diff options
Diffstat (limited to '')
| -rw-r--r-- | src/core/object/dns.c | 471 | ||||
| -rw-r--r-- | src/core/object/dns.h | 184 | ||||
| -rw-r--r-- | src/core/object/dns.hh | 119 | ||||
| -rw-r--r-- | src/core/object/dns.lua | 797 | ||||
| -rw-r--r-- | src/core/object/dns/label.lua | 118 | ||||
| -rw-r--r-- | src/core/object/dns/q.lua | 52 | ||||
| -rw-r--r-- | src/core/object/dns/rr.lua | 85 |
7 files changed, 1826 insertions, 0 deletions
diff --git a/src/core/object/dns.c b/src/core/object/dns.c new file mode 100644 index 0000000..49aec6d --- /dev/null +++ b/src/core/object/dns.c @@ -0,0 +1,471 @@ +/* + * Copyright (c) 2018-2021, OARC, Inc. + * All rights reserved. + * + * This file is part of dnsjit. + * + * dnsjit is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * dnsjit is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with dnsjit. If not, see <http://www.gnu.org/licenses/>. + */ + +#include "config.h" + +#include "core/object/dns.h" +#include "core/object/payload.h" +#include "core/assert.h" + +#include <stdlib.h> +#include <string.h> +#ifdef HAVE_ENDIAN_H +#include <endian.h> +#else +#ifdef HAVE_SYS_ENDIAN_H +#include <sys/endian.h> +#else +#ifdef HAVE_MACHINE_ENDIAN_H +#include <machine/endian.h> +#endif +#endif +#endif +#ifdef HAVE_BYTESWAP_H +#include <byteswap.h> +#endif +#ifndef bswap_16 +#ifndef bswap16 +#define bswap_16(x) swap16(x) +#define bswap_32(x) swap32(x) +#define bswap_64(x) swap64(x) +#else +#define bswap_16(x) bswap16(x) +#define bswap_32(x) bswap32(x) +#define bswap_64(x) bswap64(x) +#endif +#endif + +#define _ERR_MALFORMED -2 +#define _ERR_NEEDLABELS -3 + +static core_log_t _log = LOG_T_INIT("core.object.dns"); +static core_object_dns_t _defaults = CORE_OBJECT_DNS_INIT(0); + +static core_object_dns_label_t _defaults_label = { 0 }; +static core_object_dns_rr_t _defaults_rr = { 0 }; +static core_object_dns_q_t _defaults_q = { 0 }; + +core_log_t* core_object_dns_log() +{ + return &_log; +} + +core_object_dns_t* core_object_dns_new() +{ + core_object_dns_t* self; + + mlfatal_oom(self = malloc(sizeof(core_object_dns_t))); + *self = _defaults; + + return self; +} + +core_object_dns_t* core_object_dns_copy(const core_object_dns_t* self) +{ + core_object_dns_t* copy; + mlassert_self(); + + mlfatal_oom(copy = malloc(sizeof(core_object_dns_t))); + memcpy(copy, self, sizeof(core_object_dns_t)); + copy->obj_prev = 0; + + return (core_object_dns_t*)copy; +} + +void core_object_dns_free(core_object_dns_t* self) +{ + mlassert_self(); + free(self); +} + +#define need8(v, p, l) \ + if (l < 1) { \ + break; \ + } \ + v = *p; \ + p += 1; \ + l -= 1 + +static inline uint16_t _need16(const void* ptr) +{ + uint16_t v; + memcpy(&v, ptr, sizeof(v)); + return be16toh(v); +} + +#define need16(v, p, l) \ + if (l < 2) { \ + break; \ + } \ + v = _need16(p); \ + p += 2; \ + l -= 2 + +static inline uint32_t _need32(const void* ptr) +{ + uint32_t v; + memcpy(&v, ptr, sizeof(v)); + return be32toh(v); +} + +#define need32(v, p, l) \ + if (l < 4) { \ + break; \ + } \ + v = _need32(p); \ + p += 4; \ + l -= 4 + +#define needxb(b, x, p, l) \ + if (l < x) { \ + break; \ + } \ + memcpy(b, p, x); \ + p += x; \ + l -= x + +#define advancexb(x, p, l) \ + if (l < x) { \ + break; \ + } \ + p += x; \ + l -= x + +int core_object_dns_parse_header(core_object_dns_t* self) +{ + const core_object_payload_t* payload; + uint8_t byte; + mlassert_self(); + + if (!(payload = (core_object_payload_t*)self->obj_prev) || payload->obj_type != CORE_OBJECT_PAYLOAD) { + mlfatal("no obj_prev or invalid type"); + } + if (!payload->payload || !payload->len) { + mlfatal("no payload set or zero length"); + } + + self->payload = self->at = payload->payload; + self->len = self->left = payload->len; + + for (;;) { + if (self->includes_dnslen) { + need16(self->dnslen, self->at, self->left); + self->have_dnslen = 1; + } + need16(self->id, self->at, self->left); + self->have_id = 1; + + need8(byte, self->at, self->left); + self->qr = byte & (1 << 7) ? 1 : 0; + self->opcode = (byte >> 3) & 0xf; + self->aa = byte & (1 << 2) ? 1 : 0; + self->tc = byte & (1 << 1) ? 1 : 0; + self->rd = byte & (1 << 0) ? 1 : 0; + self->have_qr = self->have_opcode = self->have_aa = self->have_tc = self->have_rd = 1; + + need8(byte, self->at, self->left); + self->ra = byte & (1 << 7) ? 1 : 0; + self->z = byte & (1 << 6) ? 1 : 0; + self->ad = byte & (1 << 5) ? 1 : 0; + self->cd = byte & (1 << 4) ? 1 : 0; + self->rcode = byte & 0xf; + self->have_ra = self->have_z = self->have_ad = self->have_cd = self->have_rcode = 1; + + need16(self->qdcount, self->at, self->left); + self->have_qdcount = 1; + + need16(self->ancount, self->at, self->left); + self->have_ancount = 1; + + need16(self->nscount, self->at, self->left); + self->have_nscount = 1; + + need16(self->arcount, self->at, self->left); + self->have_arcount = 1; + + return 0; + } + + // TODO: error here on malformed/truncated? could be quite spammy + return _ERR_MALFORMED; +} + +static inline size_t _rdata_labels(uint16_t type) +{ + switch (type) { + case CORE_OBJECT_DNS_TYPE_NS: + case CORE_OBJECT_DNS_TYPE_MD: + case CORE_OBJECT_DNS_TYPE_MF: + case CORE_OBJECT_DNS_TYPE_CNAME: + case CORE_OBJECT_DNS_TYPE_MB: + case CORE_OBJECT_DNS_TYPE_MG: + case CORE_OBJECT_DNS_TYPE_MR: + case CORE_OBJECT_DNS_TYPE_PTR: + case CORE_OBJECT_DNS_TYPE_NXT: + case CORE_OBJECT_DNS_TYPE_DNAME: + case CORE_OBJECT_DNS_TYPE_NSEC: + case CORE_OBJECT_DNS_TYPE_TKEY: + case CORE_OBJECT_DNS_TYPE_TSIG: + return 1; + + case CORE_OBJECT_DNS_TYPE_SOA: + case CORE_OBJECT_DNS_TYPE_MINFO: + case CORE_OBJECT_DNS_TYPE_RP: + case CORE_OBJECT_DNS_TYPE_TALINK: + return 2; + + case CORE_OBJECT_DNS_TYPE_MX: + case CORE_OBJECT_DNS_TYPE_AFSDB: + case CORE_OBJECT_DNS_TYPE_RT: + case CORE_OBJECT_DNS_TYPE_KX: + case CORE_OBJECT_DNS_TYPE_LP: + return 1; + + case CORE_OBJECT_DNS_TYPE_PX: + return 2; + + case CORE_OBJECT_DNS_TYPE_SIG: + case CORE_OBJECT_DNS_TYPE_RRSIG: + return 1; + + case CORE_OBJECT_DNS_TYPE_SRV: + return 1; + + case CORE_OBJECT_DNS_TYPE_NAPTR: + return 1; + + case CORE_OBJECT_DNS_TYPE_HIP: + return 