compile.c

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/*
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */
 
/**
 * $Id: cce0ec2443cc2018bb5690ca761259f60782d9e5 $
 *
 * @file unlang/compile.c
 * @brief Functions to convert configuration sections into unlang structures.
 *
 * @copyright 2006-2016 The FreeRADIUS server project
 */
RCSID("$Id: cce0ec2443cc2018bb5690ca761259f60782d9e5 $")
 
#include <freeradius-devel/protocol/freeradius/freeradius.internal.h>
 
#include <freeradius-devel/server/virtual_servers.h>
 
#include <freeradius-devel/server/cf_file.h>
#include <freeradius-devel/server/map_proc.h>
#include <freeradius-devel/server/modpriv.h>
 
 
#include <freeradius-devel/unlang/xlat_priv.h>
 
#include "call_priv.h"
#include "caller_priv.h"
#include "condition_priv.h"
#include "foreach_priv.h"
#include "load_balance_priv.h"
#include "map_priv.h"
#include "module_priv.h"
#include "parallel_priv.h"
#include "subrequest_priv.h"
#include "switch_priv.h"
#include "edit_priv.h"
#include "timeout_priv.h"
#include "limit_priv.h"
#include "transaction_priv.h"
#include "try_priv.h"
#include "mod_action.h"
 
extern uint64_t unlang_number;
 
/*
 *      Until we know how many instructions there are, we can't
 *      allocate an array.  So we have to put the instructions into an
 *      RB tree.
 */
extern fr_rb_tree_t *unlang_instruction_tree;
fr_rb_tree_t *unlang_instruction_tree = NULL;
 
/* Here's where we recognize all of our keywords: first the rcodes, then the
 * actions */
fr_table_num_sorted_t const mod_rcode_table[] = {
        { L("..."),             RLM_MODULE_NOT_SET      },
        { L("disallow"),        RLM_MODULE_DISALLOW     },
        { L("fail"),            RLM_MODULE_FAIL         },
        { L("handled"),         RLM_MODULE_HANDLED      },
        { L("invalid"),         RLM_MODULE_INVALID      },
        { L("noop"),            RLM_MODULE_NOOP         },
        { L("notfound"),        RLM_MODULE_NOTFOUND     },
        { L("ok"),              RLM_MODULE_OK           },
        { L("reject"),          RLM_MODULE_REJECT       },
        { L("timeout"),         RLM_MODULE_TIMEOUT      },
        { L("updated"),         RLM_MODULE_UPDATED      }
};
size_t mod_rcode_table_len = NUM_ELEMENTS(mod_rcode_table);
 
#define UPDATE_CTX2 unlang_compile_ctx_copy(&unlang_ctx2, unlang_ctx)
 
 
static char const unlang_spaces[] = "                                                                                                                                                                                                                                                                ";
 
bool pass2_fixup_tmpl(UNUSED TALLOC_CTX *ctx, tmpl_t **vpt_p, CONF_ITEM const *ci, fr_dict_t const *dict)
{
        tmpl_t *vpt = *vpt_p;
 
        TMPL_VERIFY(vpt);
 
        /*
         *      We may now know the correct dictionary
         *      where we didn't before...
         */
        if (!vpt->rules.attr.dict_def) tmpl_set_dict_def(vpt, dict);
 
        /*
         *      Fixup any other tmpl types
         */
        if (tmpl_resolve(vpt, &(tmpl_res_rules_t){ .dict_def = dict, .force_dict_def = (dict != NULL)}) < 0) {
                cf_log_perr(ci, NULL);
                return false;
        }
 
        return true;
}
 
/** Fixup ONE map (recursively)
 *
 *  This function resolves most things.  Most notable it CAN leave the
 *  RHS unresolved, for use in `map` sections.
 */
bool pass2_fixup_map(map_t *map, tmpl_rules_t const *rules, fr_dict_attr_t const *parent)
{
        RULES_VERIFY(rules);
 
        if (tmpl_is_data_unresolved(map->lhs)) {
                if (!pass2_fixup_tmpl(map, &map->lhs, map->ci, rules->attr.dict_def)) {
                        return false;
                }
        }
 
        /*
         *      Enforce parent-child relationships in nested maps.
         */
        if (parent) {
                if ((map->op != T_OP_EQ) && (!map->parent || (map->parent->op != T_OP_SUB_EQ))) {
                        cf_log_err(map->ci, "Invalid operator \"%s\" in nested map section.  "
                                   "Only '=' is allowed",
                                   fr_table_str_by_value(fr_tokens_table, map->op, "<INVALID>"));
                        return false;
                }
        }
 
        if (map->rhs) {
                if (tmpl_is_data_unresolved(map->rhs)) {
                        fr_assert(!tmpl_is_regex_xlat_unresolved(map->rhs));
 
                        if (!pass2_fixup_tmpl(map, &map->rhs, map->ci, rules->attr.dict_def)) {
                                return false;
                        }
                }
        }
 
        /*
         *      Sanity check sublists.
         */
        if (!map_list_empty(&map->child)) {
                fr_dict_attr_t const *da;
                map_t *child;
 
                if (!tmpl_is_attr(map->lhs)) {
                        cf_log_err(map->ci, "Sublists can only be assigned to a known attribute");
                        return false;
                }
 
                da = tmpl_attr_tail_da(map->lhs);
 
                /*
                 *      Resolve all children.
                 */
                for (child = map_list_next(&map->child, NULL);
                     child != NULL;
                     child = map_list_next(&map->child, child)) {
                        if (!pass2_fixup_map(child, rules, da)) {
                                return false;
                        }
                }
        }
 
        return true;
}
 
/*
 *      Do all kinds of fixups and checks for update sections.
 */
bool pass2_fixup_update(unlang_group_t *g, tmpl_rules_t const *rules)
{
        unlang_map_t    *gext = unlang_group_to_map(g);
        map_t           *map = NULL;
 
        RULES_VERIFY(rules);
 
        while ((map = map_list_next(&gext->map, map))) {
                /*
                 *      Mostly fixup the map, but maybe leave the RHS
                 *      unresolved.
                 */
                if (!pass2_fixup_map(map, rules, NULL)) return false;
 
                /*
                 *      Check allowed operators, and ensure that the
                 *      RHS is resolved.
                 */
                if (cf_item_is_pair(map->ci) && (unlang_fixup_update(map, NULL) < 0)) return false;
        }
 
        return true;
}
 
/*
 *      Compile the RHS of map sections to xlat_exp_t
 */
bool pass2_fixup_map_rhs(unlang_group_t *g, tmpl_rules_t const *rules)
{
        unlang_map_t    *gext = unlang_group_to_map(g);
        map_t           *map = NULL;
 
        RULES_VERIFY(rules);
 
        /*
         *      Do most fixups on the maps.  Leaving the RHS as
         *      unresolved, so that the `map` function can interpret
         *      the RHS as a reference to a json string, SQL column
         *      name, etc.
         */
        while ((map = map_list_next(&gext->map, map))) {
                if (!pass2_fixup_map(map, rules, NULL)) return false;
        }
 
        /*
         *      Map sections don't need a VPT.
         */
        if (!gext->vpt) return true;
 
        if (map_list_num_elements(&gext->map) == 0) return true;
 
        return pass2_fixup_tmpl(map_list_head(&gext->map)->ci, &gext->vpt,
                                cf_section_to_item(g->cs), rules->attr.dict_def);
}
 
static void unlang_dump(unlang_t *c, int depth)
{
        unlang_group_t *g;
        map_t *map;
        char buffer[1024];
 
        switch (c->type) {
        case UNLANG_TYPE_NULL:
        case UNLANG_TYPE_CHILD_REQUEST:
        case UNLANG_TYPE_MAX:
                fr_assert(0);
                break;
 
        case UNLANG_TYPE_FUNCTION:
                DEBUG("%.*s%s", depth, unlang_spaces, c->debug_name);
                break;
 
        case UNLANG_TYPE_MODULE:
        {
                unlang_module_t *m = unlang_generic_to_module(c);
 
                DEBUG("%.*s%s", depth, unlang_spaces, m->mmc.mi->name);
        }
        break;
 
        case UNLANG_TYPE_MAP:
        {
                unlang_map_t *gext;
 
                DEBUG("%.*s%s {", depth, unlang_spaces, c->debug_name);
 
                g = unlang_generic_to_group(c);
                gext = unlang_group_to_map(g);
                map = NULL;
                while ((map = map_list_next(&gext->map, map))) {
                        map_print(&FR_SBUFF_OUT(buffer, sizeof(buffer)), map);
                        DEBUG("%.*s%s", depth + 1, unlang_spaces, buffer);
                }
 
                DEBUG("%.*s}", depth, unlang_spaces);
        }
        break;
 
        case UNLANG_TYPE_EDIT:
        {
                unlang_edit_t *edit;
 
                DEBUG("%.*s%s {", depth, unlang_spaces, c->debug_name);
 
                edit = unlang_generic_to_edit(c);
                map = NULL;
                while ((map = map_list_next(&edit->maps, map))) {
                        if (!map->rhs) continue; /* @todo - fixme */
 
                        map_print(&FR_SBUFF_OUT(buffer, sizeof(buffer)), map);
                        DEBUG("%.*s%s", depth + 1, unlang_spaces, buffer);
                }
 
