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#include <libknot/rrtype/opt.h>
#include "lib/module.h"
#include "daemon/engine.h"
static int extended_error_finalize(kr_layer_t *ctx) {
struct kr_request *req = ctx->req;
const knot_rrset_t *src_opt = req->qsource.packet->opt_rr;
const struct kr_extended_error *ede = &req->extended_error;
if (ede->info_code == KNOT_EDNS_EDE_NONE /* no extended error */
|| src_opt == NULL /* no EDNS in query */
|| kr_fails_assert(ede->info_code >= 0 && ede->info_code < UINT16_MAX) /* info code out of range */
|| kr_fails_assert(req->answer->opt_rr) /* sanity check - answer should have EDNS */
) {
return ctx->state;
}
const uint16_t info_code = (uint16_t)ede->info_code;
const size_t extra_len = ede->extra_text ? strlen(ede->extra_text) : 0;
uint8_t buf[sizeof(info_code) + extra_len];
knot_wire_write_u16(buf, info_code);
if (extra_len)
memcpy(buf + sizeof(info_code), ede->extra_text, extra_len);
if (knot_edns_add_option(req->answer->opt_rr, KNOT_EDNS_OPTION_EDE,
sizeof(buf), buf, &req->pool) != KNOT_EOK) {
/* something went wrong and there is no way to salvage content of OPT RRset */
kr_log_req(req, 0, 0, EDE, "unable to add Extended Error option\n");
knot_rrset_clear(req->answer->opt_rr, &req->pool);
}
return ctx->state;
}
KR_EXPORT
int extended_error_init(struct kr_module *module) {
static kr_layer_api_t layer = {
.answer_finalize = &extended_error_finalize,
};
layer.data = module;
module->layer = &layer;
return kr_ok();
}
KR_MODULE_EXPORT(extended_error)
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