1; + + default: + break; + } + + return 0; +} + +static inline size_t _label(core_object_dns_t* self, core_object_dns_label_t* label, size_t labels) +{ + size_t n; + + for (n = 0; self->left && n < labels; n++) { + core_object_dns_label_t* l = &label[n]; + *l = _defaults_label; + + need8(l->length, self->at, self->left); + + if ((l->length & 0xc0) == 0xc0) { + need8(l->offset, self->at, self->left); + l->offset |= (l->length & 0x3f) << 8; + l->have_offset = 1; + return n; + } else if (l->length & 0xc0) { + l->extension_bits = l->length >> 6; + l->have_extension_bits = 1; + return n; + } else if (l->length) { + l->have_length = 1; + + l->offset = self->at - self->payload - 1; + advancexb(l->length, self->at, self->left); + l->have_dn = 1; + } else { + l->is_end = 1; + return n; + } + } + + return n; +} + +int core_object_dns_parse_q(core_object_dns_t* self, core_object_dns_q_t* q, core_object_dns_label_t* label, size_t labels) +{ + mlassert_self(); + mlassert(q, "q is nil"); + mlassert(label, "label is nil"); + mlassert(labels, "labels is zero"); + mlassert(self->at, "at is nil"); + + for (;;) { + *q = _defaults_q; + q->labels = _label(self, label, labels); + if (q->labels < labels) { + core_object_dns_label_t* l = &label[q->labels]; + if (!(l->have_offset | l->have_extension_bits | l->is_end)) { + // TODO: error here on malformed/truncated? could be quite spammy + return _ERR_MALFORMED; + } + } else { + mlwarning("need more labels, aborting DNS parsing"); + return _ERR_NEEDLABELS; + } + q->labels++; + + need16(q->type, self->at, self->left); + q->have_type = 1; + + need16(q->class, self->at, self->left); + q->have_class = 1; + + return 0; + } + + // TODO: error here on malformed/truncated? could be quite spammy + return _ERR_MALFORMED; +} + +int core_object_dns_parse_rr(core_object_dns_t* self, core_object_dns_rr_t* rr, core_object_dns_label_t* label, size_t labels) +{ + size_t rdata_label_sets; + mlassert_self(); + mlassert(rr, "rr is nil"); + mlassert(label, "label is nil"); + mlassert(labels, "labels is zero"); + mlassert(self->at, "at is nil"); + + for (;;) { + *rr = _defaults_rr; + rr->labels = _label(self, label, labels); + if (rr->labels < labels) { + core_object_dns_label_t* l = &label[rr->labels]; + if (!(l->have_offset | l->have_extension_bits | l->is_end)) { + // TODO: error here on malformed/truncated? could be quite spammy + return _ERR_MALFORMED; + } + } else { + mlwarning("need more labels, aborting DNS parsing"); + return _ERR_NEEDLABELS; + } + rr->labels++; + + need16(rr->type, self->at, self->left); + rr->have_type = 1; + + need16(rr->class, self->at, self->left); + rr->have_class = 1; + + need32(rr->ttl, self->at, self->left); + rr->have_ttl = 1; + + need16(rr->rdlength, self->at, self->left); + rr->have_rdlength = 1; + + rr->rdata_offset = self->at - self->payload; + if (!(rdata_label_sets = _rdata_labels(rr->type))) { + advancexb(rr->rdlength, self->at, self->left); + rr->have_rdata = 1; + return 0; + } + + switch (rr->type) { + case CORE_OBJECT_DNS_TYPE_MX: + case CORE_OBJECT_DNS_TYPE_AFSDB: + case CORE_OBJECT_DNS_TYPE_RT: + case CORE_OBJECT_DNS_TYPE_KX: + case CORE_OBJECT_DNS_TYPE_LP: + case CORE_OBJECT_DNS_TYPE_PX: + advancexb(2, self->at, self->left); + break; + + case CORE_OBJECT_DNS_TYPE_SIG: + case CORE_OBJECT_DNS_TYPE_RRSIG: + advancexb(18, self->at, self->left); + break; + + case CORE_OBJECT_DNS_TYPE_SRV: + advancexb(6, self->at, self->left); + break; + + case CORE_OBJECT_DNS_TYPE_NAPTR: { + uint8_t naptr_length; + + advancexb(4, self->at, self->left); + need8(naptr_length, self->at, self->left); + advancexb(naptr_length, self->at, self->left); + need8(naptr_length, self->at, self->left); + advancexb(naptr_length, self->at, self->left); + need8(naptr_length, self->at, self->left); + advancexb(naptr_length, self->at, self->left); + } break; + + case CORE_OBJECT_DNS_TYPE_HIP: { + uint8_t hit_length; + uint16_t pk_length; + + need8(hit_length, self->at, self->left); + advancexb(1, self->at, self->left); + need16(pk_length, self->at, self->left); + advancexb(hit_length, self->at, self->left); + advancexb(pk_length, self->at, self->left); + + if (self->at - self->payload >= rr->rdata_offset + rr->rdlength) { + rdata_label_sets = 0; + } + } break; + } + + while (rdata_label_sets) { + rr->rdata_labels += _label(self, &label[rr->labels + rr->rdata_labels], labels - rr->labels - rr->rdata_labels); + if (rr->labels + rr->rdata_labels < labels) { + core_object_dns_label_t* l = &label[rr->labels + rr->rdata_labels]; + if (!(l->have_offset | l->have_extension_bits | l->is_end)) { + // TODO: error here on malformed/truncated? could be quite spammy + return _ERR_MALFORMED; + } + } else { + mlwarning("need more labels, aborting DNS parsing"); + return _ERR_NEEDLABELS; + } + rr->rdata_labels++; + + if (rr->type == CORE_OBJECT_DNS_TYPE_HIP && self->at - self->payload < rr->rdata_offset + rr->rdlength) { + continue; + } + + rdata_label_sets--; + } + + if (self->at - self->payload < rr->rdata_offset + rr->rdlength) { + rr->padding_offset = self->at - self->payload; + rr->padding_length = rr->rdlength - (rr->padding_offset - rr->rdata_offset); + + advancexb(rr->padding_length, self->at, self->left); + + /* + * TODO: + * + * This can indicate padding but we do not set that we have padding + * yet because we need to fully understand all record types before + * that and process valid data after the labels + * + rr->have_padding = 1; + */ + } else if (self->at - self->payload > rr->rdata_offset + rr->rdlength) { + // TODO: error here on malformed/truncated? could be quite spammy + return _ERR_MALFORMED; + } + rr->have_rdata = 1; + + return 0; + } + + // TODO: error here on malformed/truncated? could be quite spammy + return _ERR_MALFORMED; +} diff --git a/src/core/object/dns.h b/src/core/object/dns.h new file mode 100644 index 0000000..5fbaf53 --- /dev/null +++ b/src/core/object/dns.h @@ -0,0 +1,184 @@ +/* + * Copyright (c) 2018-2021, OARC, Inc. + * All rights reserved. + * + * This file is part of dnsjit. + * + * dnsjit