helper functions, re-imports

dnstp-client/src/main.rs

@@ -6,11 +6,8 @@ use clap::Parser;
 use log::{info, LevelFilter};
 use rand::RngCore;
 use simplelog::*;
-use dnstplib::message::header::{Direction, DNSHeader, Opcode, ResponseCode};
-use dnstplib::message::question::{DNSQuestion, QClass, QType};
-use dnstplib::message::request::DNSRequest;
-use dnstplib::net::socket::DNSSocket;
-use dnstplib::net::raw_request::NetworkMessage;
+use dnstplib::message::{DNSQuestion, DNSRequest, DNSHeader, QClass, QType, Direction, Opcode, ResponseCode};
+use dnstplib::net::{DNSSocket, NetworkMessage};
 use dnstplib::processor::ResponseProcesor;
 
 #[derive(Parser, Debug)]
@@ -49,31 +46,7 @@ fn main() {
 
         info!("sending...");
 
-        let message = DNSRequest {
-            header: DNSHeader {
-                id: rng.next_u32() as u16,
-                direction: Direction::Request,
-                opcode: Opcode::Query,
-                authoritative: false,
-                truncation: false,
-                recursion_desired: true,
-                recursion_available: false,
-                valid_zeroes: true,
-                response: ResponseCode::NoError,
-                question_count: 1,
-                answer_record_count: 0,
-                authority_record_count: 0,
-                additional_record_count: 0
-            },
-            questions: vec![
-                DNSQuestion {
-                    qname: "duck.com".to_string(),
-                    qtype: QType::A,
-                    qclass: QClass::Internet
-                }
-            ],
-            peer: address
-        };
+        let message = DNSRequest::from_hostname(address, rng.next_u32() as u16, "duck.com".to_string());
 
         let bytes = message.to_bytes();
 

dnstp-server/src/main.rs

@@ -8,7 +8,7 @@ use simplelog::*;
 use std::fs::File;
 use std::net::SocketAddr;
 
-use dnstplib::net::socket::DNSSocket;
+use dnstplib::net::DNSSocket;
 use dnstplib::processor::RequestProcesor;
 
 /// Command-line arguments for configuring the server

dnstp/src/message/answer/a_rdata.rs

@@ -1,12 +1,12 @@
 use std::fmt::{Debug, Formatter};
-use std::net::{IpAddr, Ipv4Addr};
+use std::net::Ipv4Addr;
 use crate::message::answer::RData;
 
-pub struct IpRData {
+pub struct ARdata {
     pub rdata: Ipv4Addr
 }
 
-impl Debug for IpRData {
+impl Debug for ARdata {
     fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
         f.debug_struct("IP")
             .field("data", &self.rdata)
@@ -14,16 +14,16 @@ impl Debug for IpRData {
     }
 }
 
-impl RData for IpRData {
+impl RData for ARdata {
     fn to_bytes(&self) -> Vec<u8> {
         return self.rdata.octets().to_vec();
     }
 }
 
-impl IpRData {
-    pub fn from(rdata: Ipv4Addr) -> IpRData
+impl ARdata {
+    pub fn from(rdata: Ipv4Addr) -> ARdata
     {
-        IpRData {
+        ARdata {
             rdata
         }
     }

dnstp/src/message/answer/mod.rs

@@ -1,17 +1,16 @@
 mod raw_rdata;
 pub use raw_rdata::RawRData;
 
-mod ip_address;
-pub use ip_address::IpRData;
+mod a_rdata;
+pub use a_rdata::ARdata;
 
 #[cfg(test)]
 mod tests;
 
-use std::fmt::{Debug, Display};
+use std::fmt::Debug;
+use std::fmt::Display;
 use crate::byte::{four_byte_split, two_byte_split};
-use crate::message::question::{DNSQuestion, QClass, QType, QuestionParseError};
-use crate::string::encode_domain_name;
-
+use crate::message::question::{DNSQuestion, QClass, QType};
 
 pub trait RData: Debug {
     fn to_bytes(&self) -> Vec<u8>;
@@ -19,7 +18,7 @@ pub trait RData: Debug {
 
