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-rw-r--r--unpack_dns.c295
1 files changed, 0 insertions, 295 deletions
diff --git a/unpack_dns.c b/unpack_dns.c
deleted file mode 100644
index fe50b026..00000000
--- a/unpack_dns.c
+++ /dev/null
@@ -1,295 +0,0 @@
-/* $OpenBSD: unpack_dns.c,v 1.1 2018/01/06 07:57:53 sunil Exp $ */
-
-/*
- * Copyright (c) 2011-2014 Eric Faurot <eric@faurot.net>
- *
- * 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.
- */
-
-#include <arpa/inet.h>
-
-#include <string.h>
-
-#include "unpack_dns.h"
-
-static int unpack_data(struct unpack *, void *, size_t);
-static int unpack_u16(struct unpack *, uint16_t *);
-static int unpack_u32(struct unpack *, uint32_t *);
-static int unpack_inaddr(struct unpack *, struct in_addr *);
-static int unpack_in6addr(struct unpack *, struct in6_addr *);
-static int unpack_dname(struct unpack *, char *, size_t);
-
-void
-unpack_init(struct unpack *unpack, const char *buf, size_t len)
-{
- unpack->buf = buf;
- unpack->len = len;
- unpack->offset = 0;
- unpack->err = NULL;
-}
-
-int
-unpack_header(struct unpack *p, struct dns_header *h)
-{
- if (unpack_data(p, h, HFIXEDSZ) == -1)
- return (-1);
-
- h->flags = ntohs(h->flags);
- h->qdcount = ntohs(h->qdcount);
- h->ancount = ntohs(h->ancount);
- h->nscount = ntohs(h->nscount);
- h->arcount = ntohs(h->arcount);
-
- return (0);
-}
-
-int
-unpack_query(struct unpack *p, struct dns_query *q)
-{
- unpack_dname(p, q->q_dname, sizeof(q->q_dname));
- unpack_u16(p, &q->q_type);
- unpack_u16(p, &q->q_class);
-
- return (p->err) ? (-1) : (0);
-}
-
-int
-unpack_rr(struct unpack *p, struct dns_rr *rr)
-{
- uint16_t rdlen;
- size_t save_offset;
-
- unpack_dname(p, rr->rr_dname, sizeof(rr->rr_dname));
- unpack_u16(p, &rr->rr_type);
- unpack_u16(p, &rr->rr_class);
- unpack_u32(p, &rr->rr_ttl);
- unpack_u16(p, &rdlen);
-
- if (p->err)
- return (-1);
-
- if (p->len - p->offset < rdlen) {
- p->err = "too short";
- return (-1);
- }
-
- save_offset = p->offset;
-
- switch (rr->rr_type) {
-
- case T_CNAME:
- unpack_dname(p, rr->rr.cname.cname, sizeof(rr->rr.cname.cname));
- break;
-
- case T_MX:
- unpack_u16(p, &rr->rr.mx.preference);
- unpack_dname(p, rr->rr.mx.exchange, sizeof(rr->rr.mx.exchange));
- break;
-
- case T_NS:
- unpack_dname(p, rr->rr.ns.nsname, sizeof(rr->rr.ns.nsname));
- break;
-
- case T_PTR:
- unpack_dname(p, rr->rr.ptr.ptrname, sizeof(rr->rr.ptr.ptrname));
- break;
-
- case T_SOA:
- unpack_dname(p, rr->rr.soa.mname, sizeof(rr->rr.soa.mname));
- unpack_dname(p, rr->rr.soa.rname, sizeof(rr->rr.soa.rname));
- unpack_u32(p, &rr->rr.soa.serial);
- unpack_u32(p, &rr->rr.soa.refresh);
- unpack_u32(p, &rr->rr.soa.retry);
- unpack_u32(p, &rr->rr.soa.expire);
- unpack_u32(p, &rr->rr.soa.minimum);
- break;
-
- case T_A:
- if (rr->rr_class != C_IN)
- goto other;
- unpack_inaddr(p, &rr->rr.in_a.addr);
- break;
-
- case T_AAAA:
- if (rr->rr_class != C_IN)
- goto other;
- unpack_in6addr(p, &rr->rr.in_aaaa.addr6);
- break;
- default:
- other:
