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

daemons/Makefile.am

@@ -16,6 +16,7 @@ SUBDIRS =			\
 	ipa-kdb			\
 	ipa-slapi-plugins	\
 	ipa-sam			\
+	ipa-otpd		\
 	$(NULL)
 
 DISTCLEANFILES =		\

daemons/configure.ac

@@ -79,63 +79,17 @@ dnl ---------------------------------------------------------------------------
 dnl - Check for KRB5
 dnl ---------------------------------------------------------------------------
 
-KRB5_LIBS=
 AC_CHECK_HEADER(krb5.h, [], [AC_MSG_ERROR([krb5.h not found])])
-
+AC_CHECK_HEADER(krad.h, [], [AC_MSG_ERROR([krad.h not found])])
-krb5_impl=mit
+AC_CHECK_LIB(krb5, main, [], [AC_MSG_ERROR([libkrb5 not found])])
-
+AC_CHECK_LIB(k5crypto, main, [krb5crypto=k5crypto], [krb5crypto=crypto])
-if test "x$ac_cv_header_krb5_h" = "xyes" ; then
+AC_CHECK_LIB(krad, main, [], [AC_MSG_ERROR([libkrad not found])])
-  dnl lazy check for Heimdal Kerberos
+KRB5_LIBS="-lkrb5 -l$krb5crypto -lcom_err"
-  AC_CHECK_HEADERS(heim_err.h)
+KRAD_LIBS="-lkrad"
-  if test $ac_cv_header_heim_err_h = yes ; then
+krb5kdcdir="${localstatedir}/kerberos/krb5kdc"
-    krb5_impl=heimdal
-  else
-    krb5_impl=mit
-  fi
-
-  if test "x$krb5_impl" = "xmit"; then
-    AC_CHECK_LIB(k5crypto, main,
-      [krb5crypto=k5crypto],
-      [krb5crypto=crypto])
-
-    AC_CHECK_LIB(krb5, main,
-      [have_krb5=yes
-	KRB5_LIBS="-lkrb5 -l$krb5crypto -lcom_err"],
-      [have_krb5=no],
-      [-l$krb5crypto -lcom_err])
-
-  elif test "x$krb5_impl" = "xheimdal"; then
-    AC_CHECK_LIB(des, main,
-      [krb5crypto=des],
-      [krb5crypto=crypto])
-
-    AC_CHECK_LIB(krb5, main,
-      [have_krb5=yes
-	KRB5_LIBS="-lkrb5 -l$krb5crypto -lasn1 -lroken -lcom_err"],
-      [have_krb5=no],
-      [-l$krb5crypto -lasn1 -lroken -lcom_err])
-
-    AC_DEFINE(HAVE_HEIMDAL_KERBEROS, 1,
-      [define if you have HEIMDAL Kerberos])
-
-  else
-    have_krb5=no
-    AC_MSG_WARN([Unrecognized Kerberos5 Implementation])
-  fi
-
-  if test "x$have_krb5" = "xyes" ; then
-    ol_link_krb5=yes
-
-    AC_DEFINE(HAVE_KRB5, 1,
-      [define if you have Kerberos V])
-
-  else
-    AC_MSG_ERROR([Required Kerberos 5 support not available])
-  fi
-
-fi
-
 AC_SUBST(KRB5_LIBS)
+AC_SUBST(KRAD_LIBS)
+AC_SUBST(krb5kdcdir)
 
 dnl ---------------------------------------------------------------------------
 dnl - Check for Mozilla LDAP and OpenLDAP SDK
@@ -262,6 +216,11 @@ AC_CHECK_LIB([pdb],[pdb_enum_upn_suffixes],
              [AC_MSG_WARN([libpdb does not have pdb_enum_upn_suffixes, no support for realm domains in ipasam])],
              [$SAMBA40EXTRA_LIBPATH])
 
+dnl ---------------------------------------------------------------------------
+dnl Check for libverto
+dnl ---------------------------------------------------------------------------
+PKG_CHECK_MODULES([LIBVERTO], [libverto])
+
 dnl ---------------------------------------------------------------------------
 dnl - Check for check unit test framework http://check.sourceforge.net/
 dnl ---------------------------------------------------------------------------
@@ -309,6 +268,20 @@ PKG_CHECK_MODULES([DIRSRV], [dirsrv  >= 1.3.0])
 dnl -- sss_idmap is needed by the extdom exop --
 PKG_CHECK_MODULES([SSSIDMAP], [sss_idmap])
 
+dnl ---------------------------------------------------------------------------
+dnl - Check for systemd unit directory
+dnl ---------------------------------------------------------------------------
+PKG_CHECK_EXISTS([systemd], [], [AC_MSG_ERROR([systemd not found])])
+AC_ARG_WITH([systemdsystemunitdir],
+            AS_HELP_STRING([--with-systemdsystemunitdir=DIR], [Directory for systemd service files]),
+            [], [with_systemdsystemunitdir=$($PKG_CONFIG --variable=systemdsystemunitdir systemd)])
+AC_SUBST([systemdsystemunitdir], [$with_systemdsystemunitdir])
+
+dnl ---------------------------------------------------------------------------
+dnl - Check for program paths
+dnl ---------------------------------------------------------------------------
+AC_PATH_PROG(UNLINK, unlink, [AC_MSG_ERROR([unlink not found])])
+
 dnl ---------------------------------------------------------------------------
 dnl - Set the data install directory since we don't use pkgdatadir
 dnl ---------------------------------------------------------------------------
@@ -373,6 +346,7 @@ AC_CONFIG_FILES([
     Makefile
     ipa-kdb/Makefile
     ipa-sam/Makefile
+    ipa-otpd/Makefile
     ipa-slapi-plugins/Makefile
     ipa-slapi-plugins/ipa-cldap/Makefile
     ipa-slapi-plugins/ipa-dns/Makefile
@@ -394,19 +368,22 @@ echo "
                     IPA Server $VERSION
                     ========================
 
-	prefix:                   ${prefix}
+        prefix:                   ${prefix}
-	exec_prefix:              ${exec_prefix}
+        exec_prefix:              ${exec_prefix}
         libdir:                   ${libdir}
         bindir:                   ${bindir}
         sbindir:                  ${sbindir}
         sysconfdir:               ${sysconfdir}
         localstatedir:            ${localstatedir}
         datadir:                  ${datadir}
-	source code location:	  ${srcdir}
+        krb5kdcdir:               ${krb5kdcdir}
-	compiler:		  ${CC}
+        systemdsystemunitdir:     ${systemdsystemunitdir}
-	cflags:		          ${CFLAGS}
+        source code location:     ${srcdir}
+        compiler:                 ${CC}
+        cflags:                   ${CFLAGS}
         LDAP libs:                ${LDAP_LIBS}
         KRB5 libs:                ${KRB5_LIBS}
+        KRAD libs:                ${KRAD_LIBS}
         OpenSSL libs:             ${SSL_LIBS}
         Maintainer mode:          ${USE_MAINTAINER_MODE}
 "

