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-rw-r--r--botan/src/asn1/ber_dec.cpp471
1 files changed, 0 insertions, 471 deletions
diff --git a/botan/src/asn1/ber_dec.cpp b/botan/src/asn1/ber_dec.cpp
deleted file mode 100644
index ce60466..0000000
--- a/botan/src/asn1/ber_dec.cpp
+++ /dev/null
@@ -1,471 +0,0 @@
-/*
-* BER Decoder
-* (C) 1999-2008 Jack Lloyd
-*
-* Distributed under the terms of the Botan license
-*/
-
-#include <botan/ber_dec.h>
-#include <botan/bigint.h>
-#include <botan/loadstor.h>
-
-namespace Botan {
-
-namespace {
-
-/*
-* BER decode an ASN.1 type tag
-*/
-u32bit decode_tag(DataSource* ber, ASN1_Tag& type_tag, ASN1_Tag& class_tag)
- {
- byte b;
- if(!ber->read_byte(b))
- {
- class_tag = type_tag = NO_OBJECT;
- return 0;
- }
-
- if((b & 0x1F) != 0x1F)
- {
- type_tag = ASN1_Tag(b & 0x1F);
- class_tag = ASN1_Tag(b & 0xE0);
- return 1;
- }
-
- u32bit tag_bytes = 1;
- class_tag = ASN1_Tag(b & 0xE0);
-
- u32bit tag_buf = 0;
- while(true)
- {
- if(!ber->read_byte(b))
- throw BER_Decoding_Error("Long-form tag truncated");
- if(tag_buf & 0xFF000000)
- throw BER_Decoding_Error("Long-form tag overflowed 32 bits");
- ++tag_bytes;
- tag_buf = (tag_buf << 7) | (b & 0x7F);
- if((b & 0x80) == 0) break;
- }
- type_tag = ASN1_Tag(tag_buf);
- return tag_bytes;
- }
-
-/*
-* Find the EOC marker
-*/
-u32bit find_eoc(DataSource*);
-
-/*
-* BER decode an ASN.1 length field
-*/
-u32bit decode_length(DataSource* ber, u32bit& field_size)
- {
- byte b;
- if(!ber->read_byte(b))
- throw BER_Decoding_Error("Length field not found");
- field_size = 1;
- if((b & 0x80) == 0)
- return b;
-
- field_size += (b & 0x7F);
- if(field_size == 1) return find_eoc(ber);
- if(field_size > 5)
- throw BER_Decoding_Error("Length field is too large");
-
- u32bit length = 0;
-
- for(u32bit j = 0; j != field_size - 1; ++j)
- {
- if(get_byte(0, length) != 0)
- throw BER_Decoding_Error("Field length overflow");
- if(!ber->read_byte(b))
- throw BER_Decoding_Error("Corrupted length field");
- length = (length << 8) | b;
- }
- return length;
- }
-
-/*
-* BER decode an ASN.1 length field
-*/
-u32bit decode_length(DataSource* ber)
- {
- u32bit dummy;
- return decode_length(ber, dummy);
- }
-
-/*
-* Find the EOC marker
-*/
-u32bit find_eoc(DataSource* ber)
- {
- SecureVector<byte> buffer(DEFAULT_BUFFERSIZE), data;
-
- while(true)
- {
- const u32bit got = ber->peek(buffer, buffer.size(), data.size());
- if(got == 0)
- break;
- data.append(buffer, got);
- }
-
- DataSource_Memory source(data);
- data.destroy();
-
- u32bit length = 0;
- while(true)
- {
- ASN1_Tag type_tag, class_tag;
- u32bit tag_size = decode_tag(&source, type_tag, class_tag);
- if(type_tag == NO_OBJECT)
- break;
-
- u32bit length_size = 0;
- u32bit item_size = decode_length(&source, length_size);
- source.discard_next(item_size);
-
- length += item_size + length_size + tag_size;
-
- if(type_tag == EOC)
- break;
- }
- return length;
- }
-
-}
-
-/*
-* Check a type invariant on BER data
-*/
-void BER_Object::assert_is_a(ASN1_Tag type_tag, ASN1_Tag class_tag)
- {
- if(this->type_tag != type_tag || this->class_tag != class_tag)
- throw BER_Decoding_Error("Tag mismatch when decoding");
- }
-
-/*
-* Check if more objects are there
-*/
-bool BER_Decoder::more_items() const
- {
- if(source->end_of_data() && (pushed.type_tag == NO_OBJECT))
