1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (C) 2019 Samsung Electronics Co., Ltd.
4 */
5
6 #include <linux/kernel.h>
7 #include <linux/string.h>
8 #include <linux/err.h>
9 #include <linux/slab.h>
10 #include <linux/wait.h>
11 #include <linux/sched.h>
12
13 #include "glob.h"
14 #include "crypto_ctx.h"
15
16 struct crypto_ctx_list {
17 spinlock_t ctx_lock;
18 int avail_ctx;
19 struct list_head idle_ctx;
20 wait_queue_head_t ctx_wait;
21 };
22
23 static struct crypto_ctx_list ctx_list;
24
free_aead(struct crypto_aead * aead)25 static inline void free_aead(struct crypto_aead *aead)
26 {
27 if (aead)
28 crypto_free_aead(aead);
29 }
30
free_shash(struct shash_desc * shash)31 static void free_shash(struct shash_desc *shash)
32 {
33 if (shash) {
34 crypto_free_shash(shash->tfm);
35 kfree(shash);
36 }
37 }
38
alloc_aead(int id)39 static struct crypto_aead *alloc_aead(int id)
40 {
41 struct crypto_aead *tfm = NULL;
42
43 switch (id) {
44 case CRYPTO_AEAD_AES_GCM:
45 tfm = crypto_alloc_aead("gcm(aes)", 0, 0);
46 break;
47 case CRYPTO_AEAD_AES_CCM:
48 tfm = crypto_alloc_aead("ccm(aes)", 0, 0);
49 break;
50 default:
51 pr_err("Does not support encrypt ahead(id : %d)\n", id);
52 return NULL;
53 }
54
55 if (IS_ERR(tfm)) {
56 pr_err("Failed to alloc encrypt aead : %ld\n", PTR_ERR(tfm));
57 return NULL;
58 }
59
60 return tfm;
61 }
62
alloc_shash_desc(int id)63 static struct shash_desc *alloc_shash_desc(int id)
64 {
65 struct crypto_shash *tfm = NULL;
66 struct shash_desc *shash;
67
68 switch (id) {
69 case CRYPTO_SHASH_HMACMD5:
70 tfm = crypto_alloc_shash("hmac(md5)", 0, 0);
71 break;
72 case CRYPTO_SHASH_HMACSHA256:
73 tfm = crypto_alloc_shash("hmac(sha256)", 0, 0);
74 break;
75 case CRYPTO_SHASH_CMACAES:
76 tfm = crypto_alloc_shash("cmac(aes)", 0, 0);
77 break;
78 case CRYPTO_SHASH_SHA256:
79 tfm = crypto_alloc_shash("sha256", 0, 0);
80 break;
81 case CRYPTO_SHASH_SHA512:
82 tfm = crypto_alloc_shash("sha512", 0, 0);
83 break;
84 default:
85 return NULL;
86 }
87
88 if (IS_ERR(tfm))
89 return NULL;
90
91 shash = kzalloc(sizeof(*shash) + crypto_shash_descsize(tfm),
92 GFP_KERNEL);
93 if (!shash)
94 crypto_free_shash(tfm);
95 else
96 shash->tfm = tfm;
97 return shash;
98 }
99
ctx_free(struct ksmbd_crypto_ctx * ctx)100 static void ctx_free(struct ksmbd_crypto_ctx *ctx)
101 {
102 int i;
103
104 for (i = 0; i < CRYPTO_SHASH_MAX; i++)
105 free_shash(ctx->desc[i]);
106 for (i = 0; i < CRYPTO_AEAD_MAX; i++)
107 free_aead(ctx->ccmaes[i]);
108 kfree(ctx);
109 }
110
ksmbd_find_crypto_ctx(void)111 static struct ksmbd_crypto_ctx *ksmbd_find_crypto_ctx(void)
112 {
113 struct ksmbd_crypto_ctx *ctx;
114
115 while (1) {
116 spin_lock(&ctx_list.ctx_lock);
117 if (!list_empty(&ctx_list.idle_ctx)) {
118 ctx = list_entry(ctx_list.idle_ctx.next,
119 struct ksmbd_crypto_ctx,
120 list);
121 list_del(&ctx->list);
122 spin_unlock(&ctx_list.ctx_lock);
123 return ctx;
124 }
125
126 if (ctx_list.avail_ctx > num_online_cpus()) {
127 spin_unlock(&ctx_list.ctx_lock);
128 wait_event(ctx_list.ctx_wait,
129 !list_empty(&ctx_list.idle_ctx));
130 continue;
131 }
132
133 ctx_list.avail_ctx++;
134 spin_unlock(&ctx_list.ctx_lock);
135
136 ctx = kzalloc(sizeof(struct ksmbd_crypto_ctx), GFP_KERNEL);
137 if (!ctx) {
138 spin_lock(&ctx_list.ctx_lock);
139 ctx_list.avail_ctx--;
140 spin_unlock(&ctx_list.ctx_lock);
141 wait_event(ctx_list.ctx_wait,