 #[derive(Debug)]
 pub struct DNSAnswer {
-    pub name: String,
+    pub name_offset: u16,
     pub answer_type: QType,
     pub class: QClass,
     pub ttl: u32,
@@ -31,7 +30,8 @@ impl DNSAnswer {
 
     pub fn to_bytes(&self) -> Vec<u8>
     {
-        let mut ret = encode_domain_name(&self.name);
+        let (name_1, name_2) = two_byte_split(self.name_offset | (0b11 << 14));
+        let mut ret = vec![name_1, name_2];
 
         let type_split = two_byte_split(self.answer_type as u16);
         ret.push(type_split.0);
@@ -56,10 +56,10 @@ impl DNSAnswer {
         return ret
     }
 
-    pub fn from_query(query: &DNSQuestion, data: Box<dyn RData>, ttl: Option<u32>) -> DNSAnswer
+    pub fn from_query(query: &DNSQuestion, name_offset: u16, data: Box<dyn RData>, ttl: Option<u32>) -> DNSAnswer
     {
         DNSAnswer {
-            name: query.qname.clone(),
+            name_offset,
             answer_type: query.qtype,
             class: query.qclass,
             ttl: ttl.unwrap_or(0),

dnstp/src/message/answer/tests.rs

@@ -6,7 +6,8 @@ use super::*;
 #[ignore]
 fn one_answer_back_and_forth() {
     let q = DNSAnswer {
-        name: "google.com".to_string(),
+        // name_offset: "google.com".to_string(),
+        name_offset: 12,
         answer_type: QType::A,
         class: QClass::Internet,
         ttl: 0,
@@ -19,7 +20,7 @@ fn one_answer_back_and_forth() {
 
     let (q_read, q_reconstructed) = answers_from_bytes(q_bytes, 0).unwrap();
 
-    assert_eq!(q.name, q_reconstructed[0].name);
+    assert_eq!(q.name_offset, q_reconstructed[0].name_offset);
     assert_eq!(q.answer_type, q_reconstructed[0].answer_type);
     assert_eq!(q.class, q_reconstructed[0].class);
     assert_eq!(q.ttl, q_reconstructed[0].ttl);

dnstp/src/message/header.rs

@@ -1,6 +1,7 @@
 use std::convert::TryFrom;
 use crate::byte::apply_split_bytes;
-use crate::message::header::Direction::Response;
+
+use crate::message::Direction::Response;
 
 /// Size in bytes for a DNS message
 pub const HEADER_SIZE: usize = 12;
@@ -127,4 +128,26 @@ impl DNSHeader {
 
         header_bytes
     }
+
+    pub fn new_request(id: u16, questions: Option<u16>) -> DNSHeader
+    {
+        DNSHeader {
+            id,
+            direction: Direction::Request,
+            opcode: Opcode::Query,
+            authoritative: false,
+            truncation: false,
+            recursion_desired: true,
+            recursion_available: false,
+            valid_zeroes: true,
+            response: ResponseCode::NoError,
+            question_count: match questions {
+                None => 1,
+                Some(v) => v
+            },
+            answer_record_count: 0,
+            authority_record_count: 0,
+            additional_record_count: 0
+        }
+    }
 }

dnstp/src/message/mod.rs

@@ -4,3 +4,9 @@ pub mod question;
 pub mod request;
 pub mod answer;
 pub mod response;
+
+pub use question::{DNSQuestion, QClass, QType, QuestionParseError, questions_to_bytes, questions_from_bytes};
+pub use answer::{DNSAnswer, RawRData, RData, ARdata, AnswerParseError, answers_to_bytes, answers_from_bytes};
+pub use header::{DNSHeader, Direction, Opcode, ResponseCode, HEADER_SIZE};
+pub use request::DNSRequest;
+pub use response::DNSResponse;

dnstp/src/message/question/mod.rs

@@ -2,8 +2,10 @@
 mod tests;
 
 use urlencoding::decode;
+use crate::byte::{two_byte_extraction, two_byte_split};
 use crate::string::encode_domain_name;
 
