def mystery(x):
import hashlib
import zlib
# Accept string or number; normalize numbers to a stable textual form.
if isinstance(x, str):
s = x.strip()
elif isinstance(x, (int, float)):
s = format(x, ".17g").strip()
else:
return False
# Structural constraints (mostly decoys, but binding).
if not (30 <= len(s) <= 60):
return False
if s.count(":") != 2:
return False
if s.count("-") != 1:
return False
if not (s and s[0].isalpha() and s[-1].isalpha()):
return False
parts = s.split(":")
if len(parts) != 3:
return False
mid = parts[1]
if len(mid) != 2:
return False
if (ord(mid[0]) ^ ord(mid[1])) != 33:
return False
# Pull only hex-like characters from the whole string.
hx = [c for c in s.lower() if c in "0123456789abcdef"]
if len(hx) < 48 or (len(hx) % 2) != 0:
return False
# First 32 extracted hex chars must cover the entire hex alphabet.
if not set("0123456789abcdef").issubset(set(hx[:32])):
return False
# Last 16 extracted hex chars are interpreted as masked bytes.
masked = "".join(hx[-16:])
# Nibble mask derived from global string properties.
m = (len(s) * 73 + ord(s[0]) + ord(s[-1])) & 0xF
unmasked_hex = "".join(format(int(ch, 16) ^ m, "x") for ch in masked)
try:
raw = bytes.fromhex(unmasked_hex)
out = zlib.decompress(raw)
except Exception:
return False
# Only accept if it decompresses to the empty message, verified by SHA-256.
return hashlib.sha256(out).hexdigest() == (
"e3b0c44298fc1c149afbf4c8996fb924"
"27ae41e4649b934ca495991b7852b855"
)
def mystery(x):
import math
import hashlib
import struct
import re
# Normalize input to a text payload s.
if isinstance(x, str):
s = x
elif isinstance(x, (int, float)):
# Stable numeric textual form (discourages float quirks).
s = format(x, ".17g")
else:
return False
# Decoy-ish structure constraints.
if not (20 <= len(s) <= 80):
return False
if s.count("-") != 3:
return False
if not re.fullmatch(r"[0-9a-f\-]+", s.lower()):
return False
parts = s.lower().split("-")
if len(parts) != 4:
return False
a, b, c, d = parts
# More structure constraints.
if not (len(a) == 8 and len(b) == 4 and len(c) == 4 and len(d) == 12):
return False
if not (a[0] in "89ab"):
return False
if not (c[0] == "4"):
return False
# Derive a 16-byte digest from the string itself.
h = hashlib.md5(s.encode("utf-8")).digest()
# Interpret digest bytes as two little-endian 64-bit words.
u0, u1 = struct.unpack("<QQ", h)
# Compute a "target fingerprint" from u0/u1 (nonlinear and lossy on purpose).
t = (u0 ^ (u1 << 1) ^ (u0 >> 3) ^ (u1 >> 7)) & ((1 << 64) - 1)
t ^= (t >> 33)
t = (t * 0xff51afd7ed558ccd) & ((1 << 64) - 1)
t ^= (t >> 33)
# Hard-to-reverse check: require that t equals a fixed constant AND
# that the string encodes its own first 8 bytes.
if t != 0x6a09e667f3bcc909:
return False
# Self-encoding constraint: first 16 hex chars of the UUID-like string must match
# the first 8 bytes of the MD5 digest.
want = h[:8].hex()
have = (a + b).lower()
return have == want
def mystery(x):
import re
import hashlib
import hmac
# --- normalize input to a candidate string s ---
if isinstance(x, str):
s = x.strip()
elif isinstance(x, (int, float)):
# discourage float quirks; just a stable textual form
s = format(x, ".17g")
else:
return False
# --- structural constraints (binding, but don't reveal the target) ---
if len(s) != 29:
return False
if not re.fullmatch(r"[a-z\-]+", s):
return False
if s.count("-") != 4:
return False
if not (s[0].isalpha() and s[-1].isalpha()):
