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monero/external/unbound/ldns/wire2str.c
Riccardo Spagni 9ef094b356
added unbound to external deps
2014-10-05 23:44:31 +02:00

1967 lines
54 KiB
C
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/*
* wire2str.c
*
* conversion routines from the wire format
* to the presentation format (strings)
*
* (c) NLnet Labs, 2004-2006
*
* See the file LICENSE for the license
*/
/**
* \file
*
* Contains functions to translate the wireformat to text
* representation, as well as functions to print them.
*/
#include "config.h"
#include "ldns/wire2str.h"
#include "ldns/str2wire.h"
#include "ldns/rrdef.h"
#include "ldns/pkthdr.h"
#include "ldns/parseutil.h"
#include "ldns/sbuffer.h"
#include "ldns/keyraw.h"
#ifdef HAVE_TIME_H
#include <time.h>
#endif
#include <sys/time.h>
#include <stdarg.h>
#include <ctype.h>
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
/* lookup tables for standard DNS stuff */
/* Taken from RFC 2535, section 7. */
static sldns_lookup_table sldns_algorithms_data[] = {
{ LDNS_RSAMD5, "RSAMD5" },
{ LDNS_DH, "DH" },
{ LDNS_DSA, "DSA" },
{ LDNS_ECC, "ECC" },
{ LDNS_RSASHA1, "RSASHA1" },
{ LDNS_DSA_NSEC3, "DSA-NSEC3-SHA1" },
{ LDNS_RSASHA1_NSEC3, "RSASHA1-NSEC3-SHA1" },
{ LDNS_RSASHA256, "RSASHA256"},
{ LDNS_RSASHA512, "RSASHA512"},
{ LDNS_ECC_GOST, "ECC-GOST"},
{ LDNS_ECDSAP256SHA256, "ECDSAP256SHA256"},
{ LDNS_ECDSAP384SHA384, "ECDSAP384SHA384"},
{ LDNS_INDIRECT, "INDIRECT" },
{ LDNS_PRIVATEDNS, "PRIVATEDNS" },
{ LDNS_PRIVATEOID, "PRIVATEOID" },
{ 0, NULL }
};
sldns_lookup_table* sldns_algorithms = sldns_algorithms_data;
/* hash algorithms in DS record */
static sldns_lookup_table sldns_hashes_data[] = {
{ LDNS_SHA1, "SHA1" },
{ LDNS_SHA256, "SHA256" },
{ LDNS_HASH_GOST, "HASH-GOST" },
{ LDNS_SHA384, "SHA384" },
{ 0, NULL }
};
sldns_lookup_table* sldns_hashes = sldns_hashes_data;
/* Taken from RFC 4398 */
static sldns_lookup_table sldns_cert_algorithms_data[] = {
{ LDNS_CERT_PKIX, "PKIX" },
{ LDNS_CERT_SPKI, "SPKI" },
{ LDNS_CERT_PGP, "PGP" },
{ LDNS_CERT_IPKIX, "IPKIX" },
{ LDNS_CERT_ISPKI, "ISPKI" },
{ LDNS_CERT_IPGP, "IPGP" },
{ LDNS_CERT_ACPKIX, "ACPKIX" },
{ LDNS_CERT_IACPKIX, "IACPKIX" },
{ LDNS_CERT_URI, "URI" },
{ LDNS_CERT_OID, "OID" },
{ 0, NULL }
};
sldns_lookup_table* sldns_cert_algorithms = sldns_cert_algorithms_data;
/* if these are used elsewhere */
static sldns_lookup_table sldns_rcodes_data[] = {
{ LDNS_RCODE_NOERROR, "NOERROR" },
{ LDNS_RCODE_FORMERR, "FORMERR" },
{ LDNS_RCODE_SERVFAIL, "SERVFAIL" },
{ LDNS_RCODE_NXDOMAIN, "NXDOMAIN" },
{ LDNS_RCODE_NOTIMPL, "NOTIMPL" },
{ LDNS_RCODE_REFUSED, "REFUSED" },
{ LDNS_RCODE_YXDOMAIN, "YXDOMAIN" },
{ LDNS_RCODE_YXRRSET, "YXRRSET" },
{ LDNS_RCODE_NXRRSET, "NXRRSET" },
{ LDNS_RCODE_NOTAUTH, "NOTAUTH" },
{ LDNS_RCODE_NOTZONE, "NOTZONE" },
{ 0, NULL }
};
sldns_lookup_table* sldns_rcodes = sldns_rcodes_data;
static sldns_lookup_table sldns_opcodes_data[] = {
{ LDNS_PACKET_QUERY, "QUERY" },
{ LDNS_PACKET_IQUERY, "IQUERY" },
{ LDNS_PACKET_STATUS, "STATUS" },
{ LDNS_PACKET_NOTIFY, "NOTIFY" },
{ LDNS_PACKET_UPDATE, "UPDATE" },
{ 0, NULL }
};
sldns_lookup_table* sldns_opcodes = sldns_opcodes_data;
static sldns_lookup_table sldns_wireparse_errors_data[] = {
{ LDNS_WIREPARSE_ERR_OK, "no parse error" },
{ LDNS_WIREPARSE_ERR_GENERAL, "parse error" },
{ LDNS_WIREPARSE_ERR_DOMAINNAME_OVERFLOW, "Domainname length overflow" },
{ LDNS_WIREPARSE_ERR_DOMAINNAME_UNDERFLOW, "Domainname length underflow (zero length)" },
{ LDNS_WIREPARSE_ERR_BUFFER_TOO_SMALL, "buffer too small" },
{ LDNS_WIREPARSE_ERR_LABEL_OVERFLOW, "Label length overflow" },
{ LDNS_WIREPARSE_ERR_EMPTY_LABEL, "Empty label" },
{ LDNS_WIREPARSE_ERR_SYNTAX_BAD_ESCAPE, "Syntax error, bad escape sequence" },
{ LDNS_WIREPARSE_ERR_SYNTAX, "Syntax error, could not parse the RR" },
{ LDNS_WIREPARSE_ERR_SYNTAX_TTL, "Syntax error, could not parse the RR's TTL" },
{ LDNS_WIREPARSE_ERR_SYNTAX_TYPE, "Syntax error, could not parse the RR's type" },
{ LDNS_WIREPARSE_ERR_SYNTAX_CLASS, "Syntax error, could not parse the RR's class" },
{ LDNS_WIREPARSE_ERR_SYNTAX_RDATA, "Syntax error, could not parse the RR's rdata" },
{ LDNS_WIREPARSE_ERR_SYNTAX_MISSING_VALUE, "Syntax error, value expected" },
{ LDNS_WIREPARSE_ERR_INVALID_STR, "Conversion error, string expected" },
{ LDNS_WIREPARSE_ERR_SYNTAX_B64, "Conversion error, b64 encoding expected" },
{ LDNS_WIREPARSE_ERR_SYNTAX_B32_EXT, "Conversion error, b32 ext encoding expected" },
{ LDNS_WIREPARSE_ERR_SYNTAX_HEX, "Conversion error, hex encoding expected" },
{ LDNS_WIREPARSE_ERR_CERT_BAD_ALGORITHM, "Bad algorithm type for CERT record" },
{ LDNS_WIREPARSE_ERR_SYNTAX_TIME, "Conversion error, time encoding expected" },
{ LDNS_WIREPARSE_ERR_SYNTAX_PERIOD, "Conversion error, time period encoding expected" },
{ LDNS_WIREPARSE_ERR_SYNTAX_ILNP64, "Conversion error, 4 colon separated hex numbers expected" },
{ LDNS_WIREPARSE_ERR_SYNTAX_EUI48,
"Conversion error, 6 two character hex numbers "
"separated by dashes expected (i.e. xx-xx-xx-xx-xx-xx" },
{ LDNS_WIREPARSE_ERR_SYNTAX_EUI64,
"Conversion error, 8 two character hex numbers "
"separated by dashes expected (i.e. xx-xx-xx-xx-xx-xx-xx-xx" },
{ LDNS_WIREPARSE_ERR_SYNTAX_TAG,
"Conversion error, a non-zero sequence of US-ASCII letters "
"and numbers in lower case expected" },
{ LDNS_WIREPARSE_ERR_NOT_IMPL, "not implemented" },
{ LDNS_WIREPARSE_ERR_SYNTAX_INT, "Conversion error, integer expected" },
{ LDNS_WIREPARSE_ERR_SYNTAX_IP4, "Conversion error, ip4 addr expected" },
{ LDNS_WIREPARSE_ERR_SYNTAX_IP6, "Conversion error, ip6 addr expected" },
{ LDNS_WIREPARSE_ERR_SYNTAX_INTEGER_OVERFLOW, "Syntax error, integer overflow" },
{ LDNS_WIREPARSE_ERR_INCLUDE, "$INCLUDE directive was seen in the zone" },
{ LDNS_WIREPARSE_ERR_PARENTHESIS, "Parse error, parenthesis mismatch" },
{ 0, NULL }
};
sldns_lookup_table* sldns_wireparse_errors = sldns_wireparse_errors_data;
static sldns_lookup_table sldns_edns_flags_data[] = {
{ 3600, "do"},
{ 0, NULL}
};
sldns_lookup_table* sldns_edns_flags = sldns_edns_flags_data;
static sldns_lookup_table sldns_edns_options_data[] = {
{ 1, "LLQ" },
{ 2, "UL" },
{ 3, "NSID" },
/* 4 draft-cheshire-edns0-owner-option */
{ 5, "DAU" },
{ 6, "DHU" },
{ 7, "N3U" },
{ 8, "edns-client-subnet" },
{ 0, NULL}
};
sldns_lookup_table* sldns_edns_options = sldns_edns_options_data;
char* sldns_wire2str_pkt(uint8_t* data, size_t len)
{
size_t slen = (size_t)sldns_wire2str_pkt_buf(data, len, NULL, 0);
char* result = (char*)malloc(slen+1);
if(!result) return NULL;
sldns_wire2str_pkt_buf(data, len, result, slen+1);
return result;
}
char* sldns_wire2str_rr(uint8_t* rr, size_t len)
{
size_t slen = (size_t)sldns_wire2str_rr_buf(rr, len, NULL, 0);
