TON Storage utilities (#564)

* Rename chunk to piece in MerkleTree for consistency

* Refactor PeerManager

* Make PeerState thread-safe

* Download torrent by hash

* First version of storage daemon

* Download torrents partially

* Improve storing and loading torrent state in DB

* Rewrite MerkleTree

* "Remove torrent" in storage daemon

* Process errors, fix bugs in storage

* Move TonlibClientWrapper from rldp-http-proxy to tonlib

* Initial version of storage provider

* Move interaction with contracts to smc-util

* Improve TonlibClientWrapper interface

* Various improvements in storage provider

* Fix TorrentCreator.cpp

* Improve interface for partial download

* Client mode in storage-daemon

* Improve interface of storage-daemon-cli

* Fix calculating speed, show peers in storage-daemon

* Use permanent adnl id in storage daemon

* Fix sending large "storage.addUpdate" messages

* Improve printing torrents in cli

* Update tlo

* Fix RldpSender::on_ack

* Update storage provider

* Add "address" parameter to get-provider-params

* Allow client to close storage contract

* Limit torrent description

* Add more logs to storage provider

* smc.forget tonlib method

* Use smc.forget in storage daemon

* Optimize sending messages in smc-util.cpp

* Fix verbosity, remove excessive logs

* Json output in storage-daemon-cli

* Update storage provider contracts

* Fix rldp2 acks

* Change verbosity of logs in rldp2

* Update help and output of commands and in storage-daemon-cli

Co-authored-by: SpyCheese <mikle98@yandex.ru>

storage/TorrentHeader.cpp

@@ -66,4 +66,76 @@ td::Slice TorrentHeader::get_name(td::uint64 file_i) const {
   return td::Slice(names).substr(from, till - from);
 }
 
+static td::Status validate_name(td::Slice name, bool is_dir_name = false) {
+  if (name.empty()) {
+    return td::Status::Error("Name can't be empty");
+  }
+  if (name[0] == '/') {
+    return td::Status::Error("Name can't start with '/'");
+  }
+  if (name.back() == '/' && !is_dir_name) {
+    return td::Status::Error("Name can't end with '/'");
+  }
+  for (size_t l = 0; l < name.size();) {
+    size_t r = l + 1;
+    while (r < name.size() && name[r] != '/') {
+      ++r;
+    }
+    td::Slice s = name.substr(l, r - l);
+    if (s == "") {
+      return td::Status::Error("Name can't contain consequitive '/'");
+    }
+    if (s == ".") {
+      return td::Status::Error("Name can't contain component \".\"");
+    }
+    if (s == "..") {
+      return td::Status::Error("Name can't contain component \"..\"");
+    }
+    l = r + 1;
+  }
+  return td::Status::OK();
+}
+
+td::Status TorrentHeader::validate(td::uint64 total_size, td::uint64 header_size) const {
+  if (serialization_size() != header_size) {
+    return td::Status::Error("Invalid size");
+  }
+  for (size_t i = 0; i + 1 < files_count; ++i) {
+    if (name_index[i] > name_index[i + 1]) {
+      return td::Status::Error("Invalid name offset");
+    }
+  }
+  if (name_index.back() != names.size()) {
+    return td::Status::Error("Invalid name offset");
+  }
+  for (size_t i = 0; i < files_count; ++i) {
+    if (get_data_offset(i) > get_data_offset(i + 1)) {
+      return td::Status::Error("Invalid data offset");
+    }
+  }
+  if (get_data_offset(files_count) != total_size) {
+    return td::Status::Error("Invalid data offset");
+  }
+
+  std::set<std::string> names;
+  for (size_t i = 0; i < files_count; ++i) {
+    auto name = get_name(i);
+    TRY_STATUS_PREFIX(validate_name(name), PSTRING() << "Invalid filename " << name << ": ");
+    if (!names.insert(name.str()).second) {
+      return td::Status::Error(PSTRING() << "Duplicate filename " << name);
+    }
+  }
+  if (!dir_name.empty()) {
+    TRY_STATUS_PREFIX(validate_name(dir_name, true), "Invalid dir_name: ");
+  }
+  for (const std::string& name : names) {
+    std::string name1 = name + '/';
+    auto it = names.lower_bound(name1);
+    if (it != names.end() && it->substr(0, name1.size()) == name1) {
+      return td::Status::Error(PSTRING() << "Filename " << name << " coincides with directory name");
+    }
+  }
+  return td::Status::OK();
+}
+
 }  // namespace ton