daemons/ipa-otpd/Makefile.am

@@ -0,0 +1,21 @@
+AM_CFLAGS := $(CFLAGS) @LDAP_CFLAGS@ @LIBVERTO_CFLAGS@
+AM_LDFLAGS := $(LDFLAGS) @LDAP_LIBS@ @LIBVERTO_LIBS@ @KRAD_LIBS@
+
+noinst_HEADERS = internal.h
+libexec_PROGRAMS = ipa-otpd
+dist_noinst_DATA = ipa-otpd.socket.in ipa-otpd@.service.in test.py
+systemdsystemunit_DATA = ipa-otpd.socket ipa-otpd@.service
+
+ipa_otpd_SOURCES = bind.c forward.c main.c parse.c query.c queue.c stdio.c
+
+%.socket: %.socket.in
+	@sed -e 's|@krb5kdcdir[@]|$(krb5kdcdir)|g' \
+	     -e 's|@UNLINK[@]|@UNLINK@|g' \
+	     $< > $@
+
+%.service: %.service.in
+	@sed -e 's|@libexecdir[@]|$(libexecdir)|g' \
+	     -e 's|@sysconfdir[@]|$(sysconfdir)|g' \
+	     $< > $@
+
+CLEANFILES = $(systemdsystemunit_DATA)

daemons/ipa-otpd/bind.c

@@ -0,0 +1,144 @@
+/*
+ * 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 takes requests from query.c and performs an LDAP bind on behalf
+ * of the user. The results are placed in the stdout queue (stdio.c).
+ */
+
+#include "internal.h"
+
+static void on_bind_writable(verto_ctx *vctx, verto_ev *ev)
+{
+    struct otpd_queue *push = &ctx.stdio.responses;
+    const krb5_data *data;
+    struct berval cred;
+    struct otpd_queue_item *item;
+    int i;
+    (void)vctx;
+
+    item = otpd_queue_pop(&ctx.bind.requests);
+    if (item == NULL) {
+        verto_set_flags(ctx.bind.io, VERTO_EV_FLAG_PERSIST |
+                                     VERTO_EV_FLAG_IO_ERROR |
+                                     VERTO_EV_FLAG_IO_READ);
+        return;
+    }
+
+    if (item->user.dn == NULL)
+        goto error;
+
+    data = krad_packet_get_attr(item->req,
+                                krad_attr_name2num("User-Password"), 0);
+    if (data == NULL)
+        goto error;
+
+    cred.bv_val = data->data;
+    cred.bv_len = data->length;
+    i = ldap_sasl_bind(verto_get_private(ev), item->user.dn, LDAP_SASL_SIMPLE,
+                       &cred, NULL, NULL, &item->msgid);
+    if (i != LDAP_SUCCESS) {
+        otpd_log_err(errno, "Unable to initiate bind: %s", ldap_err2string(i));
+        verto_break(ctx.vctx);
+        ctx.exitstatus = 1;
+    }
+
+    otpd_log_req(item->req, "bind start: %s", item->user.dn);
+    push = &ctx.bind.responses;
+
+error:
+    otpd_queue_push(push, item);
+}
+
+static void on_bind_readable(verto_ctx *vctx, verto_ev *ev)
+{
+    const char *errstr = "error";
+    LDAPMessage *results;
+    struct otpd_queue_item *item = NULL;
+    int i, rslt;
+    (void)vctx;
+
+    rslt = ldap_result(verto_get_private(ev), LDAP_RES_ANY, 0, NULL, &results);
+    if (rslt != LDAP_RES_BIND) {
+        if (rslt <= 0)
+            results = NULL;
+        ldap_msgfree(results);
+        return;
+    }
+
+    item = otpd_queue_pop_msgid(&ctx.bind.responses, ldap_msgid(results));
+    if (item == NULL) {
+        ldap_msgfree(results);
+        return;
+    }
+    item->msgid = -1;
+
+    rslt = ldap_parse_result(verto_get_private(ev), results, &i,
+                             NULL, NULL, NULL, NULL, 0);
+    if (rslt != LDAP_SUCCESS) {
+        errstr = ldap_err2string(rslt);
+        goto error;
+    }
+
+    rslt = i;
+    if (rslt != LDAP_SUCCESS) {
+        errstr = ldap_err2string(rslt);
+        goto error;
+    }
+
+    item->sent = 0;
+    i = krad_packet_new_response(ctx.kctx, SECRET,
+                                 krad_code_name2num("Access-Accept"),
+                                 NULL, item->req, &item->rsp);
+    if (i != 0) {
+        errstr = krb5_get_error_message(ctx.kctx, i);
+        goto error;
+    }
+
+error:
+    if (item != NULL)
+        otpd_log_req(item->req, "bind end: %s",
+                item->rsp != NULL ? "success" : errstr);
+
+    ldap_msgfree(results);
+    otpd_queue_push(&ctx.stdio.responses, item);
+    verto_set_flags(ctx.stdio.writer, VERTO_EV_FLAG_PERSIST |
+                                      VERTO_EV_FLAG_IO_ERROR |
+                                      VERTO_EV_FLAG_IO_READ |
+                                      VERTO_EV_FLAG_IO_WRITE);
+}
+
+void otpd_on_bind_io(verto_ctx *vctx, verto_ev *ev)
+{
+    verto_ev_flag flags;
+
+    flags = verto_get_fd_state(ev);
+    if (flags & VERTO_EV_FLAG_IO_WRITE)
+        on_bind_writable(vctx, ev);
+    if (flags & VERTO_EV_FLAG_IO_READ)
+        on_bind_readable(vctx, ev);
+    if (flags & VERTO_EV_FLAG_IO_ERROR) {
+        otpd_log_err(EIO, "IO error received on bind socket");
+        verto_break(ctx.vctx);
+        ctx.exitstatus = 1;
+    }
+}

