1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _BCACHEFS_CHECKSUM_H 3 #define _BCACHEFS_CHECKSUM_H 4 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 12 static 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 25 struct 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 34 struct 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 structs 40 */ 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 48 static 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 59 static 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 72 int bch2_chacha_encrypt_key(struct bch_key *, struct nonce, void *, size_t); 73 int bch2_request_key(struct bch_sb *, struct bch_key *); 74 #ifndef __KERNEL__ 75 int bch2_revoke_key(struct bch_sb *); 76 #endif 77 78 int bch2_encrypt(struct bch_fs *, unsigned, struct nonce, 79 void *data, size_t); 80 81 struct bch_csum bch2_checksum_bio(struct bch_fs *, unsigned, 82 struct nonce, struct bio *); 83 84 int 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 90 int __bch2_encrypt_bio(struct bch_fs *, unsigned, 91 struct nonce, struct bio *); 92 93 static 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 } 100 101 extern const struct bch_sb_field_ops bch_sb_field_ops_crypt; 102 103 int bch2_decrypt_sb_key(struct bch_fs *, struct bch_sb_field_crypt *, 104 struct bch_key *); 105 106 int bch2_disable_encryption(struct bch_fs *); 107 int bch2_enable_encryption(struct bch_fs *, bool); 108 109 void bch2_fs_encryption_exit(struct bch_fs *); 110 int bch2_fs_encryption_init(struct bch_fs *); 111 112 static 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 } 128 129 static 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_macs 137 ? BCH_CSUM_chacha20_poly1305_128 138 : BCH_CSUM_chacha20_poly1305_80; 139 140 return bch2_csum_opt_to_type(opts.data_checksum, true); 141 } 142 143 static 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 } 150 151 static 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 */ 164 static 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 this 168 * 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: */ 174 static 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 } 181 182 static inline struct nonce null_nonce(void) 183 { 184 struct nonce ret; 185 186 memset(&ret, 0, sizeof(ret)); 187 return ret; 188 } 189 190 static 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_type 195 : 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 } 207 208 static inline bool bch2_key_is_encrypted(struct bch_encrypted_key *key) 209 { 210 return le64_to_cpu(key->magic) != BCH_KEY_MAGIC; 211 } 212 213 static 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 } 224 225 static 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