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
bch2_checksum_mergeable(unsigned type)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
bch2_csum_to_text(struct printbuf * out,enum bch_csum_type type,struct bch_csum csum)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
bch2_csum_err_msg(struct printbuf * out,enum bch_csum_type type,struct bch_csum expected,struct bch_csum got)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
bch2_encrypt_bio(struct bch_fs * c,unsigned type,struct nonce nonce,struct bio * bio)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 #if 0
107 int bch2_disable_encryption(struct bch_fs *);
108 int bch2_enable_encryption(struct bch_fs *, bool);
109 #endif
110
111 void bch2_fs_encryption_exit(struct bch_fs *);
112 int bch2_fs_encryption_init(struct bch_fs *);
113
bch2_csum_opt_to_type(enum bch_csum_opt type,bool data)114 static inline enum bch_csum_type bch2_csum_opt_to_type(enum bch_csum_opt type,
115 bool data)
116 {
117 switch (type) {
118 case BCH_CSUM_OPT_none:
119 return BCH_CSUM_none;
120 case BCH_CSUM_OPT_crc32c:
121 return data ? BCH_CSUM_crc32c : BCH_CSUM_crc32c_nonzero;
122 case BCH_CSUM_OPT_crc64:
123 return data ? BCH_CSUM_crc64 : BCH_CSUM_crc64_nonzero;
124 case BCH_CSUM_OPT_xxhash:
125 return BCH_CSUM_xxhash;
126 default:
127 BUG();
128 }
129 }
130
bch2_data_checksum_type(struct bch_fs * c,struct bch_io_opts opts)131 static inline enum bch_csum_type bch2_data_checksum_type(struct bch_fs *c,
132 struct bch_io_opts opts)
133 {
134 if (opts.nocow)
135 return 0;
136
137 if (c->sb.encryption_type)
138 return c->opts.wide_macs
139 ? BCH_CSUM_chacha20_poly1305_128
140 : BCH_CSUM_chacha20_poly1305_80;
141
142 return bch2_csum_opt_to_type(opts.data_checksum, true);
143 }
144
bch2_meta_checksum_type(struct bch_fs * c)145 static inline enum bch_csum_type bch2_meta_checksum_type(struct bch_fs *c)
146 {
147 if (c->sb.encryption_type)
148 return BCH_CSUM_chacha20_poly1305_128;
149
150 return bch2_csum_opt_to_type(c->opts.metadata_checksum, false);
151 }
152
bch2_checksum_type_valid(const struct bch_fs * c,unsigned type)153 static inline bool bch2_checksum_type_valid(const struct bch_fs *c,
154 unsigned type)
155 {
156 if (type >= BCH_CSUM_NR)
157 return false;
158
159 if (bch2_csum_type_is_encryption(type) && !c->chacha20)
160 return false;
161
162 return true;
163 }
164
165 /* returns true if not equal */
bch2_crc_cmp(struct bch_csum l,struct bch_csum r)166 static inline bool bch2_crc_cmp(struct bch_csum l, struct bch_csum r)
167 {
168 /*
169 * XXX: need some way of preventing the compiler from optimizing this
170 * into a form that isn't constant time..
171 */
172 return ((l.lo ^ r.lo) | (l.hi ^ r.hi)) != 0;
173 }
174
175 /* for skipping ahead and encrypting/decrypting at an offset: */
nonce_add(struct nonce nonce,unsigned offset)176 static inline struct nonce nonce_add(struct nonce nonce, unsigned offset)
177 {
178 EBUG_ON(offset & (CHACHA_BLOCK_SIZE - 1));
179
180 le32_add_cpu(&nonce.d[0], offset / CHACHA_BLOCK_SIZE);
181 return nonce;
182 }
183
null_nonce(void)184 static inline struct nonce null_nonce(void)
185 {
186 struct nonce ret;
187
188 memset(&ret, 0, sizeof(ret));
189 return ret;
190 }
191
extent_nonce(struct bversion version,struct bch_extent_crc_unpacked crc)192 static inline struct nonce extent_nonce(struct bversion version,
193 struct bch_extent_crc_unpacked crc)
194 {
195 unsigned compression_type = crc_is_compressed(crc)
196 ? crc.compression_type
197 : 0;
198 unsigned size = compression_type ? crc.uncompressed_size : 0;
199 struct nonce nonce = (struct nonce) {{
200 [0] = cpu_to_le32(size << 22),
201 [1] = cpu_to_le32(version.lo),
202 [2] = cpu_to_le32(version.lo >> 32),
203 [3] = cpu_to_le32(version.hi|
204 (compression_type << 24))^BCH_NONCE_EXTENT,
205 }};
206
207 return nonce_add(nonce, crc.nonce << 9);
208 }
209
bch2_key_is_encrypted(struct bch_encrypted_key * key)210 static inline bool bch2_key_is_encrypted(struct bch_encrypted_key *key)
211 {
212 return le64_to_cpu(key->magic) != BCH_KEY_MAGIC;
213 }
214
__bch2_sb_key_nonce(struct bch_sb * sb)215 static inline struct nonce __bch2_sb_key_nonce(struct bch_sb *sb)
216 {
217 __le64 magic = __bch2_sb_magic(sb);
218
219 return (struct nonce) {{
220 [0] = 0,
221 [1] = 0,
222 [2] = ((__le32 *) &magic)[0],
223 [3] = ((__le32 *) &magic)[1],
224 }};
225 }
226
bch2_sb_key_nonce(struct bch_fs * c)227 static inline struct nonce bch2_sb_key_nonce(struct bch_fs *c)
228 {
229 __le64 magic = bch2_sb_magic(c);
230
231 return (struct nonce) {{
232 [0] = 0,
233 [1] = 0,
234 [2] = ((__le32 *) &magic)[0],
235 [3] = ((__le32 *) &magic)[1],
236 }};
237 }
238
239 #endif /* _BCACHEFS_CHECKSUM_H */
240