IPA: Split two functions to new module ipa_subdomains_utils.c

These functions will be later reused by the subdomains_server.c module.
Splitting them into a separate subdomains_utils.c module will make sure
there are no cyclic dependencies and the functions are testable in
isolation.

Reviewed-by: Sumit Bose <sbose@redhat.com>

3 files changed, 111 insertions, 42 deletions

diff --git a/src/providers/ipa/ipa_subdomains.c b/src/providers/ipa/ipa_subdomains.c
index 2a898d7eb..5a3f90fe3 100644
--- a/src/providers/ipa/ipa_subdomains.c
+++ b/src/providers/ipa/ipa_subdomains.c
@@ -328,56 +328,18 @@ static errno_t ipa_subdom_get_forest(TALLOC_CTX *mem_ctx,
                                      char **_forest)
 {
     int ret;
-    const char *orig_dn;
     struct ldb_dn *dn = NULL;
     const struct ldb_val *val;
     char *forest = NULL;
 
-    ret = sysdb_attrs_get_string(attrs, SYSDB_ORIG_DN, &orig_dn);
-    if (ret) {
-        DEBUG(SSSDBG_OP_FAILURE, "sysdb_attrs_get_string failed.\n");
-        goto done;
-    }
-    DEBUG(SSSDBG_TRACE_ALL, "Checking if we need the forest name for [%s].\n",
-                             orig_dn);
-
-    dn = ldb_dn_new(mem_ctx, ldb_ctx, orig_dn);
+    dn = ipa_subdom_ldb_dn(mem_ctx, ldb_ctx, attrs);
     if (dn == NULL) {
-        DEBUG(SSSDBG_OP_FAILURE, "ldb_dn_new failed.\n");
-        goto done;
-    }
-
-    if (!ldb_dn_validate(dn)) {
-        DEBUG(SSSDBG_OP_FAILURE, "Original DN [%s] is not a valid DN.\n",
-                                  orig_dn);
-        ret = EINVAL;
-        goto done;
-    }
-
-    if (ldb_dn_get_comp_num(dn) < 5) {
-        /* We are only interested in the member domain objects. In IPA the
-         * forest root object is stored as e.g.
-         * cn=AD.DOM,cn=ad,cn=trusts,dc=example,dc=com. Member domains in the
-         * forest are children of the forest root object e.g.
-         * cn=SUB.AD.DOM,cn=AD.DOM,cn=ad,cn=trusts,dc=example,dc=com. Since
-         * the forest name is not stored in the member objects we derive it
-         * from the RDN of the forest root object. */
-        ret = EOK;
-        goto done;
-    }
-
-    val = ldb_dn_get_component_val(dn, 3);
-    if (strncasecmp("trusts", (const char *) val->data, val->length) != 0) {
-        DEBUG(SSSDBG_TRACE_FUNC,
-              "4th component is not 'trust', nothing to do.\n");
-        ret = EOK;
+        DEBUG(SSSDBG_OP_FAILURE, "ipa_subdom_ldb_dn failed.\n");
+        ret = EIO;
         goto done;
     }
 
-    val = ldb_dn_get_component_val(dn, 2);
-    if (strncasecmp("ad", (const char *) val->data, val->length) != 0) {
-        DEBUG(SSSDBG_TRACE_FUNC,
-              "3rd component is not 'ad', nothing to do.\n");
+    if (ipa_subdom_is_member_dom(dn) == false) {
         ret = EOK;
         goto done;
     }
@@ -390,6 +352,7 @@ static errno_t ipa_subdom_get_forest(TALLOC_CTX *mem_ctx,
         goto done;
     }
 
+    ret = EOK;
 done:
     talloc_free(dn);
 
diff --git a/src/providers/ipa/ipa_subdomains.h b/src/providers/ipa/ipa_subdomains.h
index d92bd01e8..94027c091 100644
--- a/src/providers/ipa/ipa_subdomains.h
+++ b/src/providers/ipa/ipa_subdomains.h
@@ -59,6 +59,12 @@ void ipa_ad_subdom_remove(struct be_ctx *be_ctx,
 int ipa_ad_subdom_init(struct be_ctx *be_ctx,
                        struct ipa_id_ctx *id_ctx);
 
