Contents

HTTPS--HTTP Server and Client with SSL 3.0

The HTTPS--HTTP Server and Client with SSL 3.0 feature provides Secure Socket Layer (SSL) version 3.0 support for the HTTP 1.1 server and HTTP 1.1 client within Cisco IOS XE software. SSL provides server authentication, encryption, and message integrity to allow secure HTTP communications. SSL also provides HTTP client authentication. HTTP over SSL is abbreviated as HTTPS.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

Information About HTTPS--HTTP Server and Client with SSL 3.0

To configure the HTTP with SSL 3.0 (HTTPS) feature, you should understand the following concepts:

Secure HTTP Server and Secure HTTP Client

A secure HTTP connection means that data sent to and received from an HTTP server are encrypted before being sent out over the Internet. HTTP with SSL encryption provides a secure connection to allow such functions as configuring a router from a web browser. Cisco’s implementation of the secure HTTP server and secure HTTP client uses an implementation of the SSL version 3.0. Application layer encryption provides an alternative to older methods such as having to set up a tunnel to the HTTP server for remote management. HTTP over SSL is abbreviated as HTTPS; the URL of a secure connection will begin with https:// instead of http://.

The Cisco IOS XE HTTP secure server’s primary role is to listen for HTTPS requests on a designated port (the default HTTPS port is 443) and to pass the request to the HTTP 1.1 web server. The HTTP 1.1 server processes requests and passes responses (served pages) back to the HTTP secure server, which, in turn, responds to the original request.

The Cisco IOS XE HTTP secure client’s primary role is to respond to Cisco IOS XE application requests for HTTPS User Agent services, perform HTTPS User Agent services on the application’s behalf, and pass the response back to the application.

Certificate Authority Trustpoints

Certificate authorities (CAs) are responsible for managing certificate requests and issuing certificates to participating IPSec network devices. These services provide centralized security key and certificate management for the participating devices. Specific CA servers are referred to as “trustpoints.”

The HTTPS server provides a secure connection by providing a certified X.509v3 certificate to the client when a connection attempt is made. The certified X.509v3 certificate is obtained from a specified CA trustpoint. The client (usually a web browser), in turn, has a public key that allows it to authenticate the certificate.

Configuring a CA trustpoint is highly recommended for secure HTTP connections. However, if a CA trustpoint is not configured for the routing device running the HTTPS server, the server will certify itself and generate the needed RSA key pair. Because a self-certified (self-signed) certificate does not provide adequate security, the connecting client will generate a notification that the certificate is self-certified, and the user will have the opportunity to accept or reject the connection. This option is available for internal network topologies (such as testing).

The HTTPS--HTTP Server and Client with SSL 3.0 feature also provides an optional command (ip http secure-client-auth) that, when enabled, has the HTTPS server request an X.509v3 certificate from the client. Authenticating the client provides more security than server authentication by itself.

For additional information on certificate authorities, see the “Configuring Certification Authority Interoperability” chapter in the Cisco IOS XE Security Configuration Guide .

CipherSuites

A CipherSuite specifies the encryption algorithm and digest algorithm to use on an SSL connection. Web browsers offer a list of supported CipherSuites when connecting to the HTTPS server, and the client and server will negotiate the best encryption algorithm to use from those that are supported by both. For example, Netscape Communicator 4.76 supports U.S. security with RSA Public Key Cryptography, MD2, MD5, RC2-CBC, RC4, DES-CBC, and DES-EDE3-CBC.

For the best possible encryption, you should use a browser that supports 128-bit encryption, such as Microsoft Internet Explorer version 5.5 (or later), or Netscape Communicator version 4.76 (or later). The SSL_RSA_WITH_DES_CBC_SHA CipherSuite provides less security than the other CipherSuites, because it does not offer 128-bit encryption.

In terms of router processing load (speed), the following list ranks the CipherSuites from fastest to slowest (slightly more processing time is required for the more secure and more complex CipherSuites):

  1. SSL_RSA_WITH_DES_CBC_SHA
  2. SSL_RSA_WITH_RC4_128_MD5
  3. SSL_RSA_WITH_RC4_128_SHA
  4. SSL_RSA_WITH_3DES_EDE_CBC_SHA

How to Configure the HTTPS--HTTP Server and Client with SSL 3.0

Declaring a Certificate Authority Trustpoint

Configuring a CA trustpoint is highly recommended for secure HTTP connections. The certified X.509v3 certificate for the secure HTTP server (or client) is obtained from the specified CA trustpoint. If you do not declare a CA trustpoint, then a self-signed certificate will be used for secure HTTP connections. The self-signed certificate is generated automatically.

