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 #include <linux/scatterlist.h>
  15 #include <linux/smp_lock.h>
  16
  17 /*
  18  * Buffer adjustment
  19  */
  20 #define XDR_QUADLEN(l)          (((l) + 3) >> 2)
  21
  22 /*
  23  * Generic opaque `network object.' At the kernel level, this type
  24  * is used only by lockd.
  25  */
  26 #define XDR_MAX_NETOBJ          1024
  27 struct xdr_netobj {
  28         unsigned int            len;
  29         u8 *                    data;
  30 };
  31
  32 /*
  33  * This is the generic XDR function. rqstp is either a rpc_rqst (client
  34  * side) or svc_rqst pointer (server side).
  35  * Encode functions always assume there's enough room in the buffer.
  36  */
  37 typedef int     (*kxdrproc_t)(void *rqstp, __be32 *data, void *obj);
  38
  39 /*
  40  * We're still requiring the BKL in the xdr code until it's been
  41  * more carefully audited, at which point this wrapper will become
  42  * unnecessary.
  43  */
  44 static inline int rpc_call_xdrproc(kxdrproc_t xdrproc, void *rqstp, __be32 *data, void *obj)
  45 {
  46         int ret;
  47
  48         lock_kernel();
  49         ret = xdrproc(rqstp, data, obj);
  50         unlock_kernel();
  51         return ret;
  52 }
  53
  54 /*
  55  * Basic structure for transmission/reception of a client XDR message.
  56  * Features a header (for a linear buffer containing RPC headers
  57  * and the data payload for short messages), and then an array of
  58  * pages.
  59  * The tail iovec allows you to append data after the page array. Its
  60  * main interest is for appending padding to the pages in order to
  61  * satisfy the int_32-alignment requirements in RFC1832.
  62  *
  63  * For the future, we might want to string several of these together
  64  * in a list if anybody wants to make use of NFSv4 COMPOUND
  65  * operations and/or has a need for scatter/gather involving pages.
  66  */
  67 struct xdr_buf {
  68         struct kvec     head[1],        /* RPC header + non-page data */
  69                         tail[1];        /* Appended after page data */
  70
  71         struct page **  pages;          /* Array of contiguous pages */
  72         unsigned int    page_base,      /* Start of page data */
  73                         page_len,       /* Length of page data */
  74                         flags;          /* Flags for data disposition */
  75 #define XDRBUF_READ             0x01            /* target of file read */
  76 #define XDRBUF_WRITE            0x02            /* source of file write */
  77
  78         unsigned int    buflen,         /* Total length of storage buffer */
  79                         len;            /* Length of XDR encoded message */
  80
  81 };
  82
  83 /*
  84  * pre-xdr'ed macros.
  85  */
  86
  87 #define xdr_zero        __constant_htonl(0)
  88 #define xdr_one         __constant_htonl(1)
  89 #define xdr_two         __constant_htonl(2)
  90
  91 #define rpc_success             __constant_htonl(RPC_SUCCESS)
  92 #define rpc_prog_unavail        __constant_htonl(RPC_PROG_UNAVAIL)
  93 #define rpc_prog_mismatch       __constant_htonl(RPC_PROG_MISMATCH)
  94 #define rpc_proc_unavail        __constant_htonl(RPC_PROC_UNAVAIL)
  95 #define rpc_garbage_args        __constant_htonl(RPC_GARBAGE_ARGS)
  96 #define rpc_system_err          __constant_htonl(RPC_SYSTEM_ERR)
  97 #define rpc_drop_reply          __constant_htonl(RPC_DROP_REPLY)
  98
  99 #define rpc_auth_ok             __constant_htonl(RPC_AUTH_OK)
 100 #define rpc_autherr_badcred     __constant_htonl(RPC_AUTH_BADCRED)
 101 #define rpc_autherr_rejectedcred __constant_htonl(RPC_AUTH_REJECTEDCRED)
 102 #define rpc_autherr_badverf     __constant_htonl(RPC_AUTH_BADVERF)
 103 #define rpc_autherr_rejectedverf __constant_htonl(RPC_AUTH_REJECTEDVERF)
 104 #define rpc_autherr_tooweak     __constant_htonl(RPC_AUTH_TOOWEAK)
 105 #define rpcsec_gsserr_credproblem       __constant_htonl(RPCSEC_GSS_CREDPROBLEM)
 106 #define rpcsec_gsserr_ctxproblem        __constant_htonl(RPCSEC_GSS_CTXPROBLEM)
 107 #define rpc_autherr_oldseqnum   __constant_htonl(101)
 108
 109 /*
 110  * Miscellaneous XDR helper functions
 111  */
 112 __be32 *xdr_encode_opaque_fixed(__be32 *p, const void *ptr, unsigned int len);
 113 __be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int len);
 114 __be32 *xdr_encode_string(__be32 *p, const char *s);
