metasploit-framework/lib/rex/proto/smb/utils.rb

563 lines
15 KiB
Ruby

require 'rex/text'
require 'rex/proto/smb/constants'
module Rex
module Proto
module SMB
class Utils
CONST = Rex::Proto::SMB::Constants
# Creates an access mask for use with the CLIENT.open() call based on a string
def self.open_mode_to_access(str)
access = CONST::OPEN_ACCESS_READ | CONST::OPEN_SHARE_DENY_NONE
str.each_byte { |c|
case [c].pack('C').downcase
when 'w'
access |= CONST::OPEN_ACCESS_READWRITE
end
}
return access
end
# Creates a mode mask for use with the CLIENT.open() call based on a string
def self.open_mode_to_mode(str)
mode = 0
str.each_byte { |c|
case [c].pack('C').downcase
when 'x' # Fail if the file already exists
mode |= CONST::OPEN_MODE_EXCL
when 't' # Truncate the file if it already exists
mode |= CONST::OPEN_MODE_TRUNC
when 'c' # Create the file if it does not exist
mode |= CONST::OPEN_MODE_CREAT
when 'o' # Just open the file, clashes with x
mode |= CONST::OPEN_MODE_OPEN
end
}
return mode
end
# Returns a disposition value for smb.create based on permission string
def self.create_mode_to_disposition(str)
str.each_byte { |c|
case [c].pack('C').downcase
when 'c' # Create the file if it does not exist
return CONST::CREATE_ACCESS_OPENCREATE
when 'o' # Just open the file and fail if it does not exist
return CONST::CREATE_ACCESS_EXIST
end
}
return CONST::CREATE_ACCESS_OPENCREATE
end
# Convert a 64-bit signed SMB time to a unix timestamp
def self.time_smb_to_unix(thi, tlo)
(((thi << 32) + tlo) / 10000000) - 11644473600
end
# Convert a unix timestamp to a 64-bit signed server time
def self.time_unix_to_smb(unix_time)
t64 = (unix_time + 11644473600) * 10000000
thi = (t64 & 0xffffffff00000000) >> 32
tlo = (t64 & 0x00000000ffffffff)
return [thi, tlo]
end
# Convert a name to its NetBIOS equivalent
def self.nbname_encode(str)
encoded = ''
for x in (0..15)
if (x >= str.length)
encoded << 'CA'
else
c = str[x, 1].upcase[0,1].unpack('C*')[0]
encoded << [ (c / 16) + 0x41, (c % 16) + 0x41 ].pack('CC')
end
end
return encoded
end
# Convert a name from its NetBIOS equivalent
def self.nbname_decode(str)
decoded = ''
str << 'A' if str.length % 2 != 0
while (str.length > 0)
two = str.slice!(0, 2).unpack('C*')
if (two.length == 2)
decoded << [ ((two[0] - 0x41) * 16) + two[1] - 0x41 ].pack('C')
end
end
return decoded
end
#
# Prepends an ASN1 formatted length field to a piece of data
#
def self.asn1encode(str = '')
res = ''
# If the high bit of the first byte is 1, it contains the number of
# length bytes that follow
case str.length
when 0 .. 0x7F
res = [str.length].pack('C') + str
when 0x80 .. 0xFF
res = [0x81, str.length].pack('CC') + str
when 0x100 .. 0xFFFF
res = [0x82, str.length].pack('Cn') + str
when 0x10000 .. 0xffffff
res = [0x83, str.length >> 16, str.length & 0xFFFF].pack('CCn') + str
when 0x1000000 .. 0xffffffff
res = [0x84, str.length].pack('CN') + str
else
raise "ASN1 str too long"
end
return res
end
def self.make_ntlmv2_secblob_init(domain = 'WORKGROUP', name = 'WORKSTATION', flags=0x80201)
blob =
"\x60" + self.asn1encode(
"\x06" + self.asn1encode(
"\x2b\x06\x01\x05\x05\x02"
) +
"\xa0" + self.asn1encode(
"\x30" + self.asn1encode(
"\xa0" + self.asn1encode(
"\x30" + self.asn1encode(