+#[repr(u16)]
 #[derive(Ord, PartialOrd, Eq, PartialEq, Debug, Copy, Clone)]
 pub enum QType {
     A = 1,
@@ -21,29 +23,30 @@ pub enum QType {
     SRV = 33
 }
 
-impl TryFrom<u8> for QType {
-    type Error = u8;
+impl TryFrom<u16> for QType {
+    type Error = u16;
 
-    fn try_from(v: u8) -> Result<Self, Self::Error> {
+    fn try_from(v: u16) -> Result<Self, Self::Error> {
         match v {
-            x if x == QType::A as u8 => Ok(QType::A),
-            x if x == QType::NS as u8 => Ok(QType::NS),
-            x if x == QType::CNAME as u8 => Ok(QType::CNAME),
-            x if x == QType::SOA as u8 => Ok(QType::SOA),
-            x if x == QType::WKS as u8 => Ok(QType::WKS),
-            x if x == QType::PTR as u8 => Ok(QType::PTR),
-            x if x == QType::HINFO as u8 => Ok(QType::HINFO),
-            x if x == QType::MINFO as u8 => Ok(QType::MINFO),
-            x if x == QType::MX as u8 => Ok(QType::MX),
-            x if x == QType::TXT as u8 => Ok(QType::TXT),
-            x if x == QType::RP as u8 => Ok(QType::RP),
-            x if x == QType::AAAA as u8 => Ok(QType::AAAA),
-            x if x == QType::SRV as u8 => Ok(QType::SRV),
+            x if x == QType::A as u16 => Ok(QType::A),
+            x if x == QType::NS as u16 => Ok(QType::NS),
+            x if x == QType::CNAME as u16 => Ok(QType::CNAME),
+            x if x == QType::SOA as u16 => Ok(QType::SOA),
+            x if x == QType::WKS as u16 => Ok(QType::WKS),
+            x if x == QType::PTR as u16 => Ok(QType::PTR),
+            x if x == QType::HINFO as u16 => Ok(QType::HINFO),
+            x if x == QType::MINFO as u16 => Ok(QType::MINFO),
+            x if x == QType::MX as u16 => Ok(QType::MX),
+            x if x == QType::TXT as u16 => Ok(QType::TXT),
+            x if x == QType::RP as u16 => Ok(QType::RP),
+            x if x == QType::AAAA as u16 => Ok(QType::AAAA),
+            x if x == QType::SRV as u16 => Ok(QType::SRV),
             _ => Err(v),
         }
     }
 }
 
+#[repr(u16)]
 #[derive(Ord, PartialOrd, Eq, PartialEq, Debug, Copy, Clone)]
 pub enum QClass {
     Internet = 1,
@@ -51,14 +54,14 @@ pub enum QClass {
     Hesiod = 4,
 }
 
-impl TryFrom<u8> for QClass {
-    type Error = u8;
+impl TryFrom<u16> for QClass {
+    type Error = u16;
 
-    fn try_from(v: u8) -> Result<Self, Self::Error> {
+    fn try_from(v: u16) -> Result<Self, Self::Error> {
         match v {
-            x if x == QClass::Internet as u8 => Ok(QClass::Internet),
-            x if x == QClass::Chaos as u8 => Ok(QClass::Chaos),
-            x if x == QClass::Hesiod as u8 => Ok(QClass::Hesiod),
+            x if x == QClass::Internet as u16 => Ok(QClass::Internet),
+            x if x == QClass::Chaos as u16 => Ok(QClass::Chaos),
+            x if x == QClass::Hesiod as u16 => Ok(QClass::Hesiod),
             _ => Err(v),
         }
     }
@@ -85,8 +88,15 @@ impl DNSQuestion {
     {
         let mut ret = encode_domain_name(&self.qname);
 
