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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 kiocb *unused, struct socket *sock,
38 struct msghdr *msg, 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 unsigned long iovlen;
45 struct iovec *iov;
46 long copied = 0;
47 int err;
48
49 if (limit > sk->sk_sndbuf)
50 limit = sk->sk_sndbuf;
51
52 lock_sock(sk);
53 if (!ctx->more) {
54 err = crypto_ahash_init(&ctx->req);
55 if (err)
56 goto unlock;
57 }
58
59 ctx->more = 0;
60
61 for (iov = msg->msg_iov, iovlen = msg->msg_iovlen; iovlen > 0;
62 iovlen--, iov++) {
63 unsigned long seglen = iov->iov_len;
64 char __user *from = iov->iov_base;
65
66 while (seglen) {
67 int len = min_t(unsigned long, seglen, limit);
68 int newlen;
69
70 newlen = af_alg_make_sg(&ctx->sgl, from, len, 0);
71 if (newlen < 0) {
72 err = copied ? 0 : newlen;
73 goto unlock;
74 }
75
76 ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, NULL,
77 newlen);
78
79 err = af_alg_wait_for_completion(
80 crypto_ahash_update(&ctx->req),
81 &ctx->completion);
82
83 af_alg_free_sg(&ctx->sgl);
84
85 if (err)
86 goto unlock;
87
88 seglen -= newlen;
89 from += newlen;
90 copied += newlen;
91 }
92 }
93
94 err = 0;
95
96 ctx->more = msg->msg_flags & MSG_MORE;
97 if (!ctx->more) {
98 ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
99 err = af_alg_wait_for_completion(crypto_ahash_final(&ctx->req),
100 &ctx->completion);
101 }
102
103unlock:
104 release_sock(sk);
105
106 return err ?: copied;
107}
108
109static ssize_t hash_sendpage(struct socket *sock, struct page *page,
110 int offset, size_t size, int flags)
111{
112 struct sock *sk = sock->sk;
113 struct alg_sock *ask = alg_sk(sk);
114 struct hash_ctx *ctx = ask->private;
115 int err;
116
117 lock_sock(sk);
118 sg_init_table(ctx->sgl.sg, 1);
119 sg_set_page(ctx->sgl.sg, page, size, offset);
120
121 ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, ctx->result, size);
122
123 if (!(flags & MSG_MORE)) {
124 if (ctx->more)
125 err = crypto_ahash_finup(&ctx->req);
126 else
127 err = crypto_ahash_digest(&ctx->req);
128 } else {
129 if (!ctx->more) {
130 err = crypto_ahash_init(&ctx->req);
131 if (err)
132 goto unlock;
133 }
134
135 err = crypto_ahash_update(&ctx->req);
136 }
137
138 err = af_alg_wait_for_completion(err, &ctx->completion);
139 if (err)
140 goto unlock;
141
142 ctx->more = flags & MSG_MORE;
143
144unlock:
145 release_sock(sk);
146
147 return err ?: size;
148}
149
150static int hash_recvmsg(struct kiocb *unused, struct socket *sock,
151 struct msghdr *msg, size_t len, int flags)
152{
153 struct sock *sk = sock->sk;
154 struct alg_sock *ask = alg_sk(sk);
155 struct hash_ctx *ctx = ask->private;
156 unsigned ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
157 int err;
158
159 if (len > ds)
160 len = ds;
161 else if (len < ds)
162 msg->msg_flags |= MSG_TRUNC;
163
164 msg->msg_namelen = 0;
165
166 lock_sock(sk);
167 if (ctx->more) {
168 ctx->more = 0;
169 ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
170 err = af_alg_wait_for_completion(crypto_ahash_final(&ctx->req),
171 &ctx->completion);
172 if (err)
173 goto unlock;
174 }
175
176 err = memcpy_toiovec(msg->msg_iov, ctx->result, len);
177
178unlock:
179 release_sock(sk);
180
181 return err ?: len;
182}
183
184static int hash_accept(struct socket *sock, struct socket *newsock, int flags)
185{
186 struct sock *sk = sock->sk;