"\x06" + self.asn1encode(
"\x2b\x06\x01\x04\x01\x82\x37\x02\x02\x0a"
)
)
) +
"\xa2" + self.asn1encode(
"\x04" + self.asn1encode(
"NTLMSSP\x00" +
[1, flags].pack('VV') +
[
domain.length, #length
domain.length, #max length
32
].pack('vvV') +
[
name.length, #length
name.length, #max length
domain.length + 32
].pack('vvV') +
domain + name
)
)
)
)
)
return blob
end
def self.make_ntlmv2_secblob_auth(domain, name, user, lmv2, ntlm, flags = 0x080201)
lmv2 ||= "\x00" * 24
ntlm ||= "\x00" * 24
domain_uni = Rex::Text.to_unicode(domain)
user_uni = Rex::Text.to_unicode(user)
name_uni = Rex::Text.to_unicode(name)
session = ''
ptr = 64
blob =
"\xa1" + self.asn1encode(
"\x30" + self.asn1encode(
"\xa2" + self.asn1encode(
"\x04" + self.asn1encode(
"NTLMSSP\x00" +
[ 3 ].pack('V') +
[ # Lan Manager Response
lmv2.length,
lmv2.length,
(ptr)
].pack('vvV') +
[ # NTLM Manager Response
ntlm.length,
ntlm.length,
(ptr += lmv2.length)
].pack('vvV') +
[ # Domain Name
domain_uni.length,
domain_uni.length,
(ptr += ntlm.length)
].pack('vvV') +
[ # Username
user_uni.length,
user_uni.length,
(ptr += domain_uni.length)
].pack('vvV') +
[ # Hostname
name_uni.length,
name_uni.length,
(ptr += user_uni.length)
].pack('vvV') +
[ # Session Key (none)
session.length,
session.length,
(ptr += name_uni.length)
].pack('vvV') +
[ flags ].pack('V') +
lmv2 +
ntlm +
domain_uni +
user_uni +
name_uni +
session + "\x00"
)
)
)
)
return blob
end
def self.make_negotiate_secblob_resp(account, domain)
blob =
"\x60" + self.asn1encode(
"\x06" + self.asn1encode(
"\x2b\x06\x01\x05\x05\x02"
) +
"\xa0" + self.asn1encode(
"\x30" + self.asn1encode(
"\xa0" + self.asn1encode(
"\x30" + self.asn1encode(
"\x06" + self.asn1encode(
"\x2a\x86\x48\x82\xf7\x12\x01\x02\x02"
) +
"\x06" + self.asn1encode(
"\x2a\x86\x48\x86\xf7\x12\x01\x02\x02"
) +
"\x06" + self.asn1encode(
"\x2a\x86\x48\x86\xf7\x12\x01\x02\x02\x03"
) +
"\x06" + self.asn1encode(
"\x2b\x06\x01\x04\x01\x82\x37\x02\x02\x0a"
)
)
) +
"\xa3" + self.asn1encode(
"\x30" + self.asn1encode(
"\xa0" + self.asn1encode(
"\x1b" + self.asn1encode(
account + '@' + domain
)
)
)
)
)
)
)
return blob
end
def self.make_ntlmv2_secblob_chall(win_domain, dns_domain, win_name, dns_name, chall, flags)
win_domain = Rex::Text.to_unicode(win_domain)
dns_domain = Rex::Text.to_unicode(dns_domain)
win_name = Rex::Text.to_unicode(win_name)
dns_name = Rex::Text.to_unicode(dns_name)
addr_list = ''
addr_list << [2, win_domain.length].pack('vv') + win_domain
addr_list << [1, win_name.length].pack('vv') + win_name
addr_list << [4, dns_domain.length].pack('vv') + dns_domain
addr_list << [3, dns_name.length].pack('vv') + dns_name
addr_list << [5, dns_domain.length].pack('vv') + dns_domain
addr_list << [0, 0].pack('vv')
ptr = 0
blob =
"\xa1" + self.asn1encode(
"\x30" + self.asn1encode(
"\xa0" + self.asn1encode(
"\x0a" + self.asn1encode(
"\x01"
)
) +
"\xa1" + self.asn1encode(
"\x06" + self.asn1encode(
"\x2b\x06\x01\x04\x01\x82\x37\x02\x02\x0a"
)
) +
"\xa2" + self.asn1encode(
"\x04" + self.asn1encode(
"NTLMSSP\x00" +
[2].pack('V') +
[
win_domain.length, # length
win_domain.length, # max length
(ptr += 48)
].pack('vvV') +
[ flags ].pack('V') +
chall +
"\x00\x00\x00\x00\x00\x00\x00\x00" +
[
