Add a test utility functions to read & process NIST vector files
diff --git a/tests/primitives/vectors/NIST/AES/KAT/CBCGFSbox256.rsp b/tests/primitives/vectors/NIST/AES/KAT/CBCGFSbox256.rsp
new file mode 100755
index 0000000..ad81143
--- /dev/null
+++ b/tests/primitives/vectors/NIST/AES/KAT/CBCGFSbox256.rsp
@@ -0,0 +1,71 @@
+# CAVS 11.1
+# Config info for aes_values
+# AESVS GFSbox test data for CBC
+# State : Encrypt and Decrypt
+# Key Length : 256
+# Generated on Fri Apr 22 15:11:38 2011
+
+[ENCRYPT]
+
+COUNT = 0
+KEY = 0000000000000000000000000000000000000000000000000000000000000000
+IV = 00000000000000000000000000000000
+PLAINTEXT = 014730f80ac625fe84f026c60bfd547d
+CIPHERTEXT = 5c9d844ed46f9885085e5d6a4f94c7d7
+
+COUNT = 1
+KEY = 0000000000000000000000000000000000000000000000000000000000000000
+IV = 00000000000000000000000000000000
+PLAINTEXT = 0b24af36193ce4665f2825d7b4749c98
+CIPHERTEXT = a9ff75bd7cf6613d3731c77c3b6d0c04
+
+COUNT = 2
+KEY = 0000000000000000000000000000000000000000000000000000000000000000
+IV = 00000000000000000000000000000000
+PLAINTEXT = 761c1fe41a18acf20d241650611d90f1
+CIPHERTEXT = 623a52fcea5d443e48d9181ab32c7421
+
+COUNT = 3
+KEY = 0000000000000000000000000000000000000000000000000000000000000000
+IV = 00000000000000000000000000000000
+PLAINTEXT = 8a560769d605868ad80d819bdba03771
+CIPHERTEXT = 38f2c7ae10612415d27ca190d27da8b4
+
+COUNT = 4
+KEY = 0000000000000000000000000000000000000000000000000000000000000000
+IV = 00000000000000000000000000000000
+PLAINTEXT = 91fbef2d15a97816060bee1feaa49afe
+CIPHERTEXT = 1bc704f1bce135ceb810341b216d7abe
+
+[DECRYPT]
+
+COUNT = 0
+KEY = 0000000000000000000000000000000000000000000000000000000000000000
+IV = 00000000000000000000000000000000
+CIPHERTEXT = 5c9d844ed46f9885085e5d6a4f94c7d7
+PLAINTEXT = 014730f80ac625fe84f026c60bfd547d
+
+COUNT = 1
+KEY = 0000000000000000000000000000000000000000000000000000000000000000
+IV = 00000000000000000000000000000000
+CIPHERTEXT = a9ff75bd7cf6613d3731c77c3b6d0c04
+PLAINTEXT = 0b24af36193ce4665f2825d7b4749c98
+
+COUNT = 2
+KEY = 0000000000000000000000000000000000000000000000000000000000000000
+IV = 00000000000000000000000000000000
+CIPHERTEXT = 623a52fcea5d443e48d9181ab32c7421
+PLAINTEXT = 761c1fe41a18acf20d241650611d90f1
+
+COUNT = 3
+KEY = 0000000000000000000000000000000000000000000000000000000000000000
+IV = 00000000000000000000000000000000
+CIPHERTEXT = 38f2c7ae10612415d27ca190d27da8b4
+PLAINTEXT = 8a560769d605868ad80d819bdba03771
+
+COUNT = 4
+KEY = 0000000000000000000000000000000000000000000000000000000000000000
+IV = 00000000000000000000000000000000
+CIPHERTEXT = 1bc704f1bce135ceb810341b216d7abe
+PLAINTEXT = 91fbef2d15a97816060bee1feaa49afe
+
diff --git a/tests/test_utils.py b/tests/test_utils.py
new file mode 100644
index 0000000..acb36d4
--- /dev/null
+++ b/tests/test_utils.py
@@ -0,0 +1,193 @@
+import textwrap
+
+from .utils import load_nist_vectors, load_nist_vectors_from_file
+
+
+def test_load_nist_vectors_encrypt():
+    vector_data = textwrap.dedent("""
+    # CAVS 11.1
+    # Config info for aes_values
+    # AESVS GFSbox test data for CBC
+    # State : Encrypt and Decrypt
+    # Key Length : 128
+    # Generated on Fri Apr 22 15:11:33 2011
+
+    [ENCRYPT]
+
+    COUNT = 0
+    KEY = 00000000000000000000000000000000
+    IV = 00000000000000000000000000000000
+    PLAINTEXT = f34481ec3cc627bacd5dc3fb08f273e6
+    CIPHERTEXT = 0336763e966d92595a567cc9ce537f5e
+
+    COUNT = 1
+    KEY = 00000000000000000000000000000000
+    IV = 00000000000000000000000000000000
+    PLAINTEXT = 9798c4640bad75c7c3227db910174e72
+    CIPHERTEXT = a9a1631bf4996954ebc093957b234589
+
