Supporting DNS security in a multi-master environment

1. A method comprising:

generating a signing key descriptor that identifies how a domain name system (DNS) zone is to be signed;

generating, at a first peer DNS server of a multi-master DNS environment and based at least in part on the signing key descriptor, a set of one or more keys for the DNS zone;

storing the set of one or more keys for the DNS zone in a key store; and

providing the signing key descriptor to a second peer DNS server of the multi-master DNS environment, the signing key descriptor including a pointer to the set of one or more keys in the key store, the key store being remote from the second peer DNS server.

2. A method as recited in claim 1 , wherein the set of one or more keys includes one or more private keys of public/private key pairs used to generate digital signatures for DNS data for the DNS zone.

3. A method as recited in claim 2 , wherein no peer DNS servers in the multi-master DNS environment, other than the first peer DNS server, generate public/private key pairs used to generate digital signatures for DNS data in the DNS zone.

4. A method as recited in claim 2 , further comprising:

generating a key record that includes one or more public keys of the public/private key pairs;

generating a digital signature by digitally signing the key record; and

providing the key record and the digital signature to the second peer DNS server.

5. A method as recited in claim 1 , wherein the signing key descriptor includes one or more parameters used to generate digital signatures for DNS data in the DNS zone.

6. A method as recited in claim 1 , further comprising providing the signing key descriptor from the first peer DNS server to each of one or more additional DNS servers of the multi-master DNS environment.

7. A method as recited in claim 1 , wherein the set of one or more keys comprises one or more keys used to support security extensions for the DNS zone.

8. A method as recited in claim 1 , further comprising:

receiving an update to a mapping of a name to a corresponding network address for the DNS zone;

generating a digital signature by digitally signing DNS data in the update;

storing the updated mapping and the digital signature in a data store of the first peer DNS server; and

cause the update to the mapping to be communicated to the second peer DNS server.

9. A device comprising:

one or more processors; and

memory storing instructions which, responsive to execution by the one or more processors, cause the device to perform operations comprising:

receiving, at a first peer domain name system (DNS) server, a signing key descriptor from a second peer DNS server, the first peer DNS server and the second peer DNS server each being DNS servers for a DNS zone of a multi-master DNS environment;

causing one or more keys to be obtained from a key store remote from the first peer DNS server; and

using the one or more keys to generate, based at least in part on the signing key descriptor, digital signatures for DNS data for the DNS zone.

10. A device as recited in claim 9 , the operations further comprising retrieving, from the signing key descriptor, one or more identifiers of the one or more keys maintained in the key store, and wherein causing the one or more keys to be obtained from the key store is based on the one or more identifiers.

11. A device as recited in claim 9 , the operations further comprising maintaining mappings of names to corresponding network addresses for the DNS zone in a volatile memory.

12. A device as recited in claim 11 the operations further comprising:

generating a digital signature by digitally signing each mapping stored in the volatile memory using at least one of the one or more keys; and

maintaining each digitally signed mapping in the volatile memory store.

13. A device as recited in claim 11 , the operations further comprising:

receiving an update to a mapping of a name to a corresponding network address for the DNS zone;

generating a digital signature by digitally signing DNS data in the update;

storing the updated mapping and the digital signature in the volatile memory; and

causing the update to the mapping to be communicated to the second peer DNS server.

14. A device as recited in claim 9 , wherein the one or more keys includes one or more private keys of one or more public/private key pairs.

15. A device as recited in claim 9 , wherein the first peer DNS server does not use any keys generated by the first peer DNS server to generate digital signatures for DNS data for the DNS zone.

16. A device as recited in claim 9 , the operations further comprising:

retrieving, from the signing key descriptor, one or more parameters; and

using the one or more parameters to generate the digital signatures for the DNS data for the DNS zone.

17. A device as recited in claim 9 , the operations further comprising:

verifying the one or more keys; and

wherein using the one or more keys includes using the one or more keys only if the one or more keys are verified.

18. A device as recited in claim 9 , wherein the one or more keys comprises one or more keys used to support security extensions for the DNS zone.

19. A device comprising:

one or more processors; and

memory storing instructions which, responsive to execution by the one or more processors, cause the device to perform operations comprising:

generating, at a first peer domain name system (DNS) DNS server, a signing key descriptor that identifies how the DNS zone is to be signed;

generating, at the first peer DNS server, a set of one or more keys for the DNS zone, the first peer DNS server being a key master peer DNS server of a multi-master DNS environment; and

providing the signing key descriptor to a second peer DNS server of the multi-master DNS environment, the signing key descriptor including a pointer to a set of public/private key pairs in a key store remote from the second peer DNS server, the set of public/private key pairs including one or more private keys used by both the first peer DNS server and the second peer DNS server to generate digital signatures for DNS data in the DNS zone.

20. A device as recited in claim 9 , the first peer DNS server and the second peer DNS server each being enabled to produce different digital signatures.