include/linux/sunrpc/xdr.h

   1 /*
   2  * include/linux/sunrpc/xdr.h
   3  *
   4  * Copyright (C) 1995-1997 Olaf Kirch <okir@monad.swb.de>
   5  */
   6
   7 #ifndef _SUNRPC_XDR_H_
   8 #define _SUNRPC_XDR_H_
   9
  10 #ifdef __KERNEL__
  11
  12 #include <linux/uio.h>
  13 #include <asm/byteorder.h>
  14
  15 /*
  16  * Buffer adjustment
  17  */
  18 #define XDR_QUADLEN(l)          (((l) + 3) >> 2)
  19
  20 /*
  21  * Generic opaque `network object.' At the kernel level, this type
  22  * is used only by lockd.
  23  */
  24 #define XDR_MAX_NETOBJ          1024
  25 struct xdr_netobj {
  26         unsigned int            len;
  27         u8 *                    data;
  28 };
  29
  30 /*
  31  * This is the generic XDR function. rqstp is either a rpc_rqst (client
  32  * side) or svc_rqst pointer (server side).
  33  * Encode functions always assume there's enough room in the buffer.
  34  */
  35 typedef int     (*kxdrproc_t)(void *rqstp, __be32 *data, void *obj);
  36
  37 /*
  38  * Basic structure for transmission/reception of a client XDR message.
  39  * Features a header (for a linear buffer containing RPC headers
  40  * and the data payload for short messages), and then an array of
  41  * pages.
  42  * The tail iovec allows you to append data after the page array. Its
  43  * main interest is for appending padding to the pages in order to
  44  * satisfy the int_32-alignment requirements in RFC1832.
  45  *
  46  * For the future, we might want to string several of these together
  47  * in a list if anybody wants to make use of NFSv4 COMPOUND
  48  * operations and/or has a need for scatter/gather involving pages.
  49  */
  50 struct xdr_buf {
  51         struct kvec     head[1],        /* RPC header + non-page data */
  52                         tail[1];        /* Appended after page data */
  53
  54         struct page **  pages;          /* Array of contiguous pages */
  55         unsigned int    page_base,      /* Start of page data */
  56                         page_len;       /* Length of page data */
  57
  58         unsigned int    buflen,         /* Total length of storage buffer */
  59                         len;            /* Length of XDR encoded message */
  60
  61 };
  62
  63 /*
  64  * pre-xdr'ed macros.
  65  */
  66
  67 #define xdr_zero        __constant_htonl(0)
  68 #define xdr_one         __constant_htonl(1)
  69 #define xdr_two         __constant_htonl(2)
  70
  71 #define rpc_success             __constant_htonl(RPC_SUCCESS)
  72 #define rpc_prog_unavail        __constant_htonl(RPC_PROG_UNAVAIL)
  73 #define rpc_prog_mismatch       __constant_htonl(RPC_PROG_MISMATCH)
  74 #define rpc_proc_unavail        __constant_htonl(RPC_PROC_UNAVAIL)
  75 #define rpc_garbage_args        __constant_htonl(RPC_GARBAGE_ARGS)
  76 #define rpc_system_err          __constant_htonl(RPC_SYSTEM_ERR)
  77 #define rpc_drop_reply          __constant_htonl(RPC_DROP_REPLY)
  78
  79 #define rpc_auth_ok             __constant_htonl(RPC_AUTH_OK)
  80 #define rpc_autherr_badcred     __constant_htonl(RPC_AUTH_BADCRED)
  81 #define rpc_autherr_rejectedcred __constant_htonl(RPC_AUTH_REJECTEDCRED)
  82 #define rpc_autherr_badverf     __constant_htonl(RPC_AUTH_BADVERF)
  83 #define rpc_autherr_rejectedverf __constant_htonl(RPC_AUTH_REJECTEDVERF)
  84 #define rpc_autherr_tooweak     __constant_htonl(RPC_AUTH_TOOWEAK)
  85 #define rpcsec_gsserr_credproblem       __constant_htonl(RPCSEC_GSS_CREDPROBLEM)
  86 #define rpcsec_gsserr_ctxproblem        __constant_htonl(RPCSEC_GSS_CTXPROBLEM)
  87 #define rpc_autherr_oldseqnum   __constant_htonl(101)
  88
  89 /*
  90  * Miscellaneous XDR helper functions
  91  */
  92 __be32 *xdr_encode_opaque_fixed(__be32 *p, const void *ptr, unsigned int len);
  93 __be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int len);
  94 __be32 *xdr_encode_string(__be32 *p, const char *s);
  95 __be32 *xdr_decode_string_inplace(__be32 *p, char **sp, int *lenp, int maxlen);
