1
2 #include <linux/ceph/ceph_debug.h>
3
4 #include <linux/err.h>
5 #include <linux/scatterlist.h>
6 #include <linux/slab.h>
7 #include <crypto/hash.h>
8 #include <linux/key-type.h>
9
10 #include <keys/ceph-type.h>
11 #include <linux/ceph/decode.h>
12 #include "crypto.h"
13
ceph_crypto_key_clone(struct ceph_crypto_key * dst,const struct ceph_crypto_key * src)14 int ceph_crypto_key_clone(struct ceph_crypto_key *dst,
15 const struct ceph_crypto_key *src)
16 {
17 memcpy(dst, src, sizeof(struct ceph_crypto_key));
18 dst->key = kmemdup(src->key, src->len, GFP_NOFS);
19 if (!dst->key)
20 return -ENOMEM;
21 return 0;
22 }
23
ceph_crypto_key_encode(struct ceph_crypto_key * key,void ** p,void * end)24 int ceph_crypto_key_encode(struct ceph_crypto_key *key, void **p, void *end)
25 {
26 if (*p + sizeof(u16) + sizeof(key->created) +
27 sizeof(u16) + key->len > end)
28 return -ERANGE;
29 ceph_encode_16(p, key->type);
30 ceph_encode_copy(p, &key->created, sizeof(key->created));
31 ceph_encode_16(p, key->len);
32 ceph_encode_copy(p, key->key, key->len);
33 return 0;
34 }
35
ceph_crypto_key_decode(struct ceph_crypto_key * key,void ** p,void * end)36 int ceph_crypto_key_decode(struct ceph_crypto_key *key, void **p, void *end)
37 {
38 ceph_decode_need(p, end, 2*sizeof(u16) + sizeof(key->created), bad);
39 key->type = ceph_decode_16(p);
40 ceph_decode_copy(p, &key->created, sizeof(key->created));
41 key->len = ceph_decode_16(p);
42 ceph_decode_need(p, end, key->len, bad);
43 key->key = kmalloc(key->len, GFP_NOFS);
44 if (!key->key)
45 return -ENOMEM;
46 ceph_decode_copy(p, key->key, key->len);
47 return 0;
48
49 bad:
50 dout("failed to decode crypto key\n");
51 return -EINVAL;
52 }
53
ceph_crypto_key_unarmor(struct ceph_crypto_key * key,const char * inkey)54 int ceph_crypto_key_unarmor(struct ceph_crypto_key *key, const char *inkey)
55 {
56 int inlen = strlen(inkey);
57 int blen = inlen * 3 / 4;
58 void *buf, *p;
59 int ret;
60
61 dout("crypto_key_unarmor %s\n", inkey);
62 buf = kmalloc(blen, GFP_NOFS);
63 if (!buf)
64 return -ENOMEM;
65 blen = ceph_unarmor(buf, inkey, inkey+inlen);
66 if (blen < 0) {
67 kfree(buf);
68 return blen;
69 }
70
71 p = buf;
72 ret = ceph_crypto_key_decode(key, &p, p + blen);
73 kfree(buf);
74 if (ret)
75 return ret;
76 dout("crypto_key_unarmor key %p type %d len %d\n", key,
77 key->type, key->len);
78 return 0;
79 }
80
81
82
83 #define AES_KEY_SIZE 16
84
ceph_crypto_alloc_cipher(void)85 static struct crypto_blkcipher *ceph_crypto_alloc_cipher(void)
86 {
87 return crypto_alloc_blkcipher("cbc(aes)", 0, CRYPTO_ALG_ASYNC);
88 }
89
90 static const u8 *aes_iv = (u8 *)CEPH_AES_IV;
91
ceph_aes_encrypt(const void * key,int key_len,void * dst,size_t * dst_len,const void * src,size_t src_len)92 static int ceph_aes_encrypt(const void *key, int key_len,
93 void *dst, size_t *dst_len,
94 const void *src, size_t src_len)
95 {
96 struct scatterlist sg_in[2], sg_out[1];
