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diff --git a/utils/README.md b/utils/README.md deleted file mode 100644 index 3a8791c..0000000 --- a/utils/README.md +++ /dev/null @@ -1,158 +0,0 @@ -Utilities -========= - -A couple of useful utilities are built on top of the library. -Each of the utilities accepts the `--help` flag, which can be used to examine -utility's detailed usage information. - -Block encryption ----------------- - -Block encryption utilities can produce verbose human-readable output, including -round keys, intermediate initialization vector values, etc. -They are primarily intended for debugging purposes. -Enable verbose output by passing the `--verbose` flag. -Please note that verbose output can only be produced when *not* using the -"boxes" interface (the `--use-boxes` flag). - -### encrypt_block - -Encrypts blocks using the selected algorithm in the specified mode of -operation. - -For example, to encrypt - -* the plaintext block `0x00112233445566778899aabbccddeeff` -* using AES-128 in ECB mode -* with key `0x000102030405060708090a0b0c0d0e0f`, - -run: - - encrypt_block -a aes128 -m ecb 000102030405060708090a0b0c0d0e0f 00112233445566778899aabbccddeeff - -To encrypt - -* the plaintext block `0x00112233445566778899aabbccddeeff` -* using AES-192 in OFB mode -* with initialization vector `0x22222222222222222222222222222222` -* and key `0x000102030405060708090a0b0c0d0e0f101112131415161718`, - -run: - - encrypt_block -a aes192 -m ofb 000102030405060708090a0b0c0d0e0f101112131415161718 22222222222222222222222222222222 00112233445566778899aabbccddeeff - -### decrypt_block - -Decrypts blocks using the selected algorithm in the specified mode of -operation. - -For example, to decrypt - -* the ciphertext block `0x69c4e0d86a7b0430d8cdb78070b4c55a` -* using AES-128 in ECB mode -* with key `0x000102030405060708090a0b0c0d0e0f`, - -run: - - decrypt_block -a aes128 -m ecb 000102030405060708090a0b0c0d0e0f 69c4e0d86a7b0430d8cdb78070b4c55a - -To decrypt - -* the ciphertext block `0x762a5ab50929189cefdb99434790aad8` -* using AES-192 in OFB mode -* with initialization vector `0x22222222222222222222222222222222` -* and key `0x000102030405060708090a0b0c0d0e0f101112131415161718`, - -run: - - decrypt_block -a aes192 -m ofb 000102030405060708090a0b0c0d0e0f101112131415161718 22222222222222222222222222222222 bda298884f5c3a9eb7068aa7063a3b75 - -File encryption ---------------- - -### encrypt_file - -Encrypts a file using the selected algorithm in the specified mode of -operation. - -For example, to encrypt the plaintext from "input.txt" - -* using AES-128 in ECB mode -* with key `0x11111111111111111111111111111111` -* and write the ciphertext to "output.txt", - -run: - - encrypt_file -a aes128 -m ecb -k 11111111111111111111111111111111 -i input.txt -o output.txt - -To encrypt the plaintext from "input.txt" - -* using AES-192 in OFB mode -* with key `0x111111111111111111111111111111111111111111111111` -* and initialization vector `0x22222222222222222222222222222222` -* and write the ciphertext to "output.txt": - -run - - encrypt_file -a aes192 -m ofb -k 111111111111111111111111111111111111111111111111 -v 22222222222222222222222222222222 -i input.txt -o output.txt - -### decrypt_file - -Decrypts a file using the selected algorithm in the specified mode of -operation. - -To decrypt the ciphertext from "input.txt" - -* using AES-128 in ECB mode -* with key `0x11111111111111111111111111111111` -* and write the plaintext to "output.txt", - -run - - decrypt_file -a aes128 -m ecb -k 11111111111111111111111111111111 -i input.txt -o output.txt - -To decrypt the ciphertext from "input.txt" - -* using AES-192 in OFB mode -* with key `0x111111111111111111111111111111111111111111111111` -* and initialization vector `0x22222222222222222222222222222222` -* and write the plaintext to "output.txt", - -run - - decrypt_file -a aes192 -m ofb -k 111111111111111111111111111111111111111111111111 -v 22222222222222222222222222222222 -i input.txt -o output.txt - -Bitmap encryption ------------------ - -These utilities were developed primarily to demonstrate the drawbacks of using -ECB mode (namely, the fact that identical plaintext blocks get mapped to -identical ciphertext blocks). -This can be explicitly shown using 8-bit-per-pixel bitmaps: - -| Plaintext BMP | Encrypted in ECB mode | Encrypted in CBC mode -| ---------------- | --------------------- | --------------------- -| ![butterfly.bmp] | ![cipherfly_ecb.bmp] | ![cipherfly_cbc.bmp] - -[butterfly.bmp]: bmp/butterfly.bmp -[cipherfly_ecb.bmp]: bmp/cipherfly_ecb.bmp -[cipherfly_cbc.bmp]: bmp/cipherfly_cbc.bmp - -### encrypt_bmp - -Encrypts the pixels in a BMP image file, preserving the header. -Otherwise, it's used the same way [encrypt_file](#encrypt_file) is. - -### decrypt_bmp - -Decrypts the pixels in a BMP image file, preserving the header. -Otherwise, it's used the same way [decrypt_file](#decrypt_file) is. - -See also --------- - -* [Usage on older CPUs] -* [License] - -[Usage on older CPUs]: ../README.md#usage-on-older-cpus -[License]: ../README.md#license |