Bài tập-des
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The document provides the input block, key, and instructions to perform two rounds of DES encryption to find the output ciphertext. It gives the input block, key K, and shows the results of the first round of left-right shifts and permutation-choice 1. It then provides permutation-choice 2 to be XORed with the results of the first round to give the final ciphertext.
Bài tập-des
- 1. Bài tập tổng hợp về mã hóa DES Cho bảng dữ liệu và khóa K như bên dưới, tìm bản tin đầu ra sau khi lặp 2 vòng. 1 1 1 0 1 1 0 0 1 0 0 0 0 1 1 1 0 1 0 1 0 1 0 1 1 1 1 0 1 0 0 1 1 0 1 0 1 1 0 0 0 1 1 1 0 1 1 0 0 1 0 0 0 0 1 0 1 0 1 1 1 1 0 0 Khối dữ liệu đầu vào 0 0 1 0 1 1 0 0 1 0 1 0 0 1 1 1 0 1 0 1 0 1 0 0 0 1 1 1 1 0 0 1 1 0 1 0 1 1 0 1 1 0 1 1 0 1 1 0 1 1 0 0 1 0 1 1 1 0 1 0 1 0 0 0 Khóa K
- 2. 0 1 1 0 1 1 0 1 1 0 1 0 0 1 0 0 1 0 1 1 0 1 1 1 0 0 0 0 1 1 1 0 1 0 0 1 1 0 1 1 1 0 1 1 1 0 0 1 1 0 0 1 1 0 0 1 0 1 1 0 0 0 1 0 0 1 1 0 1 1 0 1 1 0 1 0 0 1 0 0 1 0 1 1 0 1 1 1 0 0 0 0 1 1 1 0 1 0 0 1 1 0 1 1 1 0 1 1 1 0 0 1 1 0 0 1 1 0 0 1 0 1 1 0 0 0 1 0 L 0 R 0
- 3. 0 1 0 0 1 1 1 1 0 1 1 1 1 1 0 1 1 1 1 1 0 0 1 1 1 1 0 0 1 1 1 1 0 0 1 0 1 0 1 0 0 0 0 0 0 1 0 1 E table
- 4. 0 0 1 0 1 1 0 0 1 0 1 0 0 1 1 1 0 1 0 1 0 1 0 0 0 1 1 1 1 0 0 1 1 0 1 0 1 1 0 1 1 0 1 1 0 1 1 0 1 1 0 0 1 0 1 1 1 0 1 0 1 0 0 0 1 2 3 4 5 6 7 8 9 17 25 33 41 49 57 1 1 1 1 0 0 1 0 0 1 0 0 1 1 0 0 1 0 1 1 1 0 1 1 0 0 1 0 0 1 1 0 0 0 1 0 0 0 1 1 0 1 1 1 1 1 0 1 1 0 0 1 1 1 0 0
- 5. 1 1 1 1 0 0 1 0 0 1 0 0 1 1 0 0 1 0 1 1 1 0 1 1 0 0 1 0 Left 0 1 1 0 0 0 1 0 0 0 1 1 0 1 1 1 1 1 0 1 1 0 0 1 1 1 0 0 right PC-1
- 6. 1 1 1 0 0 1 0 0 1 0 0 1 1 0 0 1 0 1 1 1 0 1 1 0 0 1 0 1 1 1 0 0 0 1 0 0 0 1 1 0 1 1 1 1 1 0 1 1 0 0 1 1 1 0 0 0 Left-right sau dịch vòng trái lần 1
- 7. 1 1 1 0 0 1 0 0 1 0 0 1 1 0 0 1 0 1 1 1 0 1 1 0 0 1 0 1 1 1 0 0 0 1 0 0 0 1 1 0 1 1 1 1 1 0 1 1 0 0 1 1 1 0 0 0 0 0 0 0 1 0 1 1 0 1 0 0 1 1 1 0 1 0 1 0 0 1 1 1 1 1 0 0 1 0 1 0 1 1 0 1 1 0 1 0 1 1 0 1 0 0 1 0 1 2 3 4 5 6 7 8 15 22 29 36 43 50 Pc-2 : K1
- 8. 0 1 0 0 1 1 1 1 0 1 1 1 1 1 0 1 1 1 1 1 0 0 1 1 1 1 0 0 1 1 1 1 0 0 1 0 1 0 1 0 0 0 0 0 0 1 0 1 0 0 0 0 1 0 1 1 0 1 0 0 1 1 1 0 1 0 1 0 0 1 1 1 1 1 0 0 1 0 1 0 1 1 0 1 1 0 1 0 1 1 0 1 0 0 1 0 0 1 0 0 0 1 0 0 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 0 0 0 0 0 0 1 0 1 1 1 1 1 0 0 0 0 1 1 0 1 0 1 1 1 XOR =
- 9. 0 1 0 0 0 1 0 0 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 0 0 0 0 0 0 1 0 1 1 1 1 1 0 0 0 0 1 1 0 1 0 1 1 1 C1 = 1010 C2 = 1101 C3 = 0110 C4 = 1000 C5 = 0010 C6 = 1000 C7 = 0000 C8 = 1011