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 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_inline_pages(struct xdr_buf *, unsigned int,
108 struct page **, unsigned int, unsigned int);
109 void xdr_terminate_string(struct xdr_buf *, const u32);
110
xdr_encode_array(__be32 * p,const void * s,unsigned int len)111 static inline __be32 *xdr_encode_array(__be32 *p, const void *s, unsigned int len)
112 {
113 return xdr_encode_opaque(p, s, len);
114 }
115
116 /*
117 * Decode 64bit quantities (NFSv3 support)
118 */
119 static inline __be32 *
xdr_encode_hyper(__be32 * p,__u64 val)120 xdr_encode_hyper(__be32 *p, __u64 val)
121 {
122 put_unaligned_be64(val, p);
123 return p + 2;
124 }
125
126 static inline __be32 *
xdr_decode_hyper(__be32 * p,__u64 * valp)127 xdr_decode_hyper(__be32 *p, __u64 *valp)
128 {
129 *valp = get_unaligned_be64(p);
130 return p + 2;
131 }
132
133 static inline __be32 *
xdr_decode_opaque_fixed(__be32 * p,void * ptr,unsigned int len)134 xdr_decode_opaque_fixed(__be32 *p, void *ptr, unsigned int len)
135 {
136 memcpy(ptr, p, len);
137 return p + XDR_QUADLEN(len);
138 }
139
140 /*
141 * Adjust kvec to reflect end of xdr'ed data (RPC client XDR)
142 */
143 static inline int
xdr_adjust_iovec(struct kvec * iov,__be32 * p)144 xdr_adjust_iovec(struct kvec *iov, __be32 *p)
145 {
146 return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base);
147 }
148
149 /*
150 * XDR buffer helper functions
151 */
152 extern void xdr_shift_buf(struct xdr_buf *, size_t);
153 extern void xdr_buf_from_iov(struct kvec *, struct xdr_buf *);
154 extern int xdr_buf_subsegment(struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int);
155 extern void xdr_buf_trim(struct xdr_buf *, unsigned int);
156 extern int xdr_buf_read_netobj(struct xdr_buf *, struct xdr_netobj *, unsigned int);
157 extern int read_bytes_from_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
158 extern int write_bytes_to_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
159
160 /*
161 * Helper structure for copying from an sk_buff.
162 */
163 struct xdr_skb_reader {
164 struct sk_buff *skb;
165 unsigned int offset;
166 size_t count;
167 __wsum csum;
168 };
169
170 typedef size_t (*xdr_skb_read_actor)(struct xdr_skb_reader *desc, void *to, size_t len);
171
172 size_t xdr_skb_read_bits(struct xdr_skb_reader *desc, void *to, size_t len);
173 extern int csum_partial_copy_to_xdr(struct xdr_buf *, struct sk_buff *);
174 extern ssize_t xdr_partial_copy_from_skb(struct xdr_buf *, unsigned int,
175 struct xdr_skb_reader *, xdr_skb_read_actor);
176
177 extern int xdr_encode_word(struct xdr_buf *, unsigned int, u32);
178 extern int xdr_decode_word(struct xdr_buf *, unsigned int, u32 *);
179
180 struct xdr_array2_desc;
181 typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem);
182 struct xdr_array2_desc {
183 unsigned int elem_size;
184 unsigned int array_len;
185 unsigned int array_maxlen;
186 xdr_xcode_elem_t xcode;
187 };
188
189 extern int xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
190 struct xdr_array2_desc *desc);
191 extern int xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
192 struct xdr_array2_desc *desc);
193 extern void _copy_from_pages(char *p, struct page **pages, size_t pgbase,
194 size_t len);
195
196 /*
197 * Provide some simple tools for XDR buffer overflow-checking etc.
198 */
199 struct xdr_stream {
200 __be32 *p; /* start of available buffer */
201 struct xdr_buf *buf; /* XDR buffer to read/write */
202
203 __be32 *end; /* end of available buffer space */
204 struct kvec *iov; /* pointer to the current kvec */
205 struct kvec scratch; /* Scratch buffer */
206 struct page **page_ptr; /* pointer to the current page */
207 unsigned int nwords; /* Remaining decode buffer length */
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 unsigned int xdr_stream_pos(const struct xdr_stream *xdr);
221 extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
222 extern void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf,
223 struct page **pages, unsigned int len);
224 extern void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen);
225 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
226 extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
227 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
228 extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);
229
230 #endif /* __KERNEL__ */
231
232 #endif /* _SUNRPC_XDR_H_ */
233