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, u32 *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
  78 #define rpc_auth_ok             __constant_htonl(RPC_AUTH_OK)
  79 #define rpc_autherr_badcred     __constant_htonl(RPC_AUTH_BADCRED)
  80 #define rpc_autherr_rejectedcred __constant_htonl(RPC_AUTH_REJECTEDCRED)
  81 #define rpc_autherr_badverf     __constant_htonl(RPC_AUTH_BADVERF)
  82 #define rpc_autherr_rejectedverf __constant_htonl(RPC_AUTH_REJECTEDVERF)
  83 #define rpc_autherr_tooweak     __constant_htonl(RPC_AUTH_TOOWEAK)
  84 #define rpcsec_gsserr_credproblem       __constant_htonl(RPCSEC_GSS_CREDPROBLEM)
  85 #define rpcsec_gsserr_ctxproblem        __constant_htonl(RPCSEC_GSS_CTXPROBLEM)
  86 #define rpc_autherr_oldseqnum   __constant_htonl(101)
  87
  88 /*
  89  * Miscellaneous XDR helper functions
  90  */
  91 u32 *   xdr_encode_opaque_fixed(u32 *p, const void *ptr, unsigned int len);
  92 u32 *   xdr_encode_opaque(u32 *p, const void *ptr, unsigned int len);
  93 u32 *   xdr_encode_string(u32 *p, const char *s);
  94 u32 *   xdr_decode_string_inplace(u32 *p, char **sp, int *lenp, int maxlen);
  95 u32 *   xdr_encode_netobj(u32 *p, const struct xdr_netobj *);
  96 u32 *   xdr_decode_netobj(u32 *p, struct xdr_netobj *);
  97
  98 void    xdr_encode_pages(struct xdr_buf *, struct page **, unsigned int,
  99                          unsigned int);
 100 void    xdr_inline_pages(struct xdr_buf *, unsigned int,
 101                          struct page **, unsigned int, unsigned int);
 102
 103 static inline u32 *xdr_encode_array(u32 *p, const void *s, unsigned int len)
 104 {
 105         return xdr_encode_opaque(p, s, len);
 106 }
 107
 108 /*
 109  * Decode 64bit quantities (NFSv3 support)
 110  */
 111 static inline u32 *
 112 xdr_encode_hyper(u32 *p, __u64 val)
 113 {
 114         *p++ = htonl(val >> 32);
 115         *p++ = htonl(val & 0xFFFFFFFF);
 116         return p;
 117 }
 118
 119 static inline u32 *
 120 xdr_decode_hyper(u32 *p, __u64 *valp)
 121 {
 122         *valp  = ((__u64) ntohl(*p++)) << 32;
 123         *valp |= ntohl(*p++);
 124         return p;
 125 }
 126
 127 /*
 128  * Adjust kvec to reflect end of xdr'ed data (RPC client XDR)
 129  */
 130 static inline int
 131 xdr_adjust_iovec(struct kvec *iov, u32 *p)
 132 {
 133         return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base);
 134 }
 135
 136 /*
 137  * XDR buffer helper functions
 138  */
 139 extern void xdr_shift_buf(struct xdr_buf *, size_t);
 140 extern void xdr_buf_from_iov(struct kvec *, struct xdr_buf *);
 141 extern int xdr_buf_subsegment(struct xdr_buf *, struct xdr_buf *, int, int);
 142 extern int xdr_buf_read_netobj(struct xdr_buf *, struct xdr_netobj *, int);
 143 extern int read_bytes_from_xdr_buf(struct xdr_buf *, int, void *, int);
 144 extern int write_bytes_to_xdr_buf(struct xdr_buf *, int, void *, int);
 145
 146 /*
 147  * Helper structure for copying from an sk_buff.
 148  */
 149 typedef struct {
 150         struct sk_buff  *skb;
 151         unsigned int    offset;
 152         size_t          count;
 153         unsigned int    csum;
 154 } skb_reader_t;
 155
 156 typedef size_t (*skb_read_actor_t)(skb_reader_t *desc, void *to, size_t len);
 157
 158 extern int csum_partial_copy_to_xdr(struct xdr_buf *, struct sk_buff *);
 159 extern ssize_t xdr_partial_copy_from_skb(struct xdr_buf *, unsigned int,
 160                 skb_reader_t *, skb_read_actor_t);
 161
 162 extern int xdr_encode_word(struct xdr_buf *, int, u32);
 163 extern int xdr_decode_word(struct xdr_buf *, int, u32 *);
 164
 165 struct xdr_array2_desc;
 166 typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem);
 167 struct xdr_array2_desc {
 168         unsigned int elem_size;
 169         unsigned int array_len;
 170         unsigned int array_maxlen;
 171         xdr_xcode_elem_t xcode;
 172 };
 173
 174 extern int xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
 175                              struct xdr_array2_desc *desc);
 176 extern int xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
 177                              struct xdr_array2_desc *desc);
 178
 179 /*
 180  * Provide some simple tools for XDR buffer overflow-checking etc.
 181  */
 182 struct xdr_stream {
 183         uint32_t *p;            /* start of available buffer */
 184         struct xdr_buf *buf;    /* XDR buffer to read/write */
 185
 186         uint32_t *end;          /* end of available buffer space */
 187         struct kvec *iov;       /* pointer to the current kvec */
 188 };
 189
 190 extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, uint32_t *p);
 191 extern uint32_t *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes);
 192 extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages,
 193                 unsigned int base, unsigned int len);
 194 extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, uint32_t *p);
 195 extern uint32_t *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
 196 extern void xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
 197 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
 198
 199 #endif /* __KERNEL__ */
 200
 201 #endif /* _SUNRPC_XDR_H_ */