fs/ceph/crypto.c

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