1 /*
2 * XDR standard data types and function declarations
3 *
4 * Copyright (C) 1995-1997 Olaf Kirch <okir@monad.swb.de>
5 *
6 * Based on:
7 * RFC 4506 "XDR: External Data Representation Standard", May 2006
8 */
9
10 #ifndef _SUNRPC_XDR_H_
11 #define _SUNRPC_XDR_H_
12
13 #ifdef __KERNEL__
14
15 #include <linux/uio.h>
16 #include <asm/byteorder.h>
17 #include <asm/unaligned.h>
18 #include <linux/scatterlist.h>
19
20 /*
21 * Buffer adjustment
22 */
23 #define XDR_QUADLEN(l) (((l) + 3) >> 2)
24
25 /*
26 * Generic opaque `network object.' At the kernel level, this type
27 * is used only by lockd.
28 */
29 #define XDR_MAX_NETOBJ 1024
30 struct xdr_netobj {
31 unsigned int len;
32 u8 * data;
33 };
34
35 /*
36 * This is the legacy generic XDR function. rqstp is either a rpc_rqst
37 * (client side) or svc_rqst pointer (server side).
38 * Encode functions always assume there's enough room in the buffer.
39 */
40 typedef int (*kxdrproc_t)(void *rqstp, __be32 *data, void *obj);
41
42 /*
43 * Basic structure for transmission/reception of a client XDR message.
44 * Features a header (for a linear buffer containing RPC headers
45 * and the data payload for short messages), and then an array of
46 * pages.
47 * The tail iovec allows you to append data after the page array. Its
48 * main interest is for appending padding to the pages in order to
49 * satisfy the int_32-alignment requirements in RFC1832.
50 *
51 * For the future, we might want to string several of these together
52 * in a list if anybody wants to make use of NFSv4 COMPOUND
53 * operations and/or has a need for scatter/gather involving pages.
54 */
55 struct xdr_buf {
56 struct kvec head[1], /* RPC header + non-page data */
57 tail[1]; /* Appended after page data */
58
59 struct page ** pages; /* Array of contiguous pages */
60 unsigned int page_base, /* Start of page data */
61 page_len, /* Length of page data */
62 flags; /* Flags for data disposition */
63 #define XDRBUF_READ 0x01 /* target of file read */
64 #define XDRBUF_WRITE 0x02 /* source of file write */
65
66 unsigned int buflen, /* Total length of storage buffer */
67 len; /* Length of XDR encoded message */
68 };
69
70 /*
71 * pre-xdr'ed macros.
72 */
73
74 #define xdr_zero cpu_to_be32(0)
75 #define xdr_one cpu_to_be32(1)
76 #define xdr_two cpu_to_be32(2)
77
78 #define rpc_success cpu_to_be32(RPC_SUCCESS)
79 #define rpc_prog_unavail cpu_to_be32(RPC_PROG_UNAVAIL)
80 #define rpc_prog_mismatch cpu_to_be32(RPC_PROG_MISMATCH)
81 #define rpc_proc_unavail cpu_to_be32(RPC_PROC_UNAVAIL)
82 #define rpc_garbage_args cpu_to_be32(RPC_GARBAGE_ARGS)
83 #define rpc_system_err cpu_to_be32(RPC_SYSTEM_ERR)
84 #define rpc_drop_reply cpu_to_be32(RPC_DROP_REPLY)
85
86 #define rpc_auth_ok cpu_to_be32(RPC_AUTH_OK)
87 #define rpc_autherr_badcred cpu_to_be32(RPC_AUTH_BADCRED)
88 #define rpc_autherr_rejectedcred cpu_to_be32(RPC_AUTH_REJECTEDCRED)
89 #define rpc_autherr_badverf cpu_to_be32(RPC_AUTH_BADVERF)
90 #define rpc_autherr_rejectedverf cpu_to_be32(RPC_AUTH_REJECTEDVERF)
91 #define rpc_autherr_tooweak cpu_to_be32(RPC_AUTH_TOOWEAK)
92 #define rpcsec_gsserr_credproblem cpu_to_be32(RPCSEC_GSS_CREDPROBLEM)
93 #define rpcsec_gsserr_ctxproblem cpu_to_be32(RPCSEC_GSS_CTXPROBLEM)
94 #define rpc_autherr_oldseqnum cpu_to_be32(101)
95
96 /*
97 * Miscellaneous XDR helper functions
98 */
99 __be32 *xdr_encode_opaque_fixed(__be32 *p, const void *ptr, unsigned int len);
100 __be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int len);
101 __be32 *xdr_encode_string(__be32 *p, const char *s);
102 __be32 *xdr_decode_string_inplace(__be32 *p, char **sp, unsigned int *lenp,
103 unsigned int maxlen);
104 __be32 *xdr_encode_netobj(__be32 *p, const struct xdr_netobj *);
105 __be32 *xdr_decode_netobj(__be32 *p, struct xdr_netobj *);
106
107 void xdr_encode_pages(struct xdr_buf *, struct page **, unsigned int,
108 unsigned int);
109 void xdr_inline_pages(struct xdr_buf *, unsigned int,
110 struct page **, unsigned int, unsigned int);
111 void xdr_terminate_string(struct xdr_buf *, const u32);
112
xdr_encode_array(__be32 * p,const void * s,unsigned int len)113 static inline __be32 *xdr_encode_array(__be32 *p, const void *s, unsigned int len)
114 {
115 return xdr_encode_opaque(p, s, len);
116 }