                DEBUG("%.*s}", depth, unlang_spaces);
        }
        break;
 
        case UNLANG_TYPE_CALL:
        case UNLANG_TYPE_CALLER:
        case UNLANG_TYPE_CASE:
        case UNLANG_TYPE_FOREACH:
        case UNLANG_TYPE_FINALLY:
        case UNLANG_TYPE_ELSE:
        case UNLANG_TYPE_ELSIF:
        case UNLANG_TYPE_GROUP:
        case UNLANG_TYPE_IF:
        case UNLANG_TYPE_LOAD_BALANCE:
        case UNLANG_TYPE_PARALLEL:
        case UNLANG_TYPE_POLICY:
        case UNLANG_TYPE_REDUNDANT:
        case UNLANG_TYPE_REDUNDANT_LOAD_BALANCE:
        case UNLANG_TYPE_SUBREQUEST:
        case UNLANG_TYPE_SWITCH:
        case UNLANG_TYPE_TIMEOUT:
        case UNLANG_TYPE_LIMIT:
        case UNLANG_TYPE_TRANSACTION:
        case UNLANG_TYPE_TRY:
        case UNLANG_TYPE_CATCH: /* @todo - print out things we catch, too */
                g = unlang_generic_to_group(c);
 
                DEBUG("%.*s%s {", depth, unlang_spaces, c->debug_name);
                unlang_list_foreach(&g->children, child) {
                        unlang_dump(child, depth + 1);
                }
                DEBUG("%.*s}", depth, unlang_spaces);
                break;
 
        case UNLANG_TYPE_BREAK:
        case UNLANG_TYPE_CONTINUE:
        case UNLANG_TYPE_DETACH:
        case UNLANG_TYPE_RETURN:
        case UNLANG_TYPE_TMPL:
        case UNLANG_TYPE_XLAT:
                DEBUG("%.*s%s", depth, unlang_spaces, c->debug_name);
                break;
        }
}
 
 
/** Validate and fixup a map that's part of an update section.
 *
 * @param map to validate.
 * @param ctx data to pass to fixup function (currently unused).
 * @return
 *      - 0 if valid.
 *      - -1 not valid.
 */
int unlang_fixup_update(map_t *map, void *ctx)
{
        CONF_PAIR *cp = cf_item_to_pair(map->ci);
 
        if (!ctx) {
                /*
                 *      Fixup RHS attribute references to change NUM_UNSPEC to NUM_ALL.
                 *
                 *      RHS may be NULL for T_OP_CMP_FALSE.
                 */
                if (map->rhs) {
                        switch (map->rhs->type) {
                        case TMPL_TYPE_ATTR:
                                if (!tmpl_is_list(map->rhs)) tmpl_attr_rewrite_leaf_num(map->rhs, NUM_ALL);
                                break;
 
                        default:
                                break;
                        }
                }
        }
 
        /*
         *      Lots of sanity checks for insane people...
         */
 
        /*
         *      Depending on the attribute type, some operators are disallowed.
         */
        if (tmpl_is_attr(map->lhs)) {
                /*
                 *      What exactly were you expecting to happen here?
                 */
                if (tmpl_attr_tail_da_is_leaf(map->lhs) &&
                    map->rhs && tmpl_is_list(map->rhs)) {
                        cf_log_err(map->ci, "Can't copy list into an attribute");
                        return -1;
                }
 
                if (!fr_assignment_op[map->op] && !fr_comparison_op[map->op] && !fr_binary_op[map->op]) {
                        cf_log_err(map->ci, "Invalid operator \"%s\" in update section.  "
                                   "Only assignment or filter operators are allowed",
                                   fr_table_str_by_value(fr_tokens_table, map->op, "<INVALID>"));
                        return -1;
                }
 
                if (fr_comparison_op[map->op] && (map->op != T_OP_CMP_FALSE)) {
                        cf_log_warn(cp, "Please use the 'filter' keyword for attribute filtering");
                }
        }
 
        /*
         *      If the map has a unary operator there's no further
         *      processing we need to, as RHS is unused.
         */
        if (map->op == T_OP_CMP_FALSE) return 0;
 
        if (unlikely(!map->rhs)) {
                cf_log_err(map->ci, "Missing rhs");
                return -1;
        }
 
        if (!tmpl_is_data_unresolved(map->rhs)) return 0;
 
        /*
         *      If LHS is an attribute, and RHS is a literal, we can
         *      preparse the information into a TMPL_TYPE_DATA.
         *
         *      Unless it's a unary operator in which case we
         *      ignore map->rhs.
         */
        if (tmpl_is_attr(map->lhs) && tmpl_is_data_unresolved(map->rhs)) {
                fr_type_t type = tmpl_attr_tail_da(map->lhs)->type;
 
                /*
                 *      @todo - allow passing octets to
                 *      FR_TYPE_STRUCT, which can then decode them as
                 *      data?  That would be rather powerful.
                 */
                if (fr_type_is_structural(type)) type = FR_TYPE_STRING;
 
                /*
                 *      It's a literal string, just copy it.
                 *      Don't escape anything.
                 */
                if (tmpl_cast_in_place(map->rhs, type, tmpl_attr_tail_da(map->lhs)) < 0) {
                        cf_log_perr(map->ci, "Cannot convert RHS value (%s) to LHS attribute type (%s)",
                                    fr_type_to_str(FR_TYPE_STRING),
                                    fr_type_to_str(tmpl_attr_tail_da(map->lhs)->type));
                        return -1;
                }
 
                return 0;
        } /* else we can't precompile the data */
 
        if (!tmpl_is_xlat(map->lhs)) {
                fr_assert(0);
                cf_log_err(map->ci, "Cannot determine what update action to perform");
                return -1;
        }
 
        return 0;
}
 
 
unlang_group_t *unlang_group_allocate(unlang_t *parent, CONF_SECTION *cs, unlang_type_t type)
{
        unlang_group_t  *g;
        unlang_t        *c;
        TALLOC_CTX      *ctx;
        unlang_op_t const *op = &unlang_ops[type];
 
        ctx = parent;
        if (!ctx) ctx = cs;
 
        fr_assert(op->unlang_size > 0);
 
        /*
         *      All the groups have a common header
         */
        g = (unlang_group_t *)_talloc_zero_pooled_object(ctx, op->unlang_size, op->unlang_name,
                                                         op->pool_headers, op->pool_len);
        if (!g) return NULL;
 
        g->cs = cs;
 
        c = unlang_group_to_generic(g);
        c->ci = CF_TO_ITEM(cs);
 
        unlang_group_type_init(c, parent, type);
 
        return g;
}
 
/**  Update a compiled unlang_t with the default actions.
 *
 *  Don't over-ride any actions which have been set.
 */
static void compile_set_default_actions(unlang_t *c, unlang_compile_ctx_t *unlang_ctx)
{
        int i;
 
        /*
         *      Note that we do NOT copy over the default retries, as
         *      that would result in every subsection doing it's own
         *      retries.  That is not what we want.  Instead, we want
         *      the retries to apply only to the _current_ section.
         */
 
        /*
         *      Set the default actions if they haven't already been
         *      set.
         */
        for (i = 0; i < RLM_MODULE_NUMCODES; i++) {
                if (!c->actions.actions[i]) {
                        c->actions.actions[i] = unlang_ctx->actions.actions[i];
                }
        }
}
 
#define T(_x) [T_OP_ ## _x] = true
 
static const bool edit_list_sub_op[T_TOKEN_LAST] = {
        T(NE),
        T(GE),
        T(GT),
        T(LE),
        T(LT),
        T(CMP_EQ),
};
 
/** Validate and fixup a map that's part of an edit section.
 *
 * @param map to validate.
 * @param ctx data to pass to fixup function (currently unused).
 * @return 0 if valid else -1.
 *
 *  @todo - this is only called for CONF_PAIR maps, not for
 *  CONF_SECTION.  So when we parse nested maps, there's no validation
 *  done of the CONF_SECTION.  In order to fix this, we need to have
 *  map_afrom_cs() call the validation function for the CONF_SECTION
 *  *before* recursing.
 */
static int unlang_fixup_edit(map_t *map, void *ctx)
{
        CONF_PAIR *cp = cf_item_to_pair(map->ci);
        fr_dict_attr_t const *da;
        fr_dict_attr_t const *parent = NULL;
        map_t           *parent_map = ctx;
 
        fr_assert(parent_map);
#ifdef STATIC_ANALYZER
        if (!parent_map) return -1;
#endif
 
        fr_assert(tmpl_is_attr(parent_map->lhs));
 
        if (parent_map->op == T_OP_SUB_EQ) {
                if (!edit_list_sub_op[map->op]) {
                        cf_log_err(cp, "Invalid operator '%s' for right-hand side list.  It must be a comparison operator", fr_tokens[map->op]);
                        return -1;
                }
 
        } else if (map->op != T_OP_EQ) {
                cf_log_err(cp, "Invalid operator '%s' for right-hand side list.  It must be '='", fr_tokens[map->op]);
                return -1;
        }
 
