bcachefs-tools/libbcachefs/checksum.h
2017-03-19 17:31:47 -08:00

134 lines
3.4 KiB
C

#ifndef _BCACHE_CHECKSUM_H
#define _BCACHE_CHECKSUM_H
#include "bcachefs.h"
#include "super-io.h"
#include <crypto/chacha20.h>
u64 bch2_crc64_update(u64, const void *, size_t);
#define BCH_NONCE_EXTENT cpu_to_le32(1 << 28)
#define BCH_NONCE_BTREE cpu_to_le32(2 << 28)
#define BCH_NONCE_JOURNAL cpu_to_le32(3 << 28)
#define BCH_NONCE_PRIO cpu_to_le32(4 << 28)
#define BCH_NONCE_POLY cpu_to_le32(1 << 31)
struct bch_csum bch2_checksum(struct bch_fs *, unsigned, struct nonce,
const void *, size_t);
/*
* This is used for various on disk data structures - bch_sb, prio_set, bset,
* jset: The checksum is _always_ the first field of these structs
*/
#define csum_vstruct(_c, _type, _nonce, _i) \
({ \
const void *start = ((const void *) (_i)) + sizeof((_i)->csum); \
const void *end = vstruct_end(_i); \
\
bch2_checksum(_c, _type, _nonce, start, end - start); \
})
int bch2_chacha_encrypt_key(struct bch_key *, struct nonce, void *, size_t);
int bch2_request_key(struct bch_sb *, struct bch_key *);
void bch2_encrypt(struct bch_fs *, unsigned, struct nonce,
void *data, size_t);
struct bch_csum bch2_checksum_bio(struct bch_fs *, unsigned,
struct nonce, struct bio *);
void bch2_encrypt_bio(struct bch_fs *, unsigned,
struct nonce, struct bio *);
int bch2_disable_encryption(struct bch_fs *);
int bch2_enable_encryption(struct bch_fs *, bool);
void bch2_fs_encryption_exit(struct bch_fs *);
int bch2_fs_encryption_init(struct bch_fs *);
static inline unsigned bch2_data_checksum_type(struct bch_fs *c)
{
if (c->sb.encryption_type)
return c->opts.wide_macs
? BCH_CSUM_CHACHA20_POLY1305_128
: BCH_CSUM_CHACHA20_POLY1305_80;
return c->opts.data_checksum;
}
static inline unsigned bch2_meta_checksum_type(struct bch_fs *c)
{
return c->sb.encryption_type
? BCH_CSUM_CHACHA20_POLY1305_128
: c->opts.metadata_checksum;
}
static inline bool bch2_checksum_type_valid(const struct bch_fs *c,
unsigned type)
{
if (type >= BCH_CSUM_NR)
return false;
if (bch2_csum_type_is_encryption(type) && !c->chacha20)
return false;
return true;
}
static const unsigned bch_crc_bytes[] = {
[BCH_CSUM_NONE] = 0,
[BCH_CSUM_CRC32C] = 4,
[BCH_CSUM_CRC64] = 8,
[BCH_CSUM_CHACHA20_POLY1305_80] = 10,
[BCH_CSUM_CHACHA20_POLY1305_128] = 16,
};
static inline bool bch2_crc_cmp(struct bch_csum l, struct bch_csum r)
{
/*
* XXX: need some way of preventing the compiler from optimizing this
* into a form that isn't constant time..
*/
return ((l.lo ^ r.lo) | (l.hi ^ r.hi)) != 0;
}
/* for skipping ahead and encrypting/decrypting at an offset: */
static inline struct nonce nonce_add(struct nonce nonce, unsigned offset)
{
EBUG_ON(offset & (CHACHA20_BLOCK_SIZE - 1));
le32_add_cpu(&nonce.d[0], offset / CHACHA20_BLOCK_SIZE);
return nonce;
}
static inline bool bch2_key_is_encrypted(struct bch_encrypted_key *key)
{
return le64_to_cpu(key->magic) != BCH_KEY_MAGIC;
}
static inline struct nonce __bch2_sb_key_nonce(struct bch_sb *sb)
{
__le64 magic = __bch2_sb_magic(sb);
return (struct nonce) {{
[0] = 0,
[1] = 0,
[2] = ((__le32 *) &magic)[0],
[3] = ((__le32 *) &magic)[1],
}};
}
static inline struct nonce bch2_sb_key_nonce(struct bch_fs *c)
{
__le64 magic = bch2_sb_magic(c);
return (struct nonce) {{
[0] = 0,
[1] = 0,
[2] = ((__le32 *) &magic)[0],
[3] = ((__le32 *) &magic)[1],
}};
}
#endif /* _BCACHE_CHECKSUM_H */