External/passt
1
0
Fork 0
mirror of https://passt.top/passt synced 2024-06-30 23:12:39 +00:00
Code Issues Packages Projects Releases Wiki Activity

passt: Add libvirt patch for qemu UNIX socket domain back-end

Browse Source 
...and mention it in the README.

While at it, remove useless escaping in the README, and fix
indentation in the syslog message with the qemu command line
example.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
This commit is contained in:
Stefano Brivio 2021-03-20 07:22:09 +01:00
parent 35015ce72e
commit e653f9b3ed
3 changed files with 438 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
README.md
View File

@ -5,6 +5,8 @@ and native Layer-4 sockets (TCP, UDP, ICMP/ICMPv6 echo) on a host. It doesn't
require any capabilities or privileges, and it can be used as a simple
replacement for Slirp.
![overview diagram](/builds/passt_overview.png)
- [General idea](#general-idea)
- [Non-functional Targets](#non-functional-targets)
- [Interfaces and Environment](#interfaces-and-environment)
@ -50,7 +52,7 @@ solution comes with a number of downsides:
_passt_ implements a thinner layer between guest and host, that only implements
what's strictly needed to pretend processes are running locally. A further, full
TCP/IP stack is not necessarily needed. Some sort of TCP adaptation is needed,
however, as this layer runs without the `CAP\_NET\_RAW` capability: we can't
however, as this layer runs without the `CAP_NET_RAW` capability: we can't
create raw IP sockets on the pod, and therefore need to map packets at Layer-2
to Layer-4 sockets offered by the host kernel.
@ -163,6 +165,17 @@ before _passt_ starts.
qemu-system-x86_64 ... -net socket,connect=/tmp/passt.socket -net nic,model=virtio
* alternatively, you can use libvirt, with [this patch](https://passt.top/passt/tree/libvirt/0001-conf-Introduce-support-for-UNIX-domain-socket-as-qem.patch),
to start qemu (with the patch mentioned above), with this kind of network
interface configuration:
<interface type='client'>
<mac address='52:54:00:02:6b:60'/>
<source path='/tmp/passt.socket'/>
<model type='virtio'/>
<address type='pci' domain='0x0000' bus='0x01' slot='0x00' function='0x0'/>
</interface>
* and that's it, you should now have TCP connections, UDP, and ICMP/ICMPv6
echo working from/to the guest for IPv4 and IPv6

423
libvirt/0001-conf-Introduce-support-for-UNIX-domain-socket-as-qem.patch Normal file
View File

