Hash Calculator

Calculate cryptographic hash values for text strings and files. Supports multiple algorithms, file verification, and batch processing.

Quick Start

from scripts.hash_calc import HashCalculator

# Hash text
calc = HashCalculator()
result = calc.hash_text("Hello, World!")
print(result['sha256'])

# Hash file
result = calc.hash_file("document.pdf")
print(result['md5'])

# Verify file integrity
is_valid = calc.verify_file("file.zip", "expected_hash", algorithm="sha256")

Features

• Multiple Algorithms: MD5, SHA1, SHA256, SHA384, SHA512, BLAKE2
• Text Hashing: Hash strings directly
• File Hashing: Efficient streaming for large files
• Verification: Compare against expected hash
• Batch Processing: Hash multiple files
• Checksum Files: Generate/verify checksum files

API Reference

Text Hashing

calc = HashCalculator()

# Single algorithm
md5 = calc.hash_text("Hello", algorithm="md5")

# All algorithms
results = calc.hash_text("Hello")
# {'md5': '...', 'sha1': '...', 'sha256': '...', ...}

# Specific algorithms
results = calc.hash_text("Hello", algorithms=["md5", "sha256"])

File Hashing

# Single file
result = calc.hash_file("document.pdf")
print(result['sha256'])

# Specific algorithm
sha256 = calc.hash_file("file.zip", algorithm="sha256")

Verification

# Verify file against expected hash
is_valid = calc.verify_file(
    "download.iso",
    "a1b2c3d4e5...",
    algorithm="sha256"
)

# Verify text
is_valid = calc.verify_text("password", "5f4dcc3b...", algorithm="md5")

Batch Processing

# Hash all files in directory
results = calc.hash_directory("./files", algorithm="sha256")
# {'file1.txt': 'abc...', 'file2.pdf': 'def...'}

# With recursive option
results = calc.hash_directory("./files", recursive=True)

Checksum Files

# Generate checksum file
calc.generate_checksums("./release", "checksums.sha256", algorithm="sha256")

# Verify against checksum file
results = calc.verify_checksums("checksums.sha256")
# {'file1.zip': True, 'file2.zip': True, 'file3.zip': False}

CLI Usage

# Hash text
python hash_calc.py --text "Hello, World!"

# Hash file
python hash_calc.py --file document.pdf

# Specific algorithm
python hash_calc.py --file document.pdf --algorithm sha256

# Verify file
python hash_calc.py --file download.iso --verify "expected_hash"

# Hash directory
python hash_calc.py --directory ./files --output checksums.txt

# Verify checksums file
python hash_calc.py --verify-checksums checksums.sha256

CLI Arguments

Supported Algorithms

Examples

Verify Download Integrity

calc = HashCalculator()

# Downloaded file and expected hash from website
expected = "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
is_valid = calc.verify_file("ubuntu.iso", expected, algorithm="sha256")

if is_valid:
    print("Download verified successfully!")
else:
    print("WARNING: Hash mismatch - file may be corrupted!")

Generate Release Checksums

calc = HashCalculator()

# Generate checksums for release files
calc.generate_checksums(
    "./release",
    "SHA256SUMS",
    algorithm="sha256"
)

# Output: SHA256SUMS
# e3b0c44298fc1c14...  release-v1.0.zip
# a1b2c3d4e5f6g7h8...  release-v1.0.tar.gz

Password Storage (Example)

calc = HashCalculator()
import os

# Note: In production, use bcrypt/argon2 instead
salt = os.urandom(16).hex()
password = "user_password"
hashed = calc.hash_text(salt + password, algorithm="sha256")

# Store: salt + ":" + hashed
stored = f"{salt}:{hashed}"

Compare Two Files

calc = HashCalculator()

hash1 = calc.hash_file("file1.txt", algorithm="sha256")
hash2 = calc.hash_file("file2.txt", algorithm="sha256")

if hash1 == hash2:
    print("Files are identical")
else:
    print("Files are different")

Output Formats

Text Output

MD5:    5d41402abc4b2a76b9719d911017c592
SHA1:   aaf4c61ddcc5e8a2dabede0f3b482cd9aea9434d
SHA256: 2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824

JSON Output

{
  "input": "hello",
  "md5": "5d41402abc4b2a76b9719d911017c592",
  "sha256": "2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824"
}

Dependencies

(No external dependencies - uses Python standard library)

Security Notes

• MD5 and SHA1 are not collision-resistant (don't use for security)
• Use SHA256 or higher for security applications
• For password hashing, use dedicated libraries (bcrypt, argon2)
• File hashing uses streaming to handle large files efficiently