/* SPDX-License-Identifier: GPL-2.0 */
/*
* XDR standard data types and function declarations
*
* Copyright (C) 1995-1997 Olaf Kirch <[email protected]>
*
* Based on:
* RFC 4506 "XDR: External Data Representation Standard", May 2006
*/
#ifndef _SUNRPC_XDR_H_
#define _SUNRPC_XDR_H_
#include <linux/uio.h>
#include <asm/byteorder.h>
#include <linux/unaligned.h>
#include <linux/scatterlist.h>
struct bio_vec;
struct rpc_rqst;
/*
* Size of an XDR encoding unit in bytes, i.e. 32 bits,
* as defined in Section 3 of RFC 4506. All encoded
* XDR data items are aligned on a boundary of 32 bits.
*/
#define XDR_UNIT sizeof(__be32)
/*
* Buffer adjustment
*/
#define XDR_QUADLEN(l) (((l) + 3) >> 2)
/*
* Generic opaque `network object.'
*/
#define XDR_MAX_NETOBJ 1024
struct xdr_netobj {
unsigned int len;
u8 * data;
};
/*
* Basic structure for transmission/reception of a client XDR message.
* Features a header (for a linear buffer containing RPC headers
* and the data payload for short messages), and then an array of
* pages.
* The tail iovec allows you to append data after the page array. Its
* main interest is for appending padding to the pages in order to
* satisfy the int_32-alignment requirements in RFC1832.
*
* For the future, we might want to string several of these together
* in a list if anybody wants to make use of NFSv4 COMPOUND
* operations and/or has a need for scatter/gather involving pages.
*/
struct xdr_buf {
struct kvec head[1], /* RPC header + non-page data */
tail[1]; /* Appended after page data */
struct bio_vec *bvec;
struct page ** pages; /* Array of pages */
unsigned int page_base, /* Start of page data */
page_len, /* Length of page data */
flags; /* Flags for data disposition */
#define XDRBUF_READ 0x01 /* target of file read */
#define XDRBUF_WRITE 0x02 /* source of file write */
#define XDRBUF_SPARSE_PAGES 0x04 /* Page array is sparse */
unsigned int buflen, /* Total length of storage buffer */
len; /* Length of XDR encoded message */
};
static inline void
xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
{
buf->head[0].iov_base = start;
buf->head[0].iov_len = len;
buf->tail[0].iov_len = 0;
buf->pages = NULL;
buf->page_len = 0;
buf->flags = 0;
buf->len = 0;
buf->buflen = len;
}
/*
* pre-xdr'ed macros.
*/
#define xdr_zero cpu_to_be32(0)
#define xdr_one cpu_to_be32(1)
#define xdr_two cpu_to_be32(2)
#define rpc_auth_null cpu_to_be32(RPC_AUTH_NULL)
#define rpc_auth_unix cpu_to_be32(RPC_AUTH_UNIX)
#define rpc_auth_short cpu_to_be32(RPC_AUTH_SHORT)
#define rpc_auth_gss cpu_to_be32(RPC_AUTH_GSS)
#define rpc_auth_tls cpu_to_be32(RPC_AUTH_TLS)
#define rpc_call cpu_to_be32(RPC_CALL)
#define rpc_reply cpu_to_be32(RPC_REPLY)
#define rpc_msg_accepted cpu_to_be32(RPC_MSG_ACCEPTED)
#define rpc_success cpu_to_be32(RPC_SUCCESS)
#define rpc_prog_unavail cpu_to_be32(RPC_PROG_UNAVAIL)
#define rpc_prog_mismatch cpu_to_be32(RPC_PROG_MISMATCH)
#define rpc_proc_unavail cpu_to_be32(RPC_PROC_UNAVAIL)
#define rpc_garbage_args cpu_to_be32(RPC_GARBAGE_ARGS)
#define rpc_system_err cpu_to_be32(RPC_SYSTEM_ERR)
#define rpc_drop_reply cpu_to_be32(RPC_DROP_REPLY)
#define rpc_mismatch cpu_to_be32(RPC_MISMATCH)
#define rpc_auth_error cpu_to_be32(RPC_AUTH_ERROR)
#define rpc_auth_ok cpu_to_be32(RPC_AUTH_OK)
#define rpc_autherr_badcred cpu_to_be32(RPC_AUTH_BADCRED)
#define rpc_autherr_rejectedcred cpu_to_be32(RPC_AUTH_REJECTEDCRED)
#define rpc_autherr_badverf cpu_to_be32(RPC_AUTH_BADVERF)
#define rpc_autherr_rejectedverf cpu_to_be32(RPC_AUTH_REJECTEDVERF)
#define rpc_autherr_tooweak cpu_to_be32(RPC_AUTH_TOOWEAK)
#define rpcsec_gsserr_credproblem cpu_to_be32(RPCSEC_GSS_CREDPROBLEM)