daemons/ipa-otpd/forward.c

@@ -0,0 +1,124 @@
+/*
+ * 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 proxies the incoming RADIUS request (stdio.c/query.c) to a
+ * third-party RADIUS server if the user is configured for forwarding. The
+ * result is placed in the stdout queue (stdio.c).
+ */
+
+#include "internal.h"
+
+static void forward_cb(krb5_error_code retval, const krad_packet *request,
+                       const krad_packet *response, void *data)
+{
+    krad_code code, acpt;
+    struct otpd_queue_item *item = data;
+    (void)request;
+
+    acpt = krad_code_name2num("Access-Accept");
+    code = krad_packet_get_code(response);
+    if (retval == 0 && code == acpt) {
+        item->sent = 0;
+        retval = krad_packet_new_response(ctx.kctx, SECRET, acpt,
+                                          NULL, item->req, &item->rsp);
+    }
+
+    otpd_log_req(item->req, "forward end: %s",
+            retval == 0
+                ? krad_code_num2name(code)
+                : krb5_get_error_message(ctx.kctx, retval));
+
+    otpd_queue_push(&ctx.stdio.responses, item);
+    verto_set_flags(ctx.stdio.writer, VERTO_EV_FLAG_PERSIST |
+                                      VERTO_EV_FLAG_IO_ERROR |
+                                      VERTO_EV_FLAG_IO_READ |
+                                      VERTO_EV_FLAG_IO_WRITE);
+}
+
+krb5_error_code otpd_forward(struct otpd_queue_item **item)
+{
+    krad_attr usernameid, passwordid;
+    const krb5_data *password;
+    krb5_error_code retval;
+    char *username;
+    krb5_data data;
+
+    /* Find the username. */
+    username = (*item)->user.ipatokenRadiusUserName;
+    if (username == NULL) {
+        username = (*item)->user.other;
+        if (username == NULL)
+            username = (*item)->user.uid;
+    }
+
+    /* Check to see if we are supposed to forward. */
+    if ((*item)->radius.ipatokenRadiusServer == NULL ||
+        (*item)->radius.ipatokenRadiusSecret == NULL ||
+        username == NULL)
+        return 0;
+
+    otpd_log_req((*item)->req, "forward start: %s / %s", username,
+            (*item)->radius.ipatokenRadiusServer);
+
+    usernameid = krad_attr_name2num("User-Name");
+    passwordid = krad_attr_name2num("User-Password");
+
+    /* Set User-Name. */
+    data.data = username;
+    data.length = strlen(data.data);
+    retval = krad_attrset_add(ctx.attrs, usernameid, &data);
+    if (retval != 0)
+        goto error;
+
+    /* Set User-Password. */
+    password = krad_packet_get_attr((*item)->req, passwordid, 0);
+    if (password == NULL) {
+        krad_attrset_del(ctx.attrs, usernameid, 0);
+        goto error;
+    }
+    retval = krad_attrset_add(ctx.attrs, passwordid, password);
+    if (retval != 0) {
+        krad_attrset_del(ctx.attrs, usernameid, 0);
+        goto error;
+    }
+
+    /* Forward the request to the RADIUS server. */
+    retval = krad_client_send(ctx.client,
+                              krad_code_name2num("Access-Request"),
+                              ctx.attrs,
+                              (*item)->radius.ipatokenRadiusServer,
+                              (*item)->radius.ipatokenRadiusSecret,
+                              (*item)->radius.ipatokenRadiusTimeout,
+                              (*item)->radius.ipatokenRadiusRetries,
+                              forward_cb, *item);
+    krad_attrset_del(ctx.attrs, usernameid, 0);
+    krad_attrset_del(ctx.attrs, passwordid, 0);
+    if (retval == 0)
+        *item = NULL;
+
+error:
+    if (retval != 0)
+        otpd_log_req((*item)->req, "forward end: %s",
+                krb5_get_error_message(ctx.kctx, retval));
+    return retval;
+}

daemons/ipa-otpd/internal.h

@@ -0,0 +1,153 @@
+/*
+ * 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/>.
+ */
+
+#ifndef INTERNAL_H_
+#define INTERNAL_H_
+
+#include "krad.h"
+
+#include <ldap.h>
+
+#include <errno.h>
+
+#define SECRET ""
+#define otpd_log_req(req, ...) \
+    otpd_log_req_(__FILE__, __LINE__, (req), __VA_ARGS__)
+#define otpd_log_err(errnum, ...) \
+    otpd_log_err_(__FILE__, __LINE__, (errnum), __VA_ARGS__)
+
+struct otpd_queue_iter;
+
+struct otpd_queue_item {
+    struct otpd_queue_item *next;
+    krad_packet *req;
+    krad_packet *rsp;
+    size_t sent;
+    char *error;
+
+    struct {
+        char *dn;
+        char *uid;
+        char *ipatokenRadiusUserName;
+        char *ipatokenRadiusConfigLink;
+        char *other;
+    } user;
+
+    struct {
+        char *ipatokenUserMapAttribute;
+        char *ipatokenRadiusSecret;
+        char *ipatokenRadiusServer;
+        time_t ipatokenRadiusTimeout;
+        size_t ipatokenRadiusRetries;
+    } radius;
+    int msgid;
+};
+
+struct otpd_queue {
+    struct otpd_queue_item *head;
+    struct otpd_queue_item *tail;
+};
+
+/* This structure contains our global state. The most important part is the
+ * queues. When a request comes in (stdio.c), it is placed into an item object.
+ * This item exists in only one queue at a time as it flows through this
+ * daemon.
+ *
+ * The flow is: stdin => query => (forward (no queue) or bind) => stdout.
+ */
+struct otpd_context {
+    verto_ctx *vctx;
+    krb5_context kctx;
+    krad_client *client;
+    krad_attrset *attrs;
+    int exitstatus;
+
+    struct {
+        verto_ev *reader;
+        verto_ev *writer;
+        struct otpd_queue responses;
+    } stdio;
+
+    struct {
+        char *base;
+        verto_ev *io;
+        struct otpd_queue requests;
+        struct otpd_queue responses;
+    } query;
+
+    struct {
+        verto_ev *io;
+        struct otpd_queue requests;
+        struct otpd_queue responses;
+    } bind;
+};
+
+extern struct otpd_context ctx;
+
+void otpd_log_req_(const char * const file, int line, krad_packet *req,
+                   const char * const tmpl, ...);
+
+void otpd_log_err_(const char * const file, int line, krb5_error_code code,
+                   const char * const tmpl, ...);
+
+krb5_error_code otpd_queue_item_new(krad_packet *req,
+                                    struct otpd_queue_item **item);
+
+void otpd_queue_item_free(struct otpd_queue_item *item);
+
+krb5_error_code otpd_queue_iter_new(const struct otpd_queue * const *queues,
+                                    struct otpd_queue_iter **iter);
+
+const krad_packet *otpd_queue_iter_func(void *data, krb5_boolean cancel);
+
+void otpd_queue_push(struct otpd_queue *q, struct otpd_queue_item *item);
+
+void otpd_queue_push_head(struct otpd_queue *q, struct otpd_queue_item *item);
+
+struct otpd_queue_item *otpd_queue_peek(struct otpd_queue *q);
+
+struct otpd_queue_item *otpd_queue_pop(struct otpd_queue *q);
+
+struct otpd_queue_item *otpd_queue_pop_msgid(struct otpd_queue *q, int msgid);
+
+void otpd_queue_free_items(struct otpd_queue *q);
+
+void otpd_on_stdin_readable(verto_ctx *vctx, verto_ev *ev);
+
+void otpd_on_stdout_writable(verto_ctx *vctx, verto_ev *ev);
+
+void otpd_on_query_io(verto_ctx *vctx, verto_ev *ev);
+
+void otpd_on_bind_io(verto_ctx *vctx, verto_ev *ev);
+
+krb5_error_code otpd_forward(struct otpd_queue_item **i);
+
+const char *otpd_parse_user(LDAP *ldp, LDAPMessage *entry,
+                            struct otpd_queue_item *item);
+
+const char *otpd_parse_radius(LDAP *ldp, LDAPMessage *entry,
+                              struct otpd_queue_item *item);
+
+const char *otpd_parse_radius_username(LDAP *ldp, LDAPMessage *entry,
+                                       struct otpd_queue_item *item);
+
+#endif /* INTERNAL_H_ */

