Test: Full TLS test cycle including sending certificate verify and validating server authentication.
Change-Id: I0cdb16b8ec6f94fefc71742d844fe473b932d103
diff --git a/src/test/utils/EapTLS.py b/src/test/utils/EapTLS.py
index 8a3e1c7..b5aad78 100644
--- a/src/test/utils/EapTLS.py
+++ b/src/test/utils/EapTLS.py
@@ -19,8 +19,9 @@
import noseTlsAuthHolder as tlsAuthHolder
from scapy_ssl_tls.ssl_tls import *
from scapy_ssl_tls.ssl_tls_crypto import *
+from tls_cert import Key
from socket import *
-from struct import *
+import struct
import scapy
from nose.tools import *
from CordTestBase import CordTester
@@ -56,7 +57,8 @@
server_hello_done_signature = '\x0e\x00\x00\x00'
SERVER_HELLO = '\x02'
SERVER_CERTIFICATE = '\x0b'
- SERVER_HELLO_DONE = '\x0d'
+ CERTIFICATE_REQUEST = '\x0d'
+ SERVER_HELLO_DONE = '\x0e'
SERVER_UNKNOWN = '\xff'
HANDSHAKE = '\x16'
CHANGE_CIPHER = '\x14'
@@ -64,30 +66,41 @@
HDR_IDX = 0
DATA_IDX = 1
CB_IDX = 2
+
CLIENT_CERT = """-----BEGIN CERTIFICATE-----
-MIIDvTCCAqWgAwIBAgIBAjANBgkqhkiG9w0BAQUFADCBizELMAkGA1UEBhMCVVMx
+MIICuDCCAiGgAwIBAgIBAjANBgkqhkiG9w0BAQUFADCBizELMAkGA1UEBhMCVVMx
CzAJBgNVBAgTAkNBMRIwEAYDVQQHEwlTb21ld2hlcmUxEzARBgNVBAoTCkNpZW5h
IEluYy4xHjAcBgkqhkiG9w0BCQEWD2FkbWluQGNpZW5hLmNvbTEmMCQGA1UEAxMd
-RXhhbXBsZSBDZXJ0aWZpY2F0ZSBBdXRob3JpdHkwHhcNMTYwMzExMTg1MzM2WhcN
-MTcwMzA2MTg1MzM2WjBnMQswCQYDVQQGEwJVUzELMAkGA1UECBMCQ0ExEzARBgNV
+RXhhbXBsZSBDZXJ0aWZpY2F0ZSBBdXRob3JpdHkwHhcNMTYwNjA2MjExMjI3WhcN
+MTcwNjAxMjExMjI3WjBnMQswCQYDVQQGEwJVUzELMAkGA1UECBMCQ0ExEzARBgNV
BAoTCkNpZW5hIEluYy4xFzAVBgNVBAMUDnVzZXJAY2llbmEuY29tMR0wGwYJKoZI
-hvcNAQkBFg51c2VyQGNpZW5hLmNvbTCCASIwDQYJKoZIhvcNAQEBBQADggEPADCC
-AQoCggEBAOxemcBsPn9tZsCa5o2JA6sQDC7A6JgCNXXl2VFzKLNNvB9PS6D7ZBsQ
-5An0zEDMNzi51q7lnrYg1XyiE4S8FzMGAFr94RlGMQJUbRD9V/oqszMX4k++iAOK
-tIA1gr3x7Zi+0tkjVSVzXTmgNnhChAamdMsjYUG5+CY9WAicXyy+VEV3zTphZZDR
-OjcjEp4m/TSXVPYPgYDXI40YZKX5BdvqykWtT/tIgZb48RS1NPyN/XkCYzl3bv21
-qx7Mc0fcEbsJBIIRYTUkfxnsilcnmLxSYO+p+DZ9uBLBzcQt+4Rd5pLSfi21WM39
-2Z2oOi3vs/OYAPAqgmi2JWOv3mePa/8CAwEAAaNPME0wEwYDVR0lBAwwCgYIKwYB
-BQUHAwIwNgYDVR0fBC8wLTAroCmgJ4YlaHR0cDovL3d3dy5leGFtcGxlLmNvbS9l
-eGFtcGxlX2NhLmNybDANBgkqhkiG9w0BAQUFAAOCAQEALBzMPDTIB6sLyPl0T6JV
-MjOkyldAVhXWiQsTjaGQGJUUe1cmUJyZbUZEc13MygXMPOM4x7z6VpXGuq1c/Vxn
-VzQ2fNnbJcIAHi/7G8W5/SQfPesIVDsHTEc4ZspPi5jlS/MVX3HOC+BDbOjdbwqP
-RX0JEr+uOyhjO+lRxG8ilMRACoBUbw1eDuVDoEBgErSUC44pq5ioDw2xelc+Y6hQ
-dmtYwfY0DbvwxHtA495frLyPcastDiT/zre7NL51MyUDPjjYjghNQEwvu66IKbQ3
-T1tJBrgI7/WI+dqhKBFolKGKTDWIHsZXQvZ1snGu/FRYzg1l+R/jT8cRB9BDwhUt
-yg==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-----END CERTIFICATE-----"""
+ CLIENT_PRIV_KEY = """-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----"""
+
def handle_server_hello_done(self, server_hello_done):
if server_hello_done[-4:] == self.server_hello_done_signature:
self.server_hello_done_received = True
@@ -109,13 +122,20 @@
self.pkt_history = []
self.pkt_map = { self.SERVER_HELLO: ['', '', lambda pkt: pkt ],
self.SERVER_CERTIFICATE: ['', '', lambda pkt: pkt ],
+ self.CERTIFICATE_REQUEST: ['', '', lambda pkt: pkt ],
self.SERVER_HELLO_DONE: ['', '', self.handle_server_hello_done ],
self.SERVER_UNKNOWN: ['', '', lambda pkt: pkt ]
}
self.tls_ctx = TLSSessionCtx(client = True)
def load_tls_record(self, data, pkt_type = ''):
- if pkt_type not in [ self.SERVER_HELLO_DONE, self.SERVER_UNKNOWN ]:
+ #if pkt_type not in [ self.SERVER_HELLO_DONE, self.SERVER_UNKNOWN ]:
+ if pkt_type == self.SERVER_HELLO_DONE:
+ data = str(TLSRecord(content_type=TLSContentType.HANDSHAKE)/data)
+ elif pkt_type == self.CERTIFICATE_REQUEST:
+ data = str(TLSRecord()/TLSHandshake(type=TLSHandshakeType.CERTIFICATE_REQUEST)/data[9:])
+ data = None #For now ignore this record
+ if data:
TLS(data, ctx = self.tls_ctx)
def pkt_update(self, pkt_type, data, hdr=None, reassembled = False):
@@ -139,6 +159,7 @@
r = str(pkt)
offset = self.TLS_OFFSET
tls_data = r[offset:]
+ type_hdrlen = 0
if self.pending_bytes > 0:
if len(tls_data) >= self.pending_bytes:
self.pkt_update(self.pkt_last, tls_data[:self.pending_bytes], reassembled = True)
@@ -154,9 +175,13 @@
self.pending_bytes = bytes_to_num(tls_data[3:5])
if tls_data[0] == self.HANDSHAKE:
pkt_type = tls_data[5]
- if len(tls_data) - 5 >= self.pending_bytes:
- data_received = tls_data[5: 5 + self.pending_bytes]
- offset += 5 + self.pending_bytes
+ if pkt_type in [ self.CERTIFICATE_REQUEST ]:
+ self.pending_bytes = bytes_to_num(tls_data[6:9])
+ type_hdrlen = 4
+ if len(tls_data) - 5 - type_hdrlen >= self.pending_bytes:
+ data_received = tls_data[5: 5 + type_hdrlen + self.pending_bytes ]
+ offset += 5 + type_hdrlen + self.pending_bytes
+ type_hdrlen = 0
self.pending_bytes = 0
self.pkt_update(pkt_type, data_received,
hdr = tls_data[:5],
@@ -165,10 +190,13 @@
self.pkt_update(pkt_type, tls_data[5:],
hdr = tls_data[:5],
reassembled = False)
- self.pending_bytes -= len(tls_data) - 5
+ self.pending_bytes -= len(tls_data) - 5 - type_hdrlen
self.pkt_last = pkt_type
log.info('Pending bytes left %d' %(self.pending_bytes))
assert self.pending_bytes > 0
+ elif tls_data[0] == self.SERVER_HELLO_DONE:
+ self.pkt_update(tls_data[0], tls_data, reassembled = True)
+ break
else:
self.pkt_last = self.SERVER_UNKNOWN
if len(tls_data) - 5 >= self.pending_bytes:
@@ -210,11 +238,12 @@
gmt_unix_time=1234,
random_bytes= '\xAB' * 28,
session_id='',
- compression_methods=(TLSCompressionMethod.NULL),
+ compression_methods=[TLSCompressionMethod.NULL],
cipher_suites=[TLSCipherSuite.RSA_WITH_AES_256_CBC_SHA]
)
- self.pkt_history.append( str(self.client_hello) )
- reqdata = TLSRecord()/TLSHandshake()/self.client_hello
+ client_hello_data = TLSHandshake()/self.client_hello