97 struct crypto_blkcipher *tfm = ceph_crypto_alloc_cipher();
98 struct blkcipher_desc desc = { .tfm = tfm, .flags = 0 };
99 int ret;
100 void *iv;
101 int ivsize;
102 size_t zero_padding = (0x10 - (src_len & 0x0f));
103 char pad[16];
104
105 if (IS_ERR(tfm))
106 return PTR_ERR(tfm);
107
108 memset(pad, zero_padding, zero_padding);
109
110 *dst_len = src_len + zero_padding;
111
112 crypto_blkcipher_setkey((void *)tfm, key, key_len);
113 sg_init_table(sg_in, 2);
114 sg_set_buf(&sg_in[0], src, src_len);
115 sg_set_buf(&sg_in[1], pad, zero_padding);
116 sg_init_table(sg_out, 1);
117 sg_set_buf(sg_out, dst, *dst_len);
118 iv = crypto_blkcipher_crt(tfm)->iv;
119 ivsize = crypto_blkcipher_ivsize(tfm);
120
121 memcpy(iv, aes_iv, ivsize);
122 /*
123 print_hex_dump(KERN_ERR, "enc key: ", DUMP_PREFIX_NONE, 16, 1,
124 key, key_len, 1);
125 print_hex_dump(KERN_ERR, "enc src: ", DUMP_PREFIX_NONE, 16, 1,
126 src, src_len, 1);
127 print_hex_dump(KERN_ERR, "enc pad: ", DUMP_PREFIX_NONE, 16, 1,
128 pad, zero_padding, 1);
129 */
130 ret = crypto_blkcipher_encrypt(&desc, sg_out, sg_in,
131 src_len + zero_padding);
132 crypto_free_blkcipher(tfm);
133 if (ret < 0)
134 pr_err("ceph_aes_crypt failed %d\n", ret);
135 /*
136 print_hex_dump(KERN_ERR, "enc out: ", DUMP_PREFIX_NONE, 16, 1,
137 dst, *dst_len, 1);
138 */
139 return 0;
140 }
141
ceph_aes_encrypt2(const void * key,int key_len,void * dst,size_t * dst_len,const void * src1,size_t src1_len,const void * src2,size_t src2_len)142 static int ceph_aes_encrypt2(const void *key, int key_len, void *dst,
143 size_t *dst_len,
144 const void *src1, size_t src1_len,
145 const void *src2, size_t src2_len)
146 {
147 struct scatterlist sg_in[3], sg_out[1];
148 struct crypto_blkcipher *tfm = ceph_crypto_alloc_cipher();
149 struct blkcipher_desc desc = { .tfm = tfm, .flags = 0 };
150 int ret;
151 void *iv;
152 int ivsize;
153 size_t zero_padding = (0x10 - ((src1_len + src2_len) & 0x0f));
154 char pad[16];
155
156 if (IS_ERR(tfm))
157 return PTR_ERR(tfm);
158
159 memset(pad, zero_padding, zero_padding);
160
161 *dst_len = src1_len + src2_len + zero_padding;
162
163 crypto_blkcipher_setkey((void *)tfm, key, key_len);
164 sg_init_table(sg_in, 3);
165 sg_set_buf(&sg_in[0], src1, src1_len);
166 sg_set_buf(&sg_in[1], src2, src2_len);
167 sg_set_buf(&sg_in[2], pad, zero_padding);
168 sg_init_table(sg_out, 1);
169 sg_set_buf(sg_out, dst, *dst_len);
170 iv = crypto_blkcipher_crt(tfm)->iv;
171 ivsize = crypto_blkcipher_ivsize(tfm);
172
173 memcpy(iv, aes_iv, ivsize);
174 /*
175 print_hex_dump(KERN_ERR, "enc key: ", DUMP_PREFIX_NONE, 16, 1,
176 key, key_len, 1);
177 print_hex_dump(KERN_ERR, "enc src1: ", DUMP_PREFIX_NONE, 16, 1,
178 src1, src1_len, 1);
179 print_hex_dump(KERN_ERR, "enc src2: ", DUMP_PREFIX_NONE, 16, 1,
180 src2, src2_len, 1);
181 print_hex_dump(KERN_ERR, "enc pad: ", DUMP_PREFIX_NONE, 16, 1,
182 pad, zero_padding, 1);
