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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef _BCACHEFS_CHECKSUM_H3#define _BCACHEFS_CHECKSUM_H4 5#include "bcachefs.h"6#include "extents_types.h"7#include "super-io.h"8 9#include <linux/crc64.h>10#include <crypto/chacha.h>11 12static inline bool bch2_checksum_mergeable(unsigned type)13{14 15 switch (type) {16 case BCH_CSUM_none:17 case BCH_CSUM_crc32c:18 case BCH_CSUM_crc64:19 return true;20 default:21 return false;22 }23}24 25struct bch_csum bch2_checksum_merge(unsigned, struct bch_csum,26 struct bch_csum, size_t);27 28#define BCH_NONCE_EXTENT cpu_to_le32(1 << 28)29#define BCH_NONCE_BTREE cpu_to_le32(2 << 28)30#define BCH_NONCE_JOURNAL cpu_to_le32(3 << 28)31#define BCH_NONCE_PRIO cpu_to_le32(4 << 28)32#define BCH_NONCE_POLY cpu_to_le32(1 << 31)33 34struct bch_csum bch2_checksum(struct bch_fs *, unsigned, struct nonce,35 const void *, size_t);36 37/*38 * This is used for various on disk data structures - bch_sb, prio_set, bset,39 * jset: The checksum is _always_ the first field of these structs40 */41#define csum_vstruct(_c, _type, _nonce, _i) \42({ \43 const void *_start = ((const void *) (_i)) + sizeof((_i)->csum);\44 \45 bch2_checksum(_c, _type, _nonce, _start, vstruct_end(_i) - _start);\46})47 48static inline void bch2_csum_to_text(struct printbuf *out,49 enum bch_csum_type type,50 struct bch_csum csum)51{52 const u8 *p = (u8 *) &csum;53 unsigned bytes = type < BCH_CSUM_NR ? bch_crc_bytes[type] : 16;54 55 for (unsigned i = 0; i < bytes; i++)56 prt_hex_byte(out, p[i]);57}58 59static inline void bch2_csum_err_msg(struct printbuf *out,60 enum bch_csum_type type,61 struct bch_csum expected,62 struct bch_csum got)63{64 prt_str(out, "checksum error, type ");65 bch2_prt_csum_type(out, type);66 prt_str(out, ": got ");67 bch2_csum_to_text(out, type, got);68 prt_str(out, " should be ");69 bch2_csum_to_text(out, type, expected);70}71 72int bch2_chacha_encrypt_key(struct bch_key *, struct nonce, void *, size_t);73int bch2_request_key(struct bch_sb *, struct bch_key *);74#ifndef __KERNEL__75int bch2_revoke_key(struct bch_sb *);76#endif77 78int bch2_encrypt(struct bch_fs *, unsigned, struct nonce,79 void *data, size_t);80 81struct bch_csum bch2_checksum_bio(struct bch_fs *, unsigned,82 struct nonce, struct bio *);83 84int bch2_rechecksum_bio(struct bch_fs *, struct bio *, struct bversion,85 struct bch_extent_crc_unpacked,86 struct bch_extent_crc_unpacked *,87 struct bch_extent_crc_unpacked *,88 unsigned, unsigned, unsigned);89 90int __bch2_encrypt_bio(struct bch_fs *, unsigned,91 struct nonce, struct bio *);92 93static inline int bch2_encrypt_bio(struct bch_fs *c, unsigned type,94 struct nonce nonce, struct bio *bio)95{96 return bch2_csum_type_is_encryption(type)97 ? __bch2_encrypt_bio(c, type, nonce, bio)98 : 0;99}100 101extern const struct bch_sb_field_ops bch_sb_field_ops_crypt;102 103int bch2_decrypt_sb_key(struct bch_fs *, struct bch_sb_field_crypt *,104 struct bch_key *);105 106int bch2_disable_encryption(struct bch_fs *);107int bch2_enable_encryption(struct bch_fs *, bool);108 109void bch2_fs_encryption_exit(struct bch_fs *);110int bch2_fs_encryption_init(struct bch_fs *);111 