        /*
         *      map_afrom_cs() will build its tree recursively, and call us for each child map.
         */
        if (map->parent && (map->parent != parent_map)) parent_map = map->parent;
 
        parent = tmpl_attr_tail_da(parent_map->lhs);
 
        switch (map->lhs->type) {
        case TMPL_TYPE_ATTR:
                da = tmpl_attr_tail_da(map->lhs);
                if (!da->flags.internal && parent && (parent->type != FR_TYPE_GROUP) &&
                    (da->parent != parent)) {
                        /* FIXME - Broken check, doesn't work for key attributes */
                        cf_log_err(cp, "Invalid location for %s - it is not a child of %s",
                                   da->name, parent->name);
                        return -1;
                }
                break;
 
        case TMPL_TYPE_XLAT_UNRESOLVED:
        case TMPL_TYPE_XLAT:
                break;
 
        default:
                cf_log_err(map->ci, "Left side of map must be an attribute "
                           "or an xlat (that expands to an attribute), not a %s",
                           tmpl_type_to_str(map->lhs->type));
                return -1;
        }
 
        fr_assert(map->rhs);
 
        switch (map->rhs->type) {
        case TMPL_TYPE_DATA_UNRESOLVED:
        case TMPL_TYPE_XLAT_UNRESOLVED:
        case TMPL_TYPE_XLAT:
        case TMPL_TYPE_DATA:
        case TMPL_TYPE_ATTR:
        case TMPL_TYPE_EXEC:
                break;
 
        default:
                cf_log_err(map->ci, "Right side of map must be an attribute, literal, xlat or exec, got type %s",
                           tmpl_type_to_str(map->rhs->type));
                return -1;
        }
 
        return 0;
}
 
/** Compile one edit section.
 */
static unlang_t *compile_edit_section(unlang_t *parent, unlang_compile_ctx_t *unlang_ctx, CONF_SECTION *cs)
{
        unlang_edit_t           *edit;
        unlang_t                *c, *out = UNLANG_IGNORE;
        map_t                   *map;
        char const              *name;
        fr_token_t              op;
        ssize_t                 slen;
        fr_dict_attr_t const    *parent_da;
        int                     num;
 
        tmpl_rules_t            t_rules;
 
        name = cf_section_name2(cs);
        if (name) {
                cf_log_err(cs, "Unexpected name2 '%s' for editing list %s ", name, cf_section_name1(cs));
                return NULL;
        }
 
        op = cf_section_name2_quote(cs);
        if ((op == T_INVALID) || !fr_list_assignment_op[op]) {
                cf_log_err(cs, "Invalid operator '%s' for editing list %s.", fr_tokens[op], cf_section_name1(cs));
                return NULL;
        }
 
        if ((op == T_OP_CMP_TRUE) || (op == T_OP_CMP_FALSE)) {
                cf_log_err(cs, "Invalid operator \"%s\".",
                           fr_table_str_by_value(fr_tokens_table, op, "<INVALID>"));
                return NULL;
        }
 
        /*
         *      We allow unknown attributes here.
         */
        t_rules = *(unlang_ctx->rules);
        t_rules.attr.allow_unknown = true;
        RULES_VERIFY(&t_rules);
 
        edit = talloc_zero(parent, unlang_edit_t);
        if (!edit) return NULL;
 
        c = out = unlang_edit_to_generic(edit);
        unlang_type_init(c, parent, UNLANG_TYPE_EDIT);
        c->name = cf_section_name1(cs);
        c->debug_name = c->name;
        c->ci = CF_TO_ITEM(cs);
 
        map_list_init(&edit->maps);
 
        /*
         *      Allocate the map and initialize it.
         */
        MEM(map = talloc_zero(edit, map_t));
        map->op = op;
        map->ci = cf_section_to_item(cs);
        map_list_init(&map->child);
 
        name = cf_section_name1(cs);
 
        slen = tmpl_afrom_attr_str(map, NULL, &map->lhs, name, &t_rules);
        if (slen <= 0) {
                cf_log_err(cs, "Failed parsing list reference %s - %s", name, fr_strerror());
        fail:
                talloc_free(edit);
                return NULL;
        }
 
        /*
         *      Can't assign to [*] or [#]
         */
        num = tmpl_attr_tail_num(map->lhs);
        if ((num == NUM_ALL) || (num == NUM_COUNT)) {
                cf_log_err(cs, "Invalid array reference in %s", name);
                goto fail;
        }
 
        /*
         *      If the DA isn't structural, then it can't have children.
         */
        parent_da = tmpl_attr_tail_da(map->lhs);
        if (fr_type_is_structural(parent_da->type)) {
                map_t *child;
 
                /*
                 *      Reset the namespace to be this attribute.  The tmpl tokenizer will take care of
                 *      figuring out if this is a group, TLV, dictionary switch, etc.
                 */
                t_rules.attr.namespace = parent_da;
 
                if (map_afrom_cs_edit(map, &map->child, cs, &t_rules, &t_rules, unlang_fixup_edit, map, 256) < 0) {
                        goto fail;
                }
 
                /*
                 *      As a set of fixups... we can't do array references in -=
                 */
                if (map->op == T_OP_SUB_EQ) {
                        for (child = map_list_head(&map->child); child != NULL; child = map_list_next(&map->child, child)) {
                                if (!tmpl_is_attr(child->lhs)) continue;
 
                                if (tmpl_attr_tail_num(child->lhs) != NUM_UNSPEC) {
                                        cf_log_err(child->ci, "Cannot use array references and values when deleting from a list");
                                        goto fail;
                                }
 
                                /*
                                 *      The edit code doesn't do this correctly, so we just forbid it.
                                 */
                                if ((tmpl_attr_num_elements(child->lhs) - tmpl_attr_num_elements(map->lhs)) > 1) {
                                        cf_log_err(child->ci, "List deletion must operate directly on the final child");
                                        goto fail;
                                }
 
                                /*
                                 *      We don't do list comparisons either.
                                 */
                                if (fr_type_is_structural(tmpl_attr_tail_da(child->lhs)->type)) {
                                        cf_log_err(child->ci, "List deletion cannot operate on lists");
                                        goto fail;
                                }
                        }
                }
        } else {
                /*
                 *      foo := { a, b, c }
                 */
                if (map_list_afrom_cs(map, &map->child, cs, &t_rules, NULL, NULL, 256) < 0) {
                        goto fail;
                }
 
                if ((map->op != T_OP_SET) && !map_list_num_elements(&map->child)) {
                        cf_log_err(cs, "Cannot use operator '%s' for assigning empty list to '%s' data type.",
                                   fr_tokens[map->op], fr_type_to_str(parent_da->type));
                        goto fail;
                }
        }
        /*
         *      Do basic sanity checks and resolving.
         */
        if (!pass2_fixup_map(map, unlang_ctx->rules, NULL)) goto fail;
 
        /*
         *      Check operators, and ensure that the RHS has been
         *      resolved.
         */
//      if (unlang_fixup_update(map, NULL) < 0) goto fail;
 
        map_list_insert_tail(&edit->maps, map);
 
        return out;
}
 
/** Compile one edit pair
 *
 */
static unlang_t *compile_edit_pair(unlang_t *parent, unlang_compile_ctx_t *unlang_ctx, CONF_PAIR *cp)
{
        unlang_edit_t           *edit;
        unlang_t                *c = NULL, *out = UNLANG_IGNORE;
        map_t                   *map;
        int                     num;
 
        tmpl_rules_t            t_rules;
        fr_token_t              op;
 
        /*
         *      We allow unknown attributes here.
         */
        t_rules = *(unlang_ctx->rules);
        t_rules.attr.allow_unknown = true;
        fr_assert(t_rules.attr.ci == cf_pair_to_item(cp));
        RULES_VERIFY(&t_rules);
 
        edit = talloc_zero(parent, unlang_edit_t);
        if (!edit) return NULL;
 
        c = out = unlang_edit_to_generic(edit);
        unlang_type_init(c, parent, UNLANG_TYPE_EDIT);
        c->name = cf_pair_attr(cp);
        c->debug_name = c->name;
        c->ci = CF_TO_ITEM(cp);
 
        map_list_init(&edit->maps);
 
        op = cf_pair_operator(cp);
        if ((op == T_OP_CMP_TRUE) || (op == T_OP_CMP_FALSE)) {
                cf_log_err(cp, "Invalid operator \"%s\".",
                           fr_table_str_by_value(fr_tokens_table, op, "<INVALID>"));
        fail:
                talloc_free(edit);
                return NULL;
        }
 
        /*
         *      Convert this particular map.
         */
        if (map_afrom_cp(edit, &map, map_list_tail(&edit->maps), cp, &t_rules, NULL, true) < 0) {
                goto fail;
        }
 
        /*
         *      @todo - we still want to do fixups on the RHS?
         */
        if (tmpl_is_attr(map->lhs)) {
                /*
                 *      Can't assign to [*] or [#]
                 */
                num = tmpl_attr_tail_num(map->lhs);
                if ((num == NUM_ALL) || (num == NUM_COUNT)) {
                        cf_log_err(cp, "Invalid array reference in %s", map->lhs->name);
                        goto fail;
                }
 
                if ((map->op == T_OP_SUB_EQ) && fr_type_is_structural(tmpl_attr_tail_da(map->lhs)->type) &&
                    tmpl_is_attr(map->rhs) && tmpl_attr_tail_da(map->rhs)->flags.local) {
                        cf_log_err(cp, "Cannot delete local variable %s", map->rhs->name);
                        goto fail;
                }
        }
 
