1 // SPDX-License-Identifier: GPL-2.0 1 // SPDX-License-Identifier: GPL-2.0
2 /* 2 /*
3 * Copyright 2019 Google LLC 3 * Copyright 2019 Google LLC
4 */ 4 */
5 5
6 /* 6 /*
7 * Refer to Documentation/block/inline-encrypt 7 * Refer to Documentation/block/inline-encryption.rst for detailed explanation.
8 */ 8 */
9 9
10 #define pr_fmt(fmt) "blk-crypto: " fmt 10 #define pr_fmt(fmt) "blk-crypto: " fmt
11 11
12 #include <linux/bio.h> 12 #include <linux/bio.h>
13 #include <linux/blkdev.h> 13 #include <linux/blkdev.h>
14 #include <linux/blk-crypto-profile.h> 14 #include <linux/blk-crypto-profile.h>
15 #include <linux/module.h> 15 #include <linux/module.h>
16 #include <linux/ratelimit.h> 16 #include <linux/ratelimit.h>
17 #include <linux/slab.h> 17 #include <linux/slab.h>
18 18
19 #include "blk-crypto-internal.h" 19 #include "blk-crypto-internal.h"
20 20
21 const struct blk_crypto_mode blk_crypto_modes[ 21 const struct blk_crypto_mode blk_crypto_modes[] = {
22 [BLK_ENCRYPTION_MODE_AES_256_XTS] = { 22 [BLK_ENCRYPTION_MODE_AES_256_XTS] = {
23 .name = "AES-256-XTS", 23 .name = "AES-256-XTS",
24 .cipher_str = "xts(aes)", 24 .cipher_str = "xts(aes)",
25 .keysize = 64, 25 .keysize = 64,
26 .ivsize = 16, 26 .ivsize = 16,
27 }, 27 },
28 [BLK_ENCRYPTION_MODE_AES_128_CBC_ESSIV 28 [BLK_ENCRYPTION_MODE_AES_128_CBC_ESSIV] = {
29 .name = "AES-128-CBC-ESSIV", 29 .name = "AES-128-CBC-ESSIV",
30 .cipher_str = "essiv(cbc(aes), 30 .cipher_str = "essiv(cbc(aes),sha256)",
31 .keysize = 16, 31 .keysize = 16,
32 .ivsize = 16, 32 .ivsize = 16,
33 }, 33 },
34 [BLK_ENCRYPTION_MODE_ADIANTUM] = { 34 [BLK_ENCRYPTION_MODE_ADIANTUM] = {
35 .name = "Adiantum", 35 .name = "Adiantum",
36 .cipher_str = "adiantum(xchach 36 .cipher_str = "adiantum(xchacha12,aes)",
37 .keysize = 32, 37 .keysize = 32,
38 .ivsize = 32, 38 .ivsize = 32,
39 }, 39 },
40 [BLK_ENCRYPTION_MODE_SM4_XTS] = { 40 [BLK_ENCRYPTION_MODE_SM4_XTS] = {
41 .name = "SM4-XTS", 41 .name = "SM4-XTS",
42 .cipher_str = "xts(sm4)", 42 .cipher_str = "xts(sm4)",
43 .keysize = 32, 43 .keysize = 32,
44 .ivsize = 16, 44 .ivsize = 16,
45 }, 45 },
46 }; 46 };
47 47
48 /* 48 /*
49 * This number needs to be at least (the numbe 49 * This number needs to be at least (the number of threads doing IO
50 * concurrently) * (maximum recursive depth of 50 * concurrently) * (maximum recursive depth of a bio), so that we don't
51 * deadlock on crypt_ctx allocations. The defa 51 * deadlock on crypt_ctx allocations. The default is chosen to be the same
52 * as the default number of post read contexts 52 * as the default number of post read contexts in both EXT4 and F2FS.
