Merge branch 'richardipsum/http' which contains the HTTP work from Richard

Ipsum done for Baserock but rebased to remove Baserock-specific content.

14 files changed, 756 insertions, 103 deletions

diff --git a/Makefile b/Makefile
index e81e4a3..7fa7d11 100644
--- a/Makefile
+++ b/Makefile
@@ -21,7 +21,8 @@ MAN_PATH := $(INST_ROOT)/share/man
 MAN_INST_PATH := $(DESTDIR)$(MAN_PATH)
 
 LIB_BINS := gitano-auth gitano-post-receive-hook gitano-update-hook	\
-	    gitano-update-ssh gitano-pre-receive-hook
+	    gitano-update-ssh gitano-pre-receive-hook gitano-smart-http.cgi \
+	    gitano-command.cgi
 
 BINS := gitano-setup
 
@@ -42,7 +43,7 @@ MODS := gitano 								\
 	gitano.actions gitano.config gitano.lace gitano.log		\
 	gitano.markdown gitano.repository gitano.supple 		\
 	gitano.command gitano.admincommand gitano.usercommand		\
-	gitano.repocommand gitano.copycommand
+	gitano.repocommand gitano.copycommand gitano.auth
 
 SKEL_FILES := gitano-admin/rules/selfchecks.lace			\
 	      gitano-admin/rules/aschecks.lace 				\
diff --git a/bin/gitano-command.cgi.in b/bin/gitano-command.cgi.in
new file mode 100755
index 0000000..bc280b2
--- /dev/null
+++ b/bin/gitano-command.cgi.in
@@ -0,0 +1,91 @@
+-- @@SHEBANG
+-- -*- Lua -*-
+-- command cgi
+--
+-- Git (with) Augmented network operations -- User authentication wrapper
+--
+-- Copyright 2014 Codethink Ltd
+--
+--
+
+-- @@GITANO_LUA_PATH
+
+local gitano = require "gitano"
+local gall = require "gall"
+local luxio = require "luxio"
+local sio = require "luxio.simple"
+
+-- @@GITANO_BIN_PATH
+-- @@GITANO_SHARE_PATH
+
+local stdout = sio.stdout
+
+function url_decode(str)
+  str = string.gsub (str, "+", " ")
+  str = string.gsub (str, "%%(%x%x)",
+      function(h) return string.char(tonumber(h,16)) end)
+  str = string.gsub (str, "\r\n", "\n")
+  return str
+end
+
+function run_command(cmd, cmdline, parsed_cmdline, user, config, env)
+   gitano.log.debug("Welcome to " .. config.global.site_name)
+   gitano.log.debug("Running:")
+   for i = 1, #parsed_cmdline do
+      gitano.log.debug(" => " .. parsed_cmdline[i])
+   end
+   gitano.log.debug("")
+   gitano.log.debug("On behalf of " .. user .. " using key " .. env["GITANO_KEYTAG"])
+
+   local how, why = cmd.run(config, repo, parsed_cmdline, env)
+
+   if how ~= "exit" or why ~= 0 then
+      gitano.log.critical("Error running " .. parsed_cmdline[1] .. ": " .. how)
+      return why
+   else
+      gitano.log.syslog.info(cmdline, "completed successfully")
+      return 0
+   end
+end
+
+if os.getenv("QUERY_STRING") then
+   local query_string = url_decode(os.getenv("QUERY_STRING"))
+   local cmdline = query_string
+
+   local _, e = string.find(query_string, "cmd=")
+
+   if not e then
+      stdout:write("Status: 400 Bad request\r\n\r\n")
+      stdout:write("Malformed command line, format: ?cmd=arg0 arg1 ... argn\n")
+      return
+   end
+
+   cmdline = string.sub(query_string, e + 1, #query_string)
+
+   if cmdline == '' then
+      stdout:write("Status: 400 Bad request\r\n\r\n")
+      stdout:write("Malformed command line, format: ?cmd=arg0 arg1 ... argn\n")
+      return
+   end
+
+   local user = os.getenv("REMOTE_USER") or "gitano/anonymous"
+
+   gitano.log.buffer_output()
+
+   local authorized, cmd, parsed_cmdline, config, env =
+      gitano.auth.is_authorized(user, "http", cmdline)
+
+   if authorized then
+      local exit = run_command(cmd, cmdline, parsed_cmdline, user, config, env)
+
+      stdout:write("Status: " .. (exit == 0 and "200 OK" or "400 Bad request")
+         .. "\r\n\r\n")
+      stdout:write(gitano.log.get_buffered_output() or "")
+   else
+      stdout:write("Status: 403 Forbidden\r\n\r\n")
+      stdout:write(gitano.log.get_buffered_output() or "")
+   end
+else
+   stdout:write("Status: 400 Bad request\r\n\r\n")
+   stdout:write("Malformed command line, format: ?cmd=arg0 arg1 ... argn\n")
+end
diff --git a/bin/gitano-setup.in b/bin/gitano-setup.in
index fbfa58a..61a3246 100644
--- a/bin/gitano-setup.in
+++ b/bin/gitano-setup.in
@@ -161,6 +161,7 @@ validate_name(ask_for("admin.keyname", "Key name for administrator",
 
 ask_for("site.name", "Site name", "a random Gitano instance")
 ask_for("log.prefix", "Site log prefix", "gitano")
+ask_for("use.htpasswd", "Store passwords with htpasswd? (needed for http authentication)", "no")
 
 gitano.log.chat("Step 2: Gather required content")
 