+ self.pkt_history.append( str(client_hello_data) )
+ reqdata = TLSRecord()/client_hello_data
self.load_tls_record(str(reqdata))
log.info("Sending Client Hello TLS payload of len %d, id %d" %(len(reqdata),pkt[EAP].id))
eap_payload = self.eapTLS(EAP_RESPONSE, pkt[EAP].id, TLS_LENGTH_INCLUDED, str(reqdata))
@@ -231,15 +260,31 @@
##send cert request when we receive the last server hello fragment
self.nextEvent = self.tlsEventTable.EVT_EAP_TLS_CERT_REQ
- def get_encrypted_handshake_msg(self, finish_val=''):
+ def get_verify_data(self):
all_handshake_pkts = ''.join(self.pkt_history)
+ return self.tls_ctx.get_verify_data(data = all_handshake_pkts)
+
+ def get_verify_signature(self, pem_data):
+ all_handshake_pkts = ''.join(self.pkt_history)
+ k = Key(pem_data)
+ signature = k.sign(all_handshake_pkts, t = 'pkcs', h = 'tls')
+ signature_data = '{}{}'.format(struct.pack('!H', len(signature)), signature)
+ return signature_data
+
+ def get_encrypted_handshake_msg(self, finish_val=''):
if not finish_val:
- finish_val = self.tls_ctx.get_verify_data(data = all_handshake_pkts)
+ finish_val = self.get_verify_data()
msg = str(TLSHandshake(type=TLSHandshakeType.FINISHED)/finish_val)
crypto_container = CryptoContainer(self.tls_ctx, data = msg,
content_type = TLSContentType.HANDSHAKE)
return crypto_container.encrypt()
+ def get_encrypted_application_msg(self, msg = ''):
+ '''Needed with tunneled TLS'''
+ if not msg:
+ msg = 'test data'
+ return to_raw(TLSPlaintext(data = 'GET / HTTP/1.1\r\nHOST: localhost\r\n\r\n'), self.tls_ctx)
+
def _eapTlsCertReq(self):
def eapol_cb(pkt):
@@ -249,21 +294,28 @@
assert self.server_hello_done_received == True
rex_pem = re.compile(r'\-+BEGIN[^\-]+\-+(.*?)\-+END[^\-]+\-+', re.DOTALL)
der_cert = rex_pem.findall(self.CLIENT_CERT)[0].decode("base64")
- client_certificate = TLSRecord(version="TLS_1_0")/TLSHandshake()/TLSCertificateList(
+ client_certificate_list = TLSHandshake()/TLSCertificateList(
certificates=[TLSCertificate(data=x509.X509Cert(der_cert))])
+ client_certificate = TLSRecord(version="TLS_1_0")/client_certificate_list
kex_data = self.tls_ctx.get_client_kex_data()
- client_key_ex = TLSRecord()/TLSHandshake()/kex_data
- client_key_ex_data = str(TLSHandshake()/kex_data)
- self.pkt_history.append(client_key_ex_data)
+ client_key_ex_data = TLSHandshake()/kex_data
+ client_key_ex = TLSRecord()/client_key_ex_data
+ self.load_tls_record(str(client_certificate))
self.load_tls_record(str(client_key_ex))
+ self.pkt_history.append(str(client_certificate_list))
+ self.pkt_history.append(str(client_key_ex_data))
+ verify_signature = self.get_verify_signature(self.CLIENT_PRIV_KEY)
+ client_cert_verify = TLSHandshake(type=TLSHandshakeType.CERTIFICATE_VERIFY)/verify_signature
+ client_cert_record = TLSRecord(content_type=TLSContentType.HANDSHAKE)/client_cert_verify
+ self.pkt_history.append(str(client_cert_verify))
#log.info('TLS ctxt: %s' %self.tls_ctx)
client_ccs = TLSRecord(version="TLS_1_0")/TLSChangeCipherSpec()
enc_handshake_msg = self.get_encrypted_handshake_msg()
handshake_msg = str(TLSRecord(content_type=TLSContentType.HANDSHAKE)/enc_handshake_msg)
- reqdata = str(TLS.from_records( [client_certificate, client_key_ex, client_ccs] ))
+ reqdata = str(TLS.from_records([client_certificate, client_key_ex, client_cert_record, client_ccs]))
reqdata += handshake_msg
log.info("------> Sending Client Hello TLS Certificate payload of len %d ----------->" %len(reqdata))
- eap_payload = self.eapTLS(EAP_RESPONSE, pkt[EAP].id, TLS_LENGTH_INCLUDED, str(reqdata))
+ eap_payload = self.eapTLS(EAP_RESPONSE, pkt[EAP].id, TLS_LENGTH_INCLUDED, reqdata)
self.eapol_send(EAPOL_EAPPACKET, eap_payload)
self.eapol_scapy_recv(cb = eapol_cb,
@@ -274,9 +326,12 @@
def _eapTlsChangeCipherSpec(self):
def eapol_cb(pkt):
r = str(pkt)
- tls_data = r[TLS_OFFSET:]
+ tls_data = r[self.TLS_OFFSET:]
log.info('Verifying TLS Change Cipher spec record type %x' %ord(tls_data[0]))
assert tls_data[0] == self.CHANGE_CIPHER
+ log.info('Handshake finished. Sending empty data')
+ eap_payload = self.eapTLS(EAP_RESPONSE, pkt[EAP].id, 0, '')
+ self.eapol_send(EAPOL_EAPPACKET, eap_payload)
self.eapol_scapy_recv(cb = eapol_cb,
lfilter =
@@ -286,10 +341,10 @@
def _eapTlsFinished(self):
def eapol_cb(pkt):
- log.info('Got Server finished')
+ log.info('Server authentication successfull')
self.eapol_scapy_recv(cb = eapol_cb,
lfilter =
- lambda pkt: EAP in pkt and pkt[EAP].type == EAP_TYPE_TLS and pkt[EAP].code == EAP.REQUEST)
- #We stop here as certification validation success implies auth success
+ lambda pkt: EAP in pkt and pkt[EAP].code == EAP.SUCCESS)
+ self.eapol_logoff()
self.nextEvent = None
diff --git a/src/test/utils/EapolAAA.py b/src/test/utils/EapolAAA.py
index 419c7e3..a897833 100644
--- a/src/test/utils/EapolAAA.py
+++ b/src/test/utils/EapolAAA.py
@@ -102,6 +102,10 @@
eap_payload = self.eap(EAPOL_START, 2)
return self.eapol_send(EAPOL_START, eap_payload)
+ def eapol_logoff(self):
+ eap_payload = self.eap(EAPOL_LOGOFF, 2)
+ return self.eapol_send(EAPOL_LOGOFF, eap_payload)
+
def eapol_id_req(self, pkt_id = 0, user = USER):
eap_payload = self.eap(EAP_RESPONSE, pkt_id, EAP_TYPE_ID, user)
return self.eapol_send(EAPOL_EAPPACKET, eap_payload)
diff --git a/src/test/utils/tls_cert.py b/src/test/utils/tls_cert.py
new file mode 100644
index 0000000..68726e0
--- /dev/null
+++ b/src/test/utils/tls_cert.py
@@ -0,0 +1,1060 @@
+## This file is part of Scapy
+## See http://www.secdev.org/projects/scapy for more informations
+## Copyright (C) Arnaud Ebalard <arno@natisbad.org>
+## This program is published under a GPLv2 license
+
+"""
+Cryptographic certificates.
