Commit 61f318b1 authored by George Kadianakis's avatar George Kadianakis
Browse files

prop224: Rename padding size def to something less confusing. 

People felt it could refer to the descriptor header section instead of
the plaintext of the superencrypted section.
parent e6b03151

src/or/hs_descriptor.c

+6 −7
Original line number Diff line number Diff line
@@ -558,18 +558,17 @@ static size_t 
compute_padded_plaintext_length(size_t plaintext_len)

{

  size_t plaintext_padded_len;

  const int padding_block_length = HS_DESC_SUPERENC_PLAINTEXT_PAD_MULTIPLE;



  /* Make sure we won't overflow. */

  tor_assert(plaintext_len <=

             (SIZE_T_CEILING - HS_DESC_PLAINTEXT_PADDING_MULTIPLE));

  tor_assert(plaintext_len <= (SIZE_T_CEILING - padding_block_length));



  /* Get the extra length we need to add. For example, if srclen is 10200

   * bytes, this will expand to (2 * 10k) == 20k thus an extra 9800 bytes. */

  plaintext_padded_len = CEIL_DIV(plaintext_len,

                                  HS_DESC_PLAINTEXT_PADDING_MULTIPLE) *

                         HS_DESC_PLAINTEXT_PADDING_MULTIPLE;

  plaintext_padded_len = CEIL_DIV(plaintext_len, padding_block_length) *

                         padding_block_length;

  /* Can never be extra careful. Make sure we are _really_ padded. */

  tor_assert(!(plaintext_padded_len % HS_DESC_PLAINTEXT_PADDING_MULTIPLE));

  tor_assert(!(plaintext_padded_len % padding_block_length));

  return plaintext_padded_len;

}
@@ -619,7 +618,7 @@ build_encrypted(const uint8_t *key, const uint8_t *iv, const char *plaintext, 
    encrypted_len = build_plaintext_padding(plaintext, plaintext_len,

                                            &padded_plaintext);

    /* Extra precautions that we have a valid padding length. */

    tor_assert(!(encrypted_len % HS_DESC_PLAINTEXT_PADDING_MULTIPLE));

    tor_assert(!(encrypted_len % HS_DESC_SUPERENC_PLAINTEXT_PAD_MULTIPLE));

  } else { /* No padding required for inner layers */

    padded_plaintext = tor_memdup(plaintext, plaintext_len);

    encrypted_len = plaintext_len;

src/test/test_hs_descriptor.c

+5 −5
Original line number Diff line number Diff line
@@ -317,13 +317,13 @@ test_descriptor_padding(void *arg) 
/* Example: if l = 129, the ceiled division gives 2 and then multiplied by 128

 * to give 256. With l = 127, ceiled division gives 1 then times 128. */

#define PADDING_EXPECTED_LEN(l) \

  CEIL_DIV(l, HS_DESC_PLAINTEXT_PADDING_MULTIPLE) * \

  HS_DESC_PLAINTEXT_PADDING_MULTIPLE

  CEIL_DIV(l, HS_DESC_SUPERENC_PLAINTEXT_PAD_MULTIPLE) * \

  HS_DESC_SUPERENC_PLAINTEXT_PAD_MULTIPLE



  (void) arg;



  { /* test #1: no padding */

    plaintext_len = HS_DESC_PLAINTEXT_PADDING_MULTIPLE;

    plaintext_len = HS_DESC_SUPERENC_PLAINTEXT_PAD_MULTIPLE;

    plaintext = tor_malloc(plaintext_len);

    padded_len = build_plaintext_padding(plaintext, plaintext_len,

                                         &padded_plaintext);
@@ -339,7 +339,7 @@ test_descriptor_padding(void *arg) 
  }



  { /* test #2: one byte padding? */

    plaintext_len = HS_DESC_PLAINTEXT_PADDING_MULTIPLE - 1;

    plaintext_len = HS_DESC_SUPERENC_PLAINTEXT_PAD_MULTIPLE - 1;

    plaintext = tor_malloc(plaintext_len);

    padded_plaintext = NULL;

    padded_len = build_plaintext_padding(plaintext, plaintext_len,
@@ -356,7 +356,7 @@ test_descriptor_padding(void *arg) 
  }



  { /* test #3: Lots more bytes of padding? */

    plaintext_len = HS_DESC_PLAINTEXT_PADDING_MULTIPLE + 1;

    plaintext_len = HS_DESC_SUPERENC_PLAINTEXT_PAD_MULTIPLE + 1;

    plaintext = tor_malloc(plaintext_len);

    padded_plaintext = NULL;

    padded_len = build_plaintext_padding(plaintext, plaintext_len,