[PATCH v2] qemu: tpm: Run swtpm_setup --create-config-files in session mode
Using swtpm v0.7.0 we can run swtpm_setup to create default config files for swtpm_setup and swtpm-localca in session mode. Now a user can start a VM with an attached TPM without having to run this program on the command line before. This program needs to run once. This patch addresses the issue raised in https://bugzilla.redhat.com/show_bug.cgi?id=2010649 Signed-off-by: Stefan Berger <stefanb@linux.ibm.com> v2: - fixed return code if swtpm_setup doesn't support the option --- src/qemu/qemu_tpm.c | 43 +++++++++++++++++++++++++++++++++++++++++++ src/util/virtpm.c | 1 + src/util/virtpm.h | 1 + 3 files changed, 45 insertions(+) diff --git a/src/qemu/qemu_tpm.c b/src/qemu/qemu_tpm.c index 100481503c..bf6c8e5ad5 100644 --- a/src/qemu/qemu_tpm.c +++ b/src/qemu/qemu_tpm.c @@ -385,6 +385,46 @@ qemuTPMSetupEncryption(const unsigned char *secretuuid, return virCommandSetSendBuffer(cmd, g_steal_pointer(&secret), secret_len); } + +/* + * qemuTPMCreateConfigFiles: run swtpm_setup --create-config-files skip-if-exist + * + * @logfile: The file to write the log into; it must be writable + * for the user given by userid or 'tss' + */ +static int +qemuTPMCreateConfigFiles(const char *logfile) +{ + g_autofree char *swtpm_setup = virTPMGetSwtpmSetup(); + g_autoptr(virCommand) cmd = NULL; + int exitstatus; + + if (!swtpm_setup) + return -1; + + if (!virTPMSwtpmSetupCapsGet( + VIR_TPM_SWTPM_SETUP_FEATURE_CMDARG_CREATE_CONFIG_FILES)) + return 0; + + cmd = virCommandNew(swtpm_setup); + if (!cmd) + return -1; + + virCommandAddArgList(cmd, "--create-config-files", "skip-if-exist", NULL); + virCommandClearCaps(cmd); + + if (virCommandRun(cmd, &exitstatus) < 0 || exitstatus != 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("Could not run '%s' to create config files. exitstatus: %d; " + "Check error log '%s' for details."), + swtpm_setup, exitstatus, logfile); + return -1; + } + + return 0; +} + + /* * qemuTPMEmulatorRunSetup * @@ -432,6 +472,9 @@ qemuTPMEmulatorRunSetup(const char *storagepath, "this requires privileged mode for a " "TPM 1.2\n"), 0600); + if (!privileged && qemuTPMCreateConfigFiles(logfile)) + return -1; + cmd = virCommandNew(swtpm_setup); if (!cmd) return -1; diff --git a/src/util/virtpm.c b/src/util/virtpm.c index 1a567139b4..0f50de866c 100644 --- a/src/util/virtpm.c +++ b/src/util/virtpm.c @@ -45,6 +45,7 @@ VIR_ENUM_IMPL(virTPMSwtpmFeature, VIR_ENUM_IMPL(virTPMSwtpmSetupFeature, VIR_TPM_SWTPM_SETUP_FEATURE_LAST, "cmdarg-pwdfile-fd", + "cmdarg-create-config-files", ); /** diff --git a/src/util/virtpm.h b/src/util/virtpm.h index d021a083b4..3bb03b3b33 100644 --- a/src/util/virtpm.h +++ b/src/util/virtpm.h @@ -38,6 +38,7 @@ typedef enum { typedef enum { VIR_TPM_SWTPM_SETUP_FEATURE_CMDARG_PWDFILE_FD, + VIR_TPM_SWTPM_SETUP_FEATURE_CMDARG_CREATE_CONFIG_FILES, VIR_TPM_SWTPM_SETUP_FEATURE_LAST } virTPMSwtpmSetupFeature; -- 2.31.1
On Fri, Oct 8, 2021 at 5:56 PM Stefan Berger <stefanb@linux.ibm.com> wrote:
Using swtpm v0.7.0 we can run swtpm_setup to create default config files for swtpm_setup and swtpm-localca in session mode. Now a user can start a VM with an attached TPM without having to run this program on the command line before. This program needs to run once.