addr_list.length, # length
addr_list.length, # max length
(ptr += win_domain.length)
].pack('vvV') +
win_domain +
addr_list
)
)
)
)
return blob
end
def self.make_ntlmv2_secblob_success
blob =
"\xa1" + self.asn1encode(
"\x30" + self.asn1encode(
"\xa0" + self.asn1encode(
"\x0a" + self.asn1encode(
"\x00"
)
)
)
)
return blob
end
#
# Process Type 3 NTLM Message (in Base64)
#
# from http://www.innovation.ch/personal/ronald/ntlm.html
#
# struct {
# byte protocol[8]; // 'N', 'T', 'L', 'M', 'S', 'S', 'P', '\0'
# byte type; // 0x03
# byte zero[3];
#
# short lm_resp_len; // LanManager response length (always 0x18)
# short lm_resp_len; // LanManager response length (always 0x18)
# short lm_resp_off; // LanManager response offset
# byte zero[2];
#
# short nt_resp_len; // NT response length (always 0x18)
# short nt_resp_len; // NT response length (always 0x18)
# short nt_resp_off; // NT response offset
# byte zero[2];
#
# short dom_len; // domain string length
# short dom_len; // domain string length
# short dom_off; // domain string offset (always 0x40)
# byte zero[2];
#
# short user_len; // username string length
# short user_len; // username string length
# short user_off; // username string offset
# byte zero[2];
#
# short host_len; // host string length
# short host_len; // host string length
# short host_off; // host string offset
# byte zero[6];
#
# short msg_len; // message length
# byte zero[2];
#
# short flags; // 0x8201
# byte zero[2];
#
# byte dom[*]; // domain string (unicode UTF-16LE)
# byte user[*]; // username string (unicode UTF-16LE)
# byte host[*]; // host string (unicode UTF-16LE)
# byte lm_resp[*]; // LanManager response
# byte nt_resp[*]; // NT response
# } type_3_message
#
def self.process_type3_message(message)
decode = Rex::Text.decode_base64(message.strip)
type = decode[8,1].unpack("C").first
if (type == 3)
lm_len = decode[12,2].unpack("v").first
lm_offset = decode[16,2].unpack("v").first
lm = decode[lm_offset, lm_len].unpack("H*").first
nt_len = decode[20,2].unpack("v").first
nt_offset = decode[24,2].unpack("v").first
nt = decode[nt_offset, nt_len].unpack("H*").first
dom_len = decode[28,2].unpack("v").first
dom_offset = decode[32,2].unpack("v").first
domain = decode[dom_offset, dom_len]
user_len = decode[36,2].unpack("v").first
user_offset = decode[40,2].unpack("v").first
user = decode[user_offset, user_len]
host_len = decode[44,2].unpack("v").first
host_offset = decode[48,2].unpack("v").first
host = decode[host_offset, host_len]
return domain, user, host, lm, nt
else
return "", "", "", "", ""
end
end
#
# Process Type 1 NTLM Messages, return a Base64 Type 2 Message
#
def self.process_type1_message(message, nonce = "\x11\x22\x33\x44\x55\x66\x77\x88", win_domain = 'DOMAIN',
win_name = 'SERVER', dns_name = 'server', dns_domain = 'example.com', downgrade = true)
dns_name = Rex::Text.to_unicode(dns_name + "." + dns_domain)
win_domain = Rex::Text.to_unicode(win_domain)
dns_domain = Rex::Text.to_unicode(dns_domain)
win_name = Rex::Text.to_unicode(win_name)
decode = Rex::Text.decode_base64(message.strip)
type = decode[8,1].unpack("C").first
if (type == 1)
# A type 1 message has been received, lets build a type 2 message response
reqflags = decode[12,4]