+"""
+
+import os, sys, math, struct, random
+from scapy.utils import strxor
+from scapy_ssl_tls.ssl_tls_crypto import x509_extract_pubkey_from_der
+try:
+ HAS_HASHLIB=True
+ import hashlib
+except:
+ HAS_HASHLIB=False
+
+from Crypto.PublicKey import *
+from Crypto.Cipher import *
+from Crypto.Hash import *
+from Crypto.Util import number
+
+# Maximum allowed size in bytes for a certificate file, to avoid
+# loading huge file when importing a cert
+MAX_KEY_SIZE=50*1024
+
+#####################################################################
+# Some helpers
+#####################################################################
+
+def warning(m):
+ print "WARNING: %s" % m
+
+def randstring(l):
+ """
+ Returns a random string of length l (l >= 0)
+ """
+ tmp = map(lambda x: struct.pack("B", random.randrange(0, 256, 1)), [""]*l)
+ return "".join(tmp)
+
+def zerofree_randstring(l):
+ """
+ Returns a random string of length l (l >= 0) without zero in it.
+ """
+ tmp = map(lambda x: struct.pack("B", random.randrange(1, 256, 1)), [""]*l)
+ return "".join(tmp)
+
+def strand(s1, s2):
+ """
+ Returns the binary AND of the 2 provided strings s1 and s2. s1 and s2
+ must be of same length.
+ """
+ return "".join(map(lambda x,y:chr(ord(x)&ord(y)), s1, s2))
+
+# OS2IP function defined in RFC 3447 for octet string to integer conversion
+def pkcs_os2ip(x):
+ """
+ Accepts a byte string as input parameter and return the associated long
+ value:
+
+ Input : x octet string to be converted
+
+ Output: x corresponding nonnegative integer
+
+ Reverse function is pkcs_i2osp()
+ """
+ return number.bytes_to_long(x)
+
+# IP2OS function defined in RFC 3447 for octet string to integer conversion
+def pkcs_i2osp(x,xLen):
+ """
+ Converts a long (the first parameter) to the associated byte string
+ representation of length l (second parameter). Basically, the length
+ parameters allow the function to perform the associated padding.
+
+ Input : x nonnegative integer to be converted
+ xLen intended length of the resulting octet string
+
+ Output: x corresponding nonnegative integer
+
+ Reverse function is pkcs_os2ip().
+ """
+ z = number.long_to_bytes(x)
+ padlen = max(0, xLen-len(z))
+ return '\x00'*padlen + z
+
+# for every hash function a tuple is provided, giving access to
+# - hash output length in byte
+# - associated hash function that take data to be hashed as parameter
+# XXX I do not provide update() at the moment.
+# - DER encoding of the leading bits of digestInfo (the hash value
+# will be concatenated to create the complete digestInfo).
+#
+# Notes:
+# - MD4 asn.1 value should be verified. Also, as stated in
+# PKCS#1 v2.1, MD4 should not be used.
+# - hashlib is available from http://code.krypto.org/python/hashlib/
+# - 'tls' one is the concatenation of both md5 and sha1 hashes used
+# by SSL/TLS when signing/verifying things
+_hashFuncParams = {
+ "md2" : (16,
+ lambda x: MD2.new(x).digest(),
+ '\x30\x20\x30\x0c\x06\x08\x2a\x86\x48\x86\xf7\x0d\x02\x02\x05\x00\x04\x10'),
+ "md4" : (16,
+ lambda x: MD4.new(x).digest(),
+ '\x30\x20\x30\x0c\x06\x08\x2a\x86\x48\x86\xf7\x0d\x02\x04\x05\x00\x04\x10'), # is that right ?
+ "md5" : (16,
+ lambda x: MD5.new(x).digest(),
+ '\x30\x20\x30\x0c\x06\x08\x2a\x86\x48\x86\xf7\x0d\x02\x05\x05\x00\x04\x10'),
+ "sha1" : (20,
+ lambda x: SHA.new(x).digest(),
+ '\x30\x21\x30\x09\x06\x05\x2b\x0e\x03\x02\x1a\x05\x00\x04\x14'),
+ "tls" : (36,
+ lambda x: MD5.new(x).digest() + SHA.new(x).digest(),
+ '') }
+
+if HAS_HASHLIB:
+ _hashFuncParams["sha224"] = (28,
+ lambda x: hashlib.sha224(x).digest(),
+ '\x30\x2d\x30\x0d\x06\x09\x60\x86\x48\x01\x65\x03\x04\x02\x04\x05\x00\x04\x1c')
+ _hashFuncParams["sha256"] = (32,
+ lambda x: hashlib.sha256(x).digest(),
+ '\x30\x31\x30\x0d\x06\x09\x60\x86\x48\x01\x65\x03\x04\x02\x01\x05\x00\x04\x20')
+ _hashFuncParams["sha384"] = (48,
+ lambda x: hashlib.sha384(x).digest(),
+ '\x30\x41\x30\x0d\x06\x09\x60\x86\x48\x01\x65\x03\x04\x02\x02\x05\x00\x04\x30')
+ _hashFuncParams["sha512"] = (64,
+ lambda x: hashlib.sha512(x).digest(),
+ '\x30\x51\x30\x0d\x06\x09\x60\x86\x48\x01\x65\x03\x04\x02\x03\x05\x00\x04\x40')
+else:
+ warning("hashlib support is not available. Consider installing it")
+ warning("if you need sha224, sha256, sha384 and sha512 algs.")