@@ -169,6 +170,7 @@ local completely_flat = {}
 local site_conf = clod.parse("")
 site_conf.settings["site_name"] = get "site.name"
 site_conf.settings["log.prefix"] = get "log.prefix"
+site_conf.settings["use_htpasswd"] = get "use.htpasswd"
 completely_flat["site.conf"] = site_conf:serialise()
 
 -- Acquire the contents of the skeleton gitano-admin repository
diff --git a/bin/gitano-smart-http.cgi.in b/bin/gitano-smart-http.cgi.in
new file mode 100755
index 0000000..8fb0240
--- /dev/null
+++ b/bin/gitano-smart-http.cgi.in
@@ -0,0 +1,76 @@
+-- @@SHEBANG
+-- -*- Lua -*-
+-- gitano-smart-http
+--
+-- Git (with) Augmented network operations -- User authentication wrapper
+--
+-- Copyright 2014 Codethink Ltd
+--
+--
+
+-- @@GITANO_LUA_PATH
+
+local gitano = require "gitano"
+local gall = require "gall"
+local luxio = require "luxio"
+local subprocess = require "luxio.subprocess"
+local sio = require "luxio.simple"
+
+-- @@GITANO_BIN_PATH
+-- @@GITANO_SHARE_PATH
+
+local stdout = sio.stdout
+
+function parse_get_request()
+   query_string = os.getenv("QUERY_STRING")
+
+   if query_string then
+      command = string.gsub(query_string, "^service=", "")
+      repo = string.match(os.getenv("PATH_INFO"), '/(.+)/info/refs')
+      return command .. " '" .. repo .. "'"
+   end
+
+   return nil
+end
+
+function parse_post_request()
+   path_info = os.getenv("PATH_INFO")
+
+   if path_info then
+      repo, command = string.match(path_info, "/(.+)/(.+)")
+      return command .. " '" .. repo .. "'"
+   end
+
+   return nil
+end
+
+function parse_request(request_method)
+   if request_method == "GET" then
+      return parse_get_request()
+   elseif request_method == "POST" then
+      return parse_post_request()
+   end
+end
+
+request_method = os.getenv("REQUEST_METHOD")
+
+if request_method == "GET" or request_method == "POST" then
+   local user = os.getenv("REMOTE_USER") or "gitano/anonymous"
+   local cmdline = parse_request(request_method)
+
+   if cmdline and gitano.auth.is_authorized(user, "http", cmdline) then
+      local proc = subprocess.spawn_simple({"git", "http-backend"})
+      local exit_code
+
+      _, exit_code = proc:wait()
+
+      if exit_code ~= 0 then
+         stdout:write("Status: 500 Internal Server Error\r\n\r\n")
+      end
+   else
+      stdout:write("Status: 403 Forbidden\r\n\r\n")
+   end
+else
+   stdout:write("Status: 405 Method Not Allowed\r\n")
+   stdout:write("Allow: GET, POST\r\n\r\n")
+end
diff --git a/lib/gitano.lua b/lib/gitano.lua
index ad3cd7c..b57bd71 100644
--- a/lib/gitano.lua
+++ b/lib/gitano.lua
@@ -14,6 +14,7 @@ local actions = require 'gitano.actions'
 local lace = require 'gitano.lace'
 local markdown = require 'gitano.markdown'
 local supple = require 'gitano.supple'
+local auth = require 'gitano.auth'
 
