handshake_complete() declares status as unsigned int and
tls_handshake_done() negates that value (-status) before handing
it to the TLS consumer. Consumers match on negative errno
constants -- xs_tls_handshake_done() has
switch (status) {
case 0:
case -EACCES:
case -ETIMEDOUT:
lower_transport->xprt_err = status;
break;
default:
lower_transport->xprt_err = -EACCES;
}
so the API as designed expects callers to pass positive errno
values that the tlshd shim then negates.
Three internal callers in handshake_nl_accept_doit(), the
net-exit drain, and a kunit test follow kernel convention and
pass negative errnos -- -EIO, -ETIMEDOUT, -ETIMEDOUT. The
implicit conversion to unsigned int turns -ETIMEDOUT into
0xFFFFFF92; the subsequent -status in tls_handshake_done()
wraps back to 110, the consumer's switch falls through, and
the xprt reports -EACCES on what should be -ETIMEDOUT or -EIO.
Fix the API rather than the call sites. The natural kernel
convention is negative errno in, negative errno out. Change
handshake_complete() and hp_done to take int status, drop the
negation in tls_handshake_done(), and negate once in
handshake_nl_done_doit() where status arrives from the wire
as an unsigned netlink attribute. The three internal callers
were already correct under that convention and need no change.
At the same wire boundary, declare MAX_ERRNO as the netlink
policy upper bound for HANDSHAKE_A_DONE_STATUS. Attribute
validation rejects out-of-range values before
handshake_nl_done_doit() runs, and negating a bounded u32 there
stays within int range -- closing the UBSAN-visible signed-
integer overflow that an unconstrained u32 would invoke.
Fixes: 3b3009ea8a ("net/handshake: Create a NETLINK service for handling handshake requests")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Link: https://patch.msgid.link/20260525-handshake-file-pin-v3-3-66c616906ead@oracle.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add a new netlink parameter 'HANDSHAKE_A_ACCEPT_KEYRING' to provide
the serial number of the keyring to use.
Signed-off-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Link: https://patch.msgid.link/20250701144657.104401-1-hare@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Clean up all space inside brackets errors reported by yamllint in
the netlink specs:
error too many spaces inside brackets (brackets)
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> # mptcp_pm.yaml
Link: https://patch.msgid.link/20250610125944.85265-3-donald.hunter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Clean up all document-start warnings reported by yamllint in the
netlink specs:
warning missing document start "---" (document-start)
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> # mptcp_pm.yaml
Link: https://patch.msgid.link/20250610125944.85265-2-donald.hunter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
key_serial_t fields are signed integers. Use nla_get/put_s32 for
those to avoid implicit signed conversion in the netlink protocol.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/169530167716.8905.645746457741372879.stgit@oracle-102.nfsv4bat.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Socket file descriptors are signed integers. Use nla_get/put_s32 for
those to avoid implicit signed conversion in the netlink protocol.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/169530165057.8905.8650469415145814828.stgit@oracle-102.nfsv4bat.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Enable the upper layer protocol to specify the SNI peername. This
avoids the need for tlshd to use a DNS lookup, which can return a
hostname that doesn't match the incoming certificate's SubjectName.
Fixes: 2fd5532044 ("net/handshake: Add a kernel API for requesting a TLSv1.3 handshake")
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
To enable kernel consumers of TLS to request a TLS handshake, add
support to net/handshake/ to request a handshake upcall.
This patch also acts as a template for adding handshake upcall
support for other kernel transport layer security providers.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When a kernel consumer needs a transport layer security session, it
first needs a handshake to negotiate and establish a session. This
negotiation can be done in user space via one of the several
existing library implementations, or it can be done in the kernel.
No in-kernel handshake implementations yet exist. In their absence,
we add a netlink service that can:
a. Notify a user space daemon that a handshake is needed.
b. Once notified, the daemon calls the kernel back via this
netlink service to get the handshake parameters, including an
open socket on which to establish the session.
c. Once the handshake is complete, the daemon reports the
session status and other information via a second netlink
operation. This operation marks that it is safe for the
kernel to use the open socket and the security session
established there.
The notification service uses a multicast group. Each handshake
mechanism (eg, tlshd) adopts its own group number so that the
handshake services are completely independent of one another. The
kernel can then tell via netlink_has_listeners() whether a handshake
service is active and prepared to handle a handshake request.
A new netlink operation, ACCEPT, acts like accept(2) in that it
instantiates a file descriptor in the user space daemon's fd table.
If this operation is successful, the reply carries the fd number,
which can be treated as an open and ready file descriptor.
While user space is performing the handshake, the kernel keeps its
muddy paws off the open socket. A second new netlink operation,
DONE, indicates that the user space daemon is finished with the
socket and it is safe for the kernel to use again. The operation
also indicates whether a session was established successfully.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Chuck Lever