Write WIP test for build_plaintext_padding()ticket18571_029_04_test

3 files changed, 38 insertions, 2 deletions

diff --git a/src/or/hs_descriptor.c b/src/or/hs_descriptor.c
index f58d40eda..760a701fe 100644
--- a/src/or/hs_descriptor.c
+++ b/src/or/hs_descriptor.c
@@ -455,7 +455,7 @@ compute_padding_length(size_t srclen)
   size_t padding_len;
 
   /* Make sure we won't overflow. */
-  tor_assert(srclen > (SIZE_T_CEILING - HS_DESC_PLAINTEXT_PADDING_MULTIPLE));
+  tor_assert(srclen <= (SIZE_T_CEILING - HS_DESC_PLAINTEXT_PADDING_MULTIPLE));
   /* Get the extra length we need to add. For example, if srclen is 234 bytes,
    * this will expand to (2 * 128) == 256 thus an extra 22 bytes. */
   padding_len = CEIL_DIV(srclen, HS_DESC_PLAINTEXT_PADDING_MULTIPLE) *
@@ -468,7 +468,7 @@ compute_padding_length(size_t srclen)
 /* Given a buffer, pad it up to the encrypted section padding requirement. Set
  * the newly allocated string in padded_out and return the length of the
  * padded buffer. */
-static size_t
+STATIC size_t
 build_plaintext_padding(const char *plaintext, size_t plaintext_len,
                         uint8_t **padded_out)
 {
diff --git a/src/or/hs_descriptor.h b/src/or/hs_descriptor.h
index c79b252db..86f60e014 100644
--- a/src/or/hs_descriptor.h
+++ b/src/or/hs_descriptor.h
@@ -192,6 +192,9 @@ STATIC char *encode_link_specifiers(const smartlist_t *specs);
 STATIC smartlist_t *decode_link_specifiers(const char *encoded);
 STATIC hs_desc_intro_point_t *decode_introduction_point(const char *text,
                                                         const char *end);
+STATIC size_t build_plaintext_padding(const char *plaintext,
+                                      size_t plaintext_len,
+                                      uint8_t **padded_out);
 
 #endif /* HS_DESCRIPTOR_PRIVATE */
 
diff --git a/src/test/test_hs_descriptor.c b/src/test/test_hs_descriptor.c
index 12a84562d..6834cc476 100644
--- a/src/test/test_hs_descriptor.c
+++ b/src/test/test_hs_descriptor.c
@@ -259,6 +259,36 @@ test_cert_encoding(void *arg)
   free(encoded);
 }
 
+/* Test the descriptor padding. */
+static void
+test_descriptor_padding(void *arg)
+{
+  char *plaintext;
+  size_t plaintext_len, padded_len;
+  uint8_t *padded_plaintext;
+
+  (void) arg;
+
+  { /* test #1: no padding */
+    plaintext_len = 128;
+    plaintext = tor_malloc(plaintext_len);
+    padded_len = build_plaintext_padding(plaintext, plaintext_len, &padded_plaintext);
+    tt_int_op(padded_len, ==, plaintext_len);
+    tor_free(plaintext);
+  }
+
+  { /* test #1: one byte padding? */
+    plaintext_len = 127;
+    plaintext = tor_malloc(plaintext_len);
+    padded_len = build_plaintext_padding(plaintext, plaintext_len, &padded_plaintext);
+    tt_int_op(padded_len, ==, 128);
+    tor_free(plaintext);
+  }
+
+
+ done: ;
+}
+
 static void
 test_link_specifier(void *arg)
 {
@@ -388,6 +418,9 @@ struct testcase_t hs_descriptor[] = {
     NULL, NULL },
   { "decode_descriptor", test_decode_descriptor, TT_FORK,
     NULL, NULL },
+  { "descriptor_padding", test_descriptor_padding, TT_FORK,
+    NULL, NULL },
+
 
   END_OF_TESTCASES
 };