        /*
         *      Do basic sanity checks and resolving.
         */
        if (!pass2_fixup_map(map, unlang_ctx->rules, NULL)) goto fail;
 
        /*
         *      Check operators, and ensure that the RHS has been
         *      resolved.
         */
        if (unlang_fixup_update(map, c) < 0) goto fail;
 
        map_list_insert_tail(&edit->maps, map);
 
        return out;
}
 
/** Compile a variable definition.
 *
 *  Definitions which are adjacent to one another are automatically merged
 *  into one larger variable definition.
 */
static int compile_variable(unlang_t *parent, unlang_compile_ctx_t *unlang_ctx, CONF_PAIR *cp, tmpl_rules_t *t_rules)
{
        unlang_variable_t *var;
        fr_type_t       type;
        char const      *attr, *value;
        unlang_group_t  *group;
 
        fr_assert(debug_braces(parent->type));
 
        /*
         *      Enforce locations for local variables.
         */
        switch (parent->type) {
        case UNLANG_TYPE_CASE:
        case UNLANG_TYPE_ELSE:
        case UNLANG_TYPE_ELSIF:
        case UNLANG_TYPE_FOREACH:
        case UNLANG_TYPE_GROUP:
        case UNLANG_TYPE_IF:
        case UNLANG_TYPE_TIMEOUT:
        case UNLANG_TYPE_LIMIT:
        case UNLANG_TYPE_POLICY:
        case UNLANG_TYPE_REDUNDANT:
        case UNLANG_TYPE_SUBREQUEST:
        case UNLANG_TYPE_LOAD_BALANCE:
        case UNLANG_TYPE_REDUNDANT_LOAD_BALANCE:
                break;
 
        default:
                cf_log_err(cp, "Local variables cannot be used here");
                return -1;
        }
 
        /*
         *      The variables exist in the parent block.
         */
        group = unlang_generic_to_group(parent);
        if (group->variables) {
                var = group->variables;
 
        } else {
                group->variables = var = talloc_zero(parent, unlang_variable_t);
                if (!var) return -1;
 
                var->dict = fr_dict_protocol_alloc(unlang_ctx->rules->attr.dict_def);
                if (!var->dict) {
                        group->variables = NULL;
                        talloc_free(var);
                        return -1;
                }
                var->root = fr_dict_root(var->dict);
 
                var->max_attr = 1;
 
                /*
                 *      Initialize the new rules, and point them to the parent rules.
                 *
                 *      Then replace the parse rules with our rules, and our dictionary.
                 */
                *t_rules = *unlang_ctx->rules;
                t_rules->parent = unlang_ctx->rules;
 
                t_rules->attr.dict_def = var->dict;
                t_rules->attr.namespace = NULL;
 
                unlang_ctx->rules = t_rules;
        }
 
        attr = cf_pair_attr(cp);        /* data type */
        value = cf_pair_value(cp);      /* variable name */
 
        type = fr_table_value_by_str(fr_type_table, attr, FR_TYPE_NULL);
        if (type == FR_TYPE_NULL) {
invalid_type:
                cf_log_err(cp, "Invalid data type '%s'", attr);
                return -1;
        }
 
        /*
         *      Leaf and group are OK.  TLV, Vendor, Struct, VSA, etc. are not.
         */
        if (!(fr_type_is_leaf(type) || (type == FR_TYPE_GROUP))) goto invalid_type;
 
        return unlang_define_local_variable(cf_pair_to_item(cp), var, t_rules, type, value, NULL);
}
 
/*
 *      Compile action && rcode for later use.
 */
static bool compile_action_pair(unlang_mod_actions_t *actions, CONF_PAIR *cp)
{
        int action;
        char const *attr, *value;
 
        attr = cf_pair_attr(cp);
        value = cf_pair_value(cp);
        if (!value) return true;
 
        if (!strcasecmp(value, "return"))
                action = MOD_ACTION_RETURN;
 
        else if (!strcasecmp(value, "break"))
                action = MOD_ACTION_RETURN;
 
        else if (!strcasecmp(value, "reject"))
                action = MOD_ACTION_REJECT;
 
        else if (!strcasecmp(value, "retry"))
                action = MOD_ACTION_RETRY;
 
        else if (strspn(value, "0123456789") == strlen(value)) {
                if (strlen(value) > 2) {
                invalid_action:
                        cf_log_err(cp, "Priorities MUST be between 1 and 64.");
                        return false;
                }
 
                action = MOD_PRIORITY(atoi(value));
 
                if (!MOD_ACTION_VALID_SET(action)) goto invalid_action;
 
        } else {
                cf_log_err(cp, "Unknown action '%s'.\n",
                           value);
                return false;
        }
 
        if (strcasecmp(attr, "default") != 0) {
                int rcode;
 
                rcode = fr_table_value_by_str(mod_rcode_table, attr, -1);
                if (rcode < 0) {
                        cf_log_err(cp,
                                   "Unknown module rcode '%s'.",
                                   attr);
                        return false;
                }
                actions->actions[rcode] = action;
 
        } else {                /* set all unset values to the default */
                int i;
 
                for (i = 0; i < RLM_MODULE_NUMCODES; i++) {
                        if (!actions->actions[i]) actions->actions[i] = action;
                }
        }
 
        return true;
}
 
static bool compile_retry_section(unlang_mod_actions_t *actions, CONF_ITEM *ci)
{
        CONF_ITEM *csi;
        CONF_SECTION *cs;
 
        cs = cf_item_to_section(ci);
        for (csi=cf_item_next(cs, NULL);
             csi != NULL;
             csi=cf_item_next(cs, csi)) {
                CONF_PAIR *cp;
                char const *name, *value;
 
                if (cf_item_is_section(csi)) {
                        cf_log_err(csi, "Invalid subsection in 'retry' configuration.");
                        return false;
                }
 
                if (!cf_item_is_pair(csi)) continue;
 
                cp = cf_item_to_pair(csi);
                name = cf_pair_attr(cp);
                value = cf_pair_value(cp);
 
                if (!value) {
                        cf_log_err(csi, "Retry configuration must specify a value");
                        return false;
                }
 
#define CLAMP(_name, _field, _limit) do { \
                        if (!fr_time_delta_ispos(actions->retry._field)) { \
                                cf_log_err(csi, "Invalid value for '" STRINGIFY(_name) " = %s' - value must be positive", \
                                           value); \
                                return false; \
                        } \
                        if (fr_time_delta_cmp(actions->retry._field, fr_time_delta_from_sec(_limit)) > 0) { \
                                cf_log_err(csi, "Invalid value for '" STRINGIFY(_name) " = %s' - value must be less than " STRINGIFY(_limit) "s", \
                                           value); \
                                return false; \
                        } \
        } while (0)
 
                /*
                 *      We don't use conf_parser_t here for various
                 *      magical reasons.
                 */
                if (strcmp(name, "initial_rtx_time") == 0) {
                        if (fr_time_delta_from_str(&actions->retry.irt, value, strlen(value), FR_TIME_RES_SEC) < 0) {
                        error:
                                cf_log_err(csi, "Failed parsing '%s = %s' - %s",
                                           name, value, fr_strerror());
                                return false;
                        }
                        CLAMP(initial_rtx_time, irt, 2);
 
                } else if (strcmp(name, "max_rtx_time") == 0) {
                        if (fr_time_delta_from_str(&actions->retry.mrt, value, strlen(value), FR_TIME_RES_SEC) < 0) goto error;
 
                        CLAMP(max_rtx_time, mrt, 10);
 
                } else if (strcmp(name, "max_rtx_count") == 0) {
                        char *end;
                        unsigned long v = strtoul(value, &end, 10);
 
                        if (*end || (end == value) || (v > 10)) {
                                cf_log_err(csi, "Invalid value for 'max_rtx_count = %s' - value must be between 0 and 10",
                                           value);
                                return false;
                        }
 
                        actions->retry.mrc = v;
 
                } else if (strcmp(name, "max_rtx_duration") == 0) {
                        if (fr_time_delta_from_str(&actions->retry.mrd, value, strlen(value), FR_TIME_RES_SEC) < 0) goto error;
 
                        CLAMP(max_rtx_duration, mrd, 20);
 
                } else {
                        cf_log_err(csi, "Invalid item '%s' in 'retry' configuration.", name);
                        return false;
                }
        }
 
        return true;
}
 
bool unlang_compile_actions(unlang_mod_actions_t *actions, CONF_SECTION *cs, bool module_retry)
{
        int i;
        bool disallow_retry_action = false;
        CONF_ITEM *csi;
 
        /*
         *      Over-ride the default return codes of the module.
         */
        for (csi=cf_item_next(cs, NULL);
             csi != NULL;
             csi=cf_item_next(cs, csi)) {
                char const *name;
                CONF_PAIR *cp;
 
                if (cf_item_is_section(csi)) {
                        CONF_SECTION *subcs = cf_item_to_section(csi);
 
                        name = cf_section_name1(subcs);
 
                        /*
                         *      Look for a "retry" section.
                         */
                        if (name && (strcmp(name, "retry") == 0) && !cf_section_name2(subcs)) {
                                if (!compile_retry_section(actions, csi)) return false;
                                continue;
                        }
 
