Compiler that decrypts encrypted source code

• US 6,684,389 B1
• Filed: 08/05/1999
• Issued: 01/27/2004
• Est. Priority Date: 08/05/1999
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Wadsworth, Robert D., Uchida, Yoshiki, Lin, Denny M., Tanahashi, Junichi, Tanaka, Sadahiro
• Primary Examiner(s): ZHEN, WEI Y
• Application Number:
  US09/368,501
• Time in Patent Office: 1,636 Days
• Field of Search: 717/106,136,137,140-167,247,139 713/150-181,200 380/277-286,1
• US Class Current: 717/140
• CPC Class Codes: G06F 21/125 by manipulating the program code, e.g. source code, compiled code, interpreted code, machine code
• CPC Class Codes: G06F 21/14 against software analysis or reverse engineering, e.g. by obfuscation
• CPC Class Codes: G06F 8/41 Compilation

Abstract

A decrypting compiler that accepts encrypted source code from a software manufacturer, decrypts the encrypted source code into plain text that is not accessible outside the compiler, and compiles the decrypted source code into linkable binary objects. Because the decrypting compiler decrypts the encrypted source code such that the plain text is not accessible outside the compiler, trade secret and proprietary information from the source code is not easily learned by third-party software developers.

Claims

1. A decrypting compiler comprising:

a first input section for inputting encrypted source code;

a second input section for inputting plain text source code;

a decrypting section that decrypts the encrypted source code into plain text decrypted source code; and

a compiling section that compiles the plain text input by the second input section and the plain text source code decrypted by the decrypting section, so as to produce compiled code therefrom,

wherein the encrypted source code input by the first input section is produced by a software manufacturer, and wherein the plain text source code input by the second input section is produced by a third-party software developer different from the software manufacturer.

2. A decrypting compiler according to claim 1, wherein the encrypted source code comprises encrypted source code instructions.

3. A decrypting compiler according to claim 1, wherein the encrypted source code comprises encrypted source code header information.

4. A decrypting compiler according to claim 1, wherein the encrypted source code comprises encrypted macros.

5. A decrypting compiler according to claim 1, wherein the encrypted source code input by the first input section includes proprietary information.

6. A decrypting compiler according to claim 1, wherein the decrypting section decrypts the encrypted source code into plain text that is not accessible outside the compiler.

7. A decrypting compiler according to claim 6, wherein the decrypting section produces plain text using a proprietary single-key encryption/decryption algorithm.

8. A decrypting compiler according to claim 6, wherein the decrypting section produces plain text using a public key/private key encryption algorithm, with the private key being embedded in the decrypting compiler.

9. A decrypting compiler according to claim 1, further comprising a parameter input section for inputting a parameter for selective compilation of the decrypted plain text, wherein the compiling section is responsive to compiler directives keyed to the input parameter so as to selectively compile different sections of source code.

10. A decrypting compiler according to claim 9, wherein the input parameter comprises information of a number of processing clusters for a target system'"'"'s CPU, and wherein the compiled code is for a corresponding very long instruction word command set.

11. A decrypting compiler according to claim 9, wherein the input parameter comprises register partitioning information.

12. A decrypting compiler according to claim 9, wherein the input parameter comprises any information which characterizes a target system in a way which affects what code will execute on the target system.

13. A decrypting compiler according to claim 1, wherein the compiling section compiles the decrypted source code inline with the plain text source code.

14. A decrypting compiler according to claim 1, wherein the compiled code comprises linkable binary objects.

15. A decrypting compiler according to claim 1, wherein the compiled code comprises an executable object.

16. A system for generating an executable for a target device, comprising:

a first input section for inputting encrypted source code;

a second input section for inputting plain text source code;

a decrypting section that decrypts the encrypted source code into plain text decrypted source code;

a compiling section that compiles the plain text input by the second input section and the plain text source code decrypted by the decrypting section, so as to produce linkable binary objects; and

a linker that links the linkable binary objects produced by the compiling section so as to generate the executable,

wherein the encrypted source code input by the first input section is produced by a software manufacturer, and wherein the plain text source code input by the second input section is produced by a third-party software developer different from the software manufacturer.

