315 lines
7.5 KiB
C
315 lines
7.5 KiB
C
#ifndef __CEPH_DECODE_H
|
|
#define __CEPH_DECODE_H
|
|
|
|
#include <linux/err.h>
|
|
#include <linux/bug.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/time.h>
|
|
#include <asm/unaligned.h>
|
|
|
|
#include <linux/ceph/types.h>
|
|
|
|
/*
|
|
* in all cases,
|
|
* void **p pointer to position pointer
|
|
* void *end pointer to end of buffer (last byte + 1)
|
|
*/
|
|
|
|
static inline u64 ceph_decode_64(void **p)
|
|
{
|
|
u64 v = get_unaligned_le64(*p);
|
|
*p += sizeof(u64);
|
|
return v;
|
|
}
|
|
static inline u32 ceph_decode_32(void **p)
|
|
{
|
|
u32 v = get_unaligned_le32(*p);
|
|
*p += sizeof(u32);
|
|
return v;
|
|
}
|
|
static inline u16 ceph_decode_16(void **p)
|
|
{
|
|
u16 v = get_unaligned_le16(*p);
|
|
*p += sizeof(u16);
|
|
return v;
|
|
}
|
|
static inline u8 ceph_decode_8(void **p)
|
|
{
|
|
u8 v = *(u8 *)*p;
|
|
(*p)++;
|
|
return v;
|
|
}
|
|
static inline void ceph_decode_copy(void **p, void *pv, size_t n)
|
|
{
|
|
memcpy(pv, *p, n);
|
|
*p += n;
|
|
}
|
|
|
|
/*
|
|
* bounds check input.
|
|
*/
|
|
static inline bool ceph_has_room(void **p, void *end, size_t n)
|
|
{
|
|
return end >= *p && n <= end - *p;
|
|
}
|
|
|
|
#define ceph_decode_need(p, end, n, bad) \
|
|
do { \
|
|
if (!likely(ceph_has_room(p, end, n))) \
|
|
goto bad; \
|
|
} while (0)
|
|
|
|
#define ceph_decode_64_safe(p, end, v, bad) \
|
|
do { \
|
|
ceph_decode_need(p, end, sizeof(u64), bad); \
|
|
v = ceph_decode_64(p); \
|
|
} while (0)
|
|
#define ceph_decode_32_safe(p, end, v, bad) \
|
|
do { \
|
|
ceph_decode_need(p, end, sizeof(u32), bad); \
|
|
v = ceph_decode_32(p); \
|
|
} while (0)
|
|
#define ceph_decode_16_safe(p, end, v, bad) \
|
|
do { \
|
|
ceph_decode_need(p, end, sizeof(u16), bad); \
|
|
v = ceph_decode_16(p); \
|
|
} while (0)
|
|
#define ceph_decode_8_safe(p, end, v, bad) \
|
|
do { \
|
|
ceph_decode_need(p, end, sizeof(u8), bad); \
|
|
v = ceph_decode_8(p); \
|
|
} while (0)
|
|
|
|
#define ceph_decode_copy_safe(p, end, pv, n, bad) \
|
|
do { \
|
|
ceph_decode_need(p, end, n, bad); \
|
|
ceph_decode_copy(p, pv, n); \
|
|
} while (0)
|
|
|
|
/*
|
|
* Allocate a buffer big enough to hold the wire-encoded string, and
|
|
* decode the string into it. The resulting string will always be
|
|
* terminated with '\0'. If successful, *p will be advanced
|
|
* past the decoded data. Also, if lenp is not a null pointer, the
|
|
* length (not including the terminating '\0') will be recorded in
|
|
* *lenp. Note that a zero-length string is a valid return value.
|
|
*
|
|
* Returns a pointer to the newly-allocated string buffer, or a
|
|
* pointer-coded errno if an error occurs. Neither *p nor *lenp
|
|
* will have been updated if an error is returned.
