diff options
Diffstat (limited to 'servers/slapd/cancel.c')
-rw-r--r-- | servers/slapd/cancel.c | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/servers/slapd/cancel.c b/servers/slapd/cancel.c new file mode 100644 index 0000000..22b5232 --- /dev/null +++ b/servers/slapd/cancel.c @@ -0,0 +1,162 @@ +/* cancel.c - LDAP cancel extended operation */ +/* $OpenLDAP$ */ +/* This work is part of OpenLDAP Software <http://www.openldap.org/>. + * + * Copyright 1998-2021 The OpenLDAP Foundation. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted only as authorized by the OpenLDAP + * Public License. + * + * A copy of this license is available in the file LICENSE in the + * top-level directory of the distribution or, alternatively, at + * <http://www.OpenLDAP.org/license.html>. + */ + +#include "portable.h" + +#include <stdio.h> + +#include <ac/socket.h> +#include <ac/string.h> +#include <ac/unistd.h> + +#include "slap.h" + +#include <lber_pvt.h> +#include <lutil.h> + +const struct berval slap_EXOP_CANCEL = BER_BVC(LDAP_EXOP_CANCEL); + +int cancel_extop( Operation *op, SlapReply *rs ) +{ + Operation *o; + int rc; + int opid; + BerElementBuffer berbuf; + BerElement *ber = (BerElement *)&berbuf; + + assert( ber_bvcmp( &slap_EXOP_CANCEL, &op->ore_reqoid ) == 0 ); + + if ( op->ore_reqdata == NULL ) { + rs->sr_text = "no message ID supplied"; + return LDAP_PROTOCOL_ERROR; + } + + if ( op->ore_reqdata->bv_len == 0 ) { + rs->sr_text = "empty request data field"; + return LDAP_PROTOCOL_ERROR; + } + + /* ber_init2 uses reqdata directly, doesn't allocate new buffers */ + ber_init2( ber, op->ore_reqdata, 0 ); + + if ( ber_scanf( ber, "{i}", &opid ) == LBER_ERROR ) { + rs->sr_text = "message ID parse failed"; + return LDAP_PROTOCOL_ERROR; + } + + Statslog( LDAP_DEBUG_STATS, "%s CANCEL msg=%d\n", + op->o_log_prefix, opid, 0, 0, 0 ); + + if ( opid < 0 ) { + rs->sr_text = "message ID invalid"; + return LDAP_PROTOCOL_ERROR; + } + + if ( opid == op->o_msgid ) { + op->o_cancel = SLAP_CANCEL_DONE; + return LDAP_SUCCESS; + } + + ldap_pvt_thread_mutex_lock( &op->o_conn->c_mutex ); + + if ( op->o_abandon ) { + /* FIXME: Should instead reject the cancel/abandon of this op, but + * it seems unsafe to reset op->o_abandon once it is set. ITS#6138. + */ + rc = LDAP_OPERATIONS_ERROR; + rs->sr_text = "tried to abandon or cancel this operation"; + goto out; + } + + LDAP_STAILQ_FOREACH( o, &op->o_conn->c_pending_ops, o_next ) { + if ( o->o_msgid == opid ) { + /* TODO: We could instead remove the cancelled operation + * from c_pending_ops like Abandon does, and send its + * response here. Not if it is pending because of a + * congested connection though. + */ + rc = LDAP_CANNOT_CANCEL; + rs->sr_text = "too busy for Cancel, try Abandon instead"; + goto out; + } + } + + LDAP_STAILQ_FOREACH( o, &op->o_conn->c_ops, o_next ) { + if ( o->o_msgid == opid ) { + break; + } + } + + if ( o == NULL ) { + rc = LDAP_NO_SUCH_OPERATION; + rs->sr_text = "message ID not found"; + + } else if ( o->o_tag == LDAP_REQ_BIND + || o->o_tag == LDAP_REQ_UNBIND + || o->o_tag == LDAP_REQ_ABANDON ) { + rc = LDAP_CANNOT_CANCEL; + + } else if ( o->o_cancel != SLAP_CANCEL_NONE ) { + rc = LDAP_OPERATIONS_ERROR; + rs->sr_text = "message ID already being cancelled"; + +#if 0 + } else if ( o->o_abandon ) { + /* TODO: Would this break something when + * o_abandon="suppress response"? (ITS#6138) + */ + rc = LDAP_TOO_LATE; +#endif + + } else { + rc = LDAP_SUCCESS; + o->o_cancel = SLAP_CANCEL_REQ; + o->o_abandon = 1; + } + + out: + ldap_pvt_thread_mutex_unlock( &op->o_conn->c_mutex ); + + if ( rc == LDAP_SUCCESS ) { + LDAP_STAILQ_FOREACH( op->o_bd, &backendDB, be_next ) { + if( !op->o_bd->be_cancel ) continue; + + op->oq_cancel.rs_msgid = opid; + if ( op->o_bd->be_cancel( op, rs ) == LDAP_SUCCESS ) { + return LDAP_SUCCESS; + } + } + + do { + /* Fake a cond_wait with thread_yield, then + * verify the result properly mutex-protected. + */ + while ( o->o_cancel == SLAP_CANCEL_REQ ) + ldap_pvt_thread_yield(); + ldap_pvt_thread_mutex_lock( &op->o_conn->c_mutex ); + rc = o->o_cancel; + ldap_pvt_thread_mutex_unlock( &op->o_conn->c_mutex ); + } while ( rc == SLAP_CANCEL_REQ ); + + if ( rc == SLAP_CANCEL_ACK ) { + rc = LDAP_SUCCESS; + } + + o->o_cancel = SLAP_CANCEL_DONE; + } + + return rc; +} |