+    [DECRYPT]
+
+    COUNT = 0
+    KEY = 00000000000000000000000000000000
+    IV = 00000000000000000000000000000000
+    CIPHERTEXT = 0336763e966d92595a567cc9ce537f5e
+    PLAINTEXT = f34481ec3cc627bacd5dc3fb08f273e6
+
+    COUNT = 1
+    KEY = 00000000000000000000000000000000
+    IV = 00000000000000000000000000000000
+    CIPHERTEXT = a9a1631bf4996954ebc093957b234589
+    PLAINTEXT = 9798c4640bad75c7c3227db910174e72
+    """).splitlines()
+
+    assert load_nist_vectors(vector_data, "ENCRYPT",
+        ["key", "iv", "plaintext", "ciphertext"],
+    ) == [
+        (
+            "00000000000000000000000000000000",
+            "00000000000000000000000000000000",
+            "f34481ec3cc627bacd5dc3fb08f273e6",
+            "0336763e966d92595a567cc9ce537f5e",
+        ),
+        (
+            "00000000000000000000000000000000",
+            "00000000000000000000000000000000",
+            "9798c4640bad75c7c3227db910174e72",
+            "a9a1631bf4996954ebc093957b234589",
+        ),
+    ]
+
+
+def test_load_nist_vectors_decrypt():
+    vector_data = textwrap.dedent("""
+    # CAVS 11.1
+    # Config info for aes_values
+    # AESVS GFSbox test data for CBC
+    # State : Encrypt and Decrypt
+    # Key Length : 128
+    # Generated on Fri Apr 22 15:11:33 2011
+
+    [ENCRYPT]
+
+    COUNT = 0
+    KEY = 00000000000000000000000000000000
+    IV = 00000000000000000000000000000000
+    PLAINTEXT = f34481ec3cc627bacd5dc3fb08f273e6
+    CIPHERTEXT = 0336763e966d92595a567cc9ce537f5e
+
+    COUNT = 1
+    KEY = 00000000000000000000000000000000
+    IV = 00000000000000000000000000000000
+    PLAINTEXT = 9798c4640bad75c7c3227db910174e72
+    CIPHERTEXT = a9a1631bf4996954ebc093957b234589
+
+    [DECRYPT]
+
+    COUNT = 0
+    KEY = 00000000000000000000000000000000
+    IV = 00000000000000000000000000000000
+    CIPHERTEXT = 0336763e966d92595a567cc9ce537f5e
+    PLAINTEXT = f34481ec3cc627bacd5dc3fb08f273e6
+
+    COUNT = 1
+    KEY = 00000000000000000000000000000000
+    IV = 00000000000000000000000000000000
+    CIPHERTEXT = a9a1631bf4996954ebc093957b234589
+    PLAINTEXT = 9798c4640bad75c7c3227db910174e72
+    """).splitlines()
+
+    assert load_nist_vectors(vector_data, "DECRYPT",
+        ["key", "iv", "ciphertext", "plaintext"],
+    ) == [
+        (
+            "00000000000000000000000000000000",
+            "00000000000000000000000000000000",
+            "0336763e966d92595a567cc9ce537f5e",
+            "f34481ec3cc627bacd5dc3fb08f273e6",
+        ),
+        (
+            "00000000000000000000000000000000",
+            "00000000000000000000000000000000",
+            "a9a1631bf4996954ebc093957b234589",
+            "9798c4640bad75c7c3227db910174e72",
+        ),
+    ]
+
+
+def test_load_nist_vectors_from_file_encrypt():
+    assert load_nist_vectors_from_file(
+        "AES/KAT/CBCGFSbox256.rsp",
+        "ENCRYPT",
+        ["key", "iv", "plaintext", "ciphertext"],
+    ) == [
+        (
+            "0000000000000000000000000000000000000000000000000000000000000000",
+            "00000000000000000000000000000000",
+            "014730f80ac625fe84f026c60bfd547d",
+            "5c9d844ed46f9885085e5d6a4f94c7d7",
+        ),
+        (
+            "0000000000000000000000000000000000000000000000000000000000000000",
+            "00000000000000000000000000000000",
+            "0b24af36193ce4665f2825d7b4749c98",
+            "a9ff75bd7cf6613d3731c77c3b6d0c04",
+        ),
+        (
+            "0000000000000000000000000000000000000000000000000000000000000000",
+            "00000000000000000000000000000000",
+            "761c1fe41a18acf20d241650611d90f1",
