Make the handling of fd events opaque

Depending on the version of the OpenLDAP libraries we use two different
schemes to find the file descriptor of the connection to the LDAP
server. This patch removes the related ifdefs from the main code and
introduces helper functions which can handle the specific cases.

1 files changed, 259 insertions, 0 deletions

diff --git a/src/providers/ldap/sdap_fd_events.c b/src/providers/ldap/sdap_fd_events.c
new file mode 100644
index 000000000..11527789f
--- /dev/null
+++ b/src/providers/ldap/sdap_fd_events.c
@@ -0,0 +1,259 @@
+/*
+    SSSD
+
+    Helper routines for file descriptor events
+
+    Authors:
+        Sumit Bose <sbose@redhat.com>
+
+    Copyright (C) 2010 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 "util/util.h"
+#include "providers/ldap/sdap_async_private.h"
+
+struct sdap_fd_events {
+#ifdef HAVE_LDAP_CONNCB
+    struct ldap_conncb *conncb;
+#else
+    struct tevent_fd *fde;
+#endif
+};
+
+#ifdef HAVE_LDAP_CONNCB
+static int remove_connection_callback(TALLOC_CTX *mem_ctx)
+{
+    int lret;
+    struct ldap_conncb *conncb = talloc_get_type(mem_ctx, struct ldap_conncb);
+
+    struct ldap_cb_data *cb_data = talloc_get_type(conncb->lc_arg,
+                                                   struct ldap_cb_data);
+
+    lret = ldap_get_option(cb_data->sh->ldap, LDAP_OPT_CONNECT_CB, conncb);
+    if (lret != LDAP_OPT_SUCCESS) {
+        DEBUG(1, ("Failed to remove connection callback.\n"));
+    } else {
+        DEBUG(9, ("Successfully removed connection callback.\n"));
+    }
+    return lret;
+}
+
+static int sdap_ldap_connect_callback_add(LDAP *ld, Sockbuf *sb,
+                                          LDAPURLDesc *srv,
+                                          struct sockaddr *addr,
+                                          struct ldap_conncb *ctx)
+{
+    int ret;
+    ber_socket_t ber_fd;
+    struct fd_event_item *fd_event_item;
+    struct ldap_cb_data *cb_data = talloc_get_type(ctx->lc_arg,
+                                                   struct ldap_cb_data);
+
+    if (cb_data == NULL) {
+        DEBUG(1, ("sdap_ldap_connect_callback_add called without "
+                  "callback data.\n"));
+        return EINVAL;
+    }
+
+    ret = ber_sockbuf_ctrl(sb, LBER_SB_OPT_GET_FD, &ber_fd);
+    if (ret == -1) {
+        DEBUG(1, ("ber_sockbuf_ctrl failed.\n"));
+        return EINVAL;
+    }
+    DEBUG(9, ("New LDAP connection to [%s] with fd [%d].\n",
+              ldap_url_desc2str(srv), ber_fd));
+
+    fd_event_item = talloc_zero(cb_data, struct fd_event_item);
+    if (fd_event_item == NULL) {
+        DEBUG(1, ("talloc failed.\n"));
+        return ENOMEM;
+    }
+
+    fd_event_item->fde = tevent_add_fd(cb_data->ev, fd_event_item, ber_fd,
+                                       TEVENT_FD_READ, sdap_ldap_result,
+                                       cb_data->sh);
+    if (fd_event_item->fde == NULL) {
+        DEBUG(1, ("tevent_add_fd failed.\n"));
+        talloc_free(fd_event_item);
+        return ENOMEM;
+    }
+    fd_event_item->fd = ber_fd;
+
+    DLIST_ADD(cb_data->fd_list, fd_event_item);
+
+    return LDAP_SUCCESS;
+}
+
+static void sdap_ldap_connect_callback_del(LDAP *ld, Sockbuf *sb,
+                                           struct ldap_conncb *ctx)
+{
+    int ret;
+    ber_socket_t ber_fd;
+    struct fd_event_item *fd_event_item;
+    struct ldap_cb_data *cb_data = talloc_get_type(ctx->lc_arg,
+                                                   struct ldap_cb_data);
+
+    if (sb == NULL || cb_data == NULL) {
+        return;
+    }
+
+    ret = ber_sockbuf_ctrl(sb, LBER_SB_OPT_GET_FD, &ber_fd);
+    if (ret == -1) {
+        DEBUG(1, ("ber_sockbuf_ctrl failed.\n"));
+        return;
+    }
