Configurar NGINX Plus para el SSO mediante SAML con Microsoft Entra ID

# This is file frontend.conf 
# This is the backend application we are protecting with SAML SSO 
upstream my_backend { 
    zone my_backend 64k; 
    server dev.sports.com; 
} 

# Custom log format to include the 'NameID' subject in the REMOTE_USER field 
log_format saml_sso '$remote_addr - $saml_name_id [$time_local] "$request" "$host" ' 
                    '$status $body_bytes_sent "$http_referer" ' 
                    '"$http_user_agent" "$http_x_forwarded_for"'; 

# The frontend server - reverse proxy with SAML SSO authentication 
# 
server { 
    # Functional locations implementing SAML SSO support 
    include conf.d/saml_sp.server_conf; 
 

    # Reduce severity level as required 
    error_log /var/log/nginx/error.log debug; 
    listen 443 ssl; 
    ssl_certificate     /home/ubuntu/dev.sports.com.crt; 
    ssl_certificate_key  /home/ubuntu/dev.sports.com.key; 
    ssl_session_cache shared:SSL:5m; 
 

    location / { 
        # When a user is not authenticated (i.e., the "saml_access_granted." 
        # variable is not set to "1"), an HTTP 401 Unauthorized error is 
        # returned, which is handled by the @do_samlsp_flow named location. 
        error_page 401 = @do_samlsp_flow; 

        if ($saml_access_granted != "1") { 
            return 401; 
        } 

        # Successfully authenticated users are proxied to the backend, 
        # with the NameID attribute passed as an HTTP header        
        proxy_set_header mail $saml_attrib_mail;  # Microsoft Entra ID's user.mail 
        proxy_set_header objectid $saml_attrib_objectid; # Microsoft Entra ID's objectid 
        access_log /var/log/nginx/access.log saml_sso; 
        proxy_pass http://my_backend; 
        proxy_set_header Host dev.sports.com; 
        return 200 "Welcome to Application pagen My objectid is $http_objectidn My email is $http_mailn"; 
        default_type text/plain; 

   } 
} 
# vim: syntax=nginx         

keyval_zone    zone=saml_attrib_mail:1M                state=/var/lib/nginx/state/saml_attrib_email.json   timeout=1h; 
keyval   $cookie_auth_token $saml_attrib_mail    zone=saml_attrib_mail; 

 keyval_zone zone=saml_attrib_objectid:1M            state=/var/lib/nginx/state/saml_attrib_objectid.json   timeout=1h; 
keyval   $cookie_auth_token $saml_attrib_objectid   zone=saml_attrib_objectid; 

 # SAML SSO configuration 

map $host $saml_sp_entity_id { 
    # Unique identifier that identifies the SP to the IdP. 
    # Must be URL or URN. 
    default "https://dev.sports.com"; 
} 

map $host $saml_sp_acs_url { 
    # The ACS URL, an endpoint on the SP where the IdP  
    # will redirect to with its authentication response. 
    # Must match the ACS location defined in the "saml_sp.serer_conf" file. 
    default "https://dev.sports.com/saml/acs"; 
} 

map $host $saml_sp_request_binding { 
    # Refers to the method by which an authentication request is sent from 
    # the SP to an IdP during the Single Sign-On (SSO) process. 
    # Only HTTP-POST or HTTP-Redirect methods are allowed. 
    default 'HTTP-POST'; 
} 

map $host $saml_sp_sign_authn { 
    # Whether the SP should sign the AuthnRequest sent to the IdP. 
    default "false"; 
} 

map $host $saml_sp_decryption_key { 
    # Specifies the private key that the SP uses to decrypt encrypted assertion 
    # or NameID from the IdP. 
    default ""; 
} 

map $host $saml_sp_force_authn { 
    # Whether the SP should force re-authentication of the user by the IdP. 
    default "false"; 
} 

map $host $saml_sp_nameid_format { 
    # Indicates the desired format of the name identifier in the SAML assertion 
    # generated by the IdP. Check section 8.3 of the SAML 2.0 Core specification 
    # (http://docs.oasis-open.org/security/saml/v2.0/saml-core-2.0-os.pdf) 
    # for the list of allowed NameID Formats. 
    default "urn:oasis:names:tc:SAML:1.1:nameid-format:unspecified"; 
} 

map $host $saml_sp_relay_state { 
    # Relative or absolute URL the SP should redirect to 
    # after successful sign on. 
    default ""; 
} 