  96 __be32 *xdr_encode_netobj(__be32 *p, const struct xdr_netobj *);
  97 __be32 *xdr_decode_netobj(__be32 *p, struct xdr_netobj *);
  98
  99 void    xdr_encode_pages(struct xdr_buf *, struct page **, unsigned int,
 100                          unsigned int);
 101 void    xdr_inline_pages(struct xdr_buf *, unsigned int,
 102                          struct page **, unsigned int, unsigned int);
 103
 104 static inline __be32 *xdr_encode_array(__be32 *p, const void *s, unsigned int len)
 105 {
 106         return xdr_encode_opaque(p, s, len);
 107 }
 108
 109 /*
 110  * Decode 64bit quantities (NFSv3 support)
 111  */
 112 static inline __be32 *
 113 xdr_encode_hyper(__be32 *p, __u64 val)
 114 {
 115         *p++ = htonl(val >> 32);
 116         *p++ = htonl(val & 0xFFFFFFFF);
 117         return p;
 118 }
 119
 120 static inline __be32 *
 121 xdr_decode_hyper(__be32 *p, __u64 *valp)
 122 {
 123         *valp  = ((__u64) ntohl(*p++)) << 32;
 124         *valp |= ntohl(*p++);
 125         return p;
 126 }
 127
 128 /*
 129  * Adjust kvec to reflect end of xdr'ed data (RPC client XDR)
 130  */
 131 static inline int
 132 xdr_adjust_iovec(struct kvec *iov, __be32 *p)
 133 {
 134         return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base);
 135 }
 136
 137 /*
 138  * XDR buffer helper functions
 139  */
 140 extern void xdr_shift_buf(struct xdr_buf *, size_t);
 141 extern void xdr_buf_from_iov(struct kvec *, struct xdr_buf *);
 142 extern int xdr_buf_subsegment(struct xdr_buf *, struct xdr_buf *, int, int);
 143 extern int xdr_buf_read_netobj(struct xdr_buf *, struct xdr_netobj *, int);
 144 extern int read_bytes_from_xdr_buf(struct xdr_buf *, int, void *, int);
 145 extern int write_bytes_to_xdr_buf(struct xdr_buf *, int, void *, int);
 146
 147 /*
 148  * Helper structure for copying from an sk_buff.
 149  */
 150 typedef struct {
 151         struct sk_buff  *skb;
 152         unsigned int    offset;
 153         size_t          count;
 154         unsigned int    csum;
 155 } skb_reader_t;
 156
 157 typedef size_t (*skb_read_actor_t)(skb_reader_t *desc, void *to, size_t len);
 158
 159 extern int csum_partial_copy_to_xdr(struct xdr_buf *, struct sk_buff *);
 160 extern ssize_t xdr_partial_copy_from_skb(struct xdr_buf *, unsigned int,
 161                 skb_reader_t *, skb_read_actor_t);
 162
 163 extern int xdr_encode_word(struct xdr_buf *, int, u32);
 164 extern int xdr_decode_word(struct xdr_buf *, int, u32 *);
 165
 166 struct xdr_array2_desc;
 167 typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem);
 168 struct xdr_array2_desc {
 169         unsigned int elem_size;
 170         unsigned int array_len;
 171         unsigned int array_maxlen;
 172         xdr_xcode_elem_t xcode;
 173 };
 174
 175 extern int xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
 176                              struct xdr_array2_desc *desc);
 177 extern int xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
 178                              struct xdr_array2_desc *desc);
 179
 180 /*
 181  * Provide some simple tools for XDR buffer overflow-checking etc.
 182  */
 183 struct xdr_stream {
 184         __be32 *p;              /* start of available buffer */
 185         struct xdr_buf *buf;    /* XDR buffer to read/write */
 186
 187         __be32 *end;            /* end of available buffer space */
 188         struct kvec *iov;       /* pointer to the current kvec */
 189 };
 190
 191 extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
 192 extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes);
 193 extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages,
 194                 unsigned int base, unsigned int len);
 195 extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
 196 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
 197 extern void xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
 198 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
 199
 200 #endif /* __KERNEL__ */
 201
 202 #endif /* _SUNRPC_XDR_H_ */