Source code
Revision control
Copy as Markdown
Other Tools
/*
* ASN.1 Internals
* (C) 1999-2007,2018 Jack Lloyd
*
* Botan is released under the Simplified BSD License (see license.txt)
*/
#include <botan/asn1_obj.h>
#include <botan/der_enc.h>
#include <botan/data_src.h>
#include <botan/internal/stl_util.h>
#include <sstream>
namespace Botan {
std::vector<uint8_t> ASN1_Object::BER_encode() const
{
std::vector<uint8_t> output;
DER_Encoder der(output);
this->encode_into(der);
return output;
}
/*
* Check a type invariant on BER data
*/
void BER_Object::assert_is_a(ASN1_Tag type_tag_, ASN1_Tag class_tag_,
const std::string& descr) const
{
if(this->is_a(type_tag_, class_tag_) == false)
{
std::stringstream msg;
msg << "Tag mismatch when decoding " << descr << " got ";
if(class_tag == NO_OBJECT && type_tag == NO_OBJECT)
{
msg << "EOF";
}
else
{
if(class_tag == UNIVERSAL || class_tag == CONSTRUCTED)
{
msg << asn1_tag_to_string(type_tag);
}
else
{
msg << std::to_string(type_tag);
}
msg << "/" << asn1_class_to_string(class_tag);
}
msg << " expected ";
if(class_tag_ == UNIVERSAL || class_tag_ == CONSTRUCTED)
{
msg << asn1_tag_to_string(type_tag_);
}
else
{
msg << std::to_string(type_tag_);
}
msg << "/" << asn1_class_to_string(class_tag_);
throw BER_Decoding_Error(msg.str());
}
}
bool BER_Object::is_a(ASN1_Tag type_tag_, ASN1_Tag class_tag_) const
{
return (type_tag == type_tag_ && class_tag == class_tag_);
}
bool BER_Object::is_a(int type_tag_, ASN1_Tag class_tag_) const
{
return is_a(ASN1_Tag(type_tag_), class_tag_);
}
void BER_Object::set_tagging(ASN1_Tag t, ASN1_Tag c)
{
type_tag = t;
class_tag = c;
}
std::string asn1_class_to_string(ASN1_Tag type)
{
switch(type)
{
case UNIVERSAL:
return "UNIVERSAL";
case CONSTRUCTED:
return "CONSTRUCTED";
case CONTEXT_SPECIFIC:
return "CONTEXT_SPECIFIC";
case APPLICATION:
return "APPLICATION";
case CONSTRUCTED | CONTEXT_SPECIFIC:
return "PRIVATE";
case Botan::NO_OBJECT:
return "NO_OBJECT";
default:
return "CLASS(" + std::to_string(static_cast<size_t>(type)) + ")";
}
}
std::string asn1_tag_to_string(ASN1_Tag type)
{
switch(type)
{
case Botan::SEQUENCE:
return "SEQUENCE";
case Botan::SET:
return "SET";
case Botan::PRINTABLE_STRING:
return "PRINTABLE STRING";
case Botan::NUMERIC_STRING:
return "NUMERIC STRING";
case Botan::IA5_STRING:
return "IA5 STRING";
case Botan::T61_STRING:
return "T61 STRING";
case Botan::UTF8_STRING:
return "UTF8 STRING";
case Botan::VISIBLE_STRING:
return "VISIBLE STRING";
case Botan::BMP_STRING:
return "BMP STRING";
case Botan::UNIVERSAL_STRING:
return "UNIVERSAL STRING";
case Botan::UTC_TIME:
return "UTC TIME";
case Botan::GENERALIZED_TIME:
return "GENERALIZED TIME";
case Botan::OCTET_STRING:
return "OCTET STRING";
case Botan::BIT_STRING:
return "BIT STRING";
case Botan::ENUMERATED:
return "ENUMERATED";
case Botan::INTEGER:
return "INTEGER";
case Botan::NULL_TAG:
return "NULL";
case Botan::OBJECT_ID:
return "OBJECT";
case Botan::BOOLEAN:
return "BOOLEAN";
case Botan::NO_OBJECT:
return "NO_OBJECT";
default:
return "TAG(" + std::to_string(static_cast<size_t>(type)) + ")";
}
}
/*
* BER Decoding Exceptions
*/
BER_Decoding_Error::BER_Decoding_Error(const std::string& str) :
Decoding_Error("BER: " + str) {}
BER_Bad_Tag::BER_Bad_Tag(const std::string& str, ASN1_Tag tag) :
BER_Decoding_Error(str + ": " + std::to_string(tag)) {}
BER_Bad_Tag::BER_Bad_Tag(const std::string& str,
ASN1_Tag tag1, ASN1_Tag tag2) :
BER_Decoding_Error(str + ": " + std::to_string(tag1) + "/" + std::to_string(tag2)) {}
namespace ASN1 {
/*
* Put some arbitrary bytes into a SEQUENCE
*/
std::vector<uint8_t> put_in_sequence(const std::vector<uint8_t>& contents)
{
return ASN1::put_in_sequence(contents.data(), contents.size());
}
std::vector<uint8_t> put_in_sequence(const uint8_t bits[], size_t len)
{
std::vector<uint8_t> output;
DER_Encoder(output)
.start_cons(SEQUENCE)
.raw_bytes(bits, len)
.end_cons();
return output;
}
/*
* Convert a BER object into a string object
*/
std::string to_string(const BER_Object& obj)
{
return std::string(cast_uint8_ptr_to_char(obj.bits()),
obj.length());
}
/*
* Do heuristic tests for BER data
*/
bool maybe_BER(DataSource& source)
{
uint8_t first_u8;
if(!source.peek_byte(first_u8))
{
BOTAN_ASSERT_EQUAL(source.read_byte(first_u8), 0, "Expected EOF");
throw Stream_IO_Error("ASN1::maybe_BER: Source was empty");
}
if(first_u8 == (SEQUENCE | CONSTRUCTED))
return true;
return false;
}
}
}