53 */ 53 */
54 static int num_prealloc_crypt_ctxs = 128; 54 static int num_prealloc_crypt_ctxs = 128;
55 55
56 module_param(num_prealloc_crypt_ctxs, int, 044 56 module_param(num_prealloc_crypt_ctxs, int, 0444);
57 MODULE_PARM_DESC(num_prealloc_crypt_ctxs, 57 MODULE_PARM_DESC(num_prealloc_crypt_ctxs,
58 "Number of bio crypto contexts 58 "Number of bio crypto contexts to preallocate");
59 59
60 static struct kmem_cache *bio_crypt_ctx_cache; 60 static struct kmem_cache *bio_crypt_ctx_cache;
61 static mempool_t *bio_crypt_ctx_pool; 61 static mempool_t *bio_crypt_ctx_pool;
62 62
63 static int __init bio_crypt_ctx_init(void) 63 static int __init bio_crypt_ctx_init(void)
64 { 64 {
65 size_t i; 65 size_t i;
66 66
67 bio_crypt_ctx_cache = KMEM_CACHE(bio_c 67 bio_crypt_ctx_cache = KMEM_CACHE(bio_crypt_ctx, 0);
68 if (!bio_crypt_ctx_cache) 68 if (!bio_crypt_ctx_cache)
69 goto out_no_mem; 69 goto out_no_mem;
70 70
71 bio_crypt_ctx_pool = mempool_create_sl 71 bio_crypt_ctx_pool = mempool_create_slab_pool(num_prealloc_crypt_ctxs,
72 72 bio_crypt_ctx_cache);
73 if (!bio_crypt_ctx_pool) 73 if (!bio_crypt_ctx_pool)
74 goto out_no_mem; 74 goto out_no_mem;
75 75
76 /* This is assumed in various places. 76 /* This is assumed in various places. */
77 BUILD_BUG_ON(BLK_ENCRYPTION_MODE_INVAL 77 BUILD_BUG_ON(BLK_ENCRYPTION_MODE_INVALID != 0);
78 78
79 /* Sanity check that no algorithm exce 79 /* Sanity check that no algorithm exceeds the defined limits. */
80 for (i = 0; i < BLK_ENCRYPTION_MODE_MA 80 for (i = 0; i < BLK_ENCRYPTION_MODE_MAX; i++) {
81 BUG_ON(blk_crypto_modes[i].key 81 BUG_ON(blk_crypto_modes[i].keysize > BLK_CRYPTO_MAX_KEY_SIZE);
82 BUG_ON(blk_crypto_modes[i].ivs 82 BUG_ON(blk_crypto_modes[i].ivsize > BLK_CRYPTO_MAX_IV_SIZE);
83 } 83 }
84 84
85 return 0; 85 return 0;
86 out_no_mem: 86 out_no_mem:
87 panic("Failed to allocate mem for bio 87 panic("Failed to allocate mem for bio crypt ctxs\n");
88 } 88 }
89 subsys_initcall(bio_crypt_ctx_init); 89 subsys_initcall(bio_crypt_ctx_init);
90 90
91 void bio_crypt_set_ctx(struct bio *bio, const 91 void bio_crypt_set_ctx(struct bio *bio, const struct blk_crypto_key *key,
92 const u64 dun[BLK_CRYPT 92 const u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE], gfp_t gfp_mask)
93 { 93 {
94 struct bio_crypt_ctx *bc; 94 struct bio_crypt_ctx *bc;
95 95
96 /* 96 /*
97 * The caller must use a gfp_mask that 97 * The caller must use a gfp_mask that contains __GFP_DIRECT_RECLAIM so
98 * that the mempool_alloc() can't fail 98 * that the mempool_alloc() can't fail.