reqflags = reqflags.unpack("V").first
if (reqflags & CONST::REQUEST_TARGET) == CONST::REQUEST_TARGET
if (downgrade)
# At this time NTLMv2 and signing requirements are not supported
if (reqflags & CONST::NEGOTIATE_NTLM2_KEY) == CONST::NEGOTIATE_NTLM2_KEY
reqflags = reqflags - CONST::NEGOTIATE_NTLM2_KEY
end
if (reqflags & CONST::NEGOTIATE_ALWAYS_SIGN) == CONST::NEGOTIATE_ALWAYS_SIGN
reqflags = reqflags - CONST::NEGOTIATE_ALWAYS_SIGN
end
end
flags = reqflags + CONST::TARGET_TYPE_DOMAIN + CONST::TARGET_TYPE_SERVER
tid = true
tidoffset = 48 + win_domain.length
tidbuff =
[2].pack('v') + # tid type, win domain
[win_domain.length].pack('v') +
win_domain +
[1].pack('v') + # tid type, server name
[win_name.length].pack('v') +
win_name +
[4].pack('v') + # tid type, domain name
[dns_domain.length].pack('v') +
dns_domain +
[3].pack('v') + # tid type, dns_name
[dns_name.length].pack('v') +
dns_name
else
flags = CONST::NEGOTIATE_UNICODE + CONST::NEGOTIATE_NTLM
tid = false
end
type2msg = "NTLMSSP\0" + # protocol, 8 bytes
"\x02\x00\x00\x00" # type, 4 bytes
if (tid)
type2msg += # Target security info, 8 bytes. Filled if REQUEST_TARGET
[win_domain.length].pack('v') + # Length, 2 bytes
[win_domain.length].pack('v') # Allocated space, 2 bytes
end
type2msg +="\x30\x00\x00\x00" + # Offset, 4 bytes
[flags].pack('V') + # flags, 4 bytes
nonce + # the nonce, 8 bytes
"\x00" * 8 # Context (all 0s), 8 bytes
if (tid)
type2msg += # Target information security buffer. Filled if REQUEST_TARGET
[tidbuff.length].pack('v') + # Length, 2 bytes
[tidbuff.length].pack('v') + # Allocated space, 2 bytes
[tidoffset].pack('V') + # Offset, 4 bytes (usually \x48 + length of win_domain)
win_domain + # Target name data (domain in unicode if REQUEST_UNICODE)
# Target information data
tidbuff + # Type, 2 bytes
# Length, 2 bytes
# Data (in unicode if REQUEST_UNICODE)
"\x00\x00\x00\x00" # Terminator, 4 bytes, all \x00
end
type2msg = Rex::Text.encode_base64(type2msg).delete("\n") # base64 encode and remove the returns
else
# This is not a Type2 message
type2msg = ""
end
return type2msg
end
#
# Downgrading Type messages to LMv1/NTLMv1 and removing signing
#
def self.downgrade_type_message(message)
decode = Rex::Text.decode_base64(message.strip)
type = decode[8,1].unpack("C").first
if (type > 0 and type < 4)
reqflags = decode[12..15] if (type == 1 or type == 3)
reqflags = decode[20..23] if (type == 2)
reqflags = reqflags.unpack("V")
# Remove NEGOTIATE_NTLMV2_KEY and NEGOTIATE_ALWAYS_SIGN, this lowers the negotiation
# down to LMv1/NTLMv1.
if (reqflags & CONST::NEGOTIATE_NTLM2_KEY) == CONST::NEGOTIATE_NTLM2_KEY
reqflags = reqflags - CONST::NEGOTIATE_NTLM2_KEY
end
if (reqflags & CONST::NEGOTIATE_ALWAYS_SIGN) == CONST::NEGOTIATE_ALWAYS_SIGN
reqflags = reqflags - CONST::NEGOTIATE_ALWAYS_SIGN
end
# Return the flags back to the decode so we can base64 it again
flags = reqflags.to_s(16)
0.upto(8) do |idx|
if (idx > flags.length)
flags.insert(0, "0")
end
end
idx = 0
0.upto(3) do |cnt|
if (type == 2)
decode[23-cnt] = [flags[idx,1]].pack("C")
else
decode[15-cnt] = [flags[idx,1]].pack("C")
end
idx += 2
end
end
return Rex::Text.encode_base64(decode).delete("\n") # base64 encode and remove the returns
end
end
end
end
end