def test_response_cname():
dns = DNSHeader.parse(
'\x83-' # identification
'\x81\x80' # flags and codes
'\x00\x01' # total questions
'\x00\x01' # total answers
'\x00\x00' # total authority RRs
'\x00\x00' # total additional RRs
# question RR - IN CNAME www.slackware.it
'\x03www\tslackware\x02it\x00' '\x00\x05' '\x00\x01'
# compression ptr - type CNAME - class IN
'\xc0\x0c' '\x00\x05' '\x00\x01'
'\x00\x00\x01\x13\x00\x02\xc0\x10'
)
# check questions
assert dns.total_questions == 1
assert len(dns.questions) == 1
assert dns.questions[0].qname == ['www', 'slackware', 'it', '']
# check answers
assert dns.total_answer_rrs == 1
assert len(dns.answers) == 1
answer = dns.answers[0]
assert answer.name == ['www', 'slackware', 'it', '']
assert answer.type == 'CNAME'
assert answer['class'] == 'IN'
assert answer.ttl == 275
assert answer.rdlength == 2 # it's a pointer
rr = answer.rdata
assert rr.name == ['slackware', 'it', '']
def test_answer_txt():
dns = DNSHeader.parse(
'\x102' # identification
'\x81\x80' # flags and codes
'\x00\x01' # total questions
'\x00\x01' # total answers
'\x00\x00' # total authority RRs
'\x00\x00' # total additional RRs
# question RR - IN TXT google.com
'\x06google\x03com\x00' '\x00\x10' '\x00\x01'
# answer RR - no compression
'\x06google\x03com\x00\x00\x10\x00\x01\x00\x00\x01'
'\x0e\x00\x10\x0fv=spf1 ptr ?all'
)
assert dns.identification == 4146
assert dns.total_questions == 1
assert dns.total_answer_rrs == 1
assert len(dns.answers) == 1
assert dns.answers[0].rdata == 'v=spf1 ptr ?all'
def test_request_dns_compression():
packet = (
'\x97\xc9' # identification
'\x81\x80' # flags and codes
'\x00\x01' # total questions
'\x00\x06' # total answer RRs
'\x00\x00' # total authority RRs
'\x00\x00' # total additional RRs
# questions
'\x06google\x03com\x00' # qname
'\x00\x01' # qtype
'\x00\x01' # qclass
# Answers
# answer #1
'\xc0\x0c' # pointer to absolute offset 0x0c
'\x00\x01' # type A
'\x00\x01' # class IN
'\x00\x00\x01\x16' # ttl 278
'\x00\x04' # rdlength
'J}\x18q' # rdata, IP address
# answer #2
'\xc0\x0c' # pointer to absolute offset 0x0c
'\x00\x01' # type A
'\x00\x01' # class IN
'\x00\x00\x01\x16' # ttl 278
'\x00\x04' # rdlength
'J}\x18f' # rdata, IP address
# answer #3
'\xc0\x0c' # pointer to absolute offset 0x0c
'\x00\x01' # type A
'\x00\x01' # class IN
'\x00\x00\x01\x16' # ttl 278
'\x00\x04' # rdlength
'J}\x18\x8a' # rdata, IP address
# answer #4
'\xc0\x0c' # pointer to absolute offset 0x0c
'\x00\x01' # type A
'\x00\x01' # class IN
'\x00\x00\x01\x16' # ttl 278
'\x00\x04' # rdlength
'J}\x18\x8b' # rdata, IP address
# answer #5
'\xc0\x0c' # pointer to absolute offset 0x0c
'\x00\x01' # type A
'\x00\x01' # class IN
'\x00\x00\x01\x16' # ttl 278
'\x00\x04' # rdlength
'J}\x18d' # rdata, IP address
# answer #6
'\xc0\x0c' # pointer to absolute offset 0x0c
'\x00\x01' # type A
'\x00\x01' # class IN
'\x00\x00\x01\x16' # ttl 278
'\x00\x04' # rdlength
'J}\x18e' # rdata, IP address
)
dns = DNSHeader.parse(packet)
# check questions
assert len(dns.questions) == 1
question = dns.questions[0]
assert question.qtype == 'A'
assert question.qclass == 'IN'
assert question.qname == ['google', 'com', '']
# check answer RRs
assert len(dns.answers) == 6
answer0 = dns.answers[0]
assert answer0.name == ['google', 'com', '']
assert answer0.ttl == 278
assert answer0.type == 'A'
assert answer0['class'] == 'IN'
assert answer0.rdlength == 4
assert answer0.rdata == '74.125.24.113'
answer1 = dns.answers[1]
assert answer1.name == ['google', 'com', '']
assert answer1.ttl == 278
assert answer1.type == 'A'
assert answer1['class'] == 'IN'
assert answer1.rdlength == 4
assert answer1.rdata == '74.125.24.102'
answer2 = dns.answers[2]
assert answer2.name == ['google', 'com', '']
assert answer2.ttl == 278
assert answer2.type == 'A'
assert answer2['class'] == 'IN'
assert answer2.rdlength == 4
assert answer2.rdata == '74.125.24.138'
answer3 = dns.answers[3]
assert answer3.name == ['google', 'com', '']
assert answer3.ttl == 278
assert answer3.type == 'A'
assert answer3['class'] == 'IN'
assert answer3.rdlength == 4
assert answer3.rdata == '74.125.24.139'
answer4 = dns.answers[4]
assert answer4.name == ['google', 'com', '']
assert answer4.ttl == 278
assert answer4.type == 'A'
assert answer4['class'] == 'IN'
assert answer4.rdlength == 4
assert answer4.rdata == '74.125.24.100'
answer5 = dns.answers[5]
assert answer5.name == ['google', 'com', '']
assert answer5.ttl == 278
assert answer5.type == 'A'
assert answer5['class'] == 'IN'
assert answer5.rdlength == 4
assert answer5.rdata == '74.125.24.101'
# check authority RRs
assert len(dns.authority) == 0
# check additional RRs
assert len(dns.additional) == 0