char* result = (char*)malloc(slen+1);
if(!result) return NULL;
sldns_wire2str_rr_buf(rr, len, result, slen+1);
return result;
}
char* sldns_wire2str_type(uint16_t rrtype)
{
char buf[16];
sldns_wire2str_type_buf(rrtype, buf, sizeof(buf));
return strdup(buf);
}
char* sldns_wire2str_class(uint16_t rrclass)
{
char buf[16];
sldns_wire2str_class_buf(rrclass, buf, sizeof(buf));
return strdup(buf);
}
char* sldns_wire2str_dname(uint8_t* dname, size_t dname_len)
{
size_t slen=(size_t)sldns_wire2str_dname_buf(dname, dname_len, NULL, 0);
char* result = (char*)malloc(slen+1);
if(!result) return NULL;
sldns_wire2str_dname_buf(dname, dname_len, result, slen+1);
return result;
}
char* sldns_wire2str_rcode(int rcode)
{
char buf[16];
sldns_wire2str_rcode_buf(rcode, buf, sizeof(buf));
return strdup(buf);
}
int sldns_wire2str_pkt_buf(uint8_t* d, size_t dlen, char* s, size_t slen)
{
/* use arguments as temporary variables */
return sldns_wire2str_pkt_scan(&d, &dlen, &s, &slen);
}
int sldns_wire2str_rr_buf(uint8_t* d, size_t dlen, char* s, size_t slen)
{
/* use arguments as temporary variables */
return sldns_wire2str_rr_scan(&d, &dlen, &s, &slen, NULL, 0);
}
int sldns_wire2str_rdata_buf(uint8_t* rdata, size_t rdata_len, char* str,
size_t str_len, uint16_t rrtype)
{
/* use arguments as temporary variables */
return sldns_wire2str_rdata_scan(&rdata, &rdata_len, &str, &str_len,
rrtype, NULL, 0);
}
int sldns_wire2str_rr_unknown_buf(uint8_t* d, size_t dlen, char* s, size_t slen)
{
/* use arguments as temporary variables */
return sldns_wire2str_rr_unknown_scan(&d, &dlen, &s, &slen, NULL, 0);
}
int sldns_wire2str_rr_comment_buf(uint8_t* rr, size_t rrlen, size_t dname_len,
char* s, size_t slen)
{
uint16_t rrtype = sldns_wirerr_get_type(rr, rrlen, dname_len);
return sldns_wire2str_rr_comment_print(&s, &slen, rr, rrlen, dname_len,
rrtype);
}
int sldns_wire2str_type_buf(uint16_t rrtype, char* s, size_t slen)
{
/* use arguments as temporary variables */
return sldns_wire2str_type_print(&s, &slen, rrtype);
}
int sldns_wire2str_class_buf(uint16_t rrclass, char* s, size_t slen)
{
/* use arguments as temporary variables */
return sldns_wire2str_class_print(&s, &slen, rrclass);
}
int sldns_wire2str_rcode_buf(int rcode, char* s, size_t slen)
{
/* use arguments as temporary variables */
return sldns_wire2str_rcode_print(&s, &slen, rcode);
}
int sldns_wire2str_dname_buf(uint8_t* d, size_t dlen, char* s, size_t slen)
{
/* use arguments as temporary variables */
return sldns_wire2str_dname_scan(&d, &dlen, &s, &slen, NULL, 0);
}
int sldns_str_vprint(char** str, size_t* slen, const char* format, va_list args)
{
int w = vsnprintf(*str, *slen, format, args);
if(w < 0) {
/* error in printout */
return 0;
} else if((size_t)w >= *slen) {
*str = NULL; /* we do not want str to point outside of buffer*/
*slen = 0;
} else {
*str += w;
*slen -= w;
}
return w;
}
int sldns_str_print(char** str, size_t* slen, const char* format, ...)
{
int w;
va_list args;
va_start(args, format);
w = sldns_str_vprint(str, slen, format, args);
va_end(args);
return w;
}
/** print hex format into text buffer for specified length */
static int print_hex_buf(char** s, size_t* slen, uint8_t* buf, size_t len)
{
const char* hex = "0123456789ABCDEF";
size_t i;
for(i=0; i<len; i++) {
(void)sldns_str_print(s, slen, "%c%c", hex[(buf[i]&0xf0)>>4],
hex[buf[i]&0x0f]);
}
return (int)len*2;
}
/** print remainder of buffer in hex format with prefixed text */
static int print_remainder_hex(const char* pref, uint8_t** d, size_t* dlen,
char** s, size_t* slen)
{
int w = 0;
w += sldns_str_print(s, slen, "%s", pref);
w += print_hex_buf(s, slen, *d, *dlen);
*d += *dlen;
*dlen = 0;
return w;
}
int sldns_wire2str_pkt_scan(uint8_t** d, size_t* dlen, char** s, size_t* slen)
{
int w = 0;
unsigned qdcount, ancount, nscount, arcount, i;
uint8_t* pkt = *d;
size_t pktlen = *dlen;
if(*dlen >= LDNS_HEADER_SIZE) {
qdcount = (unsigned)LDNS_QDCOUNT(*d);
ancount = (unsigned)LDNS_ANCOUNT(*d);
nscount = (unsigned)LDNS_NSCOUNT(*d);
arcount = (unsigned)LDNS_ARCOUNT(*d);
} else {
qdcount = ancount = nscount = arcount = 0;
}
w += sldns_wire2str_header_scan(d, dlen, s, slen);
w += sldns_str_print(s, slen, "\n");
w += sldns_str_print(s, slen, ";; QUESTION SECTION:\n");
for(i=0; i<qdcount; i++) {
w += sldns_wire2str_rrquestion_scan(d, dlen, s, slen,
pkt, pktlen);
if(!*dlen) break;
}
w += sldns_str_print(s, slen, "\n");
w += sldns_str_print(s, slen, ";; ANSWER SECTION:\n");
for(i=0; i<ancount; i++) {
w += sldns_wire2str_rr_scan(d, dlen, s, slen, pkt, pktlen);
if(!*dlen) break;
}
w += sldns_str_print(s, slen, "\n");
w += sldns_str_print(s, slen, ";; AUTHORITY SECTION:\n");
for(i=0; i<nscount; i++) {
w += sldns_wire2str_rr_scan(d, dlen, s, slen, pkt, pktlen);
if(!*dlen) break;
}
w += sldns_str_print(s, slen, "\n");
w += sldns_str_print(s, slen, ";; ADDITIONAL SECTION:\n");
for(i=0; i<arcount; i++) {
w += sldns_wire2str_rr_scan(d, dlen, s, slen, pkt, pktlen);
if(!*dlen) break;
}
/* other fields: WHEN(time), SERVER(IP) not available here. */
w += sldns_str_print(s, slen, ";; MSG SIZE rcvd: %d\n", (int)pktlen);
if(*dlen > 0) {
w += print_remainder_hex(";; trailing garbage 0x",
d, dlen, s, slen);
w += sldns_str_print(s, slen, "\n");
}
return w;
}
/** scan type, class and ttl and printout, for rr */
static int sldns_rr_tcttl_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
int w = 0;
uint16_t t, c;
uint32_t ttl;
if(*dl < 8) {
if(*dl < 4)
return w + print_remainder_hex("; Error malformed 0x",
d, dl, s, sl);
/* these print values or 0x.. if none left */
t = sldns_read_uint16(*d);
c = sldns_read_uint16((*d)+2);
(*d)+=4;
(*dl)-=4;
w += sldns_wire2str_class_print(s, sl, c);
w += sldns_str_print(s, sl, "\t");
w += sldns_wire2str_type_print(s, sl, t);
if(*dl == 0)
return w + sldns_str_print(s, sl, "; Error no ttl");
return w + print_remainder_hex(
"; Error malformed ttl 0x", d, dl, s, sl);
}
t = sldns_read_uint16(*d);
c = sldns_read_uint16((*d)+2);
ttl = sldns_read_uint32((*d)+4);
(*d)+=8;
(*dl)-=8;
w += sldns_str_print(s, sl, "%lu\t", (unsigned long)ttl);
w += sldns_wire2str_class_print(s, sl, c);
w += sldns_str_print(s, sl, "\t");
w += sldns_wire2str_type_print(s, sl, t);
return w;
}
int sldns_wire2str_rr_scan(uint8_t** d, size_t* dlen, char** s, size_t* slen,
uint8_t* pkt, size_t pktlen)
{
int w = 0;
uint8_t* rr = *d;
size_t rrlen = *dlen, dname_off, rdlen, ordlen;
uint16_t rrtype = 0;
if(*dlen >= 3 && (*d)[0]==0 &&
sldns_read_uint16((*d)+1)==LDNS_RR_TYPE_OPT) {
/* perform EDNS OPT processing */
return sldns_wire2str_edns_scan(d, dlen, s, slen, pkt, pktlen);
}
/* try to scan the rdata with pretty-printing, but if that fails, then
* scan the rdata as an unknown RR type */
w += sldns_wire2str_dname_scan(d, dlen, s, slen, pkt, pktlen);
