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authorPeter Maydell <peter.maydell@linaro.org>2020-08-31 19:39:12 +0100
committerPeter Maydell <peter.maydell@linaro.org>2020-08-31 19:39:13 +0100
commit2f4c51c0f384d7888a04b4815861e6d5fd244d75 (patch)
treed01ddd9e8821d9ab4f8a99c1e3b0fc3b92ff9691 /scripts/u2f-setup-gen.py
parent4bc08c61416cf9244175807b8752caf739f7681f (diff)
parentb946434f2659a182afc17e155be6791ebfb302eb (diff)
downloadfocaccia-qemu-2f4c51c0f384d7888a04b4815861e6d5fd244d75.tar.gz
focaccia-qemu-2f4c51c0f384d7888a04b4815861e6d5fd244d75.zip
Merge remote-tracking branch 'remotes/kraxel/tags/usb-20200831-pull-request' into staging
usb: usb_packet_map fixes for ehci and xhci.
usb: setup_len fix (CVE-2020-14364).
usb: u2f key support (GSoC).
 * v2: 32bit build fixed.
 * v3: libu2f-emu dependency fixed.

# gpg: Signature made Mon 31 Aug 2020 09:32:49 BST
# gpg:                using RSA key 4CB6D8EED3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>" [full]
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>" [full]
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>" [full]
# Primary key fingerprint: A032 8CFF B93A 17A7 9901  FE7D 4CB6 D8EE D3E8 7138

* remotes/kraxel/tags/usb-20200831-pull-request:
  usb: fix setup_len init (CVE-2020-14364)
  usb-host: workaround libusb bug
  hw/usb: Add U2F device autoscan to passthru mode
  hw/usb: Add U2F device check to passthru mode
  scripts: Add u2f-setup-gen script
  docs/qdev-device-use.txt: Add USB U2F key to the QDEV devices examples
  docs/system: Add U2F key to the USB devices examples
  meson: Add U2F key to meson
  hw/usb: Add U2F key emulated mode
  hw/usb: Add U2F key passthru mode
  hw/usb: Add U2F key base class implementation
  hw/usb: Add U2F key base class
  docs: Add USB U2F key device documentation
  hw/usb: Regroup USB HID protocol values
  ehci: drop pointless warn_report for guest bugs.
  hw: ehci: check return value of 'usb_packet_map'
  hw: ehci: destroy sglist in error path
  hw: xhci: check return value of 'usb_packet_map'

