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{
"cells": [
{
"cell_type": "code",
"execution_count": 12,
"id": "fedd7d1a-36a9-4255-8305-a720dfb7b500",
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"b\"{\\x8ea\\xf8wu!\\xeb\\xc4\\xc9\\xcb|\\\\\\xf1K\\xd5t\\x80i\\xbcD\\xb6!\\xfc\\xee\\x06lQ'V0\\xc6\"\n",
"7b8e61f8777521ebc4c9cb7c5cf14bd5748069bc44b621fcee066c51275630c6\n",
"b'e45h+Hd1IevEyct8XPFL1XSAabxEtiH87gZsUSdWMMY='\n"
]
}
],
"source": [
"# hashes\n",
"\n",
"import base64\n",
"import hashlib\n",
"\n",
"hashed_result = hashlib.sha256(b\"This is a tesu\")\n",
"print(hashed_result.digest())\n",
"print(hashed_result.hexdigest())\n",
"print(base64.b64encode(hashed_result.digest()))\n"
]
},
{
"cell_type": "code",
"execution_count": 13,
"id": "9082c388-1c30-46dc-8897-15bf5db255c8",
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"password_hash1 = 'pbkdf2_sha256$100000$j2jYEb1TvX/wh5JEAYGag6h+hRNTGe3rjyv5pegVBu4=$7cV7MljnJJYuGndge3jozwFP28aP8Gfj+QFGvv5bpfo='\n",
"password_hash2 = 'pbkdf2_sha256$100000$8+PsThJmJXNAbQ/zaR5AgRA/CuNv8L1uPUXRNuWHc9k=$Kf07CSCVQOTQrvWX5l/ZBdA7zsaEFH247QjUaewpxaU='\n"
]
}
],
"source": [
"# PBKDF2\n",
"\n",
"import base64\n",
"import hashlib\n",
"import os\n",
"\n",
"\n",
"def get_password_hash(plaintext_password: str) -> str:\n",
" \"\"\"\n",
" Returns a complete password hash based on `plaintext_password`\n",
"\n",
" :return: The hashed version of `plaintext_password`\n",
" :rtype: str\n",
" \"\"\"\n",
" # parameters typycally sent as arguments or fetched from config\n",
" hash_algo = \"sha256\" # the hash algorithm to use for HMAC\n",
" iterations = 100000 # amount of iterations\n",
"\n",
" salt = os.urandom(32) # 32 bytes of random data\n",
"\n",
" key = hashlib.pbkdf2_hmac(hash_algo, plaintext_password.encode(), salt, iterations)\n",
"\n",
" return (\n",
" f\"pbkdf2_{hash_algo}${iterations}$\"\n",
" f\"{base64.b64encode(salt).decode(\"ascii\")}$\"\n",
" f\"{base64.b64encode(key).decode(\"ascii\")}\"\n",
" )\n",
"\n",
"\n",
"def password_matches(plaintext_password: str, password_hash: str) -> bool:\n",
" \"\"\"Returns True if `plaintext_password` matches `password_hash`, False otherwise\"\"\"\n",
" hash_tokens = password_hash.split(\"$\")\n",
" hash_algo = hash_tokens[0].split(\"_\")[1]\n",
" iterations = int(hash_tokens[1])\n",
" salt = base64.b64decode(hash_tokens[2])\n",
" key = hashlib.pbkdf2_hmac(hash_algo, plaintext_password.encode(), salt, iterations)\n",
" return key == base64.b64decode(hash_tokens[3])\n",
"\n",
"\n",
"password_hash1 = get_password_hash(\"didn't expect a Spanish Inquisition!\")\n",
"password_hash2 = get_password_hash(\"didn't expect a Spanish Inquisition!\")\n",
"print(f\"{password_hash1 = }\")\n",
"print(f\"{password_hash2 = }\")\n",
"\n",
"# print(password_matches(\"didn't expect a Spanish Inquisition!\", 'pbkdf2_sha256$100000$JfwrS72mFimypbwhJ/NCyds2dkXtknvfWM5AM3+Z5GQ=$k8YA8csSJZhuYW0um7utq3+lSX5pTAQPd9dukObWrPo='))"
]
},
{
"cell_type": "code",
"execution_count": 14,
"id": "1274325e-f670-4af8-a0bc-2ff7f668f769",
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"('gxk9W0XFgbzbjRWB7zCPjbWs3', '00000bf5db2c3c6484904bf5e8314aeb123f5594af1f283fb62e14c7d196e84c')\n"
]
}
],
"source": [
"# Proof of work\n",
"\n",
"import hashlib\n",
"import random\n",
"import string\n",
"\n",
"VALID_CHARS = string.ascii_letters + string.digits # valid characters for response\n",
"\n",
"\n",
"def pow_solve_rnd(challenge: str, starting_chars: str = \"00000\", answer_size: int = 25) -> tuple:\n",
" \"\"\"\n",
" Solves a POW challenge for SHA-256 using `random.choice`\n",
"\n",
" :return: (response, SHA-256 digest) tuple that solves the challenge\n",
