From b3e3d4cacca37a4850e4e1a91fb8c42a5b13cb26 Mon Sep 17 00:00:00 2001 From: Adam Ierymenko Date: Mon, 11 Jan 2016 10:17:44 -0800 Subject: Instead of using binary packet comparison, add a callback to the API to explicitly check whether paths should be used. Check in with this callback (if present) when learning new paths or sending initial packets. --- include/ZeroTierOne.h | 45 ++++++++++++++++++++++++++++++++++++++------- 1 file changed, 38 insertions(+), 7 deletions(-) (limited to 'include') diff --git a/include/ZeroTierOne.h b/include/ZeroTierOne.h index 39959221..e087904f 100644 --- a/include/ZeroTierOne.h +++ b/include/ZeroTierOne.h @@ -1097,13 +1097,42 @@ typedef int (*ZT_DataStorePutFunction)( * delivery. It only means that the packet appears to have been sent. */ typedef int (*ZT_WirePacketSendFunction)( - ZT_Node *, /* Node */ - void *, /* User ptr */ - const struct sockaddr_storage *, /* Local address */ - const struct sockaddr_storage *, /* Remote address */ - const void *, /* Packet data */ - unsigned int, /* Packet length */ - unsigned int); /* TTL or 0 to use default */ + ZT_Node *, /* Node */ + void *, /* User ptr */ + const struct sockaddr_storage *, /* Local address */ + const struct sockaddr_storage *, /* Remote address */ + const void *, /* Packet data */ + unsigned int, /* Packet length */ + unsigned int); /* TTL or 0 to use default */ + +/** + * Function to check whether a path should be used for ZeroTier traffic + * + * Paramters: + * (1) Node + * (2) User pointer + * (3) Local interface address + * (4) Remote address + * + * This function must return nonzero (true) if the path should be used. + * + * If no path check function is specified, ZeroTier will still exclude paths + * that overlap with ZeroTier-assigned and managed IP address blocks. But the + * use of a path check function is recommended to ensure that recursion does + * not occur in cases where addresses are assigned by the OS or managed by + * an out of band mechanism like DHCP. The path check function should examine + * all configured ZeroTier interfaces and check to ensure that the supplied + * addresses will not result in ZeroTier traffic being sent over a ZeroTier + * interface (recursion). + * + * Obviously this is not required in configurations where this can't happen, + * such as network containers or embedded. + */ +typedef int (*ZT_PathCheckFunction)( + ZT_Node *, /* Node */ + void *, /* User ptr */ + const struct sockaddr_storage *, /* Local address */ + const struct sockaddr_storage *); /* Remote address */ /****************************************************************************/ /* C Node API */ @@ -1121,6 +1150,7 @@ typedef int (*ZT_WirePacketSendFunction)( * @param dataStoreGetFunction Function called to get objects from persistent storage * @param dataStorePutFunction Function called to put objects in persistent storage * @param virtualNetworkConfigFunction Function to be called when virtual LANs are created, deleted, or their config parameters change + * @param pathCheckFunction A function to check whether a path should be used for ZeroTier traffic, or NULL to allow any path * @param eventCallback Function to receive status updates and non-fatal error notices * @return OK (0) or error code if a fatal error condition has occurred */ @@ -1133,6 +1163,7 @@ enum ZT_ResultCode ZT_Node_new( ZT_WirePacketSendFunction wirePacketSendFunction, ZT_VirtualNetworkFrameFunction virtualNetworkFrameFunction, ZT_VirtualNetworkConfigFunction virtualNetworkConfigFunction, + ZT_PathCheckFunction pathCheckFunction, ZT_EventCallback eventCallback); /** -- cgit v1.2.3