-        ret.push(self.qtype as u8);
-        ret.push(self.qclass as u8);
+        let (qtype_1, qtype_2) = two_byte_split(self.qtype as u16);
+
+        ret.push(qtype_1);
+        ret.push(qtype_2);
+
+        let (qclass_1, qclass_2) = two_byte_split(self.qclass as u16);
+
+        ret.push(qclass_1);
+        ret.push(qclass_2);
 
         ret
     }
@@ -107,8 +117,8 @@ pub fn questions_to_bytes(questions: &Vec<DNSQuestion>) -> Vec<u8>
 #[derive(Ord, PartialOrd, Eq, PartialEq, Debug)]
 pub enum QuestionParseError {
     ShortLength(usize),
-    QTypeParse(u8),
-    QClassParse(u8)
+    QTypeParse(u16),
+    QClassParse(u16)
 }
 
 pub fn questions_from_bytes(bytes: Vec<u8>, total_questions: u16) -> Result<(i32, Vec<DNSQuestion>), QuestionParseError>
@@ -123,7 +133,8 @@ pub fn questions_from_bytes(bytes: Vec<u8>, total_questions: u16) -> Result<(i32
 
     let mut current_length: Option<u8> = None;
     let mut remaining_length: u8 = 0;
-    let mut current_qtype: Option<u8> = None;
+    let mut current_qtype: (Option<u8>, Option<u8>) = (None, None);
+    let mut current_qclass: (Option<u8>, Option<u8>) = (None, None);
     let mut trailers_reached = false;
 
     let mut byte_counter  = 0;
@@ -137,7 +148,7 @@ pub fn questions_from_bytes(bytes: Vec<u8>, total_questions: u16) -> Result<(i32
                 current_query.clear();
             }
             Some(_) => {
-                if byte == 0 {
+                if byte == 0 && !trailers_reached {
                     trailers_reached = true;
                     continue
                 }
@@ -148,12 +159,19 @@ pub fn questions_from_bytes(bytes: Vec<u8>, total_questions: u16) -> Result<(i32
                     remaining_length = byte;
                 }
                 else if trailers_reached { // trailer fields
-                    match current_qtype {
-                        None => {
-                            current_qtype = Some(byte);
+                    match (current_qtype, current_qclass) {
+                        ((None, _), (_, _)) => {
+                            current_qtype.0 = Some(byte);
+                        },
+                        ((_, None), (_, _)) => {
+                            current_qtype.1 = Some(byte);
+                        },
+                        ((_, _), (None, _)) => {
+                            current_qclass.0 = Some(byte);
                         }
-                        Some(qtype_b) => {
-                            match (qtype_b.try_into(), byte.try_into()) {
+                        ((Some(qtype_1), Some(qtype_2)), (Some(qclass_1), None)) => {
+                            match (two_byte_extraction(&[qtype_1, qtype_2], 0).try_into(),
+                                   two_byte_extraction(&[qclass_1, byte], 0).try_into()) {
                                 (Ok(qtype), Ok(qclass)) => {
                                     questions.push(DNSQuestion {
                                         qname: decode(String::from_utf8(current_query.clone()).unwrap().as_str()).unwrap().to_string(),
@@ -168,7 +186,8 @@ pub fn questions_from_bytes(bytes: Vec<u8>, total_questions: u16) -> Result<(i32
                                     current_length = None;
                                     remaining_length = byte;
                                     current_query.clear();
-                                    current_qtype = None;
+                                    current_qtype = (None, None);
+                                    current_qclass = (None, None);
                                     trailers_reached = false;
                                 }
                                 (Err(qtype_e), _) => {
@@ -179,6 +198,7 @@ pub fn questions_from_bytes(bytes: Vec<u8>, total_questions: u16) -> Result<(i32
                                 }
                             }
                         }
+                        _ => {}
                     }
                 }
                 else {

dnstp/src/message/request.rs

@@ -1,11 +1,11 @@
 use std::net::SocketAddr;
-use crate::message::header::DNSHeader;
-use crate::message::question::{DNSQuestion, questions_to_bytes};
+use crate::message::{DNSQuestion, DNSHeader, questions_to_bytes, Direction, Opcode, ResponseCode, QType, QClass};
 