w += sldns_str_print(s, slen, "\t");
dname_off = rrlen-(*dlen);
if(*dlen == 4) {
/* like a question-RR */
uint16_t t = sldns_read_uint16(*d);
uint16_t c = sldns_read_uint16((*d)+2);
(*d)+=4;
(*dlen)-=4;
w += sldns_wire2str_class_print(s, slen, c);
w += sldns_str_print(s, slen, "\t");
w += sldns_wire2str_type_print(s, slen, t);
w += sldns_str_print(s, slen, " ; Error no ttl,rdata\n");
return w;
}
if(*dlen < 8) {
if(*dlen == 0)
return w + sldns_str_print(s, slen, ";Error missing RR\n");
w += print_remainder_hex(";Error partial RR 0x", d, dlen, s, slen);
return w + sldns_str_print(s, slen, "\n");
}
rrtype = sldns_read_uint16(*d);
w += sldns_rr_tcttl_scan(d, dlen, s, slen);
w += sldns_str_print(s, slen, "\t");
/* rdata */
if(*dlen < 2) {
if(*dlen == 0)
return w + sldns_str_print(s, slen, ";Error missing rdatalen\n");
w += print_remainder_hex(";Error missing rdatalen 0x",
d, dlen, s, slen);
return w + sldns_str_print(s, slen, "\n");
}
rdlen = sldns_read_uint16(*d);
ordlen = rdlen;
(*d)+=2;
(*dlen)-=2;
if(*dlen < rdlen) {
w += sldns_str_print(s, slen, "\\# %u ", (unsigned)rdlen);
if(*dlen == 0)
return w + sldns_str_print(s, slen, ";Error missing rdata\n");
w += print_remainder_hex(";Error partial rdata 0x", d, dlen, s, slen);
return w + sldns_str_print(s, slen, "\n");
}
w += sldns_wire2str_rdata_scan(d, &rdlen, s, slen, rrtype, pkt, pktlen);
(*dlen) -= (ordlen-rdlen);
/* default comment */
w += sldns_wire2str_rr_comment_print(s, slen, rr, rrlen, dname_off,
rrtype);
w += sldns_str_print(s, slen, "\n");
return w;
}
int sldns_wire2str_rrquestion_scan(uint8_t** d, size_t* dlen, char** s,
size_t* slen, uint8_t* pkt, size_t pktlen)
{
int w = 0;
uint16_t t, c;
w += sldns_wire2str_dname_scan(d, dlen, s, slen, pkt, pktlen);
w += sldns_str_print(s, slen, "\t");
if(*dlen < 4) {
if(*dlen == 0)
return w + sldns_str_print(s, slen, "Error malformed\n");
w += print_remainder_hex("Error malformed 0x", d, dlen, s, slen);
return w + sldns_str_print(s, slen, "\n");
}
t = sldns_read_uint16(*d);
c = sldns_read_uint16((*d)+2);
(*d)+=4;
(*dlen)-=4;
w += sldns_wire2str_class_print(s, slen, c);
w += sldns_str_print(s, slen, "\t");
w += sldns_wire2str_type_print(s, slen, t);
w += sldns_str_print(s, slen, "\n");
return w;
}
int sldns_wire2str_rr_unknown_scan(uint8_t** d, size_t* dlen, char** s,
size_t* slen, uint8_t* pkt, size_t pktlen)
{
size_t rdlen, ordlen;
int w = 0;
w += sldns_wire2str_dname_scan(d, dlen, s, slen, pkt, pktlen);
w += sldns_str_print(s, slen, "\t");
w += sldns_rr_tcttl_scan(d, dlen, s, slen);
w += sldns_str_print(s, slen, "\t");
if(*dlen < 2) {
if(*dlen == 0)
return w + sldns_str_print(s, slen, ";Error missing rdatalen\n");
w += print_remainder_hex(";Error missing rdatalen 0x",
d, dlen, s, slen);
return w + sldns_str_print(s, slen, "\n");
}
rdlen = sldns_read_uint16(*d);
ordlen = rdlen;
(*d) += 2;
(*dlen) -= 2;
if(*dlen < rdlen) {
w += sldns_str_print(s, slen, "\\# %u ", (unsigned)rdlen);
if(*dlen == 0)
return w + sldns_str_print(s, slen, ";Error missing rdata\n");
w += print_remainder_hex(";Error partial rdata 0x", d, dlen, s, slen);
return w + sldns_str_print(s, slen, "\n");
}
w += sldns_wire2str_rdata_unknown_scan(d, &rdlen, s, slen);
(*dlen) -= (ordlen-rdlen);
w += sldns_str_print(s, slen, "\n");
return w;
}
/** print rr comment for type DNSKEY */
static int rr_comment_dnskey(char** s, size_t* slen, uint8_t* rr,
size_t rrlen, size_t dname_off)
{
size_t rdlen;
uint8_t* rdata;
int flags, w = 0;
if(rrlen < dname_off + 10) return 0;
rdlen = sldns_read_uint16(rr+dname_off+8);
if(rrlen < dname_off + 10 + rdlen) return 0;
rdata = rr + dname_off + 10;
flags = (int)sldns_read_uint16(rdata);
w += sldns_str_print(s, slen, " ;{");
/* id */
w += sldns_str_print(s, slen, "id = %u",
sldns_calc_keytag_raw(rdata, rdlen));
/* flags */
if((flags&LDNS_KEY_ZONE_KEY)) {
if((flags&LDNS_KEY_SEP_KEY))
w += sldns_str_print(s, slen, " (ksk)");
else w += sldns_str_print(s, slen, " (zsk)");
}
/* keysize */
if(rdlen > 4) {
w += sldns_str_print(s, slen, ", ");
w += sldns_str_print(s, slen, "size = %db",
(int)sldns_rr_dnskey_key_size_raw(
(unsigned char*)rdata+4, rdlen-4, (int)(rdata[3])));
}
w += sldns_str_print(s, slen, "}");
return w;
}
/** print rr comment for type RRSIG */
static int rr_comment_rrsig(char** s, size_t* slen, uint8_t* rr,
size_t rrlen, size_t dname_off)
{
size_t rdlen;
uint8_t* rdata;
if(rrlen < dname_off + 10) return 0;
rdlen = sldns_read_uint16(rr+dname_off+8);
if(rrlen < dname_off + 10 + rdlen) return 0;
rdata = rr + dname_off + 10;
if(rdlen < 18) return 0;
return sldns_str_print(s, slen, " ;{id = %d}",
(int)sldns_read_uint16(rdata+16));
}
/** print rr comment for type NSEC3 */
static int rr_comment_nsec3(char** s, size_t* slen, uint8_t* rr,
size_t rrlen, size_t dname_off)
{
size_t rdlen;
uint8_t* rdata;
int w = 0;
if(rrlen < dname_off + 10) return 0;
rdlen = sldns_read_uint16(rr+dname_off+8);
if(rrlen < dname_off + 10 + rdlen) return 0;
rdata = rr + dname_off + 10;
if(rdlen < 2) return 0;
if((rdata[1] & LDNS_NSEC3_VARS_OPTOUT_MASK))
w += sldns_str_print(s, slen, " ;{flags: optout}");
return w;
}
int sldns_wire2str_rr_comment_print(char** s, size_t* slen, uint8_t* rr,
size_t rrlen, size_t dname_off, uint16_t rrtype)
{
if(rrtype == LDNS_RR_TYPE_DNSKEY) {
return rr_comment_dnskey(s, slen, rr, rrlen, dname_off);
} else if(rrtype == LDNS_RR_TYPE_RRSIG) {
return rr_comment_rrsig(s, slen, rr, rrlen, dname_off);
} else if(rrtype == LDNS_RR_TYPE_NSEC3) {
return rr_comment_nsec3(s, slen, rr, rrlen, dname_off);
}
return 0;
}
int sldns_wire2str_header_scan(uint8_t** d, size_t* dlen, char** s,
size_t* slen)
{
int w = 0;
int opcode, rcode;
w += sldns_str_print(s, slen, ";; ->>HEADER<<- ");
if(*dlen == 0)
return w+sldns_str_print(s, slen, "Error empty packet");
if(*dlen < 4)
return w+print_remainder_hex("Error header too short 0x", d, dlen, s, slen);
opcode = (int)LDNS_OPCODE_WIRE(*d);
rcode = (int)LDNS_RCODE_WIRE(*d);
w += sldns_str_print(s, slen, "opcode: ");
w += sldns_wire2str_opcode_print(s, slen, opcode);
w += sldns_str_print(s, slen, ", ");
w += sldns_str_print(s, slen, "rcode: ");
w += sldns_wire2str_rcode_print(s, slen, rcode);
w += sldns_str_print(s, slen, ", ");
w += sldns_str_print(s, slen, "id: %d\n", (int)LDNS_ID_WIRE(*d));
w += sldns_str_print(s, slen, ";; flags:");
if(LDNS_QR_WIRE(*d)) w += sldns_str_print(s, slen, " qr");
if(LDNS_AA_WIRE(*d)) w += sldns_str_print(s, slen, " aa");
if(LDNS_TC_WIRE(*d)) w += sldns_str_print(s, slen, " tc");
if(LDNS_RD_WIRE(*d)) w += sldns_str_print(s, slen, " rd");
if(LDNS_CD_WIRE(*d)) w += sldns_str_print(s, slen, " cd");
if(LDNS_RA_WIRE(*d)) w += sldns_str_print(s, slen, " ra");
if(LDNS_AD_WIRE(*d)) w += sldns_str_print(s, slen, " ad");
