/* $NetBSD: subst.c,v 1.3 2021/08/14 16:14:58 christos Exp $ */
/* $OpenLDAP$ */
/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
*
* Copyright 2000-2021 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>.
*/
/* ACKNOWLEDGEMENT:
* This work was initially developed by Pierangelo Masarati for
* inclusion in OpenLDAP Software.
*/
#include <portable.h>
#include "rewrite-int.h"
/*
* Compiles a substitution pattern
*/
struct rewrite_subst *
rewrite_subst_compile(
struct rewrite_info *info,
const char *str
)
{
size_t subs_len;
struct berval *subs = NULL, *tmps;
struct rewrite_submatch *submatch = NULL, *tmpsm;
struct rewrite_subst *s = NULL;
char *result, *begin, *p;
int nsub = 0, l;
assert( info != NULL );
assert( str != NULL );
result = strdup( str );
if ( result == NULL ) {
return NULL;
}
/*
* Take care of substitution string
*/
for ( p = begin = result, subs_len = 0; p[ 0 ] != '\0'; p++ ) {
/*
* Keep only single escapes '%'
*/
if ( !IS_REWRITE_SUBMATCH_ESCAPE( p[ 0 ] ) ) {
continue;
}
if ( IS_REWRITE_SUBMATCH_ESCAPE( p[ 1 ] ) ) {
/* Pull &p[1] over p, including the trailing '\0' */
AC_MEMCPY((char *)p, &p[ 1 ], strlen( p ) );
continue;
}
tmps = ( struct berval * )realloc( subs,
sizeof( struct berval )*( nsub + 1 ) );
if ( tmps == NULL ) {
goto cleanup;
}
subs = tmps;
subs[ nsub ].bv_val = NULL;
tmpsm = ( struct rewrite_submatch * )realloc( submatch,
sizeof( struct rewrite_submatch )*( nsub + 1 ) );
if ( tmpsm == NULL ) {
goto cleanup;
}
submatch = tmpsm;
submatch[ nsub ].ls_map = NULL;
/*
* I think an `if l > 0' at runtime is better outside than
* inside a function call ...
*/
l = p - begin;
if ( l > 0 ) {
subs_len += l;
subs[ nsub ].bv_len = l;
subs[ nsub ].bv_val = malloc( l + 1 );
if ( subs[ nsub ].bv_val == NULL ) {
goto cleanup;
}
AC_MEMCPY( subs[ nsub ].bv_val, begin, l );
subs[ nsub ].bv_val[ l ] = '\0';
} else {
subs[ nsub ].bv_val = NULL;
subs[ nsub ].bv_len = 0;
}
/*
* Substitution pattern
*/
if ( isdigit( (unsigned char) p[ 1 ] ) ) {
int d = p[ 1 ] - '0';
/*
* Add a new value substitution scheme
*/
submatch[ nsub ].ls_submatch = d;
/*
* If there is no argument, use default
* (substitute substring as is)
*/
if ( p[ 2 ] != '{' ) {
submatch[ nsub ].ls_type =
REWRITE_SUBMATCH_ASIS;
submatch[ nsub ].ls_map = NULL;
begin = ++p + 1;
} else {
struct rewrite_map *map;
submatch[ nsub ].ls_type =
REWRITE_SUBMATCH_XMAP;
map = rewrite_xmap_parse( info,
p + 3, (const char **)&begin );
if ( map == NULL ) {
goto cleanup;
}
submatch[ nsub ].ls_map = map;
p = begin - 1;
}
/*
* Map with args ...
*/
} else if ( p[ 1 ] == '{' ) {
struct rewrite_map *map;
map = rewrite_map_parse( info, p + 2,
(const char **)&begin );
if ( map == NULL ) {
goto cleanup;
}
p = begin - 1;
/*
* Add a new value substitution scheme
*/
submatch[ nsub ].ls_type =
REWRITE_SUBMATCH_MAP_W_ARG;
submatch[ nsub ].ls_map = map;
/*
* Escape '%' ...
*/
} else if ( p[ 1 ] == '%' ) {
AC_MEMCPY( &p[ 1 ], &p[ 2 ], strlen( &p[ 1 ] ) );
continue;
} else {
goto cleanup;
}
nsub++;
}
/*
* Last part of string
*/
tmps = (struct berval * )realloc( subs, sizeof( struct berval )*( nsub + 1 ) );
if ( tmps == NULL ) {
/*
* XXX need to free the value subst stuff!
