diff options
author | Chuck Lever <chuck.lever@oracle.com> | 2023-04-20 20:56:24 +0300 |
---|---|---|
committer | Chuck Lever <chuck.lever@oracle.com> | 2023-04-28 01:49:24 +0300 |
commit | b3cbf98e2fdf3cb147a95161560cd25987284330 (patch) | |
tree | cf08005abc4b034ba5a9b0a1c229dcb83b128325 /net/sunrpc | |
parent | 22b620ec0bf454cfd1c464f57cfce9afb3fb1e70 (diff) | |
download | linux-b3cbf98e2fdf3cb147a95161560cd25987284330.tar.xz |
SUNRPC: Support TLS handshake in the server-side TCP socket code
This patch adds opportunitistic RPC-with-TLS to the Linux in-kernel
NFS server. If the client requests RPC-with-TLS and the user space
handshake agent is running, the server will set up a TLS session.
There are no policy settings yet. For example, the server cannot
yet require the use of RPC-with-TLS to access its data.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Diffstat (limited to 'net/sunrpc')
-rw-r--r-- | net/sunrpc/svc_xprt.c | 5 | ||||
-rw-r--r-- | net/sunrpc/svcauth_unix.c | 11 | ||||
-rw-r--r-- | net/sunrpc/svcsock.c | 101 |
3 files changed, 111 insertions, 6 deletions
diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c index 3b9708b39e35..84e5d7d31481 100644 --- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -427,7 +427,7 @@ static bool svc_xprt_ready(struct svc_xprt *xprt) if (xpt_flags & BIT(XPT_BUSY)) return false; - if (xpt_flags & (BIT(XPT_CONN) | BIT(XPT_CLOSE))) + if (xpt_flags & (BIT(XPT_CONN) | BIT(XPT_CLOSE) | BIT(XPT_HANDSHAKE))) return true; if (xpt_flags & (BIT(XPT_DATA) | BIT(XPT_DEFERRED))) { if (xprt->xpt_ops->xpo_has_wspace(xprt) && @@ -828,6 +828,9 @@ static int svc_handle_xprt(struct svc_rqst *rqstp, struct svc_xprt *xprt) module_put(xprt->xpt_class->xcl_owner); } svc_xprt_received(xprt); + } else if (test_bit(XPT_HANDSHAKE, &xprt->xpt_flags)) { + xprt->xpt_ops->xpo_handshake(xprt); + svc_xprt_received(xprt); } else if (svc_xprt_reserve_slot(rqstp, xprt)) { /* XPT_DATA|XPT_DEFERRED case: */ dprintk("svc: server %p, pool %u, transport %p, inuse=%d\n", diff --git a/net/sunrpc/svcauth_unix.c b/net/sunrpc/svcauth_unix.c index 4485088ce27b..174783f804fa 100644 --- a/net/sunrpc/svcauth_unix.c +++ b/net/sunrpc/svcauth_unix.c @@ -17,8 +17,9 @@ #include <net/ipv6.h> #include <linux/kernel.h> #include <linux/user_namespace.h> -#define RPCDBG_FACILITY RPCDBG_AUTH +#include <trace/events/sunrpc.h> +#define RPCDBG_FACILITY RPCDBG_AUTH #include "netns.h" @@ -832,6 +833,7 @@ svcauth_tls_accept(struct svc_rqst *rqstp) { struct xdr_stream *xdr = &rqstp->rq_arg_stream; struct svc_cred *cred = &rqstp->rq_cred; + struct svc_xprt *xprt = rqstp->rq_xprt; u32 flavor, len; void *body; __be32 *p; @@ -865,14 +867,19 @@ svcauth_tls_accept(struct svc_rqst *rqstp) if (cred->cr_group_info == NULL) return SVC_CLOSE; - if (rqstp->rq_xprt->xpt_ops->xpo_start_tls) { + if (xprt->xpt_ops->xpo_handshake) { p = xdr_reserve_space(&rqstp->rq_res_stream, XDR_UNIT * 2 + 8); if (!p) return SVC_CLOSE; + trace_svc_tls_start(xprt); *p++ = rpc_auth_null; *p++ = cpu_to_be32(8); memcpy(p, "STARTTLS", 8); + + set_bit(XPT_HANDSHAKE, &xprt->xpt_flags); + svc_xprt_enqueue(xprt); } else { + trace_svc_tls_unavailable(xprt); if (xdr_stream_encode_opaque_auth(&rqstp->rq_res_stream, RPC_AUTH_NULL, NULL, 0) < 0) return SVC_CLOSE; diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index c5b74f523fc4..a51c9b989d58 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -44,9 +44,11 @@ #include <net/tcp.h> #include <net/tcp_states.h> #include <net/tls.h> +#include <net/handshake.h> #include <linux/uaccess.h> #include <linux/highmem.h> #include <asm/ioctls.h> +#include <linux/key.h> #include <linux/sunrpc/types.h> #include <linux/sunrpc/clnt.h> @@ -64,6 +66,12 @@ #define