Document signing system for mobile devices

1. A system, comprising:

a computing device comprising a processor and a memory;

machine-readable instructions stored in the memory that, when executed by the processor, cause the computing device to at least:

send a request to a certificate authority for a signing certificate;

receive the signing certificate from the certificate authority, the signing certificate being encrypted using an authentication certificate;

store the signing certificate in the memory;

receive a file from a client application executed by the processor of the computing device;

verify that a first authentication credential from the client application matches a second authentication credential associated with the signing certificate;

decrypt the signing certificate using the first authentication credential;

in an instance in which the first authentication credential matches the second authentication credential, sign the file with the signing certificate to create a signed file;

insert information used to generate a cryptographic signature for the file into the signed file, the information comprising a fingerprint of the signing certificate; and

return the signed file to the client application.

2. The system of claim 1 , wherein the machine readable instructions further cause the computing device to at least:

request the first authentication credential from the client application in response to receipt of the file;

receive the first authentication credential from the client application; and

wherein the machine readable instructions cause the computing device to sign the file with the signing certificate in response to a verification that the first authentication credential matches the second authentication credential.

3. The system of claim 2 , wherein the signing certificate is encrypted using the authentication certificate according to a version of a Public-Key Cryptography (PKCS) standard.

4. The system of claim 2 , wherein the first authentication credential is a password.

5. The system of claim 1 , wherein the machine readable instructions further cause the computing device to at least:

determine that the signing certificate is absent from the memory of the computing device; and

the request to the certificate authority is sent in response to a determination that the signing certificate is absent from the memory of the computing device.

6. The system of claim 1 , wherein the machine readable instructions further cause the computing device to at least:

convert the file from a first file type into a second file type; and

the file is signed to generate the signed file in response to a conversion of the file from the first file type into the second file type.

7. The system of claim 1 , wherein the signing certificate is derived from a user account credential.

8. A method, comprising:

sending, by a computing device, a request to a certificate authority for a signing certificate;

receiving, by the computing device, the signing certificate from the certificate authority, the signing certificate being encrypted using an authentication certificate;

storing, by the computing device, the signing certificate in a memory of the computing device;

receiving, by the computing device, a file from a client application executed by a processor of the computing device;

verifying, by the computing device, that a first authentication credential from the client application matches a second authentication credential associated with the signing certificate;

decrypting, by the computing device, the signing certificate using the first authentication credential;

in an instance in which the first authentication credential matches the second authentication credential, signing, by the computing device, the file with the signing certificate to create a signed file;

inserting, by the computing device, information used to generate a cryptographic signature for the file into the signed file, the information comprising a fingerprint of the signing certificate; and

returning, by the computing device, the signed file to the client application.

9. The method of claim 8 , further comprising:

requesting, by the computing device, the first authentication credential from the client application in response to receipt of the file;

receiving, by the computing device, the first authentication credential from the client application; and

wherein signing the file with the signing certificate occurs in response to verifying that the first authentication credential matches the second authentication credential.

10. The method of claim 9 , wherein the signing certificate is encrypted using the authentication certificate according to a version of a Public-Key Cryptography (PKCS) standard.

11. The method of claim 9 , wherein the first authentication credential is a password.

12. The method of claim 8 , further comprising:

determining, by the computing device, that the signing certificate is absent from the memory of the computing device; and

the request to the certificate authority is sent in response to determining that the signing certificate is absent from the memory of the computing device.

13. The method of claim 8 , further comprising:

converting, by the computing device, the file from a first file type into a second file type; and

the file is signed to generate the signed file in response to converting the file from the first file type into the second file type.

14. The method of claim 8 , wherein the signing certificate is derived from a user account credential.

15. A non-transitory, computer-readable medium comprising machine-readable instructions that, when executed by a processor of a computing device, cause the computing device to at least:

send a request to a certificate authority for a signing certificate;

receive the signing certificate from the certificate authority, the signing certificate being encrypted using an authentication certificate;

store the signing certificate in a memory of the computing device;

receive a file from a client application executed by the processor of the computing device;

verify that a first authentication credential from the client application matches a second authentication credential associated with the signing certificate;

decrypt the signing certificate using the first authentication credential;

in an instance in which the first authentication credential matches the second authentication credential, sign the file with the signing certificate to create a signed file;

insert information used to generate a cryptographic signature for the file into the signed file, the information comprising a fingerprint of the signing certificate; and

return the signed file to the client application.

16. The non-transitory, computer-readable medium of claim 15 , wherein the machine readable instructions further cause the computing device to at least:

request the first authentication credential from the client application in response to receipt of the file;

receive the first authentication credential from the client application; and

wherein the machine readable instructions cause the computing device to sign the file with the signing certificate in response to a verification that the first authentication credential matches the second authentication credential.

17. The non-transitory, computer-readable medium of claim 16 , wherein the signing certificate is encrypted using the authentication certificate according to a version of a Public-Key Cryptography (PKCS) standard.

18. The non-transitory, computer-readable medium of claim 16 , wherein the first authentication credential is a password.

19. The non-transitory, computer-readable medium of claim 15 , wherein the machine readable instructions further cause the computing device to at least:

determine that the signing certificate is absent from the memory of the computing device; and

the request to the certificate authority is sent in response to a determination that the signing certificate is absent from the memory of the computing device.

20. The non-transitory, computer-readable medium of claim 15 , wherein the machine readable instructions further cause the computing device to at least:

convert the file from a first file type into a second file type; and

the file is signed to generate the signed file in response to a conversion of the file from the first file type into the second file type.