99 */ 99 */
100 WARN_ON_ONCE(!(gfp_mask & __GFP_DIRECT 100 WARN_ON_ONCE(!(gfp_mask & __GFP_DIRECT_RECLAIM));
101 101
102 bc = mempool_alloc(bio_crypt_ctx_pool, 102 bc = mempool_alloc(bio_crypt_ctx_pool, gfp_mask);
103 103
104 bc->bc_key = key; 104 bc->bc_key = key;
105 memcpy(bc->bc_dun, dun, sizeof(bc->bc_ 105 memcpy(bc->bc_dun, dun, sizeof(bc->bc_dun));
106 106
107 bio->bi_crypt_context = bc; 107 bio->bi_crypt_context = bc;
108 } 108 }
109 109
110 void __bio_crypt_free_ctx(struct bio *bio) 110 void __bio_crypt_free_ctx(struct bio *bio)
111 { 111 {
112 mempool_free(bio->bi_crypt_context, bi 112 mempool_free(bio->bi_crypt_context, bio_crypt_ctx_pool);
113 bio->bi_crypt_context = NULL; 113 bio->bi_crypt_context = NULL;
114 } 114 }
115 115
116 int __bio_crypt_clone(struct bio *dst, struct 116 int __bio_crypt_clone(struct bio *dst, struct bio *src, gfp_t gfp_mask)
117 { 117 {
118 dst->bi_crypt_context = mempool_alloc( 118 dst->bi_crypt_context = mempool_alloc(bio_crypt_ctx_pool, gfp_mask);
119 if (!dst->bi_crypt_context) 119 if (!dst->bi_crypt_context)
120 return -ENOMEM; 120 return -ENOMEM;
121 *dst->bi_crypt_context = *src->bi_cryp 121 *dst->bi_crypt_context = *src->bi_crypt_context;
122 return 0; 122 return 0;
123 } 123 }
124 124
125 /* Increments @dun by @inc, treating @dun as a 125 /* Increments @dun by @inc, treating @dun as a multi-limb integer. */
126 void bio_crypt_dun_increment(u64 dun[BLK_CRYPT 126 void bio_crypt_dun_increment(u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE],
127 unsigned int inc) 127 unsigned int inc)
128 { 128 {
129 int i; 129 int i;
130 130
131 for (i = 0; inc && i < BLK_CRYPTO_DUN_ 131 for (i = 0; inc && i < BLK_CRYPTO_DUN_ARRAY_SIZE; i++) {
132 dun[i] += inc; 132 dun[i] += inc;
133 /* 133 /*
134 * If the addition in this lim 134 * If the addition in this limb overflowed, then we need to
135 * carry 1 into the next limb. 135 * carry 1 into the next limb. Else the carry is 0.
136 */ 136 */
137 if (dun[i] < inc) 137 if (dun[i] < inc)
138 inc = 1; 138 inc = 1;
139 else 139 else
140 inc = 0; 140 inc = 0;
141 } 141 }
142 } 142 }
143 143
144 void __bio_crypt_advance(struct bio *bio, unsi 144 void __bio_crypt_advance(struct bio *bio, unsigned int bytes)
145 { 145 {
146 struct bio_crypt_ctx *bc = bio->bi_cry 146 struct bio_crypt_ctx *bc = bio->bi_crypt_context;
147 147
148 bio_crypt_dun_increment(bc->bc_dun, 148 bio_crypt_dun_increment(bc->bc_dun,
149 bytes >> bc->b 149 bytes >> bc->bc_key->data_unit_size_bits);
150 } 150 }
151 151
152 /* 152 /*
153 * Returns true if @bc->bc_dun plus @bytes con 153 * Returns true if @bc->bc_dun plus @bytes converted to data units is equal to
154 * @next_dun, treating the DUNs as multi-limb 154 * @next_dun, treating the DUNs as multi-limb integers.
155 */ 155 */
156 bool bio_crypt_dun_is_contiguous(const struct 156 bool bio_crypt_dun_is_contiguous(const struct bio_crypt_ctx *bc,
157 unsigned int 157 unsigned int bytes,
158 const u64 nex 158 const u64 next_dun[BLK_CRYPTO_DUN_ARRAY_SIZE])
159 { 159 {
160 int i; 160 int i;
161 unsigned int carry = bytes >> bc->bc_k 161 unsigned int carry = bytes >> bc->bc_key->data_unit_size_bits;
162 162
163 for (i = 0; i < BLK_CRYPTO_DUN_ARRAY_S 163 for (i = 0; i < BLK_CRYPTO_DUN_ARRAY_SIZE; i++) {
164 if (bc->bc_dun[i] + carry != n 164 if (bc->bc_dun[i] + carry != next_dun[i])
165 return false; 165 return false;
166 /* 166 /*
167 * If the addition in this lim 167 * If the addition in this limb overflowed, then we need to
168 * carry 1 into the next limb. 168 * carry 1 into the next limb. Else the carry is 0.