                        cf_log_err(csi, "Invalid subsection.  Expected 'action = value'");
                        return false;
                }
 
                if (!cf_item_is_pair(csi)) continue;
 
                cp = cf_item_to_pair(csi);
 
                /*
                 *      Allow 'retry = path.to.retry.config'
                 */
                name = cf_pair_attr(cp);
                if (strcmp(name, "retry") == 0) {
                        CONF_ITEM *subci;
                        char const *value = cf_pair_value(cp);
 
                        if (!value) {
                                cf_log_err(csi, "Missing reference string");
                                return false;
                        }
 
                        subci = cf_reference_item(cs, cf_root(cf_section_to_item(cs)), value);
                        if (!subci) {
                                cf_log_perr(csi, "Failed finding reference '%s'", value);
                                return false;
                        }
 
                        if (!compile_retry_section(actions, subci)) return false;
                        continue;
                }
 
                if (!compile_action_pair(actions, cp)) {
                        return false;
                }
        }
 
        if (module_retry) {
                if (!fr_time_delta_ispos(actions->retry.irt)) {
                        cf_log_err(cs, "initial_rtx_time MUST be non-zero for modules which support retries.");
                        return false;
                }
        } else {
                if (fr_time_delta_ispos(actions->retry.irt)) {
                        cf_log_err(cs, "initial_rtx_time MUST be zero, as only max_rtx_count and max_rtx_duration are used.");
                        return false;
                }
 
                if (!actions->retry.mrc && !fr_time_delta_ispos(actions->retry.mrd)) {
                        disallow_retry_action = true;
                }
        }
 
        /*
         *      Sanity check that "fail = retry", we actually have a
         *      retry section.
         */
        for (i = 0; i < RLM_MODULE_NUMCODES; i++) {
                if (actions->actions[i] != MOD_ACTION_RETRY) continue;
 
                if (module_retry) {
                        cf_log_err(cs, "Cannot use a '%s = retry' action for a module which has its own retries",
                                   fr_table_str_by_value(mod_rcode_table, i, "<INVALID>"));
                        return false;
                }
 
                if (disallow_retry_action) {
                        cf_log_err(cs, "max_rtx_count and max_rtx_duration cannot both be zero when using '%s = retry'",
                                   fr_table_str_by_value(mod_rcode_table, i, "<INVALID>"));
                        return false;
                }
 
                if (!fr_time_delta_ispos(actions->retry.irt) &&
                    !actions->retry.mrc &&
                    !fr_time_delta_ispos(actions->retry.mrd)) {
                        cf_log_err(cs, "Cannot use a '%s = retry' action without a 'retry { ... }' section.",
                                   fr_table_str_by_value(mod_rcode_table, i, "<INVALID>"));
                        return false;
                }
        }
 
        return true;
}
 
unlang_t *unlang_compile_empty(unlang_t *parent, UNUSED unlang_compile_ctx_t *unlang_ctx, CONF_SECTION *cs, unlang_type_t type)
{
        unlang_group_t *g;
        unlang_t *c;
 
        /*
         *      If we're compiling an empty section, then the
         *      *interpreter* type is GROUP, even if the *debug names*
         *      are something else.
         */
        g = unlang_group_allocate(parent, cs, type);
        if (!g) return NULL;
 
        c = unlang_group_to_generic(g);
        if (!cs) {
                c->name = unlang_ops[type].name;
                c->debug_name = c->name;
 
        } else {
                char const *name2;
 
                name2 = cf_section_name2(cs);
                if (!name2) {
                        c->name = cf_section_name1(cs);
                        c->debug_name = c->name;
                } else {
                        c->name = name2;
                        c->debug_name = talloc_typed_asprintf(c, "%s %s", cf_section_name1(cs), name2);
                }
        }
 
        return c;
}
 
 
static unlang_t *compile_item(unlang_t *parent, unlang_compile_ctx_t *unlang_ctx, CONF_ITEM *ci);
 
/*
 *      compile 'actions { ... }' inside of another group.
 */
static bool compile_action_subsection(unlang_t *c, CONF_SECTION *cs, CONF_SECTION *subcs)
{
        CONF_ITEM *ci, *next;
 
        ci = cf_section_to_item(subcs);
 
        next = cf_item_next(cs, ci);
        if (next && (cf_item_is_pair(next) || cf_item_is_section(next))) {
                cf_log_err(ci, "'actions' MUST be the last block in a section");
                return false;
        }
 
        if (cf_section_name2(subcs) != NULL) {
                cf_log_err(ci, "Invalid name for 'actions' section");
                return false;
        }
 
        /*
         *      Over-riding the actions can be done in certain limited
         *      situations.  In other situations (e.g. "redundant",
         *      "load-balance"), it doesn't make sense.
         *
         *      Note that this limitation also applies to "retry"
         *      timers.  We can do retries of a "group".  We cannot do
         *      retries of "load-balance", as the "load-balance"
         *      section already takes care of redundancy.
         *
         *      We may need to loosen that limitation in the future.
         */
        switch (c->type) {
        case UNLANG_TYPE_CASE:
        case UNLANG_TYPE_CATCH:
        case UNLANG_TYPE_IF:
        case UNLANG_TYPE_ELSE:
        case UNLANG_TYPE_ELSIF:
        case UNLANG_TYPE_FOREACH:
        case UNLANG_TYPE_GROUP:
        case UNLANG_TYPE_LIMIT:
        case UNLANG_TYPE_SWITCH:
        case UNLANG_TYPE_TIMEOUT:
        case UNLANG_TYPE_TRANSACTION:
                break;
 
        default:
                cf_log_err(ci, "'actions' MUST NOT be in a '%s' block", unlang_ops[c->type].name);
                return false;
        }
 
        return unlang_compile_actions(&c->actions, subcs, false);
}
 
 
unlang_t *unlang_compile_children(unlang_group_t *g, unlang_compile_ctx_t *unlang_ctx_in)
{
        CONF_ITEM       *ci = NULL;
        unlang_t        *c, *single;
        bool            was_if = false;
        char const      *skip_else = NULL;
        unlang_compile_ctx_t *unlang_ctx;
        unlang_compile_ctx_t unlang_ctx2;
        tmpl_rules_t    t_rules, t2_rules; /* yes, it does */
 
        c = unlang_group_to_generic(g);
 
        /*
         *      Create our own compilation context which can be edited
         *      by a variable definition.
         */
        unlang_compile_ctx_copy(&unlang_ctx2, unlang_ctx_in);
        t2_rules = *(unlang_ctx_in->rules);
 
        unlang_ctx = &unlang_ctx2;
        unlang_ctx2.rules = &t2_rules;
 
        t_rules = *unlang_ctx_in->rules;
 
        /*
         *      Loop over the children of this group.
         */
        while ((ci = cf_item_next(g->cs, ci))) {
                if (cf_item_is_data(ci)) continue;
 
                t_rules.attr.ci = ci;
                t2_rules.attr.ci = ci;
 
                /*
                 *      Sections are keywords, or references to
                 *      modules with updated return codes.
                 */
                if (cf_item_is_section(ci)) {
                        char const *name = NULL;
                        CONF_SECTION *subcs = cf_item_to_section(ci);
 
                        /*
                         *      Skip precompiled blocks.  This is
                         *      mainly for policies.
                         */
                        if (cf_data_find(subcs, unlang_group_t, NULL)) continue;
 
                        /*
                         *      "actions" apply to the current group.
                         *      It's not a subgroup.
                         */
                        name = cf_section_name1(subcs);
 
                        /*
                         *      In-line attribute editing.  Nothing else in the parse has list assignments, so this must be it.
                         */
                        if (fr_list_assignment_op[cf_section_name2_quote(subcs)]) {
                                single = compile_edit_section(c, unlang_ctx, subcs);
                                if (!single) {
                                fail:
                                        talloc_free(c);
                                        return NULL;
                                }
 
                                goto add_child;
                        }
 
                        if (strcmp(name, "actions") == 0) {
                                if (!compile_action_subsection(c, g->cs, subcs)) goto fail;
                                continue;
                        }
 
                        /*
                         *      Special checks for "else" and "elsif".
                         */
                        if ((strcmp(name, "else") == 0) || (strcmp(name, "elsif") == 0)) {
                                /*
                                 *      We ran into one without a preceding "if" or "elsif".
                                 *      That's not allowed.
                                 */
                                if (!was_if) {
                                        cf_log_err(ci, "Invalid location for '%s'.  There is no preceding "
                                                   "'if' or 'elsif' statement", name);
                                        goto fail;
                                }
 
                                /*
                                 *      There was a previous "if" or "elsif" which was always taken.
                                 *      So we skip this "elsif" or "else".
                                 */
                                if (skip_else) {
                                        void *ptr;
 
                                        /*
                                         *      And manually free this.
                                         */
                                        ptr = cf_data_remove(subcs, xlat_exp_head_t, NULL);
                                        talloc_free(ptr);
 
                                        cf_section_free_children(subcs);
 
                                        cf_log_debug_prefix(ci, "Skipping contents of '%s' due to previous "
                                                            "'%s' always being taken.",
                                                            name, skip_else);
                                        continue;
                                }
                        }
 
