The LOCALIO auxiliary RPC protocol consists of a single "UUID_IS_LOCAL" RPC method that allows the Linux NFS client to verify the local Linux NFS server can see the nonce (single-use UUID) the client generated and made available in nfs_common. This protocol isn't part of an IETF standard, nor does it need to be considering it is Linux-to-Linux auxiliary RPC protocol that amounts to an implementation detail. The UUID_IS_LOCAL method encodes the client generated uuid_t in terms of the fixed UUID_SIZE (16 bytes). The fixed size opaque encode and decode XDR methods are used instead of the less efficient variable sized methods. The RPC program number for the NFS_LOCALIO_PROGRAM is 400122 (as assigned by IANA, see https://www.iana.org/assignments/rpc-program-numbers/ ): Linux Kernel Organization 400122 nfslocalio Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx> [neilb: factored out and simplified single localio protocol] Co-developed-by: NeilBrown <neil@xxxxxxxxxx> Signed-off-by: NeilBrown <neil@xxxxxxxxxx> --- fs/nfsd/localio.c | 75 +++++++++++++++++++++++++++++++++++++++++++++ fs/nfsd/nfsd.h | 4 +++ fs/nfsd/nfssvc.c | 23 +++++++++++++- include/linux/nfs.h | 7 +++++ 4 files changed, 108 insertions(+), 1 deletion(-) diff --git a/fs/nfsd/localio.c b/fs/nfsd/localio.c index 8e0cce835f81..2ceab49f3cb6 100644 --- a/fs/nfsd/localio.c +++ b/fs/nfsd/localio.c @@ -13,12 +13,15 @@ #include <linux/nfs.h> #include <linux/nfs_common.h> #include <linux/nfslocalio.h> +#include <linux/nfs_fs.h> +#include <linux/nfs_xdr.h> #include <linux/string.h> #include "nfsd.h" #include "vfs.h" #include "netns.h" #include "filecache.h" +#include "cache.h" /** * nfsd_open_local_fh - lookup a local filehandle @nfs_fh and map to @file @@ -106,3 +109,75 @@ EXPORT_SYMBOL_GPL(nfsd_open_local_fh); /* Compile time type checking, not used by anything */ static nfs_to_nfsd_open_local_fh_t __maybe_unused nfsd_open_local_fh_typecheck = nfsd_open_local_fh; + +/* + * UUID_IS_LOCAL XDR functions + */ + +static __be32 localio_proc_null(struct svc_rqst *rqstp) +{ + return rpc_success; +} + +struct localio_uuidarg { + uuid_t uuid; +}; + +static __be32 localio_proc_uuid_is_local(struct svc_rqst *rqstp) +{ + struct localio_uuidarg *argp = rqstp->rq_argp; + + (void) nfs_uuid_is_local(&argp->uuid, SVC_NET(rqstp), + rqstp->rq_client); + + return rpc_success; +} + +static bool localio_decode_uuidarg(struct svc_rqst *rqstp, + struct xdr_stream *xdr) +{ + struct localio_uuidarg *argp = rqstp->rq_argp; + u8 uuid[UUID_SIZE]; + + if (decode_opaque_fixed(xdr, uuid, UUID_SIZE)) + return false; + import_uuid(&argp->uuid, uuid); + + return true; +} + +static const struct svc_procedure localio_procedures1[] = { + [LOCALIOPROC_NULL] = { + .pc_func = localio_proc_null, + .pc_decode = nfssvc_decode_voidarg, + .pc_encode = nfssvc_encode_voidres, + .pc_argsize = sizeof(struct nfsd_voidargs), + .pc_ressize = sizeof(struct nfsd_voidres), + .pc_cachetype = RC_NOCACHE, + .pc_xdrressize = 0, + .pc_name = "NULL", + }, + [LOCALIOPROC_UUID_IS_LOCAL] = { + .pc_func = localio_proc_uuid_is_local, + .pc_decode = localio_decode_uuidarg, + .pc_encode = nfssvc_encode_voidres, + .pc_argsize = sizeof(struct localio_uuidarg), + .pc_argzero = sizeof(struct localio_uuidarg), + .pc_ressize = sizeof(struct nfsd_voidres), + .pc_cachetype = RC_NOCACHE, + .pc_name = "UUID_IS_LOCAL", + }, +}; + +#define LOCALIO_NR_PROCEDURES ARRAY_SIZE(localio_procedures1) +static DEFINE_PER_CPU_ALIGNED(unsigned long, + localio_count[LOCALIO_NR_PROCEDURES]); +const struct svc_version localio_version1 = { + .vs_vers = 1, + .vs_nproc = LOCALIO_NR_PROCEDURES, + .vs_proc = localio_procedures1, + .vs_dispatch = nfsd_dispatch, + .vs_count = localio_count, + .vs_xdrsize = XDR_QUADLEN(UUID_SIZE), + .vs_hidden = true, +}; diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h index b0d3e82d6dcd..232a873dc53a 100644 --- a/fs/nfsd/nfsd.h +++ b/fs/nfsd/nfsd.h @@ -146,6 +146,10 @@ extern const struct svc_version nfsd_acl_version3; #endif #endif +#if IS_ENABLED(CONFIG_NFSD_LOCALIO) +extern const struct svc_version localio_version1; +#endif + struct nfsd_net; enum vers_op {NFSD_SET, NFSD_CLEAR, NFSD_TEST, NFSD_AVAIL }; diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c index c639fbe4d8c2..5f8680ab1013 100644 --- a/fs/nfsd/nfssvc.c +++ b/fs/nfsd/nfssvc.c @@ -79,6 +79,15 @@ DEFINE_SPINLOCK(nfsd_drc_lock); unsigned long nfsd_drc_max_mem; unsigned long nfsd_drc_mem_used; +#if IS_ENABLED(CONFIG_NFSD_LOCALIO) +static const struct svc_version *localio_versions[] = { + [1] = &localio_version1, +}; + +#define NFSD_LOCALIO_NRVERS ARRAY_SIZE(localio_versions) + +#endif /* CONFIG_NFSD_LOCALIO */ + #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) static const struct svc_version *nfsd_acl_version[] = { # if defined(CONFIG_NFSD_V2_ACL) @@ -127,6 +136,18 @@ struct svc_program nfsd_programs[] = { .pg_rpcbind_set = nfsd_acl_rpcbind_set, }, #endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */ +#if IS_ENABLED(CONFIG_NFSD_LOCALIO) + { + .pg_prog = NFS_LOCALIO_PROGRAM, + .pg_nvers = NFSD_LOCALIO_NRVERS, + .pg_vers = localio_versions, + .pg_name = "nfslocalio", + .pg_class = "nfsd", + .pg_authenticate = svc_set_client, + .pg_init_request = svc_generic_init_request, + .pg_rpcbind_set = svc_generic_rpcbind_set, + } +#endif /* IS_ENABLED(CONFIG_NFSD_LOCALIO) */ }; bool nfsd_support_version(int vers) @@ -944,7 +965,7 @@ nfsd(void *vrqstp) } /** - * nfsd_dispatch - Process an NFS or NFSACL Request + * nfsd_dispatch - Process an NFS or NFSACL or LOCALIO Request * @rqstp: incoming request * * This RPC dispatcher integrates the NFS server's duplicate reply cache. diff --git a/include/linux/nfs.h b/include/linux/nfs.h index ceb70a926b95..5ff1a5b3b00c 100644 --- a/include/linux/nfs.h +++ b/include/linux/nfs.h @@ -13,6 +13,13 @@ #include <linux/crc32.h> #include <uapi/linux/nfs.h> +/* The localio program is entirely private to Linux and is + * NOT part of the uapi. + */ +#define NFS_LOCALIO_PROGRAM 400122 +#define LOCALIOPROC_NULL 0 +#define LOCALIOPROC_UUID_IS_LOCAL 1 + /* * This is the kernel NFS client file handle representation */ -- 2.44.0