map $host $saml_sp_want_signed_response { 
    # Whether the SP wants the SAML Response from the IdP 
    # to be digitally signed. 
    default "false"; 
} 

map $host $saml_sp_want_signed_assertion { 
    # Whether the SP wants the SAML Assertion from the IdP 
    # to be digitally signed. 
    default "true"; 
} 

map $host $saml_sp_want_encrypted_assertion { 
    # Whether the SP wants the SAML Assertion from the IdP 
    # to be encrypted. 
    default "false"; 
} 

map $host $saml_idp_entity_id { 
    # Unique identifier that identifies the IdP to the SP. 
    # Must be URL or URN. 
    default "https://sts.windows.net/8807dced-9637-4205-a520-423077750c60/"; 
} 

map $host $saml_idp_sso_url { 
    # IdP endpoint that the SP will send the SAML AuthnRequest to initiate 
    # an authentication process. 
    default "https://login.microsoftonline.com/8807dced-9637-4205-a520-423077750c60/saml2"; 
} 

map $host $saml_idp_verification_certificate { 
    # Certificate file that will be used to verify the digital signature 
    # on the SAML Response, LogoutRequest or LogoutResponse received from IdP. 
    # Must be public key in PKCS#1 format. See documentation on how to convert 
    # X.509 PEM to DER format. 
    default "/etc/nginx/conf.d/demonginx.spki"; 
} 

######### Single Logout (SLO) ######### 

map $host $saml_sp_slo_url { 
    # SP endpoint that the IdP will send the SAML LogoutRequest to initiate 
    # a logout process or LogoutResponse to confirm the logout. 
    default "https://dev.sports.com/saml/sls"; 
} 

map $host $saml_sp_slo_binding { 
    # Refers to the method by which a LogoutRequest or LogoutResponse 
    # is sent from the SP to an IdP during the Single Logout (SLO) process. 
    # Only HTTP-POST or HTTP-Redirect methods are allowed. 
    default 'HTTP-POST'; 
} 

map $host $saml_sp_sign_slo { 
    # Whether the SP must sign the LogoutRequest or LogoutResponse 
    # sent to the IdP. 
    default "false"; 
} 

map $host $saml_idp_slo_url { 
    # IdP endpoint that the SP will send the LogoutRequest to initiate 
    # a logout process or LogoutResponse to confirm the logout. 
    # If not set, the SAML Single Logout (SLO) feature is DISABLED and 
    # requests to the 'logout' location will result in the termination 
    # of the user session and a redirect to the logout landing page. 
    default "https://login.microsoftonline.com/8807dced-9637-4205-a520-423077750c60/saml2"; 
} 

map $host $saml_sp_want_signed_slo { 
    # Whether the SP wants the SAML LogoutRequest or LogoutResponse from the IdP 
    # to be digitally signed. 
    default "true"; 
} 

map $host $saml_logout_landing_page { 
    # Where to redirect user after requesting /logout location. This can be 
    # replaced with a custom logout page, or complete URL. 
    default "/_logout"; # Built-in, simple logout page 
} 

map $proto $saml_cookie_flags { 
    http  "Path=/; SameSite=lax;"; # For HTTP/plaintext testing 
    https "Path=/; SameSite=lax; HttpOnly; Secure;"; # Production recommendation 
} 

map $http_x_forwarded_port $redirect_base { 
    ""      $proto://$host:$server_port; 
    default $proto://$host:$http_x_forwarded_port; 
} 

map $http_x_forwarded_proto $proto { 
    ""      $scheme; 
    default $http_x_forwarded_proto; 
} 
# ADVANCED CONFIGURATION BELOW THIS LINE 
# Additional advanced configuration (server context) in saml_sp.server_conf 

######### Shared memory zones that keep the SAML-related key-value databases 

# Zone for storing AuthnRequest and LogoutRequest message identifiers (ID) 
# to prevent replay attacks. (REQUIRED) 
# Timeout determines how long the SP waits for a response from the IDP, 
# i.e. how long the user authentication process can take. 
keyval_zone zone=saml_request_id:1M                 state=/var/lib/nginx/state/saml_request_id.json                  timeout=5m; 

# Zone for storing SAML Response message identifiers (ID) to prevent replay attacks. (REQUIRED) 
# Timeout determines how long the SP keeps IDs to prevent reuse. 
keyval_zone zone=saml_response_id:1M                state=/var/lib/nginx/state/saml_response_id.json                 timeout=1h; 

