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, byte: 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, str: "checksum error, type " ); |
65 | bch2_prt_csum_type(out, type); |
66 | prt_str(out, str: ": got " ); |
67 | bch2_csum_to_text(out, type, csum: got); |
68 | prt_str(out, str: " should be " ); |
69 | bch2_csum_to_text(out, type, csum: 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(type: opts.data_checksum, data: 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(type: c->opts.metadata_checksum, data: 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(var: &nonce.d[0], val: 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, offset: 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 | |