diff options
Diffstat (limited to 'src/receive_respond.c')
| -rw-r--r-- | src/receive_respond.c | 323 |
1 files changed, 0 insertions, 323 deletions
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); -} |