- return false;
- return true;
- }
-
-/*
-* Verify that no bytes remain in the source
-*/
-BER_Decoder& BER_Decoder::verify_end()
- {
- if(!source->end_of_data() || (pushed.type_tag != NO_OBJECT))
- throw Invalid_State("BER_Decoder::verify_end called, but data remains");
- return (*this);
- }
-
-/*
-* Save all the bytes remaining in the source
-*/
-BER_Decoder& BER_Decoder::raw_bytes(MemoryRegion<byte>& out)
- {
- out.destroy();
- byte buf;
- while(source->read_byte(buf))
- out.append(buf);
- return (*this);
- }
-
-/*
-* Discard all the bytes remaining in the source
-*/
-BER_Decoder& BER_Decoder::discard_remaining()
- {
- byte buf;
- while(source->read_byte(buf))
- ;
- return (*this);
- }
-
-/*
-* Return the BER encoding of the next object
-*/
-BER_Object BER_Decoder::get_next_object()
- {
- BER_Object next;
-
- if(pushed.type_tag != NO_OBJECT)
- {
- next = pushed;
- pushed.class_tag = pushed.type_tag = NO_OBJECT;
- return next;
- }
-
- decode_tag(source, next.type_tag, next.class_tag);
- if(next.type_tag == NO_OBJECT)
- return next;
-
- u32bit length = decode_length(source);
- next.value.create(length);
- if(source->read(next.value, length) != length)
- throw BER_Decoding_Error("Value truncated");
-
- if(next.type_tag == EOC && next.class_tag == UNIVERSAL)
- return get_next_object();
-
- return next;
- }
-
-/*
-* Push a object back into the stream
-*/
-void BER_Decoder::push_back(const BER_Object& obj)
- {
- if(pushed.type_tag != NO_OBJECT)
- throw Invalid_State("BER_Decoder: Only one push back is allowed");
- pushed = obj;
- }
-
-/*
-* Begin decoding a CONSTRUCTED type
-*/
-BER_Decoder BER_Decoder::start_cons(ASN1_Tag type_tag,
- ASN1_Tag class_tag)
- {
- BER_Object obj = get_next_object();
- obj.assert_is_a(type_tag, ASN1_Tag(class_tag | CONSTRUCTED));
-
- BER_Decoder result(obj.value, obj.value.size());
- result.parent = this;
- return result;
- }
-
-/*
-* Finish decoding a CONSTRUCTED type
-*/
-BER_Decoder& BER_Decoder::end_cons()
- {
- if(!parent)
- throw Invalid_State("BER_Decoder::end_cons called with NULL parent");
- if(!source->end_of_data())
- throw Decoding_Error("BER_Decoder::end_cons called with data left");
- return (*parent);
- }
-
-/*
-* BER_Decoder Constructor
-*/
-BER_Decoder::BER_Decoder(DataSource& src)
- {
- source = &src;
- owns = false;
- pushed.type_tag = pushed.class_tag = NO_OBJECT;
- parent = 0;
- }
-
-/*
-* BER_Decoder Constructor
- */
-BER_Decoder::BER_Decoder(const byte data[], u32bit length)
- {
- source = new DataSource_Memory(data, length);
- owns = true;
- pushed.type_tag = pushed.class_tag = NO_OBJECT;
- parent = 0;
- }
-
-/*
-* BER_Decoder Constructor
-*/
-BER_Decoder::BER_Decoder(const MemoryRegion<byte>& data)
- {
- source = new DataSource_Memory(data);
- owns = true;
- pushed.type_tag = pushed.class_tag = NO_OBJECT;
- parent = 0;
- }
-
-/*
-* BER_Decoder Copy Constructor
-*/
-BER_Decoder::BER_Decoder(const BER_Decoder& other)
- {
- source = other.source;
- owns = false;
- if(other.owns)
- {
- other.owns = false;
- owns = true;
- }
- pushed.type_tag = pushed.class_tag = NO_OBJECT;
- parent = other.parent;
- }
-
-/*
-* BER_Decoder Destructor
-*/
-BER_Decoder::~BER_Decoder()
- {
- if(owns)
- delete source;
- source = 0;
- }
-
-/*
-* Request for an object to decode itself
-*/
