diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/0tDNS.c | 423 | ||||
| -rw-r--r-- | src/ask_resolver.c | 140 | ||||
| -rw-r--r-- | src/receive_respond.c | 323 |
3 files changed, 0 insertions, 886 deletions
diff --git a/src/0tDNS.c b/src/0tDNS.c deleted file mode 100644 index 180b336..0000000 --- a/src/0tDNS.c +++ /dev/null @@ -1,423 +0,0 @@ -/* - * Code in examine_result() is taken from official libunbound examples: - * https://nlnetlabs.nl/documentation/unbound/libunbound-tutorial-3/ - * The rest of this file is - * Copyright (C) 2020 by Wojtek Kosior <echo a3dvanR1c0Bwcm90b25tYWlsLmNvbQo= | base64 --decode> - - * Permission to use, copy, modify, and/or distribute this software - * for any purpose with or without fee is hereby granted. - - * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH - * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY - * AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, - * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM - * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR - * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR - * PERFORMANCE OF THIS SOFTWARE. - */ - - - -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <errno.h> -#include <arpa/inet.h> -#include <stdbool.h> - -#include <unbound.h> -#include <ldns/ldns.h> - -#include "log.h" - -#define LISTEN_PORT 53 -#define IPADDR_BUFLEN 50 - -/* From receive_respond.c */ -int udp_bind(int, uint16_t); -int socket_create(uint16_t); -ldns_pkt *receive_and_print(int); -int respond_query(int, const char*, const char*, ldns_rr*, uint16_t); -char *hostnamefrompkt(ldns_pkt*, ldns_rr**); - - -/* To specify when creating unbound context - has nothing to do with - * out logging facility - */ -#define DEFAULT_DEBUGLEVEL 0 - -/* - * This is the path in Debian - in other systems it will be different - * and we will need to either somehow find it dynamically or get the path - * from the user. - */ -#define CA_BUNDLE_FILE "/etc/ssl/certs/ca-certificates.crt" - -/* In the long run me might rename this file to somewhere else... */ -#define TRUST_ANCHOR_FILE "./root.key" - -#define MALLOC_FAILURE_STRING "Couldn't allocate memory.\n" - -/* examine the result structure in detail */ -const char *examine_result(const char *query, struct ub_result *result, - char *ipaddr_buf) -{ - int i; - int num; - char buf[IPADDR_BUFLEN]; - char *ipaddr_buf_used; - - ipaddr_buf_used = ipaddr_buf ? ipaddr_buf : buf; - - printf("The query is for: %s\n", query); - printf("The result has:\n"); - printf("qname: %s\n", result->qname); - printf("qtype: %d\n", result->qtype); - printf("qclass: %d\n", result->qclass); - if(result->canonname) - printf("canonical name: %s\n", - result->canonname); - else printf("canonical name: <none>\n"); - - if(result->havedata) - printf("has data\n"); - else printf("has no data\n"); - - if(result->nxdomain) - printf("nxdomain (name does not exist)\n"); - else printf("not an nxdomain (name exists)\n"); - - if(result->secure) - printf("validated to be secure\n"); - else printf("not validated as secure\n"); - - if(result->bogus) - printf("a security failure! (bogus)\n"); - else printf("not a security failure (not bogus)\n"); - - printf("DNS rcode: %d\n", result->rcode); - - if(!result->havedata) - return NULL; - - num = 0; - for(i=0; result->data[i]; i++) { - printf("result data element %d has