1 files changed, 184 insertions, 0 deletions
diff --git a/controller/JSONDB.cpp b/controller/JSONDB.cpp
new file mode 100644
index 00000000..1277aabb
--- /dev/null
+++ b/controller/JSONDB.cpp
@@ -0,0 +1,184 @@
+/*
+ * ZeroTier One - Network Virtualization Everywhere
+ * Copyright (C) 2011-2015  ZeroTier, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "JSONDB.hpp"
+
+namespace ZeroTier {
+
+static const nlohmann::json _EMPTY_JSON(nlohmann::json::object());
+
+bool JSONDB::writeRaw(const std::string &n,const std::string &obj)
+{
+	if (!_isValidObjectName(n))
+		return false;
+
+	const std::string path(_genPath(n,true));
+	if (!path.length())
+		return false;
+
+	const std::string buf(obj);
+	if (!OSUtils::writeFile(path.c_str(),buf))
+		return false;
+
+	return true;
+}
+
+bool JSONDB::put(const std::string &n,const nlohmann::json &obj)
+{
+	if (!_isValidObjectName(n))
+		return false;
+
+	const std::string path(_genPath(n,true));
+	if (!path.length())
+		return false;
+
+	const std::string buf(OSUtils::jsonDump(obj));
+	if (!OSUtils::writeFile(path.c_str(),buf))
+		return false;
+
+	_E &e = _db[n];
+	e.obj = obj;
+	e.lastModifiedOnDisk = OSUtils::getLastModified(path.c_str());
+	e.lastCheck = OSUtils::now();
+
+	return true;
+}
+
+const nlohmann::json &JSONDB::get(const std::string &n,unsigned long maxSinceCheck)
+{
+	if (!_isValidObjectName(n))
+		return _EMPTY_JSON;
+
+	const uint64_t now = OSUtils::now();
+	std::string buf;
+	std::map<std::string,_E>::iterator e(_db.find(n));
+
+	if (e != _db.end()) {
+		if ((now - e->second.lastCheck) <= (uint64_t)maxSinceCheck)
+			return e->second.obj;
+
+		const std::string path(_genPath(n,false));
+		if (!path.length()) // sanity check
+			return _EMPTY_JSON;
+
+		// We are somewhat tolerant to momentary disk failures here. This may
+		// occur over e.g. EC2's elastic filesystem (NFS).
+		const uint64_t lm = OSUtils::getLastModified(path.c_str());
+		if (e->second.lastModifiedOnDisk != lm) {
+			if (OSUtils::readFile(path.c_str(),buf)) {
+				try {
+					e->second.obj = OSUtils::jsonParse(buf);
+					e->second.lastModifiedOnDisk = lm; // don't update these if there is a parse error -- try again and again ASAP
+					e->second.lastCheck = now;
+				} catch ( ... ) {} // parse errors result in "holding pattern" behavior
+			}
+		}
+
+		return e->second.obj;
+	} else {
+		const std::string path(_genPath(n,false));
+		if (!path.length())
+			return _EMPTY_JSON;
+
+		if (!OSUtils::readFile(path.c_str(),buf))
+			return _EMPTY_JSON;
+
+		const uint64_t lm = OSUtils::getLastModified(path.c_str());
+		_E &e2 = _db[n];
+		try {
+			e2.obj = OSUtils::jsonParse(buf);
+		} catch ( ... ) {
+			e2.obj = _EMPTY_JSON;
+			buf = "{}";
+		}
+		e2.lastModifiedOnDisk = lm;
+		e2.lastCheck = now;
+
+		return e2.obj;
+	}
+}
+
+void JSONDB::erase(const std::string &n)
+{
+	if (!_isValidObjectName(n))
+		return;
+
+	std::string path(_genPath(n,true));
+	if (!path.length())
+		return;
+
+	OSUtils::rm(path.c_str());
+	_db.erase(n);
+}
+
+void JSONDB::_reload(const std::string &p)
+{
+	std::map<std::string,char> l(OSUtils::listDirectoryFull(p.c_str()));
+	for(std::map<std::string,char>::iterator li(l.begin());li!=l.end();++li) {
+		if (li->second == 'f') {
+			// assume p starts with _basePath, which it always does -- will throw otherwise
+			std::string n(p.substr(_basePath.length()));
+			while ((n.length() > 0)&&(n[0] == ZT_PATH_SEPARATOR)) n = n.substr(1);
+			if (ZT_PATH_SEPARATOR != '/') std::replace(n.begin(),n.end(),ZT_PATH_SEPARATOR,'/');
+			if ((n.length() > 0)&&(n[n.length() - 1] != '/')) n.push_back('/');
+			n.append(li->first);
+			if ((n.length() > 5)&&(n.substr(n.length() - 5) == ".json")) {
+				this->get(n.substr(0,n.length() - 5),0); // causes load and cache or update
+			}
+		} else if (li->second == 'd') {
+			this->_reload(p + ZT_PATH_SEPARATOR + li->first);
+		}
+	}
+}
+
+bool JSONDB::_isValidObjectName(const std::string &n)
+{
+	if (n.length() == 0)
+		return false;
+	const char *p = n.c_str();
+	char c;
+	// For security reasons we should not allow dots, backslashes, or other path characters or potential path characters.
+	while ((c = *(p++))) {
+		if (!( ((c >= 'a')&&(c <= 'z')) || ((c >= 'A')&&(c <= 'Z')) || ((c >= '0')&&(c <= '9')) || (c == '/') || (c == '_') || (c == '~') || (c == '-') ))
+			return false;
+	}
+	return true;
+}
+
+std::string JSONDB::_genPath(const std::string &n,bool create)
+{
+	std::vector<std::string> pt(OSUtils::split(n.c_str(),"/","",""));
+	if (pt.size() == 0)
+		return std::string();
+
+	std::string p(_basePath);
+	if (create) OSUtils::mkdir(p.c_str());
+	for(unsigned long i=0,j=(unsigned long)(pt.size()-1);i<j;++i) {
+		p.push_back(ZT_PATH_SEPARATOR);
+		p.append(pt[i]);
+		if (create) OSUtils::mkdir(p.c_str());
+	}
+
+	p.push_back(ZT_PATH_SEPARATOR);
+	p.append(pt[pt.size()-1]);
+	p.append(".json");
+
+	return p;
+}
+
+} // namespace ZeroTier