17. An apparatus for compiling source code, comprising:

a memory including a region for storing executable process steps;

and a processor for executing the executable process steps, the executable process steps including;

(a) a first input step for inputting encrypted source code;

(b) a second input step for inputting plain text source code;

(c) a decrypting step that decrypts the encrypted source code into plain text decrypted source code; and

(d) a compiling step that compiles the plain text input by the second input step and the plain text source code decrypted by the decrypting step, so as to produce compiled code therefrom,

wherein the encrypted source code input by the first input step is produced by a software manufacturer, and wherein the plain text source code input by the second input step is produced by a third-party software developer different from the software manufacturer.

18. An apparatus according to claim 17, wherein the encrypted source code comprises encrypted source code instructions.

19. An apparatus according to claim 17, wherein the encrypted source code comprises encrypted source code header information.

20. An apparatus according to claim 17, wherein the encrypted source code comprises encrypted macros.

21. An apparatus according to claim 17, wherein the encrypted source code input by the first input step includes proprietary information.

22. An apparatus according to claim 17, wherein the decrypting step decrypts the encrypted source code into plain text that is not accessible outside the decrypting step and the compiling step.

23. An apparatus according to claim 22, wherein the decrypting step produces plain text using a proprietary single-key encryption/decryption algorithm.

24. An apparatus according to claim 22, wherein the decrypting step produces plain text using a public key/private key encryption algorithm, with the private key being embedded in the decrypting compiler.

25. An apparatus according to claim 17, wherein the executable process steps further comprise a parameter input step for inputting a parameter for selective compilation of the decrypted plain text, and wherein the compiler step is responsive to compiler directives keyed to the input parameter so as to selectively compile different sections of source code.

26. An apparatus according to claim 25, wherein the input parameter comprises information of a number of processing clusters for a target system'"'"'s CPU, and wherein the compiled code is for a corresponding very long instruction word command set.

27. An apparatus according to claim 25, wherein the input parameter comprises register partitioning information.

28. An apparatus according to claim 25, wherein the input parameter comprises any information which characterizes a target system in a way which affects what code will execute on the target system.

29. An apparatus according to claim 17, wherein the compiling step compiles the decrypted source code inline with the plain text source code.

30. An apparatus according to claim 17, wherein the compiled code comprises linkable binary objects.

31. An apparatus according to claim 17, wherein the compiled code comprises an executable object.

32. An apparatus for generating an executable for a target device, comprising:

a memory including a region for storing executable process steps; and

a processor for executing the executable process steps, the executable process steps including;

(a) a first input step for inputting encrypted source code;

(b) a second input step for inputting plain text source code;

(c) a decrypting step that decrypts the encrypted source code into plain text decrypted source code;

(d) a compiling step that compiles the plain text input by the second input step and the plain text source code decrypted by the decrypting step, so as to produce linkable binary objects; and

(e) a linking step that links the linkable binary objects produced by the compiling step so as to generate the executable,

wherein the encrypted source code input by the first input step is produced by a software manufacturer, and wherein the plain text source code input by the second input step is produced by a third-party software developer different from the software manufacturer.

33. Computer-executable process steps stored on a computer-readable medium, the computer executable process steps for compiling source code, the computer-executable process steps comprising:

first input code for inputting encrypted source code;

second input code for inputting plain text source code;

decrypting code that decrypts the encrypted source code into plain text decrypted source code; and

compiling code that compiles the plain text input by the second input code and the plain text source code decrypted by the decrypting code, so as to produce compiled code therefrom,

wherein the encrypted source code input by the first input code is produced by a software manufacturer, and wherein the plain text source code input by the second input code is produced by a third-party software developer different from the software manufacturer.

34. Computer-executable process steps according to claim 33, wherein the encrypted source code comprises encrypted source code instructions.

35. Computer-executable process steps according to claim 33, wherein the encrypted source code comprises encrypted source code header information.

36. Computer-executable process steps according to claim 33, wherein the encrypted source code comprises encrypted macros.

37. Computer-executable process steps according to claim 33, wherein the encrypted source code input by the first input code includes proprietary information.

38. Computer-executable process steps according to claim 33, wherein the decrypting code decrypts the encrypted source code into plain text that is not accessible outside the decrypting code and the compiling code.

39. Computer-executable process steps according to claim 38, wherein the decrypting code produces plain text using a proprietary single-key encryption/decryption algorithm.

40. Computer-executable process steps according to claim 38, wherein the decrypting code produces plain text using a public key/private key encryption algorithm, with the private key being embedded in the decrypting compiler.