#define rpcsec_gsserr_ctxproblem cpu_to_be32(RPCSEC_GSS_CTXPROBLEM)
/*
* Miscellaneous XDR helper functions
*/
__be32 *xdr_encode_opaque_fixed(__be32 *p, const void *ptr, unsigned int len);
__be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int len);
__be32 *xdr_encode_string(__be32 *p, const char *s);
__be32 *xdr_decode_string_inplace(__be32 *p, char **sp, unsigned int *lenp,
unsigned int maxlen);
__be32 *xdr_encode_netobj(__be32 *p, const struct xdr_netobj *);
__be32 *xdr_decode_netobj(__be32 *p, struct xdr_netobj *);
void xdr_inline_pages(struct xdr_buf *, unsigned int,
struct page **, unsigned int, unsigned int);
void xdr_terminate_string(const struct xdr_buf *, const u32);
size_t xdr_buf_pagecount(const struct xdr_buf *buf);
int xdr_alloc_bvec(struct xdr_buf *buf, gfp_t gfp);
void xdr_free_bvec(struct xdr_buf *buf);
unsigned int xdr_buf_to_bvec(struct bio_vec *bvec, unsigned int bvec_size,
const struct xdr_buf *xdr);
static inline __be32 *xdr_encode_array(__be32 *p, const void *s, unsigned int len)
{
return xdr_encode_opaque(p, s, len);
}
/*
* Decode 64bit quantities (NFSv3 support)
*/
static inline __be32 *
xdr_encode_hyper(__be32 *p, __u64 val)
{
put_unaligned_be64(val, p);
return p + 2;
}
static inline __be32 *
xdr_decode_hyper(__be32 *p, __u64 *valp)
{
*valp = get_unaligned_be64(p);
return p + 2;
}
static inline __be32 *
xdr_decode_opaque_fixed(__be32 *p, void *ptr, unsigned int len)
{
memcpy(ptr, p, len);
return p + XDR_QUADLEN(len);
}
static inline void xdr_netobj_dup(struct xdr_netobj *dst,
struct xdr_netobj *src, gfp_t gfp_mask)
{
dst->data = kmemdup(src->data, src->len, gfp_mask);
dst->len = src->len;
}
/*
* Adjust kvec to reflect end of xdr'ed data (RPC client XDR)
*/
static inline int
xdr_adjust_iovec(struct kvec *iov, __be32 *p)
{
return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base);
}
/*
* XDR buffer helper functions
*/
extern void xdr_buf_from_iov(const struct kvec *, struct xdr_buf *);
extern int xdr_buf_subsegment(const struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int);
extern void xdr_buf_trim(struct xdr_buf *, unsigned int);
extern int read_bytes_from_xdr_buf(const struct xdr_buf *, unsigned int, void *, unsigned int);
extern int write_bytes_to_xdr_buf(const struct xdr_buf *, unsigned int, void *, unsigned int);
extern int xdr_encode_word(const struct xdr_buf *, unsigned int, u32);
extern int xdr_decode_word(const struct xdr_buf *, unsigned int, u32 *);
struct xdr_array2_desc;
typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem);
struct xdr_array2_desc {
unsigned int elem_size;
unsigned int array_len;
unsigned int array_maxlen;
xdr_xcode_elem_t xcode;
};
extern int xdr_decode_array2(const struct xdr_buf *buf, unsigned int base,
struct xdr_array2_desc *desc);
extern int xdr_encode_array2(const struct xdr_buf *buf, unsigned int base,
struct xdr_array2_desc *desc);
extern void _copy_from_pages(char *p, struct page **pages, size_t pgbase,
size_t len);
/*
* Provide some simple tools for XDR buffer overflow-checking etc.
*/
struct xdr_stream {
__be32 *p; /* start of available buffer */
struct xdr_buf *buf; /* XDR buffer to read/write */
__be32 *end; /* end of available buffer space */
struct kvec *iov; /* pointer to the current kvec */
struct kvec scratch; /* Scratch buffer */
struct page **page_ptr; /* pointer to the current page */
void *page_kaddr; /* kmapped address of the current page */
unsigned int nwords; /* Remaining decode buffer length */
struct rpc_rqst *rqst; /* For debugging */
};
/*
* These are the xdr_stream style generic XDR encode and decode functions.