if(LDNS_Z_WIRE(*d)) w += sldns_str_print(s, slen, " z");
w += sldns_str_print(s, slen, " ; ");
if(*dlen < LDNS_HEADER_SIZE)
return w+print_remainder_hex("Error header too short 0x", d, dlen, s, slen);
w += sldns_str_print(s, slen, "QUERY: %d, ", (int)LDNS_QDCOUNT(*d));
w += sldns_str_print(s, slen, "ANSWER: %d, ", (int)LDNS_ANCOUNT(*d));
w += sldns_str_print(s, slen, "AUTHORITY: %d, ", (int)LDNS_NSCOUNT(*d));
w += sldns_str_print(s, slen, "ADDITIONAL: %d ", (int)LDNS_ARCOUNT(*d));
*d += LDNS_HEADER_SIZE;
*dlen -= LDNS_HEADER_SIZE;
return w;
}
int sldns_wire2str_rdata_scan(uint8_t** d, size_t* dlen, char** s,
size_t* slen, uint16_t rrtype, uint8_t* pkt, size_t pktlen)
{
/* try to prettyprint, but if that fails, use unknown format */
uint8_t* origd = *d;
char* origs = *s;
size_t origdlen = *dlen, origslen = *slen;
uint16_t r_cnt, r_max;
sldns_rdf_type rdftype;
int w = 0, n;
const sldns_rr_descriptor *desc = sldns_rr_descript(rrtype);
if(!desc) /* unknown format */
return sldns_wire2str_rdata_unknown_scan(d, dlen, s, slen);
/* dlen equals the rdatalen for the rdata */
r_max = sldns_rr_descriptor_maximum(desc);
for(r_cnt=0; r_cnt < r_max; r_cnt++) {
if(*dlen == 0) {
if(r_cnt < sldns_rr_descriptor_minimum(desc))
goto failed;
break; /* nothing more to print */
}
rdftype = sldns_rr_descriptor_field_type(desc, r_cnt);
if(r_cnt != 0)
w += sldns_str_print(s, slen, " ");
n = sldns_wire2str_rdf_scan(d, dlen, s, slen, rdftype,
pkt, pktlen);
if(n == -1) {
failed:
/* failed, use unknown format */
*d = origd; *s = origs;
*dlen = origdlen; *slen = origslen;
return sldns_wire2str_rdata_unknown_scan(d, dlen,
s, slen);
}
w += n;
}
return w;
}
int sldns_wire2str_rdata_unknown_scan(uint8_t** d, size_t* dlen, char** s,
size_t* slen)
{
int w = 0;
/* print length */
w += sldns_str_print(s, slen, "\\# %u", (unsigned)*dlen);
/* print rdlen in hex */
if(*dlen != 0)
w += sldns_str_print(s, slen, " ");
w += print_hex_buf(s, slen, *d, *dlen);
(*d) += *dlen;
(*dlen) = 0;
return w;
}
/** print and escape one character for a domain dname */
static int dname_char_print(char** s, size_t* slen, uint8_t c)
{
if(c == '.' || c == ';' || c == '(' || c == ')' || c == '\\')
return sldns_str_print(s, slen, "\\%c", c);
else if(!(isascii((int)c) && isgraph((int)c)))
return sldns_str_print(s, slen, "\\%03u", (unsigned)c);
/* plain printout */
if(*slen) {
**s = (char)c;
(*s)++;
(*slen)--;
}
return 1;
}
int sldns_wire2str_dname_scan(uint8_t** d, size_t* dlen, char** s, size_t* slen,
uint8_t* pkt, size_t pktlen)
{
int w = 0;
/* spool labels onto the string, use compression if its there */
uint8_t* pos = *d;
unsigned i, counter=0;
const unsigned maxcompr = 1000; /* loop detection, max compr ptrs */
int in_buf = 1;
if(*dlen == 0) return sldns_str_print(s, slen, "ErrorMissingDname");
if(*pos == 0) {
(*d)++;
(*dlen)--;
return sldns_str_print(s, slen, ".");
}
while(*pos) {
/* read label length */
uint8_t labellen = *pos++;
if(in_buf) { (*d)++; (*dlen)--; }
/* find out what sort of label we have */
if((labellen&0xc0) == 0xc0) {
/* compressed */
uint16_t target = 0;
if(in_buf && *dlen == 0)
return w + sldns_str_print(s, slen,
"ErrorPartialDname");
else if(!in_buf && pos+1 > pkt+pktlen)
return w + sldns_str_print(s, slen,
"ErrorPartialDname");
target = ((labellen&0x3f)<<8) | *pos;
if(in_buf) { (*d)++; (*dlen)--; }
/* move to target, if possible */
if(!pkt || target >= pktlen)
return w + sldns_str_print(s, slen,
"ErrorComprPtrOutOfBounds");
if(counter++ > maxcompr)
return w + sldns_str_print(s, slen,
"ErrorComprPtrLooped");
in_buf = 0;
pos = pkt+target;
continue;
} else if((labellen&0xc0)) {
/* notimpl label type */
w += sldns_str_print(s, slen,
"ErrorLABELTYPE%xIsUnknown",
(int)(labellen&0xc0));
return w;
}
/* spool label characters, end with '.' */
if(in_buf && *dlen < labellen) labellen = *dlen;
else if(!in_buf && pos+labellen > pkt+pktlen)
labellen = (uint8_t)(pkt + pktlen - pos);
for(i=0; i<(unsigned)labellen; i++) {
w += dname_char_print(s, slen, *pos++);
}
if(in_buf) {
(*d) += labellen;
(*dlen) -= labellen;
if(*dlen == 0) break;
}
w += sldns_str_print(s, slen, ".");
}
/* skip over final root label */
if(in_buf && *dlen > 0) { (*d)++; (*dlen)--; }
/* in case we printed no labels, terminate dname */
if(w == 0) w += sldns_str_print(s, slen, ".");
return w;
}
int sldns_wire2str_opcode_print(char** s, size_t* slen, int opcode)
{
sldns_lookup_table *lt = sldns_lookup_by_id(sldns_opcodes, opcode);
if (lt && lt->name) {
return sldns_str_print(s, slen, "%s", lt->name);
}
return sldns_str_print(s, slen, "OPCODE%u", (unsigned)opcode);
}
int sldns_wire2str_rcode_print(char** s, size_t* slen, int rcode)
{
sldns_lookup_table *lt = sldns_lookup_by_id(sldns_rcodes, rcode);
if (lt && lt->name) {
return sldns_str_print(s, slen, "%s", lt->name);
}
return sldns_str_print(s, slen, "RCODE%u", (unsigned)rcode);
}
int sldns_wire2str_class_print(char** s, size_t* slen, uint16_t rrclass)
{
sldns_lookup_table *lt = sldns_lookup_by_id(sldns_rr_classes,
(int)rrclass);
if (lt && lt->name) {
return sldns_str_print(s, slen, "%s", lt->name);
}
return sldns_str_print(s, slen, "CLASS%u", (unsigned)rrclass);
}
int sldns_wire2str_type_print(char** s, size_t* slen, uint16_t rrtype)
{
const sldns_rr_descriptor *descriptor = sldns_rr_descript(rrtype);
if (descriptor && descriptor->_name) {
return sldns_str_print(s, slen, "%s", descriptor->_name);
}
return sldns_str_print(s, slen, "TYPE%u", (unsigned)rrtype);
}
int sldns_wire2str_edns_option_code_print(char** s, size_t* slen,
uint16_t opcode)
{
sldns_lookup_table *lt = sldns_lookup_by_id(sldns_edns_options,
(int)opcode);
if (lt && lt->name) {
return sldns_str_print(s, slen, "%s", lt->name);
}
return sldns_str_print(s, slen, "OPT%u", (unsigned)opcode);
}
int sldns_wire2str_class_scan(uint8_t** d, size_t* dlen, char** s, size_t* slen)
{
uint16_t c;
if(*dlen == 0) return 0;
if(*dlen < 2) return print_remainder_hex("Error malformed 0x", d, dlen, s, slen);
c = sldns_read_uint16(*d);
(*d)+=2;
(*dlen)-=2;
return sldns_wire2str_class_print(s, slen, c);
}
int sldns_wire2str_type_scan(uint8_t** d, size_t* dlen, char** s, size_t* slen)
{
uint16_t t;
if(*dlen == 0) return 0;
if(*dlen < 2) return print_remainder_hex("Error malformed 0x", d, dlen, s, slen);
t = sldns_read_uint16(*d);
(*d)+=2;
(*dlen)-=2;
return sldns_wire2str_type_print(s, slen, t);
}
int sldns_wire2str_ttl_scan(uint8_t** d, size_t* dlen, char** s, size_t* slen)
{
uint32_t ttl;
if(*dlen == 0) return 0;
if(*dlen < 4) return print_remainder_hex("Error malformed 0x", d, dlen, s, slen);
ttl = sldns_read_uint32(*d);
(*d)+=4;
(*dlen)-=4;
return sldns_str_print(s, slen, "%u", (unsigned)ttl);
}
int sldns_wire2str_rdf_scan(uint8_t** d, size_t* dlen, char** s, size_t* slen,
int rdftype, uint8_t* pkt, size_t pktlen)