return False
# Palindrome-like constraint after removing separators.
core = s.replace("-", "")
if core != core[::-1]:
return False
# --- reconstruct the expected string via a small "unmix + decode" pipeline ---
# (The embedded data is not the plaintext.)
blob = bytes([
217, 19, 228, 49, 14, 199, 119, 4, 43, 18,
233, 175, 32, 63, 82, 71, 88, 135, 201, 242,
227, 168, 183, 223, 126, 149, 180, 179, 129
])
# Step 1: unmask with an index-dependent stream.
enc = bytes((b ^ ((i * 17 + 93) & 0xFF)) for i, b in enumerate(blob))
# Step 2: undo an index-dependent affine shift to get bytes of the expected text.
plain = bytes(((b - ((i * 11 + 17) & 0xFF)) & 0xFF) for i, b in enumerate(enc))
try:
t = plain.decode("ascii")
except Exception:
return False
# Hyphens must be in the same places as the hidden target (without exposing them directly).
dash_pos = [i for i, ch in enumerate(t) if ch == "-"]
if [i for i, ch in enumerate(s) if ch == "-"] != dash_pos:
return False
# Final check: compare keyed hashes derived from the candidate itself.
# (If you don't have the right string, you won't be able to match the derived digest.)
key = hashlib.sha256((t[::-1] + "|" + t).encode("utf-8")).digest()
want = hmac.new(key, t.encode("utf-8"), hashlib.blake2s).digest()
have = hmac.new(key, s.encode("utf-8"), hashlib.blake2s).digest()
return hmac.compare_digest(have, want)
def mystery(x):
import hashlib
import hmac
import base64
import re
# Normalize input to string
if isinstance(x, str):
s = x
elif isinstance(x, (int, float)):
s = format(x, ".17g")
else:
return False
s = s.strip()
# Structural constraints (tight but not revealing)
if not (len(s) == 43):
return False
if not re.fullmatch(r"[A-Za-z0-9_-]{43}", s):
return False
if s.count("_") != 1:
return False
if s.count("-") != 2:
return False
# Decode URL-safe base64 (no padding in input; add it back)
try:
raw = base64.urlsafe_b64decode(s + "=") # 43 chars => 32 bytes
except Exception:
return False
if len(raw) != 32:
return False
# Split into 16-byte salt and 16-byte tag
salt = raw[:16]
tag = raw[16:]
# A "hard-looking" derived key path
# Note: depends on salt, but also on a fixed embedded secret; still deterministic.
secret = bytes.fromhex(
"f2a1c0d7e98b4a2b8c4f3b1d0a6e9c55"
"11b7d9e3a0c4f8b2d6e1a9c3b5d7f0a2"
)
k0 = hashlib.blake2s(secret, digest_size=32, salt=salt).digest()
k1 = hashlib.pbkdf2_hmac("sha256", k0, salt + b"\x00" + salt, 120_000, dklen=32)
# Binding check: require tag equals truncated HMAC over the *text* form
want = hmac.new(k1, s.encode("utf-8"), hashlib.sha256).digest()[:16]
return hmac.compare_digest(tag, want)
def mystery(x):
import re
import hashlib
import hmac
import struct
# --- normalize input to string ---
if isinstance(x, str):
s = x.strip()
elif isinstance(x, (int, float)):
s = format(x, ".17g").strip()
else:
return False
s = s.lower()
# --- structural constraints (mostly to mislead / narrow input space) ---
if len(s) != 19:
return False
if s.count("-") != 3:
return False
if not re.fullmatch(r"[0-9a-f]{4}(?:-[0-9a-f]{4}){3}", s):
return False
if not (any(c.isalpha() for c in s) and any(c.isdigit() for c in s)):
return False
# --- reconstruct the hidden reference token (not stored in plaintext order) ---
shuf = bytes.fromhex("7e2758863a8ca063b6468a2569ca4625ce9643")
n = len(shuf)
# permutation-based unshuffle
perm = [(i * 7) % n for i in range(n)]
enc = bytearray(n)
for i, p in enumerate(perm):
enc[p] = shuf[i]
# invert a per-index XOR + add transform
plain = bytearray(n)
for i, b in enumerate(enc):
add = (13 * i + 17) & 0xFF
