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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /fs/lockd/clntxdr.c
Initial import
Diffstat (limited to 'fs/lockd/clntxdr.c')
-rw-r--r--fs/lockd/clntxdr.c621
1 files changed, 621 insertions, 0 deletions
diff --git a/fs/lockd/clntxdr.c b/fs/lockd/clntxdr.c
new file mode 100644
index 000000000..3e9f7874b
--- /dev/null
+++ b/fs/lockd/clntxdr.c
@@ -0,0 +1,621 @@
+/*
+ * 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>
+
+#include <uapi/linux/nfs2.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;
+
+ *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;
+
+ 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)
+{
+ 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)
+{
+ 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;
+
+ WARN_ON_ONCE(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(ntohl(*p) > ntohl(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;
+
+ 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 const struct rpc_version nlm_version1 = {
+ .number = 1,
+ .nrprocs = ARRAY_SIZE(nlm_procedures),
+ .procs = nlm_procedures,
+};
+
+static const struct rpc_version nlm_version3 = {
+ .number = 3,
+ .nrprocs = ARRAY_SIZE(nlm_procedures),
+ .procs = nlm_procedures,
+};
+
+static const 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;
+
+const struct rpc_program nlm_program = {
+ .name = "lockd",
+ .number = NLM_PROGRAM,
+ .nrvers = ARRAY_SIZE(nlm_versions),
+ .version = nlm_versions,
+ .stats = &nlm_rpc_stats,
+};