From: Chuck Lever <chuck.lever@xxxxxxxxxx>
After some discussion, we decided that controlling transport layer
security policy should be separate from the setting for the user
authentication flavor. To accomplish this, add a new NFS mount
option to select a transport layer security policy for RPC
operations associated with the mount point.
xprtsec=none - Transport layer security is forced off.
xprtsec=tls - Establish an encryption-only TLS session. If
the initial handshake fails, the mount fails.
If TLS is not available on a reconnect, drop
the connection and try again.
xprtsec=mtls - Both sides authenticate and an encrypted
session is created. If the initial handshake
fails, the mount fails. If TLS is not available
on a reconnect, drop the connection and try
again.
To support client peer authentication (mtls), the handshake daemon
will have configurable default authentication material (certificate
or pre-shared key). In the future, mount options can be added that
can provide this material on a per-mount basis.
Updates to mount.nfs (to support xprtsec=auto) and nfs(5) will be
sent under separate cover.
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
fs/nfs/client.c | 6 ++---
fs/nfs/fs_context.c | 62 +++++++++++++++++++++++++++++++++++++++++++++++++++
fs/nfs/internal.h | 1 +
fs/nfs/nfs3client.c | 8 +++++--
fs/nfs/nfs4client.c | 28 +++++++++++++++--------
fs/nfs/super.c | 12 ++++++++++
6 files changed, 102 insertions(+), 15 deletions(-)
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 9bfdade0f6e6..d5441e60d7e1 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -463,6 +463,7 @@ void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
switch (proto) {
case XPRT_TRANSPORT_TCP:
+ case XPRT_TRANSPORT_TCP_TLS:
case XPRT_TRANSPORT_RDMA:
if (retrans == NFS_UNSPEC_RETRANS)
to->to_retries = NFS_DEF_TCP_RETRANS;
@@ -515,6 +516,7 @@ int nfs_create_rpc_client(struct nfs_client *clp,
.version = clp->rpc_ops->version,
.authflavor = flavor,
.cred = cl_init->cred,
+ .xprtsec = cl_init->xprtsec,
};
if (test_bit(NFS_CS_DISCRTRY, &clp->cl_flags))
@@ -680,9 +682,7 @@ static int nfs_init_server(struct nfs_server *server,
.cred = server->cred,
.nconnect = ctx->nfs_server.nconnect,
.init_flags = (1UL << NFS_CS_REUSEPORT),
- .xprtsec = {
- .policy = RPC_XPRTSEC_NONE,
- },
+ .xprtsec = ctx->xprtsec,
};
struct nfs_client *clp;
int error;
diff --git a/fs/nfs/fs_context.c b/fs/nfs/fs_context.c
index 5626d358ee2e..853e8d609bb3 100644
--- a/fs/nfs/fs_context.c
+++ b/fs/nfs/fs_context.c
@@ -18,6 +18,9 @@
#include <linux/nfs_fs.h>
#include <linux/nfs_mount.h>
#include <linux/nfs4_mount.h>
+
+#include <net/handshake.h>
+
#include "nfs.h"
#include "internal.h"
@@ -88,6 +91,7 @@ enum nfs_param {
Opt_vers,
Opt_wsize,
Opt_write,
+ Opt_xprtsec,
};
enum {
@@ -194,6 +198,7 @@ static const struct fs_parameter_spec nfs_fs_parameters[] = {
fsparam_string("vers", Opt_vers),
fsparam_enum ("write", Opt_write, nfs_param_enums_write),
fsparam_u32 ("wsize", Opt_wsize),
+ fsparam_string("xprtsec", Opt_xprtsec),
{}
};
@@ -267,6 +272,20 @@ static const struct constant_table nfs_secflavor_tokens[] = {
{}
};
+enum {
+ Opt_xprtsec_none,
+ Opt_xprtsec_tls,
+ Opt_xprtsec_mtls,
+ nr__Opt_xprtsec
+};
+
+static const struct constant_table nfs_xprtsec_policies[] = {
+ { "none", Opt_xprtsec_none },
+ { "tls", Opt_xprtsec_tls },
+ { "mtls", Opt_xprtsec_mtls },
+ {}
+};
+
/*
* Sanity-check a server address provided by the mount command.