 115 __be32 *xdr_decode_string_inplace(__be32 *p, char **sp, unsigned int *lenp,
 116                         unsigned int maxlen);
 117 __be32 *xdr_encode_netobj(__be32 *p, const struct xdr_netobj *);
 118 __be32 *xdr_decode_netobj(__be32 *p, struct xdr_netobj *);
 119
 120 void    xdr_encode_pages(struct xdr_buf *, struct page **, unsigned int,
 121                          unsigned int);
 122 void    xdr_inline_pages(struct xdr_buf *, unsigned int,
 123                          struct page **, unsigned int, unsigned int);
 124
 125 static inline __be32 *xdr_encode_array(__be32 *p, const void *s, unsigned int len)
 126 {
 127         return xdr_encode_opaque(p, s, len);
 128 }
 129
 130 /*
 131  * Decode 64bit quantities (NFSv3 support)
 132  */
 133 static inline __be32 *
 134 xdr_encode_hyper(__be32 *p, __u64 val)
 135 {
 136         *p++ = htonl(val >> 32);
 137         *p++ = htonl(val & 0xFFFFFFFF);
 138         return p;
 139 }
 140
 141 static inline __be32 *
 142 xdr_decode_hyper(__be32 *p, __u64 *valp)
 143 {
 144         *valp  = ((__u64) ntohl(*p++)) << 32;
 145         *valp |= ntohl(*p++);
 146         return p;
 147 }
 148
 149 /*
 150  * Adjust kvec to reflect end of xdr'ed data (RPC client XDR)
 151  */
 152 static inline int
 153 xdr_adjust_iovec(struct kvec *iov, __be32 *p)
 154 {
 155         return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base);
 156 }
 157
 158 /*
 159  * XDR buffer helper functions
 160  */
 161 extern void xdr_shift_buf(struct xdr_buf *, size_t);
 162 extern void xdr_buf_from_iov(struct kvec *, struct xdr_buf *);
 163 extern int xdr_buf_subsegment(struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int);
 164 extern int xdr_buf_read_netobj(struct xdr_buf *, struct xdr_netobj *, unsigned int);
 165 extern int read_bytes_from_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
 166 extern int write_bytes_to_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
 167
 168 /*
 169  * Helper structure for copying from an sk_buff.
 170  */
 171 struct xdr_skb_reader {
 172         struct sk_buff  *skb;
 173         unsigned int    offset;
 174         size_t          count;
 175         __wsum          csum;
 176 };
 177
 178 typedef size_t (*xdr_skb_read_actor)(struct xdr_skb_reader *desc, void *to, size_t len);
 179
 180 size_t xdr_skb_read_bits(struct xdr_skb_reader *desc, void *to, size_t len);
 181 extern int csum_partial_copy_to_xdr(struct xdr_buf *, struct sk_buff *);
 182 extern ssize_t xdr_partial_copy_from_skb(struct xdr_buf *, unsigned int,
 183                 struct xdr_skb_reader *, xdr_skb_read_actor);
 184
 185 extern int xdr_encode_word(struct xdr_buf *, unsigned int, u32);
 186 extern int xdr_decode_word(struct xdr_buf *, unsigned int, u32 *);
 187
 188 struct xdr_array2_desc;
 189 typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem);
 190 struct xdr_array2_desc {
 191         unsigned int elem_size;
 192         unsigned int array_len;
 193         unsigned int array_maxlen;
 194         xdr_xcode_elem_t xcode;
 195 };
 196
 197 extern int xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
 198                              struct xdr_array2_desc *desc);
 199 extern int xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
 200                              struct xdr_array2_desc *desc);
 201
 202 /*
 203  * Provide some simple tools for XDR buffer overflow-checking etc.
 204  */
 205 struct xdr_stream {
 206         __be32 *p;              /* start of available buffer */
 207         struct xdr_buf *buf;    /* XDR buffer to read/write */
 208
 209         __be32 *end;            /* end of available buffer space */
 210         struct kvec *iov;       /* pointer to the current kvec */
 211 };
 212
 213 extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
 214 extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes);
 215 extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages,
 216                 unsigned int base, unsigned int len);
 217 extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
 218 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
 219 extern void xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
 220 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
 221 extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);
 222
 223 #endif /* __KERNEL__ */
 224
 225 #endif /* _SUNRPC_XDR_H_ */