[libvirt] [PATCH 2/3] security_dac: Allow selective remember/recall for chardevs

[Michal Privoznik]

While in most cases we want to remember/recall label for a
chardev, there are some special ones (like /dev/tpm0) where we
don't want to remember the seclabel nor recall it. See next
commit for rationale behind.

While the easiest way to implement this would be to just add new
argument to virSecurityDACSetChardevLabel() this one is also a
callback for virSecurityManagerSetChardevLabel() and thus has
more or less stable set of arguments. Therefore, the current
virSecurityDACSetChardevLabel() is renamed to
virSecurityDACSetChardevLabelHelper() and the original function
is set to call the new one.

Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
---
 src/security/security_dac.c | 67 +++++++++++++++++++++++++++----------
 1 file changed, 49 insertions(+), 18 deletions(-)

diff --git a/src/security/security_dac.c b/src/security/security_dac.c
index 5df50bdcf5..2733fa664f 100644
--- a/src/security/security_dac.c
+++ b/src/security/security_dac.c
@@ -1431,10 +1431,11 @@ virSecurityDACRestoreHostdevLabel(virSecurityManagerPtr mgr,
 
 
 static int
-virSecurityDACSetChardevLabel(virSecurityManagerPtr mgr,
-                              virDomainDefPtr def,
-                              virDomainChrSourceDefPtr dev_source,
-                              bool chardevStdioLogd)
+virSecurityDACSetChardevLabelHelper(virSecurityManagerPtr mgr,
+                                    virDomainDefPtr def,
+                                    virDomainChrSourceDefPtr dev_source,
+                                    bool chardevStdioLogd,
+                                    bool remember)
 
 {
     virSecurityDACDataPtr priv = virSecurityManagerGetPrivateData(mgr);
@@ -1471,7 +1472,7 @@ virSecurityDACSetChardevLabel(virSecurityManagerPtr mgr,
     case VIR_DOMAIN_CHR_TYPE_FILE:
         ret = virSecurityDACSetOwnership(mgr, NULL,
                                          dev_source->data.file.path,
-                                         user, group, true);
+                                         user, group, remember);
         break;
 
     case VIR_DOMAIN_CHR_TYPE_PIPE:
@@ -1479,12 +1480,12 @@ virSecurityDACSetChardevLabel(virSecurityManagerPtr mgr,
             virAsprintf(&out, "%s.out", dev_source->data.file.path) < 0)
             goto done;
         if (virFileExists(in) && virFileExists(out)) {
-            if (virSecurityDACSetOwnership(mgr, NULL, in, user, group, true) < 0 ||
-                virSecurityDACSetOwnership(mgr, NULL, out, user, group, true) < 0)
+            if (virSecurityDACSetOwnership(mgr, NULL, in, user, group, remember) < 0 ||
+                virSecurityDACSetOwnership(mgr, NULL, out, user, group, remember) < 0)
                 goto done;
         } else if (virSecurityDACSetOwnership(mgr, NULL,
                                               dev_source->data.file.path,
-                                              user, group, true) < 0) {
+                                              user, group, remember) < 0) {
             goto done;
         }
         ret = 0;
@@ -1499,7 +1500,7 @@ virSecurityDACSetChardevLabel(virSecurityManagerPtr mgr,
              * and passed via FD */
             if (virSecurityDACSetOwnership(mgr, NULL,
                                            dev_source->data.nix.path,
-                                           user, group, true) < 0)
+                                           user, group, remember) < 0)
                 goto done;
         }
         ret = 0;
@@ -1525,11 +1526,24 @@ virSecurityDACSetChardevLabel(virSecurityManagerPtr mgr,
     return ret;
 }
 
+
 static int
-virSecurityDACRestoreChardevLabel(virSecurityManagerPtr mgr,
-                                  virDomainDefPtr def ATTRIBUTE_UNUSED,
-                                  virDomainChrSourceDefPtr dev_source,
-                                  bool chardevStdioLogd)
+virSecurityDACSetChardevLabel(virSecurityManagerPtr mgr,
+                              virDomainDefPtr def,
+                              virDomainChrSourceDefPtr dev_source,
+                              bool chardevStdioLogd)
+{
+    return virSecurityDACSetChardevLabelHelper(mgr, def, dev_source,
+                                               chardevStdioLogd, true);
+}
+
+
+static int
+virSecurityDACRestoreChardevLabelHelper(virSecurityManagerPtr mgr,
+                                        virDomainDefPtr def ATTRIBUTE_UNUSED,
+                                        virDomainChrSourceDefPtr dev_source,
+                                        bool chardevStdioLogd,
+                                        bool recall)
 {
     virSecurityDeviceLabelDefPtr chr_seclabel = NULL;
     char *in = NULL, *out = NULL;
@@ -1549,7 +1563,9 @@ virSecurityDACRestoreChardevLabel(virSecurityManagerPtr mgr,
     switch ((virDomainChrType)dev_source->type) {
     case VIR_DOMAIN_CHR_TYPE_DEV:
     case VIR_DOMAIN_CHR_TYPE_FILE:
-        ret = virSecurityDACRestoreFileLabel(mgr, dev_source->data.file.path);
+        ret = virSecurityDACRestoreFileLabelInternal(mgr, NULL,
+                                                     dev_source->data.file.path,
+                                                     recall);
         break;
 
     case VIR_DOMAIN_CHR_TYPE_PIPE:
@@ -1557,10 +1573,12 @@ virSecurityDACRestoreChardevLabel(virSecurityManagerPtr mgr,
             virAsprintf(&in, "%s.in", dev_source->data.file.path) < 0)
             goto done;
         if (virFileExists(in) && virFileExists(out)) {
-            if (virSecurityDACRestoreFileLabel(mgr, out) < 0 ||
-                virSecurityDACRestoreFileLabel(mgr, in) < 0)
+            if (virSecurityDACRestoreFileLabelInternal(mgr, NULL, out, recall) < 0 ||
+                virSecurityDACRestoreFileLabelInternal(mgr, NULL, in, recall) < 0)
                 goto done;
-        } else if (virSecurityDACRestoreFileLabel(mgr, dev_source->data.file.path) < 0) {
+        } else if (virSecurityDACRestoreFileLabelInternal(mgr, NULL,
+                                                          dev_source->data.file.path,
+                                                          recall) < 0) {
             goto done;
         }
         ret = 0;
@@ -1568,7 +1586,9 @@ virSecurityDACRestoreChardevLabel(virSecurityManagerPtr mgr,
 
     case VIR_DOMAIN_CHR_TYPE_UNIX:
         if (!dev_source->data.nix.listen &&
-            virSecurityDACRestoreFileLabel(mgr, dev_source->data.nix.path) < 0) {
+            virSecurityDACRestoreFileLabelInternal(mgr, NULL,
+                                                   dev_source->data.nix.path,
+                                                   recall) < 0) {
             goto done;
         }
         ret = 0;
@@ -1595,6 +1615,17 @@ virSecurityDACRestoreChardevLabel(virSecurityManagerPtr mgr,
 }
 
 
+static int
+virSecurityDACRestoreChardevLabel(virSecurityManagerPtr mgr,
+                                  virDomainDefPtr def,
+                                  virDomainChrSourceDefPtr dev_source,
+                                  bool chardevStdioLogd)
+{
+    return virSecurityDACRestoreChardevLabelHelper(mgr, def, dev_source,
+                                                   chardevStdioLogd, true);
+}
+
+
 struct _virSecuritySELinuxChardevCallbackData {
     virSecurityManagerPtr mgr;
     bool chardevStdioLogd;
-- 
2.21.0