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_printf(out, "checksum error: got "); 65 bch2_csum_to_text(out, type, got); 66 prt_str(out, " should be "); 67 bch2_csum_to_text(out, type, expected); 68 prt_printf(out, " type %s", bch2_csum_types[type]); 69 } 70 71 int bch2_chacha_encrypt_key(struct bch_key *, struct nonce, void *, size_t); 72 int bch2_request_key(struct bch_sb *, struct bch_key *); 73 #ifndef __KERNEL__ 74 int bch2_revoke_key(struct bch_sb *); 75 #endif 76 77 int bch2_encrypt(struct bch_fs *, unsigned, struct nonce, 78 void *data, size_t); 79 80 struct bch_csum bch2_checksum_bio(struct bch_fs *, unsigned, 81 struct nonce, struct bio *); 82 83 int bch2_rechecksum_bio(struct bch_fs *, struct bio *, struct bversion, 84 struct bch_extent_crc_unpacked, 85 struct bch_extent_crc_unpacked *, 86 struct bch_extent_crc_unpacked *, 87 unsigned, unsigned, unsigned); 88 89 int __bch2_encrypt_bio(struct bch_fs *, unsigned, 90 struct nonce, struct bio *); 91 92 static inline int bch2_encrypt_bio(struct bch_fs *c, unsigned type, 93 struct nonce nonce, struct bio *bio) 94 { 95 return bch2_csum_type_is_encryption(type) 96 ? __bch2_encrypt_bio(c, type, nonce, bio) 97 : 0; 98 } 99 100 extern const struct bch_sb_field_ops bch_sb_field_ops_crypt; 101 102 int bch2_decrypt_sb_key(struct bch_fs *, struct bch_sb_field_crypt *, 103 struct bch_key *); 104 105 int bch2_disable_encryption(struct bch_fs *); 106 int bch2_enable_encryption(struct bch_fs *, bool); 107 108 void bch2_fs_encryption_exit(struct bch_fs *); 109 int bch2_fs_encryption_init(struct bch_fs *); 110 111 static inline enum bch_csum_type bch2_csum_opt_to_type(enum bch_csum_opts type, 112 bool data) 113 { 114 switch (type) { 115 case BCH_CSUM_OPT_none: 116 return BCH_CSUM_none; 117 case BCH_CSUM_OPT_crc32c: 118 return data ? BCH_CSUM_crc32c : BCH_CSUM_crc32c_nonzero; 119 case BCH_CSUM_OPT_crc64: 120 return data ? BCH_CSUM_crc64 : BCH_CSUM_crc64_nonzero; 121 case BCH_CSUM_OPT_xxhash: 122 return BCH_CSUM_xxhash; 123 default: 124 BUG(); 125 } 126 } 127 128 static inline enum bch_csum_type bch2_data_checksum_type(struct bch_fs *c, 129 struct bch_io_opts opts) 130 { 131 if (opts.nocow) 132 return 0; 133 134 if (c->sb.encryption_type) 135 return c->opts.wide_macs 136 ? BCH_CSUM_chacha20_poly1305_128 137 : BCH_CSUM_chacha20_poly1305_80; 138 139 return bch2_csum_opt_to_type(opts.data_checksum, true); 140 } 141 142 static inline enum bch_csum_type bch2_meta_checksum_type(struct bch_fs *c) 143 { 144 if (c->sb.encryption_type) 145 return BCH_CSUM_chacha20_poly1305_128; 146 147 return bch2_csum_opt_to_type(c->opts.metadata_checksum, false); 148 } 149 150 static inline bool bch2_checksum_type_valid(const struct bch_fs *c, 151 unsigned type) 152 { 153 if (type >= BCH_CSUM_NR) 154 return false; 155 156 if (bch2_csum_type_is_encryption(type) && !c->chacha20) 157 return false; 158 159 return true; 160 } 161 162 /* returns true if not equal */ 163 static inline bool bch2_crc_cmp(struct bch_csum l, struct bch_csum r) 164 { 165 /* 166 * XXX: need some way of preventing the compiler from optimizing this 167 * into a form that isn't constant time.. 168 */ 169 return ((l.lo ^ r.lo) | (l.hi ^ r.hi)) != 0; 170 } 171 172 /* for skipping ahead and encrypting/decrypting at an offset: */ 173 static inline struct nonce nonce_add(struct nonce nonce, unsigned offset) 174 { 175 EBUG_ON(offset & (CHACHA_BLOCK_SIZE - 1)); 176 177 le32_add_cpu(&nonce.d[0], offset / CHACHA_BLOCK_SIZE); 178 return nonce; 179 } 180 181 static inline struct nonce null_nonce(void) 182 { 183 struct nonce ret; 184 185 memset(&ret, 0, sizeof(ret)); 186 return ret; 187 } 188 189 static inline struct nonce extent_nonce(struct bversion version, 190 struct bch_extent_crc_unpacked crc) 191 { 192 unsigned compression_type = crc_is_compressed(crc) 193 ? crc.compression_type 194 : 0; 195 unsigned size = compression_type ? crc.uncompressed_size : 0; 196 struct nonce nonce = (struct nonce) {{ 197 [0] = cpu_to_le32(size << 22), 198 [1] = cpu_to_le32(version.lo), 199 [2] = cpu_to_le32(version.lo >> 32), 200 [3] = cpu_to_le32(version.hi| 201 (compression_type << 24))^BCH_NONCE_EXTENT, 202 }}; 203 204 return nonce_add(nonce, crc.nonce << 9); 205 } 206 207 static inline bool bch2_key_is_encrypted(struct bch_encrypted_key *key) 208 { 209 return le64_to_cpu(key->magic) != BCH_KEY_MAGIC; 210 } 211 212 static inline struct nonce __bch2_sb_key_nonce(struct bch_sb *sb) 213 { 214 __le64 magic = __bch2_sb_magic(sb); 215 216 return (struct nonce) {{ 217 [0] = 0, 218 [1] = 0, 219 [2] = ((__le32 *) &magic)[0], 220 [3] = ((__le32 *) &magic)[1], 221 }}; 222 } 223 224 static inline struct nonce bch2_sb_key_nonce(struct bch_fs *c) 225 { 226 __le64 magic = bch2_sb_magic(c); 227 228 return (struct nonce) {{ 229 [0] = 0, 230 [1] = 0, 231 [2] = ((__le32 *) &magic)[0], 232 [3] = ((__le32 *) &magic)[1], 233 }}; 234 } 235 236 #endif /* _BCACHEFS_CHECKSUM_H */ 237