hash-calculator
Calculate cryptographic hashes (MD5, SHA1, SHA256, SHA512) for text and files. Compare hashes, verify integrity, and batch process directories.
When & Why to Use This Skill
The Hash Calculator skill is a comprehensive cryptographic utility designed to generate and verify hash values (MD5, SHA1, SHA256, SHA512, BLAKE2) for both text strings and physical files. It optimizes data integrity workflows through efficient streaming for large files, batch directory processing, and automated checksum file generation, providing a reliable solution for developers and system administrators to ensure data authenticity.
Use Cases
- Verifying Download Integrity: Ensure downloaded software, ISO images, or installers are not corrupted or tampered with by comparing their SHA256 hashes against official provider checksums.
- Automated Release Management: Generate standardized checksum files (e.g., SHA256SUMS) for software distribution packages to provide users with a verifiable audit trail.
- Data Deduplication and Cleanup: Identify identical files across large storage volumes by comparing cryptographic signatures, facilitating efficient disk space management.
- Security Auditing and Monitoring: Establish a baseline of file hashes for critical system components to detect unauthorized modifications or potential security breaches.
- Development and Testing: Quickly generate salted hashes or verify data consistency during the development of authentication systems and data pipelines.
| name | hash-calculator |
|---|---|
| description | Calculate cryptographic hashes (MD5, SHA1, SHA256, SHA512) for text and files. Compare hashes, verify integrity, and batch process directories. |
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
| Argument | Description | Default |
|---|---|---|
--text |
Text to hash | - |
--file |
File to hash | - |
--directory |
Directory to hash | - |
--algorithm |
Hash algorithm | all |
--verify |
Expected hash to verify | - |
--output |
Output file | - |
--recursive |
Recursive directory | False |
--verify-checksums |
Verify checksum file | - |
Supported Algorithms
| Algorithm | Output Length | Use Case |
|---|---|---|
md5 |
128 bits (32 hex) | Legacy, checksums (not secure) |
sha1 |
160 bits (40 hex) | Legacy (not secure) |
sha256 |
256 bits (64 hex) | General purpose, secure |
sha384 |
384 bits (96 hex) | High security |
sha512 |
512 bits (128 hex) | Maximum security |
blake2b |
512 bits | Modern, fast |
blake2s |
256 bits | Modern, fast, small |
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