When support for <interface type='ethernet'> was added in commit
9a4b705f back in 2010, it erroneously looked at <source dev='blah'/>
for a user-specified guest-side interface name. This was never
documented though. (that attribute already existed at the time in the
data.ethernet union member of virDomainNetDef, but apparently had no
practical use - it was only used as a storage place for a NetDef's
bridge name during qemuDomainXMLToNative(), but even then that was
never used for anything).
When support for similar guest-side device naming was added to the lxc
driver several years later, it was put in a new subelement <guest
dev='blah'/>.
In the intervening years, since there was no validation that
ethernet.dev was NULL in the other drivers that didn't actually use
it, innocent souls who were adding other features assuming they needed
to account for non-NULL ethernet.dev when really they didn't, so
little bits of the usual pointless cargo-cult code showed up.
This patch not only switches the openvz driver to use the documented
<guest dev='blah'/> notation for naming the guest-side device (just in
case anyone is still using the openvz driver), and logs an error if
anyone tries to set <source dev='blah'/> for a type='ethernet'
interface, it also removes the cargo-cult uses of ethernet.dev and
<source dev='blah'/>, and eliminates if from the RNG and from
virDomainNetDef.
NB: I decided on this course of action after mentioning the
inconsistency here:
https://www.redhat.com/archives/libvir-list/2016-May/msg02038.html
and getting encouragement do eliminate it in a later IRC discussion
with danpb.
---
docs/schemas/domaincommon.rng | 3 ---
src/conf/domain_conf.c | 32
+++++++++++++++++++---------
src/conf/domain_conf.h | 1 -
src/openvz/openvz_driver.c | 5 ++---
src/qemu/qemu_hotplug.c | 6 +-----
tests/xml2sexprdata/xml2sexpr-net-routed.xml | 1 -
6 files changed, 25 insertions(+), 23 deletions(-)
diff --git a/docs/schemas/domaincommon.rng
b/docs/schemas/domaincommon.rng
index 162c2e0..b81b558 100644
--- a/docs/schemas/domaincommon.rng
+++ b/docs/schemas/domaincommon.rng
@@ -2142,9 +2142,6 @@
<interleave>
<optional>
<element name="source">
- <attribute name="dev">
- <ref name="deviceName"/>
- </attribute>
<empty/>
</element>
</optional>
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 899b6af..4802e03 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -1749,7 +1749,6 @@ virDomainNetDefClear(virDomainNetDefPtr def)
switch (def->type) {
case VIR_DOMAIN_NET_TYPE_ETHERNET:
- VIR_FREE(def->data.ethernet.dev);
break;
case VIR_DOMAIN_NET_TYPE_VHOSTUSER:
@@ -9004,12 +9003,31 @@
virDomainNetDefParseXML(virDomainXMLOptionPtr xmlopt,
def->type == VIR_DOMAIN_NET_TYPE_BRIDGE &&
xmlStrEqual(cur->name, BAD_CAST "source")) {
bridge = virXMLPropString(cur, "bridge");
- } else if (!dev &&
- (def->type == VIR_DOMAIN_NET_TYPE_ETHERNET ||
- def->type == VIR_DOMAIN_NET_TYPE_DIRECT) &&
+ } else if (!dev && def->type ==
VIR_DOMAIN_NET_TYPE_DIRECT &&
xmlStrEqual(cur->name, BAD_CAST "source")) {
dev = virXMLPropString(cur, "dev");
mode = virXMLPropString(cur, "mode");
+ } else if (!dev && def->type ==
VIR_DOMAIN_NET_TYPE_ETHERNET &&
+ xmlStrEqual(cur->name, BAD_CAST "source")) {
+ /* This clause is only necessary because from 2010 to
+ * 2016 it was possible (but never documented) to
+ * configure the name of the guest-side interface of
+ * an openvz domain with <source dev='blah'/>. That
+ * was blatant misuse of <source>, so was likely
+ * (hopefully) never used, but just in case there was
+ * somebody using it, we need to generate an error. If
+ * the openvz driver is ever deprecated, this clause
+ * can be removed from here.
+ */
+ if ((dev = virXMLPropString(cur, "dev"))) {
+ virReportError(VIR_ERR_XML_ERROR,
+ _("Invalid attempt to set
<interface type='ethernet'> "
+ "device name with <source
dev='%s'/>. "
+ "Use <target dev='%s'/> (for
host-side) "
+ "or <guest dev='%s'/> (for
guest-side) instead."),
+ dev, dev, dev);
+ goto error;
+ }
} else if (!vhostuser_path && !vhostuser_mode &&
!vhostuser_type
&& def->type ==
VIR_DOMAIN_NET_TYPE_VHOSTUSER &&
xmlStrEqual(cur->name, BAD_CAST "source")) {
@@ -9260,10 +9278,6 @@ virDomainNetDefParseXML(virDomainXMLOptionPtr
xmlopt,
break;
case VIR_DOMAIN_NET_TYPE_ETHERNET:
- if (dev != NULL) {
- def->data.ethernet.dev = dev;
- dev = NULL;
- }
break;
case VIR_DOMAIN_NET_TYPE_BRIDGE:
@@ -20787,8 +20801,6 @@ virDomainNetDefFormat(virBufferPtr buf,
break;
case VIR_DOMAIN_NET_TYPE_ETHERNET:
- virBufferEscapeString(buf, "<source dev='%s'/>\n",
- def->data.ethernet.dev);
break;
case VIR_DOMAIN_NET_TYPE_VHOSTUSER:
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index b9dc174..e93bd5c 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -931,7 +931,6 @@ struct _virDomainNetDef {
} backend;
union {
struct {
- char *dev;
} ethernet;
