Add case conflict check

src/addon/client.cpp

@@ -220,6 +220,11 @@ bool addons_client::install_addon(config& archive_cfg, const addon_info& info)
 				"name and cannot be installed.", i18n_symbols));
 		return false;
 	}
+	if(!check_case_insensitive_duplicates(archive_cfg)){
+		gui2::show_error_message(v_,
+			vgettext("The add-on <i>$addon_title</i> has file or directory names "
+				"with case conflicts. This may cause problems.", i18n_symbols));
+	}
 
 	// Add local version information before unpacking
 

src/addon/validation.cpp

@@ -17,6 +17,8 @@
 #include "config.hpp"
 
 #include <algorithm>
+#include <boost/algorithm/string.hpp>
+#include <set>
 
 const unsigned short default_campaignd_port = 15008;
 
@@ -120,6 +122,23 @@ bool check_names_legal(const config& dir, std::vector<std::string>* badlist)
 	return check_names_legal_internal(dir, "", badlist);
 }
 
+bool check_case_insensitive_duplicates(const config& dir){
+	std::set<std::string> filenames;
+	bool inserted;
+	for (const config &path : dir.child_range("file")) {
+		const config::attribute_value &filename = path["name"];
+		std::tie(std::ignore, inserted) = filenames.insert(boost::algorithm::to_lower_copy(filename.str()));
+		if (!inserted) return false;
+	}
+	for (const config &path : dir.child_range("dir")) {
+		const config::attribute_value &filename = path["name"];
+		std::tie(std::ignore, inserted) = filenames.insert(boost::algorithm::to_lower_copy(filename.str()));
+		if (!inserted) return false;
+		if (!check_case_insensitive_duplicates(path)) return false;
+	}
+	return true;
+}
+
 ADDON_TYPE get_addon_type(const std::string& str)
 {
 	if (str.empty())

src/addon/validation.hpp

@@ -77,6 +77,8 @@ bool addon_filename_legal(const std::string& name);
  * @returns True if no illegal names were found.
  */
 bool check_names_legal(const config& dir, std::vector<std::string>* badlist = nullptr);
+/** Probes an add-on archive for case-conflicts on case-insensitive filesystems. */
+bool check_case_insensitive_duplicates(const config& dir);
 
 std::string encode_binary(const std::string& str);
 std::string unencode_binary(const std::string& str);

src/campaign_server/campaign_server.cpp

@@ -692,6 +692,9 @@ void server::handle_upload(const server::request& req)
 			"Add-on rejected: The add-on contains files or directories with illegal names. "
 			"File or directory names may not contain whitespace or any of the following characters: '/ \\ : ~'",
 			filelist, req.sock);
+	} else if(!check_case_insensitive_duplicates(data)) {
+		LOG_CS << "Upload aborted - case conflict in add-on data.\n";
+		send_error("Add-on rejected: Two files have a case conflict", req.sock);
 	} else if(campaign && !authenticate(*campaign, upload["passphrase"])) {
 		LOG_CS << "Upload aborted - incorrect passphrase.\n";
 		send_error("Add-on rejected: The add-on already exists, and your passphrase was incorrect.", req.sock);