/* $NetBSD: res_debug.c,v 1.13 2012/06/25 22:32:45 abs Exp $ */
/*
* Portions Copyright (C) 2004, 2005, 2008, 2009 Internet Systems Consortium, Inc. ("ISC")
* Portions Copyright (C) 1996-2003 Internet Software Consortium.
*
* 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.
*/
/*
* Copyright (c) 1985
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* Portions Copyright (c) 1993 by Digital Equipment Corporation.
*
* 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, and that
* the name of Digital Equipment Corporation not be used in advertising or
* publicity pertaining to distribution of the document or software without
* specific, written prior permission.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
* WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
* CORPORATION 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.
*/
/*
* Portions Copyright (c) 1995 by International Business Machines, Inc.
*
* International Business Machines, Inc. (hereinafter called IBM) grants
* permission under its copyrights to use, copy, modify, and distribute this
* Software with or without fee, provided that the above copyright notice and
* all paragraphs of this notice appear in all copies, and that the name of IBM
* not be used in connection with the marketing of any product incorporating
* the Software or modifications thereof, without specific, written prior
* permission.
*
* To the extent it has a right to do so, IBM grants an immunity from suit
* under its patents, if any, for the use, sale or manufacture of products to
* the extent that such products are used for performing Domain Name System
* dynamic updates in TCP/IP networks by means of the Software. No immunity is
* granted for any product per se or for any other function of any product.
*
* THE SOFTWARE IS PROVIDED "AS IS", AND IBM DISCLAIMS ALL WARRANTIES,
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE. IN NO EVENT SHALL IBM BE LIABLE FOR ANY SPECIAL,
* DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER ARISING
* OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE, EVEN
* IF IBM IS APPRISED OF THE POSSIBILITY OF SUCH DAMAGES.
*/
#define LOG_TAG "res_debug"
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>
#include <netinet/in.h>
#include <aidl/android/net/IDnsResolver.h>
#include <android-base/logging.h>
#include <ctype.h>
#include <errno.h>
#include <math.h>
#include <netdb.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <time.h>
#include "resolv_private.h"
// Default to disabling verbose logging unless overridden by Android.bp
// for debuggable builds.
//
// NOTE: Verbose resolver logs could contain PII -- do NOT enable in production builds
#ifndef RESOLV_ALLOW_VERBOSE_LOGGING
#define RESOLV_ALLOW_VERBOSE_LOGGING 0
#endif
struct res_sym {
int number; /* Identifying number, like T_MX */
const char* name; /* Its symbolic name, like "MX" */
const char* humanname; /* Its fun name, like "mail exchanger" */
};
// add a formatted string to a bounded buffer
// TODO: convert to std::string
static char* dbprint(char* p, char* end, const char* format, ...) {
int avail, n;
va_list args;
avail = end - p;
if (avail <= 0) return p;
va_start(args, format);
n = vsnprintf(p, avail, format, args);
va_end(args);
/* certain C libraries return -1 in case of truncation */
if (n < 0 || n > avail) n = avail;
p += n;
/* certain C libraries do not zero-terminate in case of truncation */
if (p == end) p[-1] = 0;
return p;
}
static void do_section(ns_msg* handle, ns_sect section) {
int n, rrnum;
int buflen = 2048;
ns_opcode opcode;
ns_rr rr;
char temp[2048], *p = temp, *end = p + sizeof(temp);
/*
* Print answer records.