length %d\n", - i, result->len[i]); - printf("result data element %d is: %s\n", i, - inet_ntop(AF_INET, (struct in_addr*) result->data[i], - ipaddr_buf_used, IPADDR_BUFLEN)); - num++; - } - printf("result has %d data element(s)\n", num); - - return ipaddr_buf; -} - -enum resolution_mode { - RECURSIVE, - FULL, - RESOLV_CONF -}; - -struct ub_ctx *ztdns_create_ub_context(enum resolution_mode mode, - const char *resolver_addr, - int debuglevel) -{ - int rc; - struct ub_ctx* ctx; - const char *error_message_format; - - ctx = ub_ctx_create(); - if (!ctx) { - fprintf(stderr, "Couldn't create libunbound context.\n"); - return NULL; - } - - if (mode == RECURSIVE) { - error_message_format = "Couldn't set forward server: %s\n"; - rc = ub_ctx_set_fwd(ctx, resolver_addr); - if (rc) - goto out; - /* Make DNS over TLS mandatory for recursive resolvers */ - /* TODO tls not working for some reason - this has to be fixed */ - /* error_message_format = "Couldn't enable DNS over TLS: %s\n"; */ - /* rc = ub_ctx_set_tls(ctx, 1); */ - /* if (rc) */ - /* goto out; */ - /* rc = ub_ctx_set_option(ctx, "tls-cert-bundle:", CA_BUNDLE_FILE); */ - } else if (mode == FULL) { - /* TODO use root_hints here for better reliability */ - /* For iterative queries we use DNSSEC if possible */ - error_message_format = "Couldn't set trust anchors: %s\n"; - rc = ub_ctx_add_ta_autr(ctx, TRUST_ANCHOR_FILE); - } else /* if (mode == RESOLV_CONF) */ { - /* NULL can be passed to use system's default resolv.conf */ - error_message_format = "Couldn't use system resolv.conf: %s\n"; - rc = ub_ctx_resolvconf(ctx, NULL); - } - - if (rc) - goto out; - - error_message_format = "Couldn't set debuglevel: %s\n"; - rc = ub_ctx_debuglevel(ctx, debuglevel); - -out: - if (rc) { - fprintf(stderr, error_message_format, ub_strerror(rc)); - ub_ctx_delete(ctx); - return NULL; - } - - return ctx; -} - -const char *ztdns_try_resolve(struct ub_ctx *ctx, const char *name, - char *ipaddr_buf) -{ - struct ub_result* result; - int rc; - const char *ipaddr = NULL; - - rc = ub_resolve(ctx, name, - 1 /* TYPE A (IPv4 address) */, - 1 /* CLASS IN (internet) */, &result); - if(rc) - printf("resolve error: %s\n", ub_strerror(rc)); - else { - ipaddr = examine_result(name, result, ipaddr_buf); - ub_resolve_free(result); - } - - return ipaddr; -} - -struct ztdns_resolver { - struct ub_ctx *ctx; - const char *name; /* arbitrary name - only used for printing to user */ - const char *address; /* IP addr in dot notation stored as string */ - /* Compatible answer must be returned by resolvers with their - * trust levels summing to at least 100 - otherwise the answer is - * considered unreliable. - */ - uint8_t trust_level; - /* Whether we want ztdns to report when this resolver gives answer, - * that is not confirmed by others (i.e. trust levels sum for this - * answer doesn't reach 100). - */ - bool report_errors; - struct ztdns_resolver *next; -}; - -struct ztdns_resolver *ztdns_create_recursive_resolver -(const char *name, const char *address, uint8_t trust_level, bool report_errors, - int debuglevel) -{ - struct ztdns_resolver *resolver; - resolver = malloc(sizeof(struct ztdns_resolver)); - if (!resolver) { - fprintf(stderr, MALLOC_FAILURE_STRING); - return NULL; - } - - resolver->ctx = ztdns_create_ub_context(RECURSIVE, address, debuglevel); - if (!resolver->ctx) - goto