daemons/ipa-otpd/ipa-otpd.socket.in

@@ -0,0 +1,11 @@
+[Unit]
+Description=ipa-otpd socket
+
+[Socket]
+ListenStream=@krb5kdcdir@/DEFAULT.socket
+ExecStopPre=@UNLINK@ @krb5kdcdir@/DEFAULT.socket
+SocketMode=0600
+Accept=true
+
+[Install]
+WantedBy=krb5kdc.service

daemons/ipa-otpd/ipa-otpd@.service.in

@@ -0,0 +1,9 @@
+[Unit]
+Description=ipa-otpd service
+
+[Service]
+EnvironmentFile=@sysconfdir@/ipa/default.conf
+ExecStart=@libexecdir@/ipa-otpd $ldap_uri
+StandardInput=socket
+StandardOutput=socket
+StandardError=syslog

daemons/ipa-otpd/main.c

@@ -0,0 +1,340 @@
+/*
+ * 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 initializes a systemd socket-activated daemon which receives
+ * RADIUS packets on STDIN and either proxies them to a third party RADIUS
+ * server or performs authentication directly by binding to the LDAP server.
+ * The choice between bind or proxy is made by evaluating LDAP configuration
+ * for the given user.
+ */
+
+#include "internal.h"
+
+#include <signal.h>
+#include <stdbool.h>
+
+/* Our global state. */
+struct otpd_context ctx;
+
+/* Implementation function for logging a request's state. See internal.h. */
+void otpd_log_req_(const char * const file, int line, krad_packet *req,
+                   const char * const tmpl, ...)
+{
+    const krb5_data *data;
+    va_list ap;
+
+#ifdef DEBUG
+    if (file != NULL)
+        fprintf(stderr, "%8s:%03d: ", file, line);
+#else
+    (void)file;
+    (void)line;
+#endif
+
+    data = krad_packet_get_attr(req, krad_attr_name2num("User-Name"), 0);
+    if (data == NULL)
+        fprintf(stderr, "<unknown>: ");
+    else
+        fprintf(stderr, "%*s: ", data->length, data->data);
+
+    va_start(ap, tmpl);
+    vfprintf(stderr, tmpl, ap);
+    va_end(ap);
+
+    fprintf(stderr, "\n");
+}
+
+/* Implementation function for logging a generic error. See internal.h. */
+void otpd_log_err_(const char * const file, int line, krb5_error_code code,
+                   const char * const tmpl, ...)
+{
+    const char *msg;
+    va_list ap;
+
+    if (file != NULL)
+        fprintf(stderr, "%10s:%03d: ", file, line);
+
+    if (code != 0) {
+        msg = krb5_get_error_message(ctx.kctx, code);
+        fprintf(stderr, "%s: ", msg);
+        krb5_free_error_message(ctx.kctx, msg);
+    }
+
+    va_start(ap, tmpl);
+    vfprintf(stderr, tmpl, ap);
+    va_end(ap);
+
+    fprintf(stderr, "\n");
+}
+
+static void on_ldap_free(verto_ctx *vctx, verto_ev *ev)
+{
+    (void)vctx; /* Unused */
+    ldap_unbind_ext_s(verto_get_private(ev), NULL, NULL);
+}
+
+static void on_signal(verto_ctx *vctx, verto_ev *ev)
+{
+    (void)ev; /* Unused */
+    fprintf(stderr, "Signaled, exiting...\n");
+    verto_break(vctx);
+}
+
+static char *find_base(LDAP *ldp)
+{
+    LDAPMessage *results = NULL, *entry;
+    struct berval **vals = NULL;
+    struct timeval timeout;
+    int i, len;
+    char *base = NULL, *attrs[] = {
+        "namingContexts",
+        "defaultNamingContext",
+        NULL
+    };
+
+    timeout.tv_sec = -1;
+    i = ldap_search_ext_s(ldp, "", LDAP_SCOPE_BASE, NULL, attrs,
+                          0, NULL, NULL, &timeout, 1, &results);
+    if (i != LDAP_SUCCESS) {
+        otpd_log_err(0, "Unable to search for query base: %s",
+                     ldap_err2string(i));
+        goto egress;
+    }
+
+    entry = ldap_first_entry(ldp, results);
+    if (entry == NULL) {
+        otpd_log_err(0, "No entries found");
+        goto egress;
+    }
+
+    vals = ldap_get_values_len(ldp, entry, "defaultNamingContext");
+    if (vals == NULL) {
+        vals = ldap_get_values_len(ldp, entry, "namingContexts");
+        if (vals == NULL) {
+            otpd_log_err(0, "No namingContexts found");
+            goto egress;
+        }
+    }
+
+    len = ldap_count_values_len(vals);
+    if (len == 1)
+        base = strndup(vals[0]->bv_val, vals[0]->bv_len);
+    else
+        otpd_log_err(0, "Too many namingContexts found");
+
+    /* TODO: search multiple namingContexts to find the base? */
+
+egress:
+    ldap_value_free_len(vals);
+    ldap_msgfree(results);
+    return base;
+}
+
+/* Set up an LDAP connection as a verto event. */
+static krb5_error_code setup_ldap(const char *uri, krb5_boolean bind,
+                                  verto_callback *io, verto_ev **ev,
+                                  char **base)
+{
+    struct timeval timeout;
+    int err, ver, fd;
+    char *basetmp;
+    LDAP *ldp;
+
+    err = ldap_initialize(&ldp, uri);
+    if (err != LDAP_SUCCESS)
+        return errno;
+
+    ver = LDAP_VERSION3;
+    ldap_set_option(ldp, LDAP_OPT_PROTOCOL_VERSION, &ver);
+
+    if (bind) {
+        err = ldap_sasl_bind_s(ldp, NULL, "EXTERNAL", NULL, NULL, NULL, NULL);
+        if (err != LDAP_SUCCESS)
+            return errno;
+    }
+
+    /* Always find the base since this forces open the socket. */
+    basetmp = find_base(ldp);
+    if (basetmp == NULL)
+        return ENOTCONN;
+    if (base != NULL)
+        *base = basetmp;
+    else
+        free(basetmp);
+
+    /* Set default timeout to just return immediately for async requests. */
