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US6160891A Expired / Lapsed US ⏱️ 0.0 years remaining

Methods and apparatus for recovering keys

Assignee: Oracle America Inc
•
Filing: 1997-10-20
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Granted: 2000-12-12
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Expires: 2017-10-20
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Abstract

Abstract A key such as a private key or key password of a private key is encrypted for storage, and may be decrypted if the private key becomes lost or unavailable. The key is encrypted by encoding, for example, by hashing, private information such as mother's maiden name and social security number, and the result is used as a key to encrypt the private key using DES or another symmetric encryption technique. The encrypted key is again encrypted, for example using asymmetric encryption, using the public key of a trusted party such as the certificate authority that generated the private key. The result may be stored as a key recovery file by the principal of the private key or another party. To decrypt the key recovery file, the private key corresponding to the public key used to encrypt the key recovery file is used to decrypt the key recovery file, for example by asymmetric decryption. The result is symmetrically decrypted using a key obtained by encoding, for example, by hashing, the private information in the same manner as was used to encrypt the key. The result of this decryption is the key.

Inventors

  • 👤 Yahya Y Al-Salqan

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 23:00
CPC Classifications
H; H04; H04L; H04L9/00; H04L9/08; H04L9/0816; H04L9/0819; H04L9/0825; H04L9/06; H04L9/0643; H04L9/0894