+
+def pkcs_mgf1(mgfSeed, maskLen, h):
+ """
+ Implements generic MGF1 Mask Generation function as described in
+ Appendix B.2.1 of RFC 3447. The hash function is passed by name.
+ valid values are 'md2', 'md4', 'md5', 'sha1', 'tls, 'sha256',
+ 'sha384' and 'sha512'. Returns None on error.
+
+ Input:
+ mgfSeed: seed from which mask is generated, an octet string
+ maskLen: intended length in octets of the mask, at most 2^32 * hLen
+ hLen (see below)
+ h : hash function name (in 'md2', 'md4', 'md5', 'sha1', 'tls',
+ 'sha256', 'sha384'). hLen denotes the length in octets of
+ the hash function output.
+
+ Output:
+ an octet string of length maskLen
+ """
+
+ # steps are those of Appendix B.2.1
+ if not _hashFuncParams.has_key(h):
+ warning("pkcs_mgf1: invalid hash (%s) provided")
+ return None
+ hLen = _hashFuncParams[h][0]
+ hFunc = _hashFuncParams[h][1]
+ if maskLen > 2**32 * hLen: # 1)
+ warning("pkcs_mgf1: maskLen > 2**32 * hLen")
+ return None
+ T = "" # 2)
+ maxCounter = math.ceil(float(maskLen) / float(hLen)) # 3)
+ counter = 0
+ while counter < maxCounter:
+ C = pkcs_i2osp(counter, 4)
+ T += hFunc(mgfSeed + C)
+ counter += 1
+ return T[:maskLen]
+
+
+def pkcs_emsa_pss_encode(M, emBits, h, mgf, sLen):
+ """
+ Implements EMSA-PSS-ENCODE() function described in Sect. 9.1.1 of RFC 3447
+
+ Input:
+ M : message to be encoded, an octet string
+ emBits: maximal bit length of the integer resulting of pkcs_os2ip(EM),
+ where EM is the encoded message, output of the function.
+ h : hash function name (in 'md2', 'md4', 'md5', 'sha1', 'tls',
+ 'sha256', 'sha384'). hLen denotes the length in octets of
+ the hash function output.
+ mgf : the mask generation function f : seed, maskLen -> mask
+ sLen : intended length in octets of the salt
+
+ Output:
+ encoded message, an octet string of length emLen = ceil(emBits/8)
+
+ On error, None is returned.
+ """
+
+ # 1) is not done
+ hLen = _hashFuncParams[h][0] # 2)
+ hFunc = _hashFuncParams[h][1]
+ mHash = hFunc(M)
+ emLen = int(math.ceil(emBits/8.))
+ if emLen < hLen + sLen + 2: # 3)
+ warning("encoding error (emLen < hLen + sLen + 2)")
+ return None
+ salt = randstring(sLen) # 4)
+ MPrime = '\x00'*8 + mHash + salt # 5)
+ H = hFunc(MPrime) # 6)
+ PS = '\x00'*(emLen - sLen - hLen - 2) # 7)
+ DB = PS + '\x01' + salt # 8)
+ dbMask = mgf(H, emLen - hLen - 1) # 9)
+ maskedDB = strxor(DB, dbMask) # 10)
+ l = (8*emLen - emBits)/8 # 11)
+ rem = 8*emLen - emBits - 8*l # additionnal bits
+ andMask = l*'\x00'
+ if rem:
+ j = chr(reduce(lambda x,y: x+y, map(lambda x: 1<<x, range(8-rem))))
+ andMask += j
+ l += 1
+ maskedDB = strand(maskedDB[:l], andMask) + maskedDB[l:]
+ EM = maskedDB + H + '\xbc' # 12)
+ return EM # 13)
+
+
+def pkcs_emsa_pss_verify(M, EM, emBits, h, mgf, sLen):
+ """
+ Implements EMSA-PSS-VERIFY() function described in Sect. 9.1.2 of RFC 3447
+
+ Input:
+ M : message to be encoded, an octet string
+ EM : encoded message, an octet string of length emLen = ceil(emBits/8)
+ emBits: maximal bit length of the integer resulting of pkcs_os2ip(EM)
+ h : hash function name (in 'md2', 'md4', 'md5', 'sha1', 'tls',
+ 'sha256', 'sha384'). hLen denotes the length in octets of
+ the hash function output.
+ mgf : the mask generation function f : seed, maskLen -> mask
+ sLen : intended length in octets of the salt
+
+ Output:
+ True if the verification is ok, False otherwise.
+ """
+
+ # 1) is not done
+ hLen = _hashFuncParams[h][0] # 2)
+ hFunc = _hashFuncParams[h][1]
+ mHash = hFunc(M)
+ emLen = int(math.ceil(emBits/8.)) # 3)
+ if emLen < hLen + sLen + 2:
+ return False
+ if EM[-1] != '\xbc': # 4)
+ return False
+ l = emLen - hLen - 1 # 5)
+ maskedDB = EM[:l]
+ H = EM[l:l+hLen]
+ l = (8*emLen - emBits)/8 # 6)
+ rem = 8*emLen - emBits - 8*l # additionnal bits
+ andMask = l*'\xff'
+ if rem:
+ val = reduce(lambda x,y: x+y, map(lambda x: 1<<x, range(8-rem)))
+ j = chr(~val & 0xff)
+ andMask += j
+ l += 1
+ if strand(maskedDB[:l], andMask) != '\x00'*l:
+ return False
+ dbMask = mgf(H, emLen - hLen - 1) # 7)
+ DB = strxor(maskedDB, dbMask) # 8)
+ l = (8*emLen - emBits)/8 # 9)
+ rem = 8*emLen - emBits - 8*l # additionnal bits
+ andMask = l*'\x00'
+ if rem:
+ j = chr(reduce(lambda x,y: x+y, map(lambda x: 1<<x, range(8-rem))))
+ andMask += j
+ l += 1
+ DB = strand(DB[:l], andMask) + DB[l:]
+ l = emLen - hLen - sLen - 1 # 10)
+ if DB[:l] != '\x00'*(l-1) + '\x01':
+ return False
+ salt = DB[-sLen:] # 11)
+ MPrime = '\x00'*8 + mHash + salt # 12)
+ HPrime = hFunc(MPrime) # 13)
+ return H == HPrime # 14)
+
+
+def pkcs_emsa_pkcs1_v1_5_encode(M, emLen, h): # section 9.2 of RFC 3447
+ """
+ Implements EMSA-PKCS1-V1_5-ENCODE() function described in Sect.
+ 9.2 of RFC 3447.
+
+ Input:
+ M : message to be encode, an octet string
+ emLen: intended length in octets of the encoded message, at least
+ tLen + 11, where tLen is the octet length of the DER encoding
+ T of a certain value computed during the encoding operation.
+ h : hash function name (in 'md2', 'md4', 'md5', 'sha1', 'tls',
+ 'sha256', 'sha384'). hLen denotes the length in octets of
+ the hash function output.
+
+ Output:
+ encoded message, an octet string of length emLen
+
+ On error, None is returned.
