1 /* $NetBSD: txn.c,v 1.3 2021/08/14 16:14:58 christos Exp $ */
2
3 /* txn.c - LDAP Transactions */
4 /* $OpenLDAP$ */
5 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
6 *
7 * Copyright 1998-2021 The OpenLDAP Foundation.
8 * All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted only as authorized by the OpenLDAP
12 * Public License.
13 *
14 * A copy of this license is available in the file LICENSE in the
15 * top-level directory of the distribution or, alternatively, at
16 * <http://www.OpenLDAP.org/license.html>.
17 */
18
19 #include <sys/cdefs.h>
20 __RCSID("$NetBSD: txn.c,v 1.3 2021/08/14 16:14:58 christos Exp $");
21
22 #include "portable.h"
23
24 #include <stdio.h>
25
26 #include <ac/socket.h>
27 #include <ac/string.h>
28 #include <ac/unistd.h>
29
30 #include "slap.h"
31
32 #include <lber_pvt.h>
33 #include <lutil.h>
34
35 const struct berval slap_EXOP_TXN_START = BER_BVC(LDAP_EXOP_TXN_START);
36 const struct berval slap_EXOP_TXN_END = BER_BVC(LDAP_EXOP_TXN_END);
37
txn_start_extop(Operation * op,SlapReply * rs)38 int txn_start_extop(
39 Operation *op, SlapReply *rs )
40 {
41 int rc;
42 struct berval *bv;
43
44 Debug( LDAP_DEBUG_STATS, "%s TXN START\n",
45 op->o_log_prefix );
46
47 if( op->ore_reqdata != NULL ) {
48 rs->sr_text = "no request data expected";
49 return LDAP_PROTOCOL_ERROR;
50 }
51
52 op->o_bd = op->o_conn->c_authz_backend;
53 if( backend_check_restrictions( op, rs,
54 (struct berval *)&slap_EXOP_TXN_START ) != LDAP_SUCCESS )
55 {
56 return rs->sr_err;
57 }
58
59 /* acquire connection lock */
60 ldap_pvt_thread_mutex_lock( &op->o_conn->c_mutex );
61
62 if( op->o_conn->c_txn != CONN_TXN_INACTIVE ) {
63 rs->sr_text = "Too many transactions";
64 rc = LDAP_BUSY;
65 goto done;
66 }
67
68 assert( op->o_conn->c_txn_backend == NULL );
69 op->o_conn->c_txn = CONN_TXN_SPECIFY;
70
71 bv = (struct berval *) ch_malloc( sizeof (struct berval) );
72 bv->bv_len = 0;
73 bv->bv_val = NULL;
74
75 rs->sr_rspdata = bv;
76 rc = LDAP_SUCCESS;
77
78 done:
79 /* release connection lock */
80 ldap_pvt_thread_mutex_unlock( &op->o_conn->c_mutex );
81 return rc;
82 }
83
txn_spec_ctrl(Operation * op,SlapReply * rs,LDAPControl * ctrl)84 int txn_spec_ctrl(
85 Operation *op, SlapReply *rs, LDAPControl *ctrl )
86 {
87 if ( !ctrl->ldctl_iscritical ) {
88 rs->sr_text = "txnSpec control must be marked critical";
89 return LDAP_PROTOCOL_ERROR;
90 }
91 if( op->o_txnSpec ) {
92 rs->sr_text = "txnSpec control provided multiple times";
93 return LDAP_PROTOCOL_ERROR;
94 }
95
96 if ( ctrl->ldctl_value.bv_val == NULL ) {
97 rs->sr_text = "no transaction identifier provided";
98 return LDAP_PROTOCOL_ERROR;
99 }
100 if ( ctrl->ldctl_value.bv_len != 0 ) {
101 rs->sr_text = "invalid transaction identifier";
102 return LDAP_TXN_ID_INVALID;
103 }
104
105 if ( op->o_preread ) { /* temporary limitation */
106 rs->sr_text = "cannot perform pre-read in transaction";
107 return LDAP_UNWILLING_TO_PERFORM;
108 }
109 if ( op->o_postread ) { /* temporary limitation */
110 rs->sr_text = "cannot perform post-read in transaction";
111 return LDAP_UNWILLING_TO_PERFORM;
112 }
113
114 op->o_txnSpec = SLAP_CONTROL_CRITICAL;
115 return LDAP_SUCCESS;
116 }
117
118 typedef struct txn_rctrls {
119 struct txn_rctrls *tr_next;
120 ber_int_t tr_msgid;
121 LDAPControl ** tr_ctrls;
122 } txn_rctrls;
123
txn_result(Operation * op,SlapReply * rs)124 static int txn_result( Operation *op, SlapReply *rs )
