Protection of digital content using block cipher crytography
View Patent ↗Protection of digital content using a specific application of block cipher cryptography is described. The digital content is encrypted using an encryption key and a calculated initialization vector. The digital content includes a plurality of strides of data and each stride includes a string of data to be encrypted and a block of data to be encrypted. The calculated initialization vector to be used to encrypt the block of data is derived from the string of data in the stride to be encrypted. Furthermore, the initialization vector is calculated by performing an exclusive disjunction function on a seed value and the string of data for each stride.
1. A computerized method comprising:
encrypting digital content using an encryption key and a calculated initialization vector (IV), wherein the digital content comprises a plurality of strides, each stride comprising a string of data to be encrypted and a block of data, and wherein the calculated IV comprises information from the strings of data in the strides.
2. The computerized method of claim 1 , wherein the calculated IV is further derived from each string of data and a seed value using an exclusive disjunction (XOR) function.
3. The computerized method of claim 1 , wherein the calculated IV is further derived from each string of data using an exclusive disjunction (XOR) function.
4. The computerized method of claim 1 , wherein each string of data is encrypted using an advance encryption standard cipher with an electronic codebook mode.
5. The computerized method of claim 1 , wherein each block of data is encrypted using an advance encryption standard cipher with a cipher block chaining mode.
6. The computerized method of claim 1 , wherein each string of data comprises a pre-determined number of bytes of a stride of an access unit.
7. The computerized method of claim 1 , wherein the digital content is a digital music file or a digital video file.
8. A computerized method comprising:
calculating an initialization vector for encrypting data using a block cipher, wherein the data comprises a plurality of strides, each stride comprising a string of data and a block of data, and the initialization vector comprises information from the strings of data in the strides.
9. The computerized method of claim 8 , wherein the calculating further comprises:
performing an exclusive disjunction (XOR) function on each string of data.
10. The computerized method of claim 8 , wherein the calculating further comprises:
performing an exclusive disjunction (XOR) function on a seed value and each string of data.
11. The computerized method of claim 8 , wherein the data is a digital content file.
12. A machine-readable medium having instructions to cause a machine to perform a method, the method comprising:
encrypting digital content using an encryption key and a calculated initialization vector (IV), wherein the digital content comprises a plurality of strides, each stride comprising a string of data to be encrypted and a block of data, and the calculated IV comprises information from the strings of data in the strides.
13. The machine-readable medium of claim 12 , wherein the calculated IV is further derived from each string of data and a seed value using an exclusive disjunction (XOR) function.
14. The machine-readable medium of claim 12 , wherein the calculated IV is further derived from each string of data using an exclusive disjunction (XOR) function.
15. The machine-readable medium of claim 12 , wherein each string of data is encrypted using an advance encryption standard cipher with an electronic codebook mode.
16. The machine-readable medium of claim 12 , wherein each block of data is encrypted using an advance encryption standard cipher with a cipher block chaining mode.
17. The machine-readable medium of claim 12 , wherein each string of data comprises a pre-determined number of bytes of a stride of an access unit.
18. The machine-readable medium of claim 12 , wherein the digital content is a digital music file or a digital video file.
19. A machine-readable medium having instructions to cause a machine to perform a method, the method comprising:
calculating an initialization vector for encrypting data using a block cipher, wherein the data comprises a plurality of strides, each stride comprising a string of data and a block of data, and the initialization vector comprises information from the strings of data in the strides.
20. The machine-readable medium of claim 19 , wherein the calculating further comprises:
performing an exclusive disjunction (XOR) function on each string of data.
21. The machine-readable medium of claim 19 , wherein the calculating further comprises:
performing an exclusive disjunction (XOR) function on a seed value and each string of data.
22. The machine-readable medium of claim 19 , wherein the data is a digital content file.
23. A system comprising:
a processor coupled to a memory through a bus; and
an encryption process executed by the processor from the memory to cause the processor to encrypt digital content using an encryption key and a calculated initialization vector (IV), wherein the digital content comprises a plurality of strides, each stride comprising a string of data to be encrypted and a block of data, and wherein the calculated IV comprises information from the strings of data in the strides.
24. The system of claim 23 , wherein the calculated IV is derived from each string of data using an exclusive disjunction (XOR) function.
25. The system of claim 23 , wherein the calculated IV is derived from each string of data and a seed value using an exclusive disjunction (XOR) function.
26. The system of claim 23 , wherein each string of data is encrypted using an advance encryption standard cipher with an electronic codebook mode.
27. The system of claim 23 , wherein each block of data is encrypted using an advance encryption standard with a cipher block chaining mode.
28. The system of claim 23 , wherein each string of data comprises a first pre-determined number of bytes of a stride of an access unit.
29. The system of claim 23 , wherein the digital content is a digital music file or a digital video file.
30. A system comprising:
a processor coupled to a memory through a bus; and
an encryption process executed by the processor from the memory to cause the processor to calculate an initialization vector for encrypting data using a block cipher, wherein the data comprises a plurality of strides, each stride comprising a string of data and a block of data, and the initialization vector comprises information from the strings of data in the strides.
31. The system of claim 30 , wherein the encryption process further causes the processor, when calculating the initialization vector, to perform an exclusive disjunction (XOR) function on each string of data.
32. The system of claim 30 , wherein the encryption process further causes the processor, when the calculating the initialization vector, to perform an exclusive disjunction (XOR) function on a seed value and each string of data.
33. The system of claim 30 , wherein the data is a digital content file.
34. An apparatus comprising:
means for receiving digital content; and
means for encrypting the digital content using an encryption key and a calculated initialization vector (IV), wherein the digital content comprises a plurality of strides, each stride comprising a string of data to be encrypted and a block of data, and wherein the calculated IV comprises information from the strings of data in the strides.
35. The apparatus of claim 34 , wherein the calculated IV is derived from each string of data using an exclusive disjunction (XOR) function.
36. The apparatus of claim 34 , wherein the calculated IV is derived from each string of data and a seed value using an exclusive disjunction (XOR) function.
37. The apparatus of claim 34 , wherein each string of data is encrypted using an advance encryption standard cipher with an electronic codebook mode.
38. The apparatus of claim 34 , wherein each block of data is encrypted using an advance encryption standard with a cipher block chaining mode.
39. The apparatus of claim 34 , wherein each string of data comprises a first pre-determined number of bytes of a stride of an access unit.
40. The apparatus of claim 34 , wherein the digital content is a digital music file or a digital video file.
41. A apparatus comprising:
means for receiving data; and
means for calculating an initialization vector for encrypting the data using a block cipher, wherein the data comprises a plurality of strides, each stride comprising a string of data and a block of data, and the initialization vector comprises information from the strings of data in the strides.
42. The apparatus of claim 41 , wherein the means for calculating further comprises:
a means for performing an exclusive disjunction (XOR) function on each string of data.
43. The apparatus of claim 41 , wherein the means for calculating further comprises:
a means for performing an exclusive disjunction (XOR) function on a seed value and each string of data.
44. The apparatus of claim 41 , wherein the data is a digital content file.