This patch addresses the issue raised in https://bugzilla.redhat.com/show_bug.cgi?id=2010649
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
v2: - fixed return code if swtpm_setup doesn't support the option --- src/qemu/qemu_tpm.c | 43 +++++++++++++++++++++++++++++++++++++++++++ src/util/virtpm.c | 1 + src/util/virtpm.h | 1 + 3 files changed, 45 insertions(+)
diff --git a/src/qemu/qemu_tpm.c b/src/qemu/qemu_tpm.c index 100481503c..bf6c8e5ad5 100644 --- a/src/qemu/qemu_tpm.c +++ b/src/qemu/qemu_tpm.c @@ -385,6 +385,46 @@ qemuTPMSetupEncryption(const unsigned char *secretuuid, return virCommandSetSendBuffer(cmd, g_steal_pointer(&secret), secret_len); }
+ +/* + * qemuTPMCreateConfigFiles: run swtpm_setup --create-config-files skip-if-exist + * + * @logfile: The file to write the log into; it must be writable + * for the user given by userid or 'tss' + */ +static int +qemuTPMCreateConfigFiles(const char *logfile) +{ + g_autofree char *swtpm_setup = virTPMGetSwtpmSetup(); + g_autoptr(virCommand) cmd = NULL; + int exitstatus; + + if (!swtpm_setup) + return -1; + + if (!virTPMSwtpmSetupCapsGet( + VIR_TPM_SWTPM_SETUP_FEATURE_CMDARG_CREATE_CONFIG_FILES)) + return 0; + + cmd = virCommandNew(swtpm_setup); + if (!cmd) + return -1; + + virCommandAddArgList(cmd, "--create-config-files", "skip-if-exist", NULL); + virCommandClearCaps(cmd); + + if (virCommandRun(cmd, &exitstatus) < 0 || exitstatus != 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("Could not run '%s' to create config files. exitstatus: %d; " + "Check error log '%s' for details."), + swtpm_setup, exitstatus, logfile);
logfile isn't used, it seems + return -1;
+ } + + return 0; +} + + /* * qemuTPMEmulatorRunSetup * @@ -432,6 +472,9 @@ qemuTPMEmulatorRunSetup(const char *storagepath, "this requires privileged mode for a " "TPM 1.2\n"), 0600);
+ if (!privileged && qemuTPMCreateConfigFiles(logfile)) + return -1; + cmd = virCommandNew(swtpm_setup); if (!cmd) return -1; diff --git a/src/util/virtpm.c b/src/util/virtpm.c index 1a567139b4..0f50de866c 100644 --- a/src/util/virtpm.c +++ b/src/util/virtpm.c @@ -45,6 +45,7 @@ VIR_ENUM_IMPL(virTPMSwtpmFeature, VIR_ENUM_IMPL(virTPMSwtpmSetupFeature, VIR_TPM_SWTPM_SETUP_FEATURE_LAST, "cmdarg-pwdfile-fd", + "cmdarg-create-config-files", );
/** diff --git a/src/util/virtpm.h b/src/util/virtpm.h index d021a083b4..3bb03b3b33 100644 --- a/src/util/virtpm.h +++ b/src/util/virtpm.h @@ -38,6 +38,7 @@ typedef enum {
typedef enum { VIR_TPM_SWTPM_SETUP_FEATURE_CMDARG_PWDFILE_FD, + VIR_TPM_SWTPM_SETUP_FEATURE_CMDARG_CREATE_CONFIG_FILES,
VIR_TPM_SWTPM_SETUP_FEATURE_LAST } virTPMSwtpmSetupFeature; -- 2.31.1
lgtm otherwise
On Fri, Oct 08, 2021 at 09:56:35AM -0400, Stefan Berger wrote:
Using swtpm v0.7.0 we can run swtpm_setup to create default config files for swtpm_setup and swtpm-localca in session mode. Now a user can start a VM with an attached TPM without having to run this program on the command line before. This program needs to run once.
Fedora 34 only has v0.6.0 and so....