*/
char* buf = (char*) malloc((size_t) buflen);
if (buf == NULL) {
dbprint(p, end, ";; memory allocation failure\n");
LOG(VERBOSE) << __func__ << ": " << temp;
return;
}
opcode = (ns_opcode) ns_msg_getflag(*handle, ns_f_opcode);
rrnum = 0;
for (;;) {
if (ns_parserr(handle, section, rrnum, &rr)) {
if (errno != ENODEV)
dbprint(p, end, ";; ns_parserr: %s", strerror(errno));
goto cleanup;
}
if (section == ns_s_qd)
dbprint(p, end, ";;\t%s, type = %s, class = %s\n", ns_rr_name(rr),
p_type(ns_rr_type(rr)), p_class(ns_rr_class(rr)));
else if (section == ns_s_ar && ns_rr_type(rr) == ns_t_opt) {
size_t rdatalen, ttl;
uint16_t optcode, optlen;
rdatalen = ns_rr_rdlen(rr);
ttl = ns_rr_ttl(rr);
dbprint(p, end, "; EDNS: version: %zu, udp=%u, flags=%04zx\n", (ttl >> 16) & 0xff,
ns_rr_class(rr), ttl & 0xffff);
const u_char* cp = ns_rr_rdata(rr);
while (rdatalen <= ns_rr_rdlen(rr) && rdatalen >= 4) {
int i;
GETSHORT(optcode, cp);
GETSHORT(optlen, cp);
if (optcode == NS_OPT_NSID) {
p = dbprint(p, end, "; NSID: ");
if (optlen == 0) {
p = dbprint(p, end, "; NSID\n");
} else {
p = dbprint(p, end, "; NSID: ");
for (i = 0; i < optlen; i++) {
p = dbprint(p, end, "%02x ", cp[i]);
}
p = dbprint(p, end, " (");
for (i = 0; i < optlen; i++) {
p = dbprint(p, end, "%c", isprint(cp[i]) ? cp[i] : '.');
}
p = dbprint(p, end, ")\n");
}
} else {
if (optlen == 0) {
p = dbprint(p, end, "; OPT=%u\n", optcode);
} else {
p = dbprint(p, end, "; OPT=%u: ", optcode);
for (i = 0; i < optlen; i++) {
p = dbprint(p, end, "%02x ", cp[i]);
}
p = dbprint(p, end, " (");
for (i = 0; i < optlen; i++) {
p = dbprint(p, end, "%c", isprint(cp[i]) ? cp[i] : '.');
}
p = dbprint(p, end, ")\n");
}
}
rdatalen -= 4 + optlen;
cp += optlen;
}
} else {
n = ns_sprintrr(handle, &rr, NULL, NULL, buf, (u_int) buflen);
if (n < 0) {
if (errno == ENOSPC) {
free(buf);
buf = NULL;
if (buflen < 131072) {
buf = (char*) malloc((size_t)(buflen += 1024));
}
if (buf == NULL) {
p = dbprint(p, end, ";; memory allocation failure\n");
LOG(VERBOSE) << __func__ << ": " << temp;
return;
}
continue;
}
p = dbprint(p, end, ";; ns_sprintrr: %s\n", strerror(errno));
goto cleanup;
}
p = dbprint(p, end, ";; %s\n", buf);
}
rrnum++;
}
cleanup:
free(buf);
LOG(VERBOSE) << temp;
}
/*
* Print the contents of a query.
* This is intended to be primarily a debugging routine.
*/
void res_pquery(const u_char* msg, int len) {
if (!WOULD_LOG(VERBOSE)) return;
ns_msg handle;
int qdcount, ancount, nscount, arcount;
u_int opcode, rcode, id;
char temp[2048], *p = temp, *end = p + sizeof(temp);
if (ns_initparse(msg, len, &handle) < 0) {
dbprint(p, end, ";; ns_initparse: %s\n", strerror(errno));
return;
}
opcode = ns_msg_getflag(handle, ns_f_opcode);
rcode = ns_msg_getflag(handle, ns_f_rcode);
id = ns_msg_id(handle);
qdcount = ns_msg_count(handle, ns_s_qd);
ancount = ns_msg_count(handle, ns_s_an);
nscount = ns_msg_count(handle, ns_s_ns);
arcount = ns_msg_count(handle, ns_s_ar);
/*
* Print header fields.
