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10#include <linux/module.h>
11#include <linux/sched.h>
12#include <linux/scatterlist.h>
13#include <linux/crypto.h>
14#include <crypto/algapi.h>
15#include <crypto/internal/rsa.h>
16#include <crypto/internal/akcipher.h>
17#include <crypto/akcipher.h>
18#include <crypto/scatterwalk.h>
19
20#include "ccp-crypto.h"
21
22static inline struct akcipher_request *akcipher_request_cast(
23 struct crypto_async_request *req)
24{
25 return container_of(req, struct akcipher_request, base);
26}
27
28static inline int ccp_copy_and_save_keypart(u8 **kpbuf, unsigned int *kplen,
29 const u8 *buf, size_t sz)
30{
31 int nskip;
32
33 for (nskip = 0; nskip < sz; nskip++)
34 if (buf[nskip])
35 break;
36 *kplen = sz - nskip;
37 *kpbuf = kmemdup(buf + nskip, *kplen, GFP_KERNEL);
38 if (!*kpbuf)
39 return -ENOMEM;
40
41 return 0;
42}
43
44static int ccp_rsa_complete(struct crypto_async_request *async_req, int ret)
45{
46 struct akcipher_request *req = akcipher_request_cast(async_req);
47 struct ccp_rsa_req_ctx *rctx = akcipher_request_ctx(req);
48
49 if (ret)
50 return ret;
51
52 req->dst_len = rctx->cmd.u.rsa.key_size >> 3;
53
54 return 0;
55}
56
57static unsigned int ccp_rsa_maxsize(struct crypto_akcipher *tfm)
58{
59 struct ccp_ctx *ctx = akcipher_tfm_ctx(tfm);
60
61 return ctx->u.rsa.n_len;
62}
63
64static int ccp_rsa_crypt(struct akcipher_request *req, bool encrypt)
65{
66 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
67 struct ccp_ctx *ctx = akcipher_tfm_ctx(tfm);
68 struct ccp_rsa_req_ctx *rctx = akcipher_request_ctx(req);
69 int ret = 0;
70
71 memset(&rctx->cmd, 0, sizeof(rctx->cmd));
72 INIT_LIST_HEAD(&rctx->cmd.entry);
73 rctx->cmd.engine = CCP_ENGINE_RSA;
74
75 rctx->cmd.u.rsa.key_size = ctx->u.rsa.key_len;
76 if (encrypt) {
77 rctx->cmd.u.rsa.exp = &ctx->u.rsa.e_sg;
78 rctx->cmd.u.rsa.exp_len = ctx->u.rsa.e_len;
79 } else {
80 rctx->cmd.u.rsa.exp = &ctx->u.rsa.d_sg;
81 rctx->cmd.u.rsa.exp_len = ctx->u.rsa.d_len;
82 }
83 rctx->cmd.u.rsa.mod = &ctx->u.rsa.n_sg;
84 rctx->cmd.u.rsa.mod_len = ctx->u.rsa.n_len;
85 rctx->cmd.u.rsa.src = req->src;
86 rctx->cmd.u.rsa.src_len = req->src_len;
87 rctx->cmd.u.rsa.dst = req->dst;
88
89 ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
90
91 return ret;
92}
93
94static int ccp_rsa_encrypt(struct akcipher_request *req)
95{
96 return ccp_rsa_crypt(req, true);
97}
98
99static int ccp_rsa_decrypt(struct akcipher_request *req)
100{
101 return ccp_rsa_crypt(req, false);
102}
103
104static int ccp_check_key_length(unsigned int len)
105{
106
107 if (len < 8 || len > 4096)
108 return -EINVAL;
109 return 0;
110}
111
112static void ccp_rsa_free_key_bufs(struct ccp_ctx *ctx)
113{
114
115 kfree_sensitive(ctx->u.rsa.e_buf);
116 ctx->u.rsa.e_buf = NULL;
117 ctx->u.rsa.e_len = 0;
118 kfree_sensitive(ctx->u.rsa.n_buf);
119 ctx->u.rsa.n_buf = NULL;
120 ctx->u.rsa.n_len = 0;
121 kfree_sensitive(ctx->u.rsa.d_buf);
122 ctx->u.rsa.d_buf = NULL;
123 ctx->u.rsa.d_len = 0;
124}
125
126static int ccp_rsa_setkey(struct crypto_akcipher *tfm, const void *key,
127 unsigned int keylen, bool private)
128{
129 struct ccp_ctx *ctx = akcipher_tfm_ctx(tfm);
130 struct rsa_key raw_key;
131 int ret;
132
133 ccp_rsa_free_key_bufs(ctx);
134 memset(&raw_key, 0, sizeof(raw_key));
135
136
137 if (private)
138 ret = rsa_parse_priv_key(&raw_key, key, keylen);
139 else
140 ret = rsa_parse_pub_key(&raw_key, key, keylen);
141 if (ret)
142 goto n_key;
143
144 ret = ccp_copy_and_save_keypart(&ctx->u.rsa.n_buf, &ctx->u.rsa.n_len,
145 raw_key.n, raw_key.n_sz);
146 if (ret)
