Apparatus and method for cryptographic operations using enhanced knowledge factor credentials

1. A method, comprising:

obtaining, with a computing device, a multi-byte character set specifying a plurality of characters;

receiving, with the computing device, a knowledge factor credential encoded with a plurality of characters of the multi-byte character set, wherein the knowledge factor credential has a longer effective length than an apparent length, and wherein the knowledge factor credential has at least one character outside of a block of characters designated for a locale of the computing device, wherein receiving the knowledge factor credential comprises:

retrieving from memory candidate characters based on a user previously designating the candidate characters;

presenting a user interface by which the candidate characters are selectable, wherein presenting a user interface by which the candidate characters are selectable comprises interspersing the candidate characters among un-designated characters to obfuscate which characters were previously designated;

receiving a user selection of at least one of the candidate characters; and

providing, with the computing device, the knowledge factor credential to authenticate a user.

2. The method of claim 1 , wherein:

the multi-byte character set specifying a plurality of characters is a Unicode character set specifying more than 32,000 characters;

receiving a knowledge factor credential comprises:

displaying a user interface by which a user is presented more than 32,000 user-selectable characters of the Unicode character set; and

receiving at least one character of the knowledge factor credential via the user interface,

wherein at least one character of the knowledge factor credential combines a plurality of constituent characters into a single character with code points;

providing the knowledge factor credential comprises:

transforming the knowledge factor credential into an authentication token; and

creating an authentication digest based on the authentication token and at least one other parameter;

the method further comprises:

comparing the authentication digest to a previously stored authentication digest to authenticate the user.

3. The method of claim 1 , wherein receiving the knowledge factor credential comprises:

presenting a user interface through which more than 256 characters are selectable; and

receiving a user selection of at least one of the more than 256 characters.

4. The method of claim 1 , wherein receiving the knowledge factor credential comprises:

presenting a user interface through which more than 1,024 characters are selectable.

5. The method of claim 1 , wherein receiving the knowledge factor credential comprises:

presenting a user interface through which more than 4,096 characters are selectable.

6. The method of claim 1 , wherein receiving the knowledge factor credential comprises:

presenting a user interface through which more than 32,768 characters are selectable.

7. The method of claim 1 , wherein receiving the knowledge factor credential comprises:

presenting a user interface by which a single composite character is composed by selecting a plurality of constituent characters;

receiving user selections of the constituent characters; and

combining the constituent characters into a single character with a plurality of code points, wherein the single character is at least one composite character of the knowledge factor credential.

8. The method of claim 1 , wherein providing the knowledge factor credential to authenticate a user comprises:

normalizing the characters of the credential by changing a sequence of bits with which at least one of the characters in the credential is encoded.

9. The method of claim 1 , wherein providing the knowledge factor credential to authenticate a user comprises:

including a byte order mark to a sequence of bytes encoding the knowledge factor credential; and

sequencing the bytes encoding knowledge factor credential consistent with the byte order mark.

10. The method of claim 1 , wherein providing the knowledge factor credential to authenticate a user comprises:

submitting the knowledge factor credential via an un-lock screen or a login screen of an operating system executed by the computing device.

11. The method of claim 1 , wherein the multi-byte character set comprises more than 100,000 characters.

12. The method of claim 1 , wherein the multi-byte character set comprises a Unicode character set.

13. The method of claim 1 , wherein the knowledge factor credential comprises an emoji character.

14. The method of claim 1 , wherein the knowledge factor credential comprises a user-composed character comprising multiple, user-selected constituent characters in a single apparent character.

15. A tangible, non-transitory, machine-readable medium storing instructions that when executed by one or more processors effectuate operations comprising:

obtaining a multi-byte character set specifying a plurality of characters;

receiving a knowledge factor credential encoded with a plurality of characters of the multi-byte character set, wherein the knowledge factor credential has a longer effective length than an apparent length, and wherein the knowledge factor credential has at least one character outside of a block of characters designated for a locale of the computing device, wherein receiving the knowledge factor credential comprises:

retrieving from memory candidate characters based on a user previously designating the candidate characters;

presenting a user interface by which the candidate characters are selectable, wherein presenting a user interface by which the candidate characters are selectable comprises interspersing the candidate characters among un-designated characters to obfuscate which characters were previously designated;

receiving a user selection of at least one of the candidate characters; and

providing the knowledge factor credential to authenticate a user.

16. The medium of claim 15 , wherein:

the multi-byte character set specifying a plurality of characters is a Unicode character set specifying more than 32,000 characters;

receiving a knowledge factor credential comprises:

displaying a user interface by which a user is presented more than 32,000 user-selectable characters of the Unicode character set; and

receiving at least one character of the knowledge factor credential via the user interface,

wherein at least one character of the knowledge factor credential combines a plurality of constituent characters into a single character with a plurality of code points;

providing the knowledge factor credential comprises:

transforming the knowledge factor credential into an authentication token; and

creating an authentication digest based on the authentication token and at least one other parameter;

the method further comprises:

comparing the authentication digest to a previously stored authentication digest to authenticate the user.

17. The medium of claim 15 , wherein receiving the knowledge factor credential comprises:

presenting a user interface through which more than 256 characters are selectable; and

receiving a user selection of at least one of the more than 256 characters.

18. The medium of claim 15 , wherein receiving the knowledge factor credential comprises:

presenting a user interface through which more than 1,024 characters are selectable.

19. The medium of claim 15 , wherein receiving the knowledge factor credential comprises:

presenting a user interface through which more than 4,096 characters are selectable.

20. The medium of claim 15 , wherein receiving the knowledge factor credential comprises:

presenting a user interface by which a single composite character is composed by selecting a plurality of constituent characters;

receiving user selections of the constituent characters; and

combining the constituent characters into a single character with a plurality of code points, wherein the single character is at least one composite character of the knowledge factor credential.

21. The medium of claim 15 , wherein providing the knowledge factor credential to authenticate a user comprises:

normalizing the characters of the credential by changing a sequence of bits with which at least one of the characters in the credential is encoded.

22. The medium of claim 15 , wherein providing the knowledge factor credential to authenticate a user comprises:

including a byte order mark to a sequence of bytes encoding the knowledge factor credential; and

sequencing the bytes encoding knowledge factor credential consistent with the byte order mark.

23. The medium of claim 15 , wherein providing the knowledge factor credential to authenticate a user comprises:

submitting the knowledge factor credential via an un-lock screen or a login screen of an operating system executed by the computing device.

24. The medium of claim 15 , wherein the multi-byte character set comprises a Unicode character set.

25. The medium of claim 15 , wherein the knowledge factor credential comprises an emoji character.

26. The medium of claim 15 , wherein the knowledge factor credential comprises a user-composed character comprising multiple, user-selected constituent characters in a single apparent character.