-BER_Decoder& BER_Decoder::decode(ASN1_Object& obj)
- {
- obj.decode_from(*this);
- return (*this);
- }
-
-/*
-* Decode a BER encoded NULL
-*/
-BER_Decoder& BER_Decoder::decode_null()
- {
- BER_Object obj = get_next_object();
- obj.assert_is_a(NULL_TAG, UNIVERSAL);
- if(obj.value.size())
- throw BER_Decoding_Error("NULL object had nonzero size");
- return (*this);
- }
-
-/*
-* Decode a BER encoded BOOLEAN
-*/
-BER_Decoder& BER_Decoder::decode(bool& out)
- {
- return decode(out, BOOLEAN, UNIVERSAL);
- }
-
-/*
-* Decode a small BER encoded INTEGER
-*/
-BER_Decoder& BER_Decoder::decode(u32bit& out)
- {
- return decode(out, INTEGER, UNIVERSAL);
- }
-
-/*
-* Decode a BER encoded INTEGER
-*/
-BER_Decoder& BER_Decoder::decode(BigInt& out)
- {
- return decode(out, INTEGER, UNIVERSAL);
- }
-
-/*
-* Decode a BER encoded BOOLEAN
-*/
-BER_Decoder& BER_Decoder::decode(bool& out,
- ASN1_Tag type_tag, ASN1_Tag class_tag)
- {
- BER_Object obj = get_next_object();
- obj.assert_is_a(type_tag, class_tag);
-
- if(obj.value.size() != 1)
- throw BER_Decoding_Error("BER boolean value had invalid size");
-
- out = (obj.value[0]) ? true : false;
- return (*this);
- }
-
-/*
-* Decode a small BER encoded INTEGER
-*/
-BER_Decoder& BER_Decoder::decode(u32bit& out,
- ASN1_Tag type_tag, ASN1_Tag class_tag)
- {
- BigInt integer;
- decode(integer, type_tag, class_tag);
- out = integer.to_u32bit();
- return (*this);
- }
-
-/*
-* Decode a BER encoded INTEGER
-*/
-BER_Decoder& BER_Decoder::decode(BigInt& out,
- ASN1_Tag type_tag, ASN1_Tag class_tag)
- {
- BER_Object obj = get_next_object();
- obj.assert_is_a(type_tag, class_tag);
-
- if(obj.value.is_empty())
- out = 0;
- else
- {
- const bool negative = (obj.value[0] & 0x80) ? true : false;
-
- if(negative)
- {
- for(u32bit j = obj.value.size(); j > 0; --j)
- if(obj.value[j-1]--)
- break;
- for(u32bit j = 0; j != obj.value.size(); ++j)
- obj.value[j] = ~obj.value[j];
- }
-
- out = BigInt(obj.value, obj.value.size());
-
- if(negative)
- out.flip_sign();
- }
-
- return (*this);
- }
-
-/*
-* BER decode a BIT STRING or OCTET STRING
-*/
-BER_Decoder& BER_Decoder::decode(MemoryRegion<byte>& out, ASN1_Tag real_type)
- {
- return decode(out, real_type, real_type, UNIVERSAL);
- }
-
-/*
-* BER decode a BIT STRING or OCTET STRING
-*/
-BER_Decoder& BER_Decoder::decode(MemoryRegion<byte>& buffer,
- ASN1_Tag real_type,
- ASN1_Tag type_tag, ASN1_Tag class_tag)
- {
- if(real_type != OCTET_STRING && real_type != BIT_STRING)
- throw BER_Bad_Tag("Bad tag for {BIT,OCTET} STRING", real_type);
-
- BER_Object obj = get_next_object();
- obj.assert_is_a(type_tag, class_tag);
-
- if(real_type == OCTET_STRING)
- buffer = obj.value;
- else
- {
- if(obj.value[0] >= 8)
- throw BER_Decoding_Error("Bad number of unused bits in BIT STRING");
- buffer.set(obj.value + 1, obj.value.size() - 1);
- }
- return (*this);
- }
-
-/*
-* Decode an OPTIONAL string type
-*/
-BER_Decoder& BER_Decoder::decode_optional_string(MemoryRegion<byte>& out,
- ASN1_Tag real_type,
- u16bit type_no)
- {
- BER_Object obj = get_next_object();
-
- ASN1_Tag type_tag = static_cast<ASN1_Tag>(type_no);
-
- out.clear();
- push_back(obj);
-
- if(obj.type_tag == type_tag && obj.class_tag == CONTEXT_SPECIFIC)
- decode(out, real_type, type_tag, CONTEXT_SPECIFIC);
-
- return (*this);
- }
-
-}