catch.c

Go to the documentation of this file.

/*
 *   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: 70ef78fb7dd8c6b5878ad275e4acd2d4737c6714 $
 *
 * @file unlang/catch.c
 * @brief Unlang "catch" keyword evaluation.
 *
 * @copyright 2023 Network RADIUS SAS (legal@networkradius.com)
 */
RCSID("$Id: 70ef78fb7dd8c6b5878ad275e4acd2d4737c6714 $")
 
#include <freeradius-devel/server/rcode.h>
#include "unlang_priv.h"
#include "catch_priv.h"
 
static unlang_action_t catch_skip_to_next(UNUSED unlang_result_t *p_result, UNUSED request_t *request, unlang_stack_frame_t *frame)
{
        unlang_t                *unlang;
 
        fr_assert(frame->instruction->type == UNLANG_TYPE_CATCH);
 
        for (unlang = frame->instruction->next;
             unlang != NULL;
             unlang = unlang->next) {
                if (unlang->type == UNLANG_TYPE_CATCH) continue;
 
                break;
        }
 
        return frame_set_next(frame, unlang);
}
 
static unlang_action_t unlang_catch(UNUSED unlang_result_t *p_result, request_t *request, unlang_stack_frame_t *frame)
{
#ifndef NDEBUG
        unlang_catch_t const *c = unlang_generic_to_catch(frame->instruction);
 
        fr_assert(!c->catching[p_result->rcode]);
#endif
 
        /*
         *      Skip over any "catch" statementa after this one.
         */
        frame_repeat(frame, catch_skip_to_next);
 
        return unlang_interpret_push_children(NULL, request, RLM_MODULE_NOT_SET, UNLANG_NEXT_SIBLING);
}
 
 
/** Skip ahead to a particular "catch" instruction.
 *
 */
unlang_action_t unlang_interpret_skip_to_catch(UNUSED unlang_result_t *p_result, request_t *request, unlang_stack_frame_t *frame)
{
        unlang_t                *unlang;
        rlm_rcode_t             rcode = unlang_interpret_rcode(request);
 
        fr_assert(frame->instruction->type == UNLANG_TYPE_TRY);
 
        /*
         *      'try' at the end of a block without 'catch' should have been caught by the compiler.
         */
        fr_assert(frame->instruction->next);
 
        for (unlang = frame->instruction->next;
             unlang != NULL;
             unlang = unlang->next) {
                unlang_catch_t const *c;
 
                if (unlang->type != UNLANG_TYPE_CATCH) {
                not_caught:
                        RDEBUG3("No catch section for %s",
                                fr_table_str_by_value(mod_rcode_table, rcode, "<invalid>"));
                        return frame_set_next(frame, unlang);
                }
 
                if (rcode >= RLM_MODULE_NUMCODES) continue;
 
                c = unlang_generic_to_catch(unlang);
                if (c->catching[rcode]) break;
        }
        if (!unlang) goto not_caught;
 
        return frame_set_next(frame, unlang);
}
 
static int catch_argv(CONF_SECTION *cs, unlang_catch_t *ca, char const *name)
{
        int rcode;
 
        rcode = fr_table_value_by_str(mod_rcode_table, name, -1);
        if (rcode < 0) {
                cf_log_err(cs, "Unknown rcode '%s'.", name);
                return -1;
        }
 
        if (ca->catching[rcode]) {
                cf_log_err(cs, "Duplicate rcode '%s'.", name);
                return -1;
        }
 
        ca->catching[rcode] = true;
 
        return 0;
}
 
static unlang_t *unlang_compile_catch(unlang_t *parent, unlang_compile_ctx_t *unlang_ctx, CONF_ITEM const *ci)
{
        CONF_SECTION *cs = cf_item_to_section(ci);
        unlang_group_t *g;
        unlang_t *c;
        unlang_catch_t *ca;
        CONF_ITEM *prev;
        char const *name;
 
        prev = cf_item_prev(cf_parent(ci), ci);
        while (prev && cf_item_is_data(prev)) prev = cf_item_prev(cf_parent(ci), prev);
 
        if (!prev || !cf_item_is_section(prev)) {
        fail:
                cf_log_err(cs, "Found 'catch' section with no previous 'try'");
                cf_log_err(ci, DOC_KEYWORD_REF(catch));
                return NULL;
        }
 
        name = cf_section_name1(cf_item_to_section(prev));
        fr_assert(name != NULL);
 
        if ((strcmp(name, "try") != 0) && (strcmp(name, "catch") != 0)) {
                /*
                 *      The previous thing has to be a section.  And it has to
                 *      be either a "try" or a "catch".
                 */
                goto fail;
        }
 
        g = unlang_group_allocate(parent, cs, UNLANG_TYPE_CATCH);
        if (!g) return NULL;
 
        c = unlang_group_to_generic(g);
 
        /*
         *      Want to log what we caught
         */
        c->debug_name = c->name = talloc_typed_asprintf(c, "%s %s", cf_section_name1(cs), cf_section_name2(cs));
 
        ca = unlang_group_to_catch(g);
        if (!cf_section_name2(cs)) {
                /*
                 *      No arg2: catch errors
                 */
                ca->catching[RLM_MODULE_REJECT] = true;
                ca->catching[RLM_MODULE_FAIL] = true;
                ca->catching[RLM_MODULE_INVALID] = true;
                ca->catching[RLM_MODULE_DISALLOW] = true;
 
        } else {
                int i;
 
                name = cf_section_name2(cs);
 
                if (catch_argv(cs, ca, name) < 0) {
                        talloc_free(c);
                        return NULL;
                }
 
                for (i = 0; (name = cf_section_argv(cs, i)) != NULL; i++) {
                        if (catch_argv(cs, ca, name) < 0) {
                                talloc_free(c);
                                return NULL;
                        }
                }
        }
 
        /*
         *      @todo - Else parse and limit the things we catch
         */
        return unlang_compile_children(g, unlang_ctx);
}
 
void unlang_catch_init(void)
{
        unlang_register(&(unlang_op_t){
                        .name = "catch",
                        .type = UNLANG_TYPE_CATCH,
                        .flag = UNLANG_OP_FLAG_DEBUG_BRACES,
 
                        .compile = unlang_compile_catch,
                        .interpret = unlang_catch,
 
                        .unlang_size = sizeof(unlang_catch_t),
                        .unlang_name = "unlang_catch_t",
                });
}