+ """
+ hLen = _hashFuncParams[h][0] # 1)
+ hFunc = _hashFuncParams[h][1]
+ H = hFunc(M)
+ hLeadingDigestInfo = _hashFuncParams[h][2] # 2)
+ T = hLeadingDigestInfo + H
+ tLen = len(T)
+ if emLen < tLen + 11: # 3)
+ warning("pkcs_emsa_pkcs1_v1_5_encode: intended encoded message length too short")
+ return None
+ PS = '\xff'*(emLen - tLen - 3) # 4)
+ EM = '\x00' + '\x01' + PS + '\x00' + T # 5)
+ return EM # 6)
+
+
+#####################################################################
+# Public Key Cryptography related stuff
+#####################################################################
+
+class _EncryptAndVerify:
+ ### Below are encryption methods
+
+ def _rsaep(self, m):
+ """
+ Internal method providing raw RSA encryption, i.e. simple modular
+ exponentiation of the given message representative 'm', a long
+ between 0 and n-1.
+
+ This is the encryption primitive RSAEP described in PKCS#1 v2.1,
+ i.e. RFC 3447 Sect. 5.1.1.
+
+ Input:
+ m: message representative, a long between 0 and n-1, where
+ n is the key modulus.
+
+ Output:
+ ciphertext representative, a long between 0 and n-1
+
+ Not intended to be used directly. Please, see encrypt() method.
+ """
+
+ n = self.modulus
+ if type(m) is int:
+ m = long(m)
+ if type(m) is not long or m > n-1:
+ warning("Key._rsaep() expects a long between 0 and n-1")
+ return None
+
+ return self.key.encrypt(m, "")[0]
+
+
+ def _rsaes_pkcs1_v1_5_encrypt(self, M):
+ """
+ Implements RSAES-PKCS1-V1_5-ENCRYPT() function described in section
+ 7.2.1 of RFC 3447.
+
+ Input:
+ M: message to be encrypted, an octet string of length mLen, where
+ mLen <= k - 11 (k denotes the length in octets of the key modulus)
+
+ Output:
+ ciphertext, an octet string of length k
+
+ On error, None is returned.
+ """
+
+ # 1) Length checking
+ mLen = len(M)
+ k = self.modulusLen / 8
+ if mLen > k - 11:
+ warning("Key._rsaes_pkcs1_v1_5_encrypt(): message too "
+ "long (%d > %d - 11)" % (mLen, k))
+ return None
+
+ # 2) EME-PKCS1-v1_5 encoding
+ PS = zerofree_randstring(k - mLen - 3) # 2.a)
+ EM = '\x00' + '\x02' + PS + '\x00' + M # 2.b)
+
+ # 3) RSA encryption
+ m = pkcs_os2ip(EM) # 3.a)
+ c = self._rsaep(m) # 3.b)
+ C = pkcs_i2osp(c, k) # 3.c)
+
+ return C # 4)
+
+
+ def _rsaes_oaep_encrypt(self, M, h=None, mgf=None, L=None):
+ """
+ Internal method providing RSAES-OAEP-ENCRYPT as defined in Sect.
+ 7.1.1 of RFC 3447. Not intended to be used directly. Please, see
+ encrypt() method for type "OAEP".
+
+
+ Input:
+ M : message to be encrypted, an octet string of length mLen
+ where mLen <= k - 2*hLen - 2 (k denotes the length in octets
+ of the RSA modulus and hLen the length in octets of the hash
+ function output)
+ h : hash function name (in 'md2', 'md4', 'md5', 'sha1', 'tls',
+ 'sha256', 'sha384'). hLen denotes the length in octets of
+ the hash function output. 'sha1' is used by default if not
+ provided.
+ mgf: the mask generation function f : seed, maskLen -> mask
+ L : optional label to be associated with the message; the default
+ value for L, if not provided is the empty string
+
+ Output:
+ ciphertext, an octet string of length k
+
+ On error, None is returned.
+ """
+ # The steps below are the one described in Sect. 7.1.1 of RFC 3447.
+ # 1) Length Checking
+ # 1.a) is not done
+ mLen = len(M)
+ if h is None:
+ h = "sha1"
+ if not _hashFuncParams.has_key(h):
+ warning("Key._rsaes_oaep_encrypt(): unknown hash function %s.", h)
+ return None
+ hLen = _hashFuncParams[h][0]
+ hFun = _hashFuncParams[h][1]
+ k = self.modulusLen / 8
+ if mLen > k - 2*hLen - 2: # 1.b)
+ warning("Key._rsaes_oaep_encrypt(): message too long.")
+ return None
+
+ # 2) EME-OAEP encoding
+ if L is None: # 2.a)
+ L = ""
+ lHash = hFun(L)
+ PS = '\x00'*(k - mLen - 2*hLen - 2) # 2.b)
+ DB = lHash + PS + '\x01' + M # 2.c)
+ seed = randstring(hLen) # 2.d)
+ if mgf is None: # 2.e)
+ mgf = lambda x,y: pkcs_mgf1(x,y,h)
+ dbMask = mgf(seed, k - hLen - 1)
+ maskedDB = strxor(DB, dbMask) # 2.f)
+ seedMask = mgf(maskedDB, hLen) # 2.g)
+ maskedSeed = strxor(seed, seedMask) # 2.h)
+ EM = '\x00' + maskedSeed + maskedDB # 2.i)
+
+ # 3) RSA Encryption
+ m = pkcs_os2ip(EM) # 3.a)
+ c = self._rsaep(m) # 3.b)
+ C = pkcs_i2osp(c, k) # 3.c)
+
+ return C # 4)
+
+
+ def encrypt(self, m, t=None, h=None, mgf=None, L=None):
+ """
+ Encrypt message 'm' using 't' encryption scheme where 't' can be:
+
+ - None: the message 'm' is directly applied the RSAEP encryption
+ primitive, as described in PKCS#1 v2.1, i.e. RFC 3447
+ Sect 5.1.1. Simply put, the message undergo a modular
+ exponentiation using the public key. Additionnal method
+ parameters are just ignored.
+
+ - 'pkcs': the message 'm' is applied RSAES-PKCS1-V1_5-ENCRYPT encryption
+ scheme as described in section 7.2.1 of RFC 3447. In that
+ context, other parameters ('h', 'mgf', 'l') are not used.
+
+ - 'oaep': the message 'm' is applied the RSAES-OAEP-ENCRYPT encryption
+ scheme, as described in PKCS#1 v2.1, i.e. RFC 3447 Sect
+ 7.1.1. In that context,
+
+ o 'h' parameter provides the name of the hash method to use.
+ Possible values are "md2", "md4", "md5", "sha1", "tls",
+ "sha224", "sha256", "sha384" and "sha512". if none is provided,
+ sha1 is used.
+
+ o 'mgf' is the mask generation function. By default, mgf
+ is derived from the provided hash function using the
+ generic MGF1 (see pkcs_mgf1() for details).
+
+ o 'L' is the optional label to be associated with the
+ message. If not provided, the default value is used, i.e
+ the empty string. No check is done on the input limitation
+ of the hash function regarding the size of 'L' (for
+ instance, 2^61 - 1 for SHA-1). You have been warned.
