add serializing functions for single edns options and option lists

diff --git a/edns.c b/edns.c
index 1d786b6c85b1ca51130fa815096155d5a1af8807..f6a8a797be594f135a77d66b98895ea350c53757 100644 (file)
--- a/edns.c
+++ b/edns.c
@@ -39,6 +39,37 @@ ldns_edns_get_data(const ldns_edns_option *edns)
        return edns->_data;
 }
 
+ldns_buffer *
+ldns_edns_get_wireformat_buffer(const ldns_edns_option *edns)
+{
+       uint16_t option;
+       size_t size;
+       uint8_t* data;
+       ldns_buffer* buffer;
+
+       if (edns == NULL) {
+               return NULL;
+       }
+
+       option = ldns_edns_get_code(edns);
+       size = ldns_edns_get_size(edns);
+       data = ldns_edns_get_data(edns);
+
+       buffer = ldns_buffer_new(size + 4);
+
+       if (buffer == NULL) {
+               return NULL;
+       }
+
+       ldns_buffer_write_u16(buffer, option);
+       ldns_buffer_write_u16(buffer, size);
+       ldns_buffer_write(buffer, data, size);
+
+       ldns_buffer_flip(buffer);
+
+       return buffer;
+}
+
 /* write */
 void
 ldns_edns_set_size(ldns_edns_option *edns, size_t size)
@@ -71,9 +102,32 @@ ldns_edns_new(ldns_edns_option_code code, size_t size, void *data)
        if (!edns) {
                return NULL;
        }
-       ldns_edns_set_size(edns, size);
        ldns_edns_set_code(edns, code);
+       ldns_edns_set_size(edns, size);
        ldns_edns_set_data(edns, data);
+
+       return edns;
+}
+
+ldns_edns_option *
+ldns_edns_new_from_data(ldns_edns_option_code code, size_t size, const void *data)
+{
+       ldns_edns_option *edns;
+       edns = LDNS_MALLOC(ldns_edns_option);
+       if (!edns) {
+               return NULL;
+       }
+       edns->_data = LDNS_XMALLOC(uint8_t, size);
+       if (!edns->_data) {
+               LDNS_FREE(edns);
+               return NULL;
+       }
+
+       /* set the values */
+       ldns_edns_set_code(edns, code);
+       ldns_edns_set_size(edns, size);
+       memcpy(edns->_data, data, size);
+
        return edns;
 }
 
@@ -146,7 +200,7 @@ ldns_edns_option_list_get_count(const ldns_edns_option_list *option_list)
 void
 ldns_edns_option_list_set_count(ldns_edns_option_list *option_list, size_t count)
 {
-       assert(option_list); // @TODO does this check need to check more?
+       assert(option_list);
        option_list->_option_count = count;
 }
 
@@ -196,7 +250,7 @@ ldns_edns_option_list_set_option(ldns_edns_option_list *option_list,
 
        option_list->_options_size += (ldns_edns_get_size(option) + 4);
 
-       /* overwrite the pointer of "old" */
+       /* overwrite the pointer of the old entry */
        option_list->_options[index] = (ldns_edns_option*)option;
        return old;
 }
@@ -209,8 +263,7 @@ ldns_edns_option_list_push(ldns_edns_option_list *option_list,
 
        if (option != NULL) {
 
-               // @TODO rethink reallocing per push
-
+               /* grow the array */
                option_list->_options = LDNS_XREALLOC(option_list->_options,
                        ldns_edns_option *, option_list->_option_count + 1);
                if (!option_list) {
@@ -242,8 +295,6 @@ ldns_edns_option_list_pop(ldns_edns_option_list *option_list)
        /* get the last option from the list */
        pop = ldns_edns_option_list_get_option(option_list, count-1);
 
-       // @TODO rethink reallocing per pop
-
        /* shrink the array */
        new_list = LDNS_XREALLOC(option_list->_options, ldns_edns_option *, count -1);
        if (new_list){
@@ -260,3 +311,46 @@ ldns_edns_option_list_pop(ldns_edns_option_list *option_list)
        return pop;
 }
 
