Add zero padding

include/polarssl/cipher.h

@@ -108,6 +108,7 @@ typedef enum {
     POLARSSL_PADDING_PKCS7 = 0,     /**< PKCS7 padding (default)        */
     POLARSSL_PADDING_ONE_AND_ZEROS, /**< ISO/IEC 7816-4 padding         */
     POLARSSL_PADDING_ZEROS_AND_LEN, /**< ANSI X.923 padding             */
+    POLARSSL_PADDING_ZEROS,         /**< zero padding (not reversible!) */
 } cipher_padding_t;
 
 typedef enum {

library/cipher.c

@@ -630,6 +630,33 @@ static int get_zeros_and_len_padding( unsigned char *input, size_t input_len,
     return 0;
 }
 
+/*
+ * Zero padding: fill with 00 ... 00
+ */
+static void add_zeros_padding( unsigned char *output,
+                               size_t output_len, size_t data_len )
+{
+    unsigned char i;
+
+    for( i = data_len; i < output_len; i++ )
+        output[i] = 0x00;
+}
+
+static int get_zeros_padding( unsigned char *input, size_t input_len,
+                              size_t *data_len )
+{
+    unsigned char *p = input + input_len - 1;
+    if( NULL == input || NULL == data_len )
+        return POLARSSL_ERR_CIPHER_BAD_INPUT_DATA;
+
+    while( *p == 0x00 && p > input )
+        --p;
+
+    *data_len = *p == 0x00 ? 0 : p - input + 1;
+
+    return 0;
+}
+
 int cipher_finish( cipher_context_t *ctx, unsigned char *output, size_t *olen)
 {
     int ret = 0;
@@ -709,6 +736,13 @@ int cipher_set_padding_mode( cipher_context_t *ctx, cipher_padding_t mode )
         return 0;
     }
 
+    if( POLARSSL_PADDING_ZEROS == mode )
+    {
+        ctx->add_padding = add_zeros_padding;
+        ctx->get_padding = get_zeros_padding;
+        return 0;
+    }
+
     return POLARSSL_ERR_CIPHER_BAD_INPUT_DATA;
 }
 

tests/suites/test_suite_cipher.aes.data

@@ -185,6 +185,66 @@ AES Encrypt and decrypt 49 bytes with zeros and len padding
 depends_on:POLARSSL_AES_C
 enc_dec_buf:POLARSSL_CIPHER_AES_128_CBC:AES-128-CBC:128:49:POLARSSL_PADDING_ZEROS_AND_LEN
 