+    memset(&timeout, 0, sizeof(timeout));
+    err = ldap_set_option(ldp, LDAP_OPT_TIMEOUT, &timeout);
+    if (err != LDAP_OPT_SUCCESS) {
+        ldap_unbind_ext_s(ldp, NULL, NULL);
+        return ENOMEM; /* What error code do I use? */
+    }
+
+    /* Get the file descriptor. */
+    if (ldap_get_option(ldp, LDAP_OPT_DESC, &fd) != LDAP_OPT_SUCCESS) {
+        ldap_unbind_ext_s(ldp, NULL, NULL);
+        return EINVAL;
+    }
+
+    *ev = verto_add_io(ctx.vctx, VERTO_EV_FLAG_PERSIST |
+                                 VERTO_EV_FLAG_IO_ERROR |
+                                 VERTO_EV_FLAG_IO_READ,
+                       io, fd);
+    if (*ev == NULL) {
+        ldap_unbind_ext_s(ldp, NULL, NULL);
+        return ENOMEM; /* What error code do I use? */
+    }
+
+    verto_set_private(*ev, ldp, on_ldap_free);
+    return 0;
+}
+
+int main(int argc, char **argv)
+{
+    char hostname[HOST_NAME_MAX + 1];
+    krb5_error_code retval;
+    krb5_data hndata;
+    verto_ev *sig;
+
+    if (argc != 2) {
+        fprintf(stderr, "Usage: %s <ldap_uri>\n", argv[0]);
+        return 1;
+    } else {
+        fprintf(stderr, "LDAP: %s\n", argv[1]);
+    }
+
+    memset(&ctx, 0, sizeof(ctx));
+    ctx.exitstatus = 1;
+
+    if (gethostname(hostname, sizeof(hostname)) < 0) {
+        otpd_log_err(errno, "Unable to get hostname");
+        goto error;
+    }
+
+    retval = krb5_init_context(&ctx.kctx);
+    if (retval != 0) {
+        otpd_log_err(retval, "Unable to initialize context");
+        goto error;
+    }
+
+    ctx.vctx = verto_new(NULL, VERTO_EV_TYPE_IO | VERTO_EV_TYPE_SIGNAL);
+    if (ctx.vctx == NULL) {
+        otpd_log_err(ENOMEM, "Unable to initialize event loop");
+        goto error;
+    }
+
+    /* Build attrset. */
+    retval = krad_attrset_new(ctx.kctx, &ctx.attrs);
+    if (retval != 0) {
+        otpd_log_err(retval, "Unable to initialize attrset");
+        goto error;
+    }
+
+    /* Set NAS-Identifier. */
+    hndata.data = hostname;
+    hndata.length = strlen(hndata.data);
+    retval = krad_attrset_add(ctx.attrs, krad_attr_name2num("NAS-Identifier"),
+                              &hndata);
+    if (retval != 0) {
+        otpd_log_err(retval, "Unable to set NAS-Identifier");
+        goto error;
+    }
+
+    /* Set Service-Type. */
+    retval = krad_attrset_add_number(ctx.attrs,
+                                     krad_attr_name2num("Service-Type"),
+                                     KRAD_SERVICE_TYPE_AUTHENTICATE_ONLY);
+    if (retval != 0) {
+        otpd_log_err(retval, "Unable to set Service-Type");
+        goto error;
+    }
+
+    /* Radius Client */
+    retval = krad_client_new(ctx.kctx, ctx.vctx, &ctx.client);
+    if (retval != 0) {
+        otpd_log_err(retval, "Unable to initialize radius client");
+        goto error;
+    }
+
+    /* Signals */
+    sig = verto_add_signal(ctx.vctx, VERTO_EV_FLAG_NONE, on_signal, SIGTERM);
+    if (sig == NULL) {
+        otpd_log_err(ENOMEM, "Unable to initialize signal event");
+        goto error;
+    }
+    sig = verto_add_signal(ctx.vctx, VERTO_EV_FLAG_NONE, on_signal, SIGINT);
+    if (sig == NULL) {
+        otpd_log_err(ENOMEM, "Unable to initialize signal event");
+        goto error;
+    }
+
+    /* Standard IO */
+    ctx.stdio.reader = verto_add_io(ctx.vctx, VERTO_EV_FLAG_PERSIST |
+                                              VERTO_EV_FLAG_IO_ERROR |
+                                              VERTO_EV_FLAG_IO_READ,
+                                    otpd_on_stdin_readable, STDIN_FILENO);
+    if (ctx.stdio.reader == NULL) {
+        otpd_log_err(ENOMEM, "Unable to initialize reader event");
+        goto error;
+    }
+    ctx.stdio.writer = verto_add_io(ctx.vctx, VERTO_EV_FLAG_PERSIST |
+                                              VERTO_EV_FLAG_IO_ERROR |
+                                              VERTO_EV_FLAG_IO_READ,
+                                    otpd_on_stdout_writable, STDOUT_FILENO);
+    if (ctx.stdio.writer == NULL) {
+        otpd_log_err(ENOMEM, "Unable to initialize writer event");
+        goto error;
+    }
+
+    /* LDAP (Query) */
+    retval = setup_ldap(argv[1], TRUE, otpd_on_query_io,
+                        &ctx.query.io, &ctx.query.base);
+    if (retval != 0) {
+        otpd_log_err(retval, "Unable to initialize LDAP (Query)");
+        goto error;
+    }
+
+    /* LDAP (Bind) */
+    retval = setup_ldap(argv[1], FALSE, otpd_on_bind_io,
+                        &ctx.bind.io, NULL);
+    if (retval != 0) {
+        otpd_log_err(retval, "Unable to initialize LDAP (Bind)");
+        goto error;
+    }
+
+    ctx.exitstatus = 0;
+    verto_run(ctx.vctx);
+
+error:
+    krad_client_free(ctx.client);
+    otpd_queue_free_items(&ctx.stdio.responses);
+    otpd_queue_free_items(&ctx.query.requests);
+    otpd_queue_free_items(&ctx.query.responses);
+    otpd_queue_free_items(&ctx.bind.requests);
+    otpd_queue_free_items(&ctx.bind.responses);
+    free(ctx.query.base);
+    verto_free(ctx.vctx);
+    krb5_free_context(ctx.kctx);
+    return ctx.exitstatus;
+}
+