*/
typedef void (*kxdreproc_t)(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
const void *obj);
typedef int (*kxdrdproc_t)(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
void *obj);
extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf,
__be32 *p, struct rpc_rqst *rqst);
extern void xdr_init_encode_pages(struct xdr_stream *xdr, struct xdr_buf *buf,
struct page **pages, struct rpc_rqst *rqst);
extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes);
extern int xdr_reserve_space_vec(struct xdr_stream *xdr, size_t nbytes);
extern void __xdr_commit_encode(struct xdr_stream *xdr);
extern void xdr_truncate_encode(struct xdr_stream *xdr, size_t len);
extern void xdr_truncate_decode(struct xdr_stream *xdr, size_t len);
extern int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen);
extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages,
unsigned int base, unsigned int len);
extern unsigned int xdr_stream_pos(const struct xdr_stream *xdr);
extern unsigned int xdr_page_pos(const struct xdr_stream *xdr);
extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf,
__be32 *p, struct rpc_rqst *rqst);
extern void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf,
struct page **pages, unsigned int len);
extern void xdr_finish_decode(struct xdr_stream *xdr);
extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
extern int xdr_process_buf(const struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);
extern void xdr_set_pagelen(struct xdr_stream *, unsigned int len);
extern bool xdr_stream_subsegment(struct xdr_stream *xdr, struct xdr_buf *subbuf,
unsigned int len);
extern unsigned int xdr_stream_move_subsegment(struct xdr_stream *xdr, unsigned int offset,
unsigned int target, unsigned int length);
extern unsigned int xdr_stream_zero(struct xdr_stream *xdr, unsigned int offset,
unsigned int length);
/**
* xdr_set_scratch_buffer - Attach a scratch buffer for decoding data.
* @xdr: pointer to xdr_stream struct
* @buf: pointer to an empty buffer
* @buflen: size of 'buf'
*
* The scratch buffer is used when decoding from an array of pages.
* If an xdr_inline_decode() call spans across page boundaries, then
* we copy the data into the scratch buffer in order to allow linear
* access.
*/
static inline void
xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen)
{
xdr->scratch.iov_base = buf;
xdr->scratch.iov_len = buflen;
}
/**
* xdr_set_scratch_page - Attach a scratch buffer for decoding data
* @xdr: pointer to xdr_stream struct
* @page: an anonymous page
*
* See xdr_set_scratch_buffer().
*/
static inline void
xdr_set_scratch_page(struct xdr_stream *xdr, struct page *page)
{
xdr_set_scratch_buffer(xdr, page_address(page), PAGE_SIZE);
}
/**
* xdr_reset_scratch_buffer - Clear scratch buffer information
* @xdr: pointer to xdr_stream struct
*
* See xdr_set_scratch_buffer().
*/
static inline void
xdr_reset_scratch_buffer(struct xdr_stream *xdr)
{
xdr_set_scratch_buffer(xdr, NULL, 0);
}
/**
* xdr_commit_encode - Ensure all data is written to xdr->buf
* @xdr: pointer to xdr_stream
*
* Handle encoding across page boundaries by giving the caller a
* temporary location to write to, then later copying the data into
* place. __xdr_commit_encode() does that copying.
*/
static inline void xdr_commit_encode(struct xdr_stream *xdr)
{
if (unlikely(xdr->scratch.iov_len))
__xdr_commit_encode(xdr);
}
/**
* xdr_stream_remaining - Return the number of bytes remaining in the stream
* @xdr: pointer to struct xdr_stream
*
* Return value:
* Number of bytes remaining in @xdr before xdr->end
*/
static inline size_t
xdr_stream_remaining(const struct xdr_stream *xdr)
{
return xdr->nwords << 2;
}
ssize_t xdr_stream_decode_opaque(struct xdr_stream *xdr, void *ptr,
size_t size);
ssize_t xdr_stream_decode_opaque_dup(struct xdr_stream *xdr, void **ptr,
size_t maxlen, gfp_t gfp_flags);
ssize_t xdr_stream_decode_string(struct xdr_stream *xdr, char *str,
size_t size);
ssize_t xdr_stream_decode_string_dup(struct xdr_stream *xdr, char **str,
size_t maxlen, gfp_t gfp_flags);
ssize_t xdr_stream_decode_opaque_auth(struct xdr_stream *xdr, u32 *flavor,
void **body, unsigned int *body_len);
ssize_t xdr_stream_encode_opaque_auth(struct xdr_stream *xdr, u32 flavor,
void *body, unsigned int body_len);
/**
* xdr_align_size - Calculate padded size of an object
* @n: Size of an object being XDR encoded (in bytes)
*
* Return value:
* Size (in bytes) of the object including xdr padding
*/
static inline size_t
xdr_align_size(size_t n)
{
const size_t mask = XDR_UNIT - 1;
return (n + mask) & ~mask;
}
/**
* xdr_pad_size - Calculate size of an object's pad
* @n: Size of an object being XDR encoded (in bytes)
*
* This implementation avoids the need for conditional
* branches or modulo division.