+ """
+
+ if t is None: # Raw encryption
+ m = pkcs_os2ip(m)
+ c = self._rsaep(m)
+ return pkcs_i2osp(c, self.modulusLen/8)
+
+ elif t == "pkcs":
+ return self._rsaes_pkcs1_v1_5_encrypt(m)
+
+ elif t == "oaep":
+ return self._rsaes_oaep_encrypt(m, h, mgf, L)
+
+ else:
+ warning("Key.encrypt(): Unknown encryption type (%s) provided" % t)
+ return None
+
+ ### Below are verification related methods
+
+ def _rsavp1(self, s):
+ """
+ Internal method providing raw RSA verification, i.e. simple modular
+ exponentiation of the given signature representative 'c', an integer
+ between 0 and n-1.
+
+ This is the signature verification primitive RSAVP1 described in
+ PKCS#1 v2.1, i.e. RFC 3447 Sect. 5.2.2.
+
+ Input:
+ s: signature representative, an integer between 0 and n-1,
+ where n is the key modulus.
+
+ Output:
+ message representative, an integer between 0 and n-1
+
+ Not intended to be used directly. Please, see verify() method.
+ """
+ return self._rsaep(s)
+
+ def _rsassa_pss_verify(self, M, S, h=None, mgf=None, sLen=None):
+ """
+ Implements RSASSA-PSS-VERIFY() function described in Sect 8.1.2
+ of RFC 3447
+
+ Input:
+ M: message whose signature is to be verified
+ S: signature to be verified, an octet string of length k, where k
+ is the length in octets of the RSA modulus n.
+
+ Output:
+ True is the signature is valid. False otherwise.
+ """
+
+ # Set default parameters if not provided
+ if h is None: # By default, sha1
+ h = "sha1"
+ if not _hashFuncParams.has_key(h):
+ warning("Key._rsassa_pss_verify(): unknown hash function "
+ "provided (%s)" % h)
+ return False
+ if mgf is None: # use mgf1 with underlying hash function
+ mgf = lambda x,y: pkcs_mgf1(x, y, h)
+ if sLen is None: # use Hash output length (A.2.3 of RFC 3447)
+ hLen = _hashFuncParams[h][0]
+ sLen = hLen
+
+ # 1) Length checking
+ modBits = self.modulusLen
+ k = modBits / 8
+ if len(S) != k:
+ return False
+
+ # 2) RSA verification
+ s = pkcs_os2ip(S) # 2.a)
+ m = self._rsavp1(s) # 2.b)
+ emLen = math.ceil((modBits - 1) / 8.) # 2.c)
+ EM = pkcs_i2osp(m, emLen)
+
+ # 3) EMSA-PSS verification
+ Result = pkcs_emsa_pss_verify(M, EM, modBits - 1, h, mgf, sLen)
+
+ return Result # 4)
+
+
+ def _rsassa_pkcs1_v1_5_verify(self, M, S, h):
+ """
+ Implements RSASSA-PKCS1-v1_5-VERIFY() function as described in
+ Sect. 8.2.2 of RFC 3447.
+
+ Input:
+ M: message whose signature is to be verified, an octet string
+ S: signature to be verified, an octet string of length k, where
+ k is the length in octets of the RSA modulus n
+ h: hash function name (in 'md2', 'md4', 'md5', 'sha1', 'tls',
+ 'sha256', 'sha384').
+
+ Output:
+ True if the signature is valid. False otherwise.
+ """
+
+ # 1) Length checking
+ k = self.modulusLen / 8
+ if len(S) != k:
+ warning("invalid signature (len(S) != k)")
+ return False
+
+ # 2) RSA verification
+ s = pkcs_os2ip(S) # 2.a)
+ m = self._rsavp1(s) # 2.b)
+ EM = pkcs_i2osp(m, k) # 2.c)
+
+ # 3) EMSA-PKCS1-v1_5 encoding
+ EMPrime = pkcs_emsa_pkcs1_v1_5_encode(M, k, h)
+ if EMPrime is None:
+ warning("Key._rsassa_pkcs1_v1_5_verify(): unable to encode.")
+ return False
+
+ # 4) Comparison
+ return EM == EMPrime
+
+
+ def verify(self, M, S, t=None, h=None, mgf=None, sLen=None):
+ """
+ Verify alleged signature 'S' is indeed the signature of message 'M' using
+ 't' signature scheme where 't' can be:
+
+ - None: the alleged signature 'S' is directly applied the RSAVP1 signature
+ primitive, as described in PKCS#1 v2.1, i.e. RFC 3447 Sect
+ 5.2.1. Simply put, the provided signature is applied a moular
+ exponentiation using the public key. Then, a comparison of the
+ result is done against 'M'. On match, True is returned.
+ Additionnal method parameters are just ignored.
+
+ - 'pkcs': the alleged signature 'S' and message 'M' are applied
+ RSASSA-PKCS1-v1_5-VERIFY signature verification scheme as
+ described in Sect. 8.2.2 of RFC 3447. In that context,
+ the hash function name is passed using 'h'. Possible values are
+ "md2", "md4", "md5", "sha1", "tls", "sha224", "sha256", "sha384"
+ and "sha512". If none is provided, sha1 is used. Other additionnal
+ parameters are ignored.
+
+ - 'pss': the alleged signature 'S' and message 'M' are applied
+ RSASSA-PSS-VERIFY signature scheme as described in Sect. 8.1.2.
+ of RFC 3447. In that context,
+
+ o 'h' parameter provides the name of the hash method to use.
+ Possible values are "md2", "md4", "md5", "sha1", "tls", "sha224",
+ "sha256", "sha384" and "sha512". if none is provided, sha1
+ is used.
+
+ o 'mgf' is the mask generation function. By default, mgf
+ is derived from the provided hash function using the
+ generic MGF1 (see pkcs_mgf1() for details).
+
+ o 'sLen' is the length in octet of the salt. You can overload the
+ default value (the octet length of the hash value for provided
+ algorithm) by providing another one with that parameter.
+ """
+ if t is None: # RSAVP1
+ S = pkcs_os2ip(S)
+ n = self.modulus
+ if S > n-1:
+ warning("Signature to be verified is too long for key modulus")
+ return False
+ m = self._rsavp1(S)
+ if m is None:
+ return False
+ l = int(math.ceil(math.log(m, 2) / 8.)) # Hack
+ m = pkcs_i2osp(m, l)
+ return M == m
+
+ elif t == "pkcs": # RSASSA-PKCS1-v1_5-VERIFY
+ if h is None:
+ h = "sha1"
+ return self._rsassa_pkcs1_v1_5_verify(M, S, h)
+
+ elif t == "pss": # RSASSA-PSS-VERIFY
+ return self._rsassa_pss_verify(M, S, h, mgf, sLen)
+
+ else:
+ warning("Key.verify(): Unknown signature type (%s) provided" % t)
+ return None
+
+class _DecryptAndSignMethods:
+ ### Below are decryption related methods. Encryption ones are inherited
+ ### from PubKey
+
+ def _rsadp(self, c):
+ """
+ Internal method providing raw RSA decryption, i.e. simple modular
+ exponentiation of the given ciphertext representative 'c', a long
+ between 0 and n-1.
+
+ This is the decryption primitive RSADP described in PKCS#1 v2.1,
+ i.e. RFC 3447 Sect. 5.1.2.
+
+ Input:
+ c: ciphertest representative, a long between 0 and n-1, where
+ n is the key modulus.
