xref: /linux-6.15/include/linux/ceph/decode.h (revision d89dffa9)
1 #ifndef __CEPH_DECODE_H
2 #define __CEPH_DECODE_H
3 
4 #include <linux/bug.h>
5 #include <linux/time.h>
6 #include <asm/unaligned.h>
7 
8 #include "types.h"
9 
10 /*
11  * in all cases,
12  *   void **p     pointer to position pointer
13  *   void *end    pointer to end of buffer (last byte + 1)
14  */
15 
16 static inline u64 ceph_decode_64(void **p)
17 {
18 	u64 v = get_unaligned_le64(*p);
19 	*p += sizeof(u64);
20 	return v;
21 }
22 static inline u32 ceph_decode_32(void **p)
23 {
24 	u32 v = get_unaligned_le32(*p);
25 	*p += sizeof(u32);
26 	return v;
27 }
28 static inline u16 ceph_decode_16(void **p)
29 {
30 	u16 v = get_unaligned_le16(*p);
31 	*p += sizeof(u16);
32 	return v;
33 }
34 static inline u8 ceph_decode_8(void **p)
35 {
36 	u8 v = *(u8 *)*p;
37 	(*p)++;
38 	return v;
39 }
40 static inline void ceph_decode_copy(void **p, void *pv, size_t n)
41 {
42 	memcpy(pv, *p, n);
43 	*p += n;
44 }
45 
46 /*
47  * bounds check input.
48  */
49 static inline int ceph_has_room(void **p, void *end, size_t n)
50 {
51 	return end >= *p && n <= end - *p;
52 }
53 
54 #define ceph_decode_need(p, end, n, bad)		\
55 	do {						\
56 		if (!likely(ceph_has_room(p, end, n)))	\
57 			goto bad;			\
58 	} while (0)
59 
60 #define ceph_decode_64_safe(p, end, v, bad)			\
61 	do {							\
62 		ceph_decode_need(p, end, sizeof(u64), bad);	\
63 		v = ceph_decode_64(p);				\
64 	} while (0)
65 #define ceph_decode_32_safe(p, end, v, bad)			\
66 	do {							\
67 		ceph_decode_need(p, end, sizeof(u32), bad);	\
68 		v = ceph_decode_32(p);				\
69 	} while (0)
70 #define ceph_decode_16_safe(p, end, v, bad)			\
71 	do {							\
72 		ceph_decode_need(p, end, sizeof(u16), bad);	\
73 		v = ceph_decode_16(p);				\
74 	} while (0)
75 #define ceph_decode_8_safe(p, end, v, bad)			\
76 	do {							\
77 		ceph_decode_need(p, end, sizeof(u8), bad);	\
78 		v = ceph_decode_8(p);				\
79 	} while (0)
80 
81 #define ceph_decode_copy_safe(p, end, pv, n, bad)		\
82 	do {							\
83 		ceph_decode_need(p, end, n, bad);		\
84 		ceph_decode_copy(p, pv, n);			\
85 	} while (0)
86 
87 /*
88  * struct ceph_timespec <-> struct timespec
89  */
90 static inline void ceph_decode_timespec(struct timespec *ts,
91 					const struct ceph_timespec *tv)
92 {
93 	ts->tv_sec = le32_to_cpu(tv->tv_sec);
94 	ts->tv_nsec = le32_to_cpu(tv->tv_nsec);
95 }
96 static inline void ceph_encode_timespec(struct ceph_timespec *tv,
97 					const struct timespec *ts)
98 {
99 	tv->tv_sec = cpu_to_le32(ts->tv_sec);
100 	tv->tv_nsec = cpu_to_le32(ts->tv_nsec);
101 }
102 
103 /*
104  * sockaddr_storage <-> ceph_sockaddr
105  */
106 static inline void ceph_encode_addr(struct ceph_entity_addr *a)
107 {
108 	__be16 ss_family = htons(a->in_addr.ss_family);
109 	a->in_addr.ss_family = *(__u16 *)&ss_family;
110 }
111 static inline void ceph_decode_addr(struct ceph_entity_addr *a)
112 {
113 	__be16 ss_family = *(__be16 *)&a->in_addr.ss_family;
114 	a->in_addr.ss_family = ntohs(ss_family);
115 	WARN_ON(a->in_addr.ss_family == 512);
116 }
117 
118 /*
119  * encoders
120  */
121 static inline void ceph_encode_64(void **p, u64 v)
122 {
123 	put_unaligned_le64(v, (__le64 *)*p);
124 	*p += sizeof(u64);
125 }
126 static inline void ceph_encode_32(void **p, u32 v)
127 {
128 	put_unaligned_le32(v, (__le32 *)*p);
129 	*p += sizeof(u32);
130 }
131 static inline void ceph_encode_16(void **p, u16 v)
132 {
133 	put_unaligned_le16(v, (__le16 *)*p);
134 	*p += sizeof(u16);
135 }
136 static inline void ceph_encode_8(void **p, u8 v)
137 {
138 	*(u8 *)*p = v;
139 	(*p)++;
140 }
141 static inline void ceph_encode_copy(void **p, const void *s, int len)
142 {
143 	memcpy(*p, s, len);
144 	*p += len;
145 }
146 
147 /*
148  * filepath, string encoders
149  */
150 static inline void ceph_encode_filepath(void **p, void *end,
151 					u64 ino, const char *path)
152 {
153 	u32 len = path ? strlen(path) : 0;
154 	BUG_ON(*p + sizeof(ino) + sizeof(len) + len > end);
155 	ceph_encode_8(p, 1);
156 	ceph_encode_64(p, ino);
157 	ceph_encode_32(p, len);
158 	if (len)
159 		memcpy(*p, path, len);
160 	*p += len;
161 }
162 
163 static inline void ceph_encode_string(void **p, void *end,
164 				      const char *s, u32 len)
165 {
166 	BUG_ON(*p + sizeof(len) + len > end);
167 	ceph_encode_32(p, len);
168 	if (len)
169 		memcpy(*p, s, len);
170 	*p += len;
171 }
172 
173 #define ceph_encode_need(p, end, n, bad)		\
174 	do {						\
175 		if (!likely(ceph_has_room(p, end, n)))	\
176 			goto bad;			\
177 	} while (0)
178 
179 #define ceph_encode_64_safe(p, end, v, bad)			\
180 	do {							\
181 		ceph_encode_need(p, end, sizeof(u64), bad);	\
182 		ceph_encode_64(p, v);				\
183 	} while (0)
184 #define ceph_encode_32_safe(p, end, v, bad)			\
185 	do {							\
186 		ceph_encode_need(p, end, sizeof(u32), bad);	\
187 		ceph_encode_32(p, v);			\
188 	} while (0)
189 #define ceph_encode_16_safe(p, end, v, bad)			\
190 	do {							\
191 		ceph_encode_need(p, end, sizeof(u16), bad);	\
192 		ceph_encode_16(p, v);			\
193 	} while (0)
194 
195 #define ceph_encode_copy_safe(p, end, pv, n, bad)		\
196 	do {							\
197 		ceph_encode_need(p, end, n, bad);		\
198 		ceph_encode_copy(p, pv, n);			\
199 	} while (0)
200 #define ceph_encode_string_safe(p, end, s, n, bad)		\
201 	do {							\
202 		ceph_encode_need(p, end, n, bad);		\
203 		ceph_encode_string(p, end, s, n);		\
204 	} while (0)
205 
206 
207 #endif
208