[libvirt] [PATCH 1/3] Expose ownership ID parsing

[Martin Kletzander]

Parsing 'user:group' is useful even outside the DAC security driver,
so expose the most abstract function which has no DAC security driver
bits in itself.

Signed-off-by: Martin Kletzander <mkletzan at redhat.com>
---
 src/libvirt_private.syms    |  1 +
 src/security/security_dac.c | 51 +++--------------------------------------
 src/util/virutil.c          | 56 +++++++++++++++++++++++++++++++++++++++++++++
 src/util/virutil.h          |  2 ++
 4 files changed, 62 insertions(+), 48 deletions(-)

diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index 9d5f74b..1927451 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -1951,6 +1951,7 @@ virIsCapableVport;
 virIsDevMapperDevice;
 virManageVport;
 virParseNumber;
+virParseOwnershipIds;
 virParseVersionString;
 virPipeReadUntilEOF;
 virReadFCHost;
diff --git a/src/security/security_dac.c b/src/security/security_dac.c
index b8d1a92..0264c28 100644
--- a/src/security/security_dac.c
+++ b/src/security/security_dac.c
@@ -33,6 +33,7 @@
 #include "virscsi.h"
 #include "virstoragefile.h"
 #include "virstring.h"
+#include "virutil.h"

 #define VIR_FROM_THIS VIR_FROM_SECURITY
 #define SECURITY_DAC_NAME "dac"
@@ -70,52 +71,6 @@ virSecurityDACSetDynamicOwnership(virSecurityManagerPtr mgr,
     priv->dynamicOwnership = dynamicOwnership;
 }

-static int
-parseIds(const char *label, uid_t *uidPtr, gid_t *gidPtr)
-{
-    int rc = -1;
-    uid_t theuid;
-    gid_t thegid;
-    char *tmp_label = NULL;
-    char *sep = NULL;
-    char *owner = NULL;
-    char *group = NULL;
-
-    if (VIR_STRDUP(tmp_label, label) < 0)
-        goto cleanup;
-
-    /* Split label */
-    sep = strchr(tmp_label, ':');
-    if (sep == NULL) {
-        virReportError(VIR_ERR_INVALID_ARG,
-                       _("Missing separator ':' in DAC label \"%s\""),
-                       label);
-        goto cleanup;
-    }
-    *sep = '\0';
-    owner = tmp_label;
-    group = sep + 1;
-
-    /* Parse owner and group, error message is defined by
-     * virGetUserID or virGetGroupID.
-     */
-    if (virGetUserID(owner, &theuid) < 0 ||
-        virGetGroupID(group, &thegid) < 0)
-        goto cleanup;
-
-    if (uidPtr)
-        *uidPtr = theuid;
-    if (gidPtr)
-        *gidPtr = thegid;
-
-    rc = 0;
-
-cleanup:
-    VIR_FREE(tmp_label);
-
-    return rc;
-}
-
 /* returns 1 if label isn't found, 0 on success, -1 on error */
 static int
 virSecurityDACParseIds(virDomainDefPtr def, uid_t *uidPtr, gid_t *gidPtr)
@@ -133,7 +88,7 @@ virSecurityDACParseIds(virDomainDefPtr def, uid_t *uidPtr, gid_t *gidPtr)
         return 1;
     }

-    if (parseIds(seclabel->label, &uid, &gid) < 0)
+    if (virParseOwnershipIds(seclabel->label, &uid, &gid) < 0)
         return -1;

     if (uidPtr)
@@ -194,7 +149,7 @@ virSecurityDACParseImageIds(virDomainDefPtr def,
         return 1;
     }

-    if (parseIds(seclabel->imagelabel, &uid, &gid) < 0)
+    if (virParseOwnershipIds(seclabel->imagelabel, &uid, &gid) < 0)
         return -1;

     if (uidPtr)
diff --git a/src/util/virutil.c b/src/util/virutil.c
index 028f1d1..450e5e3 100644
--- a/src/util/virutil.c
+++ b/src/util/virutil.c
@@ -2071,3 +2071,59 @@ virCompareLimitUlong(unsigned long long a, unsigned long b)

     return -1;
 }
+
+/**
+ * virParseOwnershipIds:
+ *
+ * Parse the usual "uid:gid" ownership specification into uid_t and
+ * gid_t passed as parameters.  NULL value for those parameters mean
+ * the information is not needed.  Also, none of those values are
+ * changed in case of any error.
+ *
+ * Returns -1 on error, 0 otherwise.
+ */
+int
+virParseOwnershipIds(const char *label, uid_t *uidPtr, gid_t *gidPtr)
+{
+    int rc = -1;
+    uid_t theuid;
+    gid_t thegid;
+    char *tmp_label = NULL;
+    char *sep = NULL;
+    char *owner = NULL;
+    char *group = NULL;
+
+    if (VIR_STRDUP(tmp_label, label) < 0)
+        goto cleanup;
+
+    /* Split label */
+    sep = strchr(tmp_label, ':');
+    if (sep == NULL) {
+        virReportError(VIR_ERR_INVALID_ARG,
+                       _("Failed to parse uid and gid from '%s'"),
+                       label);
+        goto cleanup;
+    }
+    *sep = '\0';
+    owner = tmp_label;
+    group = sep + 1;
+
+    /* Parse owner and group, error message is defined by
+     * virGetUserID or virGetGroupID.
+     */
+    if (virGetUserID(owner, &theuid) < 0 ||
+        virGetGroupID(group, &thegid) < 0)
+        goto cleanup;
+
+    if (uidPtr)
+        *uidPtr = theuid;
+    if (gidPtr)
+        *gidPtr = thegid;
+
+    rc = 0;
+
+cleanup:
+    VIR_FREE(tmp_label);
+
+    return rc;
+}
diff --git a/src/util/virutil.h b/src/util/virutil.h
index 280a18d..0f6bcc1 100644
--- a/src/util/virutil.h
+++ b/src/util/virutil.h
@@ -166,4 +166,6 @@ char *virFindFCHostCapableVport(const char *sysfs_prefix);

 int virCompareLimitUlong(unsigned long long a, unsigned long b);

+int virParseOwnershipIds(const char *label, uid_t *uidPtr, gid_t *gidPtr);
+
 #endif /* __VIR_UTIL_H__ */
-- 
1.8.2.1