+
+ Output:
+ ciphertext representative, a long between 0 and n-1
+
+ Not intended to be used directly. Please, see encrypt() method.
+ """
+
+ n = self.modulus
+ if type(c) is int:
+ c = long(c)
+ if type(c) is not long or c > n-1:
+ warning("Key._rsaep() expects a long between 0 and n-1")
+ return None
+
+ return self.key.decrypt(c)
+
+
+ def _rsaes_pkcs1_v1_5_decrypt(self, C):
+ """
+ Implements RSAES-PKCS1-V1_5-DECRYPT() function described in section
+ 7.2.2 of RFC 3447.
+
+ Input:
+ C: ciphertext to be decrypted, an octet string of length k, where
+ k is the length in octets of the RSA modulus n.
+
+ Output:
+ an octet string of length k at most k - 11
+
+ on error, None is returned.
+ """
+
+ # 1) Length checking
+ cLen = len(C)
+ k = self.modulusLen / 8
+ if cLen != k or k < 11:
+ warning("Key._rsaes_pkcs1_v1_5_decrypt() decryption error "
+ "(cLen != k or k < 11)")
+ return None
+
+ # 2) RSA decryption
+ c = pkcs_os2ip(C) # 2.a)
+ m = self._rsadp(c) # 2.b)
+ EM = pkcs_i2osp(m, k) # 2.c)
+
+ # 3) EME-PKCS1-v1_5 decoding
+
+ # I am aware of the note at the end of 7.2.2 regarding error
+ # conditions reporting but the one provided below are for _local_
+ # debugging purposes. --arno
+
+ if EM[0] != '\x00':
+ warning("Key._rsaes_pkcs1_v1_5_decrypt(): decryption error "
+ "(first byte is not 0x00)")
+ return None
+
+ if EM[1] != '\x02':
+ warning("Key._rsaes_pkcs1_v1_5_decrypt(): decryption error "
+ "(second byte is not 0x02)")
+ return None
+
+ tmp = EM[2:].split('\x00', 1)
+ if len(tmp) != 2:
+ warning("Key._rsaes_pkcs1_v1_5_decrypt(): decryption error "
+ "(no 0x00 to separate PS from M)")
+ return None
+
+ PS, M = tmp
+ if len(PS) < 8:
+ warning("Key._rsaes_pkcs1_v1_5_decrypt(): decryption error "
+ "(PS is less than 8 byte long)")
+ return None
+
+ return M # 4)
+
+
+ def _rsaes_oaep_decrypt(self, C, h=None, mgf=None, L=None):
+ """
+ Internal method providing RSAES-OAEP-DECRYPT as defined in Sect.
+ 7.1.2 of RFC 3447. Not intended to be used directly. Please, see
+ encrypt() method for type "OAEP".
+
+
+ Input:
+ C : ciphertext to be decrypted, an octet string of length k, where
+ k = 2*hLen + 2 (k denotes the length in octets of the RSA modulus
+ and hLen the length in octets of the hash function output)
+ h : hash function name (in 'md2', 'md4', 'md5', 'sha1', 'tls',
+ 'sha256', 'sha384'). 'sha1' is used if none is provided.
+ mgf: the mask generation function f : seed, maskLen -> mask
+ L : optional label whose association with the message is to be
+ verified; the default value for L, if not provided is the empty
+ string.
+
+ Output:
+ message, an octet string of length k mLen, where mLen <= k - 2*hLen - 2
+
+ On error, None is returned.
+ """
+ # The steps below are the one described in Sect. 7.1.2 of RFC 3447.
+
+ # 1) Length Checking
+ # 1.a) is not done
+ if h is None:
+ h = "sha1"
+ if not _hashFuncParams.has_key(h):
+ warning("Key._rsaes_oaep_decrypt(): unknown hash function %s.", h)
+ return None
+ hLen = _hashFuncParams[h][0]
+ hFun = _hashFuncParams[h][1]
+ k = self.modulusLen / 8
+ cLen = len(C)
+ if cLen != k: # 1.b)
+ warning("Key._rsaes_oaep_decrypt(): decryption error. "
+ "(cLen != k)")
+ return None
+ if k < 2*hLen + 2:
+ warning("Key._rsaes_oaep_decrypt(): decryption error. "
+ "(k < 2*hLen + 2)")
+ return None
+
+ # 2) RSA decryption
+ c = pkcs_os2ip(C) # 2.a)
+ m = self._rsadp(c) # 2.b)
+ EM = pkcs_i2osp(m, k) # 2.c)
+
+ # 3) EME-OAEP decoding
+ if L is None: # 3.a)
+ L = ""
+ lHash = hFun(L)
+ Y = EM[:1] # 3.b)
+ if Y != '\x00':
+ warning("Key._rsaes_oaep_decrypt(): decryption error. "
+ "(Y is not zero)")
+ return None
+ maskedSeed = EM[1:1+hLen]
+ maskedDB = EM[1+hLen:]
+ if mgf is None:
+ mgf = lambda x,y: pkcs_mgf1(x, y, h)
+ seedMask = mgf(maskedDB, hLen) # 3.c)
+ seed = strxor(maskedSeed, seedMask) # 3.d)
+ dbMask = mgf(seed, k - hLen - 1) # 3.e)
+ DB = strxor(maskedDB, dbMask) # 3.f)
+
+ # I am aware of the note at the end of 7.1.2 regarding error
+ # conditions reporting but the one provided below are for _local_
+ # debugging purposes. --arno
+
+ lHashPrime = DB[:hLen] # 3.g)
+ tmp = DB[hLen:].split('\x01', 1)
+ if len(tmp) != 2:
+ warning("Key._rsaes_oaep_decrypt(): decryption error. "
+ "(0x01 separator not found)")
+ return None
+ PS, M = tmp
+ if PS != '\x00'*len(PS):
+ warning("Key._rsaes_oaep_decrypt(): decryption error. "
+ "(invalid padding string)")
+ return None
+ if lHash != lHashPrime:
+ warning("Key._rsaes_oaep_decrypt(): decryption error. "
+ "(invalid hash)")
+ return None
+ return M # 4)
+
+
+ def decrypt(self, C, t=None, h=None, mgf=None, L=None):
+ """
+ Decrypt ciphertext 'C' using 't' decryption scheme where 't' can be:
+
+ - None: the ciphertext 'C' is directly applied the RSADP decryption
+ primitive, as described in PKCS#1 v2.1, i.e. RFC 3447
+ Sect 5.1.2. Simply, put the message undergo a modular
+ exponentiation using the private key. Additionnal method
+ parameters are just ignored.
+
+ - 'pkcs': the ciphertext 'C' is applied RSAES-PKCS1-V1_5-DECRYPT
+ decryption scheme as described in section 7.2.2 of RFC 3447.
+ In that context, other parameters ('h', 'mgf', 'l') are not
+ used.
+
+ - 'oaep': the ciphertext 'C' is applied the RSAES-OAEP-DECRYPT decryption
+ scheme, as described in PKCS#1 v2.1, i.e. RFC 3447 Sect
+ 7.1.2. In that context,
+
+ o 'h' parameter provides the name of the hash method to use.
+ Possible values are "md2", "md4", "md5", "sha1", "tls",
+ "sha224", "sha256", "sha384" and "sha512". if none is provided,
+ sha1 is used by default.