 return {
    util = util,
@@ -25,4 +26,5 @@ return {
    lace = lace,
    markdown = markdown,
    supple = supple,
+   auth = auth
 }
diff --git a/lib/gitano/auth.lua b/lib/gitano/auth.lua
new file mode 100644
index 0000000..8cdd8ec
--- /dev/null
+++ b/lib/gitano/auth.lua
@@ -0,0 +1,140 @@
+local config = require 'gitano.config'
+local command = require 'gitano.command'
+local log = require 'gitano.log'
+local repository = require 'gitano.repository'
+local util = require 'gitano.util'
+local gall = require 'gall'
+
+local function load_admin_conf(repo_root)
+   local admin_repo = gall.repository.new((repo_root or "") ..
+      "/gitano-admin.git")
+
+   if not admin_repo then
+      log.critical("Unable to locate administration repository.")
+      return nil
+   end
+
+   local admin_head = admin_repo:get(admin_repo.HEAD)
+
+   if not admin_head then
+      log.critical("Unable to find the HEAD of the administration repository.")
+      return nil
+   end
+
+   local admin_conf, msg = config.parse(admin_head)
+
+   if not admin_conf then
+      log.critical("Unable to parse administration repository.")
+      log.critical("  * " .. (msg or "No error?"))
+      return nil
+   end
+
+   return admin_conf
+end
+
+local function set_environment(repo_root, repo, context, transactionid)
+   local env = {
+      ["GITANO_ROOT"] = repo_root,
+      ["GITANO_USER"] = context.user,
+      ["GITANO_KEYTAG"] = context.keytag,
+      ["GITANO_PROJECT"] = (repo or {}).name or "",
+      ["GITANO_SOURCE"] = context.source,
+      ["GITANO_TRANSACTION_ID"] = transactionid,
+   }
+
+   for k, v in pairs(env) do
+      luxio.setenv(k, v)
+   end
+
+   return env
+end
+
+local function is_authorized(user, source, cmdline)
+   local repo_root = os.getenv("GITANO_ROOT")
+   local keytag = ""
+   local authorized = false
+
+   local start_log_level = log.get_level()
+   log.cap_level(log.level.INFO)
+   local transactionid = log.syslog.open()
+
+   config.repo_path(repo_root)
+
+   if not user or not cmdline then
+      return nil
+   end
+
+   local parsed_cmdline, warnings = util.parse_cmdline(cmdline)
+
+   if (#warnings > 0) then
+      log.error("Error parsing command");
+      return nil
+   end
+
+   local admin_conf = load_admin_conf(repo_root)
+   if admin_conf == nil then
+      log.fatal("Couldn't load a config from the admin repository")
+   end
+
+   if admin_conf.groups["gitano-admin"].filtered_members[user] then
+      log.set_level(start_log_level)
+   end
+
+   if not admin_conf.global.silent then
+      log.bump_level(log.level.CHAT)
+   end
+
+   ip = os.getenv("REMOTE_ADDR") or "unknown ip"
+   log.syslog.info("Client connected from", ip, "as", user,
+      "(" .. keytag .. ")", "Executing command:", cmdline)
+
+   local cmd = command.get(parsed_cmdline[1])
+
+   if not cmd then
+      log.critical("Unknown command: " .. parsed_cmdline[1])
+      return nil
+   end
+
+   local repo
+   if cmd.takes_repo and #parsed_cmdline > 1 then
+      -- Acquire the repository object for the target repo
+      local msg
+      repo, msg = repository.find(admin_conf, parsed_cmdline[2])
+
+      if not repo then
+         log.critical("Unable to locate repository.")
+         log.critical("  * " .. (tostring(msg) or "No error"))
+         return nil
+      end
+   end
+
+   if not cmd.validate(admin_conf, repo, parsed_cmdline) then
+      log.critical("Validation of command line failed")
+      return nil
+   end
+
+   local context = {source = source, user = user, keytag = keytag}
+   local action, reason = cmd.prep(admin_conf, repo, parsed_cmdline, context)
+
+   if not action then
+      log.critical(reason)
+      log.critical("Ruleset did not complete cleanly")
+      return nil
+   end
+
+   local env
+   if action == "allow" then
+      log.info(reason or "Ruleset permitted action")
+      authorized = true
+      env = set_environment(repo_root, repo, context, transactionid)
+   else
+      log.critical(reason)
+      log.critical("Ruleset denied action.  Sorry.")
+   end
+
+   return authorized, cmd, parsed_cmdline, admin_conf, env
+end
+
+return {
+   is_authorized = is_authorized
+}
diff --git a/lib/gitano/config.lua b/lib/gitano/config.lua
index 865e222..afa9072 100644
--- a/lib/gitano/config.lua
+++ b/lib/gitano/config.lua
@@ -82,32 +82,31 @@ local function parse_admin_config(commit)
    for filename, obj in pairs(flat_tree) do
       local prefix, username = filename:match("^(users/.-)([a-z][a-z0-9_-]+)/user%.conf$")
       if prefix and username then
-	 if not is_blob(obj) then
-	    return nil, prefix .. username .. "/user.conf is not a blob?"
-	 end
-	 if users[username] then
-	    return nil, "Duplicate user name: " .. username
-	 end
-	 -- Found a user, fill them out
-	 local user_clod, err =
-	    clod.parse(obj.obj.content,
-			 commit.sha .. ":" .. prefix .. username .. "/user.conf")
-
-	 if not user_clod then
-	    return nil, err
-	 end
-
-	 if type(user_clod.settings.real_name) ~= "string" then
-	    return nil, "gitano-admin:" .. commit.sha .. ":" .. prefix .. username .. "/user.conf missing real_name"
-	 end
-	 if (user_clod.settings.email_address and
-	     type(user_clod.settings.email_address) ~= "string") then
-	    return nil, "gitano-admin:" .. commit.sha .. ":" .. prefix .. username .. "/user.conf email_address is bad"
-	 end
-	 users[username] = setmetatable({ clod = user_clod,
-					  keys = {},
-					  meta = { prefix = prefix },
-					}, user_mt)
+         if not is_blob(obj) then
+            return nil, prefix .. username .. "/user.conf is not a blob?"
+         end
+         if users[username] then
+            return nil, "Duplicate user name: " .. username
+         end
+
+         -- Found a user, fill them out
+         local user_clod, err = clod.parse(obj.obj.content,
+            commit.sha .. ":" .. prefix .. username .. "/user.conf")
+
+         if not user_clod then
+            return nil, err
+         end
+
+         if type(user_clod.settings.real_name) ~= "string" then
+            return nil, "gitano-admin:" .. commit.sha .. ":" .. prefix .. username .. "/user.conf missing real_name"
+         end
+         if (user_clod.settings.email_address and
+             type(user_clod.settings.email_address) ~= "string") then
+            return nil, "gitano-admin:" .. commit.sha .. ":" .. prefix .. username .. "/user.conf email_address is bad"
+         end
+
+         users[username] = setmetatable({ clod = user_clod, keys = {},
+            meta = { prefix = prefix }, }, user_mt)
       end
    end
 
