CodeChecker authentication subsystem

CodeChecker also supports only allowing a privileged set of users to access the results stored on a server.

NOTICE! Some authentication subsystems require additional packages to be installed before they can be used. See below.

Table of Contents

Server-side configuration

The server's configuration is stored in the server's workspace folder, in server_config.json. This file is created, at the first start of the server, using the package's installed config/server_config.json as a template.

The authentication section of the config file controls how authentication is handled.

Every authentication method is its own JSON object in this section. Every authentication method has its own enabled key which dictates whether it is used at live authentication or not.

Users are authenticated if any authentication method successfully authenticates them. Authentications are attempted in the order they are described here: dicitonary takes precedence, pam is a secondary and ldap is a tertiary backend, if enabled.

Only refresh_time, session_lifetime and logins_until_cleanup options can be changed and reloaded without server restart by using the --reload option of CodeChecker server command.

Dictionary authentication

The authentication.method_dictionary contains a plaintext username:password credentials for authentication. If the user's login matches any of the credentials listed, the user will be authenticated.

Groups are configured in a map which maps to each username the list of groups the user belongs to.

"method_dictionary": {
  "enabled" : true,
  "auths" : [
      "global:admin",
      "test:test"
  ],
  "groups" : {
      "global" : ["admin", "guest"],
      "test" : ["guest"]
  }
}

External authentication methods

External authentication methods connect to a privilege manager to authenticate users against.

Using external authentication methods - such as PAM or LDAP - require additional packages and libraries to be installed on the system.

# get additional system libraries
sudo apt-get install libldap2-dev libsasl2-dev libssl-dev

# the python virtual environment must be sourced!
source ~/checker_env/bin/activate

# install required python modules
pip install -r requirements_py/auth/requirements.txt

PAM authentication

To access the server via PAM authentication, the user must provide valid username and password which is accepted by PAM.

"method_pam": {
  "enabled" : true
}

The module can be configured to allow specific users or users belonging to specific groups only. In the example below, root and myname can access the server, and everyone who belongs to the adm or cc-users group can access the server.

"method_pam": {
  "enabled" : true,
  "users": [
    "root", "myname"
  ],
  "groups": [
    "adm", "cc-users"
  ]
}

LDAP authentication

CodeChecker also supports LDAP-based authentication. The authentication.method_ldap section contains the configuration for LDAP authentication: the server can be configured to connect to as much LDAP-servers as the administrator wants. Each LDAP server is identified by a connection_url and a list of queries to attempt to log in the username given.

Servers are connected to and queries are executed in the order they appear in the configuration file. Because of this, it is not advised to list too many servers as it can elongate the authentication process.

Configuration options

URL of the LDAP server which will be queried for user information and group membership.

Optional username for LDAP bind, if not set bind with the login credentials will be attempted.

Optional password for configured username.

Microsoft Active Directory by returns referrals (search continuations). LDAPv3 does not specify which credentials should be used by the clients when chasing these referrals and will be tried as an anonymous access by the libldap library which might fail. Will be disabled by default.

Configure how the alias dereferencing is done in libldap (valid values: always, never).

Root tree containing all the user accounts.

Scope of the search performed. Accepted values are: base, one, subtree.

The special $USN$ token in the query is replaced to the username at login. Query pattern used to search for a user account. Must be a valid LDAP query expression.

Example configuration: (&(objectClass=person)(sAMAccountName=$USN$))

Root tree containing all the groups.

Group query pattern used LDAP query expression to find the group objects a user is a member of. It must contain a $USERDN$ pattern. $USERDN$ will be automatically replaced by the queried user account DN.

The attribute of the group object which contains the name of the group.

Scope of the search performed. (Valid values are: base, one, subtree)

"method_ldap": {
  "enabled" : true,
  "authorities": [
    {
      "connection_url": "ldap://ldap.example.org",
      "username" : null,
      "password" : null,
      "referrals" : false,
      "deref" : "always",
      "accountBase" : null,
      "accountScope" : "subtree",
      "accountPattern" : "(&(objectClass=person)(sAMAccountName=$USN$))",
      "groupBase" : null,
      "groupScope" : "subtree",
      "groupPattern" : "(&(objectClass=group)(member=$USERDN$))",
      "groupNameAttr" : "sAMAccountName"
    },
    {
      "connection_url" : "ldaps://secure.internal.example.org:636",
      "username" : null,
      "password" : null,
      "referrals" : false,
      "deref" : "always",
      "accountBase" : null,
      "accountScope" : "subtree",
      "accountPattern" : null,
      "groupBase" : null,
      "groupScope" : "subtree",
      "groupPattern" : null,
      "groupNameAttr" : null
    }
  ]
}

Client-side configuration

Web-browser client

Authentication in the web browser is handled via standard HTTP Authenticate headers, the browser will prompt the user to supply their credentials.