41. Computer-executable process steps according to claim 33, wherein the executable process steps further comprise parameter input code for inputting a parameter for selective compilation of the decrypted plain text, and wherein the compiler code is responsive to compiler directives keyed to the input parameter so as to selectively compile different sections of source code.

42. Computer-executable process steps according to claim 41, wherein the input parameter comprises information of a number of processing clusters for a target system'"'"'s CPU, and wherein the compiled code is for a corresponding very long instruction word command set.

43. Computer-executable process steps according to claim 41, wherein the input parameter comprises register partitioning information.

44. Computer-executable process steps according to claim 41, wherein the input parameter comprises any information which characterizes a target system in a way which affects what code will execute on the target system.

45. Computer-executable process steps according to claim 33, wherein the compiling code compiles the decrypted source code inline with the plain text source code.

46. Computer-executable process steps according to claim 33, wherein the compiled code comprises linkable binary objects.

47. Computer-executable process steps according to claim 33, wherein the compiled code comprises an executable object.

48. Computer-executable process steps stored on a computer-readable medium, the computer executable process steps for generating an executable for a target device, the computer-executable process steps comprising:

first input code for inputting encrypted source code;

second input code for inputting plain text source code;

decrypting code that decrypts the encrypted source code into plain text decrypted source code;

compiling code that compiles the plain text input by the second input code and the plain text source code decrypted by the decrypting code, so as to produce linkable binary objects; and

linking code that links the linkable binary objects produced by the compiling code so as to generate the executable,

wherein the encrypted source code input by the first input code is produced by a software manufacturer, and wherein the plain text source code input by the second input code is produced by a third-party software developer different from the software manufacturer.

49. A computer-readable medium which stores computer-executable process steps, the computer-executable process steps for compiling source code, the computer-executable process steps comprising:

a first input step for inputting encrypted source code;

a second input step for inputting plain text source code;

a decrypting step that decrypts the encrypted source code into plain text decrypted source code; and

a compiling step that compiles the plain text input by the second input step and the plain text source code decrypted by the decrypting step, so as to produce compiled code therefrom,

wherein the encrypted source code input by the first input step is produced by a software manufacturer, and wherein the plain text source code input by the second input step is produced by a third-party software developer different from the software manufacturer.

50. A computer-readable medium according to claim 49, wherein the encrypted source code comprises encrypted source code instructions.

51. A computer-readable medium according to claim 49, wherein the encrypted source code comprises encrypted source code header information.

52. A computer-readable medium according to claim 49, wherein the encrypted source code comprises encrypted macros.

53. A computer-readable medium according to claim 49, wherein the encrypted source code input by the first input step includes proprietary information.

54. A computer-readable medium according to claim 49, wherein the decrypting step decrypts the encrypted source code into plain text that is not accessible outside the decrypting step and the compiling step.

55. A computer-readable medium according to claim 54, wherein the decrypting step produces plain text using a proprietary single-key encryption/decryption algorithm.

56. A computer-readable medium according to claim 54, wherein the decrypting step produces plain text using a public key/private key encryption algorithm, with the private key being embedded in the decrypting compiler.

57. A computer-readable medium according to claim 49, wherein the executable process steps further comprise a parameter input step for inputting a parameter for selective compilation of the decrypted plain text, and wherein the compiler step is responsive to compiler directives keyed to the input parameter so as to selectively compile different sections of source code.

58. A computer-readable medium according to claim 57, wherein the input parameter comprises information of a number of processing clusters for a target system'"'"'s CPU, and wherein the compiled code is for a corresponding very long instruction word command set.

59. A computer-readable medium according to claim 57, wherein the input parameter comprises register partitioning information.

60. A computer-readable medium according to claims 57, wherein the input parameter comprises any information which characterizes a target system in a way which affects what code will execute on the target system.

61. A computer-readable medium according to claim 49, wherein the compiling step compiles the decrypted source code inline with the plain text source code.