*/
free( subs );
goto cleanup;
}
subs = tmps;
l = p - begin;
if ( l > 0 ) {
subs_len += l;
subs[ nsub ].bv_len = l;
subs[ nsub ].bv_val = malloc( l + 1 );
if ( subs[ nsub ].bv_val == NULL ) {
goto cleanup;
}
AC_MEMCPY( subs[ nsub ].bv_val, begin, l );
subs[ nsub ].bv_val[ l ] = '\0';
} else {
subs[ nsub ].bv_val = NULL;
subs[ nsub ].bv_len = 0;
}
s = calloc( sizeof( struct rewrite_subst ), 1 );
if ( s == NULL ) {
goto cleanup;
}
s->lt_subs_len = subs_len;
s->lt_subs = subs;
s->lt_num_submatch = nsub;
s->lt_submatch = submatch;
subs = NULL;
submatch = NULL;
cleanup:;
if ( subs ) {
for ( l=0; l<nsub; l++ ) {
free( subs[nsub].bv_val );
}
free( subs );
}
if ( submatch ) {
for ( l=0; l<nsub; l++ ) {
free( submatch[nsub].ls_map );
}
free( submatch );
}
free( result );
return s;
}
/*
* Copies the match referred to by submatch and fetched in string by match.
* Helper for rewrite_rule_apply.
*/
static int
submatch_copy(
struct rewrite_submatch *submatch,
const char *string,
const regmatch_t *match,
struct berval *val
)
{
int c, l;
const char *s;
assert( submatch != NULL );
assert( submatch->ls_type == REWRITE_SUBMATCH_ASIS
|| submatch->ls_type == REWRITE_SUBMATCH_XMAP );
assert( string != NULL );
assert( match != NULL );
assert( val != NULL );
assert( val->bv_val == NULL );
c = submatch->ls_submatch;
s = string + match[ c ].rm_so;
l = match[ c ].rm_eo - match[ c ].rm_so;
val->bv_len = l;
val->bv_val = malloc( l + 1 );
if ( val->bv_val == NULL ) {
return REWRITE_ERR;
}
AC_MEMCPY( val->bv_val, s, l );
val->bv_val[ l ] = '\0';
return REWRITE_SUCCESS;
}
/*
* Substitutes a portion of rewritten string according to substitution
* pattern using submatches
*/
int
rewrite_subst_apply(
struct rewrite_info *info,
struct rewrite_op *op,
struct rewrite_subst *subst,
const char *string,
const regmatch_t *match,
struct berval *val
)
{
struct berval *submatch = NULL;
char *res = NULL;
int n = 0, l, cl;
int rc = REWRITE_REGEXEC_OK;
assert( info != NULL );
assert( op != NULL );
assert( subst != NULL );
assert( string != NULL );
assert( match != NULL );
assert( val != NULL );
assert( val->bv_val == NULL );
val->bv_val = NULL;
val->bv_len = 0;
/*
* Prepare room for submatch expansion
*/
if ( subst->lt_num_submatch > 0 ) {
submatch = calloc( sizeof( struct berval ),
subst->lt_num_submatch );
if ( submatch == NULL ) {
return REWRITE_REGEXEC_ERR;
}
}
/*
* Resolve submatches (simple subst, map expansion and so).
