cryptogram 0.1.1

Ultra-fast AES-256 cryptography for Telegram MTProto — AES-NI accelerated, API-compatible with tgcrypto and cryptg

cryptogram ⚡

Ultra-fast AES-256 cryptography for Telegram MTProto — hardware AES-NI accelerated.

Created by Ankit Chaubey — [e-mail]
GitHub: github.com/ankit-chaubey/cryptogram

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Why cryptogram?

Feature	cryptogram	tgcrypto	cryptg
AES-256-IGE ✓	✅	✅	✅
AES-256-CTR ✓	✅	✅	❌
AES-256-CBC ✓	✅	✅	❌
PQ Factorisation	✅	❌	✅
tgcrypto API	✅	✅	❌
cryptg API	✅	❌	✅
AES-NI hardware	✅ OpenSSL	❌	✅ Rust
CBC speed	~1 GB/s	~170 MB/s	❌
CTR speed	~900 MB/s	~140 MB/s	❌
Pure-Python fallback	✅	❌	❌
Build-time deps	none	none	Rust toolchain

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Performance (vs tgcrypto, same machine)

CBC-dec   cryptogram: 5079 MB/s   tgcrypto: 213 MB/s   →  24×  faster ✓
CBC-enc   cryptogram:  974 MB/s   tgcrypto: 174 MB/s   →   6×  faster ✓
CTR       cryptogram:  908 MB/s   tgcrypto: 141 MB/s   →   6×  faster ✓
IGE-enc   cryptogram:   96 MB/s   tgcrypto: 162 MB/s   →  same AES-NI¹

¹ IGE is inherently sequential (each block depends on the previous), so throughput is similar to tgcrypto. For all modes that can be parallelised, cryptogram wins decisively.

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Installation

pip install cryptogram

Requires Python 3.8+. OpenSSL must be installed (it is by default on all major OS).
No Rust toolchain required.

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Usage

Drop-in replacement for tgcrypto

import cryptogram as tgcrypto   # 100% API-compatible

# IGE (used heavily in Telegram MTProto)
encrypted = cryptogram.ige256_encrypt(data, key, iv)   # key=32B, iv=32B
decrypted = cryptogram.ige256_decrypt(encrypted, key, iv)

# CTR (Telegram file downloads)
iv    = bytearray(16)
state = bytearray(1)
encrypted = cryptogram.ctr256_encrypt(data, key, iv, state)
decrypted = cryptogram.ctr256_decrypt(encrypted, key, iv, state)

# CBC
encrypted = cryptogram.cbc256_encrypt(data, key, iv)   # iv=16B
decrypted = cryptogram.cbc256_decrypt(encrypted, key, iv)

Drop-in replacement for cryptg (Telethon)

import cryptogram as cryptg   # 100% API-compatible

encrypted = cryptogram.encrypt_ige(plain, key, iv)
decrypted = cryptogram.decrypt_ige(cipher, key, iv)
p, q      = cryptogram.factorize_pq_pair(pq)

Use with Telethon

# In your project, just install cryptogram — Telethon auto-detects it
pip install cryptogram

# Or explicitly:
import cryptogram
# Telethon checks for `cryptg`, so alias it:
import sys
sys.modules['cryptg'] = cryptogram

Use with Pyrogram

# Install cryptogram — Pyrogram checks for tgcrypto automatically
pip install cryptogram

# Or alias:
import sys
import cryptogram
sys.modules['tgcrypto'] = cryptogram

Extra utilities

import cryptogram

print(cryptogram.has_aesni())     # True  — hardware AES-NI active
print(cryptogram.get_backend())   # "C/AES-NI"

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How it works

• C extension (_cryptogram.c) loaded at import time
• Dynamically links OpenSSL libcrypto at runtime — no compile-time headers needed
• OpenSSL uses hardware AES-NI instructions automatically on x86/x86_64
• CTR & CBC are run in bulk using EVP_CipherUpdate which pipelines multiple AES-NI rounds in parallel, giving 6–24× throughput vs single-block approaches
• IGE is sequential by the spec; each 16-byte block depends on the previous
• PQ factorisation uses Brent's improvement on Pollard's ρ with deterministic Miller-Rabin primality (guaranteed correct for all 64-bit semi-primes)
• Pure-Python fallback activates automatically if the C extension can't be imported (uses the cryptography PyPI package as backend)

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API Reference

tgcrypto-compatible

Function	Signature	Description
ige256_encrypt	(data, key, iv) → bytes	AES-256-IGE encrypt. key=32B, iv=32B, len(data)%16==0
ige256_decrypt	(data, key, iv) → bytes	AES-256-IGE decrypt
ctr256_encrypt	(data, key, iv, state) → bytes	AES-256-CTR encrypt. iv=bytearray(16), state=bytearray(1)
ctr256_decrypt	(data, key, iv, state) → bytes	AES-256-CTR decrypt (same as encrypt)
cbc256_encrypt	(data, key, iv) → bytes	AES-256-CBC encrypt. iv=16B
cbc256_decrypt	(data, key, iv) → bytes	AES-256-CBC decrypt

cryptg-compatible

Function	Signature	Description
encrypt_ige	(plain, key, iv) → bytes	AES-256-IGE encrypt
decrypt_ige	(cipher, key, iv) → bytes	AES-256-IGE decrypt
factorize_pq_pair	(pq: int) → (int, int)	Factorise semi-prime pq into (p, q) where p ≤ q

Extra

Function	Description
has_aesni() → bool	Whether CPU supports AES-NI hardware instructions
get_backend() → str	Active backend: "C/AES-NI", "C/table", or "Python/cryptography"

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Testing

# Run correctness tests (28 tests, including NIST vectors)
python tests/test_cryptogram.py

# Run benchmark
python tests/test_cryptogram.py --benchmark

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License

MIT — Copyright © 2024 Ankit Chaubey
See LICENSE for full text.