*
@@ -320,9 +339,21 @@ static int nfs_validate_transport_protocol(struct fs_context *fc,
default:
ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
}
+
+ if (ctx->xprtsec.policy != RPC_XPRTSEC_NONE)
+ switch (ctx->nfs_server.protocol) {
+ case XPRT_TRANSPORT_TCP:
+ ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP_TLS;
+ break;
+ default:
+ goto out_invalid_xprtsec_policy;
+ }
+
return 0;
out_invalid_transport_udp:
return nfs_invalf(fc, "NFS: Unsupported transport protocol udp");
+out_invalid_xprtsec_policy:
+ return nfs_invalf(fc, "NFS: Transport does not support xprtsec");
}
/*
@@ -430,6 +461,29 @@ static int nfs_parse_security_flavors(struct fs_context *fc,
return 0;
}
+static int nfs_parse_xprtsec_policy(struct fs_context *fc,
+ struct fs_parameter *param)
+{
+ struct nfs_fs_context *ctx = nfs_fc2context(fc);
+
+ trace_nfs_mount_assign(param->key, param->string);
+
+ switch (lookup_constant(nfs_xprtsec_policies, param->string, -1)) {
+ case Opt_xprtsec_none:
+ ctx->xprtsec.policy = RPC_XPRTSEC_NONE;
+ break;
+ case Opt_xprtsec_tls:
+ ctx->xprtsec.policy = RPC_XPRTSEC_TLS_ANON;
+ break;
+ case Opt_xprtsec_mtls:
+ ctx->xprtsec.policy = RPC_XPRTSEC_TLS_X509;
+ break;
+ default:
+ return nfs_invalf(fc, "NFS: Unrecognized transport security policy");
+ }
+ return 0;
+}
+
static int nfs_parse_version_string(struct fs_context *fc,
const char *string)
{
@@ -696,6 +750,11 @@ static int nfs_fs_context_parse_param(struct fs_context *fc,
if (ret < 0)
return ret;
break;
+ case Opt_xprtsec:
+ ret = nfs_parse_xprtsec_policy(fc, param);
+ if (ret < 0)
+ return ret;
+ break;
case Opt_proto:
if (!param->string)
@@ -1574,6 +1633,9 @@ static int nfs_init_fs_context(struct fs_context *fc)
ctx->selected_flavor = RPC_AUTH_MAXFLAVOR;
ctx->minorversion = 0;
ctx->need_mount = true;
+ ctx->xprtsec.policy = RPC_XPRTSEC_NONE;
+ ctx->xprtsec.cert_serial = TLS_NO_CERT;
+ ctx->xprtsec.privkey_serial = TLS_NO_PRIVKEY;
fc->s_iflags |= SB_I_STABLE_WRITES;
}
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 5c986c0d3cce..0019c7578f9d 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -102,6 +102,7 @@ struct nfs_fs_context {
unsigned int bsize;
struct nfs_auth_info auth_info;
rpc_authflavor_t selected_flavor;
+ struct xprtsec_parms xprtsec;
char *client_address;
unsigned int version;
unsigned int minorversion;
diff --git a/fs/nfs/nfs3client.c b/fs/nfs/nfs3client.c
index 8fa187a9c46d..0844f1651e0f 100644
--- a/fs/nfs/nfs3client.c
+++ b/fs/nfs/nfs3client.c
@@ -103,8 +103,12 @@ struct nfs_client *nfs3_set_ds_client(struct nfs_server *mds_srv,
return ERR_PTR(-EINVAL);
cl_init.hostname = buf;
- if (mds_clp->cl_nconnect > 1 && ds_proto == XPRT_TRANSPORT_TCP)
- cl_init.nconnect = mds_clp->cl_nconnect;
+ switch (ds_proto) {
+ case XPRT_TRANSPORT_TCP:
+ case XPRT_TRANSPORT_TCP_TLS:
+ if (mds_clp->cl_nconnect > 1)
+ cl_init.nconnect = mds_clp->cl_nconnect;
+ }
if (mds_srv->flags & NFS_MOUNT_NORESVPORT)
__set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c
index 75ed8354576b..321854942ce1 100644
--- a/fs/nfs/nfs4client.c
+++ b/fs/nfs/nfs4client.c
@@ -918,8 +918,11 @@ static int nfs4_set_client(struct nfs_server *server,
__set_bit(NFS_CS_REUSEPORT, &cl_init.init_flags);
else
cl_init.max_connect = max_connect;
