rpms
/
sssd
7
0
Fork 0
Code Issues Pull Requests Releases Activity
sssd/SOURCES/0003-ad-filter-trusted-doma...

188 lines
7.2 KiB
Diff
Raw Blame History

From 4c48c4a7792961cf8a228c76975ac370d32904e1 Mon Sep 17 00:00:00 2001
From: Sumit Bose <sbose@redhat.com>
Date: Wed, 6 Oct 2021 13:03:27 +0200
Subject: [PATCH] ad: filter trusted domains
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
The fix for https://github.com/SSSD/sssd/issues/5528 might discover
domains which are not trusted (one-way trust) or are from a different
forest (direct trust). Both should be ignored because they are not
trusted or can currently not be handled properly. This patch filters out
those domains.
Resolves: https://github.com/SSSD/sssd/issues/5819
Reviewed-by: Alexey Tikhonov <atikhono@redhat.com>
Reviewed-by: Pavel Březina <pbrezina@redhat.com>
---
src/providers/ad/ad_subdomains.c | 104 +++++++++++++++++++++++++++++--
1 file changed, 99 insertions(+), 5 deletions(-)
diff --git a/src/providers/ad/ad_subdomains.c b/src/providers/ad/ad_subdomains.c
index 3eb49c93f..ac463026f 100644
--- a/src/providers/ad/ad_subdomains.c
+++ b/src/providers/ad/ad_subdomains.c
@@ -46,6 +46,7 @@
#define AD_AT_TRUST_PARTNER "trustPartner"
#define AD_AT_TRUST_ATTRS "trustAttributes"
#define AD_AT_DOMAIN_NAME "cn"
+#define AD_AT_TRUST_DIRECTION "trustDirection"
/* trustType=2 denotes uplevel (NT5 and later) trusted domains. See
* http://msdn.microsoft.com/en-us/library/windows/desktop/ms680342%28v=vs.85%29.aspx
@@ -69,6 +70,12 @@
/* do not refresh more often than every 5 seconds for now */
#define AD_SUBDOMAIN_REFRESH_LIMIT 5
+/* Flags of trustAttributes attribute, see MS-ADTS 6.1.6.7.9 for details */
+#define TRUST_ATTRIBUTE_WITHIN_FOREST 0x00000020
+
+/* Flags for trustDirection attribute, see MS-ADTS 6.1.6.7.12 for details */
+#define TRUST_DIRECTION_OUTBOUND 0x00000002
+
static void
ad_disable_gc(struct ad_options *ad_options)
{
@@ -646,6 +653,85 @@ done:
return ret;
}
+/* When reading trusted domains from the local DC we are basically interested
+ * in domains from the local forest we are trusting, i.e. users from this
+ * domain can connect to us. To not unnecessarily bloat the list of domains
+ * and make multi-domain searches slow we filter domains from other forest and
+ * domains we do not trust.
+ * In future we might add config options to broaden the scope and allow more
+ * domains.
+ * If ad_filter_domains() returns successfully with EOK in input array is not
+ * valid anymore and should be freed by the caller. */
+static errno_t ad_filter_domains(TALLOC_CTX *mem_ctx,
+ struct sysdb_attrs **subdomains,
+ size_t num_subdomains,
+ struct sysdb_attrs ***_sd_out,
+ size_t *_num_sd_out)
+{
+ int ret;
+ size_t c;
+ uint32_t tmp_uint32_t;
+ const char *value;
+ struct sysdb_attrs **sd_out;
+ size_t num_sd_out = 0;
+
+ sd_out = talloc_zero_array(mem_ctx, struct sysdb_attrs *,
+ num_subdomains + 1);
+ if (sd_out == NULL) {
+ DEBUG(SSSDBG_OP_FAILURE,
+ "Failed to allocate memory for sub-domain list.\n");
+ return ENOMEM;
+ }
+
+ for (c = 0; c < num_subdomains; c++) {
+ ret = sysdb_attrs_get_string(subdomains[c], AD_AT_TRUST_PARTNER,