187 struct alg_sock *ask = alg_sk(sk);
188 struct hash_ctx *ctx = ask->private;
189 struct ahash_request *req = &ctx->req;
190 char state[crypto_ahash_statesize(crypto_ahash_reqtfm(req))];
191 struct sock *sk2;
192 struct alg_sock *ask2;
193 struct hash_ctx *ctx2;
194 int err;
195
196 err = crypto_ahash_export(req, state);
197 if (err)
198 return err;
199
200 err = af_alg_accept(ask->parent, newsock);
201 if (err)
202 return err;
203
204 sk2 = newsock->sk;
205 ask2 = alg_sk(sk2);
206 ctx2 = ask2->private;
207 ctx2->more = 1;
208
209 err = crypto_ahash_import(&ctx2->req, state);
210 if (err) {
211 sock_orphan(sk2);
212 sock_put(sk2);
213 }
214
215 return err;
216}
217
218static struct proto_ops algif_hash_ops = {
219 .family = PF_ALG,
220
221 .connect = sock_no_connect,
222 .socketpair = sock_no_socketpair,
223 .getname = sock_no_getname,
224 .ioctl = sock_no_ioctl,
225 .listen = sock_no_listen,
226 .shutdown = sock_no_shutdown,
227 .getsockopt = sock_no_getsockopt,
228 .mmap = sock_no_mmap,
229 .bind = sock_no_bind,
230 .setsockopt = sock_no_setsockopt,
231 .poll = sock_no_poll,
232
233 .release = af_alg_release,
234 .sendmsg = hash_sendmsg,
235 .sendpage = hash_sendpage,
236 .recvmsg = hash_recvmsg,
237 .accept = hash_accept,
238};
239
240static void *hash_bind(const char *name, u32 type, u32 mask)
241{
242 return crypto_alloc_ahash(name, type, mask);
243}
244
245static void hash_release(void *private)
246{
247 crypto_free_ahash(private);
248}
249
250static int hash_setkey(void *private, const u8 *key, unsigned int keylen)
251{
252 return crypto_ahash_setkey(private, key, keylen);
253}
254
255static void hash_sock_destruct(struct sock *sk)
256{
257 struct alg_sock *ask = alg_sk(sk);
258 struct hash_ctx *ctx = ask->private;
259
260 sock_kfree_s(sk, ctx->result,
261 crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req)));
262 sock_kfree_s(sk, ctx, ctx->len);
263 af_alg_release_parent(sk);
264}
265
266static int hash_accept_parent(void *private, struct sock *sk)
267{
268 struct hash_ctx *ctx;
269 struct alg_sock *ask = alg_sk(sk);
270 unsigned len = sizeof(*ctx) + crypto_ahash_reqsize(private);
271 unsigned ds = crypto_ahash_digestsize(private);
272
273 ctx = sock_kmalloc(sk, len, GFP_KERNEL);
274 if (!ctx)
275 return -ENOMEM;
276
277 ctx->result = sock_kmalloc(sk, ds, GFP_KERNEL);
278 if (!ctx->result) {
279 sock_kfree_s(sk, ctx, len);
280 return -ENOMEM;
281 }
282
283 memset(ctx->result, 0, ds);
284
285 ctx->len = len;
286 ctx->more = 0;
287 af_alg_init_completion(&ctx->completion);
288
289 ask->private = ctx;
290
291 ahash_request_set_tfm(&ctx->req, private);
292 ahash_request_set_callback(&ctx->req, CRYPTO_TFM_REQ_MAY_BACKLOG,
293 af_alg_complete, &ctx->completion);
294
295 sk->sk_destruct = hash_sock_destruct;
296
297 return 0;
298}
299
300static const struct af_alg_type algif_type_hash = {
301 .bind = hash_bind,
302 .release = hash_release,
303 .setkey = hash_setkey,
304 .accept = hash_accept_parent,
305 .ops = &algif_hash_ops,
306 .name = "hash",
307 .owner = THIS_MODULE
308};
309
310static int __init algif_hash_init(void)
311{
312 return af_alg_register_type(&algif_type_hash);
313}
314
315static void __exit algif_hash_exit(void)
316{
317 int err = af_alg_unregister_type(&algif_type_hash);
318 BUG_ON(err);
319}
320
321module_init(algif_hash_init);
322module_exit(algif_hash_exit);
323MODULE_LICENSE("GPL");
324
