Index: net/base/pem_tokenizer.cc |
diff --git a/net/base/pem_tokenizer.cc b/net/base/pem_tokenizer.cc |
new file mode 100644 |
index 0000000000000000000000000000000000000000..0abe5dbd5546fe5e5f1339c349b63c67150daecb |
--- /dev/null |
+++ b/net/base/pem_tokenizer.cc |
@@ -0,0 +1,95 @@ |
+// Copyright (c) 2010 The Chromium Authors. All rights reserved. |
+// Use of this source code is governed by a BSD-style license that can be |
+// found in the LICENSE file. |
+ |
+#include "net/base/pem_tokenizer.h" |
+ |
+#include "base/base64.h" |
+#include "base/string_util.h" |
+ |
+namespace { |
+ |
+const char kPEMSearchBlock[] = "-----BEGIN "; |
+const char kPEMBeginBlock[] = "-----BEGIN %s-----"; |
+const char kPEMEndBlock[] = "-----END %s-----"; |
+ |
+} // namespace |
+ |
+namespace net { |
+ |
+using base::StringPiece; |
+ |
+PEMTokenizer::PEMTokenizer( |
+ const StringPiece& str, |
+ const std::vector<std::string>& allowed_block_types) { |
+ Init(str, allowed_block_types); |
+} |
+ |
+bool PEMTokenizer::GetNext() { |
+ while (pos_ != StringPiece::npos) { |
+ // Scan for the beginning of the next PEM encoded block. |
+ pos_ = str_.find(kPEMSearchBlock, pos_); |
+ if (pos_ == StringPiece::npos) |
+ return false; // No more PEM blocks |
+ |
+ std::vector<PEMType>::const_iterator it; |
+ // Check to see if it is of an acceptable block type. |
+ for (it = block_types_.begin(); it != block_types_.end(); ++it) { |
+ if (!str_.substr(pos_).starts_with(it->header)) |
+ continue; |
+ |
+ // Look for a footer matching the header. If none is found, then all |
+ // data following this point is invalid and should not be parsed. |
+ StringPiece::size_type footer_pos = str_.find(it->footer, pos_); |
+ if (footer_pos == StringPiece::npos) { |
+ pos_ = StringPiece::npos; |
+ return false; |
+ } |
+ |
+ // Chop off the header and footer and parse the data in between. |
+ StringPiece::size_type data_begin = pos_ + it->header.size(); |
+ pos_ = footer_pos + it->footer.size(); |
+ block_type_ = it->type; |
+ |
+ StringPiece encoded = str_.substr(data_begin, |
+ footer_pos - data_begin); |
+ if (!base::Base64Decode(CollapseWhitespaceASCII(encoded.as_string(), |
+ true), &data_)) { |
+ // The most likely cause for a decode failure is a datatype that |
+ // includes PEM headers, which are not supported. |
+ break; |
+ } |
+ |
+ return true; |
+ } |
+ |
+ // If the block did not match any acceptable type, move past it and |
+ // continue the search. Otherwise, |pos_| has been updated to the most |
+ // appropriate search position to continue searching from and should not |
+ // be adjusted. |
+ if (it == block_types_.end()) |
+ pos_ += sizeof(kPEMSearchBlock); |
+ } |
+ |
+ return false; |
+} |
+ |
+void PEMTokenizer::Init( |
+ const StringPiece& str, |
+ const std::vector<std::string>& allowed_block_types) { |
+ str_ = str; |
+ pos_ = 0; |
+ |
+ // Construct PEM header/footer strings for all the accepted types, to |
+ // reduce parsing later. |
+ for (std::vector<std::string>::const_iterator it = |
+ allowed_block_types.begin(); it != allowed_block_types.end(); ++it) { |
+ PEMType allowed_type; |
+ allowed_type.type = *it; |
+ allowed_type.header = StringPrintf(kPEMBeginBlock, it->c_str()); |
+ allowed_type.footer = StringPrintf(kPEMEndBlock, it->c_str()); |
+ block_types_.push_back(allowed_type); |
+ } |
+} |
+ |
+} // namespace net |