Add the krb5/FreeIPA RADIUS companion daemon

This daemon listens for RADIUS packets on a well known
UNIX domain socket. When a packet is received, it queries
LDAP to see if the user is configured for RADIUS authentication.
If so, then the packet is forwarded to the 3rd party RADIUS server.
Otherwise, a bind is attempted against the LDAP server.

https://fedorahosted.org/freeipa/ticket/3366
http://freeipa.org/page/V3/OTP

1 files changed, 176 insertions, 0 deletions

diff --git a/daemons/ipa-otpd/parse.c b/daemons/ipa-otpd/parse.c
new file mode 100644
index 000000000..062b64037
--- /dev/null
+++ b/daemons/ipa-otpd/parse.c
@@ -0,0 +1,176 @@
+/*
+ * FreeIPA 2FA companion daemon
+ *
+ * Authors: Nathaniel McCallum <npmccallum@redhat.com>
+ *
+ * Copyright (C) 2013  Nathaniel McCallum, Red Hat
+ * see file 'COPYING' for use and warranty information
+ *
+ * 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/>.
+ */
+
+/*
+ * This file parses the user's configuration received from LDAP (see query.c).
+ */
+
+#include "internal.h"
+#include <ctype.h>
+
+#define DEFAULT_TIMEOUT 15
+#define DEFAULT_RETRIES 3
+
+/* Convert an LDAP entry into an allocated string. */
+static int get_string(LDAP *ldp, LDAPMessage *entry, const char *name,
+                      char **out)
+{
+    struct berval **vals;
+    ber_len_t i;
+    char *buf;
+
+    vals = ldap_get_values_len(ldp, entry, name);
+    if (vals == NULL)
+        return ENOENT;
+
+    buf = calloc(vals[0]->bv_len + 1, sizeof(char));
+    if (buf == NULL) {
+        ldap_value_free_len(vals);
+        return ENOMEM;
+    }
+
+    for (i = 0; i < vals[0]->bv_len; i++) {
+        if (!isprint(vals[0]->bv_val[i])) {
+            free(buf);
+            ldap_value_free_len(vals);
+            return EINVAL;
+        }
+
+        buf[i] = vals[0]->bv_val[i];
+    }
+
+    if (*out != NULL)
+        free(*out);
+    *out = buf;
+    ldap_value_free_len(vals);
+    return 0;
+}
+
+/* Convert an LDAP entry into an unsigned long. */
+static int get_ulong(LDAP *ldp, LDAPMessage *entry, const char *name,
+                     unsigned long *out)
+{
+    struct berval **vals;
+    char buffer[32];
+
+    vals = ldap_get_values_len(ldp, entry, name);
+    if (vals == NULL)
+        return ENOENT;
+
+    if (vals[0]->bv_len > sizeof(buffer) - 1) {
+        ldap_value_free_len(vals);
+        return ERANGE;
+    }
+
+    memcpy(buffer, vals[0]->bv_val, vals[0]->bv_len);
+    buffer[vals[0]->bv_len] = '\0';
+    ldap_value_free_len(vals);
+
+    *out = strtoul(buffer, NULL, 10);
+    if (*out == ULONG_MAX)
+        return errno;
+
+    return 0;
+}
+
+/* Parse basic user configuration. */
+const char *otpd_parse_user(LDAP *ldp, LDAPMessage *entry,
+                            struct otpd_queue_item *item)
+{
+  int i, j;
+
+  i = get_string(ldp, entry, "uid", &item->user.uid);
+  if (i != 0)
+      return strerror(i);
+
+  i = get_string(ldp, entry, "ipatokenRadiusUserName",
+                 &item->user.ipatokenRadiusUserName);
+  if (i != 0 && i != ENOENT)
+      return strerror(i);
+
+  i = get_string(ldp, entry, "ipatokenRadiusConfigLink",
+                 &item->user.ipatokenRadiusConfigLink);
+  if (i != 0 && i != ENOENT)
+      return strerror(i);
+
+  /* Get the DN. */
+  item->user.dn = ldap_get_dn(ldp, entry);
+  if (item->user.dn == NULL) {
+      i = ldap_get_option(ldp, LDAP_OPT_RESULT_CODE, &j);
+      return ldap_err2string(i == LDAP_OPT_SUCCESS ? j : i);
+  }
+
+  return NULL;
+}
+
+/* Parse the user's RADIUS configuration. */
+const char *otpd_parse_radius(LDAP *ldp, LDAPMessage *entry,
+                              struct otpd_queue_item *item)
+{
+  unsigned long l;
+  int i;
+
+  i = get_string(ldp, entry, "ipatokenRadiusServer",
+                 &item->radius.ipatokenRadiusServer);
+  if (i != 0)
+      return strerror(i);
+
+  i = get_string(ldp, entry, "ipatokenRadiusSecret",
+                 &item->radius.ipatokenRadiusSecret);
+  if (i != 0)
+      return strerror(i);
+
+  i = get_string(ldp, entry, "ipatokenUserMapAttribute",
+                 &item->radius.ipatokenUserMapAttribute);
+  if (i != 0 && i != ENOENT)
+      return strerror(i);
+
+  i = get_ulong(ldp, entry, "ipatokenRadiusTimeout", &l);
+  if (i == ENOENT)
+      l = DEFAULT_TIMEOUT;
+  else if (i != 0)
+      return strerror(i);
+  item->radius.ipatokenRadiusTimeout = l * 1000;
+
+  i = get_ulong(ldp, entry, "ipatokenRadiusRetries", &l);
+  if (i == ENOENT)
+      l = DEFAULT_RETRIES;
+  else if (i != 0)
+      return strerror(i);
+  item->radius.ipatokenRadiusRetries = l;
+
+  return NULL;
+}
+
+/* Parse the user's RADIUS username. */
+const char *otpd_parse_radius_username(LDAP *ldp, LDAPMessage *entry,
+                                       struct otpd_queue_item *item)
+{
+  int i;
+
+  i = get_string(ldp, entry, item->radius.ipatokenUserMapAttribute,
+                 &item->user.other);
+  if (i != 0)
+      return strerror(i);
+
+  return NULL;
+}