169 */ 169 */
170 if ((bc->bc_dun[i] + carry) < 170 if ((bc->bc_dun[i] + carry) < carry)
171 carry = 1; 171 carry = 1;
172 else 172 else
173 carry = 0; 173 carry = 0;
174 } 174 }
175 175
176 /* If the DUN wrapped through 0, don't 176 /* If the DUN wrapped through 0, don't treat it as contiguous. */
177 return carry == 0; 177 return carry == 0;
178 } 178 }
179 179
180 /* 180 /*
181 * Checks that two bio crypt contexts are comp 181 * Checks that two bio crypt contexts are compatible - i.e. that
182 * they are mergeable except for data_unit_num 182 * they are mergeable except for data_unit_num continuity.
183 */ 183 */
184 static bool bio_crypt_ctx_compatible(struct bi 184 static bool bio_crypt_ctx_compatible(struct bio_crypt_ctx *bc1,
185 struct bi 185 struct bio_crypt_ctx *bc2)
186 { 186 {
187 if (!bc1) 187 if (!bc1)
188 return !bc2; 188 return !bc2;
189 189
190 return bc2 && bc1->bc_key == bc2->bc_k 190 return bc2 && bc1->bc_key == bc2->bc_key;
191 } 191 }
192 192
193 bool bio_crypt_rq_ctx_compatible(struct reques 193 bool bio_crypt_rq_ctx_compatible(struct request *rq, struct bio *bio)
194 { 194 {
195 return bio_crypt_ctx_compatible(rq->cr 195 return bio_crypt_ctx_compatible(rq->crypt_ctx, bio->bi_crypt_context);
196 } 196 }
197 197
198 /* 198 /*
199 * Checks that two bio crypt contexts are comp 199 * Checks that two bio crypt contexts are compatible, and also
200 * that their data_unit_nums are continuous (a 200 * that their data_unit_nums are continuous (and can hence be merged)
201 * in the order @bc1 followed by @bc2. 201 * in the order @bc1 followed by @bc2.
202 */ 202 */
203 bool bio_crypt_ctx_mergeable(struct bio_crypt_ 203 bool bio_crypt_ctx_mergeable(struct bio_crypt_ctx *bc1, unsigned int bc1_bytes,
204 struct bio_crypt_ 204 struct bio_crypt_ctx *bc2)
205 { 205 {
206 if (!bio_crypt_ctx_compatible(bc1, bc2 206 if (!bio_crypt_ctx_compatible(bc1, bc2))
207 return false; 207 return false;
208 208
209 return !bc1 || bio_crypt_dun_is_contig 209 return !bc1 || bio_crypt_dun_is_contiguous(bc1, bc1_bytes, bc2->bc_dun);
210 } 210 }
211 211
212 /* Check that all I/O segments are data unit a 212 /* Check that all I/O segments are data unit aligned. */
213 static bool bio_crypt_check_alignment(struct b 213 static bool bio_crypt_check_alignment(struct bio *bio)
214 { 214 {
215 const unsigned int data_unit_size = 215 const unsigned int data_unit_size =
216 bio->bi_crypt_context->bc_key- 216 bio->bi_crypt_context->bc_key->crypto_cfg.data_unit_size;
217 struct bvec_iter iter; 217 struct bvec_iter iter;
218 struct bio_vec bv; 218 struct bio_vec bv;
219 219
220 bio_for_each_segment(bv, bio, iter) { 220 bio_for_each_segment(bv, bio, iter) {
221 if (!IS_ALIGNED(bv.bv_len | bv 221 if (!IS_ALIGNED(bv.bv_len | bv.bv_offset, data_unit_size))
222 return false; 222 return false;
223 } 223 }
224 224
225 return true; 225 return true;
226 } 226 }
227 227
