct tstream_context *stream,
+					 void *private_data,
+					 TALLOC_CTX *mem_ctx,
+					 struct iovec **_vector,
+					 size_t *_count);
+static void smbd_smb2_request_read_done(struct tevent_req *subreq);
+
+static struct tevent_req *smbd_smb2_request_read_send(TALLOC_CTX *mem_ctx,
+					struct tevent_context *ev,
+					struct smbd_server_connection *conn)
+{
+	struct tevent_req *req;
+	struct smbd_smb2_request_read_state *state;
+	struct tevent_req *subreq;
+	TALLOC_CTX *mem_pool;
+
+	req = tevent_req_create(mem_ctx, &state,
+				struct smbd_smb2_request_read_state);
+	if (req == NULL) {
+		return NULL;
+	}
+	state->missing = 0;
+	state->asked_for_header = false;
+
+	mem_pool = talloc_pool(state, 8192);
+	if (tevent_req_nomem(mem_pool, req)) {
+		return tevent_req_post(req, ev);
+	}
+
+	state->smb2_req = talloc_zero(mem_pool, struct smbd_smb2_request);
+	if (tevent_req_nomem(state->smb2_req, req)) {
+		return tevent_req_post(req, ev);
+	}
+
+	state->smb2_req->mem_pool	= mem_pool;
+	state->smb2_req->conn		= conn;
+
+	subreq = tstream_readv_pdu_queue_send(state, ev, conn->smb2.stream,
+					      conn->smb2.recv_queue,
+					      smbd_smb2_request_next_vector,
+					      state);
+	if (tevent_req_nomem(subreq, req)) {
+		return tevent_req_post(req, ev);
+	}
+	tevent_req_set_callback(subreq, smbd_smb2_request_read_done, req);
+
+	return req;
+}
+
+static int smbd_smb2_request_next_vector(struct tstream_context *stream,
+					 void *private_data,
+					 TALLOC_CTX *mem_ctx,
+					 struct iovec **_vector,
+					 size_t *_count)
+{
+	struct smbd_smb2_request_read_state *state =
+		talloc_get_type_abort(private_data,
+		struct smbd_smb2_request_read_state);
+	struct smbd_smb2_request *req = state->smb2_req;
+	struct iovec *vector;
+	int idx = req->in.vector_count;
+	size_t len = 0;
+	uint8_t *buf = NULL;
+
+	if (req->in.vector_count == 0) {
+		/*
+		 * first we need to get the NBT header
+		 */
+		req->in.vector = talloc_array(req, struct iovec,
+					      req->in.vector_count + 1);
+		if (req->in.vector == NULL) {
+			return -1;
+		}
+		req->in.vector_count += 1;
+
+		req->in.vector[idx].iov_base	= (void *)req->in.nbt_hdr;
+		req->in.vector[idx].iov_len	= 4;
+
+		vector = talloc_array(mem_ctx, struct iovec, 1);
+		if (vector == NULL) {
+			return -1;
+		}
+
+		vector[0] = req->in.vector[idx];
+
+		*_vector = vector;
+		*_count = 1;
+		return 0;
+	}
+
+	if (req->in.vector_count == 1) {
+		/*
+		 * Now we analyze the NBT header
+		 */
+		state->missing = smb2_len(req->in.vector[0].iov_base);
+
+		if (state->missing == 0) {
+			/* if there're no remaining bytes, we're done */
+			*_vector = NULL;
+			*_count = 0;
+			return 0;
+		}
+
+		req->in.vector = talloc_realloc(req, req->in.vector,
+						struct iovec,
+						req->in.vector_count + 1);
+		if (req->in.vector == NULL) {
+			return -1;
+		}
+		req->in.vector_count += 1;
+
+		if (CVAL(req->in.vector[0].iov_base, 0) != 0) {
+			/*
+			 * it's a special NBT message,
+			 * so get all remaining bytes
+			 */
+			len = state->missing;
+		} else if (state->missing < (SMB2_HDR_BODY + 2)) {
+			/*
+			 * it's an invalid message, just read what we can get
+			 * and let the caller handle the error
+			 */
+			len = state->missing;
+		} else {
+			/*
+			 * We assume it's a SMB2 request,
+			 * and we first get the header and the
+			 * first 2 bytes (the struct size) of the body
+			 */
+			len = SMB2_HDR_BODY + 2;
+
+			state->asked_for_header = true;
+		}
+
+		state->missing -= len;
+
+		buf = talloc_array(req->in.vector, uint8_t, len);