112static inline enum bch_csum_type bch2_csum_opt_to_type(enum bch_csum_opts type,113 bool data)114{115 switch (type) {116 case BCH_CSUM_OPT_none:117 return BCH_CSUM_none;118 case BCH_CSUM_OPT_crc32c:119 return data ? BCH_CSUM_crc32c : BCH_CSUM_crc32c_nonzero;120 case BCH_CSUM_OPT_crc64:121 return data ? BCH_CSUM_crc64 : BCH_CSUM_crc64_nonzero;122 case BCH_CSUM_OPT_xxhash:123 return BCH_CSUM_xxhash;124 default:125 BUG();126 }127}128 129static inline enum bch_csum_type bch2_data_checksum_type(struct bch_fs *c,130 struct bch_io_opts opts)131{132 if (opts.nocow)133 return 0;134 135 if (c->sb.encryption_type)136 return c->opts.wide_macs137 ? BCH_CSUM_chacha20_poly1305_128138 : BCH_CSUM_chacha20_poly1305_80;139 140 return bch2_csum_opt_to_type(opts.data_checksum, true);141}142 143static inline enum bch_csum_type bch2_meta_checksum_type(struct bch_fs *c)144{145 if (c->sb.encryption_type)146 return BCH_CSUM_chacha20_poly1305_128;147 148 return bch2_csum_opt_to_type(c->opts.metadata_checksum, false);149}150 151static inline bool bch2_checksum_type_valid(const struct bch_fs *c,152 unsigned type)153{154 if (type >= BCH_CSUM_NR)155 return false;156 157 if (bch2_csum_type_is_encryption(type) && !c->chacha20)158 return false;159 160 return true;161}162 163/* returns true if not equal */164static inline bool bch2_crc_cmp(struct bch_csum l, struct bch_csum r)165{166 /*167 * XXX: need some way of preventing the compiler from optimizing this168 * into a form that isn't constant time..169 */170 return ((l.lo ^ r.lo) | (l.hi ^ r.hi)) != 0;171}172 173/* for skipping ahead and encrypting/decrypting at an offset: */174static inline struct nonce nonce_add(struct nonce nonce, unsigned offset)175{176 EBUG_ON(offset & (CHACHA_BLOCK_SIZE - 1));177 178 le32_add_cpu(&nonce.d[0], offset / CHACHA_BLOCK_SIZE);179 return nonce;180}181 182static inline struct nonce null_nonce(void)183{184 struct nonce ret;185 186 memset(&ret, 0, sizeof(ret));187 return ret;188}189 190static inline struct nonce extent_nonce(struct bversion version,191 struct bch_extent_crc_unpacked crc)192{193 unsigned compression_type = crc_is_compressed(crc)194 ? crc.compression_type195 : 0;196 unsigned size = compression_type ? crc.uncompressed_size : 0;197 struct nonce nonce = (struct nonce) {{198 [0] = cpu_to_le32(size << 22),199 [1] = cpu_to_le32(version.lo),200 [2] = cpu_to_le32(version.lo >> 32),201 [3] = cpu_to_le32(version.hi|202 (compression_type << 24))^BCH_NONCE_EXTENT,203 }};204 205 return nonce_add(nonce, crc.nonce << 9);206}207 208static inline bool bch2_key_is_encrypted(struct bch_encrypted_key *key)209{210 return le64_to_cpu(key->magic) != BCH_KEY_MAGIC;211}212 213static inline struct nonce __bch2_sb_key_nonce(struct bch_sb *sb)214{215 __le64 magic = __bch2_sb_magic(sb);216 217 return (struct nonce) {{218 [0] = 0,219 [1] = 0,220 [2] = ((__le32 *) &magic)[0],221 [3] = ((__le32 *) &magic)[1],222 }};223}224 225static inline struct nonce bch2_sb_key_nonce(struct bch_fs *c)226{227 __le64 magic = bch2_sb_magic(c);228 229 return (struct nonce) {{230 [0] = 0,231 [1] = 0,232 [2] = ((__le32 *) &magic)[0],233 [3] = ((__le32 *) &magic)[1],234 }};235}236 237#endif /* _BCACHEFS_CHECKSUM_H */238