+ &value);
+ if (ret != EOK) {
+ DEBUG(SSSDBG_OP_FAILURE, "sysdb_attrs_get_string failed.\n");
+ talloc_free(sd_out);
+ return ret;
+ }
+
+ /* Ignore direct trusts to domains from other forests
+ * (TRUST_ATTRIBUTE_WITHIN_FOREST is not set) or domains we do not
+ * trust (TRUST_DIRECTION_OUTBOUND is not set) */
+
+ tmp_uint32_t = 0;
+ ret = sysdb_attrs_get_uint32_t(subdomains[c], AD_AT_TRUST_ATTRS,
+ &tmp_uint32_t);
+ if (ret != EOK
+ || (tmp_uint32_t & TRUST_ATTRIBUTE_WITHIN_FOREST) == 0) {
+ DEBUG(SSSDBG_FUNC_DATA,
+ "TRUST_ATTRIBUTE_WITHIN_FOREST not set for [%s].\n",
+ value);
+ continue;
+ }
+
+ tmp_uint32_t = 0;
+ ret = sysdb_attrs_get_uint32_t(subdomains[c], AD_AT_TRUST_DIRECTION,
+ &tmp_uint32_t);
+ if (ret != EOK
+ || (tmp_uint32_t & TRUST_DIRECTION_OUTBOUND) == 0) {
+ DEBUG(SSSDBG_FUNC_DATA,
+ "TRUST_DIRECTION_OUTBOUND not set for [%s].\n",
+ value);
+ continue;
+ }
+
+ sd_out[num_sd_out] = subdomains[c];
+ num_sd_out++;
+ }
+
+ for (c = 0; c < num_sd_out; c++) {
+ sd_out[c] = talloc_steal(sd_out, sd_out[c]);
+ }
+
+ *_sd_out = sd_out;
+ *_num_sd_out = num_sd_out;
+
+ return EOK;
+}
+
/* How many times we keep a domain not found during searches before it will be
* removed. */
#define MAX_NOT_FOUND 6
@@ -1125,7 +1211,7 @@ static void ad_get_slave_domain_connect_done(struct tevent_req *subreq)
errno_t ret;
const char *attrs[] = { AD_AT_FLATNAME, AD_AT_TRUST_PARTNER,
AD_AT_SID, AD_AT_TRUST_TYPE,
- AD_AT_TRUST_ATTRS, NULL };
+ AD_AT_TRUST_ATTRS, AD_AT_TRUST_DIRECTION, NULL };
req = tevent_req_callback_data(subreq, struct tevent_req);
state = tevent_req_data(req, struct ad_get_slave_domain_state);
@@ -1333,7 +1419,7 @@ ad_get_root_domain_send(TALLOC_CTX *mem_ctx,
struct sdap_options *opts;
errno_t ret;
const char *attrs[] = { AD_AT_FLATNAME, AD_AT_TRUST_PARTNER,
- AD_AT_SID, AD_AT_TRUST_TYPE,
+ AD_AT_SID, AD_AT_TRUST_TYPE, AD_AT_TRUST_DIRECTION,
AD_AT_TRUST_ATTRS, AD_AT_DOMAIN_NAME, NULL };
req = tevent_req_create(mem_ctx, &state, struct ad_get_root_domain_state);
@@ -1411,13 +1497,15 @@ static void ad_get_root_domain_done(struct tevent_req *subreq)
struct ad_get_root_domain_state *state;
errno_t ret;
bool has_changes = false;
+ struct sysdb_attrs **unfiltered_reply;
+ size_t unfiltered_reply_count;
req = tevent_req_callback_data(subreq, struct tevent_req);
state = tevent_req_data(req, struct ad_get_root_domain_state);
ret = sdap_search_bases_return_first_recv(subreq, state,
- &state->reply_count,
- &state->reply);
+ &unfiltered_reply_count,
+ &unfiltered_reply);
talloc_zfree(subreq);
if (ret != EOK) {
DEBUG(SSSDBG_OP_FAILURE, "Unable to lookup forest root information "
@@ -1425,7 +1513,13 @@ static void ad_get_root_domain_done(struct tevent_req *subreq)
goto done;
}
- find_domain(state->reply_count, state->reply, state->forest);
+ ret = ad_filter_domains(state, unfiltered_reply, unfiltered_reply_count,
+ &state->reply, &state->reply_count);
+ if (ret != EOK) {
+ DEBUG(SSSDBG_OP_FAILURE,
+ "Failed to filter list of returned domains.\n");
+ goto done;
+ }
if (state->reply_count == 0
|| find_domain(state->reply_count, state->reply,
--
2.26.3
Reference in New Issue View Git Blame Copy Permalink