First pass at RSA tests.

1 files changed, 86 insertions, 0 deletions

diff --git a/tests/test-rsa.py b/tests/test-rsa.py
new file mode 100644
index 0000000..759d5a3
--- /dev/null
+++ b/tests/test-rsa.py
@@ -0,0 +1,86 @@
+# Use PyCrypto to generate test data for Cryptech ModExp core.
+#
+# Funnily enough, PyCrypto and Cryptlib use exactly the same names for
+# RSA key components, see Cryptlib documentation pages 186-187 & 339.
+
+key_lengths = (1024, 2048, 4096)        # Lengths in bits of keys to generate
+pkcs_encoding = 8                       # PKCS encoding for PEM comment (1 or 8)
+
+plaintext = "You can hack anything you want with TECO and DDT."
+
+from Crypto                             import __version__ as PyCryptoVersion
+from Crypto.PublicKey                   import RSA
+from Crypto.Hash                        import SHA256
+from Crypto.Util.number                 import long_to_bytes
+from Crypto.Signature.PKCS1_v1_5        import EMSA_PKCS1_V1_5_ENCODE, PKCS115_SigScheme
+from textwrap                           import TextWrapper
+import sys, os.path
+
+assert all(key_length % 8 == 0 for key_length in key_lengths)
+
+scriptname = os.path.basename(sys.argv[0])
+
+wrapper = TextWrapper(width = 78, initial_indent = " " * 2, subsequent_indent = " " * 2)
+
+def printlines(*lines, **kwargs):
+  for line in lines:
+    sys.stdout.write(line % kwargs + "\n")
+
+def trailing_comma(item, sequence):
+  return "" if item == sequence[-1] else ","
+
+def print_hex(name, value, comment):
+  printlines("static const uint8_t %(name)s[] = { /* %(comment)s, %(length)d bytes */",
+             wrapper.fill(", ".join("0x%02x" % ord(v) for v in value)),
+             "};", "",
+             name = name, comment = comment, length  = len(value))
+
+h = SHA256.new(plaintext)
+
+printlines("/*",
+           " * RSA signature test data for Cryptech project, automatically generated by",
+           " * %(scriptname)s using PyCrypto version %(version)s. Do not edit.",
+           " *",
+           " * Plaintext: \"%(plaintext)s\"",
+           " * SHA-256: %(digest)s",
+           " */", "",
+           scriptname = scriptname,
+           version    = PyCryptoVersion,
+           plaintext  = plaintext,
+           digest     = h.hexdigest())
+
+for k_len in key_lengths:
+
+  k = RSA.generate(k_len)       # Cryptlib insists u < p, probably with good reason,
+  while k.u >= k.p:             # and I'm sure not going to argue the math with Peter,
+    k = RSA.generate(k_len)     # so keep trying until we pass this test
+
+  m = EMSA_PKCS1_V1_5_ENCODE(h, k_len/8)
+  s = PKCS115_SigScheme(k).sign(h)
+  assert len(m) == len(s)
+
+  printlines("/* %(k_len)d-bit RSA private key (PKCS #%(pkcs)d)",
+             k.exportKey(format = "PEM", pkcs = pkcs_encoding),
+             "*/", "",
+             k_len = k_len, pkcs  = pkcs_encoding)
+
+  for component in k.keydata:
+    print_hex("%s_%d" % (component, k_len),
+              long_to_bytes(getattr(k, component), blocksize = 4),
+              "key component %s" % component)
+  print_hex("m_%d" % k_len, m, "message to be signed")
+  print_hex("s_%d" % k_len, s, "signed message")
+
+fields = "nedpqums"
+printlines("typedef struct { const uint8_t *val; size_t len; } rsa_tc_bn_t;",
+           "typedef struct { size_t size; rsa_tc_bn_t %(fields)s; } rsa_tc_t;",
+           "",
+           "static const rsa_tc_t rsa_tc[] = {",
+           fields = ", ".join(fields))
+for k_len in key_lengths:
+  printlines("  { %(k_len)d,", k_len = k_len)
+  for field in fields:
+    printlines("    { %(field)s_%(k_len)d, sizeof(%(field)s_%(k_len)d) }%(comma)s",
+               field = field, k_len = k_len, comma = trailing_comma(field, fields))
+  printlines("  }%(comma)s", comma = trailing_comma(k_len, key_lengths))
+printlines("};")