Claims Analysis

Total Claims: 37
Claim 1
Independent Claim 220 words
A system for decrypting a key recovery file comprising an encrypted first key, the system comprising: a first decryptor, having a first input operatively coupled to receive at least a portion of the key recovery file and a second input operatively coupled to receive a second key, the first decryptor for decrypting at least a portion of the portion of the key recovery file received responsive to the second key received to produce a first decrypted first key and for providing at an output the first decrypted first key; a private information encoder having an input operatively coupled to receive a first set of private information, the private information encoder for encoding the first set of private information to produce encoded private information and for providing at an output the encoded private information; and a second decryptor having a first input coupled to the first decryptor output for receiving the first decrypted first key and a second input coupled to the private information encoder output for receiving the encoded private information, the second decryptor for decrypting the first decrypted first key received at the second decryptor first input responsive to the encoded private information received at the second decryptor second input to produce the first key and for providing the first key at an output coupled to a system output.
Claim 2
Independent Claim 220 words
A system for decrypting a key recovery file comprising an encrypted first key, the system comprising: a first decryptor, having a first input operatively coupled to receive at least a portion of the key recovery file and a second input operatively coupled to receive a second key, the first decryptor for decrypting at least a portion of the portion of the key recovery file received responsive to the second key received to produce a first decrypted first key and for providing at an output the first decrypted first key; a private information encoder having an input operatively coupled to receive a first set of private information, the private information encoder for encoding the first set of private information to produce encoded private information and for providing at an output the encoded private information; and a second decryptor having a first input coupled to the first decryptor output for receiving the first decrypted first key and a second input coupled to the private information encoder output for receiving the encoded private information, the second decryptor for decrypting the first decrypted first key received at the second decryptor first input responsive to the encoded private information received at the second decryptor second input to produce the first key and for providing the first key at an output coupled to a system output.
Claim 3
Dependent Claim 54 words
The system of claim 1 additionally comprising: a private information storage for storing a second set of private information, and for providing at an output coupled to the private information encoder input at least a portion of the second set of the private information stored responsive to a first index received at an input.
Claim 4
Dependent Claim 151 words
The system of claim 2, additionally comprising a private information compare having a first input coupled to the private information storage output for receiving the portion of the second set of private information and a second input operatively coupled to receive a third set of private information, the private information compare for comparing the portion of the second set of private information received at the private information compare first input and the third set of private information received at the private information compare second input and providing at an output coupled to the private information encoder input one selected from the portion of the second set of private information and the third set of private information responsive to the portion of the second set of private information received at the private information compare first input equivalent to the third set of private information received at the private information compare second input.
Claim 5
Dependent Claim 53 words
The system of claim 3 wherein the private information compare comprises an override input having a first state and a second state and the private information compare additionally provides at the private information compare output the portion of the second set of private information responsive to the override input in the first state.
Claim 6
Dependent Claim 47 words
The system of claim 2, wherein: the first key is one selected from a key password of a private key and a private key; the first index is a public key; and the private key is capable of use for decrypting information encrypted using the public key.
Claim 7
Dependent Claim 77 words
The system of claim 1 wherein: the private information encoder comprises a hasher having an input coupled to the private information encoder input to receive at least a portion of the private information, the hasher for hashing the private information received at the hasher input to produce hashed private information, and for providing the hashed private information at an output coupled to the private information encoder output; and the encoded private information comprises the hashed private information.
Claim 8
Dependent Claim 70 words
The system of claim 6, wherein the hasher comprises a SHA-1 hasher having an input coupled to the hasher input to receive at least a portion of the private information, the SHA-1 hasher for SHA-1-hashing the private information received at the SHA-1 hasher input to produce and provide at an output coupled to the hasher output the SHA-1-hashed private information; and the encoded private information comprises the SHA-1-hashed private information.
Claim 9
Dependent Claim 70 words
The system of claim 6, wherein the hasher comprises a MD-5 hasher having an input coupled to the hasher input to receive at least a portion of the private information, the MD-5 hasher for MD-5-hashing the private information received at the MD-5 hasher input to produce and provide at an output coupled to the hasher output the MD-5-hashed private information; and the encoded private information comprises the MD-5-hashed private information.
Claim 10
Dependent Claim 111 words
The system of claim 1 wherein: the second decryptor comprises a DES decryptor having a first input coupled to the second decryptor first input for receiving the first decrypted first key, a second input coupled to the second decryptor second input for receiving the encoded private information, the DES decryptor for DES decrypting the first decrypted first key received at the DES decryptor second input responsive to the encoded private information received at the DES decryptor second input to produce a DES-decrypted first key, and for providing at an output coupled to the second decryptor output the DES-decrypted first key; and the first decrypted first key comprises the DES-decrypted first key.
Claim 11
Dependent Claim 13 words
The system of claim 1 wherein the second key is a private key.
Claim 12
Dependent Claim 46 words
The system of claim 10 wherein: the first key is one selected from a key password of a private key generated by a certificate authority and a private key generated by a certificate authority; and the second key is a private key of the certificate authority.
Claim 13
Dependent Claim 98 words
The system of claim 1 wherein: the first decryptor comprises an asymmetric decryptor having a first input coupled to the first decryptor first input to receive at least a portion of the key recovery file and a second input coupled to the first decryptor second input to receive the second key, the asymmetric decryptor for asymmetrically decrypting the key recovery file responsive to the second key to produce an asymmetrically decrypted key recovery file, and for providing at the output the asymmetrically decrypted key recovery file; and the first decrypted first key comprises the asymmetrically decrypted first key.
Claim 14
Independent Claim 87 words
A method of decrypting a key recovery file comprising an encrypted first key, the method comprising: receiving at least a portion of the key recovery file; receiving a second key; using a first decryptor, decrypting the portion of the key recovery file received responsive to the second key received; receiving a first set of private information; encoding the first set of private information received; and using a second decryptor, and responsive to the first set of private information encoded, decrypting the portion of the key recovery file.
Claim 15
Independent Claim 87 words
