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Diffstat (limited to '')
| -rw-r--r-- | external/unbound/testcode/pktview.c | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/external/unbound/testcode/pktview.c b/external/unbound/testcode/pktview.c new file mode 100644 index 000000000..e59283fa8 --- /dev/null +++ b/external/unbound/testcode/pktview.c @@ -0,0 +1,202 @@ +/* + * testcode/pktview.c - debug program to disassemble a DNS packet. + * + * Copyright (c) 2007, NLnet Labs. All rights reserved. + * + * This software is open source. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * + * 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. + * + * Neither the name of the NLNET LABS 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 COPYRIGHT HOLDERS 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 COPYRIGHT + * HOLDER 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. + */ + +/** + * \file + * + * This program shows a dns packet wire format. + */ + +#include "config.h" +#include "util/log.h" +#include "util/data/dname.h" +#include "util/data/msgparse.h" +#include "testcode/unitmain.h" +#include "testcode/readhex.h" +#include "ldns/sbuffer.h" +#include "ldns/parseutil.h" + +/** usage information for pktview */ +static void usage(char* argv[]) +{ + printf("usage: %s\n", argv[0]); + printf("present hex packet on stdin.\n"); + exit(1); +} + +/** read hex input */ +static void read_input(sldns_buffer* pkt, FILE* in) +{ + char buf[102400]; + char* np = buf; + while(fgets(np, (int)sizeof(buf) - (np-buf), in)) { + if(buf[0] == ';') /* comment */ + continue; + np = &np[strlen(np)]; + } + hex_to_buf(pkt, buf); +} + +/** analyze domain name in packet, possibly compressed */ +static void analyze_dname(sldns_buffer* pkt) +{ + size_t oldpos = sldns_buffer_position(pkt); + size_t len; + printf("[pos %d] dname: ", (int)oldpos); + dname_print(stdout, pkt, sldns_buffer_current(pkt)); + len = pkt_dname_len(pkt); + printf(" len=%d", (int)len); + if(sldns_buffer_position(pkt)-oldpos != len) + printf(" comprlen=%d\n", + (int)(sldns_buffer_position(pkt)-oldpos)); + else printf("\n"); +} + +/** analyze rdata in packet */ +static void analyze_rdata(sldns_buffer*pkt, const sldns_rr_descriptor* desc, + uint16_t rdlen) +{ + int rdf = 0; + int count = (int)desc->_dname_count; + size_t len, oldpos; + while(rdlen > 0 && count) { + switch(desc->_wireformat[rdf]) { + case LDNS_RDF_TYPE_DNAME: + oldpos = sldns_buffer_position(pkt); + analyze_dname(pkt); + rdlen -= sldns_buffer_position(pkt)-oldpos; + count --; + len = 0; + break; + case LDNS_RDF_TYPE_STR: + len = sldns_buffer_current(pkt)[0] + 1; + break; + default: + len = get_rdf_size(desc->_wireformat[rdf]); + } + if(len) { + printf(" wf[%d]", (int)len); + sldns_buffer_skip(pkt, (ssize_t)len); + rdlen -= len; + } + rdf++; + } + if(rdlen) { + size_t i; + printf(" remain[%d]\n", (int)rdlen); + for(i=0; i<rdlen; i++) + printf(" %2.2X", (unsigned)sldns_buffer_current(pkt)[i]); + printf("\n"); + } + else printf("\n"); + sldns_buffer_skip(pkt, (ssize_t)rdlen); +} + +/** analyze rr in packet */ +static void analyze_rr(sldns_buffer* pkt, int q) +{ + uint16_t type, dclass, len; + uint32_t ttl; + analyze_dname(pkt); + type = sldns_buffer_read_u16(pkt); + dclass = sldns_buffer_read_u16(pkt); + printf("type %s(%d)", sldns_rr_descript(type)? + sldns_rr_descript(type)->_name: "??" , (int)type); + printf(" class %s(%d) ", sldns_lookup_by_id(sldns_rr_classes, + (int)dclass)?sldns_lookup_by_id(sldns_rr_classes, + (int)dclass)->name:"??", (int)dclass); + if(q) { + printf("\n"); + } else { + ttl = sldns_buffer_read_u32(pkt); + printf(" ttl %d (0x%x)", (int)ttl, (unsigned)ttl); + len = sldns_buffer_read_u16(pkt); + printf(" rdata len %d:\n", (int)len); + if(sldns_rr_descript(type)) + analyze_rdata(pkt, sldns_rr_descript(type), len); + else sldns_buffer_skip(pkt, (ssize_t)len); + } +} + +/** analyse pkt */ +static void analyze(sldns_buffer* pkt) +{ + uint16_t i, f, qd, an, ns, ar; + int rrnum = 0; + printf("packet length %d\n", (int)sldns_buffer_limit(pkt)); + if(sldns_buffer_limit(pkt) < 12) return; + + i = sldns_buffer_read_u16(pkt); + printf("id (hostorder): %d (0x%x)\n", (int)i, (unsigned)i); + f = sldns_buffer_read_u16(pkt); + printf("flags: 0x%x\n", (unsigned)f); + qd = sldns_buffer_read_u16(pkt); + printf("qdcount: %d\n", (int)qd); + an = sldns_buffer_read_u16(pkt); + printf("ancount: %d\n", (int)an); + ns = sldns_buffer_read_u16(pkt); + printf("nscount: %d\n", (int)ns); + ar = sldns_buffer_read_u16(pkt); + printf("arcount: %d\n", (int)ar); + + printf(";-- query section\n"); + while(sldns_buffer_remaining(pkt) > 0) { + if(rrnum == (int)qd) + printf(";-- answer section\n"); + if(rrnum == (int)qd+(int)an) + printf(";-- authority section\n"); + if(rrnum == (int)qd+(int)an+(int)ns) + printf(";-- additional section\n"); + printf("rr %d ", rrnum); + analyze_rr(pkt, rrnum < (int)qd); + rrnum++; + } +} + +/** main program for pktview */ +int main(int argc, char* argv[]) +{ + sldns_buffer* pkt = sldns_buffer_new(65553); + if(argc != 1) { + usage(argv); + } + if(!pkt) fatal_exit("out of memory"); + + read_input(pkt, stdin); + analyze(pkt); + + sldns_buffer_free(pkt); + return 0; +} |