@ -0,0 +1,423 @@
From 62e95cb4b5708eca7860139dffef22e65b29514c Mon Sep 17 00:00:00 2001
From: Stefano Brivio <sbrivio@redhat.com>
Date: Sat, 20 Mar 2021 07:16:15 +0100
Subject: [PATCH] conf: Introduce support for UNIX domain socket as qemu netdev
back-end
Since qemu [TODO], named UNIX domain sockets can be used instead of
TCP to establish a virtual network between VMs.
The obvious difference compared with TCP is that we need pass a path
instead of address and port.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
---
docs/formatdomain.rst | 41 +++++++++++++++++++------
docs/schemas/domaincommon.rng | 50 +++++++++++++++++++++++-------
src/conf/domain_conf.c | 58 +++++++++++++++++++++++++++--------
src/conf/domain_conf.h | 13 +++++---
src/qemu/qemu_command.c | 46 ++++++++++++++++++---------
src/qemu/qemu_hotplug.c | 8 +++--
6 files changed, 160 insertions(+), 56 deletions(-)
diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst
index 9392c80113..b5b642e91a 100644
--- a/docs/formatdomain.rst
+++ b/docs/formatdomain.rst
@@ -4995,18 +4995,20 @@ must be from the multicast address block.
</devices>
...
-:anchor:`<a id="elementsNICSTCP"/>`
+:anchor:`<a id="elementsNICSStream"/>`
-TCP tunnel
-^^^^^^^^^^
+TCP or UNIX domain socket tunnel
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+A stream-oriented client/server architecture provides a virtual network. One VM
+provides the server end of the network, all other VMS are configured as clients.
+All network traffic is routed between the VMs via the server. This mode is also
+available to unprivileged users. There is no default DNS or DHCP support and no
+outgoing network access. To provide outgoing network access, one of the VMs
+should have a 2nd NIC which is connected to one of the first 4 network types and
+do the appropriate routing.
-A TCP client/server architecture provides a virtual network. One VM provides the
-server end of the network, all other VMS are configured as clients. All network
-traffic is routed between the VMs via the server. This mode is also available to
-unprivileged users. There is no default DNS or DHCP support and no outgoing
-network access. To provide outgoing network access, one of the VMs should have a
-2nd NIC which is connected to one of the first 4 network types and do the
-appropriate routing.
+TCP endpoints can be specified as follows:
::
@@ -5024,6 +5026,25 @@ appropriate routing.
</devices>
...
+Named UNIX domain sockets can be specified as follows:
+:since:`Since 7.2.0, qemu`
+
+::
+
+ ...
+ <devices>
+ <interface type='server'>
+ <mac address='52:54:00:22:c9:42'/>
+ <source path='/tmp/qemu.socket'/>
+ </interface>
+ ...
+ <interface type='client'>
+ <mac address='52:54:00:8b:c9:51'/>
+ <source path='/tmp/qemu.socket'/>
+ </interface>
+ </devices>
+ ...
+
:anchor:`<a id="elementsNICSUDP"/>`
UDP unicast tunnel
diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng
index 1dbfc68f18..350d6969c0 100644
--- a/docs/schemas/domaincommon.rng
+++ b/docs/schemas/domaincommon.rng
@@ -3125,10 +3125,7 @@
</group>
<group>
<attribute name="type">
- <choice>
- <value>mcast</value>
- <value>client</value>
- </choice>
+ <value>mcast</value>
</attribute>
<interleave>
<element name="source">
@@ -3143,6 +3140,30 @@
<ref name="interface-options"/>
</interleave>
</group>
+ <group>
+ <attribute name="type">
+ <value>client</value>
+ </attribute>
+ <interleave>
+ <element name="source">
+ <choice>
+ <group>
+ <attribute name="address">
+ <ref name="ipv4Addr"/>
+ </attribute>
+ <attribute name="port">
+ <ref name="PortNumber"/>
+ </attribute>
+ </group>
+ <attribute name="path">
+ <ref name="absFilePath"/>
+ </attribute>
+ </choice>
+ <empty/>
+ </element>
+ <ref name="interface-options"/>
+ </interleave>
+ </group>
<group>
<attribute name="type">
<value>udp</value>
@@ -3174,14 +3195,21 @@
</attribute>
<interleave>
<element name="source">
- <optional>
- <attribute name="address">
- <ref name="ipv4Addr"/>
+ <choice>
+ <group>
+ <optional>
+ <attribute name="address">
+ <ref name="ipv4Addr"/>
+ </attribute>
+ </optional>
+ <attribute name="port">
+ <ref name="PortNumber"/>
+ </attribute>
+ </group>
+ <attribute name="path">
+ <ref name="absFilePath"/>
</attribute>
- </optional>
- <attribute name="port">
- <ref name="PortNumber"/>
- </attribute>
+ </choice>
<empty/>
</element>