228 blk_status_t __blk_crypto_rq_get_keyslot(struc 228 blk_status_t __blk_crypto_rq_get_keyslot(struct request *rq)
229 { 229 {
230 return blk_crypto_get_keyslot(rq->q->c 230 return blk_crypto_get_keyslot(rq->q->crypto_profile,
231 rq->cryp 231 rq->crypt_ctx->bc_key,
232 &rq->cry 232 &rq->crypt_keyslot);
233 } 233 }
234 234
235 void __blk_crypto_rq_put_keyslot(struct reques 235 void __blk_crypto_rq_put_keyslot(struct request *rq)
236 { 236 {
237 blk_crypto_put_keyslot(rq->crypt_keysl 237 blk_crypto_put_keyslot(rq->crypt_keyslot);
238 rq->crypt_keyslot = NULL; 238 rq->crypt_keyslot = NULL;
239 } 239 }
240 240
241 void __blk_crypto_free_request(struct request 241 void __blk_crypto_free_request(struct request *rq)
242 { 242 {
243 /* The keyslot, if one was needed, sho 243 /* The keyslot, if one was needed, should have been released earlier. */
244 if (WARN_ON_ONCE(rq->crypt_keyslot)) 244 if (WARN_ON_ONCE(rq->crypt_keyslot))
245 __blk_crypto_rq_put_keyslot(rq 245 __blk_crypto_rq_put_keyslot(rq);
246 246
247 mempool_free(rq->crypt_ctx, bio_crypt_ 247 mempool_free(rq->crypt_ctx, bio_crypt_ctx_pool);
248 rq->crypt_ctx = NULL; 248 rq->crypt_ctx = NULL;
249 } 249 }
250 250
251 /** 251 /**
252 * __blk_crypto_bio_prep - Prepare bio for inl 252 * __blk_crypto_bio_prep - Prepare bio for inline encryption
253 * 253 *
254 * @bio_ptr: pointer to original bio pointer 254 * @bio_ptr: pointer to original bio pointer
255 * 255 *
256 * If the bio crypt context provided for the b 256 * If the bio crypt context provided for the bio is supported by the underlying
257 * device's inline encryption hardware, do not 257 * device's inline encryption hardware, do nothing.
258 * 258 *
259 * Otherwise, try to perform en/decryption for 259 * Otherwise, try to perform en/decryption for this bio by falling back to the
260 * kernel crypto API. When the crypto API fall 260 * kernel crypto API. When the crypto API fallback is used for encryption,
261 * blk-crypto may choose to split the bio into 261 * blk-crypto may choose to split the bio into 2 - the first one that will
262 * continue to be processed and the second one 262 * continue to be processed and the second one that will be resubmitted via
263 * submit_bio_noacct. A bounce bio will be all 263 * submit_bio_noacct. A bounce bio will be allocated to encrypt the contents
264 * of the aforementioned "first one", and *bio 264 * of the aforementioned "first one", and *bio_ptr will be updated to this
265 * bounce bio. 265 * bounce bio.
266 * 266 *
267 * Caller must ensure bio has bio_crypt_ctx. 267 * Caller must ensure bio has bio_crypt_ctx.
268 * 268 *
269 * Return: true on success; false on error (an 269 * Return: true on success; false on error (and bio->bi_status will be set
270 * appropriately, and bio_endio() will 270 * appropriately, and bio_endio() will have been called so bio
271 * submission should abort). 271 * submission should abort).