out_err; - - resolver->name = name; - resolver->address = address; - resolver->trust_level = trust_level; - resolver->report_errors = report_errors; - resolver->next = NULL; - return resolver; - -out_err: - free(resolver); - return NULL; -} - -void ztdns_delete_recursive_resolver(struct ztdns_resolver *resolver) -{ - ub_ctx_delete(resolver->ctx); - free(resolver); -} - -struct ztdns_instance { - struct ub_ctx *ctx_resolv_conf, *ctx_full; - struct ztdns_resolver *recursive_resolvers; -}; - -/* - * Hardcoded recursive DNS servers. A temporary solution - those should - * ideally by obtained from command line or configuration file. - */ -const char *resolvers_addresses[] = {"8.8.8.8", "8.8.4.4", "1.1.1.1"}; -const char *resolvers_names[] = {"google", "google", "cloudflare"}; -uint8_t resolvers_trust_levels[] = {40, 40, 80}; -uint8_t resolvers_report_errors[] = {true, true, false}; - -#define RESOLVERS_COUNT 3 - -struct ztdns_instance *ztdns_create_instance(int argc, char **argv) -{ - struct ztdns_instance *ztdns; - int i; - struct ztdns_resolver *tmp; - - ztdns = malloc(sizeof(struct ztdns_instance)); - if (!ztdns) { - /* This is an example of how rest of the code shold be - * written/rewritten to use our logging facility. - */ - ztdns_error("No memory, no fun :(\n"); - return NULL; - } - - /* Create context for performing full resolution */ - ztdns->ctx_full = - ztdns_create_ub_context(FULL, NULL, DEFAULT_DEBUGLEVEL); - if (!ztdns->ctx_full) - goto out_err_cleanup_instance; - - /* Create context for performing resolution with default resolver */ - ztdns->ctx_resolv_conf = - ztdns_create_ub_context(RESOLV_CONF, NULL, DEFAULT_DEBUGLEVEL); - if (!ztdns->ctx_resolv_conf) - goto out_err_cleanup_ctx_full; - - /* Create contexts for performing resolution with resolvers provided - * by user (well, hardcoded ones in this case) - */ - ztdns->recursive_resolvers = NULL; - for (i = 0; i < RESOLVERS_COUNT; i++) { - tmp = ztdns_create_recursive_resolver - (resolvers_names[i], resolvers_addresses[i], - resolvers_trust_levels[i], resolvers_report_errors[i], - DEFAULT_DEBUGLEVEL); - if (!tmp) - goto out_err_cleanup_recursive_resolvers; - - tmp->next = ztdns->recursive_resolvers; - ztdns->recursive_resolvers = tmp; - } - - return ztdns; - -out_err_cleanup_recursive_resolvers: - while (ztdns->recursive_resolvers) { - tmp = ztdns->recursive_resolvers->next; - ztdns_delete_recursive_resolver(ztdns->recursive_resolvers); - ztdns->recursive_resolvers = tmp; - } - - ub_ctx_delete(ztdns->ctx_resolv_conf); -out_err_cleanup_ctx_full: - ub_ctx_delete(ztdns->ctx_full); -out_err_cleanup_instance: - free(ztdns); - return NULL; -} - -void ztdns_delete_instance(struct ztdns_instance *ztdns) -{ - struct ztdns_resolver *tmp; - - while (ztdns->recursive_resolvers) { - tmp = ztdns->recursive_resolvers->next; - ztdns_delete_recursive_resolver(ztdns->recursive_resolvers); - ztdns->recursive_resolvers = tmp; - } - - ub_ctx_delete(ztdns->ctx_resolv_conf); - ub_ctx_delete(ztdns->ctx_full); - free(ztdns); -} - -const char *smart_resolve(struct ztdns_instance *ztdns, - const char *queried_name, - char ipaddr_buf[IPADDR_BUFLEN]) -{ - struct ztdns_resolver *tmp; - - printf("* FULL RESOLUTION\n"); - ztdns_try_resolve(ztdns->ctx_full, queried_name, ipaddr_buf); - printf("* USING RESOLVER FROM resolv.conf\n"); - ztdns_try_resolve(ztdns->ctx_resolv_conf, queried_name, NULL); - - for (tmp = ztdns->recursive_resolvers; tmp; tmp = tmp->next) { - printf("* VIA %s (%s)\n", tmp->name, tmp->address); - ztdns_try_resolve(tmp->ctx, queried_name, NULL); - } - - return NULL; -} - -int handle_query(struct ztdns_instance *ztdns, int socket) -{ - ldns_pkt *query; - ldns_rr *query_rr; - uint16_t id; - int rc = 1; - char *queried_name; - char ipaddr[IPADDR_BUFLEN]; - - query = receive_and_print(socket); - if (!query) - return 1; - - queried_name = hostnamefrompkt(query, &query_rr); - if (!queried_name) - goto out_cleanup_query; - - id = ldns_pkt_id(query); - - smart_resolve(ztdns, queried_name, ipaddr); /* fill ipaddr[] */ - rc = respond_query(socket, queried_name, ipaddr, query_rr, id); - - free(queried_name); - -out_cleanup_query: - ldns_pkt_free(query); - return rc; -} - -int main(int argc, char** argv) -{ - int rc = EXIT_FAILURE; - struct ztdns_instance *ztdns; - int socket; - - if (geteuid()) { - ztdns_error("need root privileges\n"); - return EXIT_FAILURE; - } - - socket = socket_create(LISTEN_PORT); - if (socket < 0) - return EXIT_FAILURE; - - ztdns = ztdns_create_instance(argc, argv); - if (!ztdns) - goto out_cleanup_socket; - - while (1) - handle_query(ztdns, socket); - - /* Later on we'll have some way of stopping the daemon - for now this - * line is unreachable */ - ztdns_delete_instance(ztdns); - -out_cleanup_socket: - close(socket); - return rc; - - /* - * The adsuck program would additionally do many cool things in main(), - * i.e. parse command line options, drop root privileges, setup signal - * handlers, etc. We could incorporate some of this into our program - * later. I omitted it for now for simplicity and to ease porting to - * windoze if You guys want to do that (but don't count on me in this - * matter). - */ -} diff --git a/src/ask_resolver.c b/src/ask_resolver.c deleted file mode 100644 index dc7c660..0000000 --- a/src/ask_resolver.c +++ /dev/null @@ -1,140 +0,0 @@ -/* - * Code in examine_result() is taken from official libunbound examples: - * https://nlnetlabs.nl/documentation/unbound/libunbound-tutorial-3/ - * The rest of this file is - * Copyright (C) 2020 by Wojtek Kosior <echo a3dvanR1c0Bwcm90b25tYWlsLmNvbQo= | base64 --decode> - - * Permission to use, copy, modify, and/or distribute this software - * for any purpose with or without fee is hereby granted. - - * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH - * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY - * AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, - * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM - * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR - * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR - * PERFORMANCE OF THIS SOFTWARE. - */ - -/* - * This is a simple helper program for testing our resolver. - */ - -#include <stdio.h> -#include <stdlib.h> -#include <arpa/inet.h> - -#include <unbound.h> - -/* examine the result structure in detail */ -void examine_result(const char *query, struct ub_result *result) -{ - int i; - int num; - - printf("The query is for: %s\n", query); - printf("The result has:\n"); - printf("qname: %s\n", result->qname); - printf("qtype: %d\n", result->qtype); - printf("qclass: %d\n", result->qclass); - if(result->canonname) - printf("canonical name: %s\n", - result->canonname); - else printf("canonical name: <none>\n"); - - if(result->havedata) - printf("has data\n"); - else printf("has no data\n"); - - if(result->nxdomain) - printf("nxdomain (name does not exist)\n"); - else printf("not an nxdomain (name exists)\n"); - - if(result->secure) - printf("validated to be secure\n"); - else printf("not validated as secure\n"); - - if(result->bogus) - printf("a security failure! (bogus)\n"); - else printf("not a security failure (not bogus)\n"); - - printf("DNS rcode: %d\n", result->rcode); - - if(!result->havedata) - return; - - num = 0; - for(i=0; result->data[i]; i++) { - printf("result data element %d has length %d\n", - i, result->len[i]); - printf("result data element %d is: %s\n", - i, inet_ntoa(*(struct in_addr*)result->data[i])); - num++; - } - printf("result has %d data element(s)\n", num); -} - -struct ub_ctx *create_ub_context(char *forwarder_addr, int debuglevel) -{ - int rc; - struct ub_ctx* ctx; - char *error_message_format; - - ctx = ub_ctx_create(); - if (!ctx) { - fprintf(stderr, "Couldn't create libunbound context.\n"); - return NULL; - } - - error_message_format = "Couldn't set forwarder: %s\n"; - rc = ub_ctx_set_fwd(ctx, forwarder_addr); - if (rc) - goto out; - - error_message_format = "Couldn't set debuglevel: %s\n"; - rc = ub_ctx_debuglevel(ctx, debuglevel); - -out: - if (rc) { - fprintf(stderr, error_message_format, ub_strerror(rc)); - ub_ctx_delete(ctx); - return NULL; - } - - return ctx; -} - -void ztdns_try_resolve(struct ub_ctx *ctx, const char *name) -{ - struct ub_result* result; - int rc; - rc = ub_resolve(ctx, name, - 1 /* TYPE A (IPv4 address) */, - 1 /* CLASS IN (internet) */, &result); - if(rc) - printf("resolve error: %s\n", ub_strerror(rc)); - else { - examine_result(name, result); - ub_resolve_free(result); - } -} - -int main(int argc, char** argv) -{ - struct ub_ctx *ctx; - - if (argc != 3) { - printf("Usage: %s DNS_SERVER DOMAINNAME\n", argv[0]); - return EXIT_FAILURE; - } - - ctx = create_ub_context(argv[1], 3); - if (!ctx) - return EXIT_FAILURE; - - ztdns_try_resolve(ctx, argv[2]); - - ub_ctx_delete(ctx); - - return EXIT_SUCCESS; -} diff --git a/src/receive_respond.c b/src/receive_respond.c deleted file mode 100644 index a3b1e8e..0000000 --- a/src/receive_respond.c +++ /dev/null @@ -1,323 +0,0 @@ -/* - * Copyright (c) 2009 - 2012 Marco Peereboom <marco@peereboom.us> - * - * Permission to use, copy, modify, and distribute this software for any - * purpose with or without fee is hereby granted, provided that the above - * copyright notice and this permission notice appear in all copies. - * - * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES - * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF - * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR - * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES - * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN - * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF - * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. - */ - -/* for strdup() */ -#define _POSIX_C_SOURCE 200809L -#include <string.h> - -#include <stdio.h> -#include <stdlib.h> -#include <err.h> - -#include <netinet/in.h> -#include <arpa/inet.h> - -#include <ldns/ldns.h> - -#define MAXLINE 256 -#define INBUF_SIZE 4096 - -struct sockaddr paddr; -socklen_t plen = (socklen_t)sizeof(paddr); - -int -udp_bind(int sock, uint16_t port) -{ - struct sockaddr_in addr; - in_addr_t maddr = INADDR_ANY; - - addr.sin_family = AF_INET; - addr.sin_port = (in_port_t) htons((uint16_t)port); - addr.sin_addr.s_addr = maddr; - return (bind(sock, (struct sockaddr*)&addr, (socklen_t) sizeof(addr))); -} - -int -socket_create(uint16_t port) { - int so = socket(AF_INET, SOCK_DGRAM, 0); - if (so == -1) - err(1, "can't open socket"); - if (udp_bind(so, port)) - err(1, "can't udp bind"); - return so; -} - -void -printpacket(ldns_pkt *pkt) -{ - char *str = ldns_pkt2str(pkt); - - if (str) { - printf("%s", str); - LDNS_FREE(str); - } else - warnx("could not convert packet to string"); -} - -ldns_pkt * -receive_and_print(int so) { - uint8_t inbuf[INBUF_SIZE]; - ssize_t nb; - ldns_status status; - ldns_pkt *query_pkt; - - nb = recvfrom(so, inbuf, INBUF_SIZE, 0, &paddr, &plen); - if (nb == -1) { - if (errno == EINTR || errno == EAGAIN) - return NULL; - else - err(EXIT_FAILURE, "recvfrom"); - } - - status = ldns_wire2pkt(&query_pkt, inbuf, (size_t)nb); - if (status != LDNS_STATUS_OK) { - warnx("bad packet: %s", ldns_get_errorstr_by_id(status)); - return NULL; - } else { - puts("received packet:"); - printpacket(query_pkt); - } - - return query_pkt; -} - -int -send_response(int so, const char *hostname, ldns_pkt *respkt, uint16_t id) -{ - size_t answer_size; - ldns_status status; - uint8_t *outbuf = NULL; - int rv = 1; - - if (hostname == NULL || respkt == NULL) { - warnx("send_response: invalid parameters"); - return (0); - } - - ldns_pkt_set_id(respkt, id); - status = ldns_pkt2wire(&outbuf, respkt, &answer_size); - if (status != LDNS_STATUS_OK) - warnx("can't create answer: %s", - ldns_get_errorstr_by_id(status)); - else { - puts("response packet:"); - printpacket(respkt); - - if (sendto(so, outbuf, answer_size, 0, &paddr, plen) == -1) - warn("send_response: sendto"); - else { - rv = 0; - - printf("send_response: resolved %s", hostname); - } - } - - if (outbuf) - LDNS_FREE(outbuf); - - return (rv); -} - -char * -hostnamefrompkt(ldns_pkt *pkt, ldns_rr **qrr) -{ - ldns_rr *query_rr; - ldns_buffer *out = NULL; - ldns_rdf *rdf; - char *ret = NULL; - - if (pkt == NULL) - return (NULL); - - query_rr = ldns_rr_list_rr(ldns_pkt_question(pkt), 0); - if (query_rr == NULL) { - warnx("hostnamefrompkt invalid parameters"); - goto done; - } - - out = ldns_buffer_new(LDNS_MAX_DOMAINLEN); - if (out == NULL) { - warnx("no memory for out buffer"); - goto done; - } - - rdf = ldns_rr_owner(query_rr); - if (ldns_rdf2buffer_str_dname(out, rdf) != LDNS_STATUS_OK) { - warnx("can't get hostname"); - goto done; - } - - ret = strdup((char *)ldns_buffer_begin(out)); - if (ret == NULL) { - warn("no memory for hostname"); - goto done; - } - - if (qrr) - *qrr = query_rr; -done: - if (out) - ldns_buffer_free(out); - - return (ret); -} - -int -respond_query(int so, const char *hostname, const char *ipaddr, - ldns_rr *query_rr, uint16_t id) -{ - ldns_status status; - ldns_rr_list *answer_an = NULL; - ldns_rr_list *answer_ns = NULL; - ldns_rr_list *answer_ad = NULL; - ldns_rr_list *answer_qr = NULL; - ldns_pkt *answer_pkt = NULL; - ldns_rr *myrr = NULL, *myaurr = NULL, *myasrr = NULL; - ldns_rdf *prev = NULL; - char buf[MAXLINE * 2]; - uint8_t *outbuf = NULL; - int rv = 1; - - /* answer section */ - answer_an = ldns_rr_list_new(); - if (answer_an == NULL) - goto unwind; - - /* authority section */ - answer_ns = ldns_rr_list_new(); - if (answer_ns == NULL) - goto unwind; - - /* if we have an ip spoof it there */ - if (ipaddr) { - /* an */ - snprintf(buf, sizeof buf, "%s\t%d\tIN\tA\t%s", - hostname, 259200, ipaddr); - status = ldns_rr_new_frm_str(&myrr, buf, 0, NULL, &prev); - if (status != LDNS_STATUS_OK) { - fprintf(stderr, "can't create answer section: %s\n", - ldns_get_errorstr_by_id(status)); - goto unwind; - } - ldns_rr_list_push_rr(answer_an, myrr); - ldns_rdf_deep_free(prev); - prev = NULL; - - /* ns */ - snprintf(buf, sizeof buf, "%s\t%d\tIN\tNS\t%s.", - hostname, 259200, "localhost"); - status = ldns_rr_new_frm_str(&myaurr, buf, 0, NULL, &prev); - if (status != LDNS_STATUS_OK) { - fprintf(stderr, "can't create authority section: %s\n", - ldns_get_errorstr_by_id(status)); - goto unwind; - } - ldns_rr_list_push_rr(answer_ns, myaurr); - ldns_rdf_deep_free(prev); - prev = NULL; - } else { - snprintf(buf, sizeof buf, "%s\t3600\tIN\tSOA\t%s root.%s %s", - hostname, - hostname, - hostname, - "2 3600 900 3600000 3600"); - status = ldns_rr_new_frm_str(&myaurr, buf, 0, NULL, &prev); - if (status != LDNS_STATUS_OK) { - fprintf(stderr, "can't create authority section: %s\n", - ldns_get_errorstr_by_id(status)); - goto unwind; - } - ldns_rr_list_push_rr(answer_ns, myaurr); - ldns_rdf_deep_free(prev); - prev = NULL; - } - - /* question section */ - answer_qr = ldns_rr_list_new(); - if (answer_qr == NULL) - goto unwind; - ldns_rr_list_push_rr(answer_qr, ldns_rr_clone(query_rr)); - - /* additional section */ - answer_ad = ldns_rr_list_new(); - if (answer_ad == NULL) - goto unwind; - if (ipaddr) { - snprintf(buf, sizeof buf, "%s\t%d\tIN\tA\t%s", - "localhost", - 259200, - "127.0.0.1"); - status = ldns_rr_new_frm_str(&myasrr, buf, 0, NULL, &prev); - if (status != LDNS_STATUS_OK) { - fprintf(stderr, "can't create additional section: %s\n", - ldns_get_errorstr_by_id(status)); - goto unwind; - } - ldns_rr_list_push_rr(answer_ad, myasrr); - ldns_rdf_deep_free(prev); - prev = NULL; - - /* V6 */ - snprintf(buf, sizeof buf, "%s\t%d\tIN\tAAAA\t%s", - "localhost", - 259200, - "::1"); - status = ldns_rr_new_frm_str(&myasrr, buf, 0, NULL, &prev); - if (status != LDNS_STATUS_OK) { - fprintf(stderr, "can't create additional section: %s\n", - ldns_get_errorstr_by_id(status)); - goto unwind; - } - ldns_rr_list_push_rr(answer_ad, myasrr); - ldns_rdf_deep_free(prev); - prev = NULL; - } - - /* actual packet */ - answer_pkt = ldns_pkt_new(); - if (answer_pkt == NULL) - goto unwind; - - ldns_pkt_set_qr(answer_pkt, 1); - ldns_pkt_set_aa(answer_pkt, 1); - if (ipaddr == NULL) - ldns_pkt_set_rcode(answer_pkt, LDNS_RCODE_NXDOMAIN); - - ldns_pkt_push_rr_list(answer_pkt, LDNS_SECTION_QUESTION, answer_qr); - ldns_pkt_push_rr_list(answer_pkt, LDNS_SECTION_ANSWER, answer_an); - ldns_pkt_push_rr_list(answer_pkt, LDNS_SECTION_AUTHORITY, answer_ns); - ldns_pkt_push_rr_list(answer_pkt, LDNS_SECTION_ADDITIONAL, answer_ad); - - /* reply to caller */ - if (send_response(so, hostname, answer_pkt, id)) - warnx("send_response failed"); - -unwind: - if (answer_pkt) - ldns_pkt_free(answer_pkt); - if (outbuf) - LDNS_FREE(outbuf); - if (answer_qr) - ldns_rr_list_free(answer_qr); - if (answer_an) - ldns_rr_list_free(answer_an); - if (answer_ns) - ldns_rr_list_free(answer_ns); - if (answer_ad) - ldns_rr_list_free(answer_ad); - - return (rv); -} |