[libvirt] [PATCH v4 20/25] security_util: Introduce virSecurityMoveRememberedLabel

[Michal Privoznik]

A simple helper function that would be used from DAC and SELinux
drivers.

Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
Reviewed-by: Cole Robinson <crobinso at redhat.com>
---
 src/security/security_util.c | 63 ++++++++++++++++++++++++++++++++++++
 src/security/security_util.h |  5 +++
 2 files changed, 68 insertions(+)

diff --git a/src/security/security_util.c b/src/security/security_util.c
index 3c24d7cded..ad265b0bc5 100644
--- a/src/security/security_util.c
+++ b/src/security/security_util.c
@@ -256,3 +256,66 @@ virSecuritySetRememberedLabel(const char *name,
     VIR_FREE(ref_name);
     return ret;
 }
+
+
+int
+virSecurityMoveRememberedLabel(const char *name,
+                               const char *src,
+                               const char *dst)
+{
+    VIR_AUTOFREE(char *) ref_name = NULL;
+    VIR_AUTOFREE(char *) ref_value = NULL;
+    VIR_AUTOFREE(char *) attr_name = NULL;
+    VIR_AUTOFREE(char *) attr_value = NULL;
+
+    if (!(ref_name = virSecurityGetRefCountAttrName(name)) |
+        !(attr_name = virSecurityGetAttrName(name)))
+        return -1;
+
+    if (virFileGetXAttrQuiet(src, ref_name, &ref_value) < 0) {
+        if (errno == ENOSYS || errno == ENOTSUP) {
+            return -2;
+        } else if (errno != ENODATA) {
+            virReportSystemError(errno,
+                                 _("Unable to get XATTR %s on %s"),
+                                 ref_name, src);
+            return -1;
+        }
+    }
+
+    if (virFileGetXAttrQuiet(src, attr_name, &attr_value) < 0) {
+        if (errno == ENOSYS || errno == ENOTSUP) {
+            return -2;
+        } else if (errno != ENODATA) {
+            virReportSystemError(errno,
+                                 _("Unable to get XATTR %s on %s"),
+                                 attr_name, src);
+            return -1;
+        }
+    }
+
+    if (ref_value &&
+        virFileRemoveXAttr(src, ref_name) < 0) {
+        return -1;
+    }
+
+    if (attr_value &&
+        virFileRemoveXAttr(src, attr_name) < 0) {
+        return -1;
+    }
+
+    if (dst) {
+        if (ref_value &&
+            virFileSetXAttr(dst, ref_name, ref_value) < 0) {
+            return -1;
+        }
+
+        if (attr_value &&
+            virFileSetXAttr(dst, attr_name, attr_value) < 0) {
+            ignore_value(virFileRemoveXAttr(dst, ref_name));
+            return -1;
+        }
+    }
+
+    return 0;
+}
diff --git a/src/security/security_util.h b/src/security/security_util.h
index bc977ed65d..f727e2e3e5 100644
--- a/src/security/security_util.h
+++ b/src/security/security_util.h
@@ -29,4 +29,9 @@ virSecuritySetRememberedLabel(const char *name,
                               const char *path,
                               const char *label);
 
+int
+virSecurityMoveRememberedLabel(const char *name,
+                               const char *src,
+                               const char *dst);
+
 #endif /* LIBVIRT_SECURITY_UTIL_H */
-- 
2.21.0