MIT-Curricular/IS/Lab/Lab3/FileTransfer.py
2025-08-12 02:15:01 +05:30

299 lines
10 KiB
Python

import os
import time
import binascii
from Crypto.PublicKey import RSA, ECC
from Crypto.Cipher import PKCS1_OAEP, AES
from Crypto.Hash import SHA256
from Crypto.Util.Padding import pad, unpad
from Crypto.Random import get_random_bytes
from bokeh.plotting import figure, show, output_file
from bokeh.layouts import gridplot
from bokeh.models import HoverTool
def generate_test_file(size_mb):
"""Generate test file of specified size in MB"""
filename = f"test_file_{size_mb}MB.txt"
with open(filename, 'wb') as f:
# Write random data
for _ in range(size_mb * 1024): # 1MB = 1024KB
f.write(get_random_bytes(1024))
return filename
def rsa_keygen_timed():
"""Generate RSA key pair and measure time"""
start = time.time()
key = RSA.generate(2048)
gen_time = time.time() - start
return key, gen_time
def ecc_keygen_timed():
"""Generate ECC key pair and measure time"""
start = time.time()
key = ECC.generate(curve='secp256r1')
gen_time = time.time() - start
return key, gen_time
def rsa_encrypt_file(filename, pub_key):
"""Encrypt file using RSA with AES hybrid encryption"""
start = time.time()
# Generate AES key
aes_key = get_random_bytes(32) # 256-bit AES key
# Encrypt AES key with RSA
rsa_cipher = PKCS1_OAEP.new(pub_key)
encrypted_aes_key = rsa_cipher.encrypt(aes_key)
# Encrypt file with AES
aes_cipher = AES.new(aes_key, AES.MODE_CBC)
iv = aes_cipher.iv
with open(filename, 'rb') as f:
plaintext = f.read()
padded_plaintext = pad(plaintext, AES.block_size)
ciphertext = aes_cipher.encrypt(padded_plaintext)
enc_time = time.time() - start
encrypted_data = {
'encrypted_aes_key': encrypted_aes_key,
'iv': iv,
'ciphertext': ciphertext
}
return encrypted_data, enc_time
def rsa_decrypt_file(encrypted_data, priv_key):
"""Decrypt file using RSA with AES hybrid decryption"""
start = time.time()
# Decrypt AES key with RSA
rsa_cipher = PKCS1_OAEP.new(priv_key)
aes_key = rsa_cipher.decrypt(encrypted_data['encrypted_aes_key'])
# Decrypt file with AES
aes_cipher = AES.new(aes_key, AES.MODE_CBC, encrypted_data['iv'])
padded_plaintext = aes_cipher.decrypt(encrypted_data['ciphertext'])
plaintext = unpad(padded_plaintext, AES.block_size)
dec_time = time.time() - start
return plaintext, dec_time
def ecc_encrypt_file(filename, pub_key):
"""Encrypt file using ECC with AES hybrid encryption"""
start = time.time()
# Generate ephemeral key pair
eph_private = ECC.generate(curve='secp256r1')
# Compute shared secret
shared_point = pub_key.pointQ * eph_private.d
shared_x = int(shared_point.x)
aes_key = SHA256.new(shared_x.to_bytes(32, 'big')).digest()
# Encrypt file with AES
aes_cipher = AES.new(aes_key, AES.MODE_GCM)
with open(filename, 'rb') as f:
plaintext = f.read()
ciphertext, tag = aes_cipher.encrypt_and_digest(plaintext)
enc_time = time.time() - start
encrypted_data = {
'ephemeral_pub_der': eph_private.public_key().export_key(format='DER'),
'nonce': aes_cipher.nonce,
'tag': tag,
'ciphertext': ciphertext
}
return encrypted_data, enc_time
def ecc_decrypt_file(encrypted_data, priv_key):
"""Decrypt file using ECC with AES hybrid decryption"""
start = time.time()
# Import ephemeral public key
eph_public = ECC.import_key(encrypted_data['ephemeral_pub_der'])
# Compute shared secret
shared_point = eph_public.pointQ * priv_key.d
shared_x = int(shared_point.x)
aes_key = SHA256.new(shared_x.to_bytes(32, 'big')).digest()
# Decrypt file with AES
aes_cipher = AES.new(aes_key, AES.MODE_GCM, nonce=encrypted_data['nonce'])
plaintext = aes_cipher.decrypt_and_verify(encrypted_data['ciphertext'], encrypted_data['tag'])
dec_time = time.time() - start
return plaintext, dec_time
def measure_performance(file_sizes):
"""Measure performance for both RSA and ECC"""
results = {
'file_sizes': file_sizes,
'rsa_keygen': [],
'ecc_keygen': [],
'rsa_encrypt': [],
'rsa_decrypt': [],
'ecc_encrypt': [],
'ecc_decrypt': [],
'rsa_key_size': 0,
'ecc_key_size': 0
}
print("Performance Testing - RSA vs ECC File Transfer")
print("=" * 50)
# Generate keys once
rsa_key, rsa_keygen_time = rsa_keygen_timed()
ecc_key, ecc_keygen_time = ecc_keygen_timed()
# Calculate key sizes
results['rsa_key_size'] = len(rsa_key.export_key('DER'))
results['ecc_key_size'] = len(ecc_key.export_key(format='DER'))
print(f"RSA Key Generation Time: {rsa_keygen_time:.4f} seconds")
print(f"ECC Key Generation Time: {ecc_keygen_time:.4f} seconds")
print(f"RSA Key Size: {results['rsa_key_size']} bytes")
print(f"ECC Key Size: {results['ecc_key_size']} bytes")
print()
for size in file_sizes:
print(f"Testing {size}MB file...")