This patch addresses the issue raised in https://bugzilla.redhat.com/show_bug.cgi?id=2010649
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
v2: - fixed return code if swtpm_setup doesn't support the option --- src/qemu/qemu_tpm.c | 43 +++++++++++++++++++++++++++++++++++++++++++ src/util/virtpm.c | 1 + src/util/virtpm.h | 1 + 3 files changed, 45 insertions(+)
diff --git a/src/qemu/qemu_tpm.c b/src/qemu/qemu_tpm.c index 100481503c..bf6c8e5ad5 100644 --- a/src/qemu/qemu_tpm.c +++ b/src/qemu/qemu_tpm.c @@ -385,6 +385,46 @@ qemuTPMSetupEncryption(const unsigned char *secretuuid, return virCommandSetSendBuffer(cmd, g_steal_pointer(&secret), secret_len); }
+ +/* + * qemuTPMCreateConfigFiles: run swtpm_setup --create-config-files skip-if-exist + * + * @logfile: The file to write the log into; it must be writable + * for the user given by userid or 'tss' + */ +static int +qemuTPMCreateConfigFiles(const char *logfile) +{ + g_autofree char *swtpm_setup = virTPMGetSwtpmSetup(); + g_autoptr(virCommand) cmd = NULL; + int exitstatus; + + if (!swtpm_setup) + return -1; + + if (!virTPMSwtpmSetupCapsGet( + VIR_TPM_SWTPM_SETUP_FEATURE_CMDARG_CREATE_CONFIG_FILES)) + return 0; + + cmd = virCommandNew(swtpm_setup); + if (!cmd) + return -1; + + virCommandAddArgList(cmd, "--create-config-files", "skip-if-exist", NULL); + virCommandClearCaps(cmd); + + if (virCommandRun(cmd, &exitstatus) < 0 || exitstatus != 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("Could not run '%s' to create config files. exitstatus: %d; " + "Check error log '%s' for details."), + swtpm_setup, exitstatus, logfile);
This error path will trigger preventing use of the TPM, even if the user has manually setup the config themselves. Why aren't you running /usr/share/swtpm/swtpm-create-user-config-files instead which is what I see does exist on Fedora today. RHEL-8 has even older swtpm than Fedora. Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
On 10/8/21 10:43 AM, Daniel P. Berrangé wrote:
On Fri, Oct 08, 2021 at 09:56:35AM -0400, Stefan Berger wrote:
Using swtpm v0.7.0 we can run swtpm_setup to create default config files for swtpm_setup and swtpm-localca in session mode. Now a user can start a VM with an attached TPM without having to run this program on the command line before. This program needs to run once. Fedora 34 only has v0.6.0 and so....
This is a new feature that will come out with v0.7.0.
This patch addresses the issue raised in https://bugzilla.redhat.com/show_bug.cgi?id=2010649
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
v2: - fixed return code if swtpm_setup doesn't support the option --- src/qemu/qemu_tpm.c | 43 +++++++++++++++++++++++++++++++++++++++++++ src/util/virtpm.c | 1 + src/util/virtpm.h | 1 + 3 files changed, 45 insertions(+)
diff --git a/src/qemu/qemu_tpm.c b/src/qemu/qemu_tpm.c index 100481503c..bf6c8e5ad5 100644 --- a/src/qemu/qemu_tpm.c +++ b/src/qemu/qemu_tpm.c @@ -385,6 +385,46 @@ qemuTPMSetupEncryption(const unsigned char *secretuuid, return virCommandSetSendBuffer(cmd, g_steal_pointer(&secret), secret_len); }
+ +/* + * qemuTPMCreateConfigFiles: run swtpm_setup --create-config-files skip-if-exist + * + * @logfile: The file to write the log into; it must be writable + * for the user given by userid or 'tss' + */ +static int +qemuTPMCreateConfigFiles(const char *logfile) +{ + g_autofree char *swtpm_setup = virTPMGetSwtpmSetup(); + g_autoptr(virCommand) cmd = NULL; + int exitstatus; + + if (!swtpm_setup) + return -1; + + if (!virTPMSwtpmSetupCapsGet( + VIR_TPM_SWTPM_SETUP_FEATURE_CMDARG_CREATE_CONFIG_FILES)) + return 0; + + cmd = virCommandNew(swtpm_setup); + if (!cmd) + return -1; + + virCommandAddArgList(cmd, "--create-config-files", "skip-if-exist", NULL); + virCommandClearCaps(cmd); + + if (virCommandRun(cmd, &exitstatus) < 0 || exitstatus != 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("Could not run '%s' to create config files. exitstatus: %d; " + "Check error log '%s' for details."), + swtpm_setup, exitstatus, logfile); This error path will trigger preventing use of the TPM, even if the user has manually setup the config themselves.
skip-if-exists results in exit code 0 if any one of the 3 expected files exist.
