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authorJack Lloyd <[email protected]>2016-10-11 13:00:57 -0400
committerJack Lloyd <[email protected]>2016-10-21 16:53:16 -0400
commit558808900bffc3c48da5e6d79ba602e88e619154 (patch)
treefd76ee2d009c2b707d888683cbd767351c4ff6b3 /src/lib/compression/compress_utils.cpp
parent6aa855bba613c7b6fedfbe71d15930964acb1633 (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.cpp189
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");
+ }
+
+}