@@ -116,41 +115,41 @@ local function parse_admin_config(commit)
    for filename, obj in pairs(flat_tree) do
       local prefix, username, keyname = filename:match("^(users/.-)([a-z][a-z0-9_-]+)/([a-z][a-z0-9_-]+)%.key$")
       if prefix and username and keyname then
-	 if not users[username] then
-	    return nil, "Found a key (" .. keyname .. ") for " .. username .. " which lacks a user.conf"
-	 end
-	 local this_key = obj.obj.content
-
-	 this_key = this_key:gsub("\n*$", "")
-
-	 if this_key:match("\n") then
-	    return nil, "Key " .. filename .. " has newlines in it -- is it in the wrong format?"
-	 end
-
-	 local keytype, keydata, keytag = this_key:match("^([^ ]+) ([^ ]+) ([^ ].*)$")
-	 if not (keytype and keydata and keytag) then
-	    return nil, "Unable to parse key, " .. filename .. " did not smell like an OpenSSH v2 key"
-	 end
-	 if (keytype ~= "ssh-rsa") and (keytype ~= "ssh-dss") and
-	    (keytype ~= "ecdsa-sha2-nistp256") and 
-	    (keytype ~= "ecdsa-sha2-nistp384") and
-	    (keytype ~= "ecdsa-sha2-nistp521") then
-	    return nil, "Unknown key type " .. keytype .. " in " .. filename
-	 end
-
-	 if all_keys[this_key] then
-	    return nil, ("Duplicate key found at (" .. keyname .. 
-			 ") for " .. username .. ".  Previously found as (" ..
-			    all_keys[this_key].keyname .. ") for " ..
-			    all_keys[this_key].username)
-	 end
-	 all_keys[this_key] = { keyname = keyname, username = username }
-	 users[username].keys[keyname] = { 
-	    data = this_key, 
-	    keyname = keyname, 
-	    username = username, 
-	    keytag = keytag,
-	 }
+         if not users[username] then
+            return nil, "Found a key (" .. keyname .. ") for " .. username .. " which lacks a user.conf"
+         end
+         local this_key = obj.obj.content
+
+         this_key = this_key:gsub("\n*$", "")
+
+         if this_key:match("\n") then
+            return nil, "Key " .. filename .. " has newlines in it -- is it in the wrong format?"
+         end
+
+         local keytype, keydata, keytag = this_key:match("^([^ ]+) ([^ ]+) ([^ ].*)$")
+         if not (keytype and keydata and keytag) then
+            return nil, "Unable to parse key, " .. filename .. " did not smell like an OpenSSH v2 key"
+         end
+         if (keytype ~= "ssh-rsa") and (keytype ~= "ssh-dss") and
+            (keytype ~= "ecdsa-sha2-nistp256") and
+            (keytype ~= "ecdsa-sha2-nistp384") and
+            (keytype ~= "ecdsa-sha2-nistp521") then
+            return nil, "Unknown key type " .. keytype .. " in " .. filename
+         end
+
+         if all_keys[this_key] then
+            return nil, ("Duplicate key found at (" .. keyname .. ") for " ..
+               username .. ".  Previously found as (" ..
+               all_keys[this_key].keyname .. ") for " ..
+               all_keys[this_key].username)
+         end
+         all_keys[this_key] = { keyname = keyname, username = username }
+         users[username].keys[keyname] = {
+            data = this_key,
+            keyname = keyname,
+            username = username,
+            keytag = keytag,
+         }
       end
    end
 