+AES Encrypt and decrypt 0 bytes with zeros padding
+depends_on:POLARSSL_AES_C
+enc_dec_buf:POLARSSL_CIPHER_AES_128_CBC:AES-128-CBC:128:0:POLARSSL_PADDING_ZEROS
+
+AES Encrypt and decrypt 1 byte with zeros padding
+depends_on:POLARSSL_AES_C
+enc_dec_buf:POLARSSL_CIPHER_AES_128_CBC:AES-128-CBC:128:1:POLARSSL_PADDING_ZEROS
+
+AES Encrypt and decrypt 2 bytes with zeros padding
+depends_on:POLARSSL_AES_C
+enc_dec_buf:POLARSSL_CIPHER_AES_128_CBC:AES-128-CBC:128:2:POLARSSL_PADDING_ZEROS
+
+AES Encrypt and decrypt 7 bytes with zeros padding
+depends_on:POLARSSL_AES_C
+enc_dec_buf:POLARSSL_CIPHER_AES_128_CBC:AES-128-CBC:128:7:POLARSSL_PADDING_ZEROS
+
+AES Encrypt and decrypt 8 bytes with zeros padding
+depends_on:POLARSSL_AES_C
+enc_dec_buf:POLARSSL_CIPHER_AES_128_CBC:AES-128-CBC:128:8:POLARSSL_PADDING_ZEROS
+
+AES Encrypt and decrypt 9 bytes with zeros padding
+depends_on:POLARSSL_AES_C
+enc_dec_buf:POLARSSL_CIPHER_AES_128_CBC:AES-128-CBC:128:9:POLARSSL_PADDING_ZEROS
+
+AES Encrypt and decrypt 15 bytes with zeros padding
+depends_on:POLARSSL_AES_C
+enc_dec_buf:POLARSSL_CIPHER_AES_128_CBC:AES-128-CBC:128:15:POLARSSL_PADDING_ZEROS
+
+AES Encrypt and decrypt 16 bytes with zeros padding
+depends_on:POLARSSL_AES_C
+enc_dec_buf:POLARSSL_CIPHER_AES_128_CBC:AES-128-CBC:128:16:POLARSSL_PADDING_ZEROS
+
+AES Encrypt and decrypt 17 bytes with zeros padding
+depends_on:POLARSSL_AES_C
+enc_dec_buf:POLARSSL_CIPHER_AES_128_CBC:AES-128-CBC:128:17:POLARSSL_PADDING_ZEROS
+
+AES Encrypt and decrypt 31 bytes with zeros padding
+depends_on:POLARSSL_AES_C
+enc_dec_buf:POLARSSL_CIPHER_AES_128_CBC:AES-128-CBC:128:31:POLARSSL_PADDING_ZEROS
+
+AES Encrypt and decrypt 32 bytes with zeros padding
+depends_on:POLARSSL_AES_C
+enc_dec_buf:POLARSSL_CIPHER_AES_128_CBC:AES-128-CBC:128:32:POLARSSL_PADDING_ZEROS
+
+AES Encrypt and decrypt 33 bytes with zeros padding
+depends_on:POLARSSL_AES_C
+enc_dec_buf:POLARSSL_CIPHER_AES_128_CBC:AES-128-CBC:128:33:POLARSSL_PADDING_ZEROS
+
+AES Encrypt and decrypt 47 bytes with zeros padding
+depends_on:POLARSSL_AES_C
+enc_dec_buf:POLARSSL_CIPHER_AES_128_CBC:AES-128-CBC:128:47:POLARSSL_PADDING_ZEROS
+
+AES Encrypt and decrypt 48 bytes with zeros padding
+depends_on:POLARSSL_AES_C
+enc_dec_buf:POLARSSL_CIPHER_AES_128_CBC:AES-128-CBC:128:48:POLARSSL_PADDING_ZEROS
+
+AES Encrypt and decrypt 49 bytes with zeros padding
+depends_on:POLARSSL_AES_C
+enc_dec_buf:POLARSSL_CIPHER_AES_128_CBC:AES-128-CBC:128:49:POLARSSL_PADDING_ZEROS
+
 AES Encrypt and decrypt 0 bytes in multiple parts
 depends_on:POLARSSL_AES_C
 enc_dec_buf_multipart:POLARSSL_CIPHER_AES_128_CBC:128:0:0:

tests/suites/test_suite_cipher.blowfish.data

@@ -185,6 +185,66 @@ BLOWFISH Encrypt and decrypt 49 bytes with zeros and len padding
 depends_on:POLARSSL_BLOWFISH_C
 enc_dec_buf:POLARSSL_CIPHER_BLOWFISH_CBC:BLOWFISH-CBC:128:49:POLARSSL_PADDING_ZEROS_AND_LEN
 