183 */
184 ret = crypto_blkcipher_encrypt(&desc, sg_out, sg_in,
185 src1_len + src2_len + zero_padding);
186 crypto_free_blkcipher(tfm);
187 if (ret < 0)
188 pr_err("ceph_aes_crypt2 failed %d\n", ret);
189 /*
190 print_hex_dump(KERN_ERR, "enc out: ", DUMP_PREFIX_NONE, 16, 1,
191 dst, *dst_len, 1);
192 */
193 return 0;
194 }
195
ceph_aes_decrypt(const void * key,int key_len,void * dst,size_t * dst_len,const void * src,size_t src_len)196 static int ceph_aes_decrypt(const void *key, int key_len,
197 void *dst, size_t *dst_len,
198 const void *src, size_t src_len)
199 {
200 struct scatterlist sg_in[1], sg_out[2];
201 struct crypto_blkcipher *tfm = ceph_crypto_alloc_cipher();
202 struct blkcipher_desc desc = { .tfm = tfm };
203 char pad[16];
204 void *iv;
205 int ivsize;
206 int ret;
207 int last_byte;
208
209 if (IS_ERR(tfm))
210 return PTR_ERR(tfm);
211
212 crypto_blkcipher_setkey((void *)tfm, key, key_len);
213 sg_init_table(sg_in, 1);
214 sg_init_table(sg_out, 2);
215 sg_set_buf(sg_in, src, src_len);
216 sg_set_buf(&sg_out[0], dst, *dst_len);
217 sg_set_buf(&sg_out[1], pad, sizeof(pad));
218
219 iv = crypto_blkcipher_crt(tfm)->iv;
220 ivsize = crypto_blkcipher_ivsize(tfm);
221
222 memcpy(iv, aes_iv, ivsize);
223
224 /*
225 print_hex_dump(KERN_ERR, "dec key: ", DUMP_PREFIX_NONE, 16, 1,
226 key, key_len, 1);
227 print_hex_dump(KERN_ERR, "dec in: ", DUMP_PREFIX_NONE, 16, 1,
228 src, src_len, 1);
229 */
230
231 ret = crypto_blkcipher_decrypt(&desc, sg_out, sg_in, src_len);
232 crypto_free_blkcipher(tfm);
233 if (ret < 0) {
234 pr_err("ceph_aes_decrypt failed %d\n", ret);
235 return ret;
236 }
237
238 if (src_len <= *dst_len)
239 last_byte = ((char *)dst)[src_len - 1];
240 else
241 last_byte = pad[src_len - *dst_len - 1];
242 if (last_byte <= 16 && src_len >= last_byte) {
243 *dst_len = src_len - last_byte;
244 } else {
245 pr_err("ceph_aes_decrypt got bad padding %d on src len %d\n",
246 last_byte, (int)src_len);
247 return -EPERM; /* bad padding */
248 }
249 /*
250 print_hex_dump(KERN_ERR, "dec out: ", DUMP_PREFIX_NONE, 16, 1,
251 dst, *dst_len, 1);
252 */
253 return 0;
254 }
255
ceph_aes_decrypt2(const void * key,int key_len,void * dst1,size_t * dst1_len,void * dst2,size_t * dst2_len,const void * src,size_t src_len)256 static int ceph_aes_decrypt2(const void *key, int key_len,
257 void *dst1, size_t *dst1_len,
258 void *dst2, size_t *dst2_len,
259 const void *src, size_t src_len)
260 {
261 struct scatterlist sg_in[1], sg_out[3];
262 struct crypto_blkcipher *tfm = ceph_crypto_alloc_cipher();
263 struct blkcipher_desc desc = { .tfm = tfm };
264 char pad[16];
265 void *iv;
266 int ivsize;
267 int ret;
268 int last_byte;
269
270 if (IS_ERR(tfm))
271 return PTR_ERR(tfm);
272
273 sg_init_table(sg_in, 1);
274 sg_set_buf(sg_in, src, src_len);
275 sg_init_table(sg_out, 3);
276 sg_set_buf(&sg_out[0], dst1, *dst1_len);
277 sg_set_buf(&sg_out[1], dst2, *dst2_len);