+		if (buf == NULL) {
+			return -1;
+		}
+
+		req->in.vector[idx].iov_base	= (void *)buf;
+		req->in.vector[idx].iov_len	= len;
+
+		vector = talloc_array(mem_ctx, struct iovec, 1);
+		if (vector == NULL) {
+			return -1;
+		}
+
+		vector[0] = req->in.vector[idx];
+
+		*_vector = vector;
+		*_count = 1;
+		return 0;
+	}
+
+	if (state->missing == 0) {
+		/* if there're no remaining bytes, we're done */
+		*_vector = NULL;
+		*_count = 0;
+		return 0;
+	}
+
+	if (state->asked_for_header) {
+		const uint8_t *hdr;
+		size_t full_size;
+		size_t next_command_ofs;
+		size_t body_size;
+		uint8_t *body;
+		size_t dyn_size;
+		uint8_t *dyn;
+		bool invalid = false;
+
+		state->asked_for_header = false;
+
+		/*
+		 * We got the SMB2 header and the first 2 bytes
+		 * of the body. We fix the size to just the header
+		 * and manually copy the 2 first bytes to the body section
+		 */
+		req->in.vector[idx-1].iov_len = SMB2_HDR_BODY;
+		hdr = (const uint8_t *)req->in.vector[idx-1].iov_base;
+
+		/* allocate vectors for body and dynamic areas */
+		req->in.vector = talloc_realloc(req, req->in.vector,
+						struct iovec,
+						req->in.vector_count + 2);
+		if (req->in.vector == NULL) {
+			return -1;
+		}
+		req->in.vector_count += 2;
+
+		full_size = state->missing + SMB2_HDR_BODY + 2;
+		next_command_ofs = IVAL(hdr, SMB2_HDR_NEXT_COMMAND);
+		body_size = SVAL(hdr, SMB2_HDR_BODY);
+
+		if (next_command_ofs != 0) {
+			if (next_command_ofs < (SMB2_HDR_BODY + 2)) {
+				/*
+				 * this is invalid, just return a zero
+				 * body and let the caller deal with the error
+				 */
+				invalid = true;
+			} else if (next_command_ofs > full_size) {
+				/*
+				 * this is invalid, just return a zero
+				 * body and let the caller deal with the error
+				 */
+				invalid = true;
+			} else {
+				full_size = next_command_ofs;
+			}
+		}
+
+		if (!invalid) {
+			if (body_size < 2) {
+				/*
+				 * this is invalid, just return a zero
+				 * body and let the caller deal with the error
+				 */
+				invalid = true;
+			} else if (body_size > (full_size - SMB2_HDR_BODY)) {
+				/*
+				 * this is invalid, just return a zero
+				 * body and let the caller deal with the error
+				 */
+				invalid = true;
+			}
+		}
+
+		if (invalid) {
+			/* the caller should check this */
+			body_size = 0;
+		}
+
+		if ((body_size % 2) != 0) {
+			body_size -= 1;
+		}
+
+		dyn_size = full_size - (SMB2_HDR_BODY + body_size);
+
+		state->missing -= (body_size - 2) + dyn_size;
+
+		body = talloc_array(req->in.vector, uint8_t, body_size);
+		if (body == NULL) {
+			return -1;
+		}
+
+		dyn = talloc_array(req->in.vector, uint8_t, dyn_size);
+		if (dyn == NULL) {
+			return -1;
+		}
+
+		req->in.vector[idx].iov_base	= (void *)body;
+		req->in.vector[idx].iov_len	= body_size;
+		req->in.vector[idx+1].iov_base	= (void *)dyn;
+		req->in.vector[idx+1].iov_len	= dyn_size;
+
+		vector = talloc_array(mem_ctx, struct iovec, 2);
+		if (vector == NULL) {
+			return -1;
+		}
+
+		/*
+		 * the first 2 bytes of the body were already fetched
+		 * together with the header
+		 */
+		memcpy(body, hdr + SMB2_HDR_BODY, 2);
+		vector[0].iov_base = body + 2;
+		vector[0].iov_len = req->in.vector[idx].iov_len - 2;
+
+		vector[1] = req->in.vector[idx+1];
+
+		*_vector = vector;
+		*_count = 2;
+		return 0;
+	}
+
+	/*
+	 * when we endup here, we're looking for a new SMB2 request
+	 * next. And we ask for its header and the first 2 bytes of
+	 * the body (like we did for the first SMB2 request).
