/* $NetBSD: ns_rdata.c,v 1.1.1.2 2012/09/09 16:08:03 christos Exp $ */ /* * Copyright (C) 2009 Internet Systems Consortium, Inc. ("ISC") * * Permission to use, copy, modify, and/or 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 ISC DISCLAIMS ALL WARRANTIES WITH * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY * AND FITNESS. IN NO EVENT SHALL ISC 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. */ #ifndef lint static const char rcsid[] = "Id: ns_rdata.c,v 1.2 2009/01/23 23:49:15 tbox Exp "; #endif #include "port_before.h" #if __OpenBSD__ #include #endif #include #include #include #include #include #include "port_after.h" #define CONSUME_SRC \ do { \ rdata += n, rdlen -= n; \ } while (0) #define CONSUME_DST \ do { \ nrdata += n, nrdsiz -= n, nrdlen += n; \ } while (0) #define UNPACK_DNAME \ do { \ size_t t; \ \ if ((n = ns_name_unpack2(msg,eom,rdata,nrdata,nrdsiz,&t))<0) {\ errno = EMSGSIZE; \ return (-1); \ } \ CONSUME_SRC; \ n = t; \ CONSUME_DST; \ } while (0) #define UNPACK_SOME(x) \ do { \ n = (x); \ if ((size_t)n > rdlen || (size_t)n > nrdsiz) { \ errno = EMSGSIZE; \ return (-1); \ } \ memcpy(nrdata, rdata, n); \ CONSUME_SRC; CONSUME_DST; \ } while (0) #define UNPACK_REST(x) \ do { \ n = (x); \ if ((size_t)n != rdlen) { \ errno = EMSGSIZE; \ return (-1); \ } \ memcpy(nrdata, rdata, n); \ CONSUME_SRC; CONSUME_DST; \ } while (0) ssize_t ns_rdata_unpack(const u_char *msg, const u_char *eom, ns_type type, const u_char *rdata, size_t rdlen, u_char *nrdata, size_t nrdsiz) { size_t nrdlen = 0; int n; switch (type) { case ns_t_a: UNPACK_REST(NS_INADDRSZ); break; case ns_t_aaaa: UNPACK_REST(NS_IN6ADDRSZ); break; case ns_t_cname: case ns_t_mb: case ns_t_mg: case ns_t_mr: case ns_t_ns: case ns_t_ptr: case ns_t_dname: UNPACK_DNAME; break; case ns_t_soa: UNPACK_DNAME; UNPACK_DNAME; UNPACK_SOME(NS_INT32SZ * 5); break; case ns_t_mx: case ns_t_afsdb: case ns_t_rt: UNPACK_SOME(NS_INT16SZ); UNPACK_DNAME; break; case ns_t_px: UNPACK_SOME(NS_INT16SZ); UNPACK_DNAME; UNPACK_DNAME; break; case ns_t_srv: UNPACK_SOME(NS_INT16SZ * 3); UNPACK_DNAME; break; case ns_t_minfo: case ns_t_rp: UNPACK_DNAME; UNPACK_DNAME; break; default: UNPACK_SOME(rdlen); break; } if (rdlen > 0) { errno = EMSGSIZE; return (-1); } return (nrdlen); } #define EQUAL_CONSUME \ do { \ rdata1 += n, rdlen1 -= n; \ rdata2 += n, rdlen2 -= n; \ } while (0) #define EQUAL_DNAME \ do { \ ssize_t n; \ \ if (rdlen1 != rdlen2) \ return (0); \ n = ns_name_eq(rdata1, rdlen1, rdata2, rdlen2); \ if (n <= 0) \ return (n); \ n = rdlen1; \ EQUAL_CONSUME; \ } while (0) #define EQUAL_SOME(x) \ do { \ size_t n = (x); \ \ if (n > rdlen1 || n > rdlen2) { \ errno = EMSGSIZE; \ return (-1); \ } \ if (memcmp(rdata1, rdata2, n) != 0) \ return (0); \ EQUAL_CONSUME; \ } while (0) int ns_rdata_equal(ns_type type, const u_char *rdata1, size_t rdlen1, const u_char *rdata2, size_t rdlen2) { switch (type) { case ns_t_cname: case ns_t_mb: case ns_t_mg: case ns_t_mr: case ns_t_ns: case ns_t_ptr: case ns_t_dname: EQUAL_DNAME; break; case ns_t_soa: /* "There can be only one." --Highlander */ break; case ns_t_mx: case ns_t_afsdb: case ns_t_rt: EQUAL_SOME(NS_INT16SZ); EQUAL_DNAME; break; case ns_t_px: EQUAL_SOME(NS_INT16SZ); EQUAL_DNAME; EQUAL_DNAME; break; case ns_t_srv: EQUAL_SOME(NS_INT16SZ * 3); EQUAL_DNAME; break; case ns_t_minfo: case ns_t_rp: EQUAL_DNAME; EQUAL_DNAME; break; default: EQUAL_SOME(rdlen1); break; } if (rdlen1 != 0 || rdlen2 != 0) return (0); return (1); } #define REFERS_DNAME \ do { \ int n; \ \ n = ns_name_eq(rdata, rdlen, nname, NS_MAXNNAME); \ if (n < 0) \ return (-1); \ if (n > 0) \ return (1); \ n = dn_skipname(rdata, rdata + rdlen); \ if (n < 0) \ return (-1); \ CONSUME_SRC; \ } while (0) #define REFERS_SOME(x) \ do { \ size_t n = (x); \ \ if (n > rdlen) { \ errno = EMSGSIZE; \ return (-1); \ } \ CONSUME_SRC; \ } while (0) int ns_rdata_refers(ns_type type, const u_char *rdata, size_t rdlen, const u_char *nname) { switch (type) { case ns_t_cname: case ns_t_mb: case ns_t_mg: case ns_t_mr: case ns_t_ns: case ns_t_ptr: case ns_t_dname: REFERS_DNAME; break; case ns_t_soa: REFERS_DNAME; REFERS_DNAME; REFERS_SOME(NS_INT32SZ * 5); break; case ns_t_mx: case ns_t_afsdb: case ns_t_rt: REFERS_SOME(NS_INT16SZ); REFERS_DNAME; break; case ns_t_px: REFERS_SOME(NS_INT16SZ); REFERS_DNAME; REFERS_DNAME; break; case ns_t_srv: REFERS_SOME(NS_INT16SZ * 3); REFERS_DNAME; break; case ns_t_minfo: case ns_t_rp: REFERS_DNAME; REFERS_DNAME; break; default: REFERS_SOME(rdlen); break; } if (rdlen != 0) { errno = EMSGSIZE; return (-1); } return (0); }