*/
for ( n = 0, l = 0; n < subst->lt_num_submatch; n++ ) {
struct berval key = { 0, NULL };
submatch[ n ].bv_val = NULL;
/*
* Get key
*/
switch ( subst->lt_submatch[ n ].ls_type ) {
case REWRITE_SUBMATCH_ASIS:
case REWRITE_SUBMATCH_XMAP:
rc = submatch_copy( &subst->lt_submatch[ n ],
string, match, &key );
if ( rc != REWRITE_SUCCESS ) {
rc = REWRITE_REGEXEC_ERR;
goto cleanup;
}
break;
case REWRITE_SUBMATCH_MAP_W_ARG:
switch ( subst->lt_submatch[ n ].ls_map->lm_type ) {
case REWRITE_MAP_GET_OP_VAR:
case REWRITE_MAP_GET_SESN_VAR:
case REWRITE_MAP_GET_PARAM:
rc = REWRITE_SUCCESS;
break;
default:
rc = rewrite_subst_apply( info, op,
subst->lt_submatch[ n ].ls_map->lm_subst,
string, match, &key);
}
if ( rc != REWRITE_SUCCESS ) {
goto cleanup;
}
break;
default:
Debug( LDAP_DEBUG_ANY, "Not Implemented\n" );
rc = REWRITE_ERR;
break;
}
if ( rc != REWRITE_SUCCESS ) {
rc = REWRITE_REGEXEC_ERR;
goto cleanup;
}
/*
* Resolve key
*/
switch ( subst->lt_submatch[ n ].ls_type ) {
case REWRITE_SUBMATCH_ASIS:
submatch[ n ] = key;
rc = REWRITE_SUCCESS;
break;
case REWRITE_SUBMATCH_XMAP:
rc = rewrite_xmap_apply( info, op,
subst->lt_submatch[ n ].ls_map,
&key, &submatch[ n ] );
free( key.bv_val );
key.bv_val = NULL;
break;
case REWRITE_SUBMATCH_MAP_W_ARG:
rc = rewrite_map_apply( info, op,
subst->lt_submatch[ n ].ls_map,
&key, &submatch[ n ] );
free( key.bv_val );
key.bv_val = NULL;
break;
default:
/*
* When implemented, this might return the
* exit status of a rewrite context,
* which may include a stop, or an
* unwilling to perform
*/
rc = REWRITE_ERR;
break;
}
if ( rc != REWRITE_SUCCESS ) {
rc = REWRITE_REGEXEC_ERR;
goto cleanup;
}
/*
* Increment the length of the resulting string
*/
l += submatch[ n ].bv_len;
}
/*
* Alloc result buffer
*/
l += subst->lt_subs_len;
res = malloc( l + 1 );
if ( res == NULL ) {
rc = REWRITE_REGEXEC_ERR;
goto cleanup;
}
/*
* Apply submatches (possibly resolved thru maps)
*/
for ( n = 0, cl = 0; n < subst->lt_num_submatch; n++ ) {
if ( subst->lt_subs[ n ].bv_val != NULL ) {
AC_MEMCPY( res + cl, subst->lt_subs[ n ].bv_val,
subst->lt_subs[ n ].bv_len );
cl += subst->lt_subs[ n ].bv_len;
}
AC_MEMCPY( res + cl, submatch[ n ].bv_val,
submatch[ n ].bv_len );
cl += submatch[ n ].bv_len;
}
if ( subst->lt_subs[ n ].bv_val != NULL ) {
AC_MEMCPY( res + cl, subst->lt_subs[ n ].bv_val,
subst->lt_subs[ n ].bv_len );
cl += subst->lt_subs[ n ].bv_len;
}
res[ cl ] = '\0';
val->bv_val = res;
val->bv_len = l;
cleanup:;
if ( submatch ) {
for ( ; --n >= 0; ) {
if ( submatch[ n ].bv_val ) {
free( submatch[ n ].bv_val );
}
}
free( submatch );
}
return rc;
}
/*
* frees data
*/
int
rewrite_subst_destroy(
struct rewrite_subst **psubst
)
{
int n;
struct rewrite_subst *subst;
assert( psubst != NULL );
assert( *psubst != NULL );
subst = *psubst;
for ( n = 0; n < subst->lt_num_submatch; n++ ) {
if ( subst->lt_subs[ n ].bv_val ) {
free( subst->lt_subs[ n ].bv_val );
subst->lt_subs[ n ].bv_val = NULL;
}
switch ( subst->lt_submatch[ n ].ls_type ) {
case REWRITE_SUBMATCH_ASIS:
break;
case REWRITE_SUBMATCH_XMAP:
rewrite_xmap_destroy( &subst->lt_submatch[ n ].ls_map );
break;
case REWRITE_SUBMATCH_MAP_W_ARG:
rewrite_map_destroy( &subst->lt_submatch[ n ].ls_map );
break;
default:
break;
}
}
free( subst->lt_submatch );
subst->lt_submatch = NULL;
/* last one */
if ( subst->lt_subs[ n ].bv_val ) {
free( subst->lt_subs[ n ].bv_val );
subst->lt_subs[ n ].bv_val = NULL;
}
free( subst->lt_subs );
subst->lt_subs = NULL;
free( subst );
*psubst = NULL;
return 0;
}