|
|
*
|
|
* There are two possible failures:
|
|
* - converting the string would require accessing memory at or
|
|
* beyond the "end" pointer provided (-ERANGE)
|
|
* - memory could not be allocated for the result (-ENOMEM)
|
|
*/
|
|
static inline char *ceph_extract_encoded_string(void **p, void *end,
|
|
size_t *lenp, gfp_t gfp)
|
|
{
|
|
u32 len;
|
|
void *sp = *p;
|
|
char *buf;
|
|
|
|
ceph_decode_32_safe(&sp, end, len, bad);
|
|
if (!ceph_has_room(&sp, end, len))
|
|
goto bad;
|
|
|
|
buf = kmalloc(len + 1, gfp);
|
|
if (!buf)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
if (len)
|
|
memcpy(buf, sp, len);
|
|
buf[len] = '\0';
|
|
|
|
*p = (char *) *p + sizeof (u32) + len;
|
|
if (lenp)
|
|
*lenp = (size_t) len;
|
|
|
|
return buf;
|
|
|
|
bad:
|
|
return ERR_PTR(-ERANGE);
|
|
}
|
|
|
|
/*
|
|
* struct ceph_timespec <-> struct timespec
|
|
*/
|
|
static inline void ceph_decode_timespec(struct timespec *ts,
|
|
const struct ceph_timespec *tv)
|
|
{
|
|
ts->tv_sec = (__kernel_time_t)le32_to_cpu(tv->tv_sec);
|
|
ts->tv_nsec = (long)le32_to_cpu(tv->tv_nsec);
|
|
}
|
|
static inline void ceph_encode_timespec(struct ceph_timespec *tv,
|
|
const struct timespec *ts)
|
|
{
|
|
tv->tv_sec = cpu_to_le32((u32)ts->tv_sec);
|
|
tv->tv_nsec = cpu_to_le32((u32)ts->tv_nsec);
|
|
}
|
|
|
|
/*
|
|
* sockaddr_storage <-> ceph_sockaddr
|
|
*/
|
|
static inline void ceph_encode_addr(struct ceph_entity_addr *a)
|
|
{
|
|
__be16 ss_family = htons(a->in_addr.ss_family);
|
|
a->in_addr.ss_family = *(__u16 *)&ss_family;
|
|
}
|
|
static inline void ceph_decode_addr(struct ceph_entity_addr *a)
|
|
{
|
|
__be16 ss_family = *(__be16 *)&a->in_addr.ss_family;
|
|
a->in_addr.ss_family = ntohs(ss_family);
|
|
WARN_ON(a->in_addr.ss_family == 512);
|
|
}
|
|
|
|
/*
|
|
* encoders
|
|
*/
|
|
static inline void ceph_encode_64(void **p, u64 v)
|
|
{
|
|
put_unaligned_le64(v, (__le64 *)*p);
|
|
*p += sizeof(u64);
|
|
}
|
|
static inline void ceph_encode_32(void **p, u32 v)
|
|
{
|
|
put_unaligned_le32(v, (__le32 *)*p);
|
|
*p += sizeof(u32);
|
|
}
|
|
static inline void ceph_encode_16(void **p, u16 v)
|
|
{
|
|
put_unaligned_le16(v, (__le16 *)*p);
|
|
*p += sizeof(u16);
|
|
}
|
|
static inline void ceph_encode_8(void **p, u8 v)
|
|
{
|
|
*(u8 *)*p = v;
|
|
(*p)++;
|
|
}
|
|
static inline void ceph_encode_copy(void **p, const void *s, int len)
|
|
{
|
|
memcpy(*p, s, len);
|
|
*p += len;
|
|
}
|
|
|
|
/*
|
|
* filepath, string encoders
|
|
*/
|
|
static inline void ceph_encode_filepath(void **p, void *end,
|
|
u64 ino, const char *path)
|
|
{
|
|
u32 len = path ? strlen(path) : 0;
|
|
BUG_ON(*p + 1 + sizeof(ino) + sizeof(len) + len > end);
|
|
ceph_encode_8(p, 1);
|
|
ceph_encode_64(p, ino);
|
|
ceph_encode_32(p, len);
|
|
if (len)
|
|
memcpy(*p, path, len);
|
|
*p += len;
|
|
}
|
|
|
|
static inline void ceph_encode_string(void **p, void *end,
|
|
const char *s, u32 len)