<ref name="interface-options"/>
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 7671050134..55543c47ce 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -2569,8 +2569,9 @@ virDomainNetDefFree(virDomainNetDefPtr def)
case VIR_DOMAIN_NET_TYPE_CLIENT:
case VIR_DOMAIN_NET_TYPE_MCAST:
case VIR_DOMAIN_NET_TYPE_UDP:
- g_free(def->data.socket.address);
- g_free(def->data.socket.localaddr);
+ g_free(def->data.socket.net.address);
+ g_free(def->data.socket.net.localaddr);
+ g_free(def->data.socket.path);
break;
case VIR_DOMAIN_NET_TYPE_NETWORK:
@@ -10792,6 +10793,7 @@ virDomainNetDefParseXML(virDomainXMLOptionPtr xmlopt,
g_autofree char *downscript = NULL;
g_autofree char *address = NULL;
g_autofree char *port = NULL;
+ g_autofree char *path = NULL;
g_autofree char *localaddr = NULL;
g_autofree char *localport = NULL;
g_autofree char *model = NULL;
@@ -10935,7 +10937,7 @@ virDomainNetDefParseXML(virDomainXMLOptionPtr xmlopt,
" <interface type='%s'>"), type);
goto error;
}
- } else if (!address &&
+ } else if (!address && !path &&
(def->type == VIR_DOMAIN_NET_TYPE_SERVER ||
def->type == VIR_DOMAIN_NET_TYPE_CLIENT ||
def->type == VIR_DOMAIN_NET_TYPE_MCAST ||
@@ -10943,6 +10945,7 @@ virDomainNetDefParseXML(virDomainXMLOptionPtr xmlopt,
virXMLNodeNameEqual(cur, "source")) {
address = virXMLPropString(cur, "address");
port = virXMLPropString(cur, "port");
+ path = virXMLPropString(cur, "path");
if (!localaddr && def->type == VIR_DOMAIN_NET_TYPE_UDP) {
xmlNodePtr tmpnode = ctxt->node;
ctxt->node = cur;
@@ -11186,6 +11189,27 @@ virDomainNetDefParseXML(virDomainXMLOptionPtr xmlopt,
case VIR_DOMAIN_NET_TYPE_CLIENT:
case VIR_DOMAIN_NET_TYPE_SERVER:
+ if (path != NULL) {
+ if (port != NULL || address != NULL ||
+ localport != NULL || localaddr != NULL) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("<source> 'path' attribute "
+ "for socket interface cannot be specified "
+ "together with other attributes"));
+ goto error;
+ }
+ def->data.socket.path = g_steal_pointer(&path);
+ break;
+ }
+
+ if (port == NULL) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Neither <source> 'port' nor 'path' attribute "
+ "specified with socket interface"));
+ goto error;
+ }
+
+ G_GNUC_FALLTHROUGH;
case VIR_DOMAIN_NET_TYPE_MCAST:
case VIR_DOMAIN_NET_TYPE_UDP:
if (port == NULL) {
@@ -11194,7 +11218,7 @@ virDomainNetDefParseXML(virDomainXMLOptionPtr xmlopt,
"specified with socket interface"));
goto error;
}
- if (virStrToLong_i(port, NULL, 10, &def->data.socket.port) < 0) {
+ if (virStrToLong_i(port, NULL, 10, &def->data.socket.net.port) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("Cannot parse <source> 'port' attribute "
"with socket interface"));
@@ -11211,7 +11235,7 @@ virDomainNetDefParseXML(virDomainXMLOptionPtr xmlopt,
goto error;
}
} else {
- def->data.socket.address = g_steal_pointer(&address);
+ def->data.socket.net.address = g_steal_pointer(&address);
}
if (def->type != VIR_DOMAIN_NET_TYPE_UDP)
@@ -11223,7 +11247,8 @@ virDomainNetDefParseXML(virDomainXMLOptionPtr xmlopt,
"specified with socket interface"));
goto error;
}
- if (virStrToLong_i(localport, NULL, 10, &def->data.socket.localport) < 0) {
+ if (virStrToLong_i(localport, NULL, 10,
+ &def->data.socket.net.localport) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("Cannot parse <local> 'port' attribute "
"with socket interface"));
@@ -11236,7 +11261,7 @@ virDomainNetDefParseXML(virDomainXMLOptionPtr xmlopt,
"specified with socket interface"));
goto error;
} else {
- def->data.socket.localaddr = g_steal_pointer(&localaddr);
+ def->data.socket.net.localaddr = g_steal_pointer(&localaddr);
}
break;
@@ -26219,15 +26244,22 @@ virDomainNetDefFormat(virBufferPtr buf,
case VIR_DOMAIN_NET_TYPE_SERVER:
case VIR_DOMAIN_NET_TYPE_CLIENT:
+ if (def->data.socket.path) {
+ virBufferAsprintf(buf, "<source path='%s'",
+ def->data.socket.path);
+ sourceLines++;
+ break;
+ }
+ G_GNUC_FALLTHROUGH;
case VIR_DOMAIN_NET_TYPE_MCAST:
case VIR_DOMAIN_NET_TYPE_UDP:
- if (def->data.socket.address) {
+ if (def->data.socket.net.address) {
virBufferAsprintf(buf, "<source address='%s' port='%d'",
- def->data.socket.address,
- def->data.socket.port);
+ def->data.socket.net.address,
+ def->data.socket.net.port);
} else {
virBufferAsprintf(buf, "<source port='%d'",
- def->data.socket.port);
+ def->data.socket.net.port);