is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * dnsjit is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with dnsjit. If not, see <http://www.gnu.org/licenses/>. + */ + +#include "core/log.h" +#include "core/object.h" + +#ifndef __dnsjit_core_object_dns_h +#define __dnsjit_core_object_dns_h + +#include <netinet/in.h> +#include <sys/types.h> + +#include "core/object/dns.hh" + +#define CORE_OBJECT_DNS_INIT(prev) \ + { \ + CORE_OBJECT_INIT(CORE_OBJECT_DNS, prev) \ + , \ + 0, 0, 0, 0, 0, \ + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \ + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \ + } + +/* + * 2016-12-09 https://www.iana.org/assignments/dns-parameters/dns-parameters.xhtml + */ + +#define CORE_OBJECT_DNS_CLASS_IN 1 +#define CORE_OBJECT_DNS_CLASS_CH 3 +#define CORE_OBJECT_DNS_CLASS_HS 4 +#define CORE_OBJECT_DNS_CLASS_NONE 254 +#define CORE_OBJECT_DNS_CLASS_ANY 255 + +#define CORE_OBJECT_DNS_TYPE_A 1 +#define CORE_OBJECT_DNS_TYPE_NS 2 +#define CORE_OBJECT_DNS_TYPE_MD 3 +#define CORE_OBJECT_DNS_TYPE_MF 4 +#define CORE_OBJECT_DNS_TYPE_CNAME 5 +#define CORE_OBJECT_DNS_TYPE_SOA 6 +#define CORE_OBJECT_DNS_TYPE_MB 7 +#define CORE_OBJECT_DNS_TYPE_MG 8 +#define CORE_OBJECT_DNS_TYPE_MR 9 +#define CORE_OBJECT_DNS_TYPE_NULL 10 +#define CORE_OBJECT_DNS_TYPE_WKS 11 +#define CORE_OBJECT_DNS_TYPE_PTR 12 +#define CORE_OBJECT_DNS_TYPE_HINFO 13 +#define CORE_OBJECT_DNS_TYPE_MINFO 14 +#define CORE_OBJECT_DNS_TYPE_MX 15 +#define CORE_OBJECT_DNS_TYPE_TXT 16 +#define CORE_OBJECT_DNS_TYPE_RP 17 +#define CORE_OBJECT_DNS_TYPE_AFSDB 18 +#define CORE_OBJECT_DNS_TYPE_X25 19 +#define CORE_OBJECT_DNS_TYPE_ISDN 20 +#define CORE_OBJECT_DNS_TYPE_RT 21 +#define CORE_OBJECT_DNS_TYPE_NSAP 22 +#define CORE_OBJECT_DNS_TYPE_NSAP_PTR 23 +#define CORE_OBJECT_DNS_TYPE_SIG 24 +#define CORE_OBJECT_DNS_TYPE_KEY 25 +#define CORE_OBJECT_DNS_TYPE_PX 26 +#define CORE_OBJECT_DNS_TYPE_GPOS 27 +#define CORE_OBJECT_DNS_TYPE_AAAA 28 +#define CORE_OBJECT_DNS_TYPE_LOC 29 +#define CORE_OBJECT_DNS_TYPE_NXT 30 +#define CORE_OBJECT_DNS_TYPE_EID 31 +#define CORE_OBJECT_DNS_TYPE_NIMLOC 32 +#define CORE_OBJECT_DNS_TYPE_SRV 33 +#define CORE_OBJECT_DNS_TYPE_ATMA 34 +#define CORE_OBJECT_DNS_TYPE_NAPTR 35 +#define CORE_OBJECT_DNS_TYPE_KX 36 +#define CORE_OBJECT_DNS_TYPE_CERT 37 +#define CORE_OBJECT_DNS_TYPE_A6 38 +#define CORE_OBJECT_DNS_TYPE_DNAME 39 +#define CORE_OBJECT_DNS_TYPE_SINK 40 +#define CORE_OBJECT_DNS_TYPE_OPT 41 +#define CORE_OBJECT_DNS_TYPE_APL 42 +#define CORE_OBJECT_DNS_TYPE_DS 43 +#define CORE_OBJECT_DNS_TYPE_SSHFP 44 +#define CORE_OBJECT_DNS_TYPE_IPSECKEY 45 +#define CORE_OBJECT_DNS_TYPE_RRSIG 46 +#define CORE_OBJECT_DNS_TYPE_NSEC 47 +#define CORE_OBJECT_DNS_TYPE_DNSKEY 48 +#define CORE_OBJECT_DNS_TYPE_DHCID 49 +#define CORE_OBJECT_DNS_TYPE_NSEC3 50 +#define CORE_OBJECT_DNS_TYPE_NSEC3PARAM 51 +#define CORE_OBJECT_DNS_TYPE_TLSA 52 +#define CORE_OBJECT_DNS_TYPE_SMIMEA 53 +#define CORE_OBJECT_DNS_TYPE_HIP 55 +#define CORE_OBJECT_DNS_TYPE_NINFO 56 +#define CORE_OBJECT_DNS_TYPE_RKEY 57 +#define CORE_OBJECT_DNS_TYPE_TALINK 58 +#define CORE_OBJECT_DNS_TYPE_CDS 59 +#define CORE_OBJECT_DNS_TYPE_CDNSKEY 60 +#define CORE_OBJECT_DNS_TYPE_OPENPGPKEY 61 +#define CORE_OBJECT_DNS_TYPE_CSYNC 62 +#define CORE_OBJECT_DNS_TYPE_SPF 99 +#define CORE_OBJECT_DNS_TYPE_UINFO 100 +#define CORE_OBJECT_DNS_TYPE_UID 101 +#define CORE_OBJECT_DNS_TYPE_GID 102 +#define CORE_OBJECT_DNS_TYPE_UNSPEC 103 +#define CORE_OBJECT_DNS_TYPE_NID 104 +#define CORE_OBJECT_DNS_TYPE_L32 105 +#define CORE_OBJECT_DNS_TYPE_L64 106 +#define CORE_OBJECT_DNS_TYPE_LP 107 +#define CORE_OBJECT_DNS_TYPE_EUI48 108 +#define CORE_OBJECT_DNS_TYPE_EUI64 109 +#define CORE_OBJECT_DNS_TYPE_TKEY 249 +#define CORE_OBJECT_DNS_TYPE_TSIG 250 +#define CORE_OBJECT_DNS_TYPE_IXFR 251 +#define CORE_OBJECT_DNS_TYPE_AXFR 252 +#define CORE_OBJECT_DNS_TYPE_MAILB 253 +#define CORE_OBJECT_DNS_TYPE_MAILA 254 +#define CORE_OBJECT_DNS_TYPE_ANY 255 +#define CORE_OBJECT_DNS_TYPE_URI 256 +#define CORE_OBJECT_DNS_TYPE_CAA 257 +#define CORE_OBJECT_DNS_TYPE_AVC 258 +#define CORE_OBJECT_DNS_TYPE_TA 32768 +#define CORE_OBJECT_DNS_TYPE_DLV 32769 + +#define CORE_OBJECT_DNS_OPCODE_QUERY 0 +#define CORE_OBJECT_DNS_OPCODE_IQUERY 1 +#define CORE_OBJECT_DNS_OPCODE_STATUS 2 +#define CORE_OBJECT_DNS_OPCODE_NOTIFY 4 +#define CORE_OBJECT_DNS_OPCODE_UPDATE 5 + +#define CORE_OBJECT_DNS_RCODE_NOERROR 0 +#define CORE_OBJECT_DNS_RCODE_FORMERR 1 +#define CORE_OBJECT_DNS_RCODE_SERVFAIL 2 +#define CORE_OBJECT_DNS_RCODE_NXDOMAIN 3 +#define CORE_OBJECT_DNS_RCODE_NOTIMP 4 +#define CORE_OBJECT_DNS_RCODE_REFUSED 5 +#define CORE_OBJECT_DNS_RCODE_YXDOMAIN 6 +#define CORE_OBJECT_DNS_RCODE_YXRRSET 7 +#define CORE_OBJECT_DNS_RCODE_NXRRSET 8 +#define CORE_OBJECT_DNS_RCODE_NOTAUTH 9 +#define CORE_OBJECT_DNS_RCODE_NOTZONE 10 +#define CORE_OBJECT_DNS_RCODE_BADVERS 16 +#define CORE_OBJECT_DNS_RCODE_BADSIG 16 +#define CORE_OBJECT_DNS_RCODE_BADKEY 17 +#define CORE_OBJECT_DNS_RCODE_BADTIME 18 +#define CORE_OBJECT_DNS_RCODE_BADMODE 19 +#define CORE_OBJECT_DNS_RCODE_BADNAME 20 +#define CORE_OBJECT_DNS_RCODE_BADALG 21 +#define CORE_OBJECT_DNS_RCODE_BADTRUNC 22 +#define CORE_OBJECT_DNS_RCODE_BADCOOKIE 23 + +#define CORE_OBJECT_DNS_AFSDB_SUBTYPE_AFS3LOCSRV 1 +#define CORE_OBJECT_DNS_AFSDB_SUBTYPE_DCENCA_ROOT 2 + +#define CORE_OBJECT_DNS_DHCID_TYPE_1OCTET 0 +#define CORE_OBJECT_DNS_DHCID_TYPE_DATAOCTET 1 +#define CORE_OBJECT_DNS_DHCID_TYPE_CLIENT_DUID 2 + +#define CORE_OBJECT_DNS_EDNS0_OPT_LLQ 1 +#define CORE_OBJECT_DNS_EDNS0_OPT_UL 2 +#define CORE_OBJECT_DNS_EDNS0_OPT_NSID 3 +#define CORE_OBJECT_DNS_EDNS0_OPT_DAU 5 +#define CORE_OBJECT_DNS_EDNS0_OPT_DHU 6 +#define CORE_OBJECT_DNS_EDNS0_OPT_N3U 7 +#define CORE_OBJECT_DNS_EDNS0_OPT_CLIENT_SUBNET 8 +#define CORE_OBJECT_DNS_EDNS0_OPT_EXPIRE 9 +#define CORE_OBJECT_DNS_EDNS0_OPT_COOKIE 10 +#define CORE_OBJECT_DNS_EDNS0_OPT_TCP_KEEPALIVE 11 +#define CORE_OBJECT_DNS_EDNS0_OPT_PADDING 12 +#define CORE_OBJECT_DNS_EDNS0_OPT_CHAIN 13 +#define CORE_OBJECT_DNS_EDNS0_OPT_DEVICEID 26946 + +#endif diff --git a/src/core/object/dns.hh b/src/core/object/dns.hh new file mode 100644 index 0000000..dfe9719 --- /dev/null +++ b/src/core/object/dns.hh @@ -0,0 +1,119 @@ +/* + * Copyright (c) 2018-2021, OARC, Inc. + * All rights reserved. + * + * This file is part of dnsjit. + * + * dnsjit is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * dnsjit is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with dnsjit. If not, see <http://www.gnu.org/licenses/>. + */ + +//lua:require("dnsjit.core.log") +//lua:require("dnsjit.core.object_h") + +typedef struct core_object_dns_label { + uint8_t is_end; + uint8_t have_length; + uint8_t have_offset; + uint8_t have_extension_bits; + uint8_t have_dn; + uint8_t extension_bits; + + uint8_t length; + uint16_t offset; +} core_object_dns_label_t; + +typedef struct core_object_dns_rr { + uint8_t have_type; + uint8_t have_class; + uint8_t have_ttl; + uint8_t have_rdlength; + uint8_t have_rdata; + uint8_t have_rdata_labels; + uint8_t have_padding; + + uint16_t type; + uint16_t class; + uint32_t ttl; + uint16_t rdlength; + + size_t labels; + size_t rdata_offset; + size_t rdata_labels; + size_t padding_offset; + size_t padding_length; +} core_object_dns_rr_t; + +typedef struct core_object_dns_q { + uint8_t have_type; + uint8_t have_class; + + uint16_t type; + uint16_t class; + + size_t labels; +} core_object_dns_q_t; + +typedef struct core_object_dns { + const core_object_t* obj_prev; + int32_t obj_type; + + int includes_dnslen; + const uint8_t *payload, *at; + size_t len, left; + + uint8_t have_dnslen; + uint8_t have_id; + uint8_t have_qr; + uint8_t have_opcode; + uint8_t have_aa; + uint8_t have_tc; + uint8_t have_rd; + uint8_t have_ra; + uint8_t have_z; + uint8_t have_ad; + uint8_t have_cd; + uint8_t have_rcode; + uint8_t have_qdcount; + uint8_t have_ancount; + uint8_t have_nscount; + uint8_t have_arcount; + + uint16_t dnslen; + uint16_t id; + int8_t qr; + uint8_t opcode; + uint8_t aa; + uint8_t tc; + uint8_t rd; + uint8_t ra; + uint8_t z; + uint8_t ad; + uint8_t cd; + uint8_t rcode; + uint16_t qdcount; + uint16_t ancount; + uint16_t nscount; + uint16_t arcount; +} core_object_dns_t; + +core_log_t* core_object_dns_log(); + +core_object_dns_t* core_object_dns_new(); +core_object_dns_t* core_object_dns_copy(const core_object_dns_t* self); +void core_object_dns_free(core_object_dns_t* self); +void core_object_dns_reset(core_object_dns_t* self, const core_object_t* obj); + +int core_object_dns_parse_header(core_object_dns_t* self); +int core_object_dns_parse_q(core_object_dns_t* self, core_object_dns_q_t* q, core_object_dns_label_t* label, size_t labels); +int core_object_dns_parse_rr(core_object_dns_t* self, core_object_dns_rr_t* rr, core_object_dns_label_t* label, size_t labels); diff --git a/src/core/object/dns.lua b/src/core/object/dns.lua new file mode 100644 index 0000000..e8fb12b --- /dev/null +++ b/src/core/object/dns.lua @@ -0,0 +1,797 @@ +-- Copyright (c) 2018-2021, OARC, Inc. +-- All rights reserved. +-- +-- This file is part of dnsjit. +-- +-- dnsjit is free software: you can redistribute it and/or modify +-- it under the terms of the GNU General Public License as published by +-- the Free Software Foundation, either version 3 of the License, or +-- (at your option) any later version. +-- +-- dnsjit is distributed in the hope that it will be useful, +-- but WITHOUT ANY WARRANTY; without even the implied warranty of +-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +-- GNU General Public License for more details. +-- +-- You should have received a copy of the GNU General Public License +-- along with dnsjit. If not, see <http://www.gnu.org/licenses/>. + +-- dnsjit.core.object.dns +-- Container of a DNS message +-- .SS Parse DNS header and check if query or response +-- local dns = require("dnsjit.core.object.dns").new(payload) +-- if dns:parse_header() == 0 then +-- if dns.qr == 0 then +-- print(dns.id, dns.opcode_tostring(dns.opcode)) +-- else +-- print(dns.id, dns.rcode_tostring(dns.rcode)) +-- end +-- end +-- .SS Print a DNS payload +-- local dns = require("dnsjit.core.object.dns").new(payload) +-- dns:print() +-- .SS Parse a DNS payload +-- local dns = require("dnsjit.core.object.dns").new(payload) +-- local qs, q_labels, rrs, rr_labels = dns:parse() +-- if qs and q_labels then +-- ... +-- if rrs and rr_labels then +-- ... +-- end +-- end +-- +-- The object that describes a DNS message. +-- .SS Attributes +-- .TP +-- includes_dnslen +-- If non-zero then this indicates that the DNS length is included in the +-- payload (for example if the transport is TCP) and will affect parsing of it. +-- .TP +-- have_dnslen +-- Set if the dnslen was included in the payload and could be read. +-- .TP +-- have_id +-- Set if there is a DNS ID. +-- .TP +-- have_qr +-- Set if there is a QR flag. +-- .TP +-- have_opcode +-- Set if there is an OPCODE. +-- .TP +-- have_aa +-- Set if there is a AA flag. +-- .TP +-- have_tc +-- Set if there is a TC flag. +-- .TP +-- have_rd +-- Set if there is a RD flag. +-- .TP +-- have_ra +-- Set if there is a RA flag. +-- .TP +-- have_z +-- Set if there is a Z flag. +-- .TP +-- have_ad +-- Set if there is a AD flag. +-- .TP +-- have_cd +-- Set if there is a CD flag. +-- .TP +-- have_rcode +-- Set if there is a RCODE. +-- .TP +-- have_qdcount +-- Set if there is an QDCOUNT. +-- .TP +-- have_ancount +-- Set if there is an ANCOUNT. +-- .TP +-- have_nscount +-- Set if there is a NSCOUNT. +-- .TP +-- have_arcount +-- Set if there is an ARCOUNT. +-- .TP +-- dnslen +-- The DNS length found in the payload. +-- .TP +-- id +-- The DNS ID. +-- .TP +-- qr +-- The QR flag. +-- .TP +-- opcode +-- The OPCODE. +-- .TP +-- aa +-- The AA flag. +-- .TP +-- tc +-- The TC flag. +-- .TP +-- rd +-- The RD flag. +-- .TP +-- ra +-- The RA flag. +-- .TP +-- z +-- The Z flag. +-- .TP +-- ad +-- The AD flag. +-- .TP +-- cd +-- The CD flag. +-- .TP +-- rcode +-- The RCODE. +-- .TP +-- qdcount +-- The QDCOUNT. +-- .TP +-- ancount +-- The ANCOUNT. +-- .TP +-- nscount +-- The NSCOUNT. +-- .TP +-- arcount +-- The ARCOUNT. +-- .SS Constants +-- The following tables exists for DNS parameters, taken from +-- .I