SUMMARY STEPS

    1.    enable

    2.    configure terminal

    3.    hostname name

    4.    ip domain-name name

    5.    crypto key generate rsa usage-keys

    6.    crypto ca trustpoint name

    7.    enrollment url url

    8.    enrollment http-proxy host-name port-number

    9.    crl {query url | optional | best-effort}

    10.    primary

    11.    exit

    12.    crypto ca authenticate name

    13.    crypto ca enrollment name

    14.    Do one of the following:

    • copy running-config startup-config
    • copy system:running-config nvram:startup-config


DETAILED STEPS
     Command or ActionPurpose
    Step 1 enable


    Example:
    Router> enable
     

    Enables privileged EXEC mode.

    • Enter your password if prompted.
     
    Step 2 configure terminal


    Example:
    Router# configure terminal
     

    Enters global configuration mode.

     
    Step 3 hostname name


    Example:
    Router(config)# hostname Router
     

    Specifies the hostname of the router.

    • This step is needed only if you have not previously configured a hostname for your router. The hostname is required because a fully qualified domain name is needed for security keys and certificates.
     
    Step 4 ip domain-name name


    Example:
    Router(config)# ip domain-name example.com
     

    Specifies the IP domain name of the router.

    • This step is needed only if you have not previously configured an IP domain name for your router. The domain name is required because a fully qualified domain name is needed for security keys and certificates.
     
    Step 5 crypto key generate rsa usage-keys


    Example:
    Router(config)# crypto key generate rsa usage-keys
     

    (Optional) Generates an RSA key pair.

    • The usage-keys keyword specifies that two RSA special-usage key pairs should be generated (that is, one encryption pair and one signature pair) instead of one general-purpose key pair.
    • RSA key pairs are used to sign and encrypt Internet key exchange (IKE) key management messages and are required before you can obtain a certificate for your router.
    • RSA key pairs are generated automatically. This command can be used to regenerate the keys, if needed.
    Note   

    There are other keywords and arguments for this command, but they do not pertain to this feature.

     
    Step 6 crypto ca trustpoint name


    Example:
    Router(config)# crypto ca trustpoint TP1
     

    Specifies a local configuration name for the CA trustpoint and enters CA trustpoint configuration mode.

    Note   

    The crypto ca identity command was replaced by the crypto ca trustpoint command.

     
    Step 7 enrollment url url


    Example:
    Router(ca-trustpoint)# enrollment url http://example.com
     

    Specifies a URL of the CA where your router should send certificate requests.

    • If you are using Simple Certificate Enrollment Protocol (SCEP) for enrollment, the URL argument must be in the form http://CA-name , where CA-name is the host Domain Name System (DNS) name or IP address of the CA trustpoint.
     
    Step 8 enrollment http-proxy host-name port-number


    Example:
    Router(ca-trustpoint)# enrollment http-proxy example.com 8080
     

    (Optional) Configures the router to obtain certificates from the CA through an HTTP proxy server.

     
    Step 9 crl {query url | optional | best-effort}


    Example:
    Router(ca-trustpoint)# crl query ldap://example.com
     

    Configures the router to request a certificate revocation list (CRL), make CRL checking optional, or perform CRL checking on a “best-effort” basis.

    • CRLs ensure that the certificate of the peer has not been revoked.
    • The crl optional command configures the router to accept certificates even if the appropriate CRL cannot be downloaded.
    • Use the crl query url command to specify the Lightweight Directory Access Protocol (LDAP) URL of the CA server; for example, ldap://another-server.
     
    Step 10 primary


    Example:
    Router(ca-trustpoint)# primary 
     

    (Optional) Specifies that this trustpoint should be used as the primary (default) trustpoint for CA requests.

    • Use this command if more than one CA trustpoint will be configured on this router.
     
    Step 11 exit


    Example:
    Router(ca-trustpoint)# exit
     

    Exits CA trustpoint configuration mode and returns to global configuration mode.

     
    Step 12 crypto ca authenticate name


    Example:
    Router(config)# crypto ca authenticate TP1
     

    Authenticates the CA by getting the public key of the CA.

    • Use the same name that you used when declaring the CA in the crypto ca trustpoint command.
     
    Step 13 crypto ca enrollment name


    Example:
    Router(config)# crypto ca enrollment TP1
     

    Obtains the certificate from the specified CA trustpoint.

    • This command requests a signed certificate from the CA for each RSA key pair.
     
    Step 14Do one of the following:
    • copy running-config startup-config
    • copy system:running-config nvram:startup-config


    Example:
    Router(config)# copy running-config startup-config
     

    Saves the configuration to NVRAM.