+            "623a52fcea5d443e48d9181ab32c7421",
+        ),
+        (
+            "0000000000000000000000000000000000000000000000000000000000000000",
+            "00000000000000000000000000000000",
+            "8a560769d605868ad80d819bdba03771",
+            "38f2c7ae10612415d27ca190d27da8b4",
+        ),
+        (
+            "0000000000000000000000000000000000000000000000000000000000000000",
+            "00000000000000000000000000000000",
+            "91fbef2d15a97816060bee1feaa49afe",
+            "1bc704f1bce135ceb810341b216d7abe",
+        ),
+    ]
+
+
+def test_load_nist_vectors_from_file_decypt():
+    assert load_nist_vectors_from_file(
+        "AES/KAT/CBCGFSbox256.rsp",
+        "DECRYPT",
+        ["key", "iv", "ciphertext", "plaintext"],
+    ) == [
+        (
+            "0000000000000000000000000000000000000000000000000000000000000000",
+            "00000000000000000000000000000000",
+            "5c9d844ed46f9885085e5d6a4f94c7d7",
+            "014730f80ac625fe84f026c60bfd547d",
+        ),
+        (
+            "0000000000000000000000000000000000000000000000000000000000000000",
+            "00000000000000000000000000000000",
+            "a9ff75bd7cf6613d3731c77c3b6d0c04",
+            "0b24af36193ce4665f2825d7b4749c98",
+        ),
+        (
+            "0000000000000000000000000000000000000000000000000000000000000000",
+            "00000000000000000000000000000000",
+            "623a52fcea5d443e48d9181ab32c7421",
+            "761c1fe41a18acf20d241650611d90f1",
+        ),
+        (
+            "0000000000000000000000000000000000000000000000000000000000000000",
+            "00000000000000000000000000000000",
+            "38f2c7ae10612415d27ca190d27da8b4",
+            "8a560769d605868ad80d819bdba03771",
+        ),
+        (
+            "0000000000000000000000000000000000000000000000000000000000000000",
+            "00000000000000000000000000000000",
+            "1bc704f1bce135ceb810341b216d7abe",
+            "91fbef2d15a97816060bee1feaa49afe",
+        ),
+    ]
diff --git a/tests/utils.py b/tests/utils.py
new file mode 100644
index 0000000..9fe3531
--- /dev/null
+++ b/tests/utils.py
@@ -0,0 +1,48 @@
+import os.path
+
+
+def load_nist_vectors(vector_data, op, fields):
+    section, count, data = None, None, {}
+
+    for line in vector_data:
+        line = line.strip()
+
+        # Blank lines are ignored
+        if not line:
+            continue
+
+        # Lines starting with # are comments
+        if line.startswith("#"):
+            continue
+
+        # Look for section headers
+        if line.startswith("[") and line.endswith("]"):
+            section = line[1:-1]
+            data[section] = {}
+            continue
+
+        # Build our data using a simple Key = Value format
+        name, value = line.split(" = ")
+
+        # COUNT is a special token that indicates a new block of data
+        if name.upper() == "COUNT":
+            count = value
+            data[section][count] = {}
+        # For all other tokens we simply want the name, value stored in
+        # the dictionary
+        else:
+            data[section][count][name.lower()] = value
+
+    # We want to test only for a particular operation
+    return [
+        tuple(vector[1][f] for f in fields)
+        for vector in sorted(data[op].items(), key=lambda v: v[0])
+    ]
+
+
+def load_nist_vectors_from_file(filename, op, fields):
+    base = os.path.join(
+        os.path.dirname(__file__), "primitives", "vectors", "NIST",
+    )
+    with open(os.path.join(base, filename), "r") as vector_file:
+        return load_nist_vectors(vector_file, op, fields)