https://www.iana.org/assignments/dns-parameters/dns-parameters.xhtml +-- on the 2016-12-09. +-- .LP +-- .IR CLASS , +-- .IR CLASS_STR , +-- .IR TYPE , +-- .IR TYPE_STR , +-- .IR OPCODE , +-- .IR OPCODE_STR , +-- .IR RCODE , +-- .IR RCODE_STR , +-- .IR AFSDB , +-- .IR AFSDB_STR , +-- .IR DHCID , +-- .IR DHCID_STR , +-- .IR ENDS0 , +-- .IR ENDS0_STR +-- .LP +-- The +-- .I *_STR +-- tables can be used to get a textual representation of the numbers, see also +-- .IR class_tostring() , +-- .IR type_tostring() , +-- .IR opcode_tostring() , +-- .IR rcode_tostring() , +-- .IR afsdb_tostring() , +-- .I dhcid_tostring() +-- and +-- .IR edns0_tostring() . +module(...,package.seeall) + +require("dnsjit.core.object.dns_h") +local label = require("dnsjit.core.object.dns.label") +local Q = require("dnsjit.core.object.dns.q") +local RR = require("dnsjit.core.object.dns.rr") +local ffi = require("ffi") +local C = ffi.C + +local t_name = "core_object_dns_t" +local core_object_dns_t +local Dns = { + CLASS = { + IN = 1, + CH = 3, + HS = 4, + NONE = 254, + ANY = 255, + }, + TYPE = { + A = 1, + NS = 2, + MD = 3, + MF = 4, + CNAME = 5, + SOA = 6, + MB = 7, + MG = 8, + MR = 9, + NULL = 10, + WKS = 11, + PTR = 12, + HINFO = 13, + MINFO = 14, + MX = 15, + TXT = 16, + RP = 17, + AFSDB = 18, + X25 = 19, + ISDN = 20, + RT = 21, + NSAP = 22, + NSAP_PTR = 23, + SIG = 24, + KEY = 25, + PX = 26, + GPOS = 27, + AAAA = 28, + LOC = 29, + NXT = 30, + EID = 31, + NIMLOC = 32, + SRV = 33, + ATMA = 34, + NAPTR = 35, + KX = 36, + CERT = 37, + A6 = 38, + DNAME = 39, + SINK = 40, + OPT = 41, + APL = 42, + DS = 43, + SSHFP = 44, + IPSECKEY = 45, + RRSIG = 46, + NSEC = 47, + DNSKEY = 48, + DHCID = 49, + NSEC3 = 50, + NSEC3PARAM = 51, + TLSA = 52, + SMIMEA = 53, + HIP = 55, + NINFO = 56, + RKEY = 57, + TALINK = 58, + CDS = 59, + CDNSKEY = 60, + OPENPGPKEY = 61, + CSYNC = 62, + SPF = 99, + UINFO = 100, + UID = 101, + GID = 102, + UNSPEC = 103, + NID = 104, + L32 = 105, + L64 = 106, + LP = 107, + EUI48 = 108, + EUI64 = 109, + TKEY = 249, + TSIG = 250, + IXFR = 251, + AXFR = 252, + MAILB = 253, + MAILA = 254, + ANY = 255, + URI = 256, + CAA = 257, + AVC = 258, + TA = 32768, + DLV = 32769, + }, + OPCODE = { + QUERY = 0, + IQUERY = 1, + STATUS = 2, + NOTIFY = 4, + UPDATE = 5, + }, + RCODE = { + NOERROR = 0, + FORMERR = 1, + SERVFAIL = 2, + NXDOMAIN = 3, + NOTIMP = 4, + REFUSED = 5, + YXDOMAIN = 6, + YXRRSET = 7, + NXRRSET = 8, + NOTAUTH = 9, + NOTZONE = 10, + BADVERS = 16, + BADSIG = 16, + BADKEY = 17, + BADTIME = 18, + BADMODE = 19, + BADNAME = 20, + BADALG = 21, + BADTRUNC = 22, + BADCOOKIE = 23, + }, + AFSDB = { + SUBTYPE_AFS3LOCSRV = 1, + SUBTYPE_DCENCA_ROOT = 2, + }, + DHCID = { + TYPE_1OCTET = 0, + TYPE_DATAOCTET = 1, + TYPE_CLIENT_DUID = 2, + }, + EDNS0 = { + OPT_LLQ = 1, + OPT_UL = 2, + OPT_NSID = 3, + OPT_DAU = 5, + OPT_DHU = 6, + OPT_N3U = 7, + OPT_CLIENT_SUBNET = 8, + OPT_EXPIRE = 9, + OPT_COOKIE = 10, + OPT_TCP_KEEPALIVE = 11, + OPT_PADDING = 12, + OPT_CHAIN = 13, + OPT_DEVICEID = 26946, + }, +} +local _CLASS = {} +_CLASS[Dns.CLASS.IN] = "IN" +_CLASS[Dns.CLASS.CH] = "CH" +_CLASS[Dns.CLASS.HS] = "HS" +_CLASS[Dns.CLASS.NONE] = "NONE" +_CLASS[Dns.CLASS.ANY] = "ANY" +local _TYPE = {} +_TYPE[Dns.TYPE.A] = "A" +_TYPE[Dns.TYPE.NS] = "NS" +_TYPE[Dns.TYPE.MD] = "MD" +_TYPE[Dns.TYPE.MF] = "MF" +_TYPE[Dns.TYPE.CNAME] = "CNAME" +_TYPE[Dns.TYPE.SOA] = "SOA" +_TYPE[Dns.TYPE.MB] = "MB" +_TYPE[Dns.TYPE.MG] = "MG" +_TYPE[Dns.TYPE.MR] = "MR" +_TYPE[Dns.TYPE.NULL] = "NULL" +_TYPE[Dns.TYPE.WKS] = "WKS" +_TYPE[Dns.TYPE.PTR] = "PTR" +_TYPE[Dns.TYPE.HINFO] = "HINFO" +_TYPE[Dns.TYPE.MINFO] = "MINFO" +_TYPE[Dns.TYPE.MX] = "MX" +_TYPE[Dns.TYPE.TXT] = "TXT" +_TYPE[Dns.TYPE.RP] = "RP" +_TYPE[Dns.TYPE.AFSDB] = "AFSDB" +_TYPE[Dns.TYPE.X25] = "X25" +_TYPE[Dns.TYPE.ISDN] = "ISDN" +_TYPE[Dns.TYPE.RT] = "RT" +_TYPE[Dns.TYPE.NSAP] = "NSAP" +_TYPE[Dns.TYPE.NSAP_PTR] = "NSAP_PTR" +_TYPE[Dns.TYPE.SIG] = "SIG" +_TYPE[Dns.TYPE.KEY] = "KEY" +_TYPE[Dns.TYPE.PX] = "PX" +_TYPE[Dns.TYPE.GPOS] = "GPOS" +_TYPE[Dns.TYPE.AAAA] = "AAAA" +_TYPE[Dns.TYPE.LOC] = "LOC" +_TYPE[Dns.TYPE.NXT] = "NXT" +_TYPE[Dns.TYPE.EID] = "EID" +_TYPE[Dns.TYPE.NIMLOC] = "NIMLOC" +_TYPE[Dns.TYPE.SRV] = "SRV" +_TYPE[Dns.TYPE.ATMA] = "ATMA" +_TYPE[Dns.TYPE.NAPTR] = "NAPTR" +_TYPE[Dns.TYPE.KX] = "KX" +_TYPE[Dns.TYPE.CERT] = "CERT" +_TYPE[Dns.TYPE.A6] = "A6" +_TYPE[Dns.TYPE.DNAME] = "DNAME" +_TYPE[Dns.TYPE.SINK] = "SINK" +_TYPE[Dns.TYPE.OPT] = "OPT" +_TYPE[Dns.TYPE.APL] = "APL" +_TYPE[Dns.TYPE.DS] = "DS" +_TYPE[Dns.TYPE.SSHFP] = "SSHFP" +_TYPE[Dns.TYPE.IPSECKEY] = "IPSECKEY" +_TYPE[Dns.TYPE.RRSIG] = "RRSIG" +_TYPE[Dns.TYPE.NSEC] = "NSEC" +_TYPE[Dns.TYPE.DNSKEY] = "DNSKEY" +_TYPE[Dns.TYPE.DHCID] = "DHCID" +_TYPE[Dns.TYPE.NSEC3] = "NSEC3" +_TYPE[Dns.TYPE.NSEC3PARAM] = "NSEC3PARAM" +_TYPE[Dns.TYPE.TLSA] = "TLSA" +_TYPE[Dns.TYPE.SMIMEA] = "SMIMEA" +_TYPE[Dns.TYPE.HIP] = "HIP" +_TYPE[Dns.TYPE.NINFO] = "NINFO" +_TYPE[Dns.TYPE.RKEY] = "RKEY" +_TYPE[Dns.TYPE.TALINK] = "TALINK" +_TYPE[Dns.TYPE.CDS] = "CDS" +_TYPE[Dns.TYPE.CDNSKEY] = "CDNSKEY" +_TYPE[Dns.TYPE.OPENPGPKEY] = "OPENPGPKEY" +_TYPE[Dns.TYPE.CSYNC] = "CSYNC" +_TYPE[Dns.TYPE.SPF] = "SPF" +_TYPE[Dns.TYPE.UINFO] = "UINFO" +_TYPE[Dns.TYPE.UID] = "UID" +_TYPE[Dns.TYPE.GID] = "GID" +_TYPE[Dns.TYPE.UNSPEC] = "UNSPEC" +_TYPE[Dns.TYPE.NID] = "NID" +_TYPE[Dns.TYPE.L32] = "L32" +_TYPE[Dns.TYPE.L64] = "L64" +_TYPE[Dns.TYPE.LP] = "LP" +_TYPE[Dns.TYPE.EUI48] = "EUI48" +_TYPE[Dns.TYPE.EUI64] = "EUI64" +_TYPE[Dns.TYPE.TKEY] = "TKEY" +_TYPE[Dns.TYPE.TSIG] = "TSIG" +_TYPE[Dns.TYPE.IXFR] = "IXFR" +_TYPE[Dns.TYPE.AXFR] = "AXFR" +_TYPE[Dns.TYPE.MAILB] = "MAILB" +_TYPE[Dns.TYPE.MAILA] = "MAILA" +_TYPE[Dns.TYPE.ANY] = "ANY" +_TYPE[Dns.TYPE.URI] = "URI" +_TYPE[Dns.TYPE.CAA] = "CAA" +_TYPE[Dns.TYPE.AVC] = "AVC" +_TYPE[Dns.TYPE.TA] = "TA" +_TYPE[Dns.TYPE.DLV] = "DLV" +local _OPCODE = {} +_OPCODE[Dns.OPCODE.QUERY] = "QUERY" +_OPCODE[Dns.OPCODE.IQUERY] = "IQUERY" +_OPCODE[Dns.OPCODE.STATUS] = "STATUS" +_OPCODE[Dns.OPCODE.NOTIFY] = "NOTIFY" +_OPCODE[Dns.OPCODE.UPDATE] = "UPDATE" +local _RCODE = {} +_RCODE[Dns.RCODE.NOERROR] = "NOERROR" +_RCODE[Dns.RCODE.FORMERR] = "FORMERR" +_RCODE[Dns.RCODE.SERVFAIL] = "SERVFAIL" +_RCODE[Dns.RCODE.NXDOMAIN] = "NXDOMAIN" +_RCODE[Dns.RCODE.NOTIMP] = "NOTIMP" +_RCODE[Dns.RCODE.REFUSED] = "REFUSED" +_RCODE[Dns.RCODE.YXDOMAIN] = "YXDOMAIN" +_RCODE[Dns.RCODE.YXRRSET] = "YXRRSET" +_RCODE[Dns.RCODE.NXRRSET] = "NXRRSET" +_RCODE[Dns.RCODE.NOTAUTH] = "NOTAUTH" +_RCODE[Dns.RCODE.NOTZONE] = "NOTZONE" +_RCODE[Dns.RCODE.BADVERS] = "BADVERS" +_RCODE[Dns.RCODE.BADSIG] = "BADSIG" +_RCODE[Dns.RCODE.BADKEY] = "BADKEY" +_RCODE[Dns.RCODE.BADTIME] = "BADTIME" +_RCODE[Dns.RCODE.BADMODE] = "BADMODE" +_RCODE[Dns.RCODE.BADNAME] = "BADNAME" +_RCODE[Dns.RCODE.BADALG] = "BADALG" +_RCODE[Dns.RCODE.BADTRUNC] = "BADTRUNC" +_RCODE[Dns.RCODE.BADCOOKIE] = "BADCOOKIE" +local _AFSDB = {} +_AFSDB[Dns.AFSDB.SUBTYPE_AFS3LOCSRV] = "SUBTYPE_AFS3LOCSRV" +_AFSDB[Dns.AFSDB.SUBTYPE_DCENCA_ROOT] = "SUBTYPE_DCENCA_ROOT" +local _DHCID = {} +_DHCID[Dns.DHCID.TYPE_1OCTET] = "TYPE_1OCTET" +_DHCID[Dns.DHCID.TYPE_DATAOCTET] = "TYPE_DATAOCTET" +_DHCID[Dns.DHCID.TYPE_CLIENT_DUID] = "TYPE_CLIENT_DUID" +local _EDNS0 = {} +_EDNS0[Dns.EDNS0.OPT_LLQ] = "OPT_LLQ" +_EDNS0[Dns.EDNS0.OPT_UL] = "OPT_UL" +_EDNS0[Dns.EDNS0.OPT_NSID] = "OPT_NSID" +_EDNS0[Dns.EDNS0.OPT_DAU] = "OPT_DAU" +_EDNS0[Dns.EDNS0.OPT_DHU] = "OPT_DHU" +_EDNS0[Dns.EDNS0.OPT_N3U] = "OPT_N3U" +_EDNS0[Dns.EDNS0.OPT_CLIENT_SUBNET] = "OPT_CLIENT_SUBNET" +_EDNS0[Dns.EDNS0.OPT_EXPIRE] = "OPT_EXPIRE" +_EDNS0[Dns.EDNS0.OPT_COOKIE] = "OPT_COOKIE" +_EDNS0[Dns.EDNS0.OPT_TCP_KEEPALIVE] = "OPT_TCP_KEEPALIVE" +_EDNS0[Dns.EDNS0.OPT_PADDING] = "OPT_PADDING" +_EDNS0[Dns.EDNS0.OPT_CHAIN] = "OPT_CHAIN" +_EDNS0[Dns.EDNS0.OPT_DEVICEID] = "OPT_DEVICEID" +Dns.CLASS_STR = _CLASS +Dns.TYPE_STR = _TYPE +Dns.OPCODE_STR = _OPCODE +Dns.RCODE_STR = _RCODE +Dns.AFSDB_STR = _AFSDB +Dns.DHCID_STR = _DHCID +Dns.EDNS0_STR = _EDNS0 + +-- Create a new DNS object, optionally on-top of another object. +function Dns.new(obj) + local self = C.core_object_dns_new() + self.obj_prev = obj + ffi.gc(self, C.core_object_dns_free) + return self +end + +-- Return the textual type of the object. +function Dns:type() + return "dns" +end + +-- Return the previous object. +function Dns:prev() + return self.obj_prev +end + +-- Cast the object to the underlining object module and return it. +function Dns:cast() + return self +end + +-- Cast the object to the generic object module and return it. +function Dns:uncast() + return ffi.cast("core_object_t*", self) +end + +-- Make a copy of the object and return it. +function Dns:copy() + return C.core_object_dns_copy(self) +end + +-- Free the object, should only be used on copies or otherwise allocated. +function Dns:free() + C.core_object_dns_free(self) +end + +-- Return the Log object to control logging of this module. +function Dns:log() + return C.core_object_dns_log() +end + +-- Begin parsing the underlaying object, first the header is parsed then +-- optionally continue calling +-- .IR parse_q () +-- for the number of questions (see +-- .IR qdcount ). +-- After that continue calling +-- .IR parse_rr () +-- for the number of answers, authorities and additionals resource records +-- (see +-- .IR ancount ", " +-- .I nscount +-- and +-- .IR arcount ). +-- Returns 0 on success or negative integer on error which can be for +-- malformed or truncated DNS (-2) or if more space for labels is needed (-3). +function Dns:parse_header() + return C.core_object_dns_parse_header(self) +end + +-- Parse the next resource record as a question. +-- Returns 0 on success or negative integer on error which can be for +-- malformed or truncated DNS (-2) or if more space for labels is needed (-3). +function Dns:parse_q(q, labels, num_labels) + return C.core_object_dns_parse_q(self, q, labels, num_labels) +end + +-- Parse the next resource record. +-- Returns 0 on success or negative integer on error which can be for +-- malformed or truncated DNS (-2) or if more space for labels is needed (-3). +function Dns:parse_rr(rr, labels, num_labels) + return C.core_object_dns_parse_rr(self, rr, labels, num_labels) +end + +-- Begin parsing the underlaying object using +-- .IR parse_header "(), " +-- .IR parse_q () +-- and +-- .IR parse_rr (). +-- The optional +-- .I num_labels +-- can be used to set a specific number of labels used for each question +-- and resource record (default 16). +-- Returns result code, an array of questions, an array of question labels, +-- an array of resource records and an array of resource records labels. +-- Result code is 0 on success or negative integer on error which can be for +-- malformed or truncated DNS (-2) or if more space for labels is needed (-3). +function Dns:parse(num_labels) + local qs, qls, rrs, rrls = {}, {}, {}, {} + if num_labels == nil then + num_labels = 16 + end + + ret = self:parse_header() + if ret ~= 0 then + return ret, qs, qls, rrs, rrls + end + for n = 1, self.qdcount do + local labels = label.new(num_labels) + local q = Q.new() + local ret = C.core_object_dns_parse_q(self, q, labels, num_labels) + + if ret ~= 0 then + return ret, qs, qls, rrs, rrls + end + table.insert(qs, q) + table.insert(qls, labels) + end + for n = 1, self.ancount do + local labels = label.new(num_labels) + local rr = RR.new() + local ret = C.core_object_dns_parse_rr(self, rr, labels, num_labels) + + if ret ~= 0 then + return ret, qs, qls, rrs, rrls + end + table.insert(rrs, rr) + table.insert(rrls, labels) + end + for n = 1, self.nscount do + local labels = label.new(num_labels) + local rr = RR.new() + local ret = C.core_object_dns_parse_rr(self, rr, labels, num_labels) + + if ret ~= 0 then + return ret, qs, qls, rrs, rrls + end + table.insert(rrs, rr) + table.insert(rrls, labels) + end + for n = 1, self.arcount do + local labels = label.new(num_labels) + local rr = RR.new() + local ret = C.core_object_dns_parse_rr(self, rr, labels, num_labels) + + if ret ~= 0 then + return ret, qs, qls, rrs, rrls + end + table.insert(rrs, rr) + table.insert(rrls, labels) + end + + return 0, qs, qls, rrs, rrls +end + +-- Begin parsing the underlaying object using +-- .IR parse_header "(), " +-- .IR parse_q () +-- and +-- .IR parse_rr (), +-- and print it's content. +-- The optional +-- .I num_labels +-- can be used to set a specific number of labels used for each question +-- and resource record (default 16). +function Dns:print(num_labels) + if num_labels == nil then + num_labels = 16 + end + local labels = label.new(num_labels) + local q = Q.new() + local rr = RR.new() + + if self:parse_header() ~= 0 then + return + end + + local flags = {} + if self.have_aa and self.aa == 1 then + table.insert(flags, "AA") + end + if self.have_tc and self.tc == 1 then + table.insert(flags, "TC") + end + if self.have_rd and self.rd == 1 then + table.insert(flags, "RD") + end + if self.have_ra and self.ra == 1 then + table.insert(flags, "RA") + end + if self.have_z and self.z == 1 then + table.insert(flags, "Z") + end + if self.have_ad and self.ad == 1 then + table.insert(flags, "AD") + end + if self.have_cd and self.cd == 1 then + table.insert(flags, "CD") + end + + print("id:", self.id) + print("", "qr:", self.qr) + print("", "opcode:", Dns.opcode_tostring(self.opcode)) + print("", "flags:", table.concat(flags, " ")) + print("", "rcode:", Dns.rcode_tostring(self.rcode)) + print("", "qdcount:", self.qdcount) + print("", "ancount:", self.ancount) + print("", "nscount:", self.nscount) + print("", "arcount:", self.arcount) + + if self.qdcount > 0 then + print("questions:", "class", "type", "labels") + for n = 1, self.qdcount do + if C.core_object_dns_parse_q(self, q, labels, num_labels) ~= 0 then + return + end + print("", Dns.class_tostring(q.class), Dns.type_tostring(q.type), label.tooffstr(self, labels, num_labels)) + end + end + if self.ancount > 0 then + print("answers:", "class", "type", "ttl", "labels", "RR labels") + for n = 1, self.ancount do + if C.core_object_dns_parse_rr(self, rr, labels, num_labels) ~= 0 then + return + end + if rr.rdata_labels == 0 then + print("", Dns.class_tostring(rr.class), Dns.type_tostring(rr.type), rr.ttl, label.tooffstr(self, labels, rr.labels)) + else + print("", Dns.class_tostring(rr.class), Dns.type_tostring(rr.type), rr.ttl, label.tooffstr(self, labels, rr.labels), label.tooffstr(self, labels, rr.rdata_labels, rr.labels)) + end + end + end + if self.nscount > 0 then + print("authorities:", "class", "type", "ttl", "labels", "RR labels") + for n = 1, self.nscount do + if C.core_object_dns_parse_rr(self, rr, labels, num_labels) ~= 0 then + return + end + if rr.rdata_labels == 0 then + print("", Dns.class_tostring(rr.class), Dns.type_tostring(rr.type), rr.ttl, label.tooffstr(self, labels, rr.labels)) + else + print("", Dns.class_tostring(rr.class), Dns.type_tostring(rr.type), rr.ttl, label.tooffstr(self, labels, rr.labels), label.tooffstr(self, labels, rr.rdata_labels, rr.labels)) + end + end + end + if self.arcount > 0 then + print("additionals:", "class", "type", "ttl", "labels", "RR labels") + for n = 1, self.arcount do + if C.core_object_dns_parse_rr(self, rr, labels, num_labels) ~= 0 then + return + end + if rr.rdata_labels == 0 then + print("", Dns.class_tostring(rr.class), Dns.type_tostring(rr.type), rr.ttl, label.tooffstr(self, labels, rr.labels)) + else + print("", Dns.class_tostring(rr.class), Dns.type_tostring(rr.type), rr.ttl, label.tooffstr(self, labels, rr.labels), label.tooffstr(self, labels, rr.rdata_labels, rr.labels)) + end + end + end +end + +-- Return the textual name for a class. +function Dns.class_tostring(class) + if Dns.CLASS_STR[class] == nil then + return "UNKNOWN("..class..")" + end + return Dns.CLASS_STR[class] +end + +-- Return the textual name for a type. +function Dns.type_tostring(type) + if Dns.TYPE_STR[type] == nil then + return "UNKNOWN("..type..")" + end + return Dns.TYPE_STR[type] +end + +-- Return the textual name for an opcode. +function Dns.opcode_tostring(opcode) + if Dns.OPCODE_STR[opcode] == nil then + return "UNKNOWN("..opcode..")" + end + return Dns.OPCODE_STR[opcode] +end + +-- Return the textual name for a rcode. +function Dns.rcode_tostring(rcode) + if Dns.RCODE_STR[rcode] == nil then + return "UNKNOWN("..rcode..")" + end + return Dns.RCODE_STR[rcode] +end + +-- Return the textual name for an afsdb subtype. +function Dns.afsdb_tostring(afsdb) + if Dns.AFSDB_STR[afsdb] == nil then + return "UNKNOWN("..afsdb..")" + end + return Dns.AFSDB_STR[afsdb] +end + +-- Return the textual name for a dhcid type. +function Dns.dhcid_tostring(dhcid) + if Dns.DHCID_STR[dhcid] == nil then + return "UNKNOWN("..dhcid..")" + end + return Dns.DHCID_STR[dhcid] +end + +-- Return the textual name for an EDNS0 OPT record. +function Dns.edns0_tostring(edns0) + if Dns.EDNS0_STR[edns0] == nil then + return "UNKNOWN("..edns0..")" + end + return Dns.EDNS0_STR[edns0] +end + +core_object_dns_t = ffi.metatype(t_name, { __index = Dns }) + +-- dnsjit.core.object (3), +-- dnsjit.core.object.payload (3), +-- dnsjit.core.object.dns.label (3), +-- dnsjit.core.object.dns.q (3), +-- dnsjit.core.object.dns.rr (3) +return Dns diff --git a/src/core/object/dns/label.lua b/src/core/object/dns/label.lua new file mode 100644 index 0000000..bc78758 --- /dev/null +++ b/src/core/object/dns/label.lua @@ -0,0 +1,118 @@ +-- Copyright (c) 2018-2021, OARC, Inc. +-- All rights reserved. +-- +-- This file is part of dnsjit. +-- +-- dnsjit is free software: you can redistribute it and/or modify +-- it under the terms of the GNU General Public License as published by +-- the Free Software Foundation, either version 3 of the License, or +-- (at your option) any later version. +-- +-- dnsjit is distributed in the hope that it will be useful, +-- but WITHOUT ANY WARRANTY; without even the implied warranty of +-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +-- GNU General Public License for more details. +-- +-- You should have received a copy of the GNU General Public License +-- along with dnsjit. If not, see <http://www.gnu.org/licenses/>. + +-- dnsjit.core.object.dns.label +-- Container of a DNS label +-- +-- The object that describes a DNS label. +-- To extract a domain name label first check that +-- .I have_dn +-- is set, then use +-- .I "offset + 