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'scripts/u2f-setup-gen.py')
-rwxr-xr-xscripts/u2f-setup-gen.py170
1 files changed, 170 insertions, 0 deletions
diff --git a/scripts/u2f-setup-gen.py b/scripts/u2f-setup-gen.py
new file mode 100755
index 0000000000..2122598fed
--- /dev/null
+++ b/scripts/u2f-setup-gen.py
@@ -0,0 +1,170 @@
+#!/usr/bin/env python3
+#
+# Libu2f-emu setup directory generator for USB U2F key emulation.
+#
+# Copyright (c) 2020 César Belley <cesar.belley@lse.epita.fr>
+# Written by César Belley <cesar.belley@lse.epita.fr>
+#
+# This work is licensed under the terms of the GNU GPL, version 2
+# or, at your option, any later version.  See the COPYING file in
+# the top-level directory.
+
+import sys
+import os
+from random import randint
+from typing import Tuple
+
+from cryptography.hazmat.backends import default_backend
+from cryptography.hazmat.primitives.asymmetric import ec
+from cryptography.hazmat.primitives.serialization import Encoding, \
+    NoEncryption, PrivateFormat, PublicFormat
+from OpenSSL import crypto
+
+
+def write_setup_dir(dirpath: str, privkey_pem: bytes, cert_pem: bytes,
+                    entropy: bytes, counter: int) -> None:
+    """
+    Write the setup directory.
+
+    Args:
+        dirpath: The directory path.
+        key_pem: The private key PEM.
+        cert_pem: The certificate PEM.
+        entropy: The 48 bytes of entropy.
+        counter: The counter value.
+    """
+    # Directory
+    os.mkdir(dirpath)
+
+    # Private key
+    with open(f'{dirpath}/private-key.pem', 'bw') as f:
+        f.write(privkey_pem)
+
+    # Certificate
+    with open(f'{dirpath}/certificate.pem', 'bw') as f:
+        f.write(cert_pem)
+
+    # Entropy
+    with open(f'{dirpath}/entropy', 'wb') as f:
+        f.write(entropy)
+
+    # Counter
+    with open(f'{dirpath}/counter', 'w') as f:
+        f.write(f'{str(counter)}\n')
+
+
+def generate_ec_key_pair() -> Tuple[str, str]:
+    """
+    Generate an ec key pair.
+
+    Returns:
+        The private and public key PEM.
+    """
+    # Key generation
+    privkey = ec.generate_private_key(ec.SECP256R1, default_backend())
+    pubkey = privkey.public_key()
+
+    # PEM serialization
+    privkey_pem = privkey.private_bytes(encoding=Encoding.PEM,
+                                        format=PrivateFormat.TraditionalOpenSSL,
+                                        encryption_algorithm=NoEncryption())
+    pubkey_pem = pubkey.public_bytes(encoding=Encoding.PEM,
+                                     format=PublicFormat.SubjectPublicKeyInfo)
+    return privkey_pem, pubkey_pem
+
+
+def generate_certificate(privkey_pem: str, pubkey_pem: str) -> str:
+    """
+    Generate a x509 certificate from a key pair.
+
+    Args:
+        privkey_pem: The private key PEM.
+        pubkey_pem: The public key PEM.
+
+    Returns:
+        The certificate PEM.
+    """
+    # Convert key pair
+    privkey = crypto.load_privatekey(crypto.FILETYPE_PEM, privkey_pem)
+    pubkey = crypto.load_publickey(crypto.FILETYPE_PEM, pubkey_pem)
+
+    # New x509v3 certificate
+    cert = crypto.X509()
+    cert.set_version(0x2)
+
+    # Serial number
+    cert.set_serial_number(randint(1, 2 ** 64))
+
+    # Before / After
+    cert.gmtime_adj_notBefore(0)
+    cert.gmtime_adj_notAfter(4 * (365 * 24 * 60 * 60))
+
+    # Public key
+    cert.set_pubkey(pubkey)
+
+    # Subject name and issueer
+    cert.get_subject().CN = "U2F emulated"
+    cert.set_issuer(cert.get_subject())
+
+    # Extensions
+    cert.add_extensions([
+        crypto.X509Extension(b"subjectKeyIdentifier",
+                             False, b"hash", subject=cert),
+    ])
+    cert.add_extensions([
+        crypto.X509Extension(b"authorityKeyIdentifier",
+                             False, b"keyid:always", issuer=cert),
+    ])
+    cert.add_extensions([
+        crypto.X509Extension(b"basicConstraints", True, b"CA:TRUE")
+    ])
+
+    # Signature
+    cert.sign(privkey, 'sha256')
+
+    return crypto.dump_certificate(crypto.FILETYPE_PEM, cert)
+
+
+def generate_setup_dir(dirpath: str) -> None:
+    """
+    Generates the setup directory.
+
+    Args:
+        dirpath: The directory path.
+    """
+    # Key pair
+    privkey_pem, pubkey_pem = generate_ec_key_pair()
+
+    # Certificate
+    certificate_pem = generate_certificate(privkey_pem, pubkey_pem)
+
+    # Entropy
+    entropy = os.urandom(48)
+
+    # Counter
+    counter = 0
+
+    # Write
+    write_setup_dir(dirpath, privkey_pem, certificate_pem, entropy, counter)
+
+
+def main() -> None:
+    """
+    Main function
+    """
+    # Dir path
+    if len(sys.argv) != 2:
+        sys.stderr.write(f'Usage: {sys.argv[0]} <setup_dir>\n')
+        exit(2)
+    dirpath = sys.argv[1]
+
+    # Dir non existence
+    if os.path.exists(dirpath):
+        sys.stderr.write(f'Directory: {dirpath} already exists.\n')
+        exit(1)
+
+    generate_setup_dir(dirpath)
+
+
+if __name__ == '__main__':
+    main()