- rr->rr.other.rdata = p->buf + p->offset;
- rr->rr.other.rdlen = rdlen;
- p->offset += rdlen;
- }
-
- if (p->err)
- return (-1);
-
- /* make sure that the advertised rdlen is really ok */
- if (p->offset - save_offset != rdlen)
- p->err = "bad dlen";
-
- return (p->err) ? (-1) : (0);
-}
-
-ssize_t
-dname_expand(const unsigned char *data, size_t len, size_t offset,
- size_t *newoffset, char *dst, size_t max)
-{
- size_t n, count, end, ptr, start;
- ssize_t res;
-
- if (offset >= len)
- return (-1);
-
- res = 0;
- end = start = offset;
-
- for (; (n = data[offset]); ) {
- if ((n & 0xc0) == 0xc0) {
- if (offset + 2 > len)
- return (-1);
- ptr = 256 * (n & ~0xc0) + data[offset + 1];
- if (ptr >= start)
- return (-1);
- if (end < offset + 2)
- end = offset + 2;
- offset = start = ptr;
- continue;
- }
- if (offset + n + 1 > len)
- return (-1);
-
- /* copy n + at offset+1 */
- if (dst != NULL && max != 0) {
- count = (max < n + 1) ? (max) : (n + 1);
- memmove(dst, data + offset, count);
- dst += count;
- max -= count;
- }
- res += n + 1;
- offset += n + 1;
- if (end < offset)
- end = offset;
- }
- if (end < offset + 1)
- end = offset + 1;
-
- if (dst != NULL && max != 0)
- dst[0] = 0;
- if (newoffset)
- *newoffset = end;
- return (res + 1);
-}
-
-char *
-print_dname(const char *_dname, char *buf, size_t max)
-{
- const unsigned char *dname = _dname;
- char *res;
- size_t left, n, count;
-
- if (_dname[0] == 0) {
- (void)strlcpy(buf, ".", max);
- return buf;
- }
-
- res = buf;
- left = max - 1;
- for (n = 0; dname[0] && left; n += dname[0]) {
- count = (dname[0] < (left - 1)) ? dname[0] : (left - 1);
- memmove(buf, dname + 1, count);
- dname += dname[0] + 1;
- left -= count;
- buf += count;
- if (left) {
- left -= 1;
- *buf++ = '.';
- }
- }
- buf[0] = 0;
-
- return (res);
-}
-
-static int
-unpack_data(struct unpack *p, void *data, size_t len)
-{
- if (p->err)
- return (-1);
-
- if (p->len - p->offset < len) {
- p->err = "too short";
- return (-1);
- }
-
- memmove(data, p->buf + p->offset, len);
- p->offset += len;
-
- return (0);
-}
-
-static int
-unpack_u16(struct unpack *p, uint16_t *u16)
-{
- if (unpack_data(p, u16, 2) == -1)
- return (-1);
-
- *u16 = ntohs(*u16);
-
- return (0);
-}
-
-static int
-unpack_u32(struct unpack *p, uint32_t *u32)
-{
- if (unpack_data(p, u32, 4) == -1)
- return (-1);
-
- *u32 = ntohl(*u32);
-
- return (0);
-}
-
-static int
-unpack_inaddr(struct unpack *p, struct in_addr *a)
-{
- return (unpack_data(p, a, 4));
-}
-
-static int
-unpack_in6addr(struct unpack *p, struct in6_addr *a6)
-{
- return (unpack_data(p, a6, 16));
-}
-
-static int
-unpack_dname(struct unpack *p, char *dst, size_t max)
-{
- ssize_t e;
-
- if (p->err)
- return (-1);
-
- e = dname_expand(p->buf, p->len, p->offset, &p->offset, dst, max);
- if (e == -1) {
- p->err = "bad domain name";
- return (-1);
- }
- if (e < 0 || e > MAXDNAME) {
- p->err = "domain name too long";
- return (-1);
- }
-
- return (0);
-}
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.