*
* Return value:
* Size (in bytes) of the needed XDR pad
*/
static inline size_t xdr_pad_size(size_t n)
{
return xdr_align_size(n) - n;
}
/**
* xdr_stream_encode_item_present - Encode a "present" list item
* @xdr: pointer to xdr_stream
*
* Return values:
* On success, returns length in bytes of XDR buffer consumed
* %-EMSGSIZE on XDR buffer overflow
*/
static inline ssize_t xdr_stream_encode_item_present(struct xdr_stream *xdr)
{
const size_t len = XDR_UNIT;
__be32 *p = xdr_reserve_space(xdr, len);
if (unlikely(!p))
return -EMSGSIZE;
*p = xdr_one;
return len;
}
/**
* xdr_stream_encode_item_absent - Encode a "not present" list item
* @xdr: pointer to xdr_stream
*
* Return values:
* On success, returns length in bytes of XDR buffer consumed
* %-EMSGSIZE on XDR buffer overflow
*/
static inline int xdr_stream_encode_item_absent(struct xdr_stream *xdr)
{
const size_t len = XDR_UNIT;
__be32 *p = xdr_reserve_space(xdr, len);
if (unlikely(!p))
return -EMSGSIZE;
*p = xdr_zero;
return len;
}
/**
* xdr_encode_bool - Encode a boolean item
* @p: address in a buffer into which to encode
* @n: boolean value to encode
*
* Return value:
* Address of item following the encoded boolean
*/
static inline __be32 *xdr_encode_bool(__be32 *p, u32 n)
{
*p++ = n ? xdr_one : xdr_zero;
return p;
}
/**
* xdr_stream_encode_bool - Encode a boolean item
* @xdr: pointer to xdr_stream
* @n: boolean value to encode
*
* Return values:
* On success, returns length in bytes of XDR buffer consumed
* %-EMSGSIZE on XDR buffer overflow
*/
static inline int xdr_stream_encode_bool(struct xdr_stream *xdr, __u32 n)
{
const size_t len = XDR_UNIT;
__be32 *p = xdr_reserve_space(xdr, len);
if (unlikely(!p))
return -EMSGSIZE;
xdr_encode_bool(p, n);
return len;
}
/**
* xdr_stream_encode_u32 - Encode a 32-bit integer
* @xdr: pointer to xdr_stream
* @n: integer to encode
*
* Return values:
* On success, returns length in bytes of XDR buffer consumed
* %-EMSGSIZE on XDR buffer overflow
*/
static inline ssize_t
xdr_stream_encode_u32(struct xdr_stream *xdr, __u32 n)
{
const size_t len = sizeof(n);
__be32 *p = xdr_reserve_space(xdr, len);
if (unlikely(!p))
return -EMSGSIZE;
*p = cpu_to_be32(n);
return len;
}
/**
* xdr_stream_encode_be32 - Encode a big-endian 32-bit integer
* @xdr: pointer to xdr_stream
* @n: integer to encode
*
* Return values:
* On success, returns length in bytes of XDR buffer consumed
* %-EMSGSIZE on XDR buffer overflow
*/
static inline ssize_t
xdr_stream_encode_be32(struct xdr_stream *xdr, __be32 n)
{
const size_t len = sizeof(n);
__be32 *p = xdr_reserve_space(xdr, len);
if (unlikely(!p))
return -EMSGSIZE;
*p = n;
return len;
}
/**
* xdr_stream_encode_u64 - Encode a 64-bit integer
* @xdr: pointer to xdr_stream
* @n: 64-bit integer to encode
*
* Return values:
* On success, returns length in bytes of XDR buffer consumed
* %-EMSGSIZE on XDR buffer overflow
*/
static inline ssize_t
xdr_stream_encode_u64(struct xdr_stream *xdr, __u64 n)
{
const size_t len = sizeof(n);
__be32 *p = xdr_reserve_space(xdr, len);
if (unlikely(!p))
return -EMSGSIZE;
xdr_encode_hyper(p, n);
return len;
}
/**
* xdr_stream_encode_opaque_inline - Encode opaque xdr data
* @xdr: pointer to xdr_stream
* @ptr: pointer to void pointer
* @len: size of object
*
* Return values:
* On success, returns length in bytes of XDR buffer consumed