}
sourceLines++;
@@ -26239,8 +26271,8 @@ virDomainNetDefFormat(virBufferPtr buf,
virBufferAdjustIndent(buf, 2);
virBufferAsprintf(buf, "<local address='%s' port='%d'/>\n",
- def->data.socket.localaddr,
- def->data.socket.localport);
+ def->data.socket.net.localaddr,
+ def->data.socket.net.localport);
virBufferAdjustIndent(buf, -2);
break;
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index 87bc7e8625..3cc0842eed 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -1042,11 +1042,14 @@ struct _virDomainNetDef {
virDomainNetTeamingInfoPtr teaming;
union {
virDomainChrSourceDefPtr vhostuser;
- struct {
- char *address;
- int port;
- char *localaddr;
- int localport;
+ union {
+ struct {
+ char *address;
+ int port;
+ char *localaddr;
+ int localport;
+ } net;
+ char *path;
} socket; /* any of NET_CLIENT or NET_SERVER or NET_MCAST */
struct {
char *name;
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 5717f7b98d..c1687e582e 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3639,37 +3639,55 @@ qemuBuildHostNetStr(virDomainNetDefPtr net,
break;
case VIR_DOMAIN_NET_TYPE_CLIENT:
- if (virJSONValueObjectCreate(&netprops, "s:type", "socket", NULL) < 0 ||
- virJSONValueObjectAppendStringPrintf(netprops, "connect", "%s:%d",
- net->data.socket.address,
- net->data.socket.port) < 0)
+ if (virJSONValueObjectCreate(&netprops, "s:type", "socket", NULL) < 0)
+ return NULL;
+
+ if (net->data.socket.path != NULL) {
+ if (virJSONValueObjectAppendStringPrintf(netprops, "connect", "%s",
+ net->data.socket.path) < 0)
+ return NULL;
+ break;
+ }
+
+ if (virJSONValueObjectAppendStringPrintf(netprops, "connect", "%s:%d",
+ net->data.socket.net.address,
+ net->data.socket.net.port) < 0)
return NULL;
break;
case VIR_DOMAIN_NET_TYPE_SERVER:
- if (virJSONValueObjectCreate(&netprops, "s:type", "socket", NULL) < 0 ||
- virJSONValueObjectAppendStringPrintf(netprops, "listen", "%s:%d",
- NULLSTR_EMPTY(net->data.socket.address),
- net->data.socket.port) < 0)
+ if (virJSONValueObjectCreate(&netprops, "s:type", "socket", NULL) < 0)
+ return NULL;
+
+ if (net->data.socket.path != NULL) {
+ if (virJSONValueObjectAppendStringPrintf(netprops, "listen", "%s",
+ net->data.socket.path) < 0)
+ return NULL;
+ break;
+ }
+
+ if (virJSONValueObjectAppendStringPrintf(netprops, "listen", "%s:%d",
+ NULLSTR_EMPTY(net->data.socket.net.address),
+ net->data.socket.net.port) < 0)
return NULL;
break;
case VIR_DOMAIN_NET_TYPE_MCAST:
if (virJSONValueObjectCreate(&netprops, "s:type", "socket", NULL) < 0 ||
virJSONValueObjectAppendStringPrintf(netprops, "mcast", "%s:%d",
- net->data.socket.address,
- net->data.socket.port) < 0)
+ net->data.socket.net.address,
+ net->data.socket.net.port) < 0)
return NULL;
break;
case VIR_DOMAIN_NET_TYPE_UDP:
if (virJSONValueObjectCreate(&netprops, "s:type", "socket", NULL) < 0 ||
virJSONValueObjectAppendStringPrintf(netprops, "udp", "%s:%d",
- net->data.socket.address,
- net->data.socket.port) < 0 ||
+ net->data.socket.net.address,
+ net->data.socket.net.port) < 0 ||
virJSONValueObjectAppendStringPrintf(netprops, "localaddr", "%s:%d",
- net->data.socket.localaddr,
- net->data.socket.localport) < 0)
+ net->data.socket.net.localaddr,
+ net->data.socket.net.localport) < 0)
return NULL;
break;
diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
index a66354426d..8ca86f9c53 100644
--- a/src/qemu/qemu_hotplug.c
+++ b/src/qemu/qemu_hotplug.c
@@ -3752,9 +3752,11 @@ qemuDomainChangeNet(virQEMUDriverPtr driver,
case VIR_DOMAIN_NET_TYPE_CLIENT:
case VIR_DOMAIN_NET_TYPE_MCAST:
case VIR_DOMAIN_NET_TYPE_UDP:
- if (STRNEQ_NULLABLE(olddev->data.socket.address,
- newdev->data.socket.address) ||
- olddev->data.socket.port != newdev->data.socket.port) {
+ if (STRNEQ_NULLABLE(olddev->data.socket.path,
+ newdev->data.socket.path) ||
+ STRNEQ_NULLABLE(olddev->data.socket.net.address,
+ newdev->data.socket.net.address) ||
+ olddev->data.socket.net.port != newdev->data.socket.net.port) {
needReconnect = true;
}
break;
--
2.28.0

2
passt.c
View File

@ -591,7 +591,7 @@ listen:
info("or directly qemu, patched with:");
info(" qemu/0001-net-Allow-also-UNIX-domain-sockets-to-be-used-as-net.patch");
info("as follows:");
info("kvm ... -net socket,connect="
info(" kvm ... -net socket,connect="
UNIX_SOCK_PATH " -net nic,model=virtio");
c.fd_unix = accept(fd_unix, NULL, NULL);