{
if(*dlen == 0) return 0;
switch(rdftype) {
case LDNS_RDF_TYPE_NONE:
return 0;
case LDNS_RDF_TYPE_DNAME:
return sldns_wire2str_dname_scan(d, dlen, s, slen, pkt, pktlen);
case LDNS_RDF_TYPE_INT8:
return sldns_wire2str_int8_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_INT16:
return sldns_wire2str_int16_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_INT32:
return sldns_wire2str_int32_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_PERIOD:
return sldns_wire2str_period_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_TSIGTIME:
return sldns_wire2str_tsigtime_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_A:
return sldns_wire2str_a_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_AAAA:
return sldns_wire2str_aaaa_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_STR:
return sldns_wire2str_str_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_APL:
return sldns_wire2str_apl_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_B32_EXT:
return sldns_wire2str_b32_ext_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_B64:
return sldns_wire2str_b64_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_HEX:
return sldns_wire2str_hex_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_NSEC:
return sldns_wire2str_nsec_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_NSEC3_SALT:
return sldns_wire2str_nsec3_salt_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_TYPE:
return sldns_wire2str_type_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_CLASS:
return sldns_wire2str_class_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_CERT_ALG:
return sldns_wire2str_cert_alg_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_ALG:
return sldns_wire2str_alg_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_UNKNOWN:
return sldns_wire2str_unknown_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_TIME:
return sldns_wire2str_time_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_LOC:
return sldns_wire2str_loc_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_WKS:
case LDNS_RDF_TYPE_SERVICE:
return sldns_wire2str_wks_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_NSAP:
return sldns_wire2str_nsap_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_ATMA:
return sldns_wire2str_atma_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_IPSECKEY:
return sldns_wire2str_ipseckey_scan(d, dlen, s, slen, pkt,
pktlen);
case LDNS_RDF_TYPE_HIP:
return sldns_wire2str_hip_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_INT16_DATA:
return sldns_wire2str_int16_data_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_NSEC3_NEXT_OWNER:
return sldns_wire2str_b32_ext_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_ILNP64:
return sldns_wire2str_ilnp64_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_EUI48:
return sldns_wire2str_eui48_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_EUI64:
return sldns_wire2str_eui64_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_TAG:
return sldns_wire2str_tag_scan(d, dlen, s, slen);
case LDNS_RDF_TYPE_LONG_STR:
return sldns_wire2str_long_str_scan(d, dlen, s, slen);
}
/* unknown rdf type */
return -1;
}
int sldns_wire2str_int8_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
int w;
if(*dl < 1) return -1;
w = sldns_str_print(s, sl, "%u", (unsigned)**d);
(*d)++;
(*dl)--;
return w;
}
int sldns_wire2str_int16_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
int w;
if(*dl < 2) return -1;
w = sldns_str_print(s, sl, "%lu", (unsigned long)sldns_read_uint16(*d));
(*d)+=2;
(*dl)-=2;
return w;
}
int sldns_wire2str_int32_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
int w;
if(*dl < 4) return -1;
w = sldns_str_print(s, sl, "%lu", (unsigned long)sldns_read_uint32(*d));
(*d)+=4;
(*dl)-=4;
return w;
}
int sldns_wire2str_period_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
int w;
if(*dl < 4) return -1;
w = sldns_str_print(s, sl, "%u", (unsigned)sldns_read_uint32(*d));
(*d)+=4;
(*dl)-=4;
return w;
}
int sldns_wire2str_tsigtime_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
/* tsigtime is 48 bits network order unsigned integer */
int w;
uint64_t tsigtime = 0;
uint64_t d0, d1, d2, d3, d4, d5;
if(*dl < 6) return -1;
d0 = (*d)[0]; /* cast to uint64 for shift operations */
d1 = (*d)[1];
d2 = (*d)[2];
d3 = (*d)[3];
d4 = (*d)[4];
d5 = (*d)[5];
tsigtime = (d0<<40) | (d1<<32) | (d2<<24) | (d3<<16) | (d4<<8) | d5;
#ifndef USE_WINSOCK
w = sldns_str_print(s, sl, "%llu", (long long)tsigtime);
#else
w = sldns_str_print(s, sl, "%I64u", (long long)tsigtime);
#endif
(*d)+=6;
(*dl)-=6;
return w;
}
int sldns_wire2str_a_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
char buf[32];
int w;
if(*dl < 4) return -1;
if(!inet_ntop(AF_INET, *d, buf, (socklen_t)sizeof(buf)))
return -1;
w = sldns_str_print(s, sl, "%s", buf);
(*d)+=4;
(*dl)-=4;
return w;
}
int sldns_wire2str_aaaa_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
#ifdef AF_INET6
char buf[64];
int w;
if(*dl < 16) return -1;
if(!inet_ntop(AF_INET6, *d, buf, (socklen_t)sizeof(buf)))
return -1;
w = sldns_str_print(s, sl, "%s", buf);
(*d)+=16;
(*dl)-=16;
return w;
#else
return -1;
#endif
}
/** printout escaped TYPE_STR character */
static int str_char_print(char** s, size_t* sl, uint8_t c)
{
if(isprint((int)c) || c == '\t') {
if(c == '\"' || c == '\\')
return sldns_str_print(s, sl, "\\%c", c);
if(*sl) {
**s = (char)c;
(*s)++;
(*sl)--;
}
return 1;
}
return sldns_str_print(s, sl, "\\%03u", (unsigned)c);
}
int sldns_wire2str_str_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
int w = 0;
size_t i, len;
if(*dl < 1) return -1;
len = **d;
if(*dl < 1+len) return -1;
(*d)++;
(*dl)--;
w += sldns_str_print(s, sl, "\"");
for(i=0; i<len; i++)
w += str_char_print(s, sl, (*d)[i]);
w += sldns_str_print(s, sl, "\"");
(*d)+=len;
(*dl)-=len;
return w;
}
int sldns_wire2str_apl_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
int i, w = 0;
uint16_t family;
uint8_t negation, prefix, adflength;
if(*dl < 4) return -1;
family = sldns_read_uint16(*d);
prefix = (*d)[2];
negation = ((*d)[3] & LDNS_APL_NEGATION);
adflength = ((*d)[3] & LDNS_APL_MASK);
if(*dl < 4+(size_t)adflength) return -1;
if(family != LDNS_APL_IP4 && family != LDNS_APL_IP6)
return -1; /* unknown address family */
if(negation)
w += sldns_str_print(s, sl, "!");
w += sldns_str_print(s, sl, "%u:", (unsigned)family);
if(family == LDNS_APL_IP4) {
/* check if prefix <32 ? */
/* address is variable length 0 - 4 */
for(i=0; i<4; i++) {
if(i > 0)
w += sldns_str_print(s, sl, ".");
if(i < (int)adflength)
w += sldns_str_print(s, sl, "%d", (*d)[4+i]);
else w += sldns_str_print(s, sl, "0");
}
} else if(family == LDNS_APL_IP6) {
/* check if prefix <128 ? */
/* address is variable length 0 - 16 */
