Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Add signature_algorithms_cert extension to _serverTLS13Handshake #513

Open
wants to merge 4 commits into
base: master
Choose a base branch
from
Open

Add signature_algorithms_cert extension to _serverTLS13Handshake #513

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
d88c16b
Add signature_algorithms_cert extension to the "_serverTLS13Handshake…
Odinmylord Apr 9, 2024
207aa80
Fix names and update _sigHashesToList
Odinmylord Apr 11, 2024
bd28f87
Fix issues with linter
Odinmylord Apr 12, 2024
c2272ee
fix long lines
Odinmylord Apr 12, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
10 changes: 10 additions & 0 deletions tlslite/handshakesettings.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -396,6 +396,11 @@ def _init_misc_extensions(self):
# resumed connections (as tickets are single-use in TLS 1.3
self.ticket_count = 2
self.record_size_limit = 2**14 + 1 # TLS 1.3 includes content type
# data needed for the signature algorithms cert extension
self.more_sig_schemes_cert = list(SIGNATURE_SCHEMES)
self.ecdsa_sig_hashes_cert = list(ECDSA_SIGNATURE_HASHES)
self.rsa_sig_hashes_cert = list(RSA_SIGNATURE_HASHES)
self.rsa_sig_schemes_cert = list(RSA_SCHEMES)

def __init__(self):
"""Initialise default values for settings."""
Expand Down Expand Up @@ -675,6 +680,11 @@ def _copy_extension_settings(self, other):
other.max_early_data = self.max_early_data
other.ticket_count = self.ticket_count
other.record_size_limit = self.record_size_limit
# signature algorithms cert
other.more_sig_schemes_cert = self.more_sig_schemes_cert
other.ecdsa_sig_hashes_cert = self.ecdsa_sig_hashes_cert
other.rsa_sig_hashes_cert = self.rsa_sig_hashes_cert
other.rsa_sig_schemes_cert = self.rsa_sig_schemes_cert

@staticmethod
def _remove_all_matches(values, needle):
Expand Down
53 changes: 34 additions & 19 deletions tlslite/tlsconnection.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -2830,9 +2830,15 @@ def _serverTLS13Handshake(self, settings, clientHello, cipherSuite,
cr_settings.dsaSigHashes = []
valid_sig_algs = self._sigHashesToList(cr_settings)
assert valid_sig_algs

valid_sig_algs_cert = self._sigHashesToList(cr_settings,
sig_algs_cert=True)
certificate_request = CertificateRequest(self.version)
certificate_request.create(context=ctx, sig_algs=valid_sig_algs)
# if there is no difference the extension can be omitted
if set(valid_sig_algs_cert) != set(valid_sig_algs):
sig_algs_cert_ext = SignatureAlgorithmsCertExtension()
sig_algs_cert_ext.create(valid_sig_algs_cert)
certificate_request.addExtension(sig_algs_cert_ext)
self._queue_message(certificate_request)

certificate = Certificate(CertificateType.x509, self.version)
Expand Down Expand Up @@ -4668,7 +4674,7 @@ def _pickServerKeyExchangeSig(settings, clientHello, certList=None,

@staticmethod
def _sigHashesToList(settings, privateKey=None, certList=None,
version=(3, 3)):
version=(3, 3), sig_algs_cert=False):
"""Convert list of valid signature hashes to array of tuples"""
certType = None
publicKey = None
Expand All @@ -4679,7 +4685,9 @@ def _sigHashesToList(settings, privateKey=None, certList=None,
sigAlgs = []

if not certType or certType == "Ed25519" or certType == "Ed448":
for sig_scheme in settings.more_sig_schemes:
sig_schemes = settings.more_sig_schemes if not sig_algs_cert else \
settings.more_sig_schemes_cert
for sig_scheme in sig_schemes:
if version < (3, 3):
# EdDSA is supported only in TLS 1.2 and 1.3
continue
Expand All @@ -4688,60 +4696,67 @@ def _sigHashesToList(settings, privateKey=None, certList=None,
sigAlgs.append(getattr(SignatureScheme, sig_scheme.lower()))

if not certType or certType == "ecdsa":
for hashName in settings.ecdsaSigHashes:
hash_names = settings.ecdsaSigHashes if not sig_algs_cert else \
settings.ecdsa_sig_hashes_cert
for hash_name in hash_names:
# only SHA256, SHA384 and SHA512 are allowed in TLS 1.3
if version > (3, 3) and hashName in ("sha1", "sha224"):
if version > (3, 3) and hash_name in ("sha1", "sha224"):
continue

# in TLS 1.3 ECDSA key curve is bound to hash
if publicKey and version > (3, 3):
curve = publicKey.curve_name
matching_hash = TLSConnection._curve_name_to_hash_name(
curve)
if hashName != matching_hash:
if hash_name != matching_hash:
continue

sigAlgs.append((getattr(HashAlgorithm, hashName),
sigAlgs.append((getattr(HashAlgorithm, hash_name),
SignatureAlgorithm.ecdsa))

if not certType or certType == "dsa":
for hashName in settings.dsaSigHashes:
for hash_name in settings.dsaSigHashes:
if version > (3, 3):
continue

sigAlgs.append((getattr(HashAlgorithm, hashName),
sigAlgs.append((getattr(HashAlgorithm, hash_name),
SignatureAlgorithm.dsa))

if not certType or certType in ("rsa", "rsa-pss"):
for schemeName in settings.rsaSchemes:
rsa_schemes = settings.rsaSchemes if not sig_algs_cert else \
settings.rsa_sig_schemes_cert
for scheme_name in rsa_schemes:
# pkcs#1 v1.5 signatures are not allowed in TLS 1.3
if version > (3, 3) and schemeName == "pkcs1":
if version > (3, 3) and scheme_name == "pkcs1":
continue

for hashName in settings.rsaSigHashes:
rsa_sig_hashes = settings.rsaSigHashes if not sig_algs_cert else \
settings.rsa_sig_hashes_cert
for hash_name in rsa_sig_hashes:
# rsa-pss certificates can't be used to make PKCS#1 v1.5
# signatures
if certType == "rsa-pss" and schemeName == "pkcs1":
if certType == "rsa-pss" and scheme_name == "pkcs1":
continue
try:
# 1024 bit keys are too small to create valid
# rsa-pss-SHA512 signatures
if schemeName == 'pss' and hashName == 'sha512'\
if scheme_name == 'pss' and hash_name == 'sha512'\
and privateKey and privateKey.n < 2**2047:
continue
# advertise support for both rsaEncryption and RSA-PSS OID
# key type
if certType != 'rsa-pss':
sigAlgs.append(getattr(SignatureScheme,
"rsa_{0}_rsae_{1}"
.format(schemeName, hashName)))
.format(scheme_name,
hash_name)))
if certType != 'rsa':
sigAlgs.append(getattr(SignatureScheme,
"rsa_{0}_pss_{1}"
.format(schemeName, hashName)))
.format(scheme_name,
hash_name)))
except AttributeError:
if schemeName == 'pkcs1':
sigAlgs.append((getattr(HashAlgorithm, hashName),
if scheme_name == 'pkcs1':
sigAlgs.append((getattr(HashAlgorithm, hash_name),
SignatureAlgorithm.rsa))
continue
return sigAlgs
Expand Down
Loading