[PATCH 2/2] conf: Don't generate clashing machine names for embed driver
Michal Privoznik
mprivozn at redhat.com
Fri Mar 13 16:59:47 UTC 2020
So far, when using the qemu:///embed driver, management
applications can't chose whether they want to register their
domains in machined or not. While having that option is certainly
desired, it will require more work. What we can do meanwhile is
to generate names that include part of hash of the root
directory. This is to ensure that if two applications using
different roots but the same domain name (and ID) start the
domain no clashing name for machined is generated.
Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
---
src/conf/domain_conf.c | 18 +++++++++++++++---
src/conf/domain_conf.h | 1 +
src/lxc/lxc_domain.c | 2 +-
src/qemu/qemu_domain.c | 4 +++-
tests/virsystemdtest.c | 35 ++++++++++++++++++++---------------
5 files changed, 40 insertions(+), 20 deletions(-)
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index f8a8d133ba..c4894e1b26 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -62,6 +62,7 @@
#include "virdomainsnapshotobjlist.h"
#include "virdomaincheckpointobjlist.h"
#include "virutil.h"
+#include "vircrypto.h"
#define VIR_FROM_THIS VIR_FROM_DOMAIN
@@ -30956,22 +30957,33 @@ virDomainMachineNameAppendValid(virBufferPtr buf,
char *
virDomainGenerateMachineName(const char *drivername,
+ const char *root,
int id,
const char *name,
bool privileged)
{
- char *username = NULL;
virBuffer buf = VIR_BUFFER_INITIALIZER;
- if (privileged) {
+ if (root) {
+ g_autofree char * hash = NULL;
+
+ /* When two embed drivers start two domains with the same @name and @id
+ * we would generate a non-unique name. Include parts of hashed @root
+ * which guarantees uniqueness. The first 8 characters of SHA256 ought
+ * to be enough for anybody. */
+ if (virCryptoHashString(VIR_CRYPTO_HASH_SHA256, root, &hash) < 0)
+ return NULL;
+
+ virBufferAsprintf(&buf, "%s-embed-%.8s-", drivername, hash);
+ } else if (privileged) {
virBufferAsprintf(&buf, "%s-", drivername);
} else {
+ g_autofree char *username = NULL;
if (!(username = virGetUserName(geteuid()))) {
virBufferFreeAndReset(&buf);
return NULL;
}
virBufferAsprintf(&buf, "%s-%s-", username, drivername);
- VIR_FREE(username);
}
virBufferAsprintf(&buf, "%d-", id);
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index 91b776c28a..73bd097cf8 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -3649,6 +3649,7 @@ int virDomainDiskSetBlockIOTune(virDomainDiskDefPtr disk,
char *
virDomainGenerateMachineName(const char *drivername,
+ const char *root,
int id,
const char *name,
bool privileged);
diff --git a/src/lxc/lxc_domain.c b/src/lxc/lxc_domain.c
index 03d0f46b24..ebd2c2b56e 100644
--- a/src/lxc/lxc_domain.c
+++ b/src/lxc/lxc_domain.c
@@ -406,7 +406,7 @@ virLXCDomainGetMachineName(virDomainDefPtr def, pid_t pid)
}
if (!ret)
- ret = virDomainGenerateMachineName("lxc", def->id, def->name, true);
+ ret = virDomainGenerateMachineName("lxc", NULL, def->id, def->name, true);
return ret;
}
diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index 4b467afa81..dcee42369f 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -16256,6 +16256,7 @@ qemuDomainGetMachineName(virDomainObjPtr vm)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
virQEMUDriverPtr driver = priv->driver;
+ g_autoptr(virQEMUDriverConfig) cfg = virQEMUDriverGetConfig(driver);
char *ret = NULL;
if (vm->pid > 0) {