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;
+}

daemons/ipa-otpd/query.c

@@ -0,0 +1,253 @@
+/*
+ * 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 receives requests (from stdio.c) and queries the LDAP server for
+ * the user's configuration. When the user's configuration is received, it is
+ * parsed (parse.c). Once the configuration is parsed, the request packet is
+ * either forwarded to a third-party RADIUS server (forward.c) or authenticated
+ * directly via an LDAP bind (bind.c) based on the configuration received.
+ */
+
+#define _GNU_SOURCE 1 /* for asprintf() */
+#include "internal.h"
+#include <ctype.h>
+
+#define DEFAULT_TIMEOUT 15
+#define DEFAULT_RETRIES 3
+
+static char *user[] = {
+    "uid",
+    "ipatokenRadiusUserName",
+    "ipatokenRadiusConfigLink",
+    NULL
+};
+
+static char *radius[] = {
+    "ipatokenRadiusServer",
+    "ipatokenRadiusSecret",
+    "ipatokenRadiusTimeout",
+    "ipatokenRadiusRetries",
+    "ipatokenUserMapAttribute",
+    NULL
+};
+
+/* Send queued LDAP requests to the server. */
+static void on_query_writable(verto_ctx *vctx, verto_ev *ev)
+{
+    struct otpd_queue *push = &ctx.stdio.responses;
+    const krb5_data *princ = NULL;
+    char *filter = NULL, *attrs[2];
+    int i = LDAP_SUCCESS;
+    struct otpd_queue_item *item;
+    (void)vctx;
+
+    item = otpd_queue_pop(&ctx.query.requests);
+    if (item == NULL) {
+        verto_set_flags(ctx.query.io, VERTO_EV_FLAG_PERSIST |
+                                      VERTO_EV_FLAG_IO_ERROR |
+                                      VERTO_EV_FLAG_IO_READ);
+        return;
+    }
+
+    if (item->user.dn == NULL) {
+        princ = krad_packet_get_attr(item->req,
+                                     krad_attr_name2num("User-Name"), 0);
+        if (princ == NULL)
+            goto error;
+
+        otpd_log_req(item->req, "user query start");
+
+        if (asprintf(&filter, "(&(objectClass=Person)(krbPrincipalName=%*s))",
+                     princ->length, princ->data) < 0)
+            goto error;
+
+        i = ldap_search_ext(verto_get_private(ev), ctx.query.base,
+                            LDAP_SCOPE_SUBTREE, filter, user, 0, NULL,
+                            NULL, NULL, 1, &item->msgid);
+        free(filter);
+
+    } else if (item->radius.ipatokenRadiusSecret == NULL) {
+        otpd_log_req(item->req, "radius query start: %s",
+                item->user.ipatokenRadiusConfigLink);
+
+        i = ldap_search_ext(verto_get_private(ev),
+                            item->user.ipatokenRadiusConfigLink,
+                            LDAP_SCOPE_BASE, NULL, radius, 0, NULL,
+                            NULL, NULL, 1, &item->msgid);
+
+    } else if (item->radius.ipatokenUserMapAttribute != NULL) {
+        otpd_log_req(item->req, "username query start: %s",
+                item->radius.ipatokenUserMapAttribute);
+
+        attrs[0] = item->radius.ipatokenUserMapAttribute;
+        attrs[1] = NULL;
+        i = ldap_search_ext(verto_get_private(ev), item->user.dn,
+                            LDAP_SCOPE_BASE, NULL, attrs, 0, NULL,
+                            NULL, NULL, 1, &item->msgid);
+    }
+
+    if (i == LDAP_SUCCESS) {
+        item->sent++;
+        push = &ctx.query.responses;
+    }
+
+error:
+    otpd_queue_push(push, item);
+}
+
+/* Read LDAP responses from the server. */
+static void on_query_readable(verto_ctx *vctx, verto_ev *ev)
+{
+    struct otpd_queue *push = &ctx.stdio.responses;
+    verto_ev *event = ctx.stdio.writer;
+    LDAPMessage *results, *entry;
+    struct otpd_queue_item *item = NULL;
+    const char *err;
+    LDAP *ldp;
+    int i;
+    (void)vctx;
+
+    ldp = verto_get_private(ev);
+
+    i = ldap_result(ldp, LDAP_RES_ANY, 0, NULL, &results);
+    if (i != LDAP_RES_SEARCH_ENTRY && i != LDAP_RES_SEARCH_RESULT) {
+        if (i <= 0)
+            results = NULL;
+        goto egress;
+    }
+
+    item = otpd_queue_pop_msgid(&ctx.query.responses, ldap_msgid(results));
+    if (item == NULL)
+        goto egress;
+
+    if (i == LDAP_RES_SEARCH_ENTRY) {
+        entry = ldap_first_entry(ldp, results);
+        if (entry == NULL)
+            goto egress;
+
+        err = NULL;
+        switch (item->sent) {
+        case 1:
+            err = otpd_parse_user(ldp, entry, item);
+            break;
+        case 2:
+            err = otpd_parse_radius(ldp, entry, item);
+            break;
+        case 3:
+            err = otpd_parse_radius_username(ldp, entry, item);
+            break;
+        default:
+            ldap_msgfree(entry);
+            goto egress;
+        }
+
+        ldap_msgfree(entry);
+
+        if (err != NULL) {
+            if (item->error != NULL)
+                free(item->error);
+            item->error = strdup(err);
+            if (item->error == NULL)
+                goto egress;
+        }
+
+        otpd_queue_push_head(&ctx.query.responses, item);
+        return;
+    }
+
+    item->msgid = -1;
+
+    switch (item->sent) {
+    case 1:
+        otpd_log_req(item->req, "user query end: %s",
+                item->error == NULL ? item->user.dn : item->error);
+        if (item->user.dn == NULL || item->user.uid == NULL)
+            goto egress;
+        break;
+    case 2:
+        otpd_log_req(item->req, "radius query end: %s",
+                item->error == NULL
+                    ? item->radius.ipatokenRadiusServer
+                    : item->error);
+        if (item->radius.ipatokenRadiusServer == NULL ||
+            item->radius.ipatokenRadiusSecret == NULL)
+            goto egress;
+        break;
+    case 3:
+        otpd_log_req(item->req, "username query end: %s",
+                item->error == NULL ? item->user.other : item->error);
+        break;
+    default:
+        goto egress;
+    }
+
+    if (item->error != NULL)
+        goto egress;
+
+    if (item->sent == 1 && item->user.ipatokenRadiusConfigLink != NULL) {
+        push = &ctx.query.requests;
+        event = ctx.query.io;
+        goto egress;
+    } else if (item->sent == 2 &&
+               item->radius.ipatokenUserMapAttribute != NULL &&
+               item->user.ipatokenRadiusUserName == NULL) {
+        push = &ctx.query.requests;
+        event = ctx.query.io;
+        goto egress;
+    }
+
+    /* Forward to RADIUS if necessary. */
+    i = otpd_forward(&item);
+    if (i != 0)
+        goto egress;
+
+    push = &ctx.bind.requests;
+    event = ctx.bind.io;
+
+egress:
+    ldap_msgfree(results);
+    otpd_queue_push(push, item);
+
+    if (item != NULL)
+        verto_set_flags(event, VERTO_EV_FLAG_PERSIST |
+                               VERTO_EV_FLAG_IO_ERROR |
+                               VERTO_EV_FLAG_IO_READ |
+                               VERTO_EV_FLAG_IO_WRITE);
+}
+
+/* Handle the reading/writing of LDAP query requests asynchronously. */
+void otpd_on_query_io(verto_ctx *vctx, verto_ev *ev)
+{
+    verto_ev_flag flags;
+
+    flags = verto_get_fd_state(ev);
+    if (flags & VERTO_EV_FLAG_IO_WRITE)
+        on_query_writable(vctx, ev);
+    if (flags & VERTO_EV_FLAG_IO_READ)
+        on_query_readable(vctx, ev);
+    if (flags & VERTO_EV_FLAG_IO_ERROR) {
+        otpd_log_err(EIO, "IO error received on query socket");
+        verto_break(ctx.vctx);
+        ctx.exitstatus = 1;
+    }
+}