1" +-- to indicate where in the payload the label start and +-- .I length +-- for how many bytes long it is. +-- .SS Attributes +-- .TP +-- is_end +-- .TP +-- have_length +-- Set if there is a length. +-- .TP +-- have_offset +-- Set if there is an offset. +-- .TP +-- have_extension_bits +-- Set if there is extension bits. +-- .TP +-- have_dn +-- Set if the label contained a domain name. +-- .TP +-- extension_bits +-- The extension bits. +-- .TP +-- length +-- The length of the domain name. +-- .TP +-- offset +-- If +-- .I have_dn +-- is set then this contains the offset within the payload to where this label +-- start otherwise it contains the offset to another label. +module(...,package.seeall) + +require("dnsjit.core.object.dns_h") +local ffi = require("ffi") + +local Label = {} + +-- Create a new array of labels. +function Label.new(size) + return ffi.new("core_object_dns_label_t[?]", size) +end + +-- Returns labels as a string and an offset to the next label. +-- The string may be nil if the first label was an offset. +-- The offset may be nil if the last label was an extension bits or end marker. +function Label.tostring(dns, labels, num_labels, offset_labels) + if offset_labels == nil then + offset_labels = 0 + end + local dn + for n = 1, tonumber(num_labels) do + local label = labels[n - 1 + offset_labels] + + if label.have_dn == 1 then + if dn == nil then + dn = "" + end + dn = dn .. ffi.string(dns.payload + label.offset + 1, label.length) .. "." + elseif label.have_offset == 1 then + return dn, label.offset + else + return dn, nil + end + end + return dn, nil +end + +-- Returns labels as a string which also includes a textual notation of the +-- offset in the form of +-- .IR "<offset>label" . +function Label.tooffstr(dns, labels, num_labels, offset_labels) + if offset_labels == nil then + offset_labels = 0 + end + local dn = "" + for n = 1, tonumber(num_labels) do + local label = labels[n - 1 + offset_labels] + + if label.have_dn == 1 then + dn = dn .. "<" .. tonumber(label.offset) .. ">" .. ffi.string(dns.payload + label.offset + 1, label.length) .. "." + elseif label.have_offset == 1 then + dn = dn .. "<" .. tonumber(label.offset) .. ">" + break + else + break + end + end + return dn +end + +-- dnsjit.core.object.dns (3) +return Label diff --git a/src/core/object/dns/q.lua b/src/core/object/dns/q.lua new file mode 100644 index 0000000..f65d9e8 --- /dev/null +++ b/src/core/object/dns/q.lua @@ -0,0 +1,52 @@ +-- Copyright (c) 2018-2021, OARC, Inc. +-- All rights reserved. +-- +-- This file is part of dnsjit. +-- +-- dnsjit is free software: you can redistribute it and/or modify +-- it under the terms of the GNU General Public License as published by +-- the Free Software Foundation, either version 3 of the License, or +-- (at your option) any later version. +-- +-- dnsjit is distributed in the hope that it will be useful, +-- but WITHOUT ANY WARRANTY; without even the implied warranty of +-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +-- GNU General Public License for more details. +-- +-- You should have received a copy of the GNU General Public License +-- along with dnsjit. If not, see <http://www.gnu.org/licenses/>. + +-- dnsjit.core.object.dns.q +-- Container of a DNS question +-- +-- The object that describes a DNS question. +-- .SS Attributes +-- .TP +-- have_type +-- Set if there is a type. +-- .TP +-- have_class +-- Set if there is a class. +-- .TP +-- type +-- The type. +-- .TP +-- class +-- The class. +-- .TP +-- labels +-- The number of labels found in the question. +module(...,package.seeall) + +require("dnsjit.core.object.dns_h") +local ffi = require("ffi") + +local Q = {} + +-- Create a new question. +function Q.new(size) + return ffi.new("core_object_dns_q_t") +end + +-- dnsjit.core.object.dns (3) +return Q diff --git a/src/core/object/dns/rr.lua b/src/core/object/dns/rr.lua new file mode 100644 index 0000000..d360d96 --- /dev/null +++ b/src/core/object/dns/rr.lua @@ -0,0 +1,85 @@ +-- Copyright (c) 2018-2021, OARC, Inc. +-- All rights reserved. +-- +-- This file is part of dnsjit. +-- +-- dnsjit is free software: you can redistribute it and/or modify +-- it under the terms of the GNU General Public License as published by +-- the Free Software Foundation, either version 3 of the License, or +-- (at your option) any later version. +-- +-- dnsjit is distributed in the hope that it will be useful, +-- but WITHOUT ANY WARRANTY; without even the implied warranty of +-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +-- GNU General Public License for more details. +-- +-- You should have received a copy of the GNU General Public License +-- along with dnsjit. If not, see <http://www.gnu.org/licenses/>. + +-- dnsjit.core.object.dns.rr +-- Container of a DNS resource record +-- +-- The object that describes a DNS resource record. +-- .SS Attributes +-- .TP +-- have_type +-- Set if there is a type. +-- .TP +-- have_class +-- Set if there is a class. +-- .TP +-- have_ttl +-- Set if there is a ttl. +-- .TP +-- have_rdlength +-- Set if there is a rdlength. +-- .TP +-- have_rdata +-- Set if there is resource record data. +-- .TP +-- have_rdata_labels +-- Set if there are any labels within the rdata. +-- .TP +-- have_padding +-- Set if there is padding. +-- .TP +-- type +-- The type. +-- .TP +-- class +-- The class. +-- .TP +-- ttl +-- The TTL. +-- .TP +-- rdlength +-- The resource record data length. +-- .TP +-- labels +-- The number of labels found in the record. +-- .TP +-- rdata_offset +-- The offset within the payload for the resource record data. +-- .TP +-- rdata_labels +-- The number of labels found inside the resource record data. +-- .TP +-- padding_offset +-- The offset within the payload where the padding starts. +-- .TP +-- padding_length +-- The length of the padding. +module(...,package.seeall) + +require("dnsjit.core.object.dns_h") +local ffi = require("ffi") + +local Rr = {} + +-- Create a new resource record. +function Rr.new() + return ffi.new("core_object_dns_rr_t") +end + +-- dnsjit.core.object.dns (3) +return Rr |