Author: abartlet Date: 2006-07-23 02:50:08 +0000 (Sun, 23 Jul 2006) New Revision: 17197
WebSVN: http://websvn.samba.org/cgi-bin/viewcvs.cgi?view=rev&root=samba&rev=17197 Log: This patch moves the encryption of bulk data on SASL negotiated security contexts from the application layer into the socket layer. This improves a number of correctness aspects, as we now allow LDAP packets to cross multiple SASL packets. It should also make it much easier to write async LDAP tests from windows clients, as they use SASL by default. It is also vital to allowing OpenLDAP clients to use GSSAPI against Samba4, as it negotiates a rather small SASL buffer size. This patch mirrors the earlier work done to move TLS into the socket layer. Unusual in this pstch is the extra read callback argument I take. As SASL is a layer on top of a socket, it is entirely possible for the SASL layer to drain a socket dry, but for the caller not to have read all the decrypted data. This would leave the system without an event to restart the read (as the socket is dry). As such, I re-invoke the read handler from a timed callback, which should trigger on the next running of the event loop. I believe that the TLS code does require a similar callback. In trying to understand why this is required, imagine a SASL-encrypted LDAP packet in the following formation: +-----------------+---------------------+ | SASL Packet #1 | SASL Packet #2 | ----------------------------------------+ | LDAP Packet #1 | LDAP Packet #2 | ----------------------------------------+ In the old code, this was illegal, but it is perfectly standard SASL-encrypted LDAP. Without the callback, we would read and process the first LDAP packet, and the SASL code would have read the second SASL packet (to decrypt enough data for the LDAP packet), and no data would remain on the socket. Without data on the socket, read events stop. That is why I add timed events, until the SASL buffer is drained. Another approach would be to add a hack to the event system, to have it pretend there remained data to read off the network (but that is ugly). In improving the code, to handle more real-world cases, I've been able to remove almost all the special-cases in the testnonblock code. The only special case is that we must use a deterministic partial packet when calling send, rather than a random length. (1 + n/2). This is needed because of the way the SASL and TLS code works, and the 'resend on failure' requirements. Andrew Bartlett Added: branches/SAMBA_4_0/source/auth/gensec/socket.c branches/SAMBA_4_0/source/auth/gensec/socket.h Modified: branches/SAMBA_4_0/source/auth/gensec/config.mk branches/SAMBA_4_0/source/auth/gensec/spnego.c branches/SAMBA_4_0/source/ldap_server/config.mk branches/SAMBA_4_0/source/ldap_server/ldap_bind.c branches/SAMBA_4_0/source/ldap_server/ldap_server.c branches/SAMBA_4_0/source/ldap_server/ldap_server.h branches/SAMBA_4_0/source/lib/socket/socket.c branches/SAMBA_4_0/source/lib/socket/socket.h branches/SAMBA_4_0/source/lib/stream/packet.c branches/SAMBA_4_0/source/lib/stream/packet.h branches/SAMBA_4_0/source/lib/tls/tls.c branches/SAMBA_4_0/source/libcli/ldap/config.mk branches/SAMBA_4_0/source/libcli/ldap/ldap_bind.c branches/SAMBA_4_0/source/libcli/ldap/ldap_client.c branches/SAMBA_4_0/source/libcli/ldap/ldap_client.h branches/SAMBA_4_0/source/smbd/service_stream.c Changeset: Sorry, the patch is too large (1340 lines) to include; please use WebSVN to see it! WebSVN: http://websvn.samba.org/cgi-bin/viewcvs.cgi?view=rev&root=samba&rev=17197