+
+ o 'mgf' is the mask generation function. By default, mgf
+ is derived from the provided hash function using the
+ generic MGF1 (see pkcs_mgf1() for details).
+
+ o 'L' is the optional label to be associated with the
+ message. If not provided, the default value is used, i.e
+ the empty string. No check is done on the input limitation
+ of the hash function regarding the size of 'L' (for
+ instance, 2^61 - 1 for SHA-1). You have been warned.
+ """
+ if t is None:
+ C = pkcs_os2ip(C)
+ c = self._rsadp(C)
+ l = int(math.ceil(math.log(c, 2) / 8.)) # Hack
+ return pkcs_i2osp(c, l)
+
+ elif t == "pkcs":
+ return self._rsaes_pkcs1_v1_5_decrypt(C)
+
+ elif t == "oaep":
+ return self._rsaes_oaep_decrypt(C, h, mgf, L)
+
+ else:
+ warning("Key.decrypt(): Unknown decryption type (%s) provided" % t)
+ return None
+
+ ### Below are signature related methods. Verification ones are inherited from
+ ### PubKey
+
+ def _rsasp1(self, m):
+ """
+ Internal method providing raw RSA signature, i.e. simple modular
+ exponentiation of the given message representative 'm', an integer
+ between 0 and n-1.
+
+ This is the signature primitive RSASP1 described in PKCS#1 v2.1,
+ i.e. RFC 3447 Sect. 5.2.1.
+
+ Input:
+ m: message representative, an integer between 0 and n-1, where
+ n is the key modulus.
+
+ Output:
+ signature representative, an integer between 0 and n-1
+
+ Not intended to be used directly. Please, see sign() method.
+ """
+ return self._rsadp(m)
+
+
+ def _rsassa_pss_sign(self, M, h=None, mgf=None, sLen=None):
+ """
+ Implements RSASSA-PSS-SIGN() function described in Sect. 8.1.1 of
+ RFC 3447.
+
+ Input:
+ M: message to be signed, an octet string
+
+ Output:
+ signature, an octet string of length k, where k is the length in
+ octets of the RSA modulus n.
+
+ On error, None is returned.
+ """
+
+ # Set default parameters if not provided
+ if h is None: # By default, sha1
+ h = "sha1"
+ if not _hashFuncParams.has_key(h):
+ warning("Key._rsassa_pss_sign(): unknown hash function "
+ "provided (%s)" % h)
+ return None
+ if mgf is None: # use mgf1 with underlying hash function
+ mgf = lambda x,y: pkcs_mgf1(x, y, h)
+ if sLen is None: # use Hash output length (A.2.3 of RFC 3447)
+ hLen = _hashFuncParams[h][0]
+ sLen = hLen
+
+ # 1) EMSA-PSS encoding
+ modBits = self.modulusLen
+ k = modBits / 8
+ EM = pkcs_emsa_pss_encode(M, modBits - 1, h, mgf, sLen)
+ if EM is None:
+ warning("Key._rsassa_pss_sign(): unable to encode")
+ return None
+
+ # 2) RSA signature
+ m = pkcs_os2ip(EM) # 2.a)
+ s = self._rsasp1(m) # 2.b)
+ S = pkcs_i2osp(s, k) # 2.c)
+
+ return S # 3)
+
+
+ def _rsassa_pkcs1_v1_5_sign(self, M, h):
+ """
+ Implements RSASSA-PKCS1-v1_5-SIGN() function as described in
+ Sect. 8.2.1 of RFC 3447.
+
+ Input:
+ M: message to be signed, an octet string
+ h: hash function name (in 'md2', 'md4', 'md5', 'sha1', 'tls'
+ 'sha256', 'sha384').
+
+ Output:
+ the signature, an octet string.
+ """
+
+ # 1) EMSA-PKCS1-v1_5 encoding
+ k = self.modulusLen / 8
+ EM = pkcs_emsa_pkcs1_v1_5_encode(M, k, h)
+ if EM is None:
+ warning("Key._rsassa_pkcs1_v1_5_sign(): unable to encode")
+ return None
+
+ # 2) RSA signature
+ m = pkcs_os2ip(EM) # 2.a)
+ s = self._rsasp1(m) # 2.b)
+ S = pkcs_i2osp(s, k) # 2.c)
+
+ return S # 3)
+
+
+ def sign(self, M, t=None, h=None, mgf=None, sLen=None):
+ """
+ Sign message 'M' using 't' signature scheme where 't' can be:
+
+ - None: the message 'M' is directly applied the RSASP1 signature
+ primitive, as described in PKCS#1 v2.1, i.e. RFC 3447 Sect
+ 5.2.1. Simply put, the message undergo a modular exponentiation
+ using the private key. Additionnal method parameters are just
+ ignored.
+
+ - 'pkcs': the message 'M' is applied RSASSA-PKCS1-v1_5-SIGN signature
+ scheme as described in Sect. 8.2.1 of RFC 3447. In that context,
+ the hash function name is passed using 'h'. Possible values are
+ "md2", "md4", "md5", "sha1", "tls", "sha224", "sha256", "sha384"
+ and "sha512". If none is provided, sha1 is used. Other additionnal
+ parameters are ignored.
+
+ - 'pss' : the message 'M' is applied RSASSA-PSS-SIGN signature scheme as
+ described in Sect. 8.1.1. of RFC 3447. In that context,
+
+ o 'h' parameter provides the name of the hash method to use.
+ Possible values are "md2", "md4", "md5", "sha1", "tls", "sha224",
+ "sha256", "sha384" and "sha512". if none is provided, sha1
+ is used.
+
+ o 'mgf' is the mask generation function. By default, mgf
+ is derived from the provided hash function using the
+ generic MGF1 (see pkcs_mgf1() for details).
+
+ o 'sLen' is the length in octet of the salt. You can overload the
+ default value (the octet length of the hash value for provided
+ algorithm) by providing another one with that parameter.
+ """
+
+ if t is None: # RSASP1
+ M = pkcs_os2ip(M)
+ n = self.modulus
+ if M > n-1:
+ warning("Message to be signed is too long for key modulus")
+ return None
+ s = self._rsasp1(M)
+ if s is None:
+ return None
+ return pkcs_i2osp(s, self.modulusLen/8)
+
+ elif t == "pkcs": # RSASSA-PKCS1-v1_5-SIGN
+ if h is None:
+ h = "sha1"
+ return self._rsassa_pkcs1_v1_5_sign(M, h)
+
+ elif t == "pss": # RSASSA-PSS-SIGN
+ return self._rsassa_pss_sign(M, h, mgf, sLen)
+
+ else:
+ warning("Key.sign(): Unknown signature type (%s) provided" % t)
+ return None
+
+class Key(_DecryptAndSignMethods, _EncryptAndVerify):
+
+ def __init__(self, pem_data):
+ self.key = RSA.importKey(pem_data)
+ self.modulus = self.key.key.n
+ self.modulusLen = self.key.key.size() + 1
+ self.privExp = self.key.key.d
+ self.pubExp = self.key.key.e
+ self.prime1 = self.key.key.p
+ self.prime2 = self.key.key.q
+ self.exponent1 = 0
+ self.exponent2 = 0
+ self.coefficient = self.key.key.u