                        /*
                         *      Otherwise it's a real keyword.
                         */
                        single = compile_item(c, unlang_ctx, ci);
                        if (!single) {
                                cf_log_err(ci, "Failed to parse \"%s\" subsection", cf_section_name1(subcs));
                                goto fail;
                        }
 
                        goto add_child;
 
                } else if (cf_item_is_pair(ci)) {
                        CONF_PAIR *cp = cf_item_to_pair(ci);
 
                        /*
                         *      Variable definition.
                         */
                        if (cf_pair_operator(cp) == T_OP_CMP_TRUE) {
                                if (compile_variable(c, unlang_ctx, cp, &t_rules) < 0) goto fail;
 
                                single = UNLANG_IGNORE;
                                goto add_child;
                        }
 
                        if (!cf_pair_value(cp)) {
                                single = compile_item(c, unlang_ctx, ci);
                                if (!single) {
                                        cf_log_err(ci, "Invalid keyword \"%s\".", cf_pair_attr(cp));
                                        goto fail;
                                }
 
                                goto add_child;
                        }
 
                        /*
                         *      What remains MUST be an edit pair.  At this point, the state of the compiler
                         *      tells us what it is, and we don't really care if there's a leading '&'.
                         */
                        single = compile_edit_pair(c, unlang_ctx, cp);
                        if (!single) goto fail;
 
                        goto add_child;
                } else {
                        cf_log_err(ci, "Asked to compile unknown conf type");
                        goto fail;
                }
 
        add_child:
                if (single == UNLANG_IGNORE) continue;
 
                /*
                 *      Do optimizations for "if" and "elsif"
                 *      conditions.
                 */
                switch (single->type) {
                case UNLANG_TYPE_ELSIF:
                case UNLANG_TYPE_IF:
                        was_if = true;
 
                        {
                                unlang_group_t  *f;
                                unlang_cond_t   *gext;
 
                                /*
                                 *      Skip else, and/or omit things which will never be run.
                                 */
                                f = unlang_generic_to_group(single);
                                gext = unlang_group_to_cond(f);
 
                                if (gext->is_truthy) {
                                        if (gext->value) {
                                                skip_else = single->debug_name;
                                        } else {
                                                /*
                                                 *      If this came from compile_single, then it will already
                                                 *      have a number and be in the tree.
                                                 */
                                                if (single->number) fr_rb_remove(unlang_instruction_tree, single);
 
                                                /*
                                                 *      The condition never
                                                 *      matches, so we can
                                                 *      avoid putting it into
                                                 *      the unlang tree.
                                                 */
                                                talloc_free(single);
                                                continue;
                                        }
                                }
                        }
                        break;
 
                default:
                        was_if = false;
                        skip_else = NULL;
                        break;
                }
 
                /*
                 *      unlang_group_t is grown by adding a unlang_t to the end
                 */
                fr_assert(g == talloc_parent(single));
                fr_assert(single->parent == unlang_group_to_generic(g));
                unlang_list_insert_tail(&g->children, single);
                single->list = &g->children;
 
                /*
                 *      If it's not possible to execute statement
                 *      after the current one, then just stop
                 *      processing the children.
                 */
                if (g->self.closed) {
                        cf_log_warn(ci, "Skipping remaining instructions due to '%s'",
                                    single->name);
                        break;
                }
        }
 
        return c;
}
 
 
/*
 *      Generic "compile a section with more unlang inside of it".
 */
unlang_t *unlang_compile_section(unlang_t *parent, unlang_compile_ctx_t *unlang_ctx, CONF_SECTION *cs, unlang_type_t type)
{
        unlang_group_t  *g;
        unlang_t        *c;
        char const      *name1, *name2;
 
        fr_assert(unlang_ctx->rules != NULL);
        fr_assert(unlang_ctx->rules->attr.list_def);
 
        /*
         *      We always create a group, even if the section is empty.
         */
        g = unlang_group_allocate(parent, cs, type);
        if (!g) return NULL;
 
        c = unlang_group_to_generic(g);
 
        /*
         *      Remember the name for printing, etc.
         */
        name1 = cf_section_name1(cs);
        name2 = cf_section_name2(cs);
        c->name = name1;
 
        /*
         *      Make sure to tell the user that we're running a
         *      policy, and not anything else.
         */
        if (type == UNLANG_TYPE_POLICY) {
                MEM(c->debug_name = talloc_typed_asprintf(c, "policy %s", name1));
 
        } else if (!name2) {
                c->debug_name = c->name;
 
        } else {
                MEM(c->debug_name = talloc_typed_asprintf(c, "%s %s", name1, name2));
        }
 
        return unlang_compile_children(g, unlang_ctx);
}
 
 
static unlang_t *compile_tmpl(unlang_t *parent, unlang_compile_ctx_t *unlang_ctx, CONF_ITEM *ci)
{
        CONF_PAIR       *cp = cf_item_to_pair(ci);
        unlang_t        *c;
        unlang_tmpl_t   *ut;
        ssize_t         slen;
        char const      *p = cf_pair_attr(cp);
        tmpl_t          *vpt;
 
        MEM(ut = talloc_zero(parent, unlang_tmpl_t));
        c = unlang_tmpl_to_generic(ut);
        unlang_type_init(c, parent, UNLANG_TYPE_TMPL);
        c->name = p;
        c->debug_name = c->name;
        c->ci = CF_TO_ITEM(cp);
 
        RULES_VERIFY(unlang_ctx->rules);
        slen = tmpl_afrom_substr(ut, &vpt,
                                 &FR_SBUFF_IN(p, talloc_strlen(p)),
                                 cf_pair_attr_quote(cp),
                                 NULL,
                                 unlang_ctx->rules);
        if (!vpt) {
                cf_canonicalize_error(cp, slen, "Failed parsing expansion", p);
                talloc_free(ut);
                return NULL;
        }
        ut->tmpl = vpt; /* const issues */
 
        return c;
}
 
/*
 *      redundant, load-balance and parallel have limits on what can
 *      go in them.
 */
bool unlang_compile_limit_subsection(CONF_SECTION *cs, char const *name)
{
        CONF_ITEM *ci;
 
        for (ci=cf_item_next(cs, NULL);
             ci != NULL;
             ci=cf_item_next(cs, ci)) {
                /*
                 *      If we're a redundant, etc. group, then the
                 *      intention is to call modules, rather than
                 *      processing logic.  These checks aren't
                 *      *strictly* necessary, but they keep the users
                 *      from doing crazy things.
                 */
                if (cf_item_is_section(ci)) {
                        CONF_SECTION *subcs = cf_item_to_section(ci);
                        char const *name1 = cf_section_name1(subcs);
 
                        /*
                         *      Allow almost anything except "else"
                         *      statements.  The normal processing
                         *      falls through from "if" to "else", and
                         *      we can't do that for redundant and
                         *      load-balance sections.
                         */
                        if ((strcmp(name1, "else") == 0) ||
                            (strcmp(name1, "elsif") == 0)) {
                                cf_log_err(ci, "%s sections cannot contain a \"%s\" statement",
                                       name, name1);
                                return false;
                        }
                        continue;
                }
 
                if (cf_item_is_pair(ci)) {
                        CONF_PAIR *cp = cf_item_to_pair(ci);
 
                        if (cf_pair_operator(cp) == T_OP_CMP_TRUE) continue;
 
                        if (cf_pair_value(cp) != NULL) {
                                cf_log_err(cp, "Unknown keyword '%s', or invalid location", cf_pair_attr(cp));
                                return false;
                        }
                }
        }
 
        return true;
}
 
 
static unlang_t *compile_function(unlang_t *parent, unlang_compile_ctx_t *unlang_ctx, CONF_ITEM *ci,
                                  CONF_SECTION *subcs,
                                  bool policy)
{
        unlang_compile_ctx_t            unlang_ctx2;
        unlang_t                        *c;
 
        UPDATE_CTX2;
 
        /*
         *      module.c takes care of ensuring that this is:
         *
         *      group foo { ...
         *      load-balance foo { ...
         *      redundant foo { ...
         *      redundant-load-balance foo { ...
         *
         *      We can just recurse to compile the section as
         *      if it was found here.
         */
        if (cf_section_name2(subcs)) {
                if (policy) {
                        cf_log_err(subcs, "Unexpected second name in policy");
                        return NULL;
                }
 
                c = compile_item(parent, &unlang_ctx2, cf_section_to_item(subcs));
 
        } else {
                /*
                 *      We have:
                 *
                 *      foo { ...
                 *
                 *      So we compile it like it was:
                 *
                 *      group foo { ...
                 */
                c = unlang_compile_section(parent, &unlang_ctx2, subcs,
                                    policy ? UNLANG_TYPE_POLICY : UNLANG_TYPE_GROUP);
        }
        if (!c) return NULL;
        fr_assert(c != UNLANG_IGNORE);
 
        /*
         *      Return the compiled thing if we can.
         */
        if (!cf_item_is_section(ci)) return c;
 