+ldns_buffer *
+ldns_edns_option_list2wireformat_buffer(const ldns_edns_option_list *option_list)
+{
+       size_t i, list_size, options_size, option, size;
+       ldns_buffer* buffer;
+       ldns_edns_option *edns;
+       uint8_t* data = NULL;
+
+       /* get the number of EDNS options in the list*/
+       list_size = ldns_edns_option_list_get_count(option_list);
+
+       /* create buffer the size of the total EDNS wireformat options */
+       options_size = ldns_edns_option_list_get_options_size(option_list);
+       buffer = ldns_buffer_new(options_size);
+
+       /* write individual serialized EDNS options to final buffer*/
+       for (i = 0; i < list_size; i++) {
+               edns = ldns_edns_option_list_get_option(option_list, i);
+
+               if (edns == NULL) {
+                       /* this shouldn't be possible */
+                       return NULL;
+               }
+
+               option = ldns_edns_get_code(edns);
+               size = ldns_edns_get_size(edns);
+               data = ldns_edns_get_data(edns);
+
+               /* make sure the option fits */
+               if (ldns_buffer_capacity(buffer) > size + 4) {
+                       ldns_buffer_free(buffer);
+                       return NULL;
+               }
+
+               ldns_buffer_write_u16(buffer, option);
+               ldns_buffer_write_u16(buffer, size);
+               ldns_buffer_write(buffer, data, size);
+       }
+
+       ldns_buffer_flip(buffer);
+
+       return buffer;
+}

diff --git a/ldns/edns.h b/ldns/edns.h
index c6c2ebb11838fda306728a5a7f1db13220d50200..9d821ee9f7ebf185f30780ecaf36c6a26899e3bf 100644 (file)
--- a/ldns/edns.h
+++ b/ldns/edns.h
@@ -95,9 +95,9 @@ typedef enum ldns_edns_enum_ede_code ldns_edns_ede_code;
      +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
  */
 struct ldns_struct_edns_option {
-               ldns_edns_option_code _code;
-               size_t                _size;
-               void                 *_data;
+       ldns_edns_option_code _code;
+       size_t                _size;
+       void                 *_data;
 };
 typedef struct ldns_struct_edns_option ldns_edns_option;
 
@@ -108,7 +108,7 @@ typedef struct ldns_struct_edns_option ldns_edns_option;
 struct ldns_struct_edns_option_list
 {
        size_t _option_count;
-       size_t _options_size; /* the total size of the options in the list*/
+       size_t _options_size; /* the total size of the options serialized */
        ldns_edns_option **_options;
 };
 typedef struct ldns_struct_edns_option_list ldns_edns_option_list;
@@ -134,11 +134,19 @@ ldns_edns_option_code ldns_edns_get_code(const ldns_edns_option *edns);
 
 /**
  * returns the EDNS option data.
- * \param[in] *edns the rdf to read from
- * \return uint8_t* pointer to the rdf's data
+ * \param[in] *edns the EDNS option to read from
+ * \return uint8_t* pointer to the EDNS option's data
  */
 uint8_t *ldns_edns_get_data(const ldns_edns_option *edns);
 
+
+/**
+ * serialise the EDNS option into wireformat.
+ * \param[in] *edns the EDNS option to read from
+ * \return ldns_buffer* the buffer containing the data
+ */
+ldns_buffer *ldns_edns_get_wireformat_buffer(const ldns_edns_option *edns);
+
 /* Constructors and destructors*/
 
 /**
@@ -151,6 +159,9 @@ uint8_t *ldns_edns_get_data(const ldns_edns_option *edns);
  */
 ldns_edns_option *ldns_edns_new(ldns_edns_option_code code, size_t size, void *data);
 
+// @TODO write this/determine if we need it
+ldns_edns_option *ldns_edns_new_from_data(ldns_edns_option_code code, size_t size, const void *data);
+
 void ldns_edns_deep_free(ldns_edns_option *edns);
 void ldns_edns_free(ldns_edns_option *edns);
 
@@ -222,6 +233,13 @@ bool ldns_edns_option_list_push(ldns_edns_option_list *options_list,
  */
 ldns_edns_option* ldns_edns_option_list_pop(ldns_edns_option_list *options_list);
 
+/**
+ * serializes all the EDNS options into a single wireformat buffer
+ * \param[in] options_list  the EDNS options_list to combine into one wireformat
+ * \return the filled buffer or NULL on failure
+ */
+ldns_buffer *ldns_edns_option_list2wireformat_buffer(const ldns_edns_option_list *option_list);
+
 #ifdef __cplusplus
 }
 #endif