@@ -16265,7 +16266,8 @@ qemuDomainGetMachineName(virDomainObjPtr vm)
}
if (!ret)
- ret = virDomainGenerateMachineName("qemu", vm->def->id, vm->def->name,
+ ret = virDomainGenerateMachineName("qemu", cfg->root,
+ vm->def->id, vm->def->name,
virQEMUDriverIsPrivileged(driver));
return ret;
diff --git a/tests/virsystemdtest.c b/tests/virsystemdtest.c
index fa0980c845..050941dce8 100644
--- a/tests/virsystemdtest.c
+++ b/tests/virsystemdtest.c
@@ -379,6 +379,7 @@ testGetMachineName(const void *opaque G_GNUC_UNUSED)
struct testNameData {
const char *name;
const char *expected;
+ const char *root;
int id;
bool legacy;
};
@@ -413,8 +414,8 @@ testMachineName(const void *opaque)
int ret = -1;
char *actual = NULL;
- if (!(actual = virDomainGenerateMachineName("qemu", data->id,
- data->name, true)))
+ if (!(actual = virDomainGenerateMachineName("qemu", data->root,
+ data->id, data->name, true)))
goto cleanup;
if (STRNEQ(actual, data->expected)) {
@@ -724,30 +725,34 @@ mymain(void)
TEST_SCOPE_NEW("qemu-3-demo", "machine-qemu\\x2d3\\x2ddemo.scope");
-# define TEST_MACHINE(_name, _id, machinename) \
+# define TEST_MACHINE(_name, _root, _id, machinename) \
do { \
struct testNameData data = { \
- .name = _name, .expected = machinename, .id = _id, \
+ .name = _name, .expected = machinename, .root = _root, .id = _id, \
}; \
if (virTestRun("Test scopename", testMachineName, &data) < 0) \
ret = -1; \
} while (0)
- TEST_MACHINE("demo", 1, "qemu-1-demo");
- TEST_MACHINE("demo-name", 2, "qemu-2-demo-name");
- TEST_MACHINE("demo!name", 3, "qemu-3-demoname");
- TEST_MACHINE(".demo", 4, "qemu-4-demo");
- TEST_MACHINE("bull\U0001f4a9", 5, "qemu-5-bull");
- TEST_MACHINE("demo..name", 6, "qemu-6-demo.name");
- TEST_MACHINE("12345678901234567890123456789012345678901234567890123456789", 7,
+ TEST_MACHINE("demo", NULL, 1, "qemu-1-demo");
+ TEST_MACHINE("demo-name", NULL, 2, "qemu-2-demo-name");
+ TEST_MACHINE("demo!name", NULL, 3, "qemu-3-demoname");
+ TEST_MACHINE(".demo", NULL, 4, "qemu-4-demo");
+ TEST_MACHINE("bull\U0001f4a9", NULL, 5, "qemu-5-bull");
+ TEST_MACHINE("demo..name", NULL, 6, "qemu-6-demo.name");
+ TEST_MACHINE("12345678901234567890123456789012345678901234567890123456789", NULL, 7,
"qemu-7-123456789012345678901234567890123456789012345678901234567");
- TEST_MACHINE("123456789012345678901234567890123456789012345678901234567890", 8,
+ TEST_MACHINE("123456789012345678901234567890123456789012345678901234567890", NULL, 8,
"qemu-8-123456789012345678901234567890123456789012345678901234567");
- TEST_MACHINE("kstest-network-device-default-httpks_(c9eed63e-981e-48ec-acdc-56b3f8c5f678)", 100,
+ TEST_MACHINE("kstest-network-device-default-httpks_(c9eed63e-981e-48ec-acdc-56b3f8c5f678)",
+ NULL, 100,
"qemu-100-kstest-network-device-default-httpksc9eed63e-981e-48ec");
- TEST_MACHINE("kstest-network-device-default-httpks_(c9eed63e-981e-48ec--cdc-56b3f8c5f678)", 10,
+ TEST_MACHINE("kstest-network-device-default-httpks_(c9eed63e-981e-48ec--cdc-56b3f8c5f678)",
+ NULL, 10,
"qemu-10-kstest-network-device-default-httpksc9eed63e-981e-48ec-c");
- TEST_MACHINE("demo.-.test.", 11, "qemu-11-demo.test");
+ TEST_MACHINE("demo.-.test.", NULL, 11, "qemu-11-demo.test");
+ TEST_MACHINE("demo", "/tmp/root1", 1, "qemu-embed-0991f456-1-demo");
+ TEST_MACHINE("demo", "/tmp/root2", 1, "qemu-embed-95d47ff5-1-demo");
# define TESTS_PM_SUPPORT_HELPER(name, function) \
do { \
--
2.24.1
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