142 !list_empty(&ctx_list.idle_ctx));
143 continue;
144 }
145 break;
146 }
147 return ctx;
148 }
149
ksmbd_release_crypto_ctx(struct ksmbd_crypto_ctx * ctx)150 void ksmbd_release_crypto_ctx(struct ksmbd_crypto_ctx *ctx)
151 {
152 if (!ctx)
153 return;
154
155 spin_lock(&ctx_list.ctx_lock);
156 if (ctx_list.avail_ctx <= num_online_cpus()) {
157 list_add(&ctx->list, &ctx_list.idle_ctx);
158 spin_unlock(&ctx_list.ctx_lock);
159 wake_up(&ctx_list.ctx_wait);
160 return;
161 }
162
163 ctx_list.avail_ctx--;
164 spin_unlock(&ctx_list.ctx_lock);
165 ctx_free(ctx);
166 }
167
____crypto_shash_ctx_find(int id)168 static struct ksmbd_crypto_ctx *____crypto_shash_ctx_find(int id)
169 {
170 struct ksmbd_crypto_ctx *ctx;
171
172 if (id >= CRYPTO_SHASH_MAX)
173 return NULL;
174
175 ctx = ksmbd_find_crypto_ctx();
176 if (ctx->desc[id])
177 return ctx;
178
179 ctx->desc[id] = alloc_shash_desc(id);
180 if (ctx->desc[id])
181 return ctx;
182 ksmbd_release_crypto_ctx(ctx);
183 return NULL;
184 }
185
ksmbd_crypto_ctx_find_hmacmd5(void)186 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_hmacmd5(void)
187 {
188 return ____crypto_shash_ctx_find(CRYPTO_SHASH_HMACMD5);
189 }
190
ksmbd_crypto_ctx_find_hmacsha256(void)191 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_hmacsha256(void)
192 {
193 return ____crypto_shash_ctx_find(CRYPTO_SHASH_HMACSHA256);
194 }
195
ksmbd_crypto_ctx_find_cmacaes(void)196 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_cmacaes(void)
197 {
198 return ____crypto_shash_ctx_find(CRYPTO_SHASH_CMACAES);
199 }
200
ksmbd_crypto_ctx_find_sha256(void)201 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_sha256(void)
202 {
203 return ____crypto_shash_ctx_find(CRYPTO_SHASH_SHA256);
204 }
205
ksmbd_crypto_ctx_find_sha512(void)206 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_sha512(void)
207 {
208 return ____crypto_shash_ctx_find(CRYPTO_SHASH_SHA512);
209 }
210
____crypto_aead_ctx_find(int id)211 static struct ksmbd_crypto_ctx *____crypto_aead_ctx_find(int id)
212 {
213 struct ksmbd_crypto_ctx *ctx;
214
215 if (id >= CRYPTO_AEAD_MAX)
216 return NULL;
217
218 ctx = ksmbd_find_crypto_ctx();
219 if (ctx->ccmaes[id])
220 return ctx;
221
222 ctx->ccmaes[id] = alloc_aead(id);
223 if (ctx->ccmaes[id])
224 return ctx;
225 ksmbd_release_crypto_ctx(ctx);
226 return NULL;
227 }
228
ksmbd_crypto_ctx_find_gcm(void)229 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_gcm(void)
230 {
231 return ____crypto_aead_ctx_find(CRYPTO_AEAD_AES_GCM);
232 }
233
ksmbd_crypto_ctx_find_ccm(void)234 struct ksmbd_crypto_ctx *ksmbd_crypto_ctx_find_ccm(void)
235 {
236 return ____crypto_aead_ctx_find(CRYPTO_AEAD_AES_CCM);
237 }
238
ksmbd_crypto_destroy(void)239 void ksmbd_crypto_destroy(void)
240 {
241 struct ksmbd_crypto_ctx *ctx;
242
243 while (!list_empty(&ctx_list.idle_ctx)) {
244 ctx = list_entry(ctx_list.idle_ctx.next,
245 struct ksmbd_crypto_ctx,
246 list);
247 list_del(&ctx->list);
248 ctx_free(ctx);
249 }
250 }
251
ksmbd_crypto_create(void)252 int ksmbd_crypto_create(void)
253 {
254 struct ksmbd_crypto_ctx *ctx;
255
256 spin_lock_init(&ctx_list.ctx_lock);
257 INIT_LIST_HEAD(&ctx_list.idle_ctx);
258 init_waitqueue_head(&ctx_list.ctx_wait);
259 ctx_list.avail_ctx = 1;
260
261 ctx = kzalloc(sizeof(struct ksmbd_crypto_ctx), GFP_KERNEL);
262 if (!ctx)
263 return -ENOMEM;
264 list_add(&ctx->list, &ctx_list.idle_ctx);
265 return 0;
266 }
267