* %-EMSGSIZE on XDR buffer overflow
*/
static inline ssize_t
xdr_stream_encode_opaque_inline(struct xdr_stream *xdr, void **ptr, size_t len)
{
size_t count = sizeof(__u32) + xdr_align_size(len);
__be32 *p = xdr_reserve_space(xdr, count);
if (unlikely(!p)) {
*ptr = NULL;
return -EMSGSIZE;
}
xdr_encode_opaque(p, NULL, len);
*ptr = ++p;
return count;
}
/**
* xdr_stream_encode_opaque_fixed - Encode fixed length opaque xdr data
* @xdr: pointer to xdr_stream
* @ptr: pointer to opaque data object
* @len: size of object pointed to by @ptr
*
* Return values:
* On success, returns length in bytes of XDR buffer consumed
* %-EMSGSIZE on XDR buffer overflow
*/
static inline ssize_t
xdr_stream_encode_opaque_fixed(struct xdr_stream *xdr, const void *ptr, size_t len)
{
__be32 *p = xdr_reserve_space(xdr, len);
if (unlikely(!p))
return -EMSGSIZE;
xdr_encode_opaque_fixed(p, ptr, len);
return xdr_align_size(len);
}
/**
* xdr_stream_encode_opaque - Encode variable length opaque xdr data
* @xdr: pointer to xdr_stream
* @ptr: pointer to opaque data object
* @len: size of object pointed to by @ptr
*
* Return values:
* On success, returns length in bytes of XDR buffer consumed
* %-EMSGSIZE on XDR buffer overflow
*/
static inline ssize_t
xdr_stream_encode_opaque(struct xdr_stream *xdr, const void *ptr, size_t len)
{
size_t count = sizeof(__u32) + xdr_align_size(len);
__be32 *p = xdr_reserve_space(xdr, count);
if (unlikely(!p))
return -EMSGSIZE;
xdr_encode_opaque(p, ptr, len);
return count;
}
/**
* xdr_stream_encode_uint32_array - Encode variable length array of integers
* @xdr: pointer to xdr_stream
* @array: array of integers
* @array_size: number of elements in @array
*
* Return values:
* On success, returns length in bytes of XDR buffer consumed
* %-EMSGSIZE on XDR buffer overflow
*/
static inline ssize_t
xdr_stream_encode_uint32_array(struct xdr_stream *xdr,
const __u32 *array, size_t array_size)
{
ssize_t ret = (array_size+1) * sizeof(__u32);
__be32 *p = xdr_reserve_space(xdr, ret);
if (unlikely(!p))
return -EMSGSIZE;
*p++ = cpu_to_be32(array_size);
for (; array_size > 0; p++, array++, array_size--)
*p = cpu_to_be32p(array);
return ret;
}
/**
* xdr_item_is_absent - symbolically handle XDR discriminators
* @p: pointer to undecoded discriminator
*
* Return values:
* %true if the following XDR item is absent
* %false if the following XDR item is present
*/
static inline bool xdr_item_is_absent(const __be32 *p)
{
return *p == xdr_zero;
}
/**
* xdr_item_is_present - symbolically handle XDR discriminators
* @p: pointer to undecoded discriminator
*
* Return values:
* %true if the following XDR item is present
* %false if the following XDR item is absent
*/
static inline bool xdr_item_is_present(const __be32 *p)
{
return *p != xdr_zero;
}
/**
* xdr_stream_decode_bool - Decode a boolean
* @xdr: pointer to xdr_stream
* @ptr: pointer to a u32 in which to store the result
*
* Return values:
* %0 on success
* %-EBADMSG on XDR buffer overflow
*/
static inline ssize_t
xdr_stream_decode_bool(struct xdr_stream *xdr, __u32 *ptr)
{
const size_t count = sizeof(*ptr);
__be32 *p = xdr_inline_decode(xdr, count);
if (unlikely(!p))
return -EBADMSG;
*ptr = (*p != xdr_zero);
return 0;
}
/**
* xdr_stream_decode_u32 - Decode a 32-bit integer
* @xdr: pointer to xdr_stream
* @ptr: location to store integer
*
* Return values:
* %0 on success