A method of decrypting a key recovery file comprising an encrypted first key, the method comprising: receiving at least a portion of the key recovery file; receiving a second key; using a first decryptor, decrypting the portion of the key recovery file received responsive to the second key received; receiving a first set of private information; encoding the first set of private information received; and using a second decryptor, and responsive to the first set of private information encoded, decrypting the portion of the key recovery file.
Claim 16
Dependent Claim 28 words
The method of claim 13 wherein the receiving private information step comprises: providing an index; and receiving the first set of private information responsive to the index provided.
Claim 17
Dependent Claim 36 words
The method of claim 14, wherein: the receiving private information step additionally comprises receiving an index; the index provided comprises at least a portion of the index received; and the index received comprises a public key.
Claim 18
Dependent Claim 76 words
The method of claim 14 additionally comprising the steps of: receiving a second set of private information; comparing the first set of private information received with the second set of private information received; and wherein the encoding step and the step of decrypting the key recovery file responsive to the first set of private information encoded are responsive to the first set of private information received being equivalent to the second set of private information received.
Claim 19
Dependent Claim 22 words
The method of claim 13 wherein the encoding step comprises hashing the first set of private information received using a hash function.
Claim 20
Dependent Claim 16 words
The method of claim 17 wherein the hash function is one selected from SHA-1 and MD-5.
Claim 21
Dependent Claim 29 words
The method of claim 13, wherein the decrypting step comprises DES decrypting the key recovery file decrypted using the encoded first set of private information as a decryption key.
Claim 22
Dependent Claim 27 words
The method of claim 13, wherein decrypting the key recovery file comprises asymmetrically decrypting the key recovery file using the second key received as a decryption key.
Claim 23
Dependent Claim 13 words
The method of claim 13, wherein the second key is a private key.
Claim 24
Dependent Claim 49 words
The method of claim 21 wherein: the encrypted first key is produced from one selected from a key password of a first private key generated by a certificate authority and a first private key generated by a certificate authority; and the second key comprises a certificate authority private key.
Claim 25
Dependent Claim 17 words
The method of claim 13 wherein the first decryptor and the second decryptor are the same decryptor.
Claim 26
Dependent Claim 168 words
A computer program product comprising a computer useable medium having computer readable program code embodied therein for decrypting a key recovery file comprising an encrypted first key, the computer program product comprising: computer readable program code devices configured to cause a computer to receive at least a portion of the key recovery file; computer readable program code devices configured to cause a computer to receive a second key; computer readable program code devices configured to cause a computer using a first decryptor to decrypt the portion of the key recovery file received responsive to the second key received; computer readable program code devices configured to cause a computer to receive a first set of private information; computer readable program code devices configured to cause a computer to encode the first set of private information received; and computer readable program code devices configured to cause a computer using a second decryptor to, responsive to the first set of private information encoded, decrypt the portion of the key recovery file.
Claim 27
Dependent Claim 168 words
A computer program product comprising a computer useable medium having computer readable program code embodied therein for decrypting a key recovery file comprising an encrypted first key, the computer program product comprising: computer readable program code devices configured to cause a computer to receive at least a portion of the key recovery file; computer readable program code devices configured to cause a computer to receive a second key; computer readable program code devices configured to cause a computer using a first decryptor to decrypt the portion of the key recovery file received responsive to the second key received; computer readable program code devices configured to cause a computer to receive a first set of private information; computer readable program code devices configured to cause a computer to encode the first set of private information received; and computer readable program code devices configured to cause a computer using a second decryptor to, responsive to the first set of private information encoded, decrypt the portion of the key recovery file.
Claim 28
Dependent Claim 62 words
The computer program product of claim 24 wherein the computer readable program code devices configured to cause a computer to receive private information comprise: computer readable program code devices configured to cause a computer to provide an index; and computer readable program code devices configured to cause a computer to receive the first set of private information responsive to the index provided.
Claim 29
Dependent Claim 60 words
The computer program product of claim 25, wherein: the computer readable program code devices configured to cause a computer to receive private information step additionally comprise computer readable program code devices configured to cause a computer to receive an index; the index provided comprises at least a portion of the index received; and the index received comprises a public key.
Claim 30
Dependent Claim 110 words
The computer program product of claim 26 additionally comprising: computer readable program code devices configured to cause a computer to receive a second set of private information; computer readable program code devices configured to cause a computer to compare the first set of private information received with the second set of private information received; and wherein the computer readable program code devices configured to cause a computer to encode the first set of private information and decrypt the key recovery file responsive to the first set of private information encoded are responsive to the first set of private information received being equivalent to the second set of private information received.
Claim 31
Dependent Claim 45 words
The computer program product of claim 24 wherein the computer readable program code devices configured to cause a computer to encode comprise computer readable program code devices configured to cause a computer to hash the first set of private information received using a hash function.
Claim 32
Dependent Claim 18 words
The computer program product of claim 28 wherein the hash function one selected from is SHA-1 and MD-5.
Claim 33
Dependent Claim 53 words
The computer program product of claim 24, wherein the computer readable program code devices configured to cause a computer to decrypt comprise computer readable program code devices configured to cause a computer to DES decrypt the key recovery file decrypted using the encoder first set of private information encoded as a decryption key.
Claim 34
Dependent Claim 51 words
The computer program product of claim 24, wherein computer readable program code devices configured to cause a computer to decrypt the key recovery file comprise computer readable program code devices configured to cause a computer to asymmetrically decrypt the key recovery file using the second key received as a decryption key.
Claim 35
Dependent Claim 15 words
The computer program product of claim 24, wherein the second key is a private key.
Claim 36
Dependent Claim 51 words
The computer program product of claim 32 wherein: the encrypted first key is produced from one selected from a key password of a first private key generated by a certificate authority and a first private key generated by a certificate authority; and the second key comprises a certificate authority private key.
Claim 37
Dependent Claim 19 words
The computer program product of claim 24 wherein the first decryptor and the second decryptor are the same decryptor.

References Cited (Backward Citations)

US5237610A Cited
US5757913A Cited
US5481613A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2003-12-12 2004-06-12 2004-12-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2007-12-12 2008-06-12 2008-12-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2011-12-12 2012-06-12 2012-12-12 $7700.00 Window Closed / Lapsed

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