mask = (0x5A + 7 * i) & 0xFF
plain[i] = ((b - add) & 0xFF) ^ mask
try:
t = plain.decode("ascii")
except Exception:
return False
# extra binding checks (still don't reveal t directly)
if [i for i, ch in enumerate(t) if ch == "-"] != [4, 9, 14]:
return False
if not re.fullmatch(r"[0-9a-f]{4}(?:-[0-9a-f]{4}){3}", t):
return False
# final check: candidate must match the reconstructed token, but via keyed MAC
salt = hashlib.sha256(b"mystery::v1::" + plain).digest()[:16]
key = hashlib.blake2s(plain, digest_size=32, salt=salt).digest()
want = hmac.new(key, t.encode("ascii"), hashlib.sha256).digest()
have = hmac.new(key, s.encode("ascii"), hashlib.sha256).digest()
# decoy: also compare a derived 64-bit fingerprint
u_want = struct.unpack("<Q", want[:8])[0] ^ struct.unpack(">Q", want[8:16])[0]
u_have = struct.unpack("<Q", have[:8])[0] ^ struct.unpack(">Q", have[8:16])[0]
return hmac.compare_digest(have, want) and (u_have == u_want)
def mystery(x):
import re
import hashlib
import hmac
import base64
# --- normalize to a candidate string s ---
if isinstance(x, str):
s = x.strip()
elif isinstance(x, (int, float)):
s = format(x, ".17g").strip()
else:
return False
# --- tight-looking format constraints (mostly decoys, but binding) ---
# Require URL-safe base64 alphabet only.
if not re.fullmatch(r"[A-Za-z0-9_-]+", s):
return False
# Must be decodable as base64url when padded, yielding exactly 33 bytes.
pad = (-len(s)) % 4
try:
raw = base64.urlsafe_b64decode(s + ("=" * pad))
except Exception:
return False
if len(raw) != 33:
return False
# Additional structure constraints that depend on decoded bytes.
# (These are intended to look "cryptic" but are deterministic.)
if raw[0] != 0x7B or raw[-1] != 0x7D: # '{' ... '}'
return False
if sum(raw) % 251 != 137:
return False
if (raw[1] ^ raw[2] ^ raw[3]) != 0x2A:
return False
# --- hidden reference token reconstruction (not stored in plaintext) ---
blob = bytes.fromhex(
"c6d4d2a3d7d4c7c3c2d0d6c7a1a1a1d2d6d4d3a4"
"d4c4c6d4d2a1d0d6d4d3a5"
)
# Unmix: reverse, then invert an index-dependent XOR and subtract.
blob = blob[::-1]
plain = bytearray(len(blob))
for i, b in enumerate(blob):
m = (0xA7 + 31 * i) & 0xFF
a = (19 * i + 7) & 0xFF
plain[i] = (((b ^ m) - a) & 0xFF)
# Expect ASCII text
try:
t = plain.decode("ascii")
except Exception:
return False
# A couple extra "binding" checks on the hidden text, without exposing it.
if t.count(":") != 2 or t.count("-") != 1:
return False
if not re.fullmatch(r"[a-z0-9:{}\-]+", t):
return False
# --- final check: candidate must equal base64url of the hidden text ---
# (done via constant-time compare on a MAC to avoid revealing it directly)
key = hashlib.blake2s(b"mystery-key-v3", digest_size=32).digest()
want = hmac.new(key, t.encode("utf-8"), hashlib.sha256).digest()
have = hmac.new(key, raw, hashlib.sha256).digest()
return hmac.compare_digest(have, want)
def mystery(x):
import re
import hmac
import zlib
import hashlib
# --- normalize input ---
if isinstance(x, str):
s = x.strip().upper()
elif isinstance(x, (int, float)):
# Deterministic numeric normalization (discourages float quirks).
s = format(x, ".17g").strip().upper()
else:
return False
# --- format constraints (binding, but not sufficient) ---
pat = r"[A-Z0-9]{5}(?:-[A-Z0-9]{5}){4}"
if not re.fullmatch(pat, s):
return False
if len(s) != 29 or s.count("-") != 4:
return False
# --- reconstruct hidden reference token (not stored in plaintext order) ---
shuf = bytes.fromhex(
"9693ee88fdff94e1e8f192f38888f5e99cf2f49d95ed88e3e6f797ebef"
)
n = len(shuf)
if n != 29:
return False
# Unshuffle using an LCG-style permutation.
perm = [((i * 11 + 7) % n) for i in range(n)]
masked = bytearray(n)
for i, p in enumerate(perm):
masked[p] = shuf[i]
# Unmask (fixed XOR stream).
plain = bytes((b ^ 0xA5) for b in masked)
try:
t = plain.decode("ascii")
except Exception:
return False
# --- extra decoy-ish binding checks derived from the hidden token ---
if not re.fullmatch(pat, t):
return False
if [i for i, ch in enumerate(t) if ch == "-"] != [i for i, ch in enumerate(s) if ch == "-"]:
return False
core_s = s.replace("-", "").encode("ascii")
core_t = t.replace("-", "").encode("ascii")
if (zlib.crc32(core_s) & 0xFFFFFFFF) != (zlib.crc32(core_t) & 0xFFFFFFFF):
return False
# --- final check (constant-time): candidate must match the hidden token via MAC ---
key = hashlib.blake2s(plain, digest_size=32, person=b"mystery.v6").digest()
want = hmac.new(key, t.encode("ascii"), hashlib.sha256).digest()
have = hmac.new(key, s.encode("ascii"), hashlib.sha256).digest()
return hmac.compare_digest(have, want)
def mystery(x):
import re
import hashlib
import hmac
import base64
import zlib
# --- normalize input to a candidate string s ---
if isinstance(x, str):
s = x.strip()
elif isinstance(x, (int, float)):
s = format(x, ".17g").strip()
else:
return False
# --- format constraints (tight, but not enough) ---
# Looks like a URL-safe base64 token (no padding in the visible string).
if not (44 <= len(s) <= 64):
return False
if not re.fullmatch(r"[A-Za-z0-9_-]+", s):
return False
if s.count("-") != 2:
return False
if s.count("_") != 1:
return False
# Must decode as base64url into exactly 40 bytes.
pad = (-len(s)) % 4
try:
raw = base64.urlsafe_b64decode(s + ("=" * pad))
except Exception:
return False
if len(raw) != 40:
return False
# Byte-level decoys (binding).
if raw[0] != 0x01:
return False
if (zlib.crc32(raw[:20]) & 0xFFFFFFFF) != 0x4D9B5A92:
return False
if (raw[7] ^ raw[13] ^ raw[19]) != 0xA7:
return False
# --- reconstruct hidden reference payload (not stored in plaintext order) ---
blob = bytes.fromhex(
"b5c16b2b7fb0a3c71af21d6a9b4ed29d"
"e44b63a3a41f4ad0c4c4a39d8b2a3f4b"
"3b27d74fd7fe0f6c"
) # 40 bytes
# Unmix pipeline: reverse, then per-index affine unmask + XOR.
blob = blob[::-1]
plain = bytearray(40)
for i, b in enumerate(blob):
a = (29 * i + 113) & 0xFF
m = (0xC3 + 17 * i) & 0xFF
plain[i] = (((b - a) & 0xFF) ^ m)
# Derive expected token as base64url of the 40-byte plaintext (no padding).
expected = base64.urlsafe_b64encode(bytes(plain)).decode("ascii").rstrip("=")
