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15#include <crypto/hash.h>
16#include <crypto/if_alg.h>
17#include <linux/init.h>
18#include <linux/kernel.h>
19#include <linux/mm.h>
20#include <linux/module.h>
21#include <linux/net.h>
22#include <net/sock.h>
23
24struct hash_ctx {
25 struct af_alg_sgl sgl;
26
27 u8 *result;
28
29 struct af_alg_completion completion;
30
31 unsigned int len;
32 bool more;
33
34 struct ahash_request req;
35};
36
37static int hash_sendmsg(struct socket *sock, struct msghdr *msg,
38 size_t ignored)
39{
40 int limit = ALG_MAX_PAGES * PAGE_SIZE;
41 struct sock *sk = sock->sk;
42 struct alg_sock *ask = alg_sk(sk);
43 struct hash_ctx *ctx = ask->private;
44 long copied = 0;
45 int err;
46
47 if (limit > sk->sk_sndbuf)
48 limit = sk->sk_sndbuf;
49
50 lock_sock(sk);
51 if (!ctx->more) {
52 err = crypto_ahash_init(&ctx->req);
53 if (err)
54 goto unlock;
55 }
56
57 ctx->more = 0;
58
59 while (msg_data_left(msg)) {
60 int len = msg_data_left(msg);
61
62 if (len > limit)
63 len = limit;
64
65 len = af_alg_make_sg(&ctx->sgl, &msg->msg_iter, len);
66 if (len < 0) {
67 err = copied ? 0 : len;
68 goto unlock;
69 }
70
71 ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, NULL, len);
72
73 err = af_alg_wait_for_completion(crypto_ahash_update(&ctx->req),
74 &ctx->completion);
75 af_alg_free_sg(&ctx->sgl);
76 if (err)
77 goto unlock;
78
79 copied += len;
80 iov_iter_advance(&msg->msg_iter, len);
81 }
82
83 err = 0;
84
85 ctx->more = msg->msg_flags & MSG_MORE;
86 if (!ctx->more) {
87 ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
88 err = af_alg_wait_for_completion(crypto_ahash_final(&ctx->req),
89 &ctx->completion);
90 }
91
92unlock:
93 release_sock(sk);
94
95 return err ?: copied;
96}
97
98static ssize_t hash_sendpage(struct socket *sock, struct page *page,
99 int offset, size_t size, int flags)
100{
101 struct sock *sk = sock->sk;
102 struct alg_sock *ask = alg_sk(sk);
103 struct hash_ctx *ctx = ask->private;
104 int err;
105
106 if (flags & MSG_SENDPAGE_NOTLAST)
107 flags |= MSG_MORE;
108
109 lock_sock(sk);
110 sg_init_table(ctx->sgl.sg, 1);
111 sg_set_page(ctx->sgl.sg, page, size, offset);
112
113 ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, ctx->result, size);
114
115 if (!(flags & MSG_MORE)) {
116 if (ctx->more)
117 err = crypto_ahash_finup(&ctx->req);
118 else
119 err = crypto_ahash_digest(&ctx->req);
120 } else {
121 if (!ctx->more) {
122 err = crypto_ahash_init(&ctx->req);
123 if (err)
124 goto unlock;
125 }
126
127 err = crypto_ahash_update(&ctx->req);
128 }
129
130 err = af_alg_wait_for_completion(err, &ctx->completion);
131 if (err)
132 goto unlock;
133
134 ctx->more = flags & MSG_MORE;
135
136unlock:
137 release_sock(sk);
138
139 return err ?: size;
140}
141
142static int hash_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
143 int flags)
144{
145 struct sock *sk = sock->sk;
146 struct alg_sock *ask = alg_sk(sk);
147 struct hash_ctx *ctx = ask->private;
148 unsigned ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
149 int err;
150
151 if (len > ds)
152 len = ds;
153 else if (len < ds)
154 msg->msg_flags |= MSG_TRUNC;
155
156 lock_sock(sk);
157 if (ctx->more) {
158 ctx->more = 0;
159 ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
160 err = af_alg_wait_for_completion(crypto_ahash_final(&ctx->req),
161 &ctx->completion);
162 if (err)
163 goto unlock;
164 }
165
166 err = memcpy_to_msg(msg, ctx->result, len);
167
168unlock:
169 release_sock(sk);
170
171 return err ?: len;
172}