# Zone for storing SAML session access information. (REQUIRED) 
# Timeout determines how long the SP keeps session access decision (the session lifetime). 
keyval_zone zone=saml_session_access:1M             state=/var/lib/nginx/state/saml_session_access.json              timeout=1h; 

# Zone for storing SAML NameID values. (REQUIRED) 
# Timeout determines how long the SP keeps NameID values. Must be equal to session lifetime. 
keyval_zone zone=saml_name_id:1M                    state=/var/lib/nginx/state/saml_name_id.json                     timeout=1h; 

# Zone for storing SAML NameID format values. (REQUIRED) 
# Timeout determines how long the SP keeps NameID format values. Must be equal to session lifetime. 
keyval_zone zone=saml_name_id_format:1M             state=/var/lib/nginx/state/saml_name_id_format.json              timeout=1h; 

# Zone for storing SAML SessionIndex values. (REQUIRED) 
# Timeout determines how long the SP keeps SessionIndex values. Must be equal to session lifetime. 
keyval_zone zone=saml_session_index:1M              state=/var/lib/nginx/state/saml_session_index.json               timeout=1h; 
  
# Zone for storing SAML AuthnContextClassRef values. (REQUIRED) 
# Timeout determines how long the SP keeps AuthnContextClassRef values. Must be equal to session lifetime. 
keyval_zone zone=saml_authn_context_class_ref:1M    state=/var/lib/nginx/state/saml_authn_context_class_ref.json     timeout=1h; 

# Zones for storing SAML attributes values. (OPTIONAL) 
# Timeout determines how long the SP keeps attributes values. Must be equal to session lifetime. 
keyval_zone zone=saml_attrib_uid:1M                 state=/var/lib/nginx/state/saml_attrib_uid.json                  timeout=1h; 
keyval_zone zone=saml_attrib_name:1M                state=/var/lib/nginx/state/saml_attrib_name.json                 timeout=1h; 
keyval_zone zone=saml_attrib_memberOf:1M            state=/var/lib/nginx/state/saml_attrib_memberOf.json             timeout=1h; 

######### SAML-related variables whose value is looked up by the key (session cookie) in the key-value database. 

# Required: 
keyval $saml_request_id     $saml_request_redeemed          zone=saml_request_id;               # SAML Request ID 
keyval $saml_response_id    $saml_response_redeemed         zone=saml_response_id;              # SAML Response ID 
keyval $cookie_auth_token   $saml_access_granted            zone=saml_session_access;           # SAML Access decision 
keyval $cookie_auth_token   $saml_name_id                   zone=saml_name_id;                  # SAML NameID 
keyval $cookie_auth_token   $saml_name_id_format            zone=saml_name_id_format;           # SAML NameIDFormat 
keyval $cookie_auth_token   $saml_session_index             zone=saml_session_index;            # SAML SessionIndex 
keyval $cookie_auth_token   $saml_authn_context_class_ref   zone=saml_authn_context_class_ref;  # SAML AuthnContextClassRef 

# Optional: 
keyval $cookie_auth_token   $saml_attrib_uid                zone=saml_attrib_uid; 
keyval $cookie_auth_token   $saml_attrib_name               zone=saml_attrib_name; 
keyval $cookie_auth_token   $saml_attrib_memberOf           zone=saml_attrib_memberOf; 
 

keyval_zone    zone=saml_attrib_mail:1M                state=/var/lib/nginx/state/saml_attrib_mail.json   timeout=1h; 
keyval         $cookie_auth_token $saml_attrib_mail    zone=saml_attrib_mail; 
  
keyval $cookie_auth_token   $saml_attrib_objectid           zone=saml_attrib_objectid; 
keyval_zone zone=saml_attrib_objectid:1M            state=/var/lib/nginx/state/saml_attrib_objectid.json             timeout=1h; 
  

######### Imports a module that implements SAML SSO and SLO functionality 
js_import samlsp from conf.d/saml_sp.js; 

127.0.0.1 - - [14/Aug/2023:21:25:49 +0000] "GET / HTTP/1.0" 200 127 "https://login.microsoftonline.com/" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/16.1 Safari/605.1.15" "-" 

99.187.244.63 - Akash Ananthanarayanan [14/Aug/2023:21:25:49 +0000] "GET / HTTP/1.1" "dev.sports.com" 200 127 "https://login.microsoftonline.com/" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/16.1 Safari/605.1.15" "- 

2023/08/14 21:25:49 [info] 27513#27513: *399 js: SAML SP success, creating session _d4db9b93c415ee7b4e057a4bb195df6cd0be7e4d