278 sg_set_buf(&sg_out[2], pad, sizeof(pad));
279
280 crypto_blkcipher_setkey((void *)tfm, key, key_len);
281 iv = crypto_blkcipher_crt(tfm)->iv;
282 ivsize = crypto_blkcipher_ivsize(tfm);
283
284 memcpy(iv, aes_iv, ivsize);
285
286 /*
287 print_hex_dump(KERN_ERR, "dec key: ", DUMP_PREFIX_NONE, 16, 1,
288 key, key_len, 1);
289 print_hex_dump(KERN_ERR, "dec in: ", DUMP_PREFIX_NONE, 16, 1,
290 src, src_len, 1);
291 */
292
293 ret = crypto_blkcipher_decrypt(&desc, sg_out, sg_in, src_len);
294 crypto_free_blkcipher(tfm);
295 if (ret < 0) {
296 pr_err("ceph_aes_decrypt failed %d\n", ret);
297 return ret;
298 }
299
300 if (src_len <= *dst1_len)
301 last_byte = ((char *)dst1)[src_len - 1];
302 else if (src_len <= *dst1_len + *dst2_len)
303 last_byte = ((char *)dst2)[src_len - *dst1_len - 1];
304 else
305 last_byte = pad[src_len - *dst1_len - *dst2_len - 1];
306 if (last_byte <= 16 && src_len >= last_byte) {
307 src_len -= last_byte;
308 } else {
309 pr_err("ceph_aes_decrypt got bad padding %d on src len %d\n",
310 last_byte, (int)src_len);
311 return -EPERM; /* bad padding */
312 }
313
314 if (src_len < *dst1_len) {
315 *dst1_len = src_len;
316 *dst2_len = 0;
317 } else {
318 *dst2_len = src_len - *dst1_len;
319 }
320 /*
321 print_hex_dump(KERN_ERR, "dec out1: ", DUMP_PREFIX_NONE, 16, 1,
322 dst1, *dst1_len, 1);
323 print_hex_dump(KERN_ERR, "dec out2: ", DUMP_PREFIX_NONE, 16, 1,
324 dst2, *dst2_len, 1);
325 */
326
327 return 0;
328 }
329
330
ceph_decrypt(struct ceph_crypto_key * secret,void * dst,size_t * dst_len,const void * src,size_t src_len)331 int ceph_decrypt(struct ceph_crypto_key *secret, void *dst, size_t *dst_len,
332 const void *src, size_t src_len)
333 {
334 switch (secret->type) {
335 case CEPH_CRYPTO_NONE:
336 if (*dst_len < src_len)
337 return -ERANGE;
338 memcpy(dst, src, src_len);
339 *dst_len = src_len;
340 return 0;
341
342 case CEPH_CRYPTO_AES:
343 return ceph_aes_decrypt(secret->key, secret->len, dst,
344 dst_len, src, src_len);
345
346 default:
347 return -EINVAL;
348 }
349 }
350
ceph_decrypt2(struct ceph_crypto_key * secret,void * dst1,size_t * dst1_len,void * dst2,size_t * dst2_len,const void * src,size_t src_len)351 int ceph_decrypt2(struct ceph_crypto_key *secret,
352 void *dst1, size_t *dst1_len,
353 void *dst2, size_t *dst2_len,
354 const void *src, size_t src_len)
355 {
356 size_t t;
357
358 switch (secret->type) {
359 case CEPH_CRYPTO_NONE:
360 if (*dst1_len + *dst2_len < src_len)
361 return -ERANGE;
362 t = min(*dst1_len, src_len);
363 memcpy(dst1, src, t);
364 *dst1_len = t;
365 src += t;
366 src_len -= t;
367 if (src_len) {
368 t = min(*dst2_len, src_len);
369 memcpy(dst2, src, t);
370 *dst2_len = t;
371 }
372 return 0;
373
374 case CEPH_CRYPTO_AES:
375 return ceph_aes_decrypt2(secret->key, secret->len,
376 dst1, dst1_len, dst2, dst2_len,
377 src, src_len);
378
379 default:
380 return -EINVAL;
381 }
382 }
383