daemons/ipa-otpd/queue.c

@@ -0,0 +1,183 @@
+/*
+ * 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 contains an implementation of a queue of request/response items.
+ */
+
+#include "internal.h"
+
+struct otpd_queue_iter {
+    struct otpd_queue_item *next;
+    unsigned int qindx;
+    const struct otpd_queue * const *queues;
+};
+
+krb5_error_code otpd_queue_item_new(krad_packet *req,
+                                    struct otpd_queue_item **item)
+{
+    *item = calloc(1, sizeof(struct otpd_queue_item));
+    if (*item == NULL)
+        return ENOMEM;
+
+    (*item)->req = req;
+    (*item)->msgid = -1;
+    return 0;
+}
+
+void otpd_queue_item_free(struct otpd_queue_item *item)
+{
+    if (item == NULL)
+        return;
+
+    ldap_memfree(item->user.dn);
+    free(item->user.uid);
+    free(item->user.ipatokenRadiusUserName);
+    free(item->user.ipatokenRadiusConfigLink);
+    free(item->user.other);
+    free(item->radius.ipatokenRadiusServer);
+    free(item->radius.ipatokenRadiusSecret);
+    free(item->radius.ipatokenUserMapAttribute);
+    free(item->error);
+    krad_packet_free(item->req);
+    krad_packet_free(item->rsp);
+    free(item);
+}
+
+krb5_error_code otpd_queue_iter_new(const struct otpd_queue * const *queues,
+                                    struct otpd_queue_iter **iter)
+{
+    *iter = calloc(1, sizeof(struct otpd_queue_iter));
+    if (*iter == NULL)
+        return ENOMEM;
+
+    (*iter)->queues = queues;
+    return 0;
+}
+
+/* This iterator function is used by krad to loop over all outstanding requests
+ * to check for duplicates. Hence, we have to iterate over all the queues to
+ * return all the outstanding requests as a flat list. */
+const krad_packet *otpd_queue_iter_func(void *data, krb5_boolean cancel)
+{
+    struct otpd_queue_iter *iter = data;
+    const struct otpd_queue *q;
+
+    if (cancel) {
+        free(iter);
+        return NULL;
+    }
+
+    if (iter->next != NULL) {
+        struct otpd_queue_item *tmp;
+        tmp = iter->next;
+        iter->next = tmp->next;
+        return tmp->req;
+    }
+
+    q = iter->queues[iter->qindx++];
+    if (q == NULL)
+        return otpd_queue_iter_func(data, TRUE);
+
+    iter->next = q->head;
+    return otpd_queue_iter_func(data, FALSE);
+}
+
+void otpd_queue_push(struct otpd_queue *q, struct otpd_queue_item *item)
+{
+    if (item == NULL)
+        return;
+
+    if (q->tail == NULL)
+        q->head = q->tail = item;
+    else
+        q->tail = q->tail->next = item;
+}
+
+void otpd_queue_push_head(struct otpd_queue *q, struct otpd_queue_item *item)
+{
+    if (item == NULL)
+        return;
+
+    if (q->head == NULL)
+        q->tail = q->head = item;
+    else {
+        item->next = q->head;
+        q->head = item;
+    }
+}
+
+struct otpd_queue_item *otpd_queue_peek(struct otpd_queue *q)
+{
+    return q->head;
+}
+
+struct otpd_queue_item *otpd_queue_pop(struct otpd_queue *q)
+{
+    struct otpd_queue_item *item;
+
+    if (q == NULL)
+        return NULL;
+
+    item = q->head;
+    if (item != NULL)
+        q->head = item->next;
+
+    if (q->head == NULL)
+        q->tail = NULL;
+
+    return item;
+}
+
+/* Remove and return an item from the queue with the given msgid. */
+struct otpd_queue_item *otpd_queue_pop_msgid(struct otpd_queue *q, int msgid)
+{
+    struct otpd_queue_item *item, **prev;
+
+    for (item = q->head, prev = &q->head;
+         item != NULL;
+         item = item->next, prev = &item->next) {
+        if (item->msgid == msgid) {
+            *prev = item->next;
+            if (q->head == NULL)
+                q->tail = NULL;
+            return item;
+        }
+    }
+
+    return NULL;
+}
+
+void otpd_queue_free_items(struct otpd_queue *q)
+{
+    struct otpd_queue_item *item, *next;
+
+    next = q->head;
+    while (next != NULL) {
+        item = next;
+        next = next->next;
+        otpd_queue_item_free(item);
+    }
+
+    q->head = NULL;
+    q->tail = NULL;
+}