272 */ 272 */
273 bool __blk_crypto_bio_prep(struct bio **bio_pt 273 bool __blk_crypto_bio_prep(struct bio **bio_ptr)
274 { 274 {
275 struct bio *bio = *bio_ptr; 275 struct bio *bio = *bio_ptr;
276 const struct blk_crypto_key *bc_key = 276 const struct blk_crypto_key *bc_key = bio->bi_crypt_context->bc_key;
277 277
278 /* Error if bio has no data. */ 278 /* Error if bio has no data. */
279 if (WARN_ON_ONCE(!bio_has_data(bio))) 279 if (WARN_ON_ONCE(!bio_has_data(bio))) {
280 bio->bi_status = BLK_STS_IOERR 280 bio->bi_status = BLK_STS_IOERR;
281 goto fail; 281 goto fail;
282 } 282 }
283 283
284 if (!bio_crypt_check_alignment(bio)) { 284 if (!bio_crypt_check_alignment(bio)) {
285 bio->bi_status = BLK_STS_IOERR 285 bio->bi_status = BLK_STS_IOERR;
286 goto fail; 286 goto fail;
287 } 287 }
288 288
289 /* 289 /*
290 * Success if device supports the encr 290 * Success if device supports the encryption context, or if we succeeded
291 * in falling back to the crypto API. 291 * in falling back to the crypto API.
292 */ 292 */
293 if (blk_crypto_config_supported_native 293 if (blk_crypto_config_supported_natively(bio->bi_bdev,
294 294 &bc_key->crypto_cfg))
295 return true; 295 return true;
296 if (blk_crypto_fallback_bio_prep(bio_p 296 if (blk_crypto_fallback_bio_prep(bio_ptr))
297 return true; 297 return true;
298 fail: 298 fail:
299 bio_endio(*bio_ptr); 299 bio_endio(*bio_ptr);
300 return false; 300 return false;
301 } 301 }
302 302
303 int __blk_crypto_rq_bio_prep(struct request *r 303 int __blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio,
304 gfp_t gfp_mask) 304 gfp_t gfp_mask)
305 { 305 {
306 if (!rq->crypt_ctx) { 306 if (!rq->crypt_ctx) {
307 rq->crypt_ctx = mempool_alloc( 307 rq->crypt_ctx = mempool_alloc(bio_crypt_ctx_pool, gfp_mask);
308 if (!rq->crypt_ctx) 308 if (!rq->crypt_ctx)
309 return -ENOMEM; 309 return -ENOMEM;
310 } 310 }
311 *rq->crypt_ctx = *bio->bi_crypt_contex 311 *rq->crypt_ctx = *bio->bi_crypt_context;
312 return 0; 312 return 0;
313 } 313 }
314 314
315 /** 315 /**
316 * blk_crypto_init_key() - Prepare a key for u 316 * blk_crypto_init_key() - Prepare a key for use with blk-crypto
317 * @blk_key: Pointer to the blk_crypto_key to 317 * @blk_key: Pointer to the blk_crypto_key to initialize.
318 * @raw_key: Pointer to the raw key. Must be t 318 * @raw_key: Pointer to the raw key. Must be the correct length for the chosen
319 * @crypto_mode; see blk_crypto_mode 319 * @crypto_mode; see blk_crypto_modes[].
320 * @crypto_mode: identifier for the encryption 320 * @crypto_mode: identifier for the encryption algorithm to use
321 * @dun_bytes: number of bytes that will be us 321 * @dun_bytes: number of bytes that will be used to specify the DUN when this
322 * key is used 322 * key is used
323 * @data_unit_size: the data unit size to use 323 * @data_unit_size: the data unit size to use for en/decryption
324 * 324 *
325 * Return: 0 on success, -errno on failure. T 325 * Return: 0 on success, -errno on failure. The caller is responsible for
326 * zeroizing both blk_key and raw_key 326 * zeroizing both blk_key and raw_key when done with them.