*/
dbprint(p, end, ";; ->>HEADER<<- opcode: %s, status: %s, id: %d\n", _res_opcodes[opcode],
p_rcode((int)rcode), id);
p = dbprint(p, end, ";");
p = dbprint(p, end, "; flags:");
if (ns_msg_getflag(handle, ns_f_qr)) p = dbprint(p, end, " qr");
if (ns_msg_getflag(handle, ns_f_aa)) p = dbprint(p, end, " aa");
if (ns_msg_getflag(handle, ns_f_tc)) p = dbprint(p, end, " tc");
if (ns_msg_getflag(handle, ns_f_rd)) p = dbprint(p, end, " rd");
if (ns_msg_getflag(handle, ns_f_ra)) p = dbprint(p, end, " ra");
if (ns_msg_getflag(handle, ns_f_z)) p = dbprint(p, end, " ??");
if (ns_msg_getflag(handle, ns_f_ad)) p = dbprint(p, end, " ad");
if (ns_msg_getflag(handle, ns_f_cd)) p = dbprint(p, end, " cd");
p = dbprint(p, end, "; %s: %d", p_section(ns_s_qd, (int)opcode), qdcount);
p = dbprint(p, end, ", %s: %d", p_section(ns_s_an, (int)opcode), ancount);
p = dbprint(p, end, ", %s: %d", p_section(ns_s_ns, (int)opcode), nscount);
p = dbprint(p, end, ", %s: %d", p_section(ns_s_ar, (int)opcode), arcount);
LOG(VERBOSE) << temp;
/*
* Print the various sections.
*/
do_section(&handle, ns_s_qd);
do_section(&handle, ns_s_an);
do_section(&handle, ns_s_ns);
do_section(&handle, ns_s_ar);
if (qdcount == 0 && ancount == 0 && nscount == 0 && arcount == 0) LOG(VERBOSE) << ";;";
}
/*
* Names of RR classes and qclasses. Classes and qclasses are the same, except
* that C_ANY is a qclass but not a class. (You can ask for records of class
* C_ANY, but you can't have any records of that class in the database.)
*/
static const struct res_sym p_class_syms[] = {
{C_IN, "IN", (char*) 0}, {C_CHAOS, "CH", (char*) 0}, {C_CHAOS, "CHAOS", (char*) 0},
{C_HS, "HS", (char*) 0}, {C_HS, "HESIOD", (char*) 0}, {C_ANY, "ANY", (char*) 0},
{C_NONE, "NONE", (char*) 0}, {C_IN, (char*) 0, (char*) 0}};
/*
* Names of message sections.
*/
static const struct res_sym p_default_section_syms[] = {{ns_s_qd, "QUERY", (char*) 0},
{ns_s_an, "ANSWER", (char*) 0},
{ns_s_ns, "AUTHORITY", (char*) 0},
{ns_s_ar, "ADDITIONAL", (char*) 0},
{0, (char*) 0, (char*) 0}};
static const struct res_sym p_update_section_syms[] = {{S_ZONE, "ZONE", (char*) 0},
{S_PREREQ, "PREREQUISITE", (char*) 0},
{S_UPDATE, "UPDATE", (char*) 0},
{S_ADDT, "ADDITIONAL", (char*) 0},
{0, (char*) 0, (char*) 0}};
/*
* Names of RR types and qtypes. Types and qtypes are the same, except
* that T_ANY is a qtype but not a type. (You can ask for records of type
* T_ANY, but you can't have any records of that type in the database.)
