docs + fix bug with zero expansion on boundary

awslabs · Jan 24, 2025 · e42d572 · e42d572
1 parent 86c67e1
commit e42d572
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Showing 2 changed files with 7 additions and 2 deletions.
diff --git a/source/host_utils.c b/source/host_utils.c
@@ -65,6 +65,8 @@ static struct aws_byte_cursor s_percent_uri_enc = AWS_BYTE_CUR_INIT_FROM_STRING_
  * ipv6 can be embedded in url, in which case % must be uri encoded as %25.
  * Implementation is fairly trivial and just iterates through the string
  * keeping track of the spec above.
+ * Note: there is no single rfc for IPv6 address - base format defined in RFC 5952, 
+ * zoneId and uri extensions defined in RFC 6874 and RFC 3986
  */
 bool aws_host_utils_is_ipv6(struct aws_byte_cursor host, bool is_uri_encoded) {
     if (host.len == 0) {
@@ -99,13 +101,15 @@ bool aws_host_utils_is_ipv6(struct aws_byte_cursor host, bool is_uri_encoded) {
                     return false;
                 }
                 has_double_colon = true;
+                --group_count; /* avoid double counting groups */
             }
         } else {
             ++digit_count;
         }
 
         if (digit_count > 4 || /* too many digits in group */
             group_count > 8) { /* too many groups */
+            AWS_LOGF_DEBUG(0, "here %d", group_count);
             return false;
         }
     }
@@ -121,5 +125,5 @@ bool aws_host_utils_is_ipv6(struct aws_byte_cursor host, bool is_uri_encoded) {
         }
     }
 
-    return has_double_colon ? group_count <= 7 : group_count == 8;
+    return has_double_colon ? group_count <= 8 : group_count == 8;
 }
diff --git a/tests/host_util_test.c b/tests/host_util_test.c
@@ -51,6 +51,8 @@ static int s_test_is_ipv6(struct aws_allocator *allocator, void *ctx) {
     ASSERT_TRUE(aws_host_utils_is_ipv6(aws_byte_cursor_from_c_str("fe80::1%25en0"), true));
     ASSERT_TRUE(aws_host_utils_is_ipv6(aws_byte_cursor_from_c_str("2001:db8:85a3:8d3:1319:8a2e:370:7348"), true));
     ASSERT_TRUE(aws_host_utils_is_ipv6(aws_byte_cursor_from_c_str("2001::"), false));
+    ASSERT_TRUE(aws_host_utils_is_ipv6(aws_byte_cursor_from_c_str("1:2:3:4:5:6:7::"), false));
+    ASSERT_TRUE(aws_host_utils_is_ipv6(aws_byte_cursor_from_c_str("::1:2:3:4:5:6:7"), false));
 
     ASSERT_TRUE(aws_host_utils_is_ipv6(aws_byte_cursor_from_c_str("2001:DB8:85A3::8A2E:370:7334"), false));
     ASSERT_TRUE(aws_host_utils_is_ipv6(aws_byte_cursor_from_c_str("2001:0db8:85a3:0000:0000:8a2e:0370:7334"), false));
@@ -71,7 +73,6 @@ static int s_test_is_ipv6(struct aws_allocator *allocator, void *ctx) {
     ASSERT_FALSE(
         aws_host_utils_is_ipv6(aws_byte_cursor_from_c_str("z001:0db8:0000:0000:0000:8a2e:0370:7334:8745"), false));
     ASSERT_FALSE(aws_host_utils_is_ipv6(aws_byte_cursor_from_c_str("z001::8a2e::8745"), false));
-    ASSERT_FALSE(aws_host_utils_is_ipv6(aws_byte_cursor_from_c_str("::2001:0db8:0000:0000:8a2e:0370:7334"), false));
 
     ASSERT_FALSE(aws_host_utils_is_ipv6(aws_byte_cursor_from_c_str("fe80::1%en0"), true));
     ASSERT_FALSE(aws_host_utils_is_ipv6(aws_byte_cursor_from_c_str("fe80::1%24en0"), true));