include/linux/ceph/decode.h

   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 #define ceph_decode_need(p, end, n, bad)                \
  50         do {                                            \
  51                 if (unlikely(*(p) + (n) > (end)))       \
  52                         goto bad;                       \
  53         } while (0)
  54
  55 #define ceph_decode_64_safe(p, end, v, bad)                     \
  56         do {                                                    \
  57                 ceph_decode_need(p, end, sizeof(u64), bad);     \
  58                 v = ceph_decode_64(p);                          \
  59         } while (0)
  60 #define ceph_decode_32_safe(p, end, v, bad)                     \
  61         do {                                                    \
  62                 ceph_decode_need(p, end, sizeof(u32), bad);     \
  63                 v = ceph_decode_32(p);                          \
  64         } while (0)
  65 #define ceph_decode_16_safe(p, end, v, bad)                     \
  66         do {                                                    \
  67                 ceph_decode_need(p, end, sizeof(u16), bad);     \
  68                 v = ceph_decode_16(p);                          \
  69         } while (0)
  70 #define ceph_decode_8_safe(p, end, v, bad)                      \
  71         do {                                                    \
  72                 ceph_decode_need(p, end, sizeof(u8), bad);      \
  73                 v = ceph_decode_8(p);                           \
  74         } while (0)
  75
  76 #define ceph_decode_copy_safe(p, end, pv, n, bad)               \
  77         do {                                                    \
  78                 ceph_decode_need(p, end, n, bad);               \
  79                 ceph_decode_copy(p, pv, n);                     \
  80         } while (0)
  81
  82 /*
  83  * struct ceph_timespec <-> struct timespec
  84  */
  85 static inline void ceph_decode_timespec(struct timespec *ts,
  86                                         const struct ceph_timespec *tv)
  87 {
  88         ts->tv_sec = le32_to_cpu(tv->tv_sec);
  89         ts->tv_nsec = le32_to_cpu(tv->tv_nsec);
  90 }
  91 static inline void ceph_encode_timespec(struct ceph_timespec *tv,
  92                                         const struct timespec *ts)
  93 {
  94         tv->tv_sec = cpu_to_le32(ts->tv_sec);
  95         tv->tv_nsec = cpu_to_le32(ts->tv_nsec);
  96 }
  97
  98 /*
  99  * sockaddr_storage <-> ceph_sockaddr
 100  */
 101 static inline void ceph_encode_addr(struct ceph_entity_addr *a)
 102 {
 103         __be16 ss_family = htons(a->in_addr.ss_family);
 104         a->in_addr.ss_family = *(__u16 *)&ss_family;
 105 }
 106 static inline void ceph_decode_addr(struct ceph_entity_addr *a)
 107 {
 108         __be16 ss_family = *(__be16 *)&a->in_addr.ss_family;
 109         a->in_addr.ss_family = ntohs(ss_family);
 110         WARN_ON(a->in_addr.ss_family == 512);
 111 }
 112
 113 /*
 114  * encoders
 115  */
 116 static inline void ceph_encode_64(void **p, u64 v)
 117 {
 118         put_unaligned_le64(v, (__le64 *)*p);
 119         *p += sizeof(u64);
 120 }
 121 static inline void ceph_encode_32(void **p, u32 v)
 122 {
 123         put_unaligned_le32(v, (__le32 *)*p);
 124         *p += sizeof(u32);
 125 }
 126 static inline void ceph_encode_16(void **p, u16 v)
 127 {
 128         put_unaligned_le16(v, (__le16 *)*p);
 129         *p += sizeof(u16);
 130 }
 131 static inline void ceph_encode_8(void **p, u8 v)
 132 {
 133         *(u8 *)*p = v;
 134         (*p)++;
 135 }
 136 static inline void ceph_encode_copy(void **p, const void *s, int len)
 137 {
 138         memcpy(*p, s, len);
 139         *p += len;
 140 }
 141
 142 /*
 143  * filepath, string encoders
 144  */
 145 static inline void ceph_encode_filepath(void **p, void *end,
 146                                         u64 ino, const char *path)
 147 {
 148         u32 len = path ? strlen(path) : 0;
 149         BUG_ON(*p + sizeof(ino) + sizeof(len) + len > end);
 150         ceph_encode_8(p, 1);
 151         ceph_encode_64(p, ino);
 152         ceph_encode_32(p, len);
 153         if (len)
 154                 memcpy(*p, path, len);
 155         *p += len;
 156 }
 157
 158 static inline void ceph_encode_string(void **p, void *end,
 159                                       const char *s, u32 len)
 160 {
 161         BUG_ON(*p + sizeof(len) + len > end);
 162         ceph_encode_32(p, len);
 163         if (len)
 164                 memcpy(*p, s, len);
 165         *p += len;
 166 }
 167
 168 #define ceph_encode_need(p, end, n, bad)                \
 169         do {                                            \
 170                 if (unlikely(*(p) + (n) > (end)))       \
 171                         goto bad;                       \
 172         } while (0)
 173
 174 #define ceph_encode_64_safe(p, end, v, bad)                     \
 175         do {                                                    \
 176                 ceph_encode_need(p, end, sizeof(u64), bad);     \
 177                 ceph_encode_64(p, v);                           \
 178         } while (0)
 179 #define ceph_encode_32_safe(p, end, v, bad)                     \
 180         do {                                                    \
 181                 ceph_encode_need(p, end, sizeof(u32), bad);     \
 182                 ceph_encode_32(p, v);                   \
 183         } while (0)
 184 #define ceph_encode_16_safe(p, end, v, bad)                     \
 185         do {                                                    \
 186                 ceph_encode_need(p, end, sizeof(u16), bad);     \
 187                 ceph_encode_16(p, v);                   \
 188         } while (0)
 189
 190 #define ceph_encode_copy_safe(p, end, pv, n, bad)               \
 191         do {                                                    \
 192                 ceph_encode_need(p, end, n, bad);               \
 193                 ceph_encode_copy(p, pv, n);                     \
 194         } while (0)
 195 #define ceph_encode_string_safe(p, end, s, n, bad)              \
 196         do {                                                    \
 197                 ceph_encode_need(p, end, n, bad);               \
 198                 ceph_encode_string(p, end, s, n);               \
 199         } while (0)
 200
 201
 202 #endif