|
|
{
|
|
BUG_ON(*p + sizeof(len) + len > end);
|
|
ceph_encode_32(p, len);
|
|
if (len)
|
|
memcpy(*p, s, len);
|
|
*p += len;
|
|
}
|
|
|
|
/*
|
|
* version and length starting block encoders/decoders
|
|
*/
|
|
|
|
/* current code version (u8) + compat code version (u8) + len of struct (u32) */
|
|
#define CEPH_ENCODING_START_BLK_LEN 6
|
|
|
|
/**
|
|
* ceph_start_encoding - start encoding block
|
|
* @struct_v: current (code) version of the encoding
|
|
* @struct_compat: oldest code version that can decode it
|
|
* @struct_len: length of struct encoding
|
|
*/
|
|
static inline void ceph_start_encoding(void **p, u8 struct_v, u8 struct_compat,
|
|
u32 struct_len)
|
|
{
|
|
ceph_encode_8(p, struct_v);
|
|
ceph_encode_8(p, struct_compat);
|
|
ceph_encode_32(p, struct_len);
|
|
}
|
|
|
|
/**
|
|
* ceph_start_decoding - start decoding block
|
|
* @v: current version of the encoding that the code supports
|
|
* @name: name of the struct (free-form)
|
|
* @struct_v: out param for the encoding version
|
|
* @struct_len: out param for the length of struct encoding
|
|
*
|
|
* Validates the length of struct encoding, so unsafe ceph_decode_*
|
|
* variants can be used for decoding.
|
|
*/
|
|
static inline int ceph_start_decoding(void **p, void *end, u8 v,
|
|
const char *name, u8 *struct_v,
|
|
u32 *struct_len)
|
|
{
|
|
u8 struct_compat;
|
|
|
|
ceph_decode_need(p, end, CEPH_ENCODING_START_BLK_LEN, bad);
|
|
*struct_v = ceph_decode_8(p);
|
|
struct_compat = ceph_decode_8(p);
|
|
if (v < struct_compat) {
|
|
pr_warn("got struct_v %d struct_compat %d > %d of %s\n",
|
|
*struct_v, struct_compat, v, name);
|
|
return -EINVAL;
|
|
}
|
|
|
|
*struct_len = ceph_decode_32(p);
|
|
ceph_decode_need(p, end, *struct_len, bad);
|
|
return 0;
|
|
|
|
bad:
|
|
return -ERANGE;
|
|
}
|
|
|
|
#define ceph_encode_need(p, end, n, bad) \
|
|
do { \
|
|
if (!likely(ceph_has_room(p, end, n))) \
|
|
goto bad; \
|
|
} while (0)
|
|
|
|
#define ceph_encode_64_safe(p, end, v, bad) \
|
|
do { \
|
|
ceph_encode_need(p, end, sizeof(u64), bad); \
|
|
ceph_encode_64(p, v); \
|
|
} while (0)
|
|
#define ceph_encode_32_safe(p, end, v, bad) \
|
|
do { \
|
|
ceph_encode_need(p, end, sizeof(u32), bad); \
|
|
ceph_encode_32(p, v); \
|
|
} while (0)
|
|
#define ceph_encode_16_safe(p, end, v, bad) \
|
|
do { \
|
|
ceph_encode_need(p, end, sizeof(u16), bad); \
|
|
ceph_encode_16(p, v); \
|
|
} while (0)
|
|
#define ceph_encode_8_safe(p, end, v, bad) \
|
|
do { \
|
|
ceph_encode_need(p, end, sizeof(u8), bad); \
|
|
ceph_encode_8(p, v); \
|
|
} while (0)
|
|
|
|
#define ceph_encode_copy_safe(p, end, pv, n, bad) \
|
|
do { \
|
|
ceph_encode_need(p, end, n, bad); \
|
|
ceph_encode_copy(p, pv, n); \
|
|
} while (0)
|
|
#define ceph_encode_string_safe(p, end, s, n, bad) \
|
|
do { \
|
|
ceph_encode_need(p, end, n, bad); \
|
|
ceph_encode_string(p, end, s, n); \
|
|
} while (0)
|
|
|
|
|
|
#endif
|