- if (proto == XPRT_TRANSPORT_TCP)
+ switch (proto) {
+ case XPRT_TRANSPORT_TCP:
+ case XPRT_TRANSPORT_TCP_TLS:
cl_init.nconnect = nconnect;
+ }
if (server->flags & NFS_MOUNT_NORESVPORT)
__set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
@@ -988,9 +991,13 @@ struct nfs_client *nfs4_set_ds_client(struct nfs_server *mds_srv,
return ERR_PTR(-EINVAL);
cl_init.hostname = buf;
- if (mds_clp->cl_nconnect > 1 && ds_proto == XPRT_TRANSPORT_TCP) {
- cl_init.nconnect = mds_clp->cl_nconnect;
- cl_init.max_connect = NFS_MAX_TRANSPORTS;
+ switch (ds_proto) {
+ case XPRT_TRANSPORT_TCP:
+ case XPRT_TRANSPORT_TCP_TLS:
+ if (mds_clp->cl_nconnect > 1) {
+ cl_init.nconnect = mds_clp->cl_nconnect;
+ cl_init.max_connect = NFS_MAX_TRANSPORTS;
+ }
}
if (mds_srv->flags & NFS_MOUNT_NORESVPORT)
@@ -1130,9 +1137,6 @@ static int nfs4_server_common_setup(struct nfs_server *server,
static int nfs4_init_server(struct nfs_server *server, struct fs_context *fc)
{
struct nfs_fs_context *ctx = nfs_fc2context(fc);
- struct xprtsec_parms xprtsec = {
- .policy = RPC_XPRTSEC_NONE,
- };
struct rpc_timeout timeparms;
int error;
@@ -1164,7 +1168,7 @@ static int nfs4_init_server(struct nfs_server *server, struct fs_context *fc)
ctx->nfs_server.nconnect,
ctx->nfs_server.max_connect,
fc->net_ns,
- &xprtsec);
+ &ctx->xprtsec);
if (error < 0)
return error;
@@ -1226,8 +1230,8 @@ struct nfs_server *nfs4_create_referral_server(struct fs_context *fc)
struct nfs_fs_context *ctx = nfs_fc2context(fc);
struct nfs_client *parent_client;
struct nfs_server *server, *parent_server;
+ int proto, error;
bool auth_probe;
- int error;
server = nfs_alloc_server();
if (!server)
@@ -1260,13 +1264,16 @@ struct nfs_server *nfs4_create_referral_server(struct fs_context *fc)
goto init_server;
#endif /* IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA) */
+ proto = XPRT_TRANSPORT_TCP;
+ if (parent_client->cl_xprtsec.policy != RPC_XPRTSEC_NONE)
+ proto = XPRT_TRANSPORT_TCP_TLS;
rpc_set_port(&ctx->nfs_server.address, NFS_PORT);
error = nfs4_set_client(server,
ctx->nfs_server.hostname,
&ctx->nfs_server._address,
ctx->nfs_server.addrlen,
parent_client->cl_ipaddr,
- XPRT_TRANSPORT_TCP,
+ proto,
parent_server->client->cl_timeout,
parent_client->cl_mvops->minor_version,
parent_client->cl_nconnect,
@@ -1323,6 +1330,7 @@ int nfs4_update_server(struct nfs_server *server, const char *hostname,
.dstaddr = (struct sockaddr *)sap,
.addrlen = salen,
.servername = hostname,
+ /* cel: bleh. We might need to pass TLS parameters here */
};
char buf[INET6_ADDRSTRLEN + 1];
struct sockaddr_storage address;
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 30e53e93049e..059b0beabc1b 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -59,6 +59,8 @@
#include <linux/uaccess.h>
#include <linux/nfs_ssc.h>
+#include <uapi/linux/tls.h>
+
#include "nfs4_fs.h"
#include "callback.h"
#include "delegation.h"
@@ -491,6 +493,16 @@ static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
+ switch (clp->cl_xprtsec.policy) {
+ case RPC_XPRTSEC_TLS_ANON:
+ seq_puts(m, ",xprtsec=tls");
+ break;
+ case RPC_XPRTSEC_TLS_X509:
+ seq_puts(m, ",xprtsec=mtls");
+ break;
+ default:
+ break;
+ }
if (version != 4)
nfs_show_mountd_options(m, nfss, showdefaults);