Why aren't you running /usr/share/swtpm/swtpm-create-user-config-files instead which is what I see does exist on Fedora today.
RHEL-8 has even older swtpm than Fedora.
This patch will be backported then and not regarded as new feature?
Regards, Daniel
On Fri, Oct 08, 2021 at 10:51:24AM -0400, Stefan Berger wrote:
On 10/8/21 10:43 AM, Daniel P. Berrangé wrote:
On Fri, Oct 08, 2021 at 09:56:35AM -0400, Stefan Berger wrote:
Using swtpm v0.7.0 we can run swtpm_setup to create default config files for swtpm_setup and swtpm-localca in session mode. Now a user can start a VM with an attached TPM without having to run this program on the command line before. This program needs to run once. Fedora 34 only has v0.6.0 and so....
This is a new feature that will come out with v0.7.0.
This patch addresses the issue raised in https://bugzilla.redhat.com/show_bug.cgi?id=2010649
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
v2: - fixed return code if swtpm_setup doesn't support the option --- src/qemu/qemu_tpm.c | 43 +++++++++++++++++++++++++++++++++++++++++++ src/util/virtpm.c | 1 + src/util/virtpm.h | 1 + 3 files changed, 45 insertions(+)
diff --git a/src/qemu/qemu_tpm.c b/src/qemu/qemu_tpm.c index 100481503c..bf6c8e5ad5 100644 --- a/src/qemu/qemu_tpm.c +++ b/src/qemu/qemu_tpm.c @@ -385,6 +385,46 @@ qemuTPMSetupEncryption(const unsigned char *secretuuid, return virCommandSetSendBuffer(cmd, g_steal_pointer(&secret), secret_len); } + +/* + * qemuTPMCreateConfigFiles: run swtpm_setup --create-config-files skip-if-exist + * + * @logfile: The file to write the log into; it must be writable + * for the user given by userid or 'tss' + */ +static int +qemuTPMCreateConfigFiles(const char *logfile) +{ + g_autofree char *swtpm_setup = virTPMGetSwtpmSetup(); + g_autoptr(virCommand) cmd = NULL; + int exitstatus; + + if (!swtpm_setup) + return -1; + + if (!virTPMSwtpmSetupCapsGet( + VIR_TPM_SWTPM_SETUP_FEATURE_CMDARG_CREATE_CONFIG_FILES)) + return 0; + + cmd = virCommandNew(swtpm_setup); + if (!cmd) + return -1; + + virCommandAddArgList(cmd, "--create-config-files", "skip-if-exist", NULL); + virCommandClearCaps(cmd); + + if (virCommandRun(cmd, &exitstatus) < 0 || exitstatus != 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("Could not run '%s' to create config files. exitstatus: %d; " + "Check error log '%s' for details."), + swtpm_setup, exitstatus, logfile); This error path will trigger preventing use of the TPM, even if the user has manually setup the config themselves.
skip-if-exists results in exit code 0 if any one of the 3 expected files exist.
No, you mis-understand me. I have creates the cofnig by running /usr/share/swtpm/swtpm-create-user-config-files. Now this libvirt tries to invoke swtpm_setup --create-config-files skip-if-exists which fails to parse the command line, as I don't have version 0.7.0, and thus prevents my VMs working
Why aren't you running /usr/share/swtpm/swtpm-create-user-config-files instead which is what I see does exist on Fedora today.
RHEL-8 has even older swtpm than Fedora.
This patch will be backported then and not regarded as new feature?
We can't assume distros will backport new cli options like that. We need to be able to work correctly with the version of swtpm that is shipped in the various distros today. Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
On 10/8/21 10:43 AM, Daniel P. Berrangé wrote:
This error path will trigger preventing use of the TPM, even if the user has manually setup the config themselves.