+struct ldb_dn *ipa_subdom_ldb_dn(TALLOC_CTX *mem_ctx,
+                                 struct ldb_context *ldb_ctx,
+                                 struct sysdb_attrs *attrs);
+
+bool ipa_subdom_is_member_dom(struct ldb_dn *dn);
+
 /* struct for external group memberships, defined in
  * ipa_subdomains_ext_groups.c */
 struct ipa_ext_groups;
diff --git a/src/providers/ipa/ipa_subdomains_utils.c b/src/providers/ipa/ipa_subdomains_utils.c
new file mode 100644
index 000000000..27fc0a4d1
--- /dev/null
+++ b/src/providers/ipa/ipa_subdomains_utils.c
@@ -0,0 +1,100 @@
+/*
+    SSSD
+
+    IPA Subdomains Module - utilities
+
+    Authors:
+        Sumit Bose <sbose@redhat.com>
+
+    Copyright (C) 2015 Red Hat
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "providers/ipa/ipa_subdomains.h"
+#include "providers/ipa/ipa_common.h"
+#include "providers/ipa/ipa_id.h"
+
+struct ldb_dn *ipa_subdom_ldb_dn(TALLOC_CTX *mem_ctx,
+                                 struct ldb_context *ldb_ctx,
+                                 struct sysdb_attrs *attrs)
+{
+    int ret;
+    const char *orig_dn;
+    struct ldb_dn *dn = NULL;
+
+    if (attrs == NULL || ldb_ctx == NULL) {
+        return NULL;
+    }
+
+    ret = sysdb_attrs_get_string(attrs, SYSDB_ORIG_DN, &orig_dn);
+    if (ret) {
+        DEBUG(SSSDBG_OP_FAILURE, "sysdb_attrs_get_string failed: %d\n", ret);
+        return NULL;
+    }
+
+    dn = ldb_dn_new(mem_ctx, ldb_ctx, orig_dn);
+    if (dn == NULL) {
+        DEBUG(SSSDBG_OP_FAILURE, "ldb_dn_new failed.\n");
+        return NULL;
+    }
+
+    if (!ldb_dn_validate(dn)) {
+        DEBUG(SSSDBG_OP_FAILURE, "Original DN [%s] is not a valid DN.\n",
+                                  orig_dn);
+        talloc_free(dn);
+        return NULL;
+    }
+
+    return dn;
+}
+
+bool ipa_subdom_is_member_dom(struct ldb_dn *dn)
+{
+    const struct ldb_val *val;
+
+    if (dn == NULL) {
+        DEBUG(SSSDBG_CRIT_FAILURE, "Wrong input!\n");
+        return false;
+    }
+
+    if (ldb_dn_get_comp_num(dn) < 5) {
+        /* We are only interested in the member domain objects. In IPA the
+         * forest root object is stored as e.g.
+         * cn=AD.DOM,cn=ad,cn=trusts,dc=example,dc=com. Member domains in the
+         * forest are children of the forest root object e.g.
+         * cn=SUB.AD.DOM,cn=AD.DOM,cn=ad,cn=trusts,dc=example,dc=com. Since
+         * the forest name is not stored in the member objects we derive it
+         * from the RDN of the forest root object. */
+        DEBUG(SSSDBG_TRACE_FUNC,
+              "DN too short, not a member domain\n");
+        return false;
+    }
+
+    val = ldb_dn_get_component_val(dn, 3);
+    if (strncasecmp("trusts", (const char *) val->data, val->length) != 0) {
+        DEBUG(SSSDBG_TRACE_FUNC,
+              "4th component is not 'trust', not a member domain\n");
+        return false;
+    }
+
+    val = ldb_dn_get_component_val(dn, 2);
+    if (strncasecmp("ad", (const char *) val->data, val->length) != 0) {
+        DEBUG(SSSDBG_TRACE_FUNC,
+              "3rd component is not 'ad', not a member domain\n");
+        return false;
+    }
+
+    return true;
+}