@@ -369,30 +368,32 @@ local function commit_config_changes(conf, desc, username)
    -- write out everything we have here, and then prepare
    -- and write out a commit.
    local newtree = {}
+
    -- Shallow copy the tree ready for mods, skipping users and groups
    for k,v in pairs(conf.content) do
       if not (k:match("^users/") or
-	      k:match("^groups/")) then
-	 newtree[k] = v
+         k:match("^groups/")) then
+         newtree[k] = v
       end
    end
+
    -- Write out the site.conf
-   local obj = conf.repo.git:hash_object("blob",
-					 conf.clod:serialise(),
-					 true)
+   local obj = conf.repo.git:hash_object("blob", conf.clod:serialise(), true)
    newtree["site.conf"] = conf.repo.git:get(obj)
+
    -- Construct all the users and write them out.
    for u, utab in pairs(conf.users) do
       local str = utab.clod:serialise()
       local obj = conf.repo.git:hash_object("blob", str, true)
       newtree[utab.meta.prefix .. u .. "/user.conf"] = conf.repo.git:get(obj)
+
       -- Now the keys
       for k, ktab in pairs(utab.keys) do
-	 obj = conf.repo.git:hash_object("blob", ktab.data .. "\n", true)
-	 newtree[utab.meta.prefix .. u .. "/" .. k .. ".key"] = 
-	    conf.repo.git:get(obj)
+         obj = conf.repo.git:hash_object("blob", ktab.data .. "\n", true)
+         newtree[utab.meta.prefix .. u .. "/" .. k .. ".key"] = conf.repo.git:get(obj)
       end
    end
+
    -- Do the same for the groups
    for g, gtab in pairs(conf.groups) do
       obj = conf.repo.git:hash_object("blob", gtab.clod:serialise(), true)
diff --git a/lib/gitano/log.lua b/lib/gitano/log.lua
index f243b87..e1df00b 100644
--- a/lib/gitano/log.lua
+++ b/lib/gitano/log.lua
@@ -14,6 +14,7 @@ local prefix = "[gitano] "
 local transactionid = nil
 
 local stream = sio.stderr
+local is_buffered = false
 
 local ERRS = 0
 local WARN = 1
@@ -24,6 +25,40 @@ local DEEPDEBUG = 5
 
 local level = ERRS
 
+local LogBuf = {}
+LogBuf.__index = LogBuf
+
+function LogBuf:new()
+   return setmetatable({strings = {}}, self)
+end
+
+function LogBuf:write(s)
+   table.insert(self.strings, s)
+end
+
+function LogBuf:get()
+   return table.concat(self.strings)
+end
+
+local function is_buffered_output()
+   return is_buffered
+end
+
+local function buffer_output()
+   if not is_buffered_output() then
+      stream = LogBuf:new()
+      is_buffered = true
+   end
+end
+
+local function get_buffered_output()
+   if is_buffered_output() then
+      return stream:get()
+   else
+      return nil
+   end
+end
+
 local function syslog_write(priority, ...)
    local strs = {...}
 
@@ -98,15 +133,26 @@ end
 
 local function stdout(...)
    local savedstream, savedprefix = stream, prefix
-   stream, prefix = sio.stdout, ""
+
+   prefix = ""
+   if not is_buffered_output() then
+      stream = sio.stdout
+   end
+
    state(...)
    stream, prefix = savedstream, savedprefix
 end
 
 local function fatal(...)
-   syslog_write(luxio.LOG_EMERG, ...)
+   syslog_write(luxio.LOG_CRIT, ...)
    AT(ERRS, "FATAL:", ...)
-   stream:close()
+
+   if is_buffered_output() then
+      sio.stderr:write(get_buffered_output())
+   else
+      stream:close()
+   end
+
    luxio._exit(1)
 end
 
@@ -244,5 +290,8 @@ return {
       info = syslog_info,
       debug = syslog_debug,
       close = syslog_close,
-   }
+   },
+   buffer_output = buffer_output,
+   is_buffered_output = is_buffered_output,
+   get_buffered_output = get_buffered_output
 }
diff --git a/lib/gitano/repository.lua b/lib/gitano/repository.lua
index 5d4a194..a15fcbe 100644
--- a/lib/gitano/repository.lua
+++ b/lib/gitano/repository.lua
@@ -183,8 +183,13 @@ function repo_method:check_local_git_files()
    end
    if anonexport then
       log.ddebug("<" .. self.name .. ">: Anonymous read allowed")
-      local fh = sio.open(self:fs_path() .. "/git-daemon-export-ok", "wc")
-      fh:close()
+      local fh, errmsg = sio.open(self:fs_path() .. "/git-daemon-export-ok", "wc")
+
+      if fh then
+        fh:close()
+      else
+        log.warn("Can't create git-daemon-export file:", errmsg)
+      end
    else
       log.ddebug("<" .. self.name .. ">: Anonymous read not allowed")
       luxio.unlink(self:fs_path() .. "/git-daemon-export-ok")
diff --git a/lib/gitano/usercommand.lua b/lib/gitano/usercommand.lua
index d28b203..3c8b467 100644
--- a/lib/gitano/usercommand.lua
+++ b/lib/gitano/usercommand.lua
@@ -10,6 +10,7 @@ local repository = require 'gitano.repository'
 local config = require 'gitano.config'
 
 local sio = require 'luxio.simple'
+local subprocess = require 'luxio.subprocess'
 
 local builtin_whoami_short = "Find out how Gitano identifies you"
 