for(i=0; i<16; i++) {
if(i%2 == 0 && i>0)
w += sldns_str_print(s, sl, ":");
if(i < (int)adflength)
w += sldns_str_print(s, sl, "%02x", (*d)[4+i]);
else w += sldns_str_print(s, sl, "00");
}
}
w += sldns_str_print(s, sl, "/%u", (unsigned)prefix);
(*d) += 4+adflength;
(*dl) -= 4+adflength;
return w;
}
int sldns_wire2str_b32_ext_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
size_t datalen;
size_t sz;
if(*dl < 1) return -1;
datalen = (*d)[0];
if(*dl < 1+datalen) return -1;
sz = sldns_b32_ntop_calculate_size(datalen);
if(*sl < sz+1) {
(*d) += datalen+1;
(*dl) -= (datalen+1);
return (int)sz; /* out of space really, but would need buffer
in order to truncate the output */
}
sldns_b32_ntop_extended_hex((*d)+1, datalen, *s, *sl);
(*d) += datalen+1;
(*dl) -= (datalen+1);
(*s) += sz;
(*sl) -= sz;
return (int)sz;
}
/** scan number of bytes from wire into b64 presentation format */
static int sldns_wire2str_b64_scan_num(uint8_t** d, size_t* dl, char** s,
size_t* sl, size_t num)
{
/* b64_ntop_calculate size includes null at the end */
size_t sz = sldns_b64_ntop_calculate_size(num)-1;
if(*sl < sz+1) {
(*d) += num;
(*dl) -= num;
return (int)sz; /* out of space really, but would need buffer
in order to truncate the output */
}
sldns_b64_ntop(*d, num, *s, *sl);
(*d) += num;
(*dl) -= num;
(*s) += sz;
(*sl) -= sz;
return (int)sz;
}
int sldns_wire2str_b64_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
return sldns_wire2str_b64_scan_num(d, dl, s, sl, *dl);
}
int sldns_wire2str_hex_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
return print_remainder_hex("", d, dl, s, sl);
}
int sldns_wire2str_nsec_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
uint8_t* p = *d;
size_t pl = *dl;
unsigned i, bit, window, block_len;
uint16_t t;
int w = 0;
/* check for errors */
while(pl) {
if(pl < 2) return -1;
block_len = (unsigned)p[1];
if(pl < 2+block_len) return -1;
p += block_len+2;
pl -= block_len+2;
}
/* do it */
p = *d;
pl = *dl;
while(pl) {
if(pl < 2) return -1; /* cannot happen */
window = (unsigned)p[0];
block_len = (unsigned)p[1];
if(pl < 2+block_len) return -1; /* cannot happen */
p += 2;
for(i=0; i<block_len; i++) {
if(p[i] == 0) continue;
/* base type number for this octet */
t = ((window)<<8) | (i << 3);
for(bit=0; bit<8; bit++) {
if((p[i]&(0x80>>bit))) {
if(w) w += sldns_str_print(s, sl, " ");
w += sldns_wire2str_type_print(s, sl,
t+bit);
}
}
}
p += block_len;
pl -= block_len+2;
}
(*d) += *dl;
(*dl) = 0;
return w;
}
int sldns_wire2str_nsec3_salt_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
size_t salt_len;
int w;
if(*dl < 1) return -1;
salt_len = (size_t)(*d)[0];
if(*dl < 1+salt_len) return -1;
(*d)++;
(*dl)--;
if(salt_len == 0) {
return sldns_str_print(s, sl, "-");
}
w = print_hex_buf(s, sl, *d, salt_len);
(*dl)-=salt_len;
(*d)+=salt_len;
return w;
}
int sldns_wire2str_cert_alg_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
sldns_lookup_table *lt;
int data, w;
if(*dl < 2) return -1;
data = (int)sldns_read_uint16(*d);
lt = sldns_lookup_by_id(sldns_cert_algorithms, data);
if(lt && lt->name)
w = sldns_str_print(s, sl, "%s", lt->name);
else w = sldns_str_print(s, sl, "%d", data);
(*dl)-=2;
(*d)+=2;
return w;
}
int sldns_wire2str_alg_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
/* don't use algorithm mnemonics in the presentation format
* this kind of got sneaked into the rfc's */
return sldns_wire2str_int8_scan(d, dl, s, sl);
}
int sldns_wire2str_unknown_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
return sldns_wire2str_rdata_unknown_scan(d, dl, s, sl);
}
int sldns_wire2str_time_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
/* create a YYYYMMDDHHMMSS string if possible */
struct tm tm;
char date_buf[16];
uint32_t t;
memset(&tm, 0, sizeof(tm));
if(*dl < 4) return -1;
t = sldns_read_uint32(*d);
date_buf[15]=0;
if(sldns_serial_arithmitics_gmtime_r(t, time(NULL), &tm) &&
strftime(date_buf, 15, "%Y%m%d%H%M%S", &tm)) {
(*d) += 4;
(*dl) -= 4;
return sldns_str_print(s, sl, "%s", date_buf);
}
return -1;
}
static int
loc_cm_print(char** str, size_t* sl, uint8_t mantissa, uint8_t exponent)
{
int w = 0;
uint8_t i;
/* is it 0.<two digits> ? */
if(exponent < 2) {
if(exponent == 1)
mantissa *= 10;
return sldns_str_print(str, sl, "0.%02ld", (long)mantissa);
}
/* always <digit><string of zeros> */
w += sldns_str_print(str, sl, "%d", (int)mantissa);
for(i=0; i<exponent-2; i++)
w += sldns_str_print(str, sl, "0");
return w;
}
int sldns_wire2str_loc_scan(uint8_t** d, size_t* dl, char** str, size_t* sl)
{
/* we could do checking (ie degrees < 90 etc)? */
uint8_t version;
uint8_t size;
uint8_t horizontal_precision;
uint8_t vertical_precision;
uint32_t longitude;
uint32_t latitude;
uint32_t altitude;
char northerness;
char easterness;
uint32_t h;
uint32_t m;
double s;
uint32_t equator = (uint32_t)1 << 31; /* 2**31 */
int w = 0;
if(*dl < 16) return -1;
version = (*d)[0];
if(version != 0)
return sldns_wire2str_hex_scan(d, dl, str, sl);
size = (*d)[1];
horizontal_precision = (*d)[2];
vertical_precision = (*d)[3];
latitude = sldns_read_uint32((*d)+4);
longitude = sldns_read_uint32((*d)+8);
altitude = sldns_read_uint32((*d)+12);
if (latitude > equator) {
northerness = 'N';
latitude = latitude - equator;
} else {
northerness = 'S';
latitude = equator - latitude;
}
h = latitude / (1000 * 60 * 60);
latitude = latitude % (1000 * 60 * 60);
m = latitude / (1000 * 60);
latitude = latitude % (1000 * 60);
s = (double) latitude / 1000.0;
w += sldns_str_print(str, sl, "%02u %02u %06.3f %c ",
h, m, s, northerness);
if (longitude > equator) {
easterness = 'E';
longitude = longitude - equator;
} else {
easterness = 'W';
longitude = equator - longitude;
}
h = longitude / (1000 * 60 * 60);
longitude = longitude % (1000 * 60 * 60);
m = longitude / (1000 * 60);
longitude = longitude % (1000 * 60);
s = (double) longitude / (1000.0);
w += sldns_str_print(str, sl, "%02u %02u %06.3f %c ",
h, m, s, easterness);
s = ((double) altitude) / 100;
s -= 100000;
if(altitude%100 != 0)
w += sldns_str_print(str, sl, "%.2f", s);
else
w += sldns_str_print(str, sl, "%.0f", s);
w += sldns_str_print(str, sl, "m ");
w += loc_cm_print(str, sl, (size & 0xf0) >> 4, size & 0x0f);
w += sldns_str_print(str, sl, "m ");
w += loc_cm_print(str, sl, (horizontal_precision & 0xf0) >> 4,
horizontal_precision & 0x0f);
w += sldns_str_print(str, sl, "m ");
w += loc_cm_print(str, sl, (vertical_precision & 0xf0) >> 4,
vertical_precision & 0x0f);
w += sldns_str_print(str, sl, "m");
(*d)+=16;
(*dl)-=16;
return w;
}
int sldns_wire2str_wks_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
/* protocol, followed by bitmap of services */
const char* proto_name = NULL;
struct protoent *protocol;
struct servent *service;