        /*
         *      Else we have a reference to a policy, and that reference
         *      over-rides the return codes for the policy!
         */
        if (!unlang_compile_actions(&c->actions, cf_item_to_section(ci), false)) {
                talloc_free(c);
                return NULL;
        }
 
        return c;
}
 
/** Load a named module from the virtual module list, or from the "policy" subsection.
 *
 * If it's "foo.method", look for "foo", and return "method" as the method
 * we wish to use, instead of the input component.
 *
 * @param[in] ci                Configuration item to check
 * @param[in] real_name         Complete name string e.g. foo.authorize.
 * @param[in] virtual_name      Virtual module name e.g. foo.
 * @param[in] method_name       Method override (may be NULL) or the method
 *                              name e.g. authorize.
 * @param[in] unlang_ctx        Unlang context this call is being compiled in.
 * @param[out] policy           whether or not this thing was a policy
 * @return the CONF_SECTION specifying the virtual module.
 */
static CONF_SECTION *virtual_module_find_cs(CONF_ITEM *ci, UNUSED char const *real_name, char const *virtual_name,
                                            char const *method_name, unlang_compile_ctx_t *unlang_ctx, bool *policy)
{
        CONF_SECTION *cs, *subcs, *conf_root;
        CONF_ITEM *loop;
        char buffer[256];
 
        *policy = false;
        conf_root = cf_root(ci);
 
        /*
         *      Look for "foo" as a virtual server.  If we find it,
         *      AND there's no method name, we've found the right
         *      thing.
         *
         *      Found "foo".  Load it as "foo", or "foo.method".
         *
         *      Return it to the caller, with the updated method.
         */
        subcs = module_rlm_virtual_by_name(virtual_name);
        if (subcs) goto check_for_loop;
 
        /*
         *      Look for it in "policy".
         *
         *      If there's no policy section, we can't do anything else.
         */
        cs = cf_section_find(conf_root, "policy", NULL);
        if (!cs) return NULL;
 
        *policy = true;
 
        /*
         *      "foo.authorize" means "load policy 'foo.authorize' or 'foo'"
         *      as method "authorize".
         *
         *      And bail out if there's no policy "foo.authorize" or "foo".
         */
        if (method_name) {
                snprintf(buffer, sizeof(buffer), "%s.%s", virtual_name, method_name);
                subcs = cf_section_find(cs, buffer, NULL);
                if (!subcs) subcs = cf_section_find(cs, virtual_name, NULL);
                if (!subcs) return NULL;
 
                goto check_for_loop;
        }
 
        /*
         *      "foo" means "look for foo.name1.name2" first, to allow
         *      method overrides.  If that's not found, look for
         *      "foo.name1" and if that's not found just look for
         *      a policy "foo".
         */
        if (unlang_ctx->section_name2) {
                snprintf(buffer, sizeof(buffer), "%s.%s.%s", virtual_name, unlang_ctx->section_name1, unlang_ctx->section_name2);
                subcs = cf_section_find(cs, buffer, NULL);
        } else {
                subcs = NULL;
        }
 
        if (!subcs) {
                snprintf(buffer, sizeof(buffer), "%s.%s", virtual_name, unlang_ctx->section_name1);
                subcs = cf_section_find(cs, buffer, NULL);
        }
 
        if (!subcs) subcs = cf_section_find(cs, virtual_name, NULL);
        if (!subcs) return NULL;
 
check_for_loop:
        /*
         *      Check that we're not creating a loop.  We may
         *      be compiling an "sql" module reference inside
         *      of an "sql" policy.  If so, we allow the
         *      second "sql" to refer to the module.
         */
        for (loop = cf_parent(ci);
             loop && subcs;
             loop = cf_parent(loop)) {
                if (loop == cf_section_to_item(subcs)) {
                        return NULL;
                }
        }
 
        return subcs;
}
 
static unlang_t *compile_module(unlang_t *parent, unlang_compile_ctx_t *unlang_ctx, CONF_ITEM *ci, char const *name)
{
        unlang_t        *c;
        unlang_module_t *m;
        fr_slen_t       slen;
 
        MEM(m = talloc_zero(parent, unlang_module_t));
        slen = module_rlm_by_name_and_method(m, &m->mmc,
                                             unlang_ctx->vs,
                                             &(section_name_t){ .name1 = unlang_ctx->section_name1, .name2 = unlang_ctx->section_name2 },
                                             &FR_SBUFF_IN_STR(name),
                                             unlang_ctx->rules);
        if (slen < 0) {
                cf_log_perr(ci, "Failed compiling module call");
                talloc_free(m);
                return NULL;
        }
 
        /*
         *      We parsed a string, but we were told to ignore it.  Don't do anything.
         */
        if (!m->mmc.rlm) return UNLANG_IGNORE;
 
        if (m->mmc.rlm->common.dict &&
            !fr_dict_compatible(*m->mmc.rlm->common.dict, unlang_ctx->rules->attr.dict_def)) {
                cf_log_err(ci, "The '%s' module can only be used within a '%s' namespace.",
                           m->mmc.rlm->common.name, fr_dict_root(*m->mmc.rlm->common.dict)->name);
                cf_log_err(ci, "Please use the 'subrequest' keyword to change namespaces");
                cf_log_err(ci, DOC_KEYWORD_REF(subrequest));
                talloc_free(m);
                return NULL;
        }
 
        c = unlang_module_to_generic(m);
        unlang_type_init(c, parent, UNLANG_TYPE_MODULE);
        c->name = talloc_strdup(c, name);
        c->debug_name = c->name;
        c->ci = ci;
 
        /*
         *      Set the default actions for this module.
         */
        c->actions = m->mmc.mi->actions;
 
        /*
         *      Parse the method environment for this module / method
         */
        if (m->mmc.mmb.method_env) {
                call_env_method_t const *method_env = m->mmc.mmb.method_env;
 
                fr_assert_msg(method_env->inst_size, "Method environment for module %s, method %s %s declared, "
                              "but no inst_size set",
                              m->mmc.mi->name, unlang_ctx->section_name1, unlang_ctx->section_name2);
 
                if (!unlang_ctx->rules) {
                        cf_log_err(ci, "Failed compiling %s - no rules",  m->mmc.mi->name);
                        goto error;
                }
                m->call_env = call_env_alloc(m, m->self.name, method_env,
                                             unlang_ctx->rules, m->mmc.mi->conf,
                                             &(call_env_ctx_t){
                                                .type = CALL_ENV_CTX_TYPE_MODULE,
                                                .mi = m->mmc.mi,
                                                .asked = &m->mmc.asked
                                             });
                if (!m->call_env) {
                error:
                        talloc_free(m);
                        return NULL;
                }
        }
 
        /*
         *      If a module reference is a section, then the section
         *      should contain action over-rides.  We add those here.
         */
        if (cf_item_is_section(ci) &&
            !unlang_compile_actions(&c->actions, cf_item_to_section(ci),
                                    (m->mmc.mi->exported->flags & MODULE_TYPE_RETRY) != 0)) goto error;
 
        return c;
}
 
extern int dict_attr_acopy_children(fr_dict_t *dict, fr_dict_attr_t *dst, fr_dict_attr_t const *src);
 
#define name_to_op(name)  fr_hash_table_find(unlang_op_table, &(unlang_op_t) { .name = name })
 
int unlang_define_local_variable(CONF_ITEM *ci, unlang_variable_t *var, tmpl_rules_t *t_rules, fr_type_t type, char const *name,
                                 fr_dict_attr_t const *ref)
{
        fr_dict_attr_t const *da;
        fr_slen_t len;
        unlang_op_t const *op;
 
        fr_dict_attr_flags_t flags = {
                .internal = true,
                .local = true,
        };
 
        /*
         *      No overlap with list names.
         */
        if (fr_table_value_by_str(tmpl_request_ref_table, name, REQUEST_UNKNOWN) != REQUEST_UNKNOWN) {
        fail_list:
                cf_log_err(ci, "Local variable '%s' cannot be a list reference.", name);
                return -1;
        }
 
        len = strlen(name);
        if (tmpl_attr_list_from_substr(&da, &FR_SBUFF_IN(name, len)) == len) goto fail_list;
 
        /*
         *      No keyword section names.
         */
        op = name_to_op(name);
        if (op) {
                cf_log_err(ci, "Local variable '%s' cannot be an unlang keyword.", name);
                return -1;
        }
 
        /*
         *      No protocol names.
         */
        if (fr_dict_by_protocol_name(name) != NULL) {
                cf_log_err(ci, "Local variable '%s' cannot be an existing protocol name.", name);
                return -1;
        }
 
        /*
         *      No overlap with attributes in the current dictionary.  The lookup in var->root will also check
         *      the current dictionary, so the check here is really only for better error messages.
         */
        if (t_rules && t_rules->parent && t_rules->parent->attr.dict_def) {
                da = fr_dict_attr_by_name(NULL, fr_dict_root(t_rules->parent->attr.dict_def), name);
                if (da) {
                        cf_log_err(ci, "Local variable '%s' duplicates a dictionary attribute.", name);
                        return -1;
                }
        }
 
        /*
         *      No data types.
         */
        if (fr_table_value_by_str(fr_type_table, name, FR_TYPE_NULL) != FR_TYPE_NULL) {
                cf_log_err(ci, "Invalid variable name '%s'.", name);
                return -1;
        }
 