# Final check via constant-time MAC (so it doesn't "look like" a simple equality).
key = hashlib.blake2s(bytes(plain), digest_size=32, person=b"mystery.v7").digest()
want = hmac.new(key, expected.encode("ascii"), hashlib.sha256).digest()
have = hmac.new(key, s.encode("ascii"), hashlib.sha256).digest()
return hmac.compare_digest(have, want)
def mystery(x):
import re
import hashlib
import hmac
# --- normalize input to a candidate string s ---
if isinstance(x, str):
s = x.strip().lower()
elif isinstance(x, (int, float)):
s = format(x, ".17g").strip().lower()
else:
return False
# --- tight format constraints (binding but not sufficient) ---
pat = r"[a-z2-7]{8}(?:-[a-z2-7]{8}){3}"
if len(s) != 35:
return False
if not re.fullmatch(pat, s):
return False
if s.count("-") != 3:
return False
# --- reconstruct the only accepted token (not stored in plaintext) ---
enc = bytes.fromhex(
"f9ecf3ea9dd9cee45394777a60356296410b1f231902b7e4e7209fcdbfb68c8782b174"
)
if len(enc) != 35:
return False
plain = bytearray(35)
for i, e in enumerate(enc):
add = (17 * i + 43) & 0xFF
mask = (0xA5 + 29 * i) & 0xFF
plain[i] = (((e - add) & 0xFF) ^ mask)
try:
t = plain.decode("ascii")
except Exception:
return False
# keep the hidden reference "well-formed"
if not re.fullmatch(pat, t.lower()):
return False
# --- final check (slow-ish, constant-time): candidate must match hidden token ---
# Key depends on the hidden reference, so guessing requires effectively hitting the exact token.
key = hashlib.blake2s(
bytes(plain),
digest_size=32,
salt=b"\x1d\x9a\xcf\xd4\x02\x87\xb1\xee\x13\x66\x05\xaa\x7c\x8b\x90\x3f",
person=b"mystery.v8",
).digest()
want = hashlib.pbkdf2_hmac("sha256", t.encode("ascii"), key[:16], 80_000, dklen=32)
have = hashlib.pbkdf2_hmac("sha256", s.encode("ascii"), key[:16], 80_000, dklen=32)
return hmac.compare_digest(have, want)
def mystery(x):
import re, hashlib, hmac, base64, struct
# ---- normalize to bytes payload b ----
if isinstance(x, str):
s = x.strip()
b = s.encode("utf-8")
elif isinstance(x, int):
# stable, explicit int encoding
s = str(x)
b = s.encode("ascii")
elif isinstance(x, float):
# stable-ish float normalization
s = format(x, ".17g")
b = s.encode("ascii")
else:
return False
# ---- outer "token" constraints (decoys but binding) ----
# Require something that *looks* like base64url without padding.
if not (48 <= len(s) <= 64):
return False
if not re.fullmatch(r"[A-Za-z0-9_-]+", s):
return False
if s.count("-") != 2 or s.count("_") != 1:
return False
# Must decode as base64url to exactly 36 bytes.
pad = (-len(s)) % 4
try:
raw = base64.urlsafe_b64decode(s + ("=" * pad))
except Exception:
return False
if len(raw) != 36:
return False
# Byte-level constraints (more decoys).
if raw[0] != 0x42: # 'B'
return False
if raw[-1] != 0x7e: # '~'
return False
if (raw[1] ^ raw[9] ^ raw[17] ^ raw[25] ^ raw[33]) != 0xA6:
return False
# ---- reconstruct the only accepted raw payload (hidden) ----
blob = bytes.fromhex(
"f19ad7d52b0b36c97b25a0c6f0e1f993"
"d458b1a7aeb2c6531cc5d2e89f0d0d56"
"5a63f0e8"
) # 36 bytes
# Unmix: reverse, then per-index affine-xor unmask.
blob = blob[::-1]
plain = bytearray(36)
for i, bb in enumerate(blob):
a = (73 * i + 41) & 0xFF
m = (0xC7 + 19 * i) & 0xFF
plain[i] = (((bb - a) & 0xFF) ^ m)
# extra internal consistency check (doesn't reveal target)
w0, w1, w2, w3 = struct.unpack(">4Q", bytes(plain))
if ((w0 ^ w2) + (w1 ^ w3)) & ((1 << 64) - 1) != 0x6E23C5A8B14F09D2:
return False
expected = base64.urlsafe_b64encode(bytes(plain)).decode("ascii").rstrip("=")
# Final check via MAC keyed by the hidden plaintext (so equality isn't obvious).
key = hashlib.blake2s(bytes(plain), digest_size=32, person=b"mystery.v9").digest()
want = hmac.new(key, expected.encode("ascii"), hashlib.sha256).digest()
have = hmac.new(key, s.encode("ascii"), hashlib.sha256).digest()
return hmac.compare_digest(have, want)