 #[derive(Ord, PartialOrd, Eq, PartialEq, Debug, Clone)]
 pub struct DNSRequest {
     pub header: DNSHeader,
     pub questions: Vec<DNSQuestion>,
+    pub additional_records: Vec<DNSQuestion>,
     pub peer: SocketAddr
 }
 
@@ -20,4 +20,38 @@ impl DNSRequest {
 
         return header_bytes
     }
+
+    pub fn from_hostname(peer: SocketAddr, id: u16, hostname: String) -> DNSRequest
+    {
+        DNSRequest {
+            header: DNSHeader::new_request(id, None),
+            questions: vec![
+                DNSQuestion {
+                    qname: hostname,
+                    qtype: QType::A,
+                    qclass: QClass::Internet
+                }
+            ],
+            additional_records: vec![],
+            peer
+        }
+    }
+
+    pub fn from_hostnames(peer: SocketAddr, id: u16, hostnames: Vec<String>) -> DNSRequest
+    {
+        DNSRequest {
+            header: DNSHeader::new_request(id, Some(hostnames.len() as u16)),
+            questions: hostnames
+                .into_iter()
+                .map(|n|
+                    DNSQuestion {
+                        qname: n,
+                        qclass: QClass::Internet,
+                        qtype: QType::A
+                    })
+                .collect(),
+            additional_records: vec![],
+            peer
+        }
+    }
 }

dnstp/src/message/response.rs

@@ -1,7 +1,5 @@
-use std::net::SocketAddr;
-use crate::message::answer::{answers_to_bytes, DNSAnswer};
-use crate::message::header::DNSHeader;
-use crate::message::question::{DNSQuestion, questions_to_bytes};
+use std::net::{Ipv4Addr, SocketAddr};
+use crate::message::{Direction, DNSHeader, DNSRequest, ResponseCode, answers_to_bytes, ARdata, DNSAnswer, DNSQuestion, questions_to_bytes};
 
 #[derive(Debug)]
 pub struct DNSResponse {
@@ -24,4 +22,35 @@ impl DNSResponse {
 
         return header_bytes
     }
+
+    pub fn a_from_request(request: &DNSRequest, ip: impl Fn(&DNSQuestion) -> Ipv4Addr) -> DNSResponse
+    {
+        let mut response = DNSResponse{
+            header: request.header.clone(),
+            questions: request.questions.clone(),
+            answers: vec![],
+            peer: request.peer
+        };
+
+        response.answers = request.questions
+            .iter()
+            .map(|x|
+                DNSAnswer::from_query(x,
+                                      12,
+                                      Box::from(ARdata::from(ip(x))),
+                                      None))
+            .collect();
+
+        response.header.direction = Direction::Response;
+        response.header.response = ResponseCode::NoError;
+        response.header.answer_record_count = response.answers.len() as u16;
+        response.header.authority_record_count = 0;
+        response.header.additional_record_count = 0;
+
+        if response.header.recursion_desired {
+            response.header.recursion_available = true;
+        }
+
+        response
+    }
 }

dnstp/src/net/mod.rs

@@ -1,6 +1,5 @@
 pub mod socket;
-// pub mod processor;
-//
-// pub mod processor::request_processor;
-// pub mod processor::response_processor;
 pub mod raw_request;
+
+pub use raw_request::{NetworkMessage, NetworkMessagePtr};
+pub use socket::DNSSocket;

dnstp/src/net/socket.rs

@@ -4,8 +4,9 @@ use std::thread::{JoinHandle};
 use log::{debug, error, info};
 use std::sync::mpsc;
 use std::sync::mpsc::{Receiver, Sender, TryRecvError};
-use crate::message::header::HEADER_SIZE;
-use crate::net::raw_request::{NetworkMessage, NetworkMessagePtr};
+
+use crate::message::HEADER_SIZE;
+use crate::net::{NetworkMessage, NetworkMessagePtr};
 
