diff options
Diffstat (limited to 'fs/lockd/clntxdr.c')
| -rw-r--r-- | fs/lockd/clntxdr.c | 627 |
1 files changed, 627 insertions, 0 deletions
diff --git a/fs/lockd/clntxdr.c b/fs/lockd/clntxdr.c new file mode 100644 index 000000000000..180ac34feb9a --- /dev/null +++ b/fs/lockd/clntxdr.c @@ -0,0 +1,627 @@ +/* + * linux/fs/lockd/clntxdr.c + * + * XDR functions to encode/decode NLM version 3 RPC arguments and results. + * NLM version 3 is backwards compatible with NLM versions 1 and 2. + * + * NLM client-side only. + * + * Copyright (C) 2010, Oracle. All rights reserved. + */ + +#include <linux/types.h> +#include <linux/sunrpc/xdr.h> +#include <linux/sunrpc/clnt.h> +#include <linux/sunrpc/stats.h> +#include <linux/lockd/lockd.h> + +#define NLMDBG_FACILITY NLMDBG_XDR + +#if (NLMCLNT_OHSIZE > XDR_MAX_NETOBJ) +# error "NLM host name cannot be larger than XDR_MAX_NETOBJ!" +#endif + +/* + * Declare the space requirements for NLM arguments and replies as + * number of 32bit-words + */ +#define NLM_cookie_sz (1+(NLM_MAXCOOKIELEN>>2)) +#define NLM_caller_sz (1+(NLMCLNT_OHSIZE>>2)) +#define NLM_owner_sz (1+(NLMCLNT_OHSIZE>>2)) +#define NLM_fhandle_sz (1+(NFS2_FHSIZE>>2)) +#define NLM_lock_sz (3+NLM_caller_sz+NLM_owner_sz+NLM_fhandle_sz) +#define NLM_holder_sz (4+NLM_owner_sz) + +#define NLM_testargs_sz (NLM_cookie_sz+1+NLM_lock_sz) +#define NLM_lockargs_sz (NLM_cookie_sz+4+NLM_lock_sz) +#define NLM_cancargs_sz (NLM_cookie_sz+2+NLM_lock_sz) +#define NLM_unlockargs_sz (NLM_cookie_sz+NLM_lock_sz) + +#define NLM_testres_sz (NLM_cookie_sz+1+NLM_holder_sz) +#define NLM_res_sz (NLM_cookie_sz+1) +#define NLM_norep_sz (0) + + +static s32 loff_t_to_s32(loff_t offset) +{ + s32 res; + + if (offset >= NLM_OFFSET_MAX) + res = NLM_OFFSET_MAX; + else if (offset <= -NLM_OFFSET_MAX) + res = -NLM_OFFSET_MAX; + else + res = offset; + return res; +} + +static void nlm_compute_offsets(const struct nlm_lock *lock, + u32 *l_offset, u32 *l_len) +{ + const struct file_lock *fl = &lock->fl; + + BUG_ON(fl->fl_start > NLM_OFFSET_MAX); + BUG_ON(fl->fl_end > NLM_OFFSET_MAX && + fl->fl_end != OFFSET_MAX); + + *l_offset = loff_t_to_s32(fl->fl_start); + if (fl->fl_end == OFFSET_MAX) + *l_len = 0; + else + *l_len = loff_t_to_s32(fl->fl_end - fl->fl_start + 1); +} + +/* + * Handle decode buffer overflows out-of-line. + */ +static void print_overflow_msg(const char *func, const struct xdr_stream *xdr) +{ + dprintk("lockd: %s prematurely hit the end of our receive buffer. " + "Remaining buffer length is %tu words.\n", + func, xdr->end - xdr->p); +} + + +/* + * Encode/decode NLMv3 basic data types + * + * Basic NLMv3 data types are not defined in an IETF standards + * document. X/Open has a description of these data types that + * is useful. See Chapter 10 of "Protocols for Interworking: + * XNFS, Version 3W". + * + * Not all basic data types have their own encoding and decoding + * functions. For run-time efficiency, some data types are encoded + * or decoded inline. + */ + +static void encode_bool(struct xdr_stream *xdr, const int value) +{ + __be32 *p; + + p = xdr_reserve_space(xdr, 4); + *p = value ? xdr_one : xdr_zero; +} + +static void encode_int32(struct xdr_stream *xdr, const s32 value) +{ + __be32 *p; + + p = xdr_reserve_space(xdr, 4); + *p = cpu_to_be32(value); +} + +/* + * typedef opaque netobj<MAXNETOBJ_SZ> + */ +static void encode_netobj(struct xdr_stream *xdr, + const u8 *data, const unsigned int length) +{ + __be32 *p; + + BUG_ON(length > XDR_MAX_NETOBJ); + p = xdr_reserve_space(xdr, 4 + length); + xdr_encode_opaque(p, data, length); +} + +static int decode_netobj(struct xdr_stream *xdr, + struct