diff options
author | Jack Lloyd <[email protected]> | 2016-10-11 13:00:57 -0400 |
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committer | Jack Lloyd <[email protected]> | 2016-10-21 16:53:16 -0400 |
commit | 558808900bffc3c48da5e6d79ba602e88e619154 (patch) | |
tree | fd76ee2d009c2b707d888683cbd767351c4ff6b3 /src/lib/compression/compress_utils.cpp | |
parent | 6aa855bba613c7b6fedfbe71d15930964acb1633 (diff) |
Remove Algo_Registry
I repent my use of global constructors.
I repent my use of global locks.
Hopefully I will never touch this code again.
:)
Diffstat (limited to 'src/lib/compression/compress_utils.cpp')
-rw-r--r-- | src/lib/compression/compress_utils.cpp | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/src/lib/compression/compress_utils.cpp b/src/lib/compression/compress_utils.cpp new file mode 100644 index 000000000..2af629b9c --- /dev/null +++ b/src/lib/compression/compress_utils.cpp @@ -0,0 +1,189 @@ +/* +* Compression Utils +* (C) 2014,2016 Jack Lloyd +* +* Botan is released under the Simplified BSD License (see license.txt) +*/ + +#include <botan/internal/compress_utils.h> +#include <botan/exceptn.h> + +namespace Botan { + +void* Compression_Alloc_Info::do_malloc(size_t n, size_t size) + { + const size_t total_size = n * size; + + BOTAN_ASSERT_EQUAL(total_size / size, n, "Overflow check"); + + // TODO maximum length check here? + + void* ptr = std::malloc(total_size); + + /* + * Return null rather than throwing here as we are being called by a + * C library and it may not be possible for an exception to unwind + * the call stack from here. The compression library is expecting a + * function written in C and a null return on error, which it will + * send upwards to the compression wrappers. + */ + + if(ptr) + { + std::memset(ptr, 0, total_size); + m_current_allocs[ptr] = total_size; + } + + return ptr; + } + +void Compression_Alloc_Info::do_free(void* ptr) + { + if(ptr) + { + auto i = m_current_allocs.find(ptr); + + if(i == m_current_allocs.end()) + throw Exception("Compression_Alloc_Info::free got pointer not allocated by us"); + + zero_mem(ptr, i->second); + std::free(ptr); + m_current_allocs.erase(i); + } + } + +void Stream_Compression::clear() + { + m_stream.reset(); + } + +void Stream_Compression::start(size_t level) + { + m_stream.reset(make_stream(level)); + } + +void Stream_Compression::process(secure_vector<byte>& buf, size_t offset, u32bit flags) + { + BOTAN_ASSERT(m_stream, "Initialized"); + BOTAN_ASSERT(buf.size() >= offset, "Offset is sane"); + + if(m_buffer.size() < buf.size() + offset) + m_buffer.resize(buf.size() + offset); + + // If the output buffer has zero length, .data() might return nullptr. This would + // make some compression algorithms (notably those provided by zlib) fail. + // Any small positive value works fine, but we choose 32 as it is the smallest power + // of two that is large enough to hold all the headers and trailers of the common + // formats, preventing further resizings to make room for output data. + if(m_buffer.size() == 0) + m_buffer.resize(32); + + m_stream->next_in(buf.data() + offset, buf.size() - offset); + m_stream->next_out(m_buffer.data() + offset, m_buffer.size() - offset); + + while(true) + { + m_stream->run(flags); + + if(m_stream->avail_out() == 0) + { + const size_t added = 8 + m_buffer.size(); + m_buffer.resize(m_buffer.size() + added); + m_stream->next_out(m_buffer.data() + m_buffer.size() - added, added); + } + else if(m_stream->avail_in() == 0) + { + m_buffer.resize(m_buffer.size() - m_stream->avail_out()); + break; + } + } + + copy_mem(m_buffer.data(), buf.data(), offset); + buf.swap(m_buffer); + } + +void Stream_Compression::update(secure_vector<byte>& buf, size_t offset, bool flush) + { + BOTAN_ASSERT(m_stream, "Initialized"); + process(buf, offset, flush ? m_stream->flush_flag() : m_stream->run_flag()); + } + +void Stream_Compression::finish(secure_vector<byte>& buf, size_t offset) + { + BOTAN_ASSERT(m_stream, "Initialized"); + process(buf, offset, m_stream->finish_flag()); + clear(); + } + +void Stream_Decompression::clear() + { + m_stream.reset(); + } + +void Stream_Decompression::start() + { + m_stream.reset(make_stream()); + } + +void Stream_Decompression::process(secure_vector<byte>& buf, size_t offset, u32bit flags) + { + BOTAN_ASSERT(m_stream, "Initialized"); + BOTAN_ASSERT(buf.size() >= offset, "Offset is sane"); + + if(m_buffer.size() < buf.size() + offset) + m_buffer.resize(buf.size() + offset); + + m_stream->next_in(buf.data() + offset, buf.size() - offset); + m_stream->next_out(m_buffer.data() + offset, m_buffer.size() - offset); + + while(true) + { + const bool stream_end = m_stream->run(flags); + + if(stream_end) + { + if(m_stream->avail_in() == 0) // all data consumed? + { + m_buffer.resize(m_buffer.size() - m_stream->avail_out()); + clear(); + break; + } + + // More data follows: try to process as a following stream + const size_t read = (buf.size() - offset) - m_stream->avail_in(); + start(); + m_stream->next_in(buf.data() + offset + read, buf.size() - offset - read); + } + + if(m_stream->avail_out() == 0) + { + const size_t added = 8 + m_buffer.size(); + m_buffer.resize(m_buffer.size() + added); + m_stream->next_out(m_buffer.data() + m_buffer.size() - added, added); + } + else if(m_stream->avail_in() == 0) + { + m_buffer.resize(m_buffer.size() - m_stream->avail_out()); + break; + } + } + + copy_mem(m_buffer.data(), buf.data(), offset); + buf.swap(m_buffer); + } + +void Stream_Decompression::update(secure_vector<byte>& buf, size_t offset) + { + process(buf, offset, m_stream->run_flag()); + } + +void Stream_Decompression::finish(secure_vector<byte>& buf, size_t offset) + { + if(buf.size() != offset || m_stream.get()) + process(buf, offset, m_stream->finish_flag()); + + if(m_stream.get()) + throw Exception(name() + " finished but not at stream end"); + } + +} |