@@ -20,15 +21,19 @@ Tells you who you are, what your email address is set to, what keys you have
 registered etc.
 ]]
 
-local function builtin_whoami_validate(config, repo, cmdline)
-   -- whoami
+local function validate_single_argcmd(cmdline, msg)
    if #cmdline > 1 then
-      log.error("usage: whoami")
+      log.error(msg)
       return false
    end
+
    return true
 end
 
+local function builtin_whoami_validate(_, _, cmdline)
+   return validate_single_argcmd(cmdline, "usage: whoami")
+end
+
 local function builtin_whoami_prep(config, repo, cmdline, context)
    context.operation = "whoami"
    return config.repo:run_lace(context)
@@ -37,6 +42,11 @@ end
 local function builtin_whoami_run(config, repo, cmdline, env)
    local username = env["GITANO_USER"]
    local userdata = config.users[username]
+
+   if not userdata then
+      return "I don't know who you are", 1
+   end
+
    log.stdout("    User name:", username)
    log.stdout("    Real name:", userdata.real_name or "Unknown")
    log.stdout("Email address:", userdata.email_address or "unknown@example.com")
@@ -159,53 +169,158 @@ local function builtin_sshkey_run(conf, _, cmdline, env)
    local utab = conf.users[env.GITANO_USER]
    if cmdline[2] == "list" then
       if not next(utab.keys) then
-	 log.warn("There are no SSH keys registered for", env.GITANO_USER .. ", sorry")
+         log.warn("There are no SSH keys registered for", env.GITANO_USER
+            .. ", sorry")
       else
-	 local pfx = "      SSH key:"
-	 for tagname, keydata in pairs(utab.keys) do
-	    local suffix = (env.GITANO_KEYTAG == tagname) and " [*]" or ""
-	    log.state(pfx, tagname, "=>", keydata.keytag .. suffix)
-	    pfx = "              "
-	 end
+         local pfx = "      SSH key:"
+         for tagname, keydata in pairs(utab.keys) do
+            local suffix = (env.GITANO_KEYTAG == tagname) and " [*]" or ""
+            log.state(pfx, tagname, "=>", keydata.keytag .. suffix)
+            pfx = "              "
+         end
       end
    elseif cmdline[2] == "add" then
       local sshkey = sio.stdin:read("*l")
       local keytype, keydata, keytag = sshkey:match("^([^ ]+) ([^ ]+) ([^ ].*)$")
       if not (keytype and keydata and keytag) then
-	 log.error("Unable to parse key,", filename,
-		   "did not smell like an OpenSSH v2 key")
-	 return "exit", 1
+         log.error("Unable to parse key,", filename,
+            "did not smell like an OpenSSH v2 key")
+         return "exit", 1
       end
+
       if (keytype ~= "ssh-rsa") and (keytype ~= "ssh-dss") and
-	 (keytype ~= "ecdsa-sha2-nistp256") and 
-	 (keytype ~= "ecdsa-sha2-nistp384") and
-	 (keytype ~= "ecdsa-sha2-nistp521") then
-	 log.error("Unknown key type", keytype)
-	 return "exit", 1
+         (keytype ~= "ecdsa-sha2-nistp256") and
+         (keytype ~= "ecdsa-sha2-nistp384") and
+         (keytype ~= "ecdsa-sha2-nistp521") then
+         log.error("Unknown key type", keytype)
+         return "exit", 1
       end
+
       local keytab = {
-	 data = sshkey,
-	 keyname = cmdline[3],
-	 username = env.GITANO_USER,
-	 keytag = keytag,
+         data = sshkey,
+         keyname = cmdline[3],
+         username = env.GITANO_USER,
+         keytag = keytag,
       }
+
       utab.keys[cmdline[3]] = keytab
-      
    elseif cmdline[2] == "del" then
       utab.keys[cmdline[3]] = nil
    end
 