xdr_netobj *obj) +{ + u32 length; + __be32 *p; + + p = xdr_inline_decode(xdr, 4); + if (unlikely(p == NULL)) + goto out_overflow; + length = be32_to_cpup(p++); + if (unlikely(length > XDR_MAX_NETOBJ)) + goto out_size; + obj->len = length; + obj->data = (u8 *)p; + return 0; +out_size: + dprintk("NFS: returned netobj was too long: %u\n", length); + return -EIO; +out_overflow: + print_overflow_msg(__func__, xdr); + return -EIO; +} + +/* + * netobj cookie; + */ +static void encode_cookie(struct xdr_stream *xdr, + const struct nlm_cookie *cookie) +{ + BUG_ON(cookie->len > NLM_MAXCOOKIELEN); + encode_netobj(xdr, (u8 *)&cookie->data, cookie->len); +} + +static int decode_cookie(struct xdr_stream *xdr, + struct nlm_cookie *cookie) +{ + u32 length; + __be32 *p; + + p = xdr_inline_decode(xdr, 4); + if (unlikely(p == NULL)) + goto out_overflow; + length = be32_to_cpup(p++); + /* apparently HPUX can return empty cookies */ + if (length == 0) + goto out_hpux; + if (length > NLM_MAXCOOKIELEN) + goto out_size; + p = xdr_inline_decode(xdr, length); + if (unlikely(p == NULL)) + goto out_overflow; + cookie->len = length; + memcpy(cookie->data, p, length); + return 0; +out_hpux: + cookie->len = 4; + memset(cookie->data, 0, 4); + return 0; +out_size: + dprintk("NFS: returned cookie was too long: %u\n", length); + return -EIO; +out_overflow: + print_overflow_msg(__func__, xdr); + return -EIO; +} + +/* + * netobj fh; + */ +static void encode_fh(struct xdr_stream *xdr, const struct nfs_fh *fh) +{ + BUG_ON(fh->size != NFS2_FHSIZE); + encode_netobj(xdr, (u8 *)&fh->data, NFS2_FHSIZE); +} + +/* + * enum nlm_stats { + * LCK_GRANTED = 0, + * LCK_DENIED = 1, + * LCK_DENIED_NOLOCKS = 2, + * LCK_BLOCKED = 3, + * LCK_DENIED_GRACE_PERIOD = 4 + * }; + * + * + * struct nlm_stat { + * nlm_stats stat; + * }; + * + * NB: we don't swap bytes for the NLM status values. The upper + * layers deal directly with the status value in network byte + * order. + */ + +static void encode_nlm_stat(struct xdr_stream *xdr, + const __be32 stat) +{ + __be32 *p; + + BUG_ON(be32_to_cpu(stat) > NLM_LCK_DENIED_GRACE_PERIOD); + p = xdr_reserve_space(xdr, 4); + *p = stat; +} + +static int decode_nlm_stat(struct xdr_stream *xdr, + __be32 *stat) +{ + __be32 *p; + + p = xdr_inline_decode(xdr, 4); + if (unlikely(p == NULL)) + goto out_overflow; + if (unlikely(*p > nlm_lck_denied_grace_period)) + goto out_enum; + *stat = *p; + return 0; +out_enum: + dprintk("%s: server returned invalid nlm_stats value: %u\n", + __func__, be32_to_cpup(p)); + return -EIO; +out_overflow: + print_overflow_msg(__func__, xdr); + return -EIO; +} + +/* + * struct nlm_holder { + * bool exclusive; + * int uppid; + * netobj oh; + * unsigned l_offset; + * unsigned l_len; + * }; + */ +static void encode_nlm_holder(struct xdr_stream *xdr, + const struct nlm_res *result) +{ + const struct nlm_lock *lock = &result->lock; + u32 l_offset, l_len; + __be32 *p; + + encode_bool(xdr, lock->fl.fl_type == F_RDLCK); + encode_int32(xdr, lock->svid); + encode_netobj(xdr, lock->oh.data, lock->oh.len); + + p = xdr_reserve_space(xdr, 4 + 4); + nlm_compute_offsets(lock, &l_offset, &l_len); + *p++ = cpu_to_be32(l_offset); + *p = cpu_to_be32(l_len); +} + +static int decode_nlm_holder(struct xdr_stream *xdr, struct nlm_res *result) +{ + struct nlm_lock *lock = &result->lock; + struct file_lock *fl = &lock->fl; + u32 exclusive, l_offset, l_len; + int error; + __be32 *p; + s32 end; + + memset(lock, 0, sizeof(*lock)); + locks_init_lock(fl); + + p = xdr_inline_decode(xdr, 4 + 4); + if (unlikely(p == NULL)) + goto out_overflow; + exclusive = be32_to_cpup(p++); + lock->svid = be32_to_cpup(p); + fl->fl_pid = (pid_t)lock->svid; + + error = decode_netobj(xdr, &lock->oh); + if (unlikely(error)) + goto out; + + p = xdr_inline_decode(xdr, 4 + 4); + if (unlikely(p == NULL)) + goto out_overflow; + + fl->fl_flags = FL_POSIX; + fl->fl_type = exclusive != 0 ? F_WRLCK : F_RDLCK; + l_offset = be32_to_cpup(p++); + l_len = be32_to_cpup(p); + end = l_offset + l_len - 1; + + fl->fl_start = (loff_t)l_offset; + if (l_len == 0 || end < 0) + fl->fl_end = OFFSET_MAX; + else + fl->fl_end = (loff_t)end; + error = 0; +out: + return error; +out_overflow: + print_overflow_msg(__func__, xdr); + return -EIO; +} + +/* + * string caller_name<LM_MAXSTRLEN>; + */ +static void encode_caller_name(struct xdr_stream *xdr, const char *name) +{ + /* NB: client-side does not set lock->len */ + u32 length = strlen(name); + __be32 *p; + + BUG_ON(length > NLM_MAXSTRLEN); + p = xdr_reserve_space(xdr, 4 + length); + xdr_encode_opaque(p, name, length); +} + +/* + * struct nlm_lock { + * string caller_name<LM_MAXSTRLEN>; + * netobj fh; + * netobj oh; + * int uppid; + * unsigned l_offset; + * unsigned l_len; + * }; + */ +static void encode_nlm_lock(struct xdr_stream *xdr, + const struct nlm_lock *lock) +{ + u32 l_offset, l_len; + __be32 *p; + + encode_caller_name(xdr, lock->caller); + encode_fh(xdr, &lock->fh); + encode_netobj(xdr, lock->oh.data, lock->oh.len); + + p = xdr_reserve_space(xdr, 4 + 4 + 4); + *p++ = cpu_to_be32(lock->svid); + + nlm_compute_offsets(lock, &l_offset, &l_len); + *p++ = cpu_to_be32(l_offset); + *p = cpu_to_be32(l_len); +} + + +/* + * NLMv3 XDR encode functions + * + * NLMv3 argument types are defined in Chapter 10 of The Open Group's + * "Protocols for Interworking: XNFS, Version 3W". + */ + +/* + * struct nlm_testargs { + * netobj cookie; + * bool exclusive; + * struct nlm_lock alock; + * }; + */ +static void nlm_xdr_enc_testargs(struct rpc_rqst *req, + struct xdr_stream *xdr, + const struct nlm_args *args) +{ + const struct nlm_lock *lock = &args->lock; + + encode_cookie(xdr, &args->cookie); + encode_bool(xdr, lock->fl.fl_type == F_WRLCK); + encode_nlm_lock(xdr, lock); +} + +/* + * struct nlm_lockargs { + * netobj cookie; + * bool block; + * bool exclusive; + * struct nlm_lock alock; + * bool reclaim; + * int state; + * }; + */ +static void nlm_xdr_enc_lockargs(struct rpc_rqst *req, + struct xdr_stream *xdr, + const struct nlm_args *args) +{ + const struct nlm_lock *lock = &args->lock; + + encode_cookie(xdr, &args->cookie); + encode_bool(xdr, args->block); + encode_bool(xdr, lock->fl.fl_type == F_WRLCK); + encode_nlm_lock(xdr, lock); + encode_bool(xdr, args->reclaim); + encode_int32(xdr, args->state); +} + +/* + * struct nlm_cancargs { + * netobj cookie; + * bool block; + * bool exclusive; + * struct nlm_lock alock; + * }; + */ +static void nlm_xdr_enc_cancargs(struct rpc_rqst *req, + struct xdr_stream *xdr, + const struct nlm_args *args) +{ + const struct nlm_lock *lock = &args->lock; + + encode_cookie(xdr, &args->cookie); + encode_bool(xdr, args->block); + encode_bool(xdr, lock->fl.fl_type == F_WRLCK); + encode_nlm_lock(xdr, lock); +} + +/* + * struct nlm_unlockargs { + * netobj cookie; + * struct nlm_lock alock; + * }; + */ +static void nlm_xdr_enc_unlockargs(struct rpc_rqst *req, + struct xdr_stream *xdr, + const struct nlm_args *args) +{ + const struct nlm_lock *lock = &args->lock; + + encode_cookie(xdr, &args->cookie); + encode_nlm_lock(xdr, lock); +} + +/* + * struct nlm_res { + * netobj cookie; + * nlm_stat stat; + * }; + */ +static void nlm_xdr_enc_res(struct rpc_rqst *req, + struct xdr_stream *xdr, + const struct nlm_res *result) +{ + encode_cookie(xdr, &result->cookie); + encode_nlm_stat(xdr, result->status); +} + +/* + * union nlm_testrply switch (nlm_stats stat) { + * case LCK_DENIED: + * struct nlm_holder holder; + * default: + * void; + * }; + * + * struct nlm_testres { + * netobj cookie; + * nlm_testrply test_stat; + * }; + */ +static void encode_nlm_testrply(struct xdr_stream *xdr, + const struct nlm_res *result) +{ + if (result->status == nlm_lck_denied) + encode_nlm_holder(xdr, result); +} + +static void nlm_xdr_enc_testres(struct rpc_rqst *req, + struct xdr_stream *xdr, + const struct nlm_res *result) +{ + encode_cookie(xdr, &result->cookie); + encode_nlm_stat(xdr, result->status); + encode_nlm_testrply(xdr, result); +} + + +/* + * NLMv3 XDR decode functions + * + * NLMv3 result types are defined in Chapter 10 of The Open Group's + * "Protocols for Interworking: XNFS, Version 3W". + */ + +/* + * union nlm_testrply switch (nlm_stats stat) { + * case LCK_DENIED: + * struct nlm_holder holder; + * default: + * void; + * }; + * + * struct nlm_testres { + * netobj cookie; + * nlm_testrply test_stat; + * }; + */ +static int decode_nlm_testrply(struct xdr_stream *xdr, + struct nlm_res *result) +{ + int error; + + error = decode_nlm_stat(xdr, &result->status); + if (unlikely(error)) + goto out; + if (result->status == nlm_lck_denied) + error = decode_nlm_holder(xdr, result); +out: + return error; +} + +static int nlm_xdr_dec_testres(struct rpc_rqst *req, + struct xdr_stream *xdr, + struct nlm_res *result) +{ + int error; + + error = decode_cookie(xdr, &result->cookie); + if (unlikely(error)) + goto out; + error = decode_nlm_testrply(xdr, result); +out: + return error; +} + +/* + * struct nlm_res { + * netobj cookie; + * nlm_stat stat; + * }; + */ +static int nlm_xdr_dec_res(struct rpc_rqst *req, + struct xdr_stream *xdr, + struct nlm_res *result) +{ + int error; + + error = decode_cookie(xdr, &result->cookie); + if (unlikely(error)) + goto out; + error = decode_nlm_stat(xdr, &result->status); +out: + return error; +} + + +/* + * For NLM, a void procedure really returns nothing + */ +#define nlm_xdr_dec_norep NULL + +#define PROC(proc, argtype, restype) \ +[NLMPROC_##proc] = { \ + .p_proc = NLMPROC_##proc, \ + .p_encode = (kxdreproc_t)nlm_xdr_enc_##argtype, \ + .p_decode = (kxdrdproc_t)nlm_xdr_dec_##restype, \ + .p_arglen = NLM_##argtype##_sz, \ + .p_replen = NLM_##restype##_sz, \ + .p_statidx = NLMPROC_##proc, \ + .p_name = #proc, \ + } + +static struct rpc_procinfo nlm_procedures[] = { + PROC(TEST, testargs, testres), + PROC(LOCK, lockargs, res), + PROC(CANCEL, cancargs, res), + PROC(UNLOCK, unlockargs, res), + PROC(GRANTED, testargs, res), + PROC(TEST_MSG, testargs, norep), + PROC(LOCK_MSG, lockargs, norep), + PROC(CANCEL_MSG, cancargs, norep), + PROC(UNLOCK_MSG, unlockargs, norep), + PROC(GRANTED_MSG, testargs, norep), + PROC(TEST_RES, testres, norep), + PROC(LOCK_RES, res, norep), + PROC(CANCEL_RES, res, norep), + PROC(UNLOCK_RES, res, norep), + PROC(GRANTED_RES, res, norep), +}; + +static struct rpc_version nlm_version1 = { + .number = 1, + .nrprocs = ARRAY_SIZE(nlm_procedures), + .procs = nlm_procedures, +}; + +static struct rpc_version nlm_version3 = { + .number = 3, + .nrprocs = ARRAY_SIZE(nlm_procedures), + .procs = nlm_procedures, +}; + +static struct rpc_version *nlm_versions[] = { + [1] = &nlm_version1, + [3] = &nlm_version3, +#ifdef CONFIG_LOCKD_V4 + [4] = &nlm_version4, +#endif +}; + +static struct rpc_stat nlm_rpc_stats; + +struct rpc_program nlm_program = { + .name = "lockd", + .number = NLM_PROGRAM, + .nrvers = ARRAY_SIZE(nlm_versions), + .version = nlm_versions, + .stats = &nlm_rpc_stats, +}; |