*/
const struct res_sym p_type_syms[] = {
{ns_t_a, "A", "address"},
{ns_t_ns, "NS", "name server"},
{ns_t_md, "MD", "mail destination (deprecated)"},
{ns_t_mf, "MF", "mail forwarder (deprecated)"},
{ns_t_cname, "CNAME", "canonical name"},
{ns_t_soa, "SOA", "start of authority"},
{ns_t_mb, "MB", "mailbox"},
{ns_t_mg, "MG", "mail group member"},
{ns_t_mr, "MR", "mail rename"},
{ns_t_null, "NULL", "null"},
{ns_t_wks, "WKS", "well-known service (deprecated)"},
{ns_t_ptr, "PTR", "domain name pointer"},
{ns_t_hinfo, "HINFO", "host information"},
{ns_t_minfo, "MINFO", "mailbox information"},
{ns_t_mx, "MX", "mail exchanger"},
{ns_t_txt, "TXT", "text"},
{ns_t_rp, "RP", "responsible person"},
{ns_t_afsdb, "AFSDB", "DCE or AFS server"},
{ns_t_x25, "X25", "X25 address"},
{ns_t_isdn, "ISDN", "ISDN address"},
{ns_t_rt, "RT", "router"},
{ns_t_nsap, "NSAP", "nsap address"},
{ns_t_nsap_ptr, "NSAP_PTR", "domain name pointer"},
{ns_t_sig, "SIG", "signature"},
{ns_t_key, "KEY", "key"},
{ns_t_px, "PX", "mapping information"},
{ns_t_gpos, "GPOS", "geographical position (withdrawn)"},
{ns_t_aaaa, "AAAA", "IPv6 address"},
{ns_t_loc, "LOC", "location"},
{ns_t_nxt, "NXT", "next valid name (unimplemented)"},
{ns_t_eid, "EID", "endpoint identifier (unimplemented)"},
{ns_t_nimloc, "NIMLOC", "NIMROD locator (unimplemented)"},
{ns_t_srv, "SRV", "server selection"},
{ns_t_atma, "ATMA", "ATM address (unimplemented)"},
{ns_t_naptr, "NAPTR", "naptr"},
{ns_t_kx, "KX", "key exchange"},
{ns_t_cert, "CERT", "certificate"},
{ns_t_a6, "A", "IPv6 address (experminental)"},
{ns_t_dname, "DNAME", "non-terminal redirection"},
{ns_t_opt, "OPT", "opt"},
{ns_t_apl, "apl", "apl"},
{ns_t_ds, "DS", "delegation signer"},
{ns_t_sshfp, "SSFP", "SSH fingerprint"},
{ns_t_ipseckey, "IPSECKEY", "IPSEC key"},
{ns_t_rrsig, "RRSIG", "rrsig"},
{ns_t_nsec, "NSEC", "nsec"},
{ns_t_dnskey, "DNSKEY", "DNS key"},
{ns_t_dhcid, "DHCID", "dynamic host configuration identifier"},
{ns_t_nsec3, "NSEC3", "nsec3"},
{ns_t_nsec3param, "NSEC3PARAM", "NSEC3 parameters"},
{ns_t_hip, "HIP", "host identity protocol"},
{ns_t_spf, "SPF", "sender policy framework"},
{ns_t_tkey, "TKEY", "tkey"},
{ns_t_tsig, "TSIG", "transaction signature"},
{ns_t_ixfr, "IXFR", "incremental zone transfer"},
{ns_t_axfr, "AXFR", "zone transfer"},
{ns_t_zxfr, "ZXFR", "compressed zone transfer"},
{ns_t_mailb, "MAILB", "mailbox-related data (deprecated)"},
{ns_t_maila, "MAILA", "mail agent (deprecated)"},
{ns_t_naptr, "NAPTR", "URN Naming Authority"},
{ns_t_kx, "KX", "Key Exchange"},
{ns_t_cert, "CERT", "Certificate"},
{ns_t_a6, "A6", "IPv6 Address"},
{ns_t_dname, "DNAME", "dname"},
{ns_t_sink, "SINK", "Kitchen Sink (experimental)"},
{ns_t_opt, "OPT", "EDNS Options"},
{ns_t_any, "ANY", "\"any\""},
{ns_t_dlv, "DLV", "DNSSEC look-aside validation"},
{0, NULL, NULL}};
/*
* Names of DNS rcodes.