+BLOWFISH Encrypt and decrypt 0 bytes with zeros padding
+depends_on:POLARSSL_BLOWFISH_C
+enc_dec_buf:POLARSSL_CIPHER_BLOWFISH_CBC:BLOWFISH-CBC:128:0:POLARSSL_PADDING_ZEROS
+
+BLOWFISH Encrypt and decrypt 1 byte with zeros padding
+depends_on:POLARSSL_BLOWFISH_C
+enc_dec_buf:POLARSSL_CIPHER_BLOWFISH_CBC:BLOWFISH-CBC:128:1:POLARSSL_PADDING_ZEROS
+
+BLOWFISH Encrypt and decrypt 2 bytes with zeros padding
+depends_on:POLARSSL_BLOWFISH_C
+enc_dec_buf:POLARSSL_CIPHER_BLOWFISH_CBC:BLOWFISH-CBC:128:2:POLARSSL_PADDING_ZEROS
+
+BLOWFISH Encrypt and decrypt 7 bytes with zeros padding
+depends_on:POLARSSL_BLOWFISH_C
+enc_dec_buf:POLARSSL_CIPHER_BLOWFISH_CBC:BLOWFISH-CBC:128:7:POLARSSL_PADDING_ZEROS
+
+BLOWFISH Encrypt and decrypt 8 bytes with zeros padding
+depends_on:POLARSSL_BLOWFISH_C
+enc_dec_buf:POLARSSL_CIPHER_BLOWFISH_CBC:BLOWFISH-CBC:128:8:POLARSSL_PADDING_ZEROS
+
+BLOWFISH Encrypt and decrypt 9 bytes with zeros padding
+depends_on:POLARSSL_BLOWFISH_C
+enc_dec_buf:POLARSSL_CIPHER_BLOWFISH_CBC:BLOWFISH-CBC:128:9:POLARSSL_PADDING_ZEROS
+
+BLOWFISH Encrypt and decrypt 15 bytes with zeros padding
+depends_on:POLARSSL_BLOWFISH_C
+enc_dec_buf:POLARSSL_CIPHER_BLOWFISH_CBC:BLOWFISH-CBC:128:15:POLARSSL_PADDING_ZEROS
+
+BLOWFISH Encrypt and decrypt 16 bytes with zeros padding
+depends_on:POLARSSL_BLOWFISH_C
+enc_dec_buf:POLARSSL_CIPHER_BLOWFISH_CBC:BLOWFISH-CBC:128:16:POLARSSL_PADDING_ZEROS
+
+BLOWFISH Encrypt and decrypt 17 bytes with zeros padding
+depends_on:POLARSSL_BLOWFISH_C
+enc_dec_buf:POLARSSL_CIPHER_BLOWFISH_CBC:BLOWFISH-CBC:128:17:POLARSSL_PADDING_ZEROS
+
+BLOWFISH Encrypt and decrypt 31 bytes with zeros padding
+depends_on:POLARSSL_BLOWFISH_C
+enc_dec_buf:POLARSSL_CIPHER_BLOWFISH_CBC:BLOWFISH-CBC:128:31:POLARSSL_PADDING_ZEROS
+
+BLOWFISH Encrypt and decrypt 32 bytes with zeros padding
+depends_on:POLARSSL_BLOWFISH_C
+enc_dec_buf:POLARSSL_CIPHER_BLOWFISH_CBC:BLOWFISH-CBC:128:32:POLARSSL_PADDING_ZEROS
+
+BLOWFISH Encrypt and decrypt 32 bytes with zeros padding
+depends_on:POLARSSL_BLOWFISH_C
+enc_dec_buf:POLARSSL_CIPHER_BLOWFISH_CBC:BLOWFISH-CBC:128:33:POLARSSL_PADDING_ZEROS
+
+BLOWFISH Encrypt and decrypt 47 bytes with zeros padding
+depends_on:POLARSSL_BLOWFISH_C
+enc_dec_buf:POLARSSL_CIPHER_BLOWFISH_CBC:BLOWFISH-CBC:128:47:POLARSSL_PADDING_ZEROS
+
+BLOWFISH Encrypt and decrypt 48 bytes with zeros padding
+depends_on:POLARSSL_BLOWFISH_C
+enc_dec_buf:POLARSSL_CIPHER_BLOWFISH_CBC:BLOWFISH-CBC:128:48:POLARSSL_PADDING_ZEROS
+
+BLOWFISH Encrypt and decrypt 49 bytes with zeros padding
+depends_on:POLARSSL_BLOWFISH_C
+enc_dec_buf:POLARSSL_CIPHER_BLOWFISH_CBC:BLOWFISH-CBC:128:49:POLARSSL_PADDING_ZEROS
+
 BLOWFISH Encrypt and decrypt 0 bytes in multiple parts
 depends_on:POLARSSL_BLOWFISH_C
 enc_dec_buf_multipart:POLARSSL_CIPHER_BLOWFISH_CBC:128:0:0:

tests/suites/test_suite_cipher.camellia.data

@@ -185,6 +185,66 @@ CAMELLIA Encrypt and decrypt 49 bytes with zeros and len padding
 depends_on:POLARSSL_CAMELLIA_C
 enc_dec_buf:POLARSSL_CIPHER_CAMELLIA_128_CBC:CAMELLIA-128-CBC:128:49:POLARSSL_PADDING_ZEROS_AND_LEN
 
+CAMELLIA Encrypt and decrypt 0 bytes with zeros padding
+depends_on:POLARSSL_CAMELLIA_C
+enc_dec_buf:POLARSSL_CIPHER_CAMELLIA_128_CBC:CAMELLIA-128-CBC:128:0:POLARSSL_PADDING_ZEROS
+
+CAMELLIA Encrypt and decrypt 1 byte with zeros padding
+depends_on:POLARSSL_CAMELLIA_C
+enc_dec_buf:POLARSSL_CIPHER_CAMELLIA_128_CBC:CAMELLIA-128-CBC:128:1:POLARSSL_PADDING_ZEROS
+
+CAMELLIA Encrypt and decrypt 2 bytes with zeros padding
+depends_on:POLARSSL_CAMELLIA_C
+enc_dec_buf:POLARSSL_CIPHER_CAMELLIA_128_CBC:CAMELLIA-128-CBC:128:2:POLARSSL_PADDING_ZEROS
+
+CAMELLIA Encrypt and decrypt 7 bytes with zeros padding
+depends_on:POLARSSL_CAMELLIA_C
+enc_dec_buf:POLARSSL_CIPHER_CAMELLIA_128_CBC:CAMELLIA-128-CBC:128:7:POLARSSL_PADDING_ZEROS
+
+CAMELLIA Encrypt and decrypt 8 bytes with zeros padding
+depends_on:POLARSSL_CAMELLIA_C
+enc_dec_buf:POLARSSL_CIPHER_CAMELLIA_128_CBC:CAMELLIA-128-CBC:128:8:POLARSSL_PADDING_ZEROS
+
+CAMELLIA Encrypt and decrypt 9 bytes with zeros padding
+depends_on:POLARSSL_CAMELLIA_C
+enc_dec_buf:POLARSSL_CIPHER_CAMELLIA_128_CBC:CAMELLIA-128-CBC:128:9:POLARSSL_PADDING_ZEROS
+
+CAMELLIA Encrypt and decrypt 15 bytes with zeros padding
+depends_on:POLARSSL_CAMELLIA_C
+enc_dec_buf:POLARSSL_CIPHER_CAMELLIA_128_CBC:CAMELLIA-128-CBC:128:15:POLARSSL_PADDING_ZEROS
+
+CAMELLIA Encrypt and decrypt 16 bytes with zeros padding
+depends_on:POLARSSL_CAMELLIA_C
+enc_dec_buf:POLARSSL_CIPHER_CAMELLIA_128_CBC:CAMELLIA-128-CBC:128:16:POLARSSL_PADDING_ZEROS
+
+CAMELLIA Encrypt and decrypt 17 bytes with zeros padding
+depends_on:POLARSSL_CAMELLIA_C
+enc_dec_buf:POLARSSL_CIPHER_CAMELLIA_128_CBC:CAMELLIA-128-CBC:128:17:POLARSSL_PADDING_ZEROS
+
+CAMELLIA Encrypt and decrypt 31 bytes with zeros padding
+depends_on:POLARSSL_CAMELLIA_C
+enc_dec_buf:POLARSSL_CIPHER_CAMELLIA_128_CBC:CAMELLIA-128-CBC:128:31:POLARSSL_PADDING_ZEROS
+
+CAMELLIA Encrypt and decrypt 32 bytes with zeros padding
+depends_on:POLARSSL_CAMELLIA_C
+enc_dec_buf:POLARSSL_CIPHER_CAMELLIA_128_CBC:CAMELLIA-128-CBC:128:32:POLARSSL_PADDING_ZEROS
+
+CAMELLIA Encrypt and decrypt 32 bytes with zeros padding
+depends_on:POLARSSL_CAMELLIA_C
+enc_dec_buf:POLARSSL_CIPHER_CAMELLIA_128_CBC:CAMELLIA-128-CBC:128:33:POLARSSL_PADDING_ZEROS
+
+CAMELLIA Encrypt and decrypt 47 bytes with zeros padding
+depends_on:POLARSSL_CAMELLIA_C
+enc_dec_buf:POLARSSL_CIPHER_CAMELLIA_128_CBC:CAMELLIA-128-CBC:128:47:POLARSSL_PADDING_ZEROS
+
+CAMELLIA Encrypt and decrypt 48 bytes with zeros padding
+depends_on:POLARSSL_CAMELLIA_C
+enc_dec_buf:POLARSSL_CIPHER_CAMELLIA_128_CBC:CAMELLIA-128-CBC:128:48:POLARSSL_PADDING_ZEROS
+
+CAMELLIA Encrypt and decrypt 49 bytes with zeros padding
+depends_on:POLARSSL_CAMELLIA_C
+enc_dec_buf:POLARSSL_CIPHER_CAMELLIA_128_CBC:CAMELLIA-128-CBC:128:49:POLARSSL_PADDING_ZEROS
+
 CAMELLIA Encrypt and decrypt 0 bytes in multiple parts
 depends_on:POLARSSL_CAMELLIA_C
 enc_dec_buf_multipart:POLARSSL_CIPHER_CAMELLIA_128_CBC:128:0:0:

tests/suites/test_suite_cipher.des.data

@@ -185,6 +185,66 @@ DES Encrypt and decrypt 49 bytes with zeros and len padding
 depends_on:POLARSSL_DES_C
 enc_dec_buf:POLARSSL_CIPHER_DES_CBC:DES-CBC:56:49:POLARSSL_PADDING_ZEROS_AND_LEN
 
+DES Encrypt and decrypt 0 bytes with zeros padding
+depends_on:POLARSSL_DES_C
+enc_dec_buf:POLARSSL_CIPHER_DES_CBC:DES-CBC:56:0:POLARSSL_PADDING_ZEROS
+
+DES Encrypt and decrypt 1 byte with zeros padding
+depends_on:POLARSSL_DES_C
+enc_dec_buf:POLARSSL_CIPHER_DES_CBC:DES-CBC:56:1:POLARSSL_PADDING_ZEROS
+
+DES Encrypt and decrypt 2 bytes with zeros padding
+depends_on:POLARSSL_DES_C
+enc_dec_buf:POLARSSL_CIPHER_DES_CBC:DES-CBC:56:2:POLARSSL_PADDING_ZEROS
+
+DES Encrypt and decrypt 7 bytes with zeros padding
+depends_on:POLARSSL_DES_C
+enc_dec_buf:POLARSSL_CIPHER_DES_CBC:DES-CBC:56:7:POLARSSL_PADDING_ZEROS
+
+DES Encrypt and decrypt 8 bytes with zeros padding
+depends_on:POLARSSL_DES_C
+enc_dec_buf:POLARSSL_CIPHER_DES_CBC:DES-CBC:56:8:POLARSSL_PADDING_ZEROS
+
+DES Encrypt and decrypt 9 bytes with zeros padding
+depends_on:POLARSSL_DES_C
+enc_dec_buf:POLARSSL_CIPHER_DES_CBC:DES-CBC:56:9:POLARSSL_PADDING_ZEROS
+
+DES Encrypt and decrypt 15 bytes with zeros padding
+depends_on:POLARSSL_DES_C
+enc_dec_buf:POLARSSL_CIPHER_DES_CBC:DES-CBC:56:15:POLARSSL_PADDING_ZEROS
+
+DES Encrypt and decrypt 16 bytes with zeros padding
+depends_on:POLARSSL_DES_C
+enc_dec_buf:POLARSSL_CIPHER_DES_CBC:DES-CBC:56:16:POLARSSL_PADDING_ZEROS
+
+DES Encrypt and decrypt 17 bytes with zeros padding
+depends_on:POLARSSL_DES_C
+enc_dec_buf:POLARSSL_CIPHER_DES_CBC:DES-CBC:56:17:POLARSSL_PADDING_ZEROS
+
+DES Encrypt and decrypt 31 bytes with zeros padding
+depends_on:POLARSSL_DES_C
+enc_dec_buf:POLARSSL_CIPHER_DES_CBC:DES-CBC:56:31:POLARSSL_PADDING_ZEROS
+
+DES Encrypt and decrypt 32 bytes with zeros padding