 pub struct DNSSocket {
     addresses: Vec<SocketAddr>,

dnstp/src/processor/request.rs

@@ -1,13 +1,11 @@
-use std::net::{IpAddr, Ipv4Addr};
+use std::net::Ipv4Addr;
 use std::sync::mpsc;
 use std::sync::mpsc::{Receiver, Sender};
 use std::thread;
 use log::{error, info};
-use crate::message::answer::{DNSAnswer, IpRData, RawRData};
-use crate::message::header::{Direction, ResponseCode};
-use crate::message::question::QuestionParseError;
-use crate::message::response::DNSResponse;
-use crate::net::raw_request::{NetworkMessage, NetworkMessagePtr};
+
+use crate::message::{QuestionParseError, DNSResponse};
+use crate::net::{NetworkMessage, NetworkMessagePtr};
 use crate::request_parser::{HeaderParseError, parse_request, RequestParseError};
 
 pub struct RequestProcesor {
@@ -36,24 +34,7 @@ impl RequestProcesor {
                     Ok(r) => {
                         info!("received dns message: {:?}", r);
 
-                        let mut response = DNSResponse{
-                            header: r.header.clone(),
-                            questions: r.questions.clone(),
-                            answers: vec![],
-                            peer: r.peer
-                        };
-
-                        // response.answers = r.questions.iter().map(|x| DNSAnswer::from_query(x, Box::from(IpRData::from(Ipv4Addr::from([127, 0, 0, 1]))), None)).collect();
-
-                        response.header.direction = Direction::Response;
-                        response.header.response = ResponseCode::NameError;
-                        response.header.answer_record_count = 0;
-                        response.header.authority_record_count = 0;
-                        response.header.additional_record_count = 0;
-
-                        if response.header.recursion_desired {
-                            response.header.recursion_available = true;
-                        }
+                        let mut response = DNSResponse::a_from_request(&r, |q| Ipv4Addr::from([127, 0, 0, 1]));
 
                         sending_channel.send(Box::from(
                             NetworkMessage {

dnstp/src/processor/response.rs

@@ -3,6 +3,7 @@ use std::sync::mpsc::{Receiver, Sender};
 use std::thread;
 use log::info;
 use std::str;
+use crate::message::DNSResponse;
 use crate::net::raw_request::NetworkMessagePtr;
 
 pub struct ResponseProcesor {
@@ -25,9 +26,7 @@ impl ResponseProcesor {
 
             for mut m in rx
             {
-                info!("processing: {}", str::from_utf8(&(*(*m).buffer)).unwrap());
-
-                // (*(*m).buffer).reverse();
+                info!("processing response");
 
                 // match sending_channel.send(m) {
                 //     Ok(_) => {}

dnstp/src/request_parser.rs

@@ -1,8 +1,6 @@
 use crate::byte;
-use crate::message::header::{Direction, DNSHeader, Opcode, ResponseCode};
-use crate::message::question::{QuestionParseError, questions_from_bytes};
-use crate::message::request::DNSRequest;
-use crate::net::raw_request::NetworkMessage;
+use crate::message::{DNSRequest, Direction, DNSHeader, Opcode, ResponseCode, QuestionParseError, questions_from_bytes};
+use crate::net::NetworkMessage;
 use crate::request_parser::RequestParseError::{HeaderParse, QuesionsParse};
 
 pub const ID_START: usize = 0;
@@ -90,14 +88,27 @@ pub fn parse_request(msg: NetworkMessage) -> Result<DNSRequest, RequestParseErro
         Ok(header) => {
             let mut trimmed = msg.buffer.to_vec();
             trimmed.drain(0 .. 12);
+            let buffer_size = trimmed.len();
             match questions_from_bytes(trimmed, header.question_count)
             {
                 Ok((bytes_read, questions)) => {
-                    Ok(DNSRequest {
-                        header,
-                        questions,
-                        peer: msg.peer
-                    })
+
+                    if buffer_size > bytes_read as usize {
+                        Ok(DNSRequest {
+                            header,
+                            questions,
+                            peer: msg.peer,
+                            additional_records: vec![]
+                        })
+                    }
+                    else {
+                        Ok(DNSRequest {
+                            header,
+                            questions,
+                            peer: msg.peer,
+                            additional_records: vec![]
+                        })
+                    }
                 }
                 Err(e) => Err(QuesionsParse(e))
             }