From 364b87f5875956361200ce7a4bb763bc8d6af02a Mon Sep 17 00:00:00 2001 From: Emmanuel Dreyfus Date: Mon, 19 May 2008 22:44:08 +0000 Subject: [PATCH] Here is slapo-nops, used to remove idempotent operations (i.e.: replacing an attribute values by the exact same values) --- contrib/slapd-modules/nops/Makefile | 9 ++ contrib/slapd-modules/nops/nops.c | 168 ++++++++++++++++++++++++ contrib/slapd-modules/nops/slapo-nops.5 | 32 +++++ 3 files changed, 209 insertions(+) create mode 100644 contrib/slapd-modules/nops/Makefile create mode 100644 contrib/slapd-modules/nops/nops.c create mode 100644 contrib/slapd-modules/nops/slapo-nops.5 diff --git a/contrib/slapd-modules/nops/Makefile b/contrib/slapd-modules/nops/Makefile new file mode 100644 index 0000000000..827a5ba221 --- /dev/null +++ b/contrib/slapd-modules/nops/Makefile @@ -0,0 +1,9 @@ +CPPFLAGS+=-I../../../include -I../../../servers/slapd + +all: nops.so + +nops.so: nops.c + $(CC) -shared $(CPPFLAGS) -Wall -o $@ $? + +clean: + rm nops.so diff --git a/contrib/slapd-modules/nops/nops.c b/contrib/slapd-modules/nops/nops.c new file mode 100644 index 0000000000..0914cf4695 --- /dev/null +++ b/contrib/slapd-modules/nops/nops.c @@ -0,0 +1,168 @@ +/* $OpenLDAP$ */ +/* nops.c - Overlay to filter idempotent operations */ +/* + * Copyright 2008 Emmanuel Dreyfus + * 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 + * . + */ +#include "portable.h" + +#ifdef SLAPD_OVER_NOPS + +#include + +#include +#include + +#include "lutil.h" +#include "slap.h" +#include "config.h" + +static ConfigDriver nops_cf_gen; + +static int nops_cf_gen( ConfigArgs *c ) { return 0; } + +static void +nops_rm_mod( Modifications **mods, Modifications *mod ) { + Modifications *next, *m; + + next = mod->sml_next; + if (*mods == mod) { + *mods = next; + } else { + Modifications *m; + + for (m = *mods; m; m = m->sml_next) { + if (m->sml_next == mod) { + m->sml_next = next; + break; + } + } + } + + for (m = *mods; m; m = m->sml_next) + mod->sml_next = NULL; + slap_mods_free(mod, 1); + + return; +} + +static int +nops_modify( Operation *op, SlapReply *rs ) +{ + slap_overinst *on = (slap_overinst *) op->o_bd->bd_info; + Backend *be = op->o_bd; + Entry *target_entry = NULL; + Modifications *m; + int rc; + + if ((m = op->orm_modlist) == NULL) { + op->o_bd->bd_info = (BackendInfo *)(on->on_info); + send_ldap_error(op, rs, LDAP_INVALID_SYNTAX, + "nops() got null orm_modlist"); + return(rs->sr_err); + } + + op->o_bd = on->on_info->oi_origdb; + rc = be_entry_get_rw(op, &op->o_req_ndn, NULL, NULL, 0, &target_entry); + op->o_bd = be; + + if (rc != 0 || target_entry == NULL) + return 0; + + /* + * For each attribute modification, check if the + * modification and the old entry are the same. + */ + while (m) { + int i, j; + int found; + Attribute *a; + BerVarray bm; + BerVarray bt; + Modifications *mc; + + mc = m; + m = m->sml_next; + + /* Check only replace sub-operations */ + if ((mc->sml_op & LDAP_MOD_OP) != LDAP_MOD_REPLACE) + continue; + + /* If there is no values, skip */ + if (((bm = mc->sml_values ) == NULL ) || (bm[0].bv_val == NULL)) + continue; + + /* If the attribute does not exist in old entry, skip */ + if ((a = attr_find(target_entry->e_attrs, mc->sml_desc)) == NULL) + continue; + if ((bt = a->a_vals) == NULL) + continue; + + /* For each value replaced, do we find it in old entry? */ + found = 0; + for (i = 0; bm[i].bv_val; i++) { + for (j = 0; bt[j].bv_val; j++) { + if (bm[i].bv_len != bt[j].bv_len) + continue; + if (memcmp(bm[i].bv_val, bt[j].bv_val, bt[j].bv_len) != 0) + continue; + + found++; + break; + } + } + + /* Did we find as many values as we had in old entry? */ + if (i != a->a_numvals || found != a->a_numvals) + continue; + + /* This is a nop, remove it */ + Debug(LDAP_DEBUG_TRACE, "removing nop on %s%s%s", + a->a_desc->ad_cname.bv_val, "", ""); + + nops_rm_mod(&op->orm_modlist, mc); + } + if (target_entry) { + op->o_bd = on->on_info->oi_origdb; + be_entry_release_r(op, target_entry); + op->o_bd = be; + } + + if ((m = op->orm_modlist) == NULL) { + op->o_bd->bd_info = (BackendInfo *)(on->on_info); + send_ldap_error(op, rs, LDAP_SUCCESS, ""); + return(rs->sr_err); + return (rs->sr_err); + } + + return SLAP_CB_CONTINUE; +} + +static slap_overinst nops_ovl; + +#if SLAPD_OVER_NOPS == SLAPD_MOD_DYNAMIC +static +#endif +int +nops_initialize( void ) { + nops_ovl.on_bi.bi_type = "nops"; + nops_ovl.on_bi.bi_op_modify = nops_modify; + return overlay_register( &nops_ovl ); +} + +#if SLAPD_OVER_NOPS == SLAPD_MOD_DYNAMIC +int init_module(int argc, char *argv[]) { + return nops_initialize(); +} +#endif + +#endif /* defined(SLAPD_OVER_NOPS) */ + diff --git a/contrib/slapd-modules/nops/slapo-nops.5 b/contrib/slapd-modules/nops/slapo-nops.5 new file mode 100644 index 0000000000..ac8f19d6c6 --- /dev/null +++ b/contrib/slapd-modules/nops/slapo-nops.5 @@ -0,0 +1,32 @@ +.TH SLAPO-NOPS 5 "RELEASEDATE" "OpenLDAP LDVERSION" +.\" Copyright 2008 Emmanuel Dreyfus +.\" Copying restrictions apply. See COPYRIGHT/LICENSE. +.\" $OpenLDAP$ +.SH NAME +slapo-nops \- Remove Null Operations Overlay to slapd +.SH SYNOPSIS +ETCDIR/slapd.conf +.SH DESCRIPTION +Some broken client tend to implement modifications as replace operations +where all attributes are replaced, most of the time by the same values +they had before. This can cause undesirable load on logs, ACL evaluation, +or replication trafic. + +This overlay detects idempotent replace operations and filter them out. +.SH CONFIGURATION +This overlay had no specific configuration. +.SH EXAMPLES +.LP +.RS +.nf +overlay nops +.RE +.SH FILES +.TP +ETCDIR/slapd.conf +default slapd configuration file +.SH SEE ALSO +.BR slapd.conf (5). +.SH ACKNOWLEDGEMENTS +This module was written in 2008 by Emmanuel Dreyfus. +.so ../Project -- 2.39.5