3rd-party/libtins
1
0
Fork 0
mirror of https://github.com/mfontanini/libtins synced 2026-01-23 02:35:57 +01:00
Code Issues Releases Wiki Activity

Fixed some issues when parsing DNS answers. MX records are now serialized correctly.

Browse Source
This commit is contained in:
Matias Fontanini
2013-08-04 14:27:03 -03:00
parent 2cc0ceb1aa
commit 4ca21bdad7
2 changed files with 34 additions and 15 deletions
Download Patch File Download Diff File Expand all files Collapse all files

45
src/dns.cpp
View File

@@ -224,9 +224,17 @@ DNSResourceRecord DNS::make_record(const std::string &name,
const DNSResourceRecord::info &info, const uint8_t *ptr, uint32_t len)
{
string nm;
std::basic_string<uint8_t> data;
parse_domain_name(name, nm);
uint16_t index = find_domain_name(nm);
DNSResourceRecord res;
if(info.type == MX) {
data.push_back(0);
data.push_back(0);
data.insert(data.end(), ptr, ptr + len);
ptr = &data[0];
len = data.size();
}
if(index)
res = make_offseted_record(Endian::host_to_be(index), ptr, len);
else
@@ -437,25 +445,36 @@ void DNS::convert_resources(const ResourcesType &lst, std::list<Resource> &res)
}
ptr = it->data_ptr();
sz = it->data_size();
if(sz == 4)
addr = IPv4Address(*(uint32_t*)ptr).to_string();
else {
if(Endian::be_to_host(it->information().type) == MX) {
ptr += 2;
sz -= 2;
}
if(Endian::be_to_host(it->information().type) == DNS::AAAA) {
uint16_t record_type = Endian::be_to_host(it->information().type);
// Skip the preference field if it's MX
if(record_type == MX) {
ptr += 2;
sz -= 2;
}
switch(record_type) {
case AAAA:
if(sz != 16)
throw std::runtime_error("Malformed IPv6 address");
throw malformed_packet();
addr = IPv6Address(ptr).to_string();
}
else if(Endian::be_to_host(it->information().type) <= NSEC3PARAM)
break;
case A:
if(sz != 4)
throw malformed_packet();
addr = IPv4Address(*(uint32_t*)ptr).to_string();
break;
case NS:
case CNAME:
case DNAM:
case PTR:
case MX:
compose_name(ptr, sz, addr);
else
break;
default:
addr.assign(ptr, ptr + sz);
break;
}
res.push_back(
Resource(dname, addr, Endian::be_to_host(it->information().type),
Resource(dname, addr, record_type,
Endian::host_to_be(it->information().qclass),
Endian::be_to_host(it->information().ttl)
)

4
tests/src/dns.cpp
View File

@@ -204,7 +204,7 @@ TEST_F(DNSTest, Question) {
TEST_F(DNSTest, Answers) {
DNS dns;
dns.add_answer("www.example.com", DNS::make_info(DNS::A, DNS::IN, 0x762), IPv4Address("127.0.0.1"));
dns.add_answer("www.example2.com", DNS::make_info(DNS::MX, DNS::IN, 0x762), IPv4Address("127.0.0.1"));
dns.add_answer("www.example2.com", DNS::make_info(DNS::MX, DNS::IN, 0x762), std::string("mail.example.com"));
ASSERT_EQ(dns.answers_count(), 2);
DNS::resources_type resources = dns.answers();
@@ -219,7 +219,7 @@ TEST_F(DNSTest, Answers) {
else if(it->dname() == "www.example2.com") {
EXPECT_EQ(it->type(), DNS::MX);
EXPECT_EQ(it->ttl(), 0x762);
EXPECT_EQ(it->data(), "127.0.0.1");
EXPECT_EQ(it->data(), "mail.example.com");
EXPECT_EQ(it->query_class(), DNS::IN);
}
}