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 void bch2_chacha20(const struct bch_key *, struct nonce, void *, size_t); 73 74 int bch2_request_key(struct bch_sb *, struct bch_key *); 75 #ifndef __KERNEL__ 76 int bch2_revoke_key(struct bch_sb *); 77 #endif 78 79 int bch2_encrypt(struct bch_fs *, unsigned, struct nonce, 80 void *data, size_t); 81 82 struct bch_csum bch2_checksum_bio(struct bch_fs *, unsigned, 83 struct nonce, struct bio *); 84 85 int bch2_rechecksum_bio(struct bch_fs *, struct bio *, struct bversion, 86 struct bch_extent_crc_unpacked, 87 struct bch_extent_crc_unpacked *, 88 struct bch_extent_crc_unpacked *, 89 unsigned, unsigned, unsigned); 90 91 int __bch2_encrypt_bio(struct bch_fs *, unsigned, 92 struct nonce, struct bio *); 93 94 static inline int bch2_encrypt_bio(struct bch_fs *c, unsigned type, 95 struct nonce nonce, struct bio *bio) 96 { 97 return bch2_csum_type_is_encryption(type) 98 ? __bch2_encrypt_bio(c, type, nonce, bio) 99 : 0; 100 } 101 102 extern const struct bch_sb_field_ops bch_sb_field_ops_crypt; 103 104 int bch2_decrypt_sb_key(struct bch_fs *, struct bch_sb_field_crypt *, 105 struct bch_key *); 106 107 #if 0 108 int bch2_disable_encryption(struct bch_fs *); 109 int bch2_enable_encryption(struct bch_fs *, bool); 110 #endif 111 112 void bch2_fs_encryption_exit(struct bch_fs *); 113 int bch2_fs_encryption_init(struct bch_fs *); 114 115 static inline enum bch_csum_type bch2_csum_opt_to_type(enum bch_csum_opt type, 116 bool data) 117 { 118 switch (type) { 119 case BCH_CSUM_OPT_none: 120 return BCH_CSUM_none; 121 case BCH_CSUM_OPT_crc32c: 122 return data ? BCH_CSUM_crc32c : BCH_CSUM_crc32c_nonzero; 123 case BCH_CSUM_OPT_crc64: 124 return data ? BCH_CSUM_crc64 : BCH_CSUM_crc64_nonzero; 125 case BCH_CSUM_OPT_xxhash: 126 return BCH_CSUM_xxhash; 127 default: 128 BUG(); 129 } 130 } 131 132 static inline enum bch_csum_type bch2_data_checksum_type(struct bch_fs *c, 133 struct bch_io_opts opts) 134 { 135 if (opts.nocow) 136 return 0; 137 138 if (c->sb.encryption_type) 139 return c->opts.wide_macs 140 ? BCH_CSUM_chacha20_poly1305_128 141 : BCH_CSUM_chacha20_poly1305_80; 142 143 return bch2_csum_opt_to_type(opts.data_checksum, true); 144 } 145 146 static inline enum bch_csum_type bch2_meta_checksum_type(struct bch_fs *c) 147 { 148 if (c->sb.encryption_type) 149 return BCH_CSUM_chacha20_poly1305_128; 150 151 return bch2_csum_opt_to_type(c->opts.metadata_checksum, false); 152 } 153 154 static inline bool bch2_checksum_type_valid(const struct bch_fs *c, 155 unsigned type) 156 { 157 if (type >= BCH_CSUM_NR) 158 return false; 159 160 if (bch2_csum_type_is_encryption(type) && !c->chacha20_key_set) 161 return false; 162 163 return true; 164 } 165 166 /* returns true if not equal */ 167 static inline bool bch2_crc_cmp(struct bch_csum l, struct bch_csum r) 168 { 169 /* 170 * XXX: need some way of preventing the compiler from optimizing this 171 * into a form that isn't constant time.. 172 */ 173 return ((l.lo ^ r.lo) | (l.hi ^ r.hi)) != 0; 174 } 175 176 /* for skipping ahead and encrypting/decrypting at an offset: */ 177 static inline struct nonce nonce_add(struct nonce nonce, unsigned offset) 178 { 179 EBUG_ON(offset & (CHACHA_BLOCK_SIZE - 1)); 180 181 le32_add_cpu(&nonce.d[0], offset / CHACHA_BLOCK_SIZE); 182 return nonce; 183 } 184 185 static inline struct nonce null_nonce(void) 186 { 187 struct nonce ret; 188 189 memset(&ret, 0, sizeof(ret)); 190 return ret; 191 } 192 193 static inline struct nonce extent_nonce(struct bversion version, 194 struct bch_extent_crc_unpacked crc) 195 { 196 unsigned compression_type = crc_is_compressed(crc) 197 ? crc.compression_type 198 : 0; 199 unsigned size = compression_type ? crc.uncompressed_size : 0; 200 struct nonce nonce = (struct nonce) {{ 201 [0] = cpu_to_le32(size << 22), 202 [1] = cpu_to_le32(version.lo), 203 [2] = cpu_to_le32(version.lo >> 32), 204 [3] = cpu_to_le32(version.hi| 205 (compression_type << 24))^BCH_NONCE_EXTENT, 206 }}; 207 208 return nonce_add(nonce, crc.nonce << 9); 209 } 210 211 static inline bool bch2_key_is_encrypted(struct bch_encrypted_key *key) 212 { 213 return le64_to_cpu(key->magic) != BCH_KEY_MAGIC; 214 } 215 216 static inline struct nonce __bch2_sb_key_nonce(struct bch_sb *sb) 217 { 218 __le64 magic = __bch2_sb_magic(sb); 219 220 return (struct nonce) {{ 221 [0] = 0, 222 [1] = 0, 223 [2] = ((__le32 *) &magic)[0], 224 [3] = ((__le32 *) &magic)[1], 225 }}; 226 } 227 228 static inline struct nonce bch2_sb_key_nonce(struct bch_fs *c) 229 { 230 __le64 magic = bch2_sb_magic(c); 231 232 return (struct nonce) {{ 233 [0] = 0, 234 [1] = 0, 235 [2] = ((__le32 *) &magic)[0], 236 [3] = ((__le32 *) &magic)[1], 237 }}; 238 } 239 240 #endif /* _BCACHEFS_CHECKSUM_H */ 241