CVE-2020-25719 kdc: Avoid races and multiple DB lookups in s4u2self check
[Samba.git] / source3 / utils / netlookup.c
blobaaf78b0977aff562c8c029770d5fba63167b9fbf
1 /*
2 Unix SMB/CIFS implementation.
4 Name lookup.
6 Copyright (C) Jeremy Allison 2005
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>.
22 #include "includes.h"
23 #include "utils/net.h"
24 #include "rpc_client/cli_pipe.h"
25 #include "../librpc/gen_ndr/ndr_lsa.h"
26 #include "rpc_client/cli_lsarpc.h"
27 #include "libsmb/libsmb.h"
29 /********************************************************
30 Connection cachine struct. Goes away when ctx destroyed.
31 ********************************************************/
33 struct con_struct {
34 bool failed_connect;
35 NTSTATUS err;
36 struct cli_state *cli;
37 struct rpc_pipe_client *lsapipe;
38 struct policy_handle pol;
41 static struct con_struct *cs;
43 /********************************************************
44 Close connection on context destruction.
45 ********************************************************/
47 static int cs_destructor(struct con_struct *p)
49 if (cs->cli) {
50 cli_shutdown(cs->cli);
52 cs = NULL;
53 return 0;
56 /********************************************************
57 Create the connection to localhost.
58 ********************************************************/
60 static struct con_struct *create_cs(struct net_context *c,
61 TALLOC_CTX *ctx, NTSTATUS *perr)
63 NTSTATUS nt_status;
64 struct sockaddr_storage loopback_ss;
65 struct cli_credentials *anon_creds = NULL;
67 *perr = NT_STATUS_OK;
69 if (!interpret_string_addr(&loopback_ss, "127.0.0.1", AI_NUMERICHOST)) {
70 *perr = NT_STATUS_INVALID_PARAMETER;
71 return NULL;
74 if (cs) {
75 if (cs->failed_connect) {
76 *perr = cs->err;
77 return NULL;
79 return cs;
82 cs = talloc(ctx, struct con_struct);
83 if (!cs) {
84 *perr = NT_STATUS_NO_MEMORY;
85 return NULL;
88 anon_creds = cli_credentials_init_anon(cs);
89 if (anon_creds == NULL) {
90 TALLOC_FREE(cs);
91 *perr = NT_STATUS_NO_MEMORY;
92 return NULL;
95 ZERO_STRUCTP(cs);
96 talloc_set_destructor(cs, cs_destructor);
98 nt_status = cli_full_connection_creds(&cs->cli, lp_netbios_name(), lp_netbios_name(),
99 &loopback_ss, 0,
100 "IPC$", "IPC",
101 anon_creds,
102 CLI_FULL_CONNECTION_IPC);
104 if (!NT_STATUS_IS_OK(nt_status)) {
105 DEBUG(2,("create_cs: Connect failed. Error was %s\n", nt_errstr(nt_status)));
106 cs->failed_connect = true;
107 cs->err = nt_status;
108 *perr = nt_status;
109 return NULL;
112 nt_status = cli_rpc_pipe_open_noauth(cs->cli,
113 &ndr_table_lsarpc,
114 &cs->lsapipe);
116 if (!NT_STATUS_IS_OK(nt_status)) {
117 DEBUG(2,("create_cs: open LSA pipe failed. Error was %s\n", nt_errstr(nt_status)));
118 cs->failed_connect = true;
119 cs->err = nt_status;
120 *perr = nt_status;
121 return NULL;
124 nt_status = rpccli_lsa_open_policy(cs->lsapipe, ctx, true,
125 SEC_FLAG_MAXIMUM_ALLOWED,
126 &cs->pol);
128 if (!NT_STATUS_IS_OK(nt_status)) {
129 DEBUG(2,("create_cs: rpccli_lsa_open_policy failed. Error was %s\n", nt_errstr(nt_status)));
130 cs->failed_connect = true;
131 cs->err = nt_status;
132 *perr = nt_status;
133 return NULL;
136 return cs;
139 /********************************************************
140 Do a lookup_sids call to localhost.
141 Check if the local machine is authoritative for this sid. We can't
142 check if this is our SID as that's stored in the root-read-only
143 secrets.tdb.
144 The local smbd will also ask winbindd for us, so we don't have to.
145 ********************************************************/
147 NTSTATUS net_lookup_name_from_sid(struct net_context *c,
148 TALLOC_CTX *ctx,
149 struct dom_sid *psid,
150 const char **ppdomain,
151 const char **ppname)
153 NTSTATUS nt_status;
154 struct con_struct *csp = NULL;
155 char **domains;
156 char **names;
157 enum lsa_SidType *types;
159 *ppdomain = NULL;
160 *ppname = NULL;
162 csp = create_cs(c, ctx, &nt_status);
163 if (csp == NULL) {
164 return nt_status;
167 nt_status = rpccli_lsa_lookup_sids(csp->lsapipe, ctx,
168 &csp->pol,
169 1, psid,
170 &domains,
171 &names,
172 &types);
174 if (!NT_STATUS_IS_OK(nt_status)) {
175 return nt_status;
178 *ppdomain = domains[0];
179 *ppname = names[0];
180 /* Don't care about type here. */
182 /* Converted OK */
183 return NT_STATUS_OK;
186 /********************************************************
187 Do a lookup_names call to localhost.
188 ********************************************************/
190 NTSTATUS net_lookup_sid_from_name(struct net_context *c, TALLOC_CTX *ctx,
191 const char *full_name, struct dom_sid *pret_sid)
193 NTSTATUS nt_status;
194 struct con_struct *csp = NULL;
195 struct dom_sid *sids = NULL;
196 enum lsa_SidType *types = NULL;
198 csp = create_cs(c, ctx, &nt_status);
199 if (csp == NULL) {
200 return nt_status;
203 nt_status = rpccli_lsa_lookup_names(csp->lsapipe, ctx,
204 &csp->pol,
206 &full_name,
207 NULL, 1,
208 &sids, &types);
210 if (!NT_STATUS_IS_OK(nt_status)) {
211 return nt_status;
214 *pret_sid = sids[0];
216 /* Converted OK */
217 return NT_STATUS_OK;