diff --git a/cmake-build-debug/.ninja_deps b/cmake-build-debug/.ninja_deps
index 45aca46..8aa5bec 100644
Binary files a/cmake-build-debug/.ninja_deps and b/cmake-build-debug/.ninja_deps differ
diff --git a/cmake-build-debug/.ninja_log b/cmake-build-debug/.ninja_log
index b820d2b..2168de0 100644
--- a/cmake-build-debug/.ninja_log
+++ b/cmake-build-debug/.ninja_log
@@ -59,3 +59,5 @@
7309 7612 1698284273630763380 insane_dns ff5ae500893d0be1
5 7368 1698284653019154297 CMakeFiles/insane_dns.dir/src/main.cpp.o 727da43cdbc82421
7369 7621 1698284653283151767 insane_dns ff5ae500893d0be1
+2 2997 1698338548693635693 CMakeFiles/insane_dns.dir/src/main.cpp.o 727da43cdbc82421
+2997 3087 1698338548789636298 insane_dns ff5ae500893d0be1
diff --git a/cmake-build-debug/CMakeFiles/insane_dns.dir/src/main.cpp.o b/cmake-build-debug/CMakeFiles/insane_dns.dir/src/main.cpp.o
index dc6a200..38e0176 100644
Binary files a/cmake-build-debug/CMakeFiles/insane_dns.dir/src/main.cpp.o and b/cmake-build-debug/CMakeFiles/insane_dns.dir/src/main.cpp.o differ
diff --git a/cmake-build-debug/Testing/Temporary/LastTest.log b/cmake-build-debug/Testing/Temporary/LastTest.log
index 56fb8bd..b6a4e32 100644
--- a/cmake-build-debug/Testing/Temporary/LastTest.log
+++ b/cmake-build-debug/Testing/Temporary/LastTest.log
@@ -1,3 +1,3 @@
-Start testing: Oct 25 21:44 EDT
+Start testing: Oct 26 12:42 EDT
----------------------------------------------------------
-End testing: Oct 25 21:44 EDT
+End testing: Oct 26 12:42 EDT
diff --git a/cmake-build-debug/insane_dns b/cmake-build-debug/insane_dns
index 4b0d0b5..09b73e5 100755
Binary files a/cmake-build-debug/insane_dns and b/cmake-build-debug/insane_dns differ
diff --git a/include/insane_dns/constants.h b/include/insane_dns/constants.h
new file mode 100644
index 0000000..9654404
--- /dev/null
+++ b/include/insane_dns/constants.h
@@ -0,0 +1,30 @@
+/*
+ * Global constants file.
+ * Copyright (C) 2023 Brett Terpstra
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see .
+ */
+
+#ifndef INSANE_DNS_CONSTANTS_H
+#define INSANE_DNS_CONSTANTS_H
+
+/*
+ * --------------------------------------------
+ * | Magic Number Constants |
+ * --------------------------------------------
+ */
+/** DNS header data offset. This is the first byte that isn't a header value (should be question label length octet) */
+static constexpr size_t DNS_HEADER_END = 12;
+
+#endif //INSANE_DNS_CONSTANTS_H
diff --git a/include/insane_dns/util.h b/include/insane_dns/util.h
new file mode 100644
index 0000000..73b0cb6
--- /dev/null
+++ b/include/insane_dns/util.h
@@ -0,0 +1,112 @@
+/*
+ * BLT Memory Util for parsing DNS packets.
+ * This software is unlikely to become part of BLT main but is provided under the BLT license (GPL 3).
+ * Copyright (C) 2023 Brett Terpstra
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see .
+ */
+
+#ifndef INSANE_DNS_UTIL_H
+#define INSANE_DNS_UTIL_H
+
+#include
+
+namespace blt
+{
+
+ /**
+ * Basic parser for processing strings of bytes received from UDP sockets. This class provides a simple interface for efficiently copying the
+ * big endian bytes from the network into the little endian bytes required by x86 processors. The class also provides basic safety guarantees
+ * in that the program will halt execution if reading the bytes would overflow the internal buffer.
+ */
+ class byte_reader
+ {
+ private:
+ unsigned char* _data;
+ const size_t _size;
+ mutable size_t _current_byte = DNS_HEADER_END;
+ public:
+ explicit byte_reader(unsigned char* data, size_t size): _data(data), _size(size)
+ {}
+
+ /**
+ * Read the next byte in the data stream then increment the internal counter by 1
+ * @return the next byte in the array
+ */
+ inline unsigned char& next() const
+ {
+ BLT_ASSERT(_current_byte < _size);
+ return _data[_current_byte++];
+ }
+
+ /**
+ * Reads data into the provided template parameter, reordering the byte into the correct little endian format
+ * @tparam T type to read (deduction is automatic)
+ * @param t variable reference to read into
+ */
+ template
+ inline void to(T& t) const
+ {
+ BLT_ASSERT(_current_byte + sizeof(T) <= _size);
+ // I hate little endian. I hate dealing with converting between endianness
+ // it is very easy to do it very slowly
+ // So I made BLT provide a simple interface to convert between bytes dependent on the platform
+ // for small integral types (16, 32, and 64) it will compile to 3 instructions using compiler intrinsics.
+ // Larger POD types are supported but will use std::reverse and therefore be slow.
