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/*********************************************************
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* Copyright (C) 2011 VMware, Inc. All rights reserved.
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by the
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* Free Software Foundation version 2 and no later version.
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write to the Free Software Foundation, Inc.,
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* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*********************************************************/
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* Implementation of VMCI routing rules.
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#include "vmci_kernel_if.h"
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#include "vm_assert.h"
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#include "vmci_defs.h"
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#include "vmci_infrastructure.h"
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#include "vmciCommonInt.h"
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#include "vmciContext.h"
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#include "vmciDriver.h"
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#include "vmciKernelAPI.h"
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#include "vmciRoute.h"
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# include "vmciVmkInt.h"
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# include "helper_ext.h"
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#define LGPFX "VMCIRoute: "
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*------------------------------------------------------------------------------
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* Make a routing decision for the given source and destination handles.
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* This will try to determine the route using the handles and the available
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* Sets the source context if it is invalid.
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*------------------------------------------------------------------------------
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VMCI_Route(VMCIHandle *src, // IN/OUT
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const VMCIHandle *dst, // IN
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VMCIRoute *route) // OUT
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*route = VMCI_ROUTE_NONE;
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* "fromGuest" is only ever set to TRUE by IOCTL_VMCI_DATAGRAM_SEND (or by
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* the vmkernel equivalent), which comes from the VMX, so we know it is
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* coming from a guest.
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* To avoid inconsistencies, test these once. We will test them again
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* when we do the actual send to ensure that we do not touch a non-existent
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hasHostDevice = VMCI_HostPersonalityActive();
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hasGuestDevice = VMCI_GuestPersonalityActive();
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/* Must have a valid destination context. */
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if (VMCI_INVALID_ID == dst->context) {
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return VMCI_ERROR_INVALID_ARGS;
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* If we are acting as a host and the datagram is from or for a well-known
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* context (which also means it must have been passed down from a guest),
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* then we can assume it is intended for a guest on this host.
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if (fromGuest && hasHostDevice &&
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(VMCI_WELL_KNOWN_CONTEXT_ID == src->context ||
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VMCI_WELL_KNOWN_CONTEXT_ID == dst->context)) {
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*route = VMCI_ROUTE_AS_HOST;
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/* Anywhere to hypervisor. */
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if (VMCI_HYPERVISOR_CONTEXT_ID == dst->context) {
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* If this message already came from a guest then we cannot send it
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* to the hypervisor. It must come from a local client.
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return VMCI_ERROR_DST_UNREACHABLE;
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/* We must be acting as a guest in order to send to the hypervisor. */
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if (!hasGuestDevice) {
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return VMCI_ERROR_DEVICE_NOT_FOUND;
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/* And we cannot send if the source is the host context. */
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if (VMCI_HOST_CONTEXT_ID == src->context) {
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return VMCI_ERROR_INVALID_ARGS;
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/* Send from local client down to the hypervisor. */
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*route = VMCI_ROUTE_AS_GUEST;
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/* Anywhere to local client on host. */
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if (VMCI_HOST_CONTEXT_ID == dst->context) {
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* If it is not from a guest but we are acting as a guest, then we need
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* to send it down to the host. Note that if we are also acting as a
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* host then this will prevent us from sending from local client to
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* local client, but we accept that restriction as a way to remove
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* any ambiguity from the host context.
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if (src->context == VMCI_HYPERVISOR_CONTEXT_ID) {
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* If the hypervisor is the source, this is host local
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* communication. The hypervisor may send vmci event
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* datagrams to the host itself, but it will never send
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* datagrams to an "outer host" through the guest device.
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*route = VMCI_ROUTE_AS_HOST;
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return VMCI_ERROR_DEVICE_NOT_FOUND;
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if (!fromGuest && hasGuestDevice) {
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/* If no source context then use the current. */
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if (VMCI_INVALID_ID == src->context) {
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src->context = VMCI_GetContextID();
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/* Send it from local client down to the host. */
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*route = VMCI_ROUTE_AS_GUEST;
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* Otherwise we already received it from a guest and it is destined
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* for a local client on this host, or it is from another local client
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* on this host. We must be acting as a host to service it.
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if (!hasHostDevice) {
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return VMCI_ERROR_DEVICE_NOT_FOUND;
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if (VMCI_INVALID_ID == src->context) {
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* If it came from a guest then it must have a valid context.
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* Otherwise we can use the host context.
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return VMCI_ERROR_INVALID_ARGS;
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src->context = VMCI_HOST_CONTEXT_ID;
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/* Route to local client. */
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*route = VMCI_ROUTE_AS_HOST;
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/* If we are acting as a host then this might be destined for a guest. */
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/* It will have a context if it is meant for a guest. */
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if (VMCIContext_Exists(dst->context)) {
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if (VMCI_INVALID_ID == src->context) {
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* If it came from a guest then it must have a valid context.
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* Otherwise we can use the host context.
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return VMCI_ERROR_INVALID_ARGS;
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src->context = VMCI_HOST_CONTEXT_ID;
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/* Pass it up to the guest. */
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*route = VMCI_ROUTE_AS_HOST;
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* We must be a guest trying to send to another guest, which means we
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* need to send it down to the host.
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if (!hasGuestDevice) {
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return VMCI_ERROR_DEVICE_NOT_FOUND;
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/* If no source context then use the current context. */
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if (VMCI_INVALID_ID == src->context) {
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src->context = VMCI_GetContextID();
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* Send it from local client down to the host, which will route it to
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* the other guest for us.
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*route = VMCI_ROUTE_AS_GUEST;
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*------------------------------------------------------------------------------
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* VMCI_RouteString --
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* Get a string for the given route.
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* A string representing the route, if the route is valid, otherwise an
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*------------------------------------------------------------------------------
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VMCI_RouteString(VMCIRoute route) // IN
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const char *vmciRouteStrings[] = {
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if (route >= VMCI_ROUTE_NONE && route <= VMCI_ROUTE_AS_GUEST) {
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return vmciRouteStrings[route];
added
removed
modules/linux/vmci/common/vmciRoute.c