RPCDBG_FACILITY RPCDBG_SVCXPRT +/* To-do: to avoid tying up an nfsd thread while waiting for a + * handshake request, the request could instead be deferred. + */ +enum { + SVC_HANDSHAKE_TO = 5U * HZ +}; static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *, int flags); @@ -359,6 +367,8 @@ static void svc_data_ready(struct sock *sk) rmb(); svsk->sk_odata(sk); trace_svcsock_data_ready(&svsk->sk_xprt, 0); + if (test_bit(XPT_HANDSHAKE, &svsk->sk_xprt.xpt_flags)) + return; if (!test_and_set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags)) svc_xprt_enqueue(&svsk->sk_xprt); } @@ -396,6 +406,88 @@ static void svc_tcp_kill_temp_xprt(struct svc_xprt *xprt) sock_no_linger(svsk->sk_sock->sk); } +/** + * svc_tcp_handshake_done - Handshake completion handler + * @data: address of xprt to wake + * @status: status of handshake + * @peerid: serial number of key containing the remote peer's identity + * + * If a security policy is specified as an export option, we don't + * have a specific export here to check. So we set a "TLS session + * is present" flag on the xprt and let an upper layer enforce local + * security policy. + */ +static void svc_tcp_handshake_done(void *data, int status, key_serial_t peerid) +{ + struct svc_xprt *xprt = data; + struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); + + if (!status) { + if (peerid != TLS_NO_PEERID) + set_bit(XPT_PEER_AUTH, &xprt->xpt_flags); + set_bit(XPT_TLS_SESSION, &xprt->xpt_flags); + } + clear_bit(XPT_HANDSHAKE, &xprt->xpt_flags); + complete_all(&svsk->sk_handshake_done); +} + +/** + * svc_tcp_handshake - Perform a transport-layer security handshake + * @xprt: connected transport endpoint + * + */ +static void svc_tcp_handshake(struct svc_xprt *xprt) +{ + struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); + struct sock *sk = svsk->sk_sock->sk; + struct tls_handshake_args args = { + .ta_sock = svsk->sk_sock, + .ta_done = svc_tcp_handshake_done, + .ta_data = xprt, + }; + int ret; + + trace_svc_tls_upcall(xprt); + + clear_bit(XPT_TLS_SESSION, &xprt->xpt_flags); + init_completion(&svsk->sk_handshake_done); + + ret = tls_server_hello_x509(&args, GFP_KERNEL); + if (ret) { + trace_svc_tls_not_started(xprt); + goto out_failed; + } + + ret = wait_for_completion_interruptible_timeout(&svsk->sk_handshake_done, + SVC_HANDSHAKE_TO); + if (ret <= 0) { + if (tls_handshake_cancel(sk)) { + trace_svc_tls_timed_out(xprt); + goto out_close; + } + } + + if (!test_bit(XPT_TLS_SESSION, &xprt->xpt_flags)) { + trace_svc_tls_unavailable(xprt); + goto out_close; + } + + /* Mark the transport ready in case the remote sent RPC + * traffic before the kernel received the handshake + * completion downcall. + */ + set_bit(XPT_DATA, &xprt->xpt_flags); + svc_xprt_enqueue(xprt); + return; + +out_close: + set_bit(XPT_CLOSE, &xprt->xpt_flags); +out_failed: + clear_bit(XPT_HANDSHAKE, &xprt->xpt_flags); + set_bit(XPT_DATA, &xprt->xpt_flags); + svc_xprt_enqueue(xprt); +} + /* * See net/ipv6/ip_sockglue.c : ip_cmsg_recv_pktinfo */ @@ -1257,6 +1349,7 @@ static const struct svc_xprt_ops svc_tcp_ops = { .xpo_has_wspace = svc_tcp_has_wspace, .xpo_accept = svc_tcp_accept, .xpo_kill_temp_xprt = svc_tcp_kill_temp_xprt, + .xpo_handshake = svc_tcp_handshake, }; static struct svc_xprt_class svc_tcp_class = { @@ -1580,10 +1673,12 @@ static void svc_tcp_sock_detach(struct svc_xprt *xprt) static void svc_sock_free(struct svc_xprt *xprt) { struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); + struct socket *sock = svsk->sk_sock; - if (svsk->sk_sock->file) - sockfd_put(svsk->sk_sock); + tls_handshake_cancel(sock->sk); + if (sock->file) + sockfd_put(sock); else - sock_release(svsk->sk_sock); + sock_release(sock); kfree(svsk); } |