    • This command is required to save the certificates into NVRAM. If not used, the certificates would be lost at router reload.
    Note   

    To execute EXEC mode commands in global configuration mode, you can add the do keyword before the command. For example, instead of copy running-config startup-config, you could enter do copy running-config startup-config.

     

    Configuring the HTTPS Server with SSL 3.0

    To disable the standard HTTP server and configure the HTTPS server with SSL 3.0, complete the procedure in this section.

    Before You Begin

    If a certificate authority is to be used for certification, you should declare the CA trustpoint on the routing device before enabling the secure HTTP server.

    SUMMARY STEPS

      1.    enable

      2.    Router# show ip http server status

      3.    configure terminal

      4.    no ip http server

      5.    ip http secure-server

      6.    ip http secure-port port-number

      7.    ip http secure-ciphersuite [3des-ede-cbc-sha] [rc4-128-sha] [rc4-128-md5] [des-cbc-sha]

      8.    ip http secure-client-auth

      9.    ip http secure-trustpoint name

      10.    end

      11.    show ip http server secure status


    DETAILED STEPS
       Command or ActionPurpose
      Step 1 enable


      Example:
      Router> enable
       

      Enables privileged EXEC mode.

      • Enter your password if prompted.
       
      Step 2 Router# show ip http server status

      Example:
      Router# show ip http server status


      Example:
      
      
              
       

      (Optional) Displays the status of the HTTP server.

      • If you are unsure whether the secure HTTP server is supported in the software image you are running, enter this command and look for the line “HTTP secure server capability: {Present | Not present}”.
      • This command displays the status of the standard HTTP server (enabled or disabled).
       
      Step 3 configure terminal


      Example:
      Router# configure terminal 
       

      Enters global configuration mode.

       
      Step 4 no ip http server


      Example:
      Router(config)# no ip http server
       

      Disables the standard HTTP server.

      Note   

      When enabling the HTTPS server you should always disable the standard HTTP server to prevent insecure connections to the same services. This is a precautionary step (typically, the HTTP server is disabled by default).

       
      Step 5 ip http secure-server


      Example:
      Router(config)# ip http secure-server
       

      Enables the HTTPS server.

       
      Step 6 ip http secure-port port-number


      Example:
      Router(config)# ip http secure-port 1025
       

      (Optional) Specifies the port number that should be used for the HTTPS server. The default port number is 443. Valid options are 443 or any number in the range 1025 to 65535.

       
      Step 7 ip http secure-ciphersuite [3des-ede-cbc-sha] [rc4-128-sha] [rc4-128-md5] [des-cbc-sha]


      Example:
      Router(config)# ip http secure-ciphersuite rc4-128-sha rc4-128-md5 
       

      (Optional) Specifies the CipherSuites (encryption algorithms) that should be used for encryption over the HTTPS connection.

      • This command allows you to restrict the list of CipherSuites that the server offers the connecting clients. For example, you may want to allow only the most secure CipherSuite to be used.
      • Unless you have a reason to specify the CipherSuites that should be used, or you are unfamiliar with the details of these CipherSuites, you should leave this command unconfigured and let the server and client negotiate the CipherSuite that they both support (this is the default).
       
      Step 8 ip http secure-client-auth


      Example:
      Router(config)# ip http secure-client-auth
       

      (Optional) Configures the HTTP server to request an X.509v3 certificate from the client in order to authenticate the client during the connection process.

      • In the default connection and authentication process, the client requests a certificate from the HTTP server, but the server does not attempt to authenticate the client. Authenticating the client provides more security than server authentication by itself, but not all clients may be configured for CA authentication.
       
      Step 9 ip http secure-trustpoint name


      Example:
      Router(config)# ip http secure-trustpoint trustpoint-01
       

      Specifies the CA trustpoint that should be used to obtain an X.509v3 security certificate and to authenticate the connecting client’s certificate.

      • Use of this command assumes you have already declared a CA trustpoint using the crypto ca trustpoint command and associated submode commands.
      • Use the same trustpoint name that you used in the associated crypto ca trustpoint command.
       
      Step 10 end


      Example:
      Router(config)# end
       

      Ends the current configuration session and returns you to privileged EXEC mode.

       
      Step 11 show ip http server secure status


      Example:
      Router# show ip http server secure status
       

      Displays the status of the HTTP secure server configuration.