+	 */
+
+	req->in.vector = talloc_realloc(req, req->in.vector,
+					struct iovec,
+					req->in.vector_count + 1);
+	if (req->in.vector == NULL) {
+		return -1;
+	}
+	req->in.vector_count += 1;
+
+	/*
+	 * We assume it's a SMB2 request,
+	 * and we first get the header and the
+	 * first 2 bytes (the struct size) of the body
+	 */
+	len = SMB2_HDR_BODY + 2;
+
+	if (len > state->missing) {
+		/* let the caller handle the error */
+		len = state->missing;
+	}
+
+	state->missing -= len;
+	state->asked_for_header = true;
+
+	buf = talloc_array(req->in.vector, uint8_t, len);
+	if (buf == NULL) {
+		return -1;
+	}
+
+	req->in.vector[idx].iov_base	= (void *)buf;
+	req->in.vector[idx].iov_len	= len;
+
+	vector = talloc_array(mem_ctx, struct iovec, 1);
+	if (vector == NULL) {
+		return -1;
+	}
+
+	vector[0] = req->in.vector[idx];
+
+	*_vector = vector;
+	*_count = 1;
+	return 0;
+}
+
+static void smbd_smb2_request_read_done(struct tevent_req *subreq)
+{
+	struct tevent_req *req =
+		tevent_req_callback_data(subreq,
+		struct tevent_req);
+	int ret;
+	int sys_errno;
+	NTSTATUS status;
+
+	ret = tstream_readv_pdu_queue_recv(subreq, &sys_errno);
+	if (ret == -1) {
+		status = map_nt_error_from_unix(sys_errno);
+		tevent_req_nterror(req, status);
+		return;
+	}
+
+	tevent_req_done(req);
+}
+
+static NTSTATUS smbd_smb2_request_read_recv(struct tevent_req *req,
+					    TALLOC_CTX *mem_ctx,
+					    struct smbd_smb2_request **_smb2_req)
+{
+	struct smbd_smb2_request_read_state *state =
+		tevent_req_data(req,
+		struct smbd_smb2_request_read_state);
+	NTSTATUS status;
+
+	if (tevent_req_is_nterror(req, &status)) {
+		tevent_req_received(req);
+		return status;
+	}
+
+	talloc_steal(mem_ctx, state->smb2_req->mem_pool);
+	*_smb2_req = state->smb2_req;
+	tevent_req_received(req);
+	return NT_STATUS_OK;
+}
+
+static void smbd_smb2_request_incoming(struct tevent_req *subreq);
+
+void smbd_smb2_first_negprot(struct smbd_server_connection *conn,
+			     const uint8_t *inbuf, size_t size)
+{
+	NTSTATUS status;
+	struct smbd_smb2_request *req;
+	struct tevent_req *subreq;
+
+	DEBUG(10,("smbd_smb2_first_negprot: packet length %u\n",
+		 (unsigned int)size));
+
+	status = smbd_initialize_smb2(conn);
+	if (!NT_STATUS_IS_OK(status)) {
+		smbd_server_connection_terminate(conn, nt_errstr(status));
+		return;
+	}
+
+	status = smbd_smb2_request_create(conn, inbuf, size, &req);
+	if (!NT_STATUS_IS_OK(status)) {
+		smbd_server_connection_terminate(conn, nt_errstr(status));
+		return;
+	}
+
+	status = smbd_smb2_request_setup_out(req);
+	if (!NT_STATUS_IS_OK(status)) {
+		smbd_server_connection_terminate(conn, nt_errstr(status));
+		return;
+	}
+
+	status = smbd_smb2_request_dispatch(req);
+	if (!NT_STATUS_IS_OK(status)) {
+		smbd_server_connection_terminate(conn, nt_errstr(status));
+		return;
+	}
+
+	/* ask for the next request */
+	subreq = smbd_smb2_request_read_send(conn,conn->smb2.event_ctx, conn);
+	if (subreq == NULL) {
+		smbd_server_connection_terminate(conn, "no memory for reading");
+		return;
+	}
+	tevent_req_set_callback(subreq, smbd_smb2_request_incoming, conn);
+}
+
+static void smbd_smb2_request_incoming(struct tevent_req *subreq)
+{
+	struct smbd_server_connection *conn = tevent_req_callback_data(subreq,
+					      struct smbd_server_connection);
+	NTSTATUS status;
+	struct smbd_smb2_request *req;
+
+	status = smbd_smb2_request_read_recv(subreq, conn, &req);
+	TALLOC_FREE(subreq);
+	if (!NT_STATUS_IS_OK(status)) {
+		smbd_server_connection_terminate(conn, nt_errstr(status));
+		return;
+	}
+
+	/* TODO: validate the incoming request */
+	req->current_idx = 1;
+
+	DEBUG(10,("smbd_smb2_request_incoming: idx[%d] of %d vectors\n",
+		 req->current_idx, req->in.vector_count));
+
+	status = smbd_smb2_request_setup_out(req);
+	if (!NT_STATUS_IS_OK(status)) {
+		smbd_server_connection_terminate(conn, nt_errstr(status));
+		return;
+	}
+
+	status = smbd_smb2_request_dispatch(req);
+	if (!NT_STATUS_IS_OK(status)) {
+		smbd_server_connection_terminate(conn, nt_errstr(status));
+		return;
+	}
+
+	/* ask for the next request (this constructs the main loop) */
+	subreq = smbd_smb2_request_read_send(conn,conn->smb2.event_ctx, conn);
+	if (subreq == NULL) {
+		smbd_server_connection_terminate(conn, "no memory for reading");
+		return;
+	}
+	tevent_req_set_callback(subreq, smbd_smb2_request_incoming, conn);
+}