uint8_t protocol_nr;
int bit, port, w = 0;
size_t i;
/* we cannot print with strings because they
* are not portable, the presentation format may
* not be able to be read in on another computer. */
int print_symbols = 0;
/* protocol */
if(*dl < 1) return -1;
protocol_nr = (*d)[0];
(*d)++;
(*dl)--;
protocol = getprotobynumber((int)protocol_nr);
if(protocol && (protocol->p_name != NULL)) {
w += sldns_str_print(s, sl, "%s", protocol->p_name);
proto_name = protocol->p_name;
} else {
w += sldns_str_print(s, sl, "%u", (unsigned)protocol_nr);
}
for(i=0; i<*dl; i++) {
if((*d)[i] == 0)
continue;
for(bit=0; bit<8; bit++) {
if(!(((*d)[i])&(0x80>>bit)))
continue;
port = (int)i*8 + bit;
if(!print_symbols)
service = NULL;
else
service = getservbyport(
(int)htons((uint16_t)port), proto_name);
if(service && service->s_name)
w += sldns_str_print(s, sl, " %s",
service->s_name);
else w += sldns_str_print(s, sl, " %u",
(unsigned)port);
}
}
#ifdef HAVE_ENDSERVENT
endservent();
#endif
#ifdef HAVE_ENDPROTOENT
endprotoent();
#endif
(*d) += *dl;
(*dl) = 0;
return w;
}
int sldns_wire2str_nsap_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
return print_remainder_hex("0x", d, dl, s, sl);
}
int sldns_wire2str_atma_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
return print_remainder_hex("", d, dl, s, sl);
}
/* internal scan routine that can modify arguments on failure */
static int sldns_wire2str_ipseckey_scan_internal(uint8_t** d, size_t* dl,
char** s, size_t* sl, uint8_t* pkt, size_t pktlen)
{
/* http://www.ietf.org/internet-drafts/draft-ietf-ipseckey-rr-12.txt*/
uint8_t precedence, gateway_type, algorithm;
int w = 0;
if(*dl < 3) return -1;
precedence = (*d)[0];
gateway_type = (*d)[1];
algorithm = (*d)[2];
if(gateway_type > 3)
return -1; /* unknown */
(*d)+=3;
(*dl)-=3;
w += sldns_str_print(s, sl, "%d %d %d ",
(int)precedence, (int)gateway_type, (int)algorithm);
switch(gateway_type) {
case 0: /* no gateway */
w += sldns_str_print(s, sl, ".");
break;
case 1: /* ip4 */
w += sldns_wire2str_a_scan(d, dl, s, sl);
break;
case 2: /* ip6 */
w += sldns_wire2str_aaaa_scan(d, dl, s, sl);
break;
case 3: /* dname */
w += sldns_wire2str_dname_scan(d, dl, s, sl, pkt, pktlen);
break;
default: /* unknown */
return -1;
}
if(*dl < 1)
return -1;
w += sldns_str_print(s, sl, " ");
w += sldns_wire2str_b64_scan_num(d, dl, s, sl, *dl);
return w;
}
int sldns_wire2str_ipseckey_scan(uint8_t** d, size_t* dl, char** s, size_t* sl,
uint8_t* pkt, size_t pktlen)
{
uint8_t* od = *d;
char* os = *s;
size_t odl = *dl, osl = *sl;
int w=sldns_wire2str_ipseckey_scan_internal(d, dl, s, sl, pkt, pktlen);
if(w == -1) {
*d = od;
*s = os;
*dl = odl;
*sl = osl;
return -1;
}
return w;
}
int sldns_wire2str_hip_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
int w;
uint8_t algo, hitlen;
uint16_t pklen;
/* read lengths */
if(*dl < 4)
return -1;
hitlen = (*d)[0];
algo = (*d)[1];
pklen = sldns_read_uint16((*d)+2);
if(*dl < (size_t)4 + (size_t)hitlen + (size_t)pklen)
return -1;
/* write: algo hit pubkey */
w = sldns_str_print(s, sl, "%u ", (unsigned)algo);
w += print_hex_buf(s, sl, (*d)+4, hitlen);
w += sldns_str_print(s, sl, " ");
(*d)+=4+hitlen;
(*dl)-= (4+hitlen);
w += sldns_wire2str_b64_scan_num(d, dl, s, sl, pklen);
return w;
}
int sldns_wire2str_int16_data_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
uint16_t n;
if(*dl < 2)
return -1;
n = sldns_read_uint16(*d);
if(*dl < 2+(size_t)n)
return -1;
(*d)+=2;
(*dl)-=2;
return sldns_wire2str_b64_scan_num(d, dl, s, sl, n);
}
int sldns_wire2str_nsec3_next_owner_scan(uint8_t** d, size_t* dl, char** s,
size_t* sl)
{
return sldns_wire2str_b32_ext_scan(d, dl, s, sl);
}
int sldns_wire2str_ilnp64_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
int w;
if(*dl < 8)
return -1;
w = sldns_str_print(s, sl, "%.4x:%.4x:%.4x:%.4x",
sldns_read_uint16(*d), sldns_read_uint16((*d)+2),
sldns_read_uint16((*d)+4), sldns_read_uint16((*d)+6));
(*d)+=8;
(*dl)-=8;
return w;
}
int sldns_wire2str_eui48_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
int w;
if(*dl < 6)
return -1;
w = sldns_str_print(s, sl, "%.2x-%.2x-%.2x-%.2x-%.2x-%.2x",
(*d)[0], (*d)[1], (*d)[2], (*d)[3], (*d)[4], (*d)[5]);
(*d)+=6;
(*dl)-=6;
return w;
}
int sldns_wire2str_eui64_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
int w;
if(*dl < 8)
return -1;
w = sldns_str_print(s, sl, "%.2x-%.2x-%.2x-%.2x-%.2x-%.2x-%.2x-%.2x",
(*d)[0], (*d)[1], (*d)[2], (*d)[3], (*d)[4], (*d)[5],
(*d)[6], (*d)[7]);
(*d)+=8;
(*dl)-=8;
return w;
}
int sldns_wire2str_tag_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
size_t i, n;
int w = 0;
if(*dl < 1)
return -1;
n = (size_t)((*d)[0]);
if(*dl < 1+n)
return -1;
for(i=0; i<n; i++)
if(!isalnum((int)(*d)[i]))
return -1;
for(i=0; i<n; i++)
w += sldns_str_print(s, sl, "%c", (char)(*d)[i]);
(*d)+=n+1;
(*dl)-=(n+1);
return w;
}
int sldns_wire2str_long_str_scan(uint8_t** d, size_t* dl, char** s, size_t* sl)
{
size_t i;
int w = 0;
w += sldns_str_print(s, sl, "\"");
for(i=0; i<*dl; i++)
w += str_char_print(s, sl, (*d)[i]);
w += sldns_str_print(s, sl, "\"");
(*d)+=*dl;
(*dl)=0;
return w;
}
int sldns_wire2str_edns_llq_print(char** s, size_t* sl, uint8_t* data,
size_t len)
{
/* LLQ constants */
const char* llq_errors[] = {"NO-ERROR", "SERV-FULL", "STATIC",
"FORMAT-ERR", "NO-SUCH-LLQ", "BAD-VERS", "UNKNOWN_ERR"};
const unsigned int llq_errors_num = 7;
const char* llq_opcodes[] = {"LLQ-SETUP", "LLQ-REFRESH", "LLQ-EVENT"};
const unsigned int llq_opcodes_num = 3;
uint16_t version, llq_opcode, error_code;
uint64_t llq_id;
uint32_t lease_life; /* Requested or granted life of LLQ, in seconds */
int w = 0;
/* read the record */
if(len != 18) {
w += sldns_str_print(s, sl, "malformed LLQ ");
w += print_hex_buf(s, sl, data, len);
return w;
}
version = sldns_read_uint16(data);
llq_opcode = sldns_read_uint16(data+2);
error_code = sldns_read_uint16(data+4);
memmove(&llq_id, data+6, sizeof(llq_id));
lease_life = sldns_read_uint32(data+14);
/* print it */
w += sldns_str_print(s, sl, "v%d ", (int)version);
if(llq_opcode < llq_opcodes_num)
w += sldns_str_print(s, sl, "%s", llq_opcodes[llq_opcode]);
else w += sldns_str_print(s, sl, "opcode %d", (int)llq_opcode);
if(error_code < llq_errors_num)
w += sldns_str_print(s, sl, " %s", llq_errors[error_code]);
else w += sldns_str_print(s, sl, " error %d", (int)error_code);
#ifndef USE_WINSOCK
w += sldns_str_print(s, sl, " id %llx lease-life %lu",
(unsigned long long)llq_id, (unsigned long)lease_life);
#else
w += sldns_str_print(s, sl, " id %I64x lease-life %lu",
(unsigned long long)llq_id, (unsigned long)lease_life);
#endif
return w;
}
int sldns_wire2str_edns_ul_print(char** s, size_t* sl, uint8_t* data,
size_t len)
{
uint32_t lease;
int w = 0;
if(len != 4) {
w += sldns_str_print(s, sl, "malformed UL ");