    if cmdline[2] ~= "list" then
       -- Store the config back.
+
       local action = (cmdline[2] == "add") and "Added" or "Deleted"
       action = action .. " " .. cmdline[3] .. " for " .. env.GITANO_USER
       local ok, msg = config.commit(conf, action, env.GITANO_USER)
+
+      if not ok then
+         log.error(msg)
+         return "exit", 1
+      end
+   end
+
+   return "exit", 0
+end
+
+local builtin_passwd_short = "Set your password"
+
+local builtin_passwd_helptext = [[
+usage: passwd
+
+Sets your password, the password is read from stdin.
+
+If no password is provided your password is removed (if you have one).
+]]
+
+local function builtin_passwd_validate(_, _, cmdline)
+   return validate_single_argcmd(cmdline, "usage: passwd")
+end
+
+local function builtin_passwd_prep(conf, repo, cmdline, context)
+   context.operation = "passwd"
+
+   local action, reason = conf.repo:run_lace(context)
+   if action == "deny" then
+      return reason
+   end
+
+   return action, reason
+end
+
+local function update_htpasswd(user, passwd)
+   local htpasswd_path = os.getenv("HOME") .. "/htpasswd"
+   local flags = io.open(htpasswd_path, "r") and "" or "-c"
+   local exit_code
+
+   if passwd ~= '' then
+      local proc = subprocess.spawn_simple({
+         "htpasswd", flags, htpasswd_path, user,
+         stdin = passwd .. '\n' .. passwd .. '\n',
+         stdout = subprocess.PIPE,
+         stderr = subprocess.PIPE
+      })
+
+      _, exit_code = proc:wait()
+   else
+      local proc = subprocess.spawn_simple({
+         "htpasswd", "-D", htpasswd_path, user,
+         stdout = subprocess.PIPE,
+         stderr = subprocess.PIPE
+      })
+
+      _, exit_code = proc:wait()
+   end
+
+   return exit_code == 0
+end
+
+local function builtin_passwd_run(conf, _, cmdline, env)
+   local user = env.GITANO_USER
+
+   local password = sio.stdin:read("*l")
+   local method, hash = util.hash_password(password)
+
+   if conf.users[user].hash == nil and password == "" then
+      log.chat(string.format("Password for %s is not set and no password was"
+         .. " provided, no action taken.", user))
+      return "exit", 0
+   end
+
+   if password ~= "" then
+      conf.users[user].method = method
+      conf.users[user].hash = hash
+   else
+      -- user's password will be removed
+      conf.users[user].method = nil
+      conf.users[user].hash = nil
+   end
+
+   local ok, msg
+
+   if conf.clod.settings["use_htpasswd"] == "yes" then
+      ok = update_htpasswd(user, password)
+
       if not ok then
-	 log.error(msg)
-	 return "exit", 1
+         log.error("Failed to update htpasswd file")
+         return "exit", 1
       end
    end
 
+   local action = string.format("%s password for %s",
+      password ~= '' and "Update" or "Remove", user)
+
+   ok, msg = config.commit(conf, action, user)
+
+   if not ok then
+      log.error(msg)
+      return "exit", 1
+   end
+
+   log.chat(string.format("%s password for %s",
+      password ~= '' and "Updated" or "Removed", user))
+
    return "exit", 0
 end
 
@@ -216,6 +331,9 @@ local function register_commands(reg)
    assert(reg("sshkey", builtin_sshkey_short, builtin_sshkey_helptext,
 	      builtin_sshkey_validate, builtin_sshkey_prep,
 	      builtin_sshkey_run, false, false))
+   assert(reg("passwd", builtin_passwd_short, builtin_passwd_helptext,
+         builtin_passwd_validate, builtin_passwd_prep,
+         builtin_passwd_run, false, false))
 end
 
 return {
diff --git a/lib/gitano/util.lua b/lib/gitano/util.lua
index 51c5bc2..c2a53a7 100644
--- a/lib/gitano/util.lua
+++ b/lib/gitano/util.lua
@@ -9,9 +9,20 @@
 local luxio = require 'luxio'
 local sio = require 'luxio.simple'
 local log = require 'gitano.log'
+local scrypt = require 'scrypt'
 
 local tconcat = table.concat
 
+local check_password = scrypt.verify_password
+
+local function hash_password(password)
+   -- For the moment we are using scrypt,
+   -- we may decide to use other hash functions in the future
+   -- so it's useful to provide some way to identify which hash
+   -- function was used
+   return 'scrypt', scrypt.hash_password(password, 2^14, 8, 1)
+end
+
 local function _deep_copy(t, memo)
    if not memo then memo = {} end
    if memo[t] then return memo[t] end
@@ -480,4 +491,7 @@ return {
    process_expansion = process_expansion,
 
