[libvirt] [PATCH] audit: Log only an info message if audit_level < 2 and audit is not supported

[Michal Privoznik]

On 11/27/2017 07:02 PM, Marc Hartmayer wrote:
> Replace the error message during startup of libvirtd with an info
> message if audit_level < 2 and audit is not supported by the
> kernel. Audit is not supported by the current kernel if the kernel
> does not have audit compiled in or if audit is disabled (e.g. by the
> kernel cmdline).
> 
> Signed-off-by: Marc Hartmayer <mhartmay at linux.vnet.ibm.com>
> Reviewed-by: Boris Fiuczynski <fiuczy at linux.vnet.ibm.com>
> ---
>  daemon/libvirtd.c   |  2 +-
>  src/util/viraudit.c | 17 +++++++++++++++--
>  src/util/viraudit.h |  2 +-
>  3 files changed, 17 insertions(+), 4 deletions(-)
> 
> diff --git a/daemon/libvirtd.c b/daemon/libvirtd.c
> index 589b32192e3d..6bbff0d45684 100644
> --- a/daemon/libvirtd.c
> +++ b/daemon/libvirtd.c
> @@ -1418,7 +1418,7 @@ int main(int argc, char **argv) {
>  
>      if (config->audit_level) {
>          VIR_DEBUG("Attempting to configure auditing subsystem");
> -        if (virAuditOpen() < 0) {
> +        if (virAuditOpen(config->audit_level) < 0) {
>              if (config->audit_level > 1) {
>                  ret = VIR_DAEMON_ERR_AUDIT;
>                  goto cleanup;
> diff --git a/src/util/viraudit.c b/src/util/viraudit.c
> index 17e58b3a9574..9b755e384f24 100644
> --- a/src/util/viraudit.c
> +++ b/src/util/viraudit.c
> @@ -55,11 +55,24 @@ static int auditfd = -1;
>  #endif
>  static bool auditlog;
>  
> -int virAuditOpen(void)
> +int virAuditOpen(unsigned int audit_level)

@audit_level might be unused if building without AUDIT enabled.

>  {
>  #if WITH_AUDIT
>      if ((auditfd = audit_open()) < 0) {
> -        virReportSystemError(errno, "%s", _("Unable to initialize audit layer"));
> +        /* You get these error codes only when the kernel does not
> +         * have audit compiled in or it's disabled (e.g. by the kernel
> +         * cmdline) */
> +        if (errno == EINVAL || errno == EPROTONOSUPPORT ||
> +            errno == EAFNOSUPPORT) {
> +            const char msg[] = "Audit is not supported by the kernel";
> +            if (audit_level < 2)
> +                VIR_INFO("%s", _(msg));

This is going to be terrible for translators. If anything, this needs to be:

const char *msg = _("error message");
if ()
  VIR_INFO("%s", msg);
else
  virReportError(msg);

However, I don't think that we need VIR_INFO to have translated messages
at all, therefore we can go with just:

if ()
  VIR_INFO("Audit is not supported");
else
  virReportError(_("Audit is not supported"));

> +            else
> +                virReportError(VIR_FROM_THIS, "%s", _(msg));
> +        } else {
> +            virReportSystemError(errno, "%s", _("Unable to initialize audit layer"));
> +        }
> +

Otherwise looking good. In fact, we document the behaviour you're
implementing. Wonder how we ended up there.

Michal