For browser authentication to work, cookies must be enabled!

Command-line client

The CodeChecker cmd client needs to be authenticated for a server before any data communication could take place.

The client's configuration file is expected to be at ~/.codechecker.passwords.json, which is created at the first command executed by using the package's config/session_client.json as an example.

Please make sure, as a security precaution, that only you are allowed to access this file. Executing chmod 0600 ~/.codechecker.passwords.json will limit access to your user only.

usage: CodeChecker cmd login [-h] [-d] [--url SERVER_URL]
                             [--verbose {info,debug,debug_analyzer}]
                             [USERNAME]

Certain CodeChecker servers can require elevated privileges to access analysis
results. In such cases it is mandatory to authenticate to the server. This
action is used to perform an authentication in the command-line.

positional arguments:
  USERNAME              The username to authenticate with. (default: <username>)

optional arguments:
  -h, --help            show this help message and exit
  -d, --deactivate, --logout
                        Send a logout request to end your privileged session.

common arguments:
  --url SERVER_URL      The URL of the server to access, in the format of
                        '[http[s]://]host:port'. (default: localhost:8001)
  --verbose {info,debug,debug_analyzer}
                        Set verbosity level.

The user can log in onto the server by issuing the command CodeChecker cmd login <username>. After receiving an Authentication successful! message, access to the analysis information is given; otherwise, Invalid access is shown instead of real data.

Privileged session expire after a set amount of time. To log out manually, issue the command CodeChecker cmd login -d.

Preconfigured credentials

To alleviate the need for supplying authentication in the command-line every time a server is connected to, users can pre-configure their credentials to be used in authentication.

To do so first copy the config/session_client.json file from the CodeChecker package to your home directory and rename it to .codechecker.passwords.json After creating the new file open ~/.codechecker.passwords.json.

The credentials section is used by the client to read pre-saved authentication data in username:password format.

{
  "client_autologin" : true,
  "credentials": {
    "*" : "global:passphrase",
    "*:8080" : "webserver:1234",
    "localhost" : "local:admin",
    "localhost:6251" : "super:secret"
  }
}

Credentials are matched for any particular server at login in the following order:

  1. An exact host:port match is tried
  2. Matching for the host (on any port) is tried
  3. Matching for a particular port (on any host address), in the form of *:port, is tried
  4. Global credentials for the installation is stored with the * key

Is it possible to generate a token from command line which can be used to authenticate in the name of the given user. This way no need to store passwords in text files. For more information see.

Automatic login

If authentication is required by the server and the user hasn't logged in but there are saved credentials for the server, CodeChecker cmd will automatically try to log in.

This behaviour can be disabled by setting client_autologin to false.

Currently active tokens

The user's currently active sessions' token are stored in the ~/.codechecker.session.json.

Personal access token

Command line clients can authenticate itself using the username/password stored in the .codechecker.passwords.json. It is obviously not a good idea to store passwords in text files. Instead of this the user is able to generate a token from command line, that can be used to authenticate in the name of his/her name. To generate a new token, the user must be logged in first.

Personal tokens can be written instead of the user's password in the ~/.codechecker.passwords.json file:

{
  "client_autologin" : true,
  "credentials": {
    "*" : "global:passphrase",
    "localhost:6251" : "super:22eca8f31ad117e90c371f2e98bcf4c9"
  }
}

New personal access token

usage: CodeChecker cmd token new [-h] [--description DESCRIPTION]
                                 [--url SERVER_URL]
                                 [--verbose {info,debug,debug_analyzer}]

Creating a new personal access token.

optional arguments:
  -h, --help            show this help message and exit
  --description DESCRIPTION
                        A custom textual description to be shown alongside the
                        token.

List personal access tokens

usage: CodeChecker cmd token list [-h] [--url SERVER_URL]
                                  [-o {plaintext,html,rows,table,csv,json}]
                                  [-e EXPORT_DIR] [-c]
                                  [--verbose {info,debug,debug_analyzer}]

List the available personal access tokens.

optional arguments:
  -h, --help            show this help message and exit

Remove personal access token

usage: CodeChecker cmd token del [-h] [--url SERVER_URL]
                                 [--verbose {info,debug,debug_analyzer}]
                                 TOKEN

Removes the specified access token.

positional arguments:
  TOKEN                 Personal access token which will be deleted.