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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /fs/nfs/mount_clnt.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/nfs/mount_clnt.c')
-rw-r--r-- | fs/nfs/mount_clnt.c | 544 |
1 files changed, 544 insertions, 0 deletions
diff --git a/fs/nfs/mount_clnt.c b/fs/nfs/mount_clnt.c new file mode 100644 index 000000000..68e76b626 --- /dev/null +++ b/fs/nfs/mount_clnt.c @@ -0,0 +1,544 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * In-kernel MOUNT protocol client + * + * Copyright (C) 1997, Olaf Kirch <okir@monad.swb.de> + */ + +#include <linux/types.h> +#include <linux/socket.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/uio.h> +#include <linux/net.h> +#include <linux/in.h> +#include <linux/sunrpc/clnt.h> +#include <linux/sunrpc/sched.h> +#include <linux/nfs_fs.h> +#include "internal.h" + +#define NFSDBG_FACILITY NFSDBG_MOUNT + +/* + * Defined by RFC 1094, section A.3; and RFC 1813, section 5.1.4 + */ +#define MNTPATHLEN (1024) + +/* + * XDR data type sizes + */ +#define encode_dirpath_sz (1 + XDR_QUADLEN(MNTPATHLEN)) +#define MNT_status_sz (1) +#define MNT_fhandle_sz XDR_QUADLEN(NFS2_FHSIZE) +#define MNT_fhandlev3_sz XDR_QUADLEN(NFS3_FHSIZE) +#define MNT_authflav3_sz (1 + NFS_MAX_SECFLAVORS) + +/* + * XDR argument and result sizes + */ +#define MNT_enc_dirpath_sz encode_dirpath_sz +#define MNT_dec_mountres_sz (MNT_status_sz + MNT_fhandle_sz) +#define MNT_dec_mountres3_sz (MNT_status_sz + MNT_fhandlev3_sz + \ + MNT_authflav3_sz) + +/* + * Defined by RFC 1094, section A.5 + */ +enum { + MOUNTPROC_NULL = 0, + MOUNTPROC_MNT = 1, + MOUNTPROC_DUMP = 2, + MOUNTPROC_UMNT = 3, + MOUNTPROC_UMNTALL = 4, + MOUNTPROC_EXPORT = 5, +}; + +/* + * Defined by RFC 1813, section 5.2 + */ +enum { + MOUNTPROC3_NULL = 0, + MOUNTPROC3_MNT = 1, + MOUNTPROC3_DUMP = 2, + MOUNTPROC3_UMNT = 3, + MOUNTPROC3_UMNTALL = 4, + MOUNTPROC3_EXPORT = 5, +}; + +static const struct rpc_program mnt_program; + +/* + * Defined by OpenGroup XNFS Version 3W, chapter 8 + */ +enum mountstat { + MNT_OK = 0, + MNT_EPERM = 1, + MNT_ENOENT = 2, + MNT_EACCES = 13, + MNT_EINVAL = 22, +}; + +static struct { + u32 status; + int errno; +} mnt_errtbl[] = { + { .status = MNT_OK, .errno = 0, }, + { .status = MNT_EPERM, .errno = -EPERM, }, + { .status = MNT_ENOENT, .errno = -ENOENT, }, + { .status = MNT_EACCES, .errno = -EACCES, }, + { .status = MNT_EINVAL, .errno = -EINVAL, }, +}; + +/* + * Defined by RFC 1813, section 5.1.5 + */ +enum mountstat3 { + MNT3_OK = 0, /* no error */ + MNT3ERR_PERM = 1, /* Not owner */ + MNT3ERR_NOENT = 2, /* No such file or directory */ + MNT3ERR_IO = 5, /* I/O error */ + MNT3ERR_ACCES = 13, /* Permission denied */ + MNT3ERR_NOTDIR = 20, /* Not a directory */ + MNT3ERR_INVAL = 22, /* Invalid argument */ + MNT3ERR_NAMETOOLONG = 63, /* Filename too long */ + MNT3ERR_NOTSUPP = 10004, /* Operation not supported */ + MNT3ERR_SERVERFAULT = 10006, /* A failure on the server */ +}; + +static struct { + u32 status; + int errno; +} mnt3_errtbl[] = { + { .status = MNT3_OK, .errno = 0, }, + { .status = MNT3ERR_PERM, .errno = -EPERM, }, + { .status = MNT3ERR_NOENT, .errno = -ENOENT, }, + { .status = MNT3ERR_IO, .errno = -EIO, }, + { .status = MNT3ERR_ACCES, .errno = -EACCES, }, + { .status = MNT3ERR_NOTDIR, .errno = -ENOTDIR, }, + { .status = MNT3ERR_INVAL, .errno = -EINVAL, }, + { .status = MNT3ERR_NAMETOOLONG, .errno = -ENAMETOOLONG, }, + { .status = MNT3ERR_NOTSUPP, .errno = -ENOTSUPP, }, + { .status = MNT3ERR_SERVERFAULT, .errno = -EREMOTEIO, }, +}; + +struct mountres { + int errno; + struct nfs_fh *fh; + unsigned int *auth_count; + rpc_authflavor_t *auth_flavors; +}; + +struct mnt_fhstatus { + u32 status; + struct nfs_fh *fh; +}; + +/** + * nfs_mount - Obtain an NFS file handle for the given host and path + * @info: pointer to mount request arguments + * @timeo: deciseconds the mount waits for a response before it retries + * @retrans: number of times the mount retries a request + * + * Uses timeout parameters specified by caller. On successful return, the + * auth_flavs list and auth_flav_len will be populated with the list from the + * server or a faked-up list if the server didn't provide one. + */ +int nfs_mount(struct nfs_mount_request *info, int timeo, int retrans) +{ + struct rpc_timeout mnt_timeout; + struct mountres result = { + .fh = info->fh, + .auth_count = info->auth_flav_len, + .auth_flavors = info->auth_flavs, + }; + struct rpc_message msg = { + .rpc_argp = info->dirpath, + .rpc_resp = &result, + }; + struct rpc_create_args args = { + .net = info->net, + .protocol = info->protocol, + .address = (struct sockaddr *)info->sap, + .addrsize = info->salen, + .timeout = &mnt_timeout, + .servername = info->hostname, + .program = &mnt_program, + .version = info->version, + .authflavor = RPC_AUTH_UNIX, + .cred = current_cred(), + }; + struct rpc_clnt *mnt_clnt; + int status; + + dprintk("NFS: sending MNT request for %s:%s\n", + (info->hostname ? info->hostname : "server"), + info->dirpath); + + if (strlen(info->dirpath) > MNTPATHLEN) + return -ENAMETOOLONG; + + if (info->noresvport) + args.flags |= RPC_CLNT_CREATE_NONPRIVPORT; + + nfs_init_timeout_values(&mnt_timeout, info->protocol, timeo, retrans); + mnt_clnt = rpc_create(&args); + if (IS_ERR(mnt_clnt)) + goto out_clnt_err; + + if (info->version == NFS_MNT3_VERSION) + msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC3_MNT]; + else + msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC_MNT]; + + status = rpc_call_sync(mnt_clnt, &msg, RPC_TASK_SOFT|RPC_TASK_TIMEOUT); + rpc_shutdown_client(mnt_clnt); + + if (status < 0) + goto out_call_err; + if (result.errno != 0) + goto out_mnt_err; + + dprintk("NFS: MNT request succeeded\n"); + status = 0; + + /* + * If the server didn't provide a flavor list, allow the + * client to try any flavor. + */ + if (info->version != NFS_MNT3_VERSION || *info->auth_flav_len == 0) { + dprintk("NFS: Faking up auth_flavs list\n"); + info->auth_flavs[0] = RPC_AUTH_NULL; + *info->auth_flav_len = 1; + } +out: + return status; + +out_clnt_err: + status = PTR_ERR(mnt_clnt); + dprintk("NFS: failed to create MNT RPC client, status=%d\n", status); + goto out; + +out_call_err: + dprintk("NFS: MNT request failed, status=%d\n", status); + goto out; + +out_mnt_err: + dprintk("NFS: MNT server returned result %d\n", result.errno); + status = result.errno; + goto out; +} + +/** + * nfs_umount - Notify a server that we have unmounted this export + * @info: pointer to umount request arguments + * + * MOUNTPROC_UMNT is advisory, so we set a short timeout, and always + * use UDP. + */ +void nfs_umount(const struct nfs_mount_request *info) +{ + static const struct rpc_timeout nfs_umnt_timeout = { + .to_initval = 1 * HZ, + .to_maxval = 3 * HZ, + .to_retries = 2, + }; + struct rpc_create_args args = { + .net = info->net, + .protocol = IPPROTO_UDP, + .address = (struct sockaddr *)info->sap, + .addrsize = info->salen, + .timeout = &nfs_umnt_timeout, + .servername = info->hostname, + .program = &mnt_program, + .version = info->version, + .authflavor = RPC_AUTH_UNIX, + .flags = RPC_CLNT_CREATE_NOPING, + .cred = current_cred(), + }; + struct rpc_message msg = { + .rpc_argp = info->dirpath, + }; + struct rpc_clnt *clnt; + int status; + + if (strlen(info->dirpath) > MNTPATHLEN) + return; + + if (info->noresvport) + args.flags |= RPC_CLNT_CREATE_NONPRIVPORT; + + clnt = rpc_create(&args); + if (IS_ERR(clnt)) + goto out_clnt_err; + + dprintk("NFS: sending UMNT request for %s:%s\n", + (info->hostname ? info->hostname : "server"), info->dirpath); + + if (info->version == NFS_MNT3_VERSION) + msg.rpc_proc = &clnt->cl_procinfo[MOUNTPROC3_UMNT]; + else + msg.rpc_proc = &clnt->cl_procinfo[MOUNTPROC_UMNT]; + + status = rpc_call_sync(clnt, &msg, 0); + rpc_shutdown_client(clnt); + + if (unlikely(status < 0)) + goto out_call_err; + + return; + +out_clnt_err: + dprintk("NFS: failed to create UMNT RPC client, status=%ld\n", + PTR_ERR(clnt)); + return; + +out_call_err: + dprintk("NFS: UMNT request failed, status=%d\n", status); +} + +/* + * XDR encode/decode functions for MOUNT + */ + +static void encode_mntdirpath(struct xdr_stream *xdr, const char *pathname) +{ + const u32 pathname_len = strlen(pathname); + __be32 *p; + + p = xdr_reserve_space(xdr, 4 + pathname_len); + xdr_encode_opaque(p, pathname, pathname_len); +} + +static void mnt_xdr_enc_dirpath(struct rpc_rqst *req, struct xdr_stream *xdr, + const void *dirpath) +{ + encode_mntdirpath(xdr, dirpath); +} + +/* + * RFC 1094: "A non-zero status indicates some sort of error. In this + * case, the status is a UNIX error number." This can be problematic + * if the server and client use different errno values for the same + * error. + * + * However, the OpenGroup XNFS spec provides a simple mapping that is + * independent of local errno values on the server and the client. + */ +static int decode_status(struct xdr_stream *xdr, struct mountres *res) +{ + unsigned int i; + u32 status; + __be32 *p; + + p = xdr_inline_decode(xdr, 4); + if (unlikely(p == NULL)) + return -EIO; + status = be32_to_cpup(p); + + for (i = 0; i < ARRAY_SIZE(mnt_errtbl); i++) { + if (mnt_errtbl[i].status == status) { + res->errno = mnt_errtbl[i].errno; + return 0; + } + } + + dprintk("NFS: unrecognized MNT status code: %u\n", status); + res->errno = -EACCES; + return 0; +} + +static int decode_fhandle(struct xdr_stream *xdr, struct mountres *res) +{ + struct nfs_fh *fh = res->fh; + __be32 *p; + + p = xdr_inline_decode(xdr, NFS2_FHSIZE); + if (unlikely(p == NULL)) + return -EIO; + + fh->size = NFS2_FHSIZE; + memcpy(fh->data, p, NFS2_FHSIZE); + return 0; +} + +static int mnt_xdr_dec_mountres(struct rpc_rqst *req, + struct xdr_stream *xdr, + void *data) +{ + struct mountres *res = data; + int status; + + status = decode_status(xdr, res); + if (unlikely(status != 0 || res->errno != 0)) + return status; + return decode_fhandle(xdr, res); +} + +static int decode_fhs_status(struct xdr_stream *xdr, struct mountres *res) +{ + unsigned int i; + u32 status; + __be32 *p; + + p = xdr_inline_decode(xdr, 4); + if (unlikely(p == NULL)) + return -EIO; + status = be32_to_cpup(p); + + for (i = 0; i < ARRAY_SIZE(mnt3_errtbl); i++) { + if (mnt3_errtbl[i].status == status) { + res->errno = mnt3_errtbl[i].errno; + return 0; + } + } + + dprintk("NFS: unrecognized