       

      Verifying the Configuration of the HTTPS Server

      To verify the configuration of the HTTPS server, connect to the router running the HTTPS server with a web browser by entering https://url , where url is the IP address or hostname of the router. Successful connection using the https prefix (instead of the standard http) indicates that the HTTPS server is configured properly. If a port other than the default port is configured (using the ip http secure-port command), you must also specify the port number after the URL. For example:

      https://209.165.202.129:1026 

      or

      https://host.domain.com:1026 
      

      Generally, you can verify that the HTTPS server is configured and that you have a secure connection by locating an image of a padlock at the bottom of your browser window. Also note that secure HTTP connections have a URL that starts with “https:” instead of “http:”.

      Providing Additional Security and Efficiency

      The configuration of the standard HTTP server applies to the secure HTTP server as well. To provide additional security and efficiency to both the standard HTTP server and the HTTPS server, complete the procedure in this section.

      SUMMARY STEPS

        1.    enable

        2.    configure terminal

        3.    ip http path path-name

        4.    ip http access-class access-list-number

        5.    ip http max-connections value

        6.    ip http timeout-policy idle seconds life seconds requests value


      DETAILED STEPS
         Command or ActionPurpose
        Step 1 enable


        Example:
        Router> enable
         

        Enables privileged EXEC mode.

        • Enter your password if prompted.
         
        Step 2 configure terminal


        Example:
        Router# configure terminal 
         

        Enters global configuration mode.

         
        Step 3 ip http path path-name


        Example:
        Router(config)# ip http path slot1:
         

        (Optional) Sets the base HTTP path for HTML files.

        • The base path is used to specify the location of the HTTP server files (HTML files) on the local system. Generally, the HTML files are located in system flash memory.
         
        Step 4 ip http access-class access-list-number


        Example:
        Router(config)# ip http access-class 20
         

        (Optional) Specifies the access list that should be used to allow access to the HTTP server.

         
        Step 5 ip http max-connections value


        Example:
        Router(config)# ip http max-connections 10
         

        (Optional) Sets the maximum number of concurrent connections to the HTTP server that will be allowed. The default value is 5.

         
        Step 6 ip http timeout-policy idle seconds life seconds requests value


        Example:
        Router(config)# ip http timeout-policy idle 30 life 120 requests 100 
         

        (Optional) Sets the characteristics that determine how long a connection to the HTTP server should remain open. The characteristics are:

        • idle --The maximum number of seconds the connection will be kept open if no data is received or response data cannot be sent out on the connection. Note that a new value may not take effect on any already existing connections. If the server is too busy or the limit on the life time or the number of requests is reached, the connection may be closed sooner. The default value is 180 seconds (3 minutes).
        • life --The maximum number of seconds the connection will be kept open, from the time the connection is established. Note that the new value may not take effect on any already existing connections. If the server is too busy or the limit on the idle time or the number of requests is reached, it may close the connection sooner. Also, because the server will not close the connection while actively processing a request, the connection may remain open longer than the specified life time if processing is occurring when the life maximum is reached. In this case, the connection will be closed when processing finishes. The default value is 180 seconds (3 minutes). The maximum value is 86,400 seconds (24 hours).
        • requests --The maximum limit on the number of requests processed on a persistent connection before it is closed. Note that the new value may not take effect on any already existing connections. If the server is too busy or the limit on the idle time or the life time is reached, the connection may be closed before the maximum number of requests are processed. The default value is 1. The maximum value is 86,400.
         

        Configuring the HTTPS Client with SSL 3.0

        To configure the HTTPS client with SSL 3.0, complete the procedure in this section.

        Before You Begin

        The standard HTTP client and the secure HTTP client are always enabled.

        A certificate authority is required for secure HTTP client certification; the following steps assume that you have previously declared a CA trustpoint on the routing device. If a CA trustpoint is not configured, and the remote HTTPS server requires client authentication, connections to the secure HTTP client will fail.

        SUMMARY STEPS

          1.    enable

          2.    configure terminal

          3.    ip http client secure-trustpoint trustpoint-name

          4.    ip http client secure-ciphersuite [3des-ede-cbc-sha] [rc4-128-sha] [rc4-128-md5] [des-cbc-sha]

          5.    end

          6.    show ip http client secure status


        DETAILED STEPS
           Command or ActionPurpose
          Step 1 enable


          Example:
          Router> enable
           

          Enables privileged EXEC mode.

          • Enter your password if prompted.
           
          Step 2 configure terminal


          Example:
          Router# configure terminal 
           

          Enters global configuration mode.

           
          Step 3 ip http client secure-trustpoint trustpoint-name


          Example:
          Router(config)# ip http client secure-trustpoint trustpoint01
           

          (Optional) Specifies the CA trustpoint that should be used if the remote HTTP server requests client authentication.

          • Use of this command assumes you have already declared a CA trustpoint using the crypto ca trustpoint command and associated submode commands.
          • Use the same trustpoint name that you used