ceph_encrypt(struct ceph_crypto_key * secret,void * dst,size_t * dst_len,const void * src,size_t src_len)384 int ceph_encrypt(struct ceph_crypto_key *secret, void *dst, size_t *dst_len,
385 const void *src, size_t src_len)
386 {
387 switch (secret->type) {
388 case CEPH_CRYPTO_NONE:
389 if (*dst_len < src_len)
390 return -ERANGE;
391 memcpy(dst, src, src_len);
392 *dst_len = src_len;
393 return 0;
394
395 case CEPH_CRYPTO_AES:
396 return ceph_aes_encrypt(secret->key, secret->len, dst,
397 dst_len, src, src_len);
398
399 default:
400 return -EINVAL;
401 }
402 }
403
ceph_encrypt2(struct ceph_crypto_key * secret,void * dst,size_t * dst_len,const void * src1,size_t src1_len,const void * src2,size_t src2_len)404 int ceph_encrypt2(struct ceph_crypto_key *secret, void *dst, size_t *dst_len,
405 const void *src1, size_t src1_len,
406 const void *src2, size_t src2_len)
407 {
408 switch (secret->type) {
409 case CEPH_CRYPTO_NONE:
410 if (*dst_len < src1_len + src2_len)
411 return -ERANGE;
412 memcpy(dst, src1, src1_len);
413 memcpy(dst + src1_len, src2, src2_len);
414 *dst_len = src1_len + src2_len;
415 return 0;
416
417 case CEPH_CRYPTO_AES:
418 return ceph_aes_encrypt2(secret->key, secret->len, dst, dst_len,
419 src1, src1_len, src2, src2_len);
420
421 default:
422 return -EINVAL;
423 }
424 }
425
ceph_key_instantiate(struct key * key,const void * data,size_t datalen)426 int ceph_key_instantiate(struct key *key, const void *data, size_t datalen)
427 {
428 struct ceph_crypto_key *ckey;
429 int ret;
430 void *p;
431
432 ret = -EINVAL;
433 if (datalen <= 0 || datalen > 32767 || !data)
434 goto err;
435
436 ret = key_payload_reserve(key, datalen);
437 if (ret < 0)
438 goto err;
439
440 ret = -ENOMEM;
441 ckey = kmalloc(sizeof(*ckey), GFP_KERNEL);
442 if (!ckey)
443 goto err;
444
445 /* TODO ceph_crypto_key_decode should really take const input */
446 p = (void *)data;
447 ret = ceph_crypto_key_decode(ckey, &p, (char*)data+datalen);
448 if (ret < 0)
449 goto err_ckey;
450
451 key->payload.data = ckey;
452 return 0;
453
454 err_ckey:
455 kfree(ckey);
456 err:
457 return ret;
458 }
459
ceph_key_match(const struct key * key,const void * description)460 int ceph_key_match(const struct key *key, const void *description)
461 {
462 return strcmp(key->description, description) == 0;
463 }
464
ceph_key_destroy(struct key * key)465 void ceph_key_destroy(struct key *key) {
466 struct ceph_crypto_key *ckey = key->payload.data;
467
468 ceph_crypto_key_destroy(ckey);
469 kfree(ckey);
470 }
471
472 struct key_type key_type_ceph = {
473 .name = "ceph",
474 .instantiate = ceph_key_instantiate,
475 .match = ceph_key_match,
476 .destroy = ceph_key_destroy,
477 };
478
ceph_crypto_init(void)479 int ceph_crypto_init(void) {
480 return register_key_type(&key_type_ceph);
481 }
482
ceph_crypto_shutdown(void)483 void ceph_crypto_shutdown(void) {
484 unregister_key_type(&key_type_ceph);
485 }
486