Why aren't you running /usr/share/swtpm/swtpm-create-user-config-files instead which is what I see does exist on Fedora today.
That one will exit with error code '1' if any one file exists: # /usr/share/swtpm/swtpm-create-user-config-files File /home/stefanb/.config/swtpm_setup.conf already exists. Refusing to overwrite. # echo $? 1 It wasn't designed to be run by libvirt but by the user on the command line. Stefan
RHEL-8 has even older swtpm than Fedora.
Regards, Daniel
On Fri, Oct 08, 2021 at 09:56:35AM -0400, Stefan Berger wrote:
Using swtpm v0.7.0 we can run swtpm_setup to create default config files for swtpm_setup and swtpm-localca in session mode. Now a user can start a VM with an attached TPM without having to run this program on the command line before. This program needs to run once.
This patch addresses the issue raised in https://bugzilla.redhat.com/show_bug.cgi?id=2010649
BTW, I notice the this tool creates certs under $HOME/.config/var with an expiry date of +10 years. Now that sounds like a long time, and indeed it is a long time, but then I look at the support lifetime of RHEL... Hopefully bare metal hardware won't last for the whole 10 years without being replaced, but with nested virt the "hosts" could be VMs that get moved to new hardware. So what's the story if a host hits the 10 year mark for the swtpm certs ? Presumably swtpm is validating these dates and will refuse to launch the TPM for the VMs on the host ? Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
On 10/8/21 10:52 AM, Daniel P. Berrangé wrote:
On Fri, Oct 08, 2021 at 09:56:35AM -0400, Stefan Berger wrote:
Using swtpm v0.7.0 we can run swtpm_setup to create default config files for swtpm_setup and swtpm-localca in session mode. Now a user can start a VM with an attached TPM without having to run this program on the command line before. This program needs to run once.
This patch addresses the issue raised in https://bugzilla.redhat.com/show_bug.cgi?id=2010649 BTW, I notice the this tool creates certs under $HOME/.config/var with an expiry date of +10 years.
Now that sounds like a long time, and indeed it is a long time, but then I look at the support lifetime of RHEL... Hopefully bare metal hardware won't last for the whole 10 years without being replaced, but with nested virt the "hosts" could be VMs that get moved to new hardware.
So what's the story if a host hits the 10 year mark for the swtpm certs ? Presumably swtpm is validating these dates and will refuse to launch the TPM for the VMs on the host ? It doesn't.
Regards, Daniel
On 10/8/21 10:56 AM, Stefan Berger wrote:
On 10/8/21 10:52 AM, Daniel P. Berrangé wrote:
On Fri, Oct 08, 2021 at 09:56:35AM -0400, Stefan Berger wrote:
Using swtpm v0.7.0 we can run swtpm_setup to create default config files for swtpm_setup and swtpm-localca in session mode. Now a user can start a VM with an attached TPM without having to run this program on the command line before. This program needs to run once.
This patch addresses the issue raised in https://bugzilla.redhat.com/show_bug.cgi?id=2010649 BTW, I notice the this tool creates certs under $HOME/.config/var with an expiry date of +10 years.
Now that sounds like a long time, and indeed it is a long time, but then I look at the support lifetime of RHEL... Hopefully bare metal hardware won't last for the whole 10 years without being replaced, but with nested virt the "hosts" could be VMs that get moved to new hardware.
So what's the story if a host hits the 10 year mark for the swtpm certs ? Presumably swtpm is validating these dates and will refuse to launch the TPM for the VMs on the host ? It doesn't.
I am switching to non-expiring certificates now which should help address this issue for future CAs. These CAs 'created on the fly' were thought of merely as a convenience for the user and someone more serious about the TPM CAs would create them on their own and use appropriate dates for the expiration and manage these certificates before they expire. In a larger setting all hosts should share a fairly well-known TPM CA so that all vTPMs' certificates are signed with the same CA and certificate validators don't need to have n hosts' certs but just '1'. However, that requires setup by an admin rather than relying on CAs 'created on the fly'. Thanks for the feedback Stefan
Regards, Daniel
participants (3)
-
Daniel P. Berrangé -
Marc-André Lureau -
Stefan Berger