* %-EBADMSG on XDR buffer overflow
*/
static inline ssize_t
xdr_stream_decode_u32(struct xdr_stream *xdr, __u32 *ptr)
{
const size_t count = sizeof(*ptr);
__be32 *p = xdr_inline_decode(xdr, count);
if (unlikely(!p))
return -EBADMSG;
*ptr = be32_to_cpup(p);
return 0;
}
/**
* xdr_stream_decode_u64 - Decode a 64-bit integer
* @xdr: pointer to xdr_stream
* @ptr: location to store 64-bit integer
*
* Return values:
* %0 on success
* %-EBADMSG on XDR buffer overflow
*/
static inline ssize_t
xdr_stream_decode_u64(struct xdr_stream *xdr, __u64 *ptr)
{
const size_t count = sizeof(*ptr);
__be32 *p = xdr_inline_decode(xdr, count);
if (unlikely(!p))
return -EBADMSG;
xdr_decode_hyper(p, ptr);
return 0;
}
/**
* xdr_stream_decode_opaque_fixed - Decode fixed length opaque xdr data
* @xdr: pointer to xdr_stream
* @ptr: location to store data
* @len: size of buffer pointed to by @ptr
*
* Return values:
* On success, returns size of object stored in @ptr
* %-EBADMSG on XDR buffer overflow
*/
static inline ssize_t
xdr_stream_decode_opaque_fixed(struct xdr_stream *xdr, void *ptr, size_t len)
{
__be32 *p = xdr_inline_decode(xdr, len);
if (unlikely(!p))
return -EBADMSG;
xdr_decode_opaque_fixed(p, ptr, len);
return len;
}
/**
* xdr_stream_decode_opaque_inline - Decode variable length opaque xdr data
* @xdr: pointer to xdr_stream
* @ptr: location to store pointer to opaque data
* @maxlen: maximum acceptable object size
*
* Note: the pointer stored in @ptr cannot be assumed valid after the XDR
* buffer has been destroyed, or even after calling xdr_inline_decode()
* on @xdr. It is therefore expected that the object it points to should
* be processed immediately.
*
* Return values:
* On success, returns size of object stored in *@ptr
* %-EBADMSG on XDR buffer overflow
* %-EMSGSIZE if the size of the object would exceed @maxlen
*/
static inline ssize_t
xdr_stream_decode_opaque_inline(struct xdr_stream *xdr, void **ptr, size_t maxlen)
{
__be32 *p;
__u32 len;
*ptr = NULL;
if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0))
return -EBADMSG;
if (len != 0) {
p = xdr_inline_decode(xdr, len);
if (unlikely(!p))
return -EBADMSG;
if (unlikely(len > maxlen))
return -EMSGSIZE;
*ptr = p;
}
return len;
}
/**
* xdr_stream_decode_uint32_array - Decode variable length array of integers
* @xdr: pointer to xdr_stream
* @array: location to store the integer array or NULL
* @array_size: number of elements to store
*
* Return values:
* On success, returns number of elements stored in @array
* %-EBADMSG on XDR buffer overflow
* %-EMSGSIZE if the size of the array exceeds @array_size
*/
static inline ssize_t
xdr_stream_decode_uint32_array(struct xdr_stream *xdr,
__u32 *array, size_t array_size)
{
__be32 *p;
__u32 len;
ssize_t retval;
if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0))
return -EBADMSG;
if (U32_MAX >= SIZE_MAX / sizeof(*p) && len > SIZE_MAX / sizeof(*p))
return -EBADMSG;
p = xdr_inline_decode(xdr, len * sizeof(*p));
if (unlikely(!p))
return -EBADMSG;
if (array == NULL)
return len;
if (len <= array_size) {
if (len < array_size)
memset(array+len, 0, (array_size-len)*sizeof(*array));
array_size = len;
retval = len;
} else
retval = -EMSGSIZE;
for (; array_size > 0; p++, array++, array_size--)
*array = be32_to_cpup(p);
return retval;
}
#endif /* _SUNRPC_XDR_H_ */
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