125 {
126 if ( rs->sr_ctrls ) {
127 txn_rctrls **t0, *tr;
128 for ( t0 = (txn_rctrls **) &op->o_callback->sc_private; *t0;
129 t0 = &(*t0)->tr_next )
130 ;
131 tr = op->o_tmpalloc( sizeof( txn_rctrls ), op->o_tmpmemctx );
132 tr->tr_next = NULL;
133 *t0 = tr;
134 tr->tr_msgid = op->o_msgid;
135 tr->tr_ctrls = ldap_controls_dup( rs->sr_ctrls );
136 }
137 return rs->sr_err;
138 }
139
txn_put_ctrls(Operation * op,BerElement * ber,txn_rctrls * tr)140 static int txn_put_ctrls( Operation *op, BerElement *ber, txn_rctrls *tr )
141 {
142 txn_rctrls *next;
143 int i;
144 ber_printf( ber, "{" );
145 for ( ; tr; tr = next ) {
146 next = tr->tr_next;
147 ber_printf( ber, "{it{", tr->tr_msgid, LDAP_TAG_CONTROLS );
148 for ( i = 0; tr->tr_ctrls[i]; i++ )
149 ldap_pvt_put_control( tr->tr_ctrls[i], ber );
150 ber_printf( ber, "}}" );
151 ldap_controls_free( tr->tr_ctrls );
152 op->o_tmpfree( tr, op->o_tmpmemctx );
153 }
154 ber_printf( ber, "}" );
155 return 0;
156 }
157
txn_end_extop(Operation * op,SlapReply * rs)158 int txn_end_extop(
159 Operation *op, SlapReply *rs )
160 {
161 int rc;
162 BerElementBuffer berbuf;
163 BerElement *ber = (BerElement *)&berbuf;
164 ber_tag_t tag;
165 ber_len_t len;
166 ber_int_t commit=1;
167 struct berval txnid;
168 Operation *o, *p;
169 Connection *c = op->o_conn;
170
171 Debug( LDAP_DEBUG_STATS, "%s TXN END\n",
172 op->o_log_prefix );
173
174 if( op->ore_reqdata == NULL ) {
175 rs->sr_text = "request data expected";
176 return LDAP_PROTOCOL_ERROR;
177 }
178 if( op->ore_reqdata->bv_len == 0 ) {
179 rs->sr_text = "empty request data";
180 return LDAP_PROTOCOL_ERROR;
181 }
182
183 op->o_bd = c->c_authz_backend;
184 if( backend_check_restrictions( op, rs,
185 (struct berval *)&slap_EXOP_TXN_END ) != LDAP_SUCCESS )
186 {
187 return rs->sr_err;
188 }
189
190 ber_init2( ber, op->ore_reqdata, 0 );
191
192 tag = ber_scanf( ber, "{" /*}*/ );
193 if( tag == LBER_ERROR ) {
194 rs->sr_text = "request data decoding error";
195 return LDAP_PROTOCOL_ERROR;
196 }
197
198 tag = ber_peek_tag( ber, &len );
199 if( tag == LBER_BOOLEAN ) {
200 tag = ber_scanf( ber, "b", &commit );
201 if( tag == LBER_ERROR ) {
202 rs->sr_text = "request data decoding error";
203 return LDAP_PROTOCOL_ERROR;
204 }
205 }
206
207 tag = ber_scanf( ber, /*{*/ "m}", &txnid );
208 if( tag == LBER_ERROR ) {
209 rs->sr_text = "request data decoding error";
210 return LDAP_PROTOCOL_ERROR;
211 }
212
213 if( txnid.bv_len ) {
214 rs->sr_text = "invalid transaction identifier";
215 return LDAP_TXN_ID_INVALID;
216 }
217
218 /* acquire connection lock */
219 ldap_pvt_thread_mutex_lock( &c->c_mutex );
220
221 if( c->c_txn != CONN_TXN_SPECIFY ) {
222 rs->sr_text = "invalid transaction identifier";
223 rc = LDAP_TXN_ID_INVALID;
224 goto done;
225 }
226 c->c_txn = CONN_TXN_SETTLE;
227
228 if( commit ) {
229 slap_callback cb = {0};
230 OpExtra *txn = NULL;
231 if ( op->o_abandon ) {
232 goto drain;
233 }
234
235 if( LDAP_STAILQ_EMPTY(&c->c_txn_ops) ) {
236 /* no updates to commit */
237 rs->sr_text = "no updates to commit";
238 rc = LDAP_OPERATIONS_ERROR;
239 goto settled;
240 }
241
242 cb.sc_response = txn_result;
243 LDAP_STAILQ_FOREACH( o, &c->c_txn_ops, o_next ) {
244 o->o_bd = c->c_txn_backend;
245 p = o;
246 if ( !txn ) {
247 rc = o->o_bd->bd_info->bi_op_txn(o, SLAP_TXN_BEGIN, &txn );
248 if ( rc ) {
249 rs->sr_text = "couldn't start DB transaction";
250 rc = LDAP_OTHER;