+depends_on:POLARSSL_DES_C
+enc_dec_buf:POLARSSL_CIPHER_DES_CBC:DES-CBC:56:32:POLARSSL_PADDING_ZEROS
+
+DES Encrypt and decrypt 32 bytes with zeros padding
+depends_on:POLARSSL_DES_C
+enc_dec_buf:POLARSSL_CIPHER_DES_CBC:DES-CBC:56:33:POLARSSL_PADDING_ZEROS
+
+DES Encrypt and decrypt 47 bytes with zeros padding
+depends_on:POLARSSL_DES_C
+enc_dec_buf:POLARSSL_CIPHER_DES_CBC:DES-CBC:56:47:POLARSSL_PADDING_ZEROS
+
+DES Encrypt and decrypt 48 bytes with zeros padding
+depends_on:POLARSSL_DES_C
+enc_dec_buf:POLARSSL_CIPHER_DES_CBC:DES-CBC:56:48:POLARSSL_PADDING_ZEROS
+
+DES Encrypt and decrypt 49 bytes with zeros padding
+depends_on:POLARSSL_DES_C
+enc_dec_buf:POLARSSL_CIPHER_DES_CBC:DES-CBC:56:49:POLARSSL_PADDING_ZEROS
+
 DES Encrypt and decrypt 0 bytes in multiple parts
 depends_on:POLARSSL_DES_C
 enc_dec_buf_multipart:POLARSSL_CIPHER_DES_CBC:56:0:0:

tests/suites/test_suite_cipher.padding.data

@@ -120,3 +120,24 @@ check_padding:POLARSSL_PADDING_ZEROS_AND_LEN:"000004":POLARSSL_ERR_CIPHER_INVALI
 
 Check zeros and len padding #6 (not enough zeros)
 check_padding:POLARSSL_PADDING_ZEROS_AND_LEN:"DABBAD000004":POLARSSL_ERR_CIPHER_INVALID_PADDING:0
+
+Check zeros padding #1 (correct)
+check_padding:POLARSSL_PADDING_ZEROS:"DABBAD00":0:3
+
+Check zeros padding #2 (correct)
+check_padding:POLARSSL_PADDING_ZEROS:"DABBAD0000":0:3
+
+Check zeros padding #3 (correct)
+check_padding:POLARSSL_PADDING_ZEROS:"DABBAD":0:3
+
+Check zeros padding #4 (correct)
+check_padding:POLARSSL_PADDING_ZEROS:"000000":0:0
+
+Check no padding #1 (correct by definition)
+check_padding:POLARSSL_PADDING_NONE:"DABBAD00":0:4
+
+Check no padding #2 (correct by definition)
+check_padding:POLARSSL_PADDING_NONE:"DABBAD0001":0:5
+
+Check no padding #3 (correct by definition)
+check_padding:POLARSSL_PADDING_NONE:"":0:0