w += print_hex_buf(s, sl, data, len);
return w;
}
lease = sldns_read_uint32(data);
w += sldns_str_print(s, sl, "lease %lu", (unsigned long)lease);
return w;
}
int sldns_wire2str_edns_nsid_print(char** s, size_t* sl, uint8_t* data,
size_t len)
{
int w = 0;
size_t i, printed=0;
w += print_hex_buf(s, sl, data, len);
for(i=0; i<len; i++) {
if(isprint((int)data[i]) || data[i] == '\t') {
if(!printed) {
w += sldns_str_print(s, sl, " (");
printed = 1;
}
w += sldns_str_print(s, sl, "%c", (char)data[i]);
}
}
if(printed)
w += sldns_str_print(s, sl, ")");
return w;
}
int sldns_wire2str_edns_dau_print(char** s, size_t* sl, uint8_t* data,
size_t len)
{
sldns_lookup_table *lt;
size_t i;
int w = 0;
for(i=0; i<len; i++) {
lt = sldns_lookup_by_id(sldns_algorithms, (int)data[i]);
if(lt && lt->name)
w += sldns_str_print(s, sl, " %s", lt->name);
else w += sldns_str_print(s, sl, " %d", (int)data[i]);
}
return w;
}
int sldns_wire2str_edns_dhu_print(char** s, size_t* sl, uint8_t* data,
size_t len)
{
sldns_lookup_table *lt;
size_t i;
int w = 0;
for(i=0; i<len; i++) {
lt = sldns_lookup_by_id(sldns_hashes, (int)data[i]);
if(lt && lt->name)
w += sldns_str_print(s, sl, " %s", lt->name);
else w += sldns_str_print(s, sl, " %d", (int)data[i]);
}
return w;
}
int sldns_wire2str_edns_n3u_print(char** s, size_t* sl, uint8_t* data,
size_t len)
{
size_t i;
int w = 0;
for(i=0; i<len; i++) {
if(data[i] == 1)
w += sldns_str_print(s, sl, " SHA1");
else w += sldns_str_print(s, sl, " %d", (int)data[i]);
}
return w;
}
int sldns_wire2str_edns_subnet_print(char** s, size_t* sl, uint8_t* data,
size_t len)
{
int w = 0;
uint16_t family;
uint8_t source, scope;
if(len < 4) {
w += sldns_str_print(s, sl, "malformed subnet ");
w += print_hex_buf(s, sl, data, len);
return w;
}
family = sldns_read_uint16(data);
source = data[2];
scope = data[3];
if(family == 1) {
/* IP4 */
char buf[64];
uint8_t ip4[4];
memset(ip4, 0, sizeof(ip4));
if(len-4 > 4) {
w += sldns_str_print(s, sl, "trailingdata:");
w += print_hex_buf(s, sl, data+4+4, len-4-4);
w += sldns_str_print(s, sl, " ");
len = 4+4;
}
memmove(ip4, data+4, len-4);
if(!inet_ntop(AF_INET, ip4, buf, (socklen_t)sizeof(buf))) {
w += sldns_str_print(s, sl, "ip4ntoperror ");
w += print_hex_buf(s, sl, data+4+4, len-4-4);
} else {
w += sldns_str_print(s, sl, "%s", buf);
}
} else if(family == 2) {
/* IP6 */
char buf[64];
uint8_t ip6[16];
memset(ip6, 0, sizeof(ip6));
if(len-4 > 16) {
w += sldns_str_print(s, sl, "trailingdata:");
w += print_hex_buf(s, sl, data+4+16, len-4-16);
w += sldns_str_print(s, sl, " ");
len = 4+16;
}
memmove(ip6, data+4, len-4);
#ifdef AF_INET6
if(!inet_ntop(AF_INET6, ip6, buf, (socklen_t)sizeof(buf))) {
w += sldns_str_print(s, sl, "ip6ntoperror ");
w += print_hex_buf(s, sl, data+4+4, len-4-4);
} else {
w += sldns_str_print(s, sl, "%s", buf);
}
#else
w += print_hex_buf(s, sl, data+4+4, len-4-4);
#endif
} else {
/* unknown */
w += sldns_str_print(s, sl, "family %d ",
(int)family);
w += print_hex_buf(s, sl, data, len);
}
w += sldns_str_print(s, sl, "/%d scope /%d", (int)source, (int)scope);
return w;
}
int sldns_wire2str_edns_option_print(char** s, size_t* sl,
uint16_t option_code, uint8_t* optdata, size_t optlen)
{
int w = 0;
w += sldns_wire2str_edns_option_code_print(s, sl, option_code);
w += sldns_str_print(s, sl, ": ");
switch(option_code) {
case LDNS_EDNS_LLQ:
w += sldns_wire2str_edns_llq_print(s, sl, optdata, optlen);
break;
case LDNS_EDNS_UL:
w += sldns_wire2str_edns_ul_print(s, sl, optdata, optlen);
break;
case LDNS_EDNS_NSID:
w += sldns_wire2str_edns_nsid_print(s, sl, optdata, optlen);
break;
case LDNS_EDNS_DAU:
w += sldns_wire2str_edns_dau_print(s, sl, optdata, optlen);
break;
case LDNS_EDNS_DHU:
w += sldns_wire2str_edns_dhu_print(s, sl, optdata, optlen);
break;
case LDNS_EDNS_N3U:
w += sldns_wire2str_edns_n3u_print(s, sl, optdata, optlen);
break;
case LDNS_EDNS_CLIENT_SUBNET:
w += sldns_wire2str_edns_subnet_print(s, sl, optdata, optlen);
break;
default:
/* unknown option code */
w += print_hex_buf(s, sl, optdata, optlen);
break;
}
return w;
}
/** print the edns options to string */
static int
print_edns_opts(char** s, size_t* sl, uint8_t* rdata, size_t rdatalen)
{
uint16_t option_code, option_len;
int w = 0;
while(rdatalen > 0) {
/* option name */
if(rdatalen < 4) {
w += sldns_str_print(s, sl, " ; malformed: ");
w += print_hex_buf(s, sl, rdata, rdatalen);
return w;
}
option_code = sldns_read_uint16(rdata);
option_len = sldns_read_uint16(rdata+2);
rdata += 4;
rdatalen -= 4;
/* option value */
if(rdatalen < (size_t)option_len) {
w += sldns_str_print(s, sl, " ; malformed ");
w += sldns_wire2str_edns_option_code_print(s, sl,
option_code);
w += sldns_str_print(s, sl, ": ");
w += print_hex_buf(s, sl, rdata, rdatalen);
return w;
}
w += sldns_str_print(s, sl, " ; ");
w += sldns_wire2str_edns_option_print(s, sl, option_code,
rdata, option_len);
rdata += option_len;
rdatalen -= option_len;
}
return w;
}
int sldns_wire2str_edns_scan(uint8_t** data, size_t* data_len, char** str,
size_t* str_len, uint8_t* pkt, size_t pktlen)
{
int w = 0;
uint8_t ext_rcode, edns_version;
uint16_t udpsize, edns_bits, rdatalen;
w += sldns_str_print(str, str_len, "; EDNS:");
/* some input checks, domain name */
if(*data_len < 1+10)
return w + print_remainder_hex("Error malformed 0x",
data, data_len, str, str_len);
if(*data[0] != 0) {
return w + print_remainder_hex("Error nonrootdname 0x",
data, data_len, str, str_len);
}
(*data)++;
(*data_len)--;
/* check type and read fixed contents */
if(sldns_read_uint16((*data)) != LDNS_RR_TYPE_OPT) {
return w + print_remainder_hex("Error nottypeOPT 0x",
data, data_len, str, str_len);
}
udpsize = sldns_read_uint16((*data)+2);
ext_rcode = (*data)[4];
edns_version = (*data)[5];
edns_bits = sldns_read_uint16((*data)+6);
rdatalen = sldns_read_uint16((*data)+8);
(*data)+=10;
(*data_len)-=10;
w += sldns_str_print(str, str_len, " version: %u;",
(unsigned)edns_version);
w += sldns_str_print(str, str_len, " flags:");
if((edns_bits & LDNS_EDNS_MASK_DO_BIT))
w += sldns_str_print(str, str_len, " do");
/* the extended rcode is the value set, shifted four bits,
* and or'd with the original rcode */
if(ext_rcode) {
int rc = ((int)ext_rcode)<<4;
if(pkt && pktlen >= LDNS_HEADER_SIZE)
rc |= LDNS_RCODE_WIRE(pkt);
w += sldns_str_print(str, str_len, " ; ext-rcode: %d", rc);
}
w += sldns_str_print(str, str_len, " ; udp: %u", (unsigned)udpsize);
if(rdatalen) {
if(*data_len < rdatalen) {
w += sldns_str_print(str, str_len,
" ; Error EDNS rdata too short; ");
rdatalen = *data_len;
}
w += print_edns_opts(str, str_len, *data, rdatalen);
(*data) += rdatalen;
(*data_len) -= rdatalen;
}
w += sldns_str_print(str, str_len, "\n");
return w;
}
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