diff options
| author | Richard Levitte <levitte@openssl.org> | 2002-11-12 11:00:25 +0000 |
|---|---|---|
| committer | Richard Levitte <levitte@openssl.org> | 2002-11-12 11:00:25 +0000 |
| commit | 69ce48c3075361d74c96f604031e941a579bab44 (patch) | |
| tree | cb78327122db5b7347c2766142938f31b51dcd6c /crypto/aes/aes_cbc.c | |
| parent | 06b7c8d5baa8be9300b5a038f4d967c06a3a73f9 (diff) | |
Make the CBC mode od AES accept lengths that aren't multiples of 16.
PR: 330
Diffstat (limited to 'crypto/aes/aes_cbc.c')
| -rw-r--r-- | crypto/aes/aes_cbc.c | 26 |
1 files changed, 21 insertions, 5 deletions
diff --git a/crypto/aes/aes_cbc.c b/crypto/aes/aes_cbc.c index 3dfd7aba2a..bf1a808cf0 100644 --- a/crypto/aes/aes_cbc.c +++ b/crypto/aes/aes_cbc.c @@ -62,11 +62,10 @@ void AES_cbc_encrypt(const unsigned char *in, unsigned char *out, unsigned char tmp[16]; assert(in && out && key && ivec); - assert(length % AES_BLOCK_SIZE == 0); assert((AES_ENCRYPT == enc)||(AES_DECRYPT == enc)); - if (AES_ENCRYPT == enc) - while (len > 0) { + if (AES_ENCRYPT == enc) { + while (len >= AES_BLOCK_SIZE) { for(n=0; n < 16; ++n) tmp[n] = in[n] ^ ivec[n]; AES_encrypt(tmp, out, key); @@ -75,8 +74,17 @@ void AES_cbc_encrypt(const unsigned char *in, unsigned char *out, in += 16; out += 16; } - else - while (len > 0) { + if (len) { + for(n=0; n < len; ++n) + tmp[n] = in[n] ^ ivec[n]; + for(n=len; n < AES_BLOCK_SIZE; ++n) + tmp[n] = ivec[n]; + AES_encrypt(tmp, tmp, key); + memcpy(out, tmp, len); + memcpy(ivec, tmp, 16); + } + } else { + while (len >= AES_BLOCK_SIZE) { memcpy(tmp, in, 16); AES_decrypt(in, out, key); for(n=0; n < 16; ++n) @@ -86,4 +94,12 @@ void AES_cbc_encrypt(const unsigned char *in, unsigned char *out, in += 16; out += 16; } + if (len) { + memcpy(tmp, in, 16); + AES_decrypt(tmp, tmp, key); + for(n=0; n < len; ++n) + out[n] ^= ivec[n]; + memcpy(ivec, tmp, 16); + } + } } |