From 830407e88f9d40d954356c3754f2647f91d5c06a Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 17:26:00 +0200 Subject: Adding upstream version 5.6.0. Signed-off-by: Daniel Baumann --- modules/nsid/nsid.c | 114 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 114 insertions(+) create mode 100644 modules/nsid/nsid.c (limited to 'modules/nsid/nsid.c') diff --git a/modules/nsid/nsid.c b/modules/nsid/nsid.c new file mode 100644 index 0000000..a67dcdb --- /dev/null +++ b/modules/nsid/nsid.c @@ -0,0 +1,114 @@ +/* Copyright (C) Knot Resolver contributors + * SPDX-License-Identifier: GPL-3.0-or-later + * + * This module provides NSID support according to RFC 5001. */ + +#include +#include +#include +#include + +#include "daemon/engine.h" +#include "lib/layer.h" + +struct nsid_config { + uint8_t *local_nsid; + size_t local_nsid_len; +}; + +static int nsid_finalize(kr_layer_t *ctx) { + const struct kr_module *module = ctx->api->data; + const struct nsid_config *config = module->data; + struct kr_request *req = ctx->req; + + /* no local NSID configured, do nothing */ + if (config->local_nsid == NULL) + return ctx->state; + + const knot_rrset_t *src_opt = req->qsource.packet->opt_rr; + /* no EDNS in request, do nothing */ + if (src_opt == NULL) + return ctx->state; + + const uint8_t *req_nsid = knot_edns_get_option(src_opt, KNOT_EDNS_OPTION_NSID, NULL); + /* NSID option must be explicitly requested */ + if (req_nsid == NULL) + return ctx->state; + + /* Check violation of https://tools.ietf.org/html/rfc5001#section-2.1: + * The resolver MUST NOT include any NSID payload data in the query */ + if (knot_edns_opt_get_length(req_nsid) != 0) + kr_log_debug(NSID, "[%05u. ] FORMERR: NSID option in query " + "must not contain payload, continuing\n", req->uid); + /* FIXME: actually change RCODE in answer to FORMERR? */ + + /* Sanity check, answer should have EDNS as well but who knows ... */ + if (kr_fails_assert(req->answer->opt_rr)) + return ctx->state; + + if (knot_edns_add_option(req->answer->opt_rr, KNOT_EDNS_OPTION_NSID, + config->local_nsid_len, config->local_nsid, + &req->pool) != KNOT_EOK) { + /* something went wrong and there is no way to salvage content of OPT RRset */ + kr_log_debug(NSID, "[%05u. ] unable to add NSID option\n", req->uid); + knot_rrset_clear(req->answer->opt_rr, &req->pool); + } + + return ctx->state; +} + +static char* nsid_name(void *env, struct kr_module *module, const char *args) +{ + struct engine *engine = env; + struct nsid_config *config = module->data; + if (args) { /* set */ + /* API is not binary safe, we need to fix this one day */ + uint8_t *arg_copy = (uint8_t *)strdup(args); + if (arg_copy == NULL) + luaL_error(engine->L, "[nsid] error while allocating new NSID value\n"); + free(config->local_nsid); + config->local_nsid = arg_copy; + config->local_nsid_len = strlen(args); + } + + /* get */ + if (config->local_nsid != NULL) + return json_encode_string((char *)config->local_nsid); + else + return NULL; +} + +KR_EXPORT +int nsid_init(struct kr_module *module) { + static kr_layer_api_t layer = { + .answer_finalize = &nsid_finalize, + }; + layer.data = module; + module->layer = &layer; + + static const struct kr_prop props[] = { + { &nsid_name, "name", "Get or set local NSID value" }, + { NULL, NULL, NULL } + }; + module->props = props; + + struct nsid_config *config = calloc(1, sizeof(struct nsid_config)); + if (config == NULL) + return kr_error(ENOMEM); + + module->data = config; + return kr_ok(); +} + +KR_EXPORT +int nsid_deinit(struct kr_module *module) { + struct nsid_config *config = module->data; + if (config != NULL) { + free(config->local_nsid); + free(config); + module->data = NULL; + } + return kr_ok(); +} + +KR_MODULE_EXPORT(nsid) -- cgit v1.2.3