251 goto drain;
252 }
253 } else {
254 LDAP_SLIST_INSERT_HEAD( &o->o_extra, txn, oe_next );
255 }
256 cb.sc_next = o->o_callback;
257 o->o_callback = &cb;
258 {
259 SlapReply rs = {REP_RESULT};
260 int opidx = slap_req2op( o->o_tag );
261 assert( opidx != SLAP_OP_LAST );
262 o->o_threadctx = op->o_threadctx;
263 o->o_tid = op->o_tid;
264 ldap_pvt_thread_mutex_unlock( &c->c_mutex );
265 rc = (&o->o_bd->bd_info->bi_op_bind)[opidx]( o, &rs );
266 ldap_pvt_thread_mutex_lock( &c->c_mutex );
267 }
268 if ( rc ) {
269 struct berval *bv = NULL;
270 BerElementBuffer berbuf;
271 BerElement *ber = (BerElement *)&berbuf;
272
273 ber_init_w_nullc( ber, LBER_USE_DER );
274 ber_printf( ber, "{i", o->o_msgid );
275 if ( cb.sc_private )
276 txn_put_ctrls( op, ber, cb.sc_private );
277 ber_printf( ber, "}" );
278 ber_flatten( ber, &bv );
279 ber_free_buf( ber );
280 rs->sr_rspdata = bv;
281 o->o_bd->bd_info->bi_op_txn(o, SLAP_TXN_ABORT, &txn );
282 goto drain;
283 }
284 }
285 if ( cb.sc_private ) {
286 struct berval *bv = NULL;
287 BerElementBuffer berbuf;
288 BerElement *ber = (BerElement *)&berbuf;
289
290 ber_init_w_nullc( ber, LBER_USE_DER );
291 ber_printf( ber, "{" );
292 txn_put_ctrls( op, ber, cb.sc_private );
293 ber_printf( ber, "}" );
294 ber_flatten( ber, &bv );
295 ber_free_buf( ber );
296 rs->sr_rspdata = bv;
297 }
298 o = p;
299 rc = o->o_bd->bd_info->bi_op_txn(o, SLAP_TXN_COMMIT, &txn );
300 if ( rc ) {
301 rs->sr_text = "transaction commit failed";
302 rc = LDAP_OTHER;
303 }
304 } else {
305 rs->sr_text = "transaction aborted";
306 rc = LDAP_SUCCESS;
307 }
308
309 drain:
310 /* drain txn ops list */
311 while (( o = LDAP_STAILQ_FIRST( &c->c_txn_ops )) != NULL ) {
312 LDAP_STAILQ_REMOVE_HEAD( &c->c_txn_ops, o_next );
313 LDAP_STAILQ_NEXT( o, o_next ) = NULL;
314 slap_op_free( o, NULL );
315 }
316
317 settled:
318 assert( LDAP_STAILQ_EMPTY(&c->c_txn_ops) );
319 assert( c->c_txn == CONN_TXN_SETTLE );
320 c->c_txn = CONN_TXN_INACTIVE;
321 c->c_txn_backend = NULL;
322
323 done:
324 /* release connection lock */
325 ldap_pvt_thread_mutex_unlock( &c->c_mutex );
326
327 return rc;
328 }
329
txn_preop(Operation * op,SlapReply * rs)330 int txn_preop( Operation *op, SlapReply *rs )
331 {
332 /* acquire connection lock */
333 ldap_pvt_thread_mutex_lock( &op->o_conn->c_mutex );
334 if( op->o_conn->c_txn == CONN_TXN_INACTIVE ) {
335 rs->sr_text = "invalid transaction identifier";
336 rs->sr_err = LDAP_TXN_ID_INVALID;
337 goto txnReturn;
338 }
339
340 if( op->o_conn->c_txn_backend == NULL ) {
341 op->o_conn->c_txn_backend = op->o_bd;
342
343 } else if( op->o_conn->c_txn_backend != op->o_bd ) {
344 rs->sr_text = "transaction cannot span multiple database contexts";
345 rs->sr_err = LDAP_AFFECTS_MULTIPLE_DSAS;
346 goto txnReturn;
347 }
348
349 if ( !SLAP_TXNS( op->o_bd )) {
350 rs->sr_text = "backend doesn't support transactions";
351 rs->sr_err = LDAP_UNWILLING_TO_PERFORM;
352 goto txnReturn;
353 }
354
355 /* insert operation into transaction */
356 LDAP_STAILQ_REMOVE( &op->o_conn->c_ops, op, Operation, o_next );
357 LDAP_STAILQ_INSERT_TAIL( &op->o_conn->c_txn_ops, op, o_next );
358
359 txnReturn:
360 /* release connection lock */
361 ldap_pvt_thread_mutex_unlock( &op->o_conn->c_mutex );
362
363 if ( op->o_tag != LDAP_REQ_EXTENDED )
364 send_ldap_result( op, rs );
365 if ( !rs->sr_err )
366 rs->sr_err = LDAP_TXN_SPECIFY_OKAY;
367 return rs->sr_err;
368 }
369