327 */ 327 */
328 int blk_crypto_init_key(struct blk_crypto_key 328 int blk_crypto_init_key(struct blk_crypto_key *blk_key, const u8 *raw_key,
329 enum blk_crypto_mode_n 329 enum blk_crypto_mode_num crypto_mode,
330 unsigned int dun_bytes 330 unsigned int dun_bytes,
331 unsigned int data_unit 331 unsigned int data_unit_size)
332 { 332 {
333 const struct blk_crypto_mode *mode; 333 const struct blk_crypto_mode *mode;
334 334
335 memset(blk_key, 0, sizeof(*blk_key)); 335 memset(blk_key, 0, sizeof(*blk_key));
336 336
337 if (crypto_mode >= ARRAY_SIZE(blk_cryp 337 if (crypto_mode >= ARRAY_SIZE(blk_crypto_modes))
338 return -EINVAL; 338 return -EINVAL;
339 339
340 mode = &blk_crypto_modes[crypto_mode]; 340 mode = &blk_crypto_modes[crypto_mode];
341 if (mode->keysize == 0) 341 if (mode->keysize == 0)
342 return -EINVAL; 342 return -EINVAL;
343 343
344 if (dun_bytes == 0 || dun_bytes > mode 344 if (dun_bytes == 0 || dun_bytes > mode->ivsize)
345 return -EINVAL; 345 return -EINVAL;
346 346
347 if (!is_power_of_2(data_unit_size)) 347 if (!is_power_of_2(data_unit_size))
348 return -EINVAL; 348 return -EINVAL;
349 349
350 blk_key->crypto_cfg.crypto_mode = cryp 350 blk_key->crypto_cfg.crypto_mode = crypto_mode;
351 blk_key->crypto_cfg.dun_bytes = dun_by 351 blk_key->crypto_cfg.dun_bytes = dun_bytes;
352 blk_key->crypto_cfg.data_unit_size = d 352 blk_key->crypto_cfg.data_unit_size = data_unit_size;
353 blk_key->data_unit_size_bits = ilog2(d 353 blk_key->data_unit_size_bits = ilog2(data_unit_size);
354 blk_key->size = mode->keysize; 354 blk_key->size = mode->keysize;
355 memcpy(blk_key->raw, raw_key, mode->ke 355 memcpy(blk_key->raw, raw_key, mode->keysize);
356 356
357 return 0; 357 return 0;
358 } 358 }
359 359
360 bool blk_crypto_config_supported_natively(stru 360 bool blk_crypto_config_supported_natively(struct block_device *bdev,
361 cons 361 const struct blk_crypto_config *cfg)
362 { 362 {
363 return __blk_crypto_cfg_supported(bdev 363 return __blk_crypto_cfg_supported(bdev_get_queue(bdev)->crypto_profile,
364 cfg) 364 cfg);
365 } 365 }
366 366
367 /* 367 /*
368 * Check if bios with @cfg can be en/decrypted 368 * Check if bios with @cfg can be en/decrypted by blk-crypto (i.e. either the
369 * block_device it's submitted to supports inl 369 * block_device it's submitted to supports inline crypto, or the
370 * blk-crypto-fallback is enabled and supports 370 * blk-crypto-fallback is enabled and supports the cfg).
371 */ 371 */
372 bool blk_crypto_config_supported(struct block_ 372 bool blk_crypto_config_supported(struct block_device *bdev,
373 const struct 373 const struct blk_crypto_config *cfg)
374 { 374 {
375 return IS_ENABLED(CONFIG_BLK_INLINE_EN 375 return IS_ENABLED(CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK) ||
376 blk_crypto_config_supported_nat 376 blk_crypto_config_supported_natively(bdev, cfg);
377 } 377 }
378 378
379 /** 379 /**
380 * blk_crypto_start_using_key() - Start using 380 * blk_crypto_start_using_key() - Start using a blk_crypto_key on a device
381 * @bdev: block device to operate on 381 * @bdev: block device to operate on
382 * @key: A key to use on the device 382 * @key: A key to use on the device
383 * 383 *
384 * Upper layers must call this function to ens 384 * Upper layers must call this function to ensure that either the hardware
385 * supports the key's crypto settings, or the 385 * supports the key's crypto settings, or the crypto API fallback has transforms
386 * for the needed mode allocated and ready to 386 * for the needed mode allocated and ready to go. This function may allocate
387 * an skcipher, and *should not* be called fro 387 * an skcipher, and *should not* be called from the data path, since that might
388 * cause a deadlock 388 * cause a deadlock
389 * 389 *
390 * Return: 0 on success; -ENOPKG if the hardwa 390 * Return: 0 on success; -ENOPKG if the hardware doesn't support the key and
391 * blk-crypto-fallback is either disab 391 * blk-crypto-fallback is either disabled or the needed algorithm
392 * is disabled in the crypto API; or a 392 * is disabled in the crypto API; or another -errno code.