147 goto key_err;
148 sg_init_one(&ctx->u.rsa.n_sg, ctx->u.rsa.n_buf, ctx->u.rsa.n_len);
149
150 ctx->u.rsa.key_len = ctx->u.rsa.n_len << 3;
151 if (ccp_check_key_length(ctx->u.rsa.key_len)) {
152 ret = -EINVAL;
153 goto key_err;
154 }
155
156 ret = ccp_copy_and_save_keypart(&ctx->u.rsa.e_buf, &ctx->u.rsa.e_len,
157 raw_key.e, raw_key.e_sz);
158 if (ret)
159 goto key_err;
160 sg_init_one(&ctx->u.rsa.e_sg, ctx->u.rsa.e_buf, ctx->u.rsa.e_len);
161
162 if (private) {
163 ret = ccp_copy_and_save_keypart(&ctx->u.rsa.d_buf,
164 &ctx->u.rsa.d_len,
165 raw_key.d, raw_key.d_sz);
166 if (ret)
167 goto key_err;
168 sg_init_one(&ctx->u.rsa.d_sg,
169 ctx->u.rsa.d_buf, ctx->u.rsa.d_len);
170 }
171
172 return 0;
173
174key_err:
175 ccp_rsa_free_key_bufs(ctx);
176
177n_key:
178 return ret;
179}
180
181static int ccp_rsa_setprivkey(struct crypto_akcipher *tfm, const void *key,
182 unsigned int keylen)
183{
184 return ccp_rsa_setkey(tfm, key, keylen, true);
185}
186
187static int ccp_rsa_setpubkey(struct crypto_akcipher *tfm, const void *key,
188 unsigned int keylen)
189{
190 return ccp_rsa_setkey(tfm, key, keylen, false);
191}
192
193static int ccp_rsa_init_tfm(struct crypto_akcipher *tfm)
194{
195 struct ccp_ctx *ctx = akcipher_tfm_ctx(tfm);
196
197 akcipher_set_reqsize(tfm, sizeof(struct ccp_rsa_req_ctx));
198 ctx->complete = ccp_rsa_complete;
199
200 return 0;
201}
202
203static void ccp_rsa_exit_tfm(struct crypto_akcipher *tfm)
204{
205 struct ccp_ctx *ctx = crypto_tfm_ctx(&tfm->base);
206
207 ccp_rsa_free_key_bufs(ctx);
208}
209
210static struct akcipher_alg ccp_rsa_defaults = {
211 .encrypt = ccp_rsa_encrypt,
212 .decrypt = ccp_rsa_decrypt,
213 .set_pub_key = ccp_rsa_setpubkey,
214 .set_priv_key = ccp_rsa_setprivkey,
215 .max_size = ccp_rsa_maxsize,
216 .init = ccp_rsa_init_tfm,
217 .exit = ccp_rsa_exit_tfm,
218 .base = {
219 .cra_name = "rsa",
220 .cra_driver_name = "rsa-ccp",
221 .cra_priority = CCP_CRA_PRIORITY,
222 .cra_module = THIS_MODULE,
223 .cra_ctxsize = 2 * sizeof(struct ccp_ctx),
224 },
225};
226
227struct ccp_rsa_def {
228 unsigned int version;
229 const char *name;
230 const char *driver_name;
231 unsigned int reqsize;
232 struct akcipher_alg *alg_defaults;
233};
234
235static struct ccp_rsa_def rsa_algs[] = {
236 {
237 .version = CCP_VERSION(3, 0),
238 .name = "rsa",
239 .driver_name = "rsa-ccp",
240 .reqsize = sizeof(struct ccp_rsa_req_ctx),
241 .alg_defaults = &ccp_rsa_defaults,
242 }
243};
244
245static int ccp_register_rsa_alg(struct list_head *head,
246 const struct ccp_rsa_def *def)
247{
248 struct ccp_crypto_akcipher_alg *ccp_alg;
249 struct akcipher_alg *alg;
250 int ret;
251
252 ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
253 if (!ccp_alg)
254 return -ENOMEM;
255
256 INIT_LIST_HEAD(&ccp_alg->entry);
257
258 alg = &ccp_alg->alg;
259 *alg = *def->alg_defaults;
260 snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
261 snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
262 def->driver_name);
263 ret = crypto_register_akcipher(alg);
264 if (ret) {
265 pr_err("%s akcipher algorithm registration error (%d)\n",
266 alg->base.cra_name, ret);
267 kfree(ccp_alg);
268 return ret;
269 }
270
271 list_add(&ccp_alg->entry, head);
272
273 return 0;
274}
275
276int ccp_register_rsa_algs(struct list_head *head)
277{
278 int i, ret;
279 unsigned int ccpversion = ccp_version();
280
281
282
283
284 for (i = 0; i < ARRAY_SIZE(rsa_algs); i++) {
285 if (rsa_algs[i].version > ccpversion)
286 continue;
287 ret = ccp_register_rsa_alg(head, &rsa_algs[i]);
288 if (ret)
289 return ret;
290 }
291
292 return 0;
293}
294