173
174static int hash_accept(struct socket *sock, struct socket *newsock, int flags)
175{
176 struct sock *sk = sock->sk;
177 struct alg_sock *ask = alg_sk(sk);
178 struct hash_ctx *ctx = ask->private;
179 struct ahash_request *req = &ctx->req;
180 char state[crypto_ahash_statesize(crypto_ahash_reqtfm(req))];
181 struct sock *sk2;
182 struct alg_sock *ask2;
183 struct hash_ctx *ctx2;
184 int err;
185
186 err = crypto_ahash_export(req, state);
187 if (err)
188 return err;
189
190 err = af_alg_accept(ask->parent, newsock);
191 if (err)
192 return err;
193
194 sk2 = newsock->sk;
195 ask2 = alg_sk(sk2);
196 ctx2 = ask2->private;
197 ctx2->more = 1;
198
199 err = crypto_ahash_import(&ctx2->req, state);
200 if (err) {
201 sock_orphan(sk2);
202 sock_put(sk2);
203 }
204
205 return err;
206}
207
208static struct proto_ops algif_hash_ops = {
209 .family = PF_ALG,
210
211 .connect = sock_no_connect,
212 .socketpair = sock_no_socketpair,
213 .getname = sock_no_getname,
214 .ioctl = sock_no_ioctl,
215 .listen = sock_no_listen,
216 .shutdown = sock_no_shutdown,
217 .getsockopt = sock_no_getsockopt,
218 .mmap = sock_no_mmap,
219 .bind = sock_no_bind,
220 .setsockopt = sock_no_setsockopt,
221 .poll = sock_no_poll,
222
223 .release = af_alg_release,
224 .sendmsg = hash_sendmsg,
225 .sendpage = hash_sendpage,
226 .recvmsg = hash_recvmsg,
227 .accept = hash_accept,
228};
229
230static void *hash_bind(const char *name, u32 type, u32 mask)
231{
232 return crypto_alloc_ahash(name, type, mask);
233}
234
235static void hash_release(void *private)
236{
237 crypto_free_ahash(private);
238}
239
240static int hash_setkey(void *private, const u8 *key, unsigned int keylen)
241{
242 return crypto_ahash_setkey(private, key, keylen);
243}
244
245static void hash_sock_destruct(struct sock *sk)
246{
247 struct alg_sock *ask = alg_sk(sk);
248 struct hash_ctx *ctx = ask->private;
249
250 sock_kzfree_s(sk, ctx->result,
251 crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req)));
252 sock_kfree_s(sk, ctx, ctx->len);
253 af_alg_release_parent(sk);
254}
255
256static int hash_accept_parent(void *private, struct sock *sk)
257{
258 struct hash_ctx *ctx;
259 struct alg_sock *ask = alg_sk(sk);
260 unsigned len = sizeof(*ctx) + crypto_ahash_reqsize(private);
261 unsigned ds = crypto_ahash_digestsize(private);
262
263 ctx = sock_kmalloc(sk, len, GFP_KERNEL);
264 if (!ctx)
265 return -ENOMEM;
266
267 ctx->result = sock_kmalloc(sk, ds, GFP_KERNEL);
268 if (!ctx->result) {
269 sock_kfree_s(sk, ctx, len);
270 return -ENOMEM;
271 }
272
273 memset(ctx->result, 0, ds);
274
275 ctx->len = len;
276 ctx->more = 0;
277 af_alg_init_completion(&ctx->completion);
278
279 ask->private = ctx;
280
281 ahash_request_set_tfm(&ctx->req, private);
282 ahash_request_set_callback(&ctx->req, CRYPTO_TFM_REQ_MAY_BACKLOG,
283 af_alg_complete, &ctx->completion);
284
285 sk->sk_destruct = hash_sock_destruct;
286
287 return 0;
288}
289
290static const struct af_alg_type algif_type_hash = {
291 .bind = hash_bind,
292 .release = hash_release,
293 .setkey = hash_setkey,
294 .accept = hash_accept_parent,
295 .ops = &algif_hash_ops,
296 .name = "hash",
297 .owner = THIS_MODULE
298};
299
300static int __init algif_hash_init(void)
301{
302 return af_alg_register_type(&algif_type_hash);
303}
304
305static void __exit algif_hash_exit(void)
306{
307 int err = af_alg_unregister_type(&algif_type_hash);
308 BUG_ON(err);
309}
310
311module_init(algif_hash_init);
312module_exit(algif_hash_exit);
313MODULE_LICENSE("GPL");
314