393 */ 393 */
394 int blk_crypto_start_using_key(struct block_de 394 int blk_crypto_start_using_key(struct block_device *bdev,
395 const struct bl 395 const struct blk_crypto_key *key)
396 { 396 {
397 if (blk_crypto_config_supported_native 397 if (blk_crypto_config_supported_natively(bdev, &key->crypto_cfg))
398 return 0; 398 return 0;
399 return blk_crypto_fallback_start_using 399 return blk_crypto_fallback_start_using_mode(key->crypto_cfg.crypto_mode);
400 } 400 }
401 401
402 /** 402 /**
403 * blk_crypto_evict_key() - Evict a blk_crypto 403 * blk_crypto_evict_key() - Evict a blk_crypto_key from a block_device
404 * @bdev: a block_device on which I/O using th 404 * @bdev: a block_device on which I/O using the key may have been done
405 * @key: the key to evict 405 * @key: the key to evict
406 * 406 *
407 * For a given block_device, this function rem 407 * For a given block_device, this function removes the given blk_crypto_key from
408 * the keyslot management structures and evict 408 * the keyslot management structures and evicts it from any underlying hardware
409 * keyslot(s) or blk-crypto-fallback keyslot i 409 * keyslot(s) or blk-crypto-fallback keyslot it may have been programmed into.
410 * 410 *
411 * Upper layers must call this before freeing 411 * Upper layers must call this before freeing the blk_crypto_key. It must be
412 * called for every block_device the key may h 412 * called for every block_device the key may have been used on. The key must no
413 * longer be in use by any I/O when this funct 413 * longer be in use by any I/O when this function is called.
414 * 414 *
415 * Context: May sleep. 415 * Context: May sleep.
416 */ 416 */
417 void blk_crypto_evict_key(struct block_device 417 void blk_crypto_evict_key(struct block_device *bdev,
418 const struct blk_cry 418 const struct blk_crypto_key *key)
419 { 419 {
420 struct request_queue *q = bdev_get_que 420 struct request_queue *q = bdev_get_queue(bdev);
421 int err; 421 int err;
422 422
423 if (blk_crypto_config_supported_native 423 if (blk_crypto_config_supported_natively(bdev, &key->crypto_cfg))
424 err = __blk_crypto_evict_key(q 424 err = __blk_crypto_evict_key(q->crypto_profile, key);
425 else 425 else
426 err = blk_crypto_fallback_evic 426 err = blk_crypto_fallback_evict_key(key);
427 /* 427 /*
428 * An error can only occur here if the 428 * An error can only occur here if the key failed to be evicted from a
429 * keyslot (due to a hardware or drive 429 * keyslot (due to a hardware or driver issue) or is allegedly still in
430 * use by I/O (due to a kernel bug). 430 * use by I/O (due to a kernel bug). Even in these cases, the key is
431 * still unlinked from the keyslot man 431 * still unlinked from the keyslot management structures, and the caller
432 * is allowed and expected to free it 432 * is allowed and expected to free it right away. There's nothing
433 * callers can do to handle errors, so 433 * callers can do to handle errors, so just log them and return void.
434 */ 434 */
435 if (err) 435 if (err)
436 pr_warn_ratelimited("%pg: erro 436 pr_warn_ratelimited("%pg: error %d evicting key\n", bdev, err);
437 } 437 }
438 EXPORT_SYMBOL_GPL(blk_crypto_evict_key); 438 EXPORT_SYMBOL_GPL(blk_crypto_evict_key);
439 439
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