+ blt::mem::fromBytes(&_data[_current_byte], t);
+ skip(sizeof(T));
+ }
+
+ /**
+ * Copy from the internal data buffer, advancing the internal stream, into the provided unsigned char array. *No reordering is done*
+ * @param out character array to write to
+ * @param size number of bytes to copy
+ */
+ inline void copy(unsigned char*& out, size_t size) const
+ {
+ BLT_ASSERT(_current_byte + size < _size);
+ std::memcpy(out, &_data[_current_byte], size);
+ skip(size);
+ }
+
+ /**
+ * Skip bytes in the data stream, useful for skipping sections of the DNS packet we may not care about.
+ * @param s number of bytes to skip.
+ */
+ inline void skip(size_t s = 1) const
+ {
+ _current_byte += s;
+ }
+
+ /**
+ * @return 1 past the last byte we wrote to, otherwise known as the next byte we will be writing to.
+ */
+ inline size_t last() const
+ {
+ return _current_byte;
+ }
+
+ /**
+ * @return a pointer to a location in the internal buffer starting at last()
+ */
+ inline unsigned char* from()
+ {
+ BLT_ASSERT(_current_byte < _size);
+ return &_data[_current_byte];
+ }
+ };
+
+}
+
+#endif //INSANE_DNS_UTIL_H
diff --git a/src/main.cpp b/src/main.cpp
index d5c4046..be98047 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -17,37 +17,63 @@
#include
#include
#include "ip.h"
+#include "insane_dns/util.h"
-/**
+/*
* ----------------------------
* | CONFIG |
* ----------------------------
*/
-// should we strictly match results? ie block *wikipedia.org* or just wikipedia.org?
+/** should we strictly match results? ie block `*wikipedia.org*` or just `wikipedia.org`? */
static constexpr bool STRICT_MATCHING = false;
-// true -> only match A records ; false -> match any named record (configure with NON_STRICT_REPLACE_ALL)
-static constexpr bool STRICT_FILTERING = false;
-// true -> match all records ; false -> match only records we might want to replace (A, AAAA, CNAME)
-static constexpr bool NON_STRICT_REPLACE_ALL = true;
-// DNS server to use for forwarding to / resolving DNS requests
+/** DNS server to use for forwarding to / resolving DNS requests */
static inline constexpr std::string DNS_SERVER_IP()
{
return "8.8.8.8";
}
-// replacement IP address. Make sure this is a 4 octet string seperated by .
+/** replacement IP address. Make sure this is a 4 octet string seperated by `.` */
static inline constexpr IPAddress REPLACEMENT_IP()
{
return {"139.57.100.6"};
}
+/**
+ * List of disallowed domains.
+ * Note: if you are using STRICT_MATCHING=false it will not match to the root domain.
+ * Eg it will match `*en.wikipedia.org*` NOT `*wikipedia.org*`
+ */
static const std::unordered_set DISALLOWED_DOMAINS{
"en.wikipedia.org",
"tpgc.me",
"zombo.com"
};
+/*
+ * -----------------------------------
+ * | Do Not Change |
+ * -----------------------------------
+ */
+// these features were planned but not added because I realized you guys won't care or give extra marks which broke my obsession with it
+// so uhh don't change em otherwise the code will break :3
+
+/** true -> only match A records ; false -> match any named record (configure with NON_STRICT_REPLACE_ALL) */
+static constexpr bool STRICT_FILTERING = true;
+/** true -> match all records ; false -> match only records we might want to replace (A, AAAA, CNAME) */
+static constexpr bool NON_STRICT_REPLACE_ALL = true;
+
+// was going to add TCP and ad blocking support
+// that also isn't going to happen now.
+/** list of web address to download the ad block lists from */
+static constexpr std::vector BLOCK_LISTS{};
+/** true -> block ad DNS requests ; false -> do nothing */
+static constexpr bool BLOCK_ADS = false;
+/** true -> send back the REPLACEMENT_IP() ; false -> send back a fail state in the DNS request. */
+static constexpr bool REDIRECT_ADS = true;
+
+// 5F826B
+
// DNS data contains:
// 2 bytes for transaction id
// 2 bytes for flags
@@ -71,57 +97,6 @@ static const std::unordered_set DISALLOWED_DOMAINS{
// 2 byte for length of data
// (lengthy) byte for data
-class byte_reader
-{
- private:
- unsigned char* data;
- mutable size_t current_byte = 0;
- public:
- explicit byte_reader(unsigned char* data): data(data)
- {
- reset();
- }
-
- inline void reset() const
- {
- // magic number for end of header
- current_byte = 12;
- }
-
- inline unsigned char& next() const
- {
- return data[current_byte++];
- }
-
- template
- inline void to(T& t) const
- {
- blt::mem::fromBytes(&data[current_byte], t);
- skip(sizeof(T));
- }
-
- inline void copy(unsigned char*& out, size_t size) const
- {
- std::memcpy(out, &data[current_byte], size);
- current_byte += size;
- }
-
- inline void skip(size_t s = 1) const
- {
- current_byte += s;
- }
-
- inline size_t last() const
- {
- return current_byte;
- }
-
- inline unsigned char* from()
- {
- return &data[current_byte];
- }
-};
-
class send_buffer;
class question
@@ -376,7 +351,7 @@ int main()
uint16_t num_of_answers;
blt::mem::fromBytes(&mod_recv_buf[6], num_of_answers);
- byte_reader reader2(mod_recv_buf.data());
+ byte_reader reader2(mod_recv_buf.data(), mod_recv_buf.size());
BLT_INFO("Bytes answered %d with %d answers", out_bytes, num_of_answers);