Secure patch system

A method of providing a patch to a patch client, comprising:

• generating a first private key group comprising a plurality of first private keys using a first key generation platform;
• generating a second private key group comprising a plurality of second private keys using a second key generation platform different from said first key generation platform;
• selecting one of said first private keys from said first private key group;
• selecting one of said second private keys from said second private key group;
• generating a first digital signature based on said patch and said first selected private key;
• generating a second digital signature based on said patch and said second selected private key;
• and
• transmitting said patch together with said first and second digital signatures to said patch client.

A patch client connected to a patch server for receiving a patch from said patch server, the patch client comprising:

• first storage means storing a first public key group comprising a plurality of first public keys which have been generated by a first key generation platform;
• second storage means storing a second public key group comprising a plurality of second public keys which have been generated by a second key generation platform different from said first key generation platform;
• a first key selector arranged to select one of said first public keys from said first public key group;
• a second key selector arranged to select one of said second public keys from said second public key group;
• a first signature verification component arranged to verify a first digital signature received from said patch server together with said patch using said first selected public key;
• and
• a second signature verification component arranged to verify a second digital signature received from said patch server together with said patch using said second selected public key;
• wherein said patch client is arranged to install said patch only if the results of verifying said first and second digital signatures indicate authenticity and integrity of said first and second digital signatures, respectively.

A method of installing a patch in a patch client, comprising:

• receiving said patch together with a first digital signature and a second digital signature from a patch server connected to said patch client;
• storing a first public key group comprising a plurality of first public keys in said patch client, wherein said first public keys have been generated by a first key generation platform;
• storing a second public key group comprising a plurality of second public keys in said patch client, wherein said second public keys have been generated by a second key generation platform different from said first key generation platform;
• selecting one of said first public keys from said first public key group;
• selecting one of said second public keys from said second public key group;
• verifying said first digital signature using said first selected public key;
• verifying said second digital signature using said second selected public key;
• and
• installing said patch in said patch client only if the results of verifying said first and second digital signatures indicate authenticity and integrity of said first and second digital signatures, respectively.