linux/fs/bcachefs/checksum.h
Kent Overstreet 4819b66e29 bcachefs: improve checksum error messages
new helpers:
 - bch2_csum_to_text()
 - bch2_csum_err_msg()

standardize our checksum error messages a bit, and print out the
checksums a bit more nicely.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-05 23:24:21 -05:00

237 lines
5.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _BCACHEFS_CHECKSUM_H
#define _BCACHEFS_CHECKSUM_H
#include "bcachefs.h"
#include "extents_types.h"
#include "super-io.h"
#include <linux/crc64.h>
#include <crypto/chacha.h>
static inline bool bch2_checksum_mergeable(unsigned type)
{
switch (type) {
case BCH_CSUM_none:
case BCH_CSUM_crc32c:
case BCH_CSUM_crc64:
return true;
default:
return false;
}
}
struct bch_csum bch2_checksum_merge(unsigned, struct bch_csum,
struct bch_csum, 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);\
\
bch2_checksum(_c, _type, _nonce, _start, vstruct_end(_i) - _start);\
})
static inline void bch2_csum_to_text(struct printbuf *out,
enum bch_csum_type type,
struct bch_csum csum)
{
const u8 *p = (u8 *) &csum;
unsigned bytes = type < BCH_CSUM_NR ? bch_crc_bytes[type] : 16;
for (unsigned i = 0; i < bytes; i++)
prt_hex_byte(out, p[i]);
}
static inline void bch2_csum_err_msg(struct printbuf *out,
enum bch_csum_type type,
struct bch_csum expected,
struct bch_csum got)
{
prt_printf(out, "checksum error: got ");
bch2_csum_to_text(out, type, got);
prt_str(out, " should be ");
bch2_csum_to_text(out, type, expected);
prt_printf(out, " type %s", bch2_csum_types[type]);
}
int bch2_chacha_encrypt_key(struct bch_key *, struct nonce, void *, size_t);
int bch2_request_key(struct bch_sb *, struct bch_key *);
#ifndef __KERNEL__
int bch2_revoke_key(struct bch_sb *);
#endif
int 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 *);
int bch2_rechecksum_bio(struct bch_fs *, struct bio *, struct bversion,
struct bch_extent_crc_unpacked,
struct bch_extent_crc_unpacked *,
struct bch_extent_crc_unpacked *,
unsigned, unsigned, unsigned);
int __bch2_encrypt_bio(struct bch_fs *, unsigned,
struct nonce, struct bio *);
static inline int bch2_encrypt_bio(struct bch_fs *c, unsigned type,
struct nonce nonce, struct bio *bio)
{
return bch2_csum_type_is_encryption(type)
? __bch2_encrypt_bio(c, type, nonce, bio)
: 0;
}
extern const struct bch_sb_field_ops bch_sb_field_ops_crypt;
int bch2_decrypt_sb_key(struct bch_fs *, struct bch_sb_field_crypt *,
struct bch_key *);
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 enum bch_csum_type bch2_csum_opt_to_type(enum bch_csum_opts type,
bool data)
{
switch (type) {
case BCH_CSUM_OPT_none:
return BCH_CSUM_none;
case BCH_CSUM_OPT_crc32c:
return data ? BCH_CSUM_crc32c : BCH_CSUM_crc32c_nonzero;
case BCH_CSUM_OPT_crc64:
return data ? BCH_CSUM_crc64 : BCH_CSUM_crc64_nonzero;
case BCH_CSUM_OPT_xxhash:
return BCH_CSUM_xxhash;
default:
BUG();
}
}
static inline enum bch_csum_type bch2_data_checksum_type(struct bch_fs *c,
struct bch_io_opts opts)
{
if (opts.nocow)
return 0;
if (c->sb.encryption_type)
return c->opts.wide_macs
? BCH_CSUM_chacha20_poly1305_128
: BCH_CSUM_chacha20_poly1305_80;
return bch2_csum_opt_to_type(opts.data_checksum, true);
}
static inline enum bch_csum_type bch2_meta_checksum_type(struct bch_fs *c)
{
if (c->sb.encryption_type)
return BCH_CSUM_chacha20_poly1305_128;
return bch2_csum_opt_to_type(c->opts.metadata_checksum, false);
}
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;
}
/* returns true if not equal */
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 & (CHACHA_BLOCK_SIZE - 1));
le32_add_cpu(&nonce.d[0], offset / CHACHA_BLOCK_SIZE);
return nonce;
}
static inline struct nonce null_nonce(void)
{
struct nonce ret;
memset(&ret, 0, sizeof(ret));
return ret;
}
static inline struct nonce extent_nonce(struct bversion version,
struct bch_extent_crc_unpacked crc)
{
unsigned compression_type = crc_is_compressed(crc)
? crc.compression_type
: 0;
unsigned size = compression_type ? crc.uncompressed_size : 0;
struct nonce nonce = (struct nonce) {{
[0] = cpu_to_le32(size << 22),
[1] = cpu_to_le32(version.lo),
[2] = cpu_to_le32(version.lo >> 32),
[3] = cpu_to_le32(version.hi|
(compression_type << 24))^BCH_NONCE_EXTENT,
}};
return nonce_add(nonce, crc.nonce << 9);
}
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 /* _BCACHEFS_CHECKSUM_H */