Password change in a transaction, ensure passwords are truly expired

Wrap the password change extop in a transaction.

Fix the case where a password is reset and then immediately used. If done
fast enough then the KDC may not detect that the password is expired and
grant access using the expired password rather than prompting for a reset.

https://fedorahosted.org/freeipa/ticket/1064

1 files changed, 28 insertions, 3 deletions

diff --git a/daemons/ipa-slapi-plugins/ipa-pwd-extop/ipa_pwd_extop.c b/daemons/ipa-slapi-plugins/ipa-pwd-extop/ipa_pwd_extop.c
index 425b1c07..7fcf647f 100644
--- a/daemons/ipa-slapi-plugins/ipa-pwd-extop/ipa_pwd_extop.c
+++ b/daemons/ipa-slapi-plugins/ipa-pwd-extop/ipa_pwd_extop.c
@@ -85,6 +85,7 @@ Slapi_PluginDesc ipapwd_plugin_desc = {
 };
 
 void *ipapwd_plugin_id;
+static int usetxn = 0;
 
 static int filter_keys(struct ipapwd_krbcfg *krbcfg,
                        struct ipapwd_keyset *kset)
@@ -158,6 +159,7 @@ static int ipapwd_chpwop(Slapi_PBlock *pb, struct ipapwd_krbcfg *krbcfg)
 	struct ipapwd_data pwdata;
 	int is_krb, is_smb, is_ipant;
     char *principal = NULL;
+	Slapi_PBlock *chpwop_pb = NULL;
 
 	/* Get the ber value of the extended operation */
 	slapi_pblock_get(pb, SLAPI_EXT_OP_REQ_VALUE, &extop_value);
@@ -238,6 +240,22 @@ static int ipapwd_chpwop(Slapi_PBlock *pb, struct ipapwd_krbcfg *krbcfg)
 	}
 
 parse_req_done:
+
+	if (usetxn) {
+                Slapi_DN *sdn = slapi_sdn_new_dn_byref(dn);
+                Slapi_Backend *be = slapi_be_select(sdn);
+                slapi_sdn_free(&sdn);
+                if (be) {
+			chpwop_pb = slapi_pblock_new();
+			slapi_pblock_set(chpwop_pb, SLAPI_BACKEND, be);
+			rc = slapi_back_transaction_begin(chpwop_pb);
+			if (rc) {
+				LOG_FATAL("failed to start transaction\n");
+			}
+		} else {
+			LOG_FATAL("failed to get be backend from %s\n", dn);
+		}
+	}
 	/* Uncomment for debugging, otherwise we don't want to leak the
 	 * password values into the log... */
 	/* LDAPDebug( LDAP_DEBUG_ARGS, "passwd: dn (%s), oldPasswd (%s),
@@ -499,6 +517,14 @@ parse_req_done:
 
 	/* Free anything that we allocated above */
 free_and_return:
+	if (usetxn && chpwop_pb) {
+		if (rc) { /* fails */
+			slapi_back_transaction_abort(chpwop_pb);
+		} else {
+			slapi_back_transaction_commit(chpwop_pb);
+		}
+		slapi_pblock_destroy(chpwop_pb);
+	}
 	slapi_ch_free_string(&oldPasswd);
 	slapi_ch_free_string(&newPasswd);
 	/* Either this is the same pointer that we allocated and set above,
@@ -1271,12 +1297,11 @@ int ipapwd_init( Slapi_PBlock *pb )
 {
     int ret;
     Slapi_Entry *plugin_entry = NULL;
-    int is_betxn = 0;
 
     /* get args */
     if ((slapi_pblock_get(pb, SLAPI_PLUGIN_CONFIG_ENTRY, &plugin_entry) == 0) &&
         plugin_entry) {
-            is_betxn = slapi_entry_attr_get_bool(plugin_entry,
+            usetxn = slapi_entry_attr_get_bool(plugin_entry,
                                                  "nsslapd-pluginbetxn");
     }
 
@@ -1310,7 +1335,7 @@ int ipapwd_init( Slapi_PBlock *pb )
         return -1;
     }
 
-    if (is_betxn) {
+    if (usetxn) {
         slapi_register_plugin("betxnpreoperation", 1,
                               "ipapwd_pre_init_betxn", ipapwd_pre_init_betxn,
                               "IPA pwd pre ops betxn", NULL,