wallet: wipe seed from memory where appropriate

contrib/epee/include/fnv1.h

@@ -0,0 +1,45 @@
+// Copyright (c) 2018, The Monero Project
+// 
+// All rights reserved.
+// 
+// Redistribution and use in source and binary forms, with or without modification, are
+// permitted provided that the following conditions are met:
+// 
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//    conditions and the following disclaimer.
+// 
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list
+//    of conditions and the following disclaimer in the documentation and/or other
+//    materials provided with the distribution.
+// 
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//    used to endorse or promote products derived from this software without specific
+//    prior written permission.
+// 
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#pragma once
+
+namespace epee
+{
+
+namespace fnv
+{
+  inline uint64_t FNV1a(const char *ptr, size_t sz)
+  {
+    uint64_t h = 0xcbf29ce484222325;
+    for (size_t i = 0; i < sz; ++i)
+      h = (h ^ *(const uint8_t*)ptr++) * 0x100000001b3;
+    return h;
+  }
+}
+
+}

contrib/epee/include/hex.h

@@ -33,6 +33,7 @@
 #include <iosfwd>
 #include <string>
 
+#include "wipeable_string.h"
 #include "span.h"
 
 namespace epee
@@ -41,6 +42,8 @@ namespace epee
   {
     //! \return A std::string containing hex of `src`.
     static std::string string(const span<const std::uint8_t> src);
+    //! \return A epee::wipeable_string containing hex of `src`.
+    static epee::wipeable_string wipeable_string(const span<const std::uint8_t> src);
 
     //! \return An array containing hex of `src`.
     template<std::size_t N>
@@ -59,6 +62,8 @@ namespace epee
     static void formatted(std::ostream& out, const span<const std::uint8_t> src);
 
   private:
+    template<typename T> T static convert(const span<const std::uint8_t> src);
+
     //! Write `src` bytes as hex to `out`. `out` must be twice the length
     static void buffer_unchecked(char* out, const span<const std::uint8_t> src) noexcept;
   };

contrib/epee/include/wipeable_string.h

@@ -28,28 +28,43 @@
 
 #pragma once
 
+#include <boost/optional/optional_fwd.hpp>
 #include <stddef.h>
 #include <vector>
 #include <string>
+#include "fnv1.h"
 
 namespace epee
 {
   class wipeable_string
   {
   public:
+    typedef char value_type;
+
     wipeable_string() {}
     wipeable_string(const wipeable_string &other);
     wipeable_string(wipeable_string &&other);
     wipeable_string(const std::string &other);
     wipeable_string(std::string &&other);
     wipeable_string(const char *s);
+    wipeable_string(const char *s, size_t len);
     ~wipeable_string();
     void wipe();
     void push_back(char c);
-    void pop_back();
+    void operator+=(char c);
+    void operator+=(const std::string &s);
+    void operator+=(const epee::wipeable_string &s);
+    void operator+=(const char *s);
+    void append(const char *ptr, size_t len);
+    char pop_back();
     const char *data() const noexcept { return buffer.data(); }
+    char *data() noexcept { return buffer.data(); }
     size_t size() const noexcept { return buffer.size(); }
+    size_t length() const noexcept { return buffer.size(); }
     bool empty() const noexcept { return buffer.empty(); }
+    void trim();
+    void split(std::vector<wipeable_string> &fields) const;
+    boost::optional<wipeable_string> parse_hexstr() const;
     void resize(size_t sz);
     void reserve(size_t sz);
     void clear();
@@ -65,3 +80,14 @@ namespace epee
     std::vector<char> buffer;
   };
 }
+
+namespace std
+{
+  template<> struct hash<epee::wipeable_string>
+  {
+    size_t operator()(const epee::wipeable_string &s) const
+    {
+      return epee::fnv::FNV1a(s.data(), s.size());
+    }
+  };
+}