62. A computer-readable medium according to claim 49, wherein the compiled code comprises linkable binary objects.

63. A computer-readable medium according to claim 49, wherein the compiled code comprises an executable object.

64. A computer-readable medium which stores computer-executable process steps, the computer-executable process steps for generating an executable for a target device, the computer-executable process steps comprising:

a first input step for inputting encrypted source code;

a second input step for inputting plain text source code;

a decrypting step that decrypts the encrypted source code into plain text decrypted source code;

a compiling step that compiles the plain text input by the second input step and the plain text source code decrypted by the decrypting step, so as to produce linkable binary objects; and

a linking step that links the linkable binary objects produced by the compiling step so as to generate the executable,

wherein the encrypted source code input by the first input step is produced by a software manufacturer, and wherein the plain text source code input by the second input step is produced by a third-party software developer different from the software manufacturer.

65. An apparatus for compiling source code, comprising:

first input means for inputting encrypted source code;

second input means for inputting plain text source code;

decrypting means for decrypting the encrypted source code into plain text decrypted source code; and

compiling means for compiling the plain text input by the second input means and the plain text source code decrypted by the decrypting means, so as to produce compiled code therefrom,

wherein the encrypted source code input by the first input means is produced by a software manufacturer, and wherein the plain text source code input by the second input means is produced by a third-party software developer different from the software manufacturer.

66. An apparatus according to claim 65, wherein the encrypted source code comprises encrypted source code instructions.

67. An apparatus according to claim 65, wherein the encrypted source code comprises encrypted source code header information.

68. An apparatus according to claim 65, wherein the encrypted source code comprises encrypted macros.

69. An apparatus according to claim 65, wherein the encrypted source code input by the first input means includes proprietary information.

70. An apparatus according to claim 65, wherein the decrypting means decrypts the encrypted source code into plain text that is not accessible outside the decrypting means and the compiling means.

71. An apparatus according to claim 70, wherein the decrypting means produces plain text using a proprietary single-key encryption/decryption algorithm.

72. An apparatus according to claim 70, wherein the decrypting means produces plain text using a public key/private key encryption algorithm, with the private key being embedded in the decrypting compiler.

73. An apparatus according to claim 65, further comprising a parameter input means for inputting a parameter for selective compilation of the decrypted plain text, and wherein the compiler means is responsive to compiler directives keyed to the input parameter so as to selectively compile different sections of source code.

74. An apparatus according to claim 73, wherein the input parameter comprises information of a number of processing clusters for a target system'"'"'s CPU, and wherein the compiled code is for a corresponding very long instruction word command set.

75. An apparatus according to claim 73, wherein the input parameter comprises register partitioning information.

76. An apparatus according to claim 73, wherein the input parameter comprises any information which characterizes a target system in a way which affects what code will execute on the target system.

77. An apparatus according to claim 65, wherein the compiling means compiles the decrypted source code inline with the plain text source code.

78. An apparatus according to claim 65, wherein the compiled code comprises linkable binary objects.

79. An apparatus according to claim 65, wherein the compiled code comprises an executable object.

80. An apparatus for generating an executable for a target device, comprising:

first input means for inputting encrypted source code;

second input means for inputting plain text source code;

decrypting means for decrypting the encrypted source code into plain text decrypted source code;

compiling means for compiling the plain text input by the second input means and the plain text source code decrypted by the decrypting means, so as to produce linkable binary objects; and

linking means for linking the linkable binary objects produced by the compiling means so as to generate the executable,

wherein the encrypted source code input by the first input means is produced by a software manufacturer, and wherein the plain text source code input by the second input means is produced by a third-party software developer different from the software manufacturer.

81. A decrypting compiler comprising:

a first input section for inputting encrypted source code;

a second input section for inputting plain text source code;

a decrypting section that decrypts the encrypted source code into plain text decrypted source code; and

a compiling section that compiles the plain text input by the second input section and the plain text source code decrypted by the decrypting section, so as to produce compiled code therefrom,

wherein the encrypted source code input by the first input section is produced by a first provider, and wherein the plain text source code input by the second input section is produced by a second provider different from the first provider.

82. Computer-executable process steps stored on a computer-readable medium, the computer executable process steps for compiling source code, the computer-executable process steps comprising:

first input code for inputting encrypted source code;

second input code for inputting plain text source code;

decrypting code that decrypts the encrypted source code into plain text decrypted source code; and

compiling code that compiles the plain text input by the second input code and the plain text source code decrypted by the decrypting code, so as to produce compiled code therefrom,

wherein the encrypted source code input by the first input code is produced by a first provider, and wherein the plain text source code input by the second input code is produced by a second provider different from the first provider.