        /*
         *      No dups of local variables.
         */
        da = fr_dict_attr_by_name(NULL, var->root, name);
        if (da) {
                cf_log_err(ci, "Duplicate variable name '%s'.", name);
                return -1;
        }
 
        if (fr_dict_attr_add(var->dict, var->root, name, var->max_attr, type, &flags) < 0) {
        fail:
                cf_log_err(ci, "Failed adding variable '%s' - %s", name, fr_strerror());
                return -1;
        }
        da = fr_dict_attr_by_name(NULL, var->root, name);
        fr_assert(da != NULL);
 
        /*
         *      Copy the children over.
         */
        var->max_attr++;
        if (fr_type_is_structural(type) && (type != FR_TYPE_GROUP)) {
                fr_fatal_assert(ref != NULL);
 
                if (fr_dict_attr_acopy_local(da, ref) < 0) goto fail;
        }
 
 
        return 0;
}
 
/*
 *      Compile one unlang instruction
 */
static unlang_t *compile_item(unlang_t *parent, unlang_compile_ctx_t *unlang_ctx, CONF_ITEM *ci)
{
        char const              *name, *p;
        CONF_SECTION            *cs, *subcs, *modules;
        unlang_compile_ctx_t    unlang_ctx2;
        bool                    policy;
        unlang_t                *c;
        unlang_op_t const       *op;
 
        if (cf_item_is_section(ci)) {
                cs = cf_item_to_section(ci);
                name = cf_section_name1(cs);
                op = name_to_op(name);
 
                if (op) {
                        /*
                         *      Forbid pair keywords as section names,
                         *      e.g. "break { ... }"
                         */
                        if ((op->flag & UNLANG_OP_FLAG_SINGLE_WORD) != 0) {
                                cf_log_err(ci, "Syntax error after keyword '%s' - unexpected '{'", name);
                                return NULL;
                        }
 
                        c = op->compile(parent, unlang_ctx, ci);
                        goto allocate_number;
                }
 
                /* else it's something like sql { fail = 1 ...} */
                goto check_for_module;
 
        } else if (cf_item_is_pair(ci)) {
 
                /*
                 *      Else it's a module reference such as "sql", OR
                 *      one of the few bare keywords that we allow.
                 */
                CONF_PAIR *cp = cf_item_to_pair(ci);
 
                /*
                 *      We cannot have assignments or actions here.
                 */
                if (cf_pair_value(cp) != NULL) {
                        cf_log_err(ci, "Invalid assignment");
                        return NULL;
                }
 
                name = cf_pair_attr(cp);
                op = name_to_op(name);
 
                if (op) {
                        /*
                         *      Forbid section keywords as pair names, e.g. "switch = foo"
                         */
                        if ((op->flag & UNLANG_OP_FLAG_SINGLE_WORD) == 0) {
                                cf_log_err(ci, "Syntax error after keyword '%s' - missing '{'", name);
                                return NULL;
                        }
 
                        c = op->compile(parent, unlang_ctx, ci);
                        goto allocate_number;
                }
 
                /*
                 *      In-place expansions.
                 *
                 *      @todo - allow only function calls, not %{...}
                 *
                 *      @todo don't create a tmpl.  Instead, create an
                 *      xlat.  This functionality is needed for the in-place language functions via
                 *
                 *      language {{{
                 *              ...
                 *      }}}
                 */
                if (name[0] == '%') {
                        c = compile_tmpl(parent, unlang_ctx, cf_pair_to_item(cp));
                        goto allocate_number;
                }
 
                goto check_for_module;
 
        } else {
                cf_log_err(ci, "Asked to compile unknown configuration item");
                return NULL;    /* who knows what it is... */
        }
 
check_for_module:
        /*
         *      We now have a name.  It can be one of two forms.  A
         *      bare module name, or a section named for the module,
         *      with over-rides for the return codes.
         *
         *      The name can refer to a real module, in the "modules"
         *      section.  In that case, the name will be either the
         *      first or second name of the sub-section of "modules".
         *
         *      Or, the name can refer to a policy, in the "policy"
         *      section.  In that case, the name will be first of the
         *      sub-section of "policy".
         *
         *      Or, the name can refer to a "module.method", in which
         *      case we're calling a different method than normal for
         *      this section.
         *
         *      Or, the name can refer to a virtual module, in the
         *      "modules" section.  In that case, the name will be
         *      name2 of the CONF_SECTION.
         *
         *      We try these in sequence, from the bottom up.  This is
         *      so that virtual modules and things in "policy" can
         *      over-ride calls to real modules.
         */
 
 
        /*
         *      Try:
         *
         *      policy { ... name { .. } .. }
         *      policy { ... name.method { .. } .. }
         */
        p = strrchr(name, '.');
        if (!p) {
                subcs = virtual_module_find_cs(ci, name, name, NULL, unlang_ctx, &policy);
        } else {
                char buffer[256];
 
                strlcpy(buffer, name, sizeof(buffer));
                buffer[p - name] = '\0';
 
                subcs = virtual_module_find_cs(ci, name,
                                               buffer, buffer + (p - name) + 1, unlang_ctx, &policy);
        }
 
        /*
         *      We've found the thing which defines this "function".
         *      It MUST be a sub-section.
         *
         *      i.e. it refers to a a subsection in "policy".
         */
        if (subcs) {
                c = compile_function(parent, unlang_ctx, ci, subcs, policy);
                goto allocate_number;
        }
 
        /*
         *      Not a function.  It must be a real module.
         */
        modules = cf_section_find(cf_root(ci), "modules", NULL);
        if (!modules) {
                cf_log_err(ci, "Failed compiling \"%s\" as a module or policy as no modules are enabled", name);
                cf_log_err(ci, "Please verify that modules { ... }  section is present in the server configuration");
                return NULL;
        }
 
        /*
         *      Set the child compilation context BEFORE parsing the
         *      module name and method.  The lookup function will take
         *      care of returning the appropriate component, name1,
         *      name2, etc.
         */
        UPDATE_CTX2;
        c = compile_module(parent, &unlang_ctx2, ci, name);
 
allocate_number:
        if (!c) return NULL;
        if (c == UNLANG_IGNORE) return UNLANG_IGNORE;
 
        /*
         *      Some compilation paths already go through this path
         *      and will have assigned a number.
         */
        if (c->number) return c;
 
        c->number = unlang_number++;
        compile_set_default_actions(c, unlang_ctx);
 
        if (!fr_rb_insert(unlang_instruction_tree, c)) {
                cf_log_err(ci, "Instruction \"%s\" number %u has conflict with previous one.",
                           c->debug_name, c->number);
                talloc_free(c);
                return NULL;
        }
 
        return c;
}
 
/** Compile an unlang section for a virtual server
 *
 * @param[in] vs                Virtual server to compile section for.
 * @param[in] cs                containing the unlang calls to compile.
 * @param[in] actions           Actions to use for the unlang section.
 * @param[in] rules             Rules to use for the unlang section.
 * @param[out] instruction      Pointer to store the compiled unlang section.
 * @return
 *      - 0 on success.
 *      - -1 on error.
 */
int unlang_compile(virtual_server_t const *vs,
                   CONF_SECTION *cs, unlang_mod_actions_t const *actions, tmpl_rules_t const *rules, void **instruction)
{
        unlang_t                        *c;
        char const                      *name1, *name2;
        CONF_DATA const                 *cd;
 
        /*
         *      Don't compile it twice, and don't print out debug
         *      messages twice.
         */
        cd = cf_data_find(cs, unlang_group_t, NULL);
        if (cd) {
                if (instruction) *instruction = cf_data_value(cd);
                return 1;
        }
 
        /*
         *      Ensure that all compile functions get valid rules.
         */
        if (!rules) {
                cf_log_err(cs, "Failed compiling section - no namespace rules passed");
                return -1;
        }
 
        name1 = cf_section_name1(cs);
        name2 = cf_section_name2(cs);
 
        if (!name2) name2 = "";
 
        cf_log_debug(cs, "Compiling policies in - %s %s {...}", name1, name2);
 
        c = unlang_compile_section(NULL,
                            &(unlang_compile_ctx_t){
                                .vs = vs,
                                .section_name1 = cf_section_name1(cs),
                                .section_name2 = cf_section_name2(cs),
                                .actions = *actions,
                                .rules = rules
                            },
                            cs, UNLANG_TYPE_GROUP);
        if (!c) return -1;
 
        fr_assert(c != UNLANG_IGNORE);
 
        if (DEBUG_ENABLED4) unlang_dump(c, 2);
 
        /*
         *      Associate the unlang_t with the configuration section.
         *      It's already parented from "cs", so don't free it.
         */
        cf_data_add(cs, c, NULL, false);
        cf_item_mark_parsed(cs);
        if (instruction) *instruction = c;
 
        return 0;
}
 
 
/** Check if name is an unlang keyword
 *
 * @param[in] name      to check.
 * @return
 *      - true if it is a keyword.
 *      - false if it's not a keyword.
 */
bool unlang_compile_is_keyword(const char *name)
{
        if (!name || !*name) return false;
 
        return (name_to_op(name) != NULL);
}
 
/*
 *      These are really unlang_foo_t, but that's fine...
 */
static int8_t instruction_cmp(void const *one, void const *two)
{
        unlang_t const *a = one;
        unlang_t const *b = two;
 
        return CMP(a->number, b->number);
}
 
 
void unlang_compile_init(TALLOC_CTX *ctx)
{
        unlang_instruction_tree = fr_rb_alloc(ctx, instruction_cmp, NULL);
}