daemons/ipa-otpd/stdio.c

@@ -0,0 +1,205 @@
+/*
+ * 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 reads and writes RADIUS packets on STDIN/STDOUT.
+ *
+ * Incoming requests are placed into a "query" queue to look up the user's
+ * configuration from LDAP (query.c).
+ */
+
+#include "internal.h"
+
+static const struct otpd_queue *const queues[] = {
+    &ctx.stdio.responses,
+    &ctx.query.requests,
+    &ctx.query.responses,
+    &ctx.bind.requests,
+    &ctx.bind.responses,
+    NULL
+};
+
+/* Read a RADIUS request from stdin. */
+void otpd_on_stdin_readable(verto_ctx *vctx, verto_ev *ev)
+{
+    static char _buffer[KRAD_PACKET_SIZE_MAX];
+    static krb5_data buffer = { .data = _buffer, .length = 0 };
+    (void)vctx;
+
+    const krad_packet *dup;
+    const krb5_data *data;
+    struct otpd_queue_iter *iter;
+    struct otpd_queue_item *item;
+    krad_packet *req;
+    ssize_t pktlen;
+    int i;
+
+    pktlen = krad_packet_bytes_needed(&buffer);
+    if (pktlen < 0) {
+        otpd_log_err(EBADMSG, "Received a malformed packet");
+        goto shutdown;
+    }
+
+    /* Read the item. */
+    i = read(verto_get_fd(ev), buffer.data + buffer.length, pktlen);
+    if (i < 1) {
+        /* On EOF, shutdown gracefully. */
+        if (i == 0) {
+            fprintf(stderr, "Socket closed, shutting down...\n");
+            verto_break(ctx.vctx);
+            return;
+        }
+
+        if (errno != EAGAIN && errno != EINTR) {
+            otpd_log_err(errno, "Error receiving packet");
+            goto shutdown;
+        }
+
+        return;
+    }
+
+    /* If we have a partial read or just the header, try again. */
+    buffer.length += i;
+    pktlen = krad_packet_bytes_needed(&buffer);
+    if (pktlen > 0)
+        return;
+
+    /* Create the iterator. */
+    i = otpd_queue_iter_new(queues, &iter);
+    if (i != 0) {
+        otpd_log_err(i, "Unable to create iterator");
+        goto shutdown;
+    }
+
+    /* Decode the item. */
+    i = krad_packet_decode_request(ctx.kctx, SECRET, &buffer,
+                                   otpd_queue_iter_func, iter, &dup, &req);
+    buffer.length = 0;
+    if (i == EAGAIN)
+        return;
+    else if (i != 0) {
+        otpd_log_err(i, "Unable to decode item");
+        goto shutdown;
+    }
+
+    /* Drop duplicate requests. */
+    if (dup != NULL) {
+        krad_packet_free(req);
+        return;
+    }
+
+    /* Ensure the packet has the User-Name attribute. */
+    data = krad_packet_get_attr(req, krad_attr_name2num("User-Name"), 0);
+    if (data == NULL) {
+        krad_packet_free(req);
+        return;
+    }
+
+    /* Create the new queue item. */
+    i = otpd_queue_item_new(req, &item);
+    if (i != 0) {
+        krad_packet_free(req);
+        return;
+    }
+
+    /* Push it to the query queue. */
+    otpd_queue_push(&ctx.query.requests, item);
+    verto_set_flags(ctx.query.io, VERTO_EV_FLAG_PERSIST |
+                                  VERTO_EV_FLAG_IO_ERROR |
+                                  VERTO_EV_FLAG_IO_READ |
+                                  VERTO_EV_FLAG_IO_WRITE);
+
+    otpd_log_req(req, "request received");
+    return;
+
+shutdown:
+    verto_break(ctx.vctx);
+    ctx.exitstatus = 1;
+}
+
+/* Send a RADIUS response to stdout. */
+void otpd_on_stdout_writable(verto_ctx *vctx, verto_ev *ev)
+{
+    const krb5_data *data;
+    struct otpd_queue_item *item;
+    int i;
+    (void)vctx;
+
+    item = otpd_queue_peek(&ctx.stdio.responses);
+    if (item == NULL) {
+        verto_set_flags(ctx.stdio.writer, VERTO_EV_FLAG_PERSIST |
+                                          VERTO_EV_FLAG_IO_ERROR |
+                                          VERTO_EV_FLAG_IO_READ);
+        return;
+    }
+
+    /* If no response has been generated thus far, send Access-Reject. */
+    if (item->rsp == NULL) {
+        item->sent = 0;
+        i = krad_packet_new_response(ctx.kctx, SECRET,
+                                     krad_code_name2num("Access-Reject"),
+                                     NULL, item->req, &item->rsp);
+        if (i != 0) {
+            otpd_log_err(errno, "Unable to craft response");
+            goto shutdown;
+        }
+    }
+
+    /* Send the packet. */
+    data = krad_packet_encode(item->rsp);
+    i = write(verto_get_fd(ev), data->data + item->sent,
+              data->length - item->sent);
+    if (i < 0) {
+        switch (errno) {
+#if defined(EWOULDBLOCK) && (!defined(EAGAIN) || EAGAIN - EWOULDBLOCK != 0)
+        case EWOULDBLOCK:
+#endif
+#if defined(EAGAIN)
+        case EAGAIN:
+#endif
+        case ENOBUFS:
+        case EINTR:
+            /* In this case, we just need to try again. */
+            return;
+        default:
+            /* Unrecoverable. */
+            break;
+        }
+
+        otpd_log_err(errno, "Error writing to stdout!");
+        goto shutdown;
+    }
+
+    /* If the packet was completely sent, free the response. */
+    item->sent += i;
+    if (item->sent == data->length) {
+        otpd_log_req(item->req, "response sent: %s",
+                krad_code_num2name(krad_packet_get_code(item->rsp)));
+        otpd_queue_item_free(otpd_queue_pop(&ctx.stdio.responses));
+    }
+
+    return;
+
+shutdown:
+    verto_break(ctx.vctx);
+    ctx.exitstatus = 1;
+}

daemons/ipa-otpd/test.py

@@ -0,0 +1,61 @@
+#!/usr/bin/python
+#
+# 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/>.
+
+import StringIO
+import struct
+import subprocess
+import sys
+
+try:
+    from pyrad import packet
+    from pyrad.dictionary import Dictionary
+except ImportError:
+    sys.stdout.write("pyrad not found!\n")
+    sys.exit(0)
+
+# We could use a dictionary file, but since we need
+# such few attributes, we'll just include them here
+DICTIONARY = """
+ATTRIBUTE	User-Name	1	string
+ATTRIBUTE	User-Password	2	string
+ATTRIBUTE	NAS-Identifier	32	string
+"""
+
+dct = Dictionary(StringIO.StringIO(DICTIONARY))
+
+proc = subprocess.Popen(["./ipa-otpd", sys.argv[1]],
+                        stdin=subprocess.PIPE, stdout=subprocess.PIPE)
+
+pkt = packet.AuthPacket(secret="", dict=dct)
+pkt["User-Name"] = sys.argv[2]
+pkt["User-Password"] = pkt.PwCrypt(sys.argv[3])
+pkt["NAS-Identifier"] = "localhost"
+proc.stdin.write(pkt.RequestPacket())
+
+rsp = packet.Packet(secret="", dict=dict)
+buf = proc.stdout.read(4)
+buf += proc.stdout.read(struct.unpack("!BBH", buf)[2] - 4)
+rsp.DecodePacket(buf)
+pkt.VerifyReply(rsp)
+
+proc.terminate() #pylint: disable=E1101
+proc.wait()

freeipa.spec.in

@@ -37,11 +37,7 @@ BuildRequires:  nspr-devel
 BuildRequires:  nss-devel
 BuildRequires:  openssl-devel
 BuildRequires:  openldap-devel
-%if 0%{?fedora} >= 19
 BuildRequires:  krb5-devel >= 1.11
-%else
-BuildRequires:  krb5-devel >= 1.10
-%endif
 BuildRequires:  krb5-workstation
 BuildRequires:  libuuid-devel
 BuildRequires:  libcurl-devel >= 7.21.7-2
@@ -73,6 +69,8 @@ BuildRequires:  m2crypto
 BuildRequires:  check
 BuildRequires:  libsss_idmap-devel
 BuildRequires:  java-1.7.0-openjdk
+BuildRequires:  libverto-devel
+BuildRequires:  systemd
 
 # Find out Kerberos middle version to infer ABI changes in DAL driver
 # We cannot load DAL driver into KDC with wrong ABI.
@@ -639,6 +637,7 @@ fi
 %{_sbindir}/ipa-upgradeconfig
 %{_sbindir}/ipa-compliance
 %{_libexecdir}/certmonger/dogtag-ipa-retrieve-agent-submit
+%{_libexecdir}/ipa-otpd
 %{_sysconfdir}/cron.d/ipa-compliance
 %config(noreplace) %{_sysconfdir}/sysconfig/ipa_memcached
 %dir %attr(0700,apache,apache) %{_localstatedir}/run/ipa_memcached/
@@ -647,6 +646,8 @@ fi
 %config %{_sysconfdir}/tmpfiles.d/ipa.conf
 %attr(644,root,root) %{_unitdir}/ipa.service
 %attr(644,root,root) %{_unitdir}/ipa_memcached.service
+%attr(644,root,root) %{_unitdir}/ipa-otpd.socket
+%attr(644,root,root) %{_unitdir}/ipa-otpd@.service
 # END
 %dir %{python_sitelib}/ipaserver
 %dir %{python_sitelib}/ipaserver/install