DNS first draft mostly done, just need to write validator and action for full msg

examples/dns.c

@@ -1,36 +1,85 @@
 #include "../hammer.h"
 
 bool is_zero(parse_result_t *p) {
+  return (0 == p->ast->uint);
+}
+
+bool validate_dns(parse_result_t *p) {
   
 }
 
 int main(int argc, char **argv) {
 
-  const parser_t dns_header = sequence(bits(16), // ID
-				       bits(1),  // QR
-				       bits(4),  // opcode
-				       bits(1),  // AA
-				       bits(1),  // TC
-				       bits(1),  // RD
-				       bits(1),  // RA
-				       ignore(attr_bool(bits(3), is_zero)), // Z
-				       bits(4),  // RCODE
+  const parser_t dns_header = sequence(bits(16, false), // ID
+				       bits(1, false),  // QR
+				       bits(4, false),  // opcode
+				       bits(1, false),  // AA
+				       bits(1, false),  // TC
+				       bits(1, false),  // RD
+				       bits(1, false),  // RA
+				       ignore(attr_bool(bits(3, false), is_zero)), // Z
+				       bits(4, false),  // RCODE
 				       uint16(), // QDCOUNT
 				       uint16(), // ANCOUNT
 				       uint16(), // NSCOUNT
 				       uint16(), // ARCOUNT
 				       NULL);
 
-  const parser_t *dns_question = sequence(;
+  const parser_t *dns_question = sequence(length_value(uint8(), uint8()), // QNAME
+					  uint16(),                       // QTYPE
+					  uint16(),                       // QCLASS
+					  NULL);
 
-  bool validate_dns(parse_result_t *p) {
+  const parser_t *letter = choice(range('a', 'z'),
+				  range('A', 'Z'),
+				  NULL);
+
+  const parser_t *let_dig = choice(letter,
+				   range('0', '9'),
+				   NULL);
+
+  const parser_t *ldh_str = many1(choice(let_dig,
+					 ch('-'),
+					 NULL));
+
+  const parser_t *label = sequence(letter,
+				   optional(sequence(optional(ldh_str),
+						     let_dig,
+						     NULL)),
+				   NULL);
+
+  /**
+   * You could write it like this ...
+   *   parser_t *indirect_subdomain = indirect();
+   *   const parser_t *subdomain = choice(label,
+   *				          sequence(indirect_subdomain,
+   *					           ch('.'),
+   *					           label,
+   *					           NULL),
+   *				          NULL);
+   *   bind_indirect(indirect_subdomain, subdomain);
+   *
+   * ... but this is easier and equivalent
+   */
+
+  parser_t *subdomain = sepBy1(label, ch('.'));
+
+  const parser_t *domain = choice(subdomain, 
+				  ch(' '), 
+				  NULL);
+
+  const parser_t *dns_rr = sequence(domain,                         // NAME
+				    uint16(),                       // TYPE
+				    uint16(),                       // CLASS
+				    uint32(),                       // TTL
+				    length_value(uint16(), uint8()) // RDLENGTH+RDATA
+				    NULL);
 
-  }
 
   const parser_t *dns_message = attr_bool(sequence(dns_header,
-						   many(dns_question),
-						   many(dns_answer),
-						   many(dns_authority),
-						   many(dns_additional),
+						   dns_question,
+						   many(dns_rr),
+						   end_p(),
 						   NULL),
 					  validate_dns);
+}