117
118 /*
119 * Decode 64bit quantities (NFSv3 support)
120 */
121 static inline __be32 *
xdr_encode_hyper(__be32 * p,__u64 val)122 xdr_encode_hyper(__be32 *p, __u64 val)
123 {
124 put_unaligned_be64(val, p);
125 return p + 2;
126 }
127
128 static inline __be32 *
xdr_decode_hyper(__be32 * p,__u64 * valp)129 xdr_decode_hyper(__be32 *p, __u64 *valp)
130 {
131 *valp = get_unaligned_be64(p);
132 return p + 2;
133 }
134
135 static inline __be32 *
xdr_decode_opaque_fixed(__be32 * p,void * ptr,unsigned int len)136 xdr_decode_opaque_fixed(__be32 *p, void *ptr, unsigned int len)
137 {
138 memcpy(ptr, p, len);
139 return p + XDR_QUADLEN(len);
140 }
141
142 /*
143 * Adjust kvec to reflect end of xdr'ed data (RPC client XDR)
144 */
145 static inline int
xdr_adjust_iovec(struct kvec * iov,__be32 * p)146 xdr_adjust_iovec(struct kvec *iov, __be32 *p)
147 {
148 return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base);
149 }
150
151 /*
152 * XDR buffer helper functions
153 */
154 extern void xdr_shift_buf(struct xdr_buf *, size_t);
155 extern void xdr_buf_from_iov(struct kvec *, struct xdr_buf *);
156 extern int xdr_buf_subsegment(struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int);
157 extern int xdr_buf_read_netobj(struct xdr_buf *, struct xdr_netobj *, unsigned int);
158 extern int read_bytes_from_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
159 extern int write_bytes_to_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
160
161 /*
162 * Helper structure for copying from an sk_buff.
163 */
164 struct xdr_skb_reader {
165 struct sk_buff *skb;
166 unsigned int offset;
167 size_t count;
168 __wsum csum;
169 };
170
171 typedef size_t (*xdr_skb_read_actor)(struct xdr_skb_reader *desc, void *to, size_t len);
172
173 size_t xdr_skb_read_bits(struct xdr_skb_reader *desc, void *to, size_t len);
174 extern int csum_partial_copy_to_xdr(struct xdr_buf *, struct sk_buff *);
175 extern ssize_t xdr_partial_copy_from_skb(struct xdr_buf *, unsigned int,
176 struct xdr_skb_reader *, xdr_skb_read_actor);
177
178 extern int xdr_encode_word(struct xdr_buf *, unsigned int, u32);
179 extern int xdr_decode_word(struct xdr_buf *, unsigned int, u32 *);
180
181 struct xdr_array2_desc;
182 typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem);
183 struct xdr_array2_desc {
184 unsigned int elem_size;
185 unsigned int array_len;
186 unsigned int array_maxlen;
187 xdr_xcode_elem_t xcode;
188 };
189
190 extern int xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
191 struct xdr_array2_desc *desc);
192 extern int xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
193 struct xdr_array2_desc *desc);
194 extern void _copy_from_pages(char *p, struct page **pages, size_t pgbase,
195 size_t len);
196
197 /*
198 * Provide some simple tools for XDR buffer overflow-checking etc.
199 */
200 struct xdr_stream {
201 __be32 *p; /* start of available buffer */
202 struct xdr_buf *buf; /* XDR buffer to read/write */
203
204 __be32 *end; /* end of available buffer space */
205 struct kvec *iov; /* pointer to the current kvec */
206 struct kvec scratch; /* Scratch buffer */
207 struct page **page_ptr; /* pointer to the current page */
208 };
209
210 /*
211 * These are the xdr_stream style generic XDR encode and decode functions.
212 */
213 typedef void (*kxdreproc_t)(void *rqstp, struct xdr_stream *xdr, void *obj);
214 typedef int (*kxdrdproc_t)(void *rqstp, struct xdr_stream *xdr, void *obj);
215
216 extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
217 extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes);
218 extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages,
219 unsigned int base, unsigned int len);
220 extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
221 extern void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf,
222 struct page **pages, unsigned int len);
223 extern void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen);
224 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
225 extern void xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
226 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
227 extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);
228
229 #endif /* __KERNEL__ */
230
231 #endif /* _SUNRPC_XDR_H_ */
232