*/
static const struct res_sym p_rcode_syms[] = {{ns_r_noerror, "NOERROR", "no error"},
{ns_r_formerr, "FORMERR", "format error"},
{ns_r_servfail, "SERVFAIL", "server failed"},
{ns_r_nxdomain, "NXDOMAIN", "no such domain name"},
{ns_r_notimpl, "NOTIMP", "not implemented"},
{ns_r_refused, "REFUSED", "refused"},
{ns_r_yxdomain, "YXDOMAIN", "domain name exists"},
{ns_r_yxrrset, "YXRRSET", "rrset exists"},
{ns_r_nxrrset, "NXRRSET", "rrset doesn't exist"},
{ns_r_notauth, "NOTAUTH", "not authoritative"},
{ns_r_notzone, "NOTZONE", "Not in zone"},
{ns_r_max, "", ""},
{ns_r_badsig, "BADSIG", "bad signature"},
{ns_r_badkey, "BADKEY", "bad key"},
{ns_r_badtime, "BADTIME", "bad time"},
{0, NULL, NULL}};
static const char* sym_ntos(const struct res_sym* syms, int number, int* success) {
static char unname[20];
for (; syms->name != 0; syms++) {
if (number == syms->number) {
if (success) *success = 1;
return (syms->name);
}
}
snprintf(unname, sizeof(unname), "%d", number); /* XXX nonreentrant */
if (success) *success = 0;
return (unname);
}
/*
* Return a string for the type.
*/
const char* p_type(int type) {
int success;
const char* result;
static char typebuf[20];
result = sym_ntos(p_type_syms, type, &success);
if (success) return (result);
if (type < 0 || type > 0xffff) return ("BADTYPE");
snprintf(typebuf, sizeof(typebuf), "TYPE%d", type);
return (typebuf);
}
/*
* Return a string for the type.
*/
const char* p_section(int section, int opcode) {
const struct res_sym* symbols;
switch (opcode) {
case ns_o_update:
symbols = p_update_section_syms;
break;
default:
symbols = p_default_section_syms;
break;
}
return (sym_ntos(symbols, section, (int*) 0));
}
/*
* Return a mnemonic for class.
*/
const char* p_class(int cl) {
int success;
const char* result;
static char classbuf[20];
result = sym_ntos(p_class_syms, cl, &success);
if (success) return (result);
if (cl < 0 || cl > 0xffff) return ("BADCLASS");
snprintf(classbuf, sizeof(classbuf), "CLASS%d", cl);
return (classbuf);
}
/*
* Return a string for the rcode.
*/
const char* p_rcode(int rcode) {
return (sym_ntos(p_rcode_syms, rcode, (int*) 0));
}
int resolv_set_log_severity(uint32_t logSeverity) {
switch (logSeverity) {
case aidl::android::net::IDnsResolver::DNS_RESOLVER_LOG_VERBOSE:
logSeverity = android::base::VERBOSE;
// *** enable verbose logging only when DBG is set. It prints sensitive data ***
if (RESOLV_ALLOW_VERBOSE_LOGGING == false) {
logSeverity = android::base::DEBUG;
LOG(ERROR) << "Refusing to set VERBOSE logging in non-debuggable build";
// TODO: Return EACCES then callers could know if the log
// severity is acceptable
}
break;
case aidl::android::net::IDnsResolver::DNS_RESOLVER_LOG_DEBUG:
logSeverity = android::base::DEBUG;
break;
case aidl::android::net::IDnsResolver::DNS_RESOLVER_LOG_INFO:
logSeverity = android::base::INFO;
break;
case aidl::android::net::IDnsResolver::DNS_RESOLVER_LOG_WARNING:
logSeverity = android::base::WARNING;
break;
case aidl::android::net::IDnsResolver::DNS_RESOLVER_LOG_ERROR:
logSeverity = android::base::ERROR;
break;
default:
LOG(ERROR) << __func__ << ": invalid log severity: " << logSeverity;
return -EINVAL;
}
android::base::SetMinimumLogSeverity(static_cast<android::base::LogSeverity>(logSeverity));
return 0;
}