A performant ASN.1 BER encoding and decoding library written in C++11
fast_ber is a small, lightweight library for BER encoding and decoding. Fast ber forgoes some tight ASN.1 specification conformance to provide fast encoding and decoding performance in common use cases
Read more about the decisions made writing this library
fast_ber_view can be used to dump the contents of a BER PDU, without requiring a schema.
./build/src/fast_ber_view ./build_gcc/sample/pokemon.ber | jq
{
"length": 125,
"identifier": {
"class": "Universal",
"tag": "Sequence / Sequence Of"
},
"content": ...
}
Test data is wanted to improve this project! If you have any test ASN.1 specs or BER files please share them. More test data will improve parsing and help find any issues with the library.
fast_ber
is designed to be easy to consume via CMake. This is demonstrated in fast_ber_ldap3
, an example project using fast_ber
to create and dissect LDAP3 certificates.
git submodule update --init
mkdir build_cmake
cd build_cmake
cmake ..
make
ctest
Pokemon DEFINITIONS EXPLICIT TAGS ::= BEGIN
Team ::= SEQUENCE {
team-name OCTET STRING,
members SEQUENCE OF Pokemon
}
Pokemon ::= SEQUENCE {
name OCTET STRING,
category OCTET STRING,
type Type,
ability OCTET STRING,
weakness OCTET STRING,
weight INTEGER
}
Type ::= ENUMERATED {
normal,
fire,
fighting,
water,
flying,
grass
}
END
cd build_cmake
./src/fast_ber_compiler pokemon.asn pokemon
output:
#pragma once
#include "fast_ber/ber_types/All.hpp"
#include "pokemon.fwd.hpp"
namespace fast_ber {
using namespace abbreviations;
namespace Pokemon {
enum class TypeValues {
normal,
fire,
fighting,
water,
flying,
grass,
};
template <typename Identifier>
FAST_BER_ALIAS(Type, Enumerated<TypeValues>);
template <typename Identifier>
struct Pokemon {
OctetString<> name;
OctetString<> category;
Type<> type;
OctetString<> ability;
OctetString<> weakness;
Integer<> weight;
};
template <typename Identifier>
struct Team {
OctetString<> team_name;
SequenceOf<Pokemon<>> members;
};
} // End namespace Pokemon
} // End namespace fast_ber
#include "pokemon.hpp"
int main()
{
fast_ber::Pokemon::Team<> team = {"Sam's Team"};
fast_ber::Pokemon::Pokemon<> muchlax = { "Munchlax",
"Big Eater",
fast_ber::Pokemon::Type<>::Values::normal,
"Thick Fat, Pickup",
"Fighting",
105 };
fast_ber::Pokemon::Pokemon<> piplup = { "Piplup",
"Penguin",
fast_ber::Pokemon::Type<>::Values::water,
Torrent",
"Electric, Grass",
12 };
team.members.push_back(muchlax);
team.members.push_back(piplup);
std::array<uint8_t, 2000> buffer{};
const auto encode_result = fast_ber::encode(absl::Span<uint8_t>(buffer), team);
if (!encode_result.success)
{
return -1;
}
return 0;
}
Take a look at fast_ber_ldap3
for an example of these steps in action.
fast_ber is in development. The following table documents what has been implemented and what features are coming soon
Type | Implemented |
---|---|
Integer | Yes |
Boolean | Yes |
Strings | Yes |
Sequence | Yes |
Sequence Of | Yes |
Choice | Yes |
Set | No |
Set Of | Yes |
Enumerated | Yes |
Object Identifier | Yes |
Dates / Times | No |
Null | Yes |
Any | No |
Feature | Implemented |
---|---|
Explicit tags | Yes |
Implicit tags | Yes |
Indefinitive length | No |
Arbitrary top level structure | Yes |
Arbritary definition order | Yes |
Embedded Types | Yes |
Imports | Yes |
The following features may be added in the future
Partial decoding
Partial encode at compile time (templated / constexpr)
High / low conformance modes
DER mode
fast_ber includes benchmarks against asn1c, an ASN library written in C. Here is an example of the output:
-------------------------------------------------------------------------------
Benchmark: Decode Performance
-------------------------------------------------------------------------------
...............................................................................
benchmark name iters elapsed ns average
-------------------------------------------------------------------------------
fast_ber - 1,000,000 x decode 2107B pdu 1 516381442 516.381 ms
asn1c - 1,000,000 x decode 2107B pdu 1 4996255249 4.99626 s
fast_ber - 1,000,000 x decode 64B pdu 1 192230063 192.23 ms
asn1c - 1,000,000 x decode 64B pdu 1 2581069031 2.58107 s
-------------------------------------------------------------------------------
Benchmark: Encode Performance
-------------------------------------------------------------------------------
...............................................................................
benchmark name iters elapsed ns average
-------------------------------------------------------------------------------
fast_ber - 1,000,000 x encode 2107B pdu 1 191266512 191.267 ms
asn1c - 1,000,000 x encode 2107B pdu 1 7349946740 7.34995 s
-------------------------------------------------------------------------------
Benchmark: Object Construction Performance
-------------------------------------------------------------------------------
...............................................................................
benchmark name iters elapsed ns average
-------------------------------------------------------------------------------
fast_ber - 1,000,000 x construct data 1 1005938231 1.00594 s
asn1c - 1,000,000 x construct data 1 511881940 511.882 ms
-------------------------------------------------------------------------------
Benchmark: Calculate Encoded Length Performance
-------------------------------------------------------------------------------
...............................................................................
benchmark name iters elapsed ns average
-------------------------------------------------------------------------------
fast_ber - 1,000,000 x encoded length 1 17084558 17.0846 ms
===============================================================================
All tests passed (31 assertions in 8 test cases)