Selectively performing man in the middle decryption

1. A method performed by data processing apparatus, the method comprising:

receiving, by a gateway on a network, from a client device within the network, a Hypertext Transfer Protocol (HTTP) request addressed to a first resource on a server outside the network;

determining, by the gateway, a class of network traffic of which the received HTTP request is a member, the determining being based on a comparison of the first resource with a rule defining destinations associated with encrypted communication traffic for each class;

selecting, by the gateway, a man-in-the-middle gateway within the network from a plurality of available man-in-the-middle gateways within the network, wherein each available man-in-the-middle gateway is associated with a class of network traffic and wherein the selected man in the selected middle gateway is selected based on having a class that is the same as the determined class of the HTTP request;

sending, from the gateway to the client device, a message redirecting the HTTP request to the selected man-in-the-middle-gateway within the network;

establishing a first encrypted connection between the client device and the selected man-in-the-middle-gateway, and a second encrypted connection between the selected man-in-the-middle-gateway and the server;

retrieving, by the selected man-in-the-middle-gateway, the first resource from the server;

modifying the first resource to change pointers within the first resource to point to location in a domain associated with the selected man-in-the-middle-gateway within the network; and

serving, by the selected man-in-the-middle-gateway to the client device, the modified first resource.

2. The method of claim 1 , wherein the selected man-in-the-middle-gateway is selected based on a comparison of the first resource with a rule defining destinations associated with encrypted communication traffic.

3. The method of claim 1 , wherein the selected man-in-the-middle-gateway is selected based on hardware performance.

4. The method of claim 1 , the method further comprising:

receiving, from a fourth device within the network, a second HTTP request addressed to an address of a second resource on a fifth device outside the network; and

routing the HTTP request to the address of the second resource.

5. The method of claim 1 , the method further comprising modifying the first resource to conform with the security policy.

6. The method of claim 1 , the method further comprising modifying the first resource comprises replacing the resource with a different resource.

7. The method of claim 1 , the method further comprising modifying the first resource comprises replacing HTTP links in the resource with different HTTP links.

8. The method of claim 1 , the method further comprising modifying the first resource comprises replacing the resource with an HTTP status code object.

9. The method of claim 1 , the method further comprising determining that a security policy of the network identifies the first resource for inspection upon entry to the network.

10. The method of claim 1 , wherein the determined class of network traffic of which the received HTTP request is a member of HTTP or Hypertext Transfer Protocol Secure (HTTPS) protocol.

11. A non-transitory computer storage media encoded with computer program instructions that, when executed by one or more processors, cause a computer device to perform operations comprising:

receiving, by a gateway on a network, from a client device within the network, a HTTP request addressed to a first resource on a server outside the network;

determining, by the gateway, a class of network traffic of which the received HTTP request is a member, the determining being based on a comparison of the first resource with a rule defining destinations associated with encrypted communication traffic for each class;

selecting, by the gateway, a man-in-the-middle gateway within the network from a plurality of available man-in-the-middle gateways within the network, wherein each available man-in-the-middle gateway is associated with a class of network traffic and wherein the selected man in the selected middle gateway is selected based on having a class that is the same as the determined class of the HTTP request;

sending, from the gateway to the client device, a message redirecting the HTTP request to the selected man-in-the-middle-gateway within the network;

establishing a first encrypted connection between the client device and the selected man-in-the-middle-gateway, and a second encrypted connection between the selected man-in-the-middle-gateway and the server;

retrieving, by the selected man-in-the-middle-gateway, the first resource from the server;

modifying the first resource to change pointers within the first resource to point to location in a domain associated with the selected man-in-the-middle-gateway within the network; and

serving, by the selected man-in-the-middle-gateway to the client device, the modified first resource.

12. The computer storage media of claim 11 , wherein the selected man-in-the-middle-gateway is selected based on a comparison of the first resource with a rule defining destinations associated with encrypted communication traffic.

13. The computer storage media of claim 11 , wherein the selected man-in-the-middle-gateway is selected based on hardware performance.

14. The computer storage media of claim 11 , the instructions further comprising:

receiving, from a fourth device within the network, a second HTTP request addressed to an address of a second resource on a fifth device outside the network; and

routing the HTTP request to the address of the second resource.

15. The computer storage media of claim 11 , the instructions further comprising modifying the first resource to conform with the security policy.

16. The computer storage media of claim 11 , the instructions further comprising modifying the first resource comprises replacing the resource with a different resource.

17. The computer storage media of claim 11 , the instructions further comprising modifying the first resource comprises replacing HTTP links in the resource with different HTTP links.

18. The computer storage media of claim 11 , the instructions further comprising modifying the first resource comprises replacing the resource with an HTTP status code object.

19. The computer storage media of claim 11 , the instructions further comprising determining that a security policy of the network identifies the first resource for inspection upon entry to the network.

20. The computer storage media of claim 11 , wherein the determined class of network traffic of which the received HTTP request is a member of HTTP or HTTPS protocol.

21. A system comprising:

one or more processors configured to execute computer program instructions; and

computer storage media encoded with computer program instructions that, when executed by one or more processors, cause a computer device to perform operations comprising:

receiving, by a gateway on a network, from a client device within the network, a Hypertext Transfer Protocol (HTTP) request addressed to a first resource on a server outside the network;

determining, by the gateway, a class of network traffic of which the received HTTP request is a member, the determining being based on a comparison of the first resource with a rule defining destinations associated with encrypted communication traffic for each class;

selecting, by the gateway, a man-in-the-middle gateway within the network from a plurality of available man-in-the-middle gateways within the network, wherein each available man-in-the-middle gateway is associated with a class of network traffic and wherein the selected man in the selected middle gateway is selected based on having a class that is the same as the determined class of the HTTP request;

sending, from the gateway to the client device, a message redirecting the HTTP request to the selected man-in-the-middle-gateway within the network;

establishing a first encrypted connection between the client device and the selected man-in-the-middle-gateway, and a second encrypted connection between the selected man-in-the-middle-gateway and the server;

retrieving, by the selected man-in-the-middle-gateway, the first resource from the server;

modifying the first resource to change pointers within the first resource to point to location in a domain associated with the selected man-in-the-middle-gateway within the network; and

serving, by the selected man-in-the-middle-gateway to the client device, the modified first resource.

22. The system of claim 21 , wherein the selected man-in-the-middle-gateway is selected based on a comparison of the first resource with a rule defining destinations associated with encrypted communication traffic.

23. The system of claim 21 , wherein the selected man-in-the-middle-gateway is selected based on hardware performance.

24. The system of claim 21 , the operations further comprising:

receiving, from a fourth device within the network, a second HTTP request addressed to an address of a second resource on a fifth device outside the network; and

routing the HTTP request to the address of the second resource.

25. The system of claim 21 , the operations further comprising modifying the first resource to conform with the security policy.

26. The system of claim 21 , the operations further comprising modifying the first resource comprises replacing the resource with a different resource.

27. The system of claim 21 , the operations further comprising modifying the first resource comprises replacing HTTP links in the resource with different HTTP links.

28. The system of claim 21 , the operations further comprising modifying the first resource comprises replacing the resource with an HTTP status code object.

29. The system of claim 21 , the operations further comprising determining that a security policy of the network identifies the first resource for inspection upon entry to the network.

30. The system of claim 21 , wherein the determined class of network traffic of which the received HTTP request is a member of HTTP or HTTPS protocol.