# Generate test file
filename = generate_test_file(size)
try:
# RSA performance
rsa_pub = rsa_key.publickey()
encrypted_rsa, rsa_enc_time = rsa_encrypt_file(filename, rsa_pub)
decrypted_rsa, rsa_dec_time = rsa_decrypt_file(encrypted_rsa, rsa_key)
# ECC performance
ecc_pub = ecc_key.public_key()
encrypted_ecc, ecc_enc_time = ecc_encrypt_file(filename, ecc_pub)
decrypted_ecc, ecc_dec_time = ecc_decrypt_file(encrypted_ecc, ecc_key)
# Store results
results['rsa_keygen'].append(rsa_keygen_time)
results['ecc_keygen'].append(ecc_keygen_time)
results['rsa_encrypt'].append(rsa_enc_time)
results['rsa_decrypt'].append(rsa_dec_time)
results['ecc_encrypt'].append(ecc_enc_time)
results['ecc_decrypt'].append(ecc_dec_time)
print(f" RSA - Encrypt: {rsa_enc_time:.4f}s, Decrypt: {rsa_dec_time:.4f}s")
print(f" ECC - Encrypt: {ecc_enc_time:.4f}s, Decrypt: {ecc_dec_time:.4f}s")
finally:
# Clean up test file
if os.path.exists(filename):
os.remove(filename)
print()
return results
def create_performance_graphs(results):
"""Create performance comparison graphs using Bokeh"""
output_file("file_transfer_performance.html")
file_sizes = results['file_sizes']
# Encryption time comparison
p1 = figure(title="Encryption Time Comparison", x_axis_label="File Size (MB)",
y_axis_label="Time (seconds)", width=400, height=300)
p1.line(file_sizes, results['rsa_encrypt'], legend_label="RSA", line_color="red", line_width=2)
p1.circle(file_sizes, results['rsa_encrypt'], color="red", size=6)
p1.line(file_sizes, results['ecc_encrypt'], legend_label="ECC", line_color="blue", line_width=2)
p1.circle(file_sizes, results['ecc_encrypt'], color="blue", size=6)
p1.legend.location = "top_left"
# Decryption time comparison
p2 = figure(title="Decryption Time Comparison", x_axis_label="File Size (MB)",
y_axis_label="Time (seconds)", width=400, height=300)
p2.line(file_sizes, results['rsa_decrypt'], legend_label="RSA", line_color="red", line_width=2)
p2.circle(file_sizes, results['rsa_decrypt'], color="red", size=6)
p2.line(file_sizes, results['ecc_decrypt'], legend_label="ECC", line_color="blue", line_width=2)
p2.circle(file_sizes, results['ecc_decrypt'], color="blue", size=6)
p2.legend.location = "top_left"
# Key generation comparison
p3 = figure(title="Key Generation Time", x_axis_label="Algorithm",
y_axis_label="Time (seconds)", width=400, height=300,
x_range=["RSA", "ECC"])
p3.vbar(x=["RSA", "ECC"], top=[results['rsa_keygen'][0], results['ecc_keygen'][0]],
width=0.5, color=["red", "blue"])
# Key size comparison
p4 = figure(title="Key Size Comparison", x_axis_label="Algorithm",
y_axis_label="Size (bytes)", width=400, height=300,
x_range=["RSA", "ECC"])
p4.vbar(x=["RSA", "ECC"], top=[results['rsa_key_size'], results['ecc_key_size']],
width=0.5, color=["red", "blue"])
# Create grid layout
grid = gridplot([[p1, p2], [p3, p4]])
show(grid)
def print_security_analysis():
"""Print security analysis and comparison"""
print("\nSecurity Analysis - RSA vs ECC")
print("=" * 50)
print("RSA (2048-bit):")
print(" • Security Level: ~112 bits")
print(" • Key Size: Large (2048+ bits)")
print(" • Resistance: Integer factorization problem")
print(" • Quantum Threat: Vulnerable to Shor's algorithm")
print(" • Computational Overhead: High for large keys")
print()
print("ECC (secp256r1):")
print(" • Security Level: ~128 bits")
print(" • Key Size: Small (256 bits)")
print(" • Resistance: Elliptic curve discrete logarithm problem")
print(" • Quantum Threat: Vulnerable to modified Shor's algorithm")
print(" • Computational Overhead: Lower than equivalent RSA")
print()
print("Summary:")
print(" • ECC provides equivalent security with smaller keys")
print(" • ECC is more efficient for mobile/embedded systems")
print(" • RSA is more widely supported and established")
print(" • Both require post-quantum alternatives for future security")
def main():
"""Main function to run the file transfer comparison"""
file_sizes = [1, 5, 10] # MB
print("Secure File Transfer System - RSA vs ECC Comparison")
print("=" * 60)
# Measure performance
results = measure_performance(file_sizes)
# Create performance graphs
create_performance_graphs(results)
# Print security analysis
print_security_analysis()
print(f"\nPerformance graphs saved to: file_transfer_performance.html")
print("Open the HTML file in your browser to view the interactive graphs.")
if __name__ == '__main__':
main()