    set = set,
+
+   hash_password = hash_password,
+   check_password = check_password,
 }
diff --git a/scripts/htpasswd b/scripts/htpasswd
new file mode 100755
index 0000000..a28ba2a
--- /dev/null
+++ b/scripts/htpasswd
@@ -0,0 +1,151 @@
+#!/usr/bin/env python
+# Based on FreeBSD src/lib/libcrypt/crypt.c 1.2
+# http://www.freebsd.org/cgi/cvsweb.cgi/~checkout~/src/lib/libcrypt/crypt.c?rev=1.2&content-type=text/plain
+#
+# Original license:
+# * "THE BEER-WARE LICENSE" (Revision 42):
+# * <phk@login.dknet.dk> wrote this file.  As long as you retain this notice you
+# * can do whatever you want with this stuff. If we meet some day, and you think
+# * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
+#
+# This port adds no further stipulations.  I forfeit any copyright interest.
+
+from __future__ import print_function
+import md5
+import random
+import string
+import sys
+import getpass
+
+def hash(password, salt, magic='$apr1$'):
+    # /* The password first, since that is what is most unknown */ /* Then our magic string */ /* Then the raw salt */
+    m = md5.new()
+    m.update(password + magic + salt)
+
+    # /* Then just as many characters of the MD5(pw,salt,pw) */
+    mixin = md5.md5(password + salt + password).digest()
+    for i in range(0, len(password)):
+        m.update(mixin[i % 16])
+
+    # /* Then something really weird... */
+    # Also really broken, as far as I can tell.  -m
+    i = len(password)
+    while i:
+        if i & 1:
+            m.update('\x00')
+        else:
+            m.update(password[0])
+        i >>= 1
+
+    final = m.digest()
+
+    # /* and now, just to make sure things don't run too fast */
+    for i in range(1000):
+        m2 = md5.md5()
+        if i & 1:
+            m2.update(password)
+        else:
+            m2.update(final)
+
+        if i % 3:
+            m2.update(salt)
+
+        if i % 7:
+            m2.update(password)
+
+        if i & 1:
+            m2.update(final)
+        else:
+            m2.update(password)
+
+        final = m2.digest()
+
+    # This is the bit that uses to64() in the original code.
+
+    itoa64 = './0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz'
+
+    rearranged = ''
+    for a, b, c in ((0, 6, 12), (1, 7, 13), (2, 8, 14), (3, 9, 15), (4, 10, 5)):
+        v = ord(final[a]) << 16 | ord(final[b]) << 8 | ord(final[c])
+        for i in range(4):
+            rearranged += itoa64[v & 0x3f]; v >>= 6
+
+    v = ord(final[11])
+    for i in range(2):
+        rearranged += itoa64[v & 0x3f]; v >>= 6
+
+    return magic + salt + '$' + rearranged
+
+def usage():
+    print('%s: usage: %s [-cD] passwdfile username' %
+        (sys.argv[0], sys.argv[0]), file=sys.stderr)
+
+def salt(len):
+    return ''.join([random.choice(string.ascii_letters + string.digits)
+        for x in range(len)])
+
+def write_passwords(passwords, path):
+    with open(path, 'w') as f:
+        for (username, pwhash) in passwords:
+            f.write('%s:%s\n' % (username, pwhash))
+
+def ask_password():
+    x = getpass.getpass('New password: ')
+    y = getpass.getpass('Re-type password: ')
+
+    return x if x == y else None
+
+if len(sys.argv) not in [3, 4]:
+    if len(sys.argv) == 4 and sys.argv[1] not in ['-c', '-D', '-cD', '-Dc']:
+        usage()
+        sys.exit(2)
+
+flags = len(sys.argv) == 4
+create_flag = flags and 'c' in sys.argv[1]
+delete_flag = flags and 'D' in sys.argv[1]
+
+if create_flag and delete_flag:
+    print('%s: -c and -D options conflict' % sys.argv[0], file=sys.stderr)
+    sys.exit(2)
+
+file_path = sys.argv[flags + 1]
+username = sys.argv[flags + 2]
+
+if not delete_flag:
+    password = ask_password()
+
+    if password == None:
+        exit("%s: passwords weren't the same" % sys.argv[0])
+
+contents = []
+found = False
+
+if not create_flag:
+    with open(file_path, 'r') as f:
+        # read in the existing passwd file
+        # replace entry for 'username' with entry containing new hash
+        # unless -D is used, in which case we remove the entry
+        #
+        # example entry: username:$apr1$gdehCd2T$ppFjRXlf1alPKSHqcBrjk0
+
+        for line in f:
+            (u, ph) = string.split(line.strip('\n'), ':')
+
+            if u == username:
+                if not delete_flag:
+                    ph = hash(password, salt(8))
+                    print('Updating password for user %s' % username)
+                    contents.append((u, ph))
+
+                found = True
+            else:
+                contents.append((u, ph))
+
+if not found:
+    if delete_flag:
+        print('User %s not found' % username)
+    else:
+        print('Adding password for user %s' % username)
+        contents.append((username, hash(password, salt(8))))
+
+write_passwords(contents, file_path)
diff --git a/skel/gitano-admin/rules/defines.lace b/skel/gitano-admin/rules/defines.lace
index e72f598..95e729e 100644
--- a/skel/gitano-admin/rules/defines.lace
+++ b/skel/gitano-admin/rules/defines.lace
@@ -9,7 +9,8 @@ define if_asanother as_user ~.
 # Self-related operations
 define op_whoami operation whoami
 define op_sshkey operation sshkey
-define op_self anyof op_whoami op_sshkey
+define op_passwd operation passwd
+define op_self anyof op_whoami op_sshkey op_passwd
 
 # Admin-related operations
 
diff --git a/skel/gitano-admin/rules/selfchecks.lace b/skel/gitano-admin/rules/selfchecks.lace
index 300bb91..e30e557 100644
--- a/skel/gitano-admin/rules/selfchecks.lace
+++ b/skel/gitano-admin/rules/selfchecks.lace
@@ -3,3 +3,5 @@
 allow "You may ask who you are" op_whoami
 
 allow "You may manage your own ssh keys" op_sshkey
+
+allow "You may change your own password" op_passwd