[PATCH 04/07] Inject repo authorization filter. Provide sample for gitolite integration.

[ranger at risk.ee (The Ranger)]

---
 filters/gitolite-authorization.lua | 74 ++++++++++++++++++++++++++++++++++++++
 scan-tree.c                        | 18 ++++++++++
 2 files changed, 92 insertions(+)
 create mode 100644 filters/gitolite-authorization.lua

diff --git a/filters/gitolite-authorization.lua b/filters/gitolite-authorization.lua
new file mode 100644
index 0000000..2f0e4f5
--- /dev/null
+++ b/filters/gitolite-authorization.lua
@@ -0,0 +1,74 @@
+-- This script can be used with project-filter option
+-- It uses REMOTE_USER environment variable to obtain the user who needs to be authorized
+-- This variable is normally set by HTTP Basic Authentication.
+-- In Apache something like this can be used:
+--
+--    AuthType Basic
+--    AuthName Protected area
+--    AuthUserFile users.htpasswd
+--    Require valid-user
+--
+-- For anonymous access a public username can be set in environment config.
+-- In Apache, using mod_env:
+--
+--    SetEnv REMOTE_USER gitweb
+--
+-- Gitolite requires HOME environment variable to work properly and point to valid Gitolite
+-- environment. Since the user, under which web server process runs, usually does not have
+-- this set, HOME should be explicitly configured and pointed to valid gitolite setup.
+-- In Apache, using mod_env:
+--
+--    SetEnv HOME /path/to/gitolite/home
+
+
+local git = {}
+local http = {}
+local repos = {}
+local action = nil
+
+function action_init()
+	-- Anonymous access, cancel repo list building
+	if git.user == nil or git.user == "" then return end
+	
+	local handle = io.popen("gitolite list-phy-repos | gitolite access % " .. git.user .. " R any")
+	
+	while true do
+		local repo = handle:read()
+		if repo == nil then break end
+		
+		-- Skip DENIED repos
+		if not string.find(repo, "DENIED") then
+			-- Gitolite returns string: <repo>\t<user>\t<refs>
+			-- We are interested only in the first field for now
+			-- Append .git extension since Gitolite does not and cgit repo name has it
+			local name = string.sub(repo, 0, string.find(repo, "\t") - 1) .. ".git"
+			repos[name] = 1 -- Authorize flag is > 0
+		end
+	end
+	
+	handle:close()
+end
+
+function action_filter()
+	-- Return > 0 if access is authorized
+	return repos[git.repo]
+end
+
+local actions = {}
+actions["init"] = action_init;
+actions["filter"] = action_filter;
+
+function filter_open(...)
+	action = actions[select(1, ...)]
+	
+	git["repo"] = select(2, ...)
+	git["user"] = select(3, ...)
+	
+	http["server"] = select(4, ...)
+	http["path"] = select(5, ...)
+end
+
+function filter_close()
+	return action()
+end
+
diff --git a/scan-tree.c b/scan-tree.c
index e17bca9..7490e74 100644
--- a/scan-tree.c
+++ b/scan-tree.c
@@ -74,6 +74,14 @@ static char *xstrrchr(char *s, char *from, int c)
 	return from < s ? NULL : from;
 }
 
+static int open_project_filter(const char *action, const char *repo) {
+	return cgit_open_filter(ctx.cfg.project_filter, action, repo,
+			ctx.env.remote_user ? ctx.env.remote_user : "",
+			ctx.env.server_name ? ctx.env.server_name : "",
+			ctx.env.path_info ? ctx.env.path_info : ""
+	);
+}
+
 static void add_repo(const char *base, struct strbuf *path, repo_config_fn fn)
 {
 	struct stat st;
@@ -115,6 +123,11 @@ static void add_repo(const char *base, struct strbuf *path, repo_config_fn fn)
 	else if (rel.len && rel.buf[rel.len - 1] == '/')
 		strbuf_setlen(&rel, rel.len - 1);
 
+	if(ctx.cfg.project_filter) {
+		if(open_project_filter("filter", rel.buf)) return;
+		if(cgit_close_filter(ctx.cfg.project_filter) < 1) return;
+	}
+
 	repo = cgit_add_repo(rel.buf);
 	config_fn = fn;
 	if (ctx.cfg.enable_git_config) {
@@ -261,6 +274,11 @@ void scan_projects(const char *path, const char *projectsfile, repo_config_fn fn
 
 void scan_tree(const char *path, repo_config_fn fn)
 {
+	if (ctx.cfg.project_filter) {
+		open_project_filter("init", path);
+		cgit_close_filter(ctx.cfg.project_filter);
+	}
+
 	if (ctx.cfg.project_list) {
 		scan_projects(path, ctx.cfg.project_list, fn);
 		return;
-- 
2.1.4