" :rtype: tuple\n",
" \"\"\"\n",
" while True:\n",
" attempt = ''.join(\n",
" [random.choice(VALID_CHARS) for x in range(answer_size)])\n",
" dig = hashlib.sha256(('{0}:{1}'.format(challenge, attempt)).encode()).hexdigest()\n",
" if dig.startswith(starting_chars):\n",
" return attempt, dig\n",
"\n",
"print(f\"{pow_solve_rnd('2024-08-07')}\")"
]
},
{
"cell_type": "code",
"execution_count": 25,
"id": "6752c055-7e49-46c4-858b-599d069a7e77",
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"enc-val$2$6ppVDmiJi0P9BnHuzwFUPA+vV/Gsb4INe2O9E/Ma2uI=$6879D8rw8645nbQ/NQtY3Q+AwKTWpd1P6Q==\n",
"Invalid tag when decrypting enc-val$2$tmuH3MTDQ9vMbxJ1pZUb0rQlF43Lgr/AYfkA+vSOZs0=$5CVt3VrxhuuOOVt1vCXeGpbhNh/20IcFNg==\n",
"None\n"
]
}
],
"source": [
"# Encryption / decryption using AES-256-GCM\n",
"\n",
"import hashlib\n",
"import os\n",
"\n",
"from cryptography.exceptions import InvalidTag\n",
"from cryptography.hazmat.primitives.ciphers.aead import AESGCM\n",
"\n",
"\n",
"def encrypt(password: str, data: str) -> str:\n",
" \"\"\"\n",
" Encrypts `data` using `password` and AES-256-GCM.\n",
"\n",
" The output string is in the following format:\n",
" enc-val$`version-num`$`bas64-salt`$`base64-encrypted_data`\n",
"\n",
" :param password: The password to generate the key with\n",
" :type password: str\n",
"\n",
" :param data: The data to be encrypted\n",
" :type data: str\n",
"\n",
" :return: The output string\n",
" :rtype: str\n",
" \"\"\"\n",
" data_bytes = data.encode()\n",
" salt = os.urandom(32)\n",
" aesgcm = AESGCM(\n",
" hashlib.scrypt(\n",
" password.encode(), salt=salt, n=2**14, r=8, p=1, dklen=32\n",
" )\n",
" )\n",
" nonce = salt[:12]\n",
" # padding_length_bytes = b\"-1\" # no padding used 2 bytes \"sign\"\n",
" edata = aesgcm.encrypt(\n",
" nonce, data_bytes, salt\n",
" )\n",
" return (\n",
" f\"enc-val$2${base64.b64encode(salt).decode()}${base64.b64encode(edata).decode()}\"\n",
" )\n",
"\n",
"\n",
"def decrypt(password: str, edata: str) -> str:\n",
" \"\"\"\n",
" Decrypts `edata` using `password`.\n",
"\n",
" `edata` is in the following format:\n",
" enc-val$`version-num`$`bas64-salt`$`base64-encrypted_data`\n",
"\n",
" :param password: The password to generate the key with\n",
" :type password: str\n",
"\n",
" :param edata: The data to be decrypted\n",
" :type edata: str\n",
"\n",
" :return: The output string / decrypted data\n",
" :rtype: str\n",
" \"\"\"\n",
" # check for supported versions first...\n",
"\n",
" try:\n",
" salt, data = (base64.b64decode(t) for t in edata[10:].split('$'))\n",
" nonce = salt[:12]\n",
" aesgcm = AESGCM(\n",
" hashlib.scrypt(\n",
" password.encode(), salt=salt, n=2**14, r=8, p=1, dklen=32\n",
" )\n",
" )\n",
"\n",
" # decrypt\n",
" data = aesgcm.decrypt(nonce, data, salt)\n",
" return data.decode()\n",
" except InvalidTag:\n",
" print(f\"Invalid tag when decrypting {edata}\")\n",
"\n",
"print(f\"{encrypt('my passphrase', 'my secret')}\")\n",
"print(f\"{decrypt('my passphrase', 'enc-val$2$tmuH3MTDQ9vMbxJ1pZUb0rQlF43Lgr/AYfkA+vSOZs0=$5CVt3VrxhuuOOVt1vCXeGpbhNh/20IcFNg==')}\")"
]
},
{
"cell_type": "code",
"execution_count": null,
"id": "8ccfb453-d3fd-4383-a01d-f81b19f2cb82",
"metadata": {},
"outputs": [],
"source": []
}
],
"metadata": {
"kernelspec": {
"display_name": "Python 3 (ipykernel)",
"language": "python",
"name": "python3"
},
"language_info": {
"codemirror_mode": {
"name": "ipython",
"version": 3
},
"file_extension": ".py",
"mimetype": "text/x-python",
"name": "python",
"nbconvert_exporter": "python",
"pygments_lexer": "ipython3",
"version": "3.13.9"
}
},
"nbformat": 4,
"nbformat_minor": 5
}
|