MNT3 status code: %u\n", status); + res->errno = -EACCES; + return 0; +} + +static int decode_fhandle3(struct xdr_stream *xdr, struct mountres *res) +{ + struct nfs_fh *fh = res->fh; + u32 size; + __be32 *p; + + p = xdr_inline_decode(xdr, 4); + if (unlikely(p == NULL)) + return -EIO; + + size = be32_to_cpup(p); + if (size > NFS3_FHSIZE || size == 0) + return -EIO; + + p = xdr_inline_decode(xdr, size); + if (unlikely(p == NULL)) + return -EIO; + + fh->size = size; + memcpy(fh->data, p, size); + return 0; +} + +static int decode_auth_flavors(struct xdr_stream *xdr, struct mountres *res) +{ + rpc_authflavor_t *flavors = res->auth_flavors; + unsigned int *count = res->auth_count; + u32 entries, i; + __be32 *p; + + if (*count == 0) + return 0; + + p = xdr_inline_decode(xdr, 4); + if (unlikely(p == NULL)) + return -EIO; + entries = be32_to_cpup(p); + dprintk("NFS: received %u auth flavors\n", entries); + if (entries > NFS_MAX_SECFLAVORS) + entries = NFS_MAX_SECFLAVORS; + + p = xdr_inline_decode(xdr, 4 * entries); + if (unlikely(p == NULL)) + return -EIO; + + if (entries > *count) + entries = *count; + + for (i = 0; i < entries; i++) { + flavors[i] = be32_to_cpup(p++); + dprintk("NFS: auth flavor[%u]: %d\n", i, flavors[i]); + } + *count = i; + + return 0; +} + +static int mnt_xdr_dec_mountres3(struct rpc_rqst *req, + struct xdr_stream *xdr, + void *data) +{ + struct mountres *res = data; + int status; + + status = decode_fhs_status(xdr, res); + if (unlikely(status != 0 || res->errno != 0)) + return status; + status = decode_fhandle3(xdr, res); + if (unlikely(status != 0)) { + res->errno = -EBADHANDLE; + return 0; + } + return decode_auth_flavors(xdr, res); +} + +static const struct rpc_procinfo mnt_procedures[] = { + [MOUNTPROC_MNT] = { + .p_proc = MOUNTPROC_MNT, + .p_encode = mnt_xdr_enc_dirpath, + .p_decode = mnt_xdr_dec_mountres, + .p_arglen = MNT_enc_dirpath_sz, + .p_replen = MNT_dec_mountres_sz, + .p_statidx = MOUNTPROC_MNT, + .p_name = "MOUNT", + }, + [MOUNTPROC_UMNT] = { + .p_proc = MOUNTPROC_UMNT, + .p_encode = mnt_xdr_enc_dirpath, + .p_arglen = MNT_enc_dirpath_sz, + .p_statidx = MOUNTPROC_UMNT, + .p_name = "UMOUNT", + }, +}; + +static const struct rpc_procinfo mnt3_procedures[] = { + [MOUNTPROC3_MNT] = { + .p_proc = MOUNTPROC3_MNT, + .p_encode = mnt_xdr_enc_dirpath, + .p_decode = mnt_xdr_dec_mountres3, + .p_arglen = MNT_enc_dirpath_sz, + .p_replen = MNT_dec_mountres3_sz, + .p_statidx = MOUNTPROC3_MNT, + .p_name = "MOUNT", + }, + [MOUNTPROC3_UMNT] = { + .p_proc = MOUNTPROC3_UMNT, + .p_encode = mnt_xdr_enc_dirpath, + .p_arglen = MNT_enc_dirpath_sz, + .p_statidx = MOUNTPROC3_UMNT, + .p_name = "UMOUNT", + }, +}; + +static unsigned int mnt_counts[ARRAY_SIZE(mnt_procedures)]; +static const struct rpc_version mnt_version1 = { + .number = 1, + .nrprocs = ARRAY_SIZE(mnt_procedures), + .procs = mnt_procedures, + .counts = mnt_counts, +}; + +static unsigned int mnt3_counts[ARRAY_SIZE(mnt3_procedures)]; +static const struct rpc_version mnt_version3 = { + .number = 3, + .nrprocs = ARRAY_SIZE(mnt3_procedures), + .procs = mnt3_procedures, + .counts = mnt3_counts, +}; + +static const struct rpc_version *mnt_version[] = { + NULL, + &mnt_version1, + NULL, + &mnt_version3, +}; + +static struct rpc_stat mnt_stats; + +static const struct rpc_program mnt_program = { + .name = "mount", + .number = NFS_MNT_PROGRAM, + .nrvers = ARRAY_SIZE(mnt_version), + .version = mnt_version, + .stats = &mnt_stats, +}; |