Commit 915e8561d559abba1b81934e31e54a3f850fa7bf
Committed by
David S. Miller
David S. Miller
1 parent
fbdae9f3e7
Exists in
master
and in
7 other branches
[CRYPTO] Handle unaligned iv from encrypt_iv/decrypt_iv
Even though cit_iv is now always aligned, the user can still supply an unaligned iv through crypto_cipher_encrypt_iv/crypto_cipher_decrypt_iv. This patch will check the alignment of the user-supplied iv and copy it if necessary. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Showing 1 changed file with 27 additions and 2 deletions Side-by-side Diff
crypto/cipher.c
| ... | ... | @@ -154,6 +154,31 @@ |
| 154 | 154 | return 0; |
| 155 | 155 | } |
| 156 | 156 | |
| 157 | +static int crypt_iv_unaligned(struct cipher_desc *desc, | |
| 158 | + struct scatterlist *dst, | |
| 159 | + struct scatterlist *src, | |
| 160 | + unsigned int nbytes) | |
| 161 | +{ | |
| 162 | + struct crypto_tfm *tfm = desc->tfm; | |
| 163 | + unsigned int alignmask = crypto_tfm_alg_alignmask(tfm); | |
| 164 | + u8 *iv = desc->info; | |
| 165 | + | |
| 166 | + if (unlikely(((unsigned long)iv & alignmask))) { | |
| 167 | + unsigned int ivsize = tfm->crt_cipher.cit_ivsize; | |
| 168 | + u8 buffer[ivsize + alignmask]; | |
| 169 | + u8 *tmp = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); | |
| 170 | + int err; | |
| 171 | + | |
| 172 | + desc->info = memcpy(tmp, iv, ivsize); | |
| 173 | + err = crypt(desc, dst, src, nbytes); | |
| 174 | + memcpy(iv, tmp, ivsize); | |
| 175 | + | |
| 176 | + return err; | |
| 177 | + } | |
| 178 | + | |
| 179 | + return crypt(desc, dst, src, nbytes); | |
| 180 | +} | |
| 181 | + | |
| 157 | 182 | static unsigned int cbc_process_encrypt(const struct cipher_desc *desc, |
| 158 | 183 | u8 *dst, const u8 *src, |
| 159 | 184 | unsigned int nbytes) |
| ... | ... | @@ -298,7 +323,7 @@ |
| 298 | 323 | desc.prfn = cipher->cia_encrypt_cbc ?: cbc_process_encrypt; |
| 299 | 324 | desc.info = iv; |
| 300 | 325 | |
| 301 | - return crypt(&desc, dst, src, nbytes); | |
| 326 | + return crypt_iv_unaligned(&desc, dst, src, nbytes); | |
| 302 | 327 | } |
| 303 | 328 | |
| 304 | 329 | static int cbc_decrypt(struct crypto_tfm *tfm, |
| ... | ... | @@ -330,7 +355,7 @@ |
| 330 | 355 | desc.prfn = cipher->cia_decrypt_cbc ?: cbc_process_decrypt; |
| 331 | 356 | desc.info = iv; |
| 332 | 357 | |
| 333 | - return crypt(&desc, dst, src, nbytes); | |
| 358 | + return crypt_iv_unaligned(&desc, dst, src, nbytes); | |
| 334 | 359 | } |
| 335 | 360 | |
| 336 | 361 | static int nocrypt(struct crypto_tfm *tfm, |