xref: /linux-6.15/include/linux/ceph/decode.h (revision 76aa542f)
1 #ifndef __CEPH_DECODE_H
2 #define __CEPH_DECODE_H
3 
4 #include <asm/unaligned.h>
5 #include <linux/time.h>
6 
7 #include "types.h"
8 
9 /*
10  * in all cases,
11  *   void **p     pointer to position pointer
12  *   void *end    pointer to end of buffer (last byte + 1)
13  */
14 
15 static inline u64 ceph_decode_64(void **p)
16 {
17 	u64 v = get_unaligned_le64(*p);
18 	*p += sizeof(u64);
19 	return v;
20 }
21 static inline u32 ceph_decode_32(void **p)
22 {
23 	u32 v = get_unaligned_le32(*p);
24 	*p += sizeof(u32);
25 	return v;
26 }
27 static inline u16 ceph_decode_16(void **p)
28 {
29 	u16 v = get_unaligned_le16(*p);
30 	*p += sizeof(u16);
31 	return v;
32 }
33 static inline u8 ceph_decode_8(void **p)
34 {
35 	u8 v = *(u8 *)*p;
36 	(*p)++;
37 	return v;
38 }
39 static inline void ceph_decode_copy(void **p, void *pv, size_t n)
40 {
41 	memcpy(pv, *p, n);
42 	*p += n;
43 }
44 
45 /*
46  * bounds check input.
47  */
48 static inline int ceph_has_room(void **p, void *end, size_t n)
49 {
50 	return end >= *p && n <= end - *p;
51 }
52 
53 #define ceph_decode_need(p, end, n, bad)		\
54 	do {						\
55 		if (!likely(ceph_has_room(p, end, n)))	\
56 			goto bad;			\
57 	} while (0)
58 
59 #define ceph_decode_64_safe(p, end, v, bad)			\
60 	do {							\
61 		ceph_decode_need(p, end, sizeof(u64), bad);	\
62 		v = ceph_decode_64(p);				\
63 	} while (0)
64 #define ceph_decode_32_safe(p, end, v, bad)			\
65 	do {							\
66 		ceph_decode_need(p, end, sizeof(u32), bad);	\
67 		v = ceph_decode_32(p);				\
68 	} while (0)
69 #define ceph_decode_16_safe(p, end, v, bad)			\
70 	do {							\
71 		ceph_decode_need(p, end, sizeof(u16), bad);	\
72 		v = ceph_decode_16(p);				\
73 	} while (0)
74 #define ceph_decode_8_safe(p, end, v, bad)			\
75 	do {							\
76 		ceph_decode_need(p, end, sizeof(u8), bad);	\
77 		v = ceph_decode_8(p);				\
78 	} while (0)
79 
80 #define ceph_decode_copy_safe(p, end, pv, n, bad)		\
81 	do {							\
82 		ceph_decode_need(p, end, n, bad);		\
83 		ceph_decode_copy(p, pv, n);			\
84 	} while (0)
85 
86 /*
87  * struct ceph_timespec <-> struct timespec
88  */
89 static inline void ceph_decode_timespec(struct timespec *ts,
90 					const struct ceph_timespec *tv)
91 {
92 	ts->tv_sec = le32_to_cpu(tv->tv_sec);
93 	ts->tv_nsec = le32_to_cpu(tv->tv_nsec);
94 }
95 static inline void ceph_encode_timespec(struct ceph_timespec *tv,
96 					const struct timespec *ts)
97 {
98 	tv->tv_sec = cpu_to_le32(ts->tv_sec);
99 	tv->tv_nsec = cpu_to_le32(ts->tv_nsec);
100 }
101 
102 /*
103  * sockaddr_storage <-> ceph_sockaddr
104  */
105 static inline void ceph_encode_addr(struct ceph_entity_addr *a)
106 {
107 	__be16 ss_family = htons(a->in_addr.ss_family);
108 	a->in_addr.ss_family = *(__u16 *)&ss_family;
109 }
110 static inline void ceph_decode_addr(struct ceph_entity_addr *a)
111 {
112 	__be16 ss_family = *(__be16 *)&a->in_addr.ss_family;
113 	a->in_addr.ss_family = ntohs(ss_family);
114 	WARN_ON(a->in_addr.ss_family == 512);
115 }
116 
117 /*
118  * encoders
119  */
120 static inline void ceph_encode_64(void **p, u64 v)
121 {
122 	put_unaligned_le64(v, (__le64 *)*p);
123 	*p += sizeof(u64);
124 }
125 static inline void ceph_encode_32(void **p, u32 v)
126 {
127 	put_unaligned_le32(v, (__le32 *)*p);
128 	*p += sizeof(u32);
129 }
130 static inline void ceph_encode_16(void **p, u16 v)
131 {
132 	put_unaligned_le16(v, (__le16 *)*p);
133 	*p += sizeof(u16);
134 }
135 static inline void ceph_encode_8(void **p, u8 v)
136 {
137 	*(u8 *)*p = v;
138 	(*p)++;
139 }
140 static inline void ceph_encode_copy(void **p, const void *s, int len)
141 {
142 	memcpy(*p, s, len);
143 	*p += len;
144 }
145 
146 /*
147  * filepath, string encoders
148  */
149 static inline void ceph_encode_filepath(void **p, void *end,
150 					u64 ino, const char *path)
151 {
152 	u32 len = path ? strlen(path) : 0;
153 	BUG_ON(*p + sizeof(ino) + sizeof(len) + len > end);
154 	ceph_encode_8(p, 1);
155 	ceph_encode_64(p, ino);
156 	ceph_encode_32(p, len);
157 	if (len)
158 		memcpy(*p, path, len);
159 	*p += len;
160 }
161 
162 static inline void ceph_encode_string(void **p, void *end,
163 				      const char *s, u32 len)
164 {
165 	BUG_ON(*p + sizeof(len) + len > end);
166 	ceph_encode_32(p, len);
167 	if (len)
168 		memcpy(*p, s, len);
169 	*p += len;
170 }
171 
172 #define ceph_encode_need(p, end, n, bad)		\
173 	do {						\
174 		if (!likely(ceph_has_room(p, end, n)))	\
175 			goto bad;			\
176 	} while (0)
177 
178 #define ceph_encode_64_safe(p, end, v, bad)			\
179 	do {							\
180 		ceph_encode_need(p, end, sizeof(u64), bad);	\
181 		ceph_encode_64(p, v);				\
182 	} while (0)
183 #define ceph_encode_32_safe(p, end, v, bad)			\
184 	do {							\
185 		ceph_encode_need(p, end, sizeof(u32), bad);	\
186 		ceph_encode_32(p, v);			\
187 	} while (0)
188 #define ceph_encode_16_safe(p, end, v, bad)			\
189 	do {							\
190 		ceph_encode_need(p, end, sizeof(u16), bad);	\
191 		ceph_encode_16(p, v);			\
192 	} while (0)
193 
194 #define ceph_encode_copy_safe(p, end, pv, n, bad)		\
195 	do {							\
196 		ceph_encode_need(p, end, n, bad);		\
197 		ceph_encode_copy(p, pv, n);			\
198 	} while (0)
199 #define ceph_encode_string_safe(p, end, s, n, bad)		\
200 	do {							\
201 		ceph_encode_need(p, end, n, bad);		\
202 		ceph_encode_string(p, end, s, n);		\
203 	} while (0)
204 
205 
206 #endif
207