+    DEBUG(9, ("Closing LDAP connection with fd [%d].\n", ber_fd));
+
+    DLIST_FOR_EACH(fd_event_item, cb_data->fd_list) {
+        if (fd_event_item->fd == ber_fd) {
+            break;
+        }
+    }
+    if (fd_event_item == NULL) {
+        DEBUG(1, ("No event for fd [%d] found.\n", ber_fd));
+        return;
+    }
+
+    DLIST_REMOVE(cb_data->fd_list, fd_event_item);
+    talloc_zfree(fd_event_item);
+
+    return;
+}
+
+#else
+
+static int get_fd_from_ldap(LDAP *ldap, int *fd)
+{
+    int ret;
+
+    ret = ldap_get_option(ldap, LDAP_OPT_DESC, fd);
+    if (ret != LDAP_OPT_SUCCESS) {
+        DEBUG(1, ("Failed to get fd from ldap!!\n"));
+        *fd = -1;
+        return EIO;
+    }
+
+    return EOK;
+}
+
+static int sdap_install_ldap_callbacks(struct sdap_handle *sh,
+                                       struct tevent_context *ev)
+{
+    int fd;
+    int ret;
+
+    if (sh->sdap_fd_events) {
+        DEBUG(1, ("sdap_install_ldap_callbacks is called with already "
+                  "initialized sdap_fd_events.\n"));
+        return EINVAL;
+    }
+
+    sh->sdap_fd_events = talloc_zero(sh, struct sdap_fd_events);
+    if (!sh->sdap_fd_events) {
+        DEBUG(1, ("talloc_zero failed.\n"));
+        return ENOMEM;
+    }
+
+    ret = get_fd_from_ldap(sh->ldap, &fd);
+    if (ret) return ret;
+
+    sh->sdap_fd_events->fde = tevent_add_fd(ev, sh->sdap_fd_events, fd,
+                                            TEVENT_FD_READ, sdap_ldap_result,
+                                            sh);
+    if (!sh->sdap_fd_events->fde) {
+        talloc_zfree(sh->sdap_fd_events);
+        return ENOMEM;
+    }
+
+    DEBUG(8, ("Trace: sh[%p], connected[%d], ops[%p], fde[%p], ldap[%p]\n",
+              sh, (int)sh->connected, sh->ops, sh->sdap_fd_events->fde,
+              sh->ldap));
+
+    return EOK;
+}
+
+#endif
+
+
+errno_t setup_ldap_connection_callbacks(struct sdap_handle *sh,
+                                        struct tevent_context *ev)
+{
+#ifdef HAVE_LDAP_CONNCB
+    int ret;
+    struct ldap_cb_data *cb_data;
+
+    sh->sdap_fd_events = talloc_zero(sh, struct sdap_fd_events);
+    if (sh->sdap_fd_events == NULL) {
+        DEBUG(1, ("talloc_zero failed.\n"));
+        ret = ENOMEM;
+        goto fail;
+    }
+
+    sh->sdap_fd_events->conncb = talloc_zero(sh->sdap_fd_events,
+                                             struct ldap_conncb);
+    if (sh->sdap_fd_events->conncb == NULL) {
+        DEBUG(1, ("talloc_zero failed.\n"));
+        ret = ENOMEM;
+        goto fail;
+    }
+
+    cb_data = talloc_zero(sh->sdap_fd_events->conncb, struct ldap_cb_data);
+    if (cb_data == NULL) {
+        DEBUG(1, ("talloc_zero failed.\n"));
+        ret = ENOMEM;
+        goto fail;
+    }
+    cb_data->sh = sh;
+    cb_data->ev = ev;
+
+    sh->sdap_fd_events->conncb->lc_add = sdap_ldap_connect_callback_add;
+    sh->sdap_fd_events->conncb->lc_del = sdap_ldap_connect_callback_del;
+    sh->sdap_fd_events->conncb->lc_arg = cb_data;
+
+    ret = ldap_set_option(sh->ldap, LDAP_OPT_CONNECT_CB,
+                          sh->sdap_fd_events->conncb);
+    if (ret != LDAP_OPT_SUCCESS) {
+        DEBUG(1, ("Failed to set connection callback\n"));
+        ret = EFAULT;
+        goto fail;
+    }
+
+    talloc_set_destructor((TALLOC_CTX *) sh->sdap_fd_events->conncb,
+                          remove_connection_callback);
+
+    return EOK;
+
+fail:
+    talloc_zfree(sh->sdap_fd_events);
+    return ret;
+#else
+    DEBUG(9, ("LDAP connection callbacks are not supported.\n"));
+    return EOK;
+#endif
+}
+
+errno_t sdap_set_connected(struct sdap_handle *sh, struct tevent_context *ev)
+{
+    int ret = EOK;
+
+    sh->connected = true;
+
+#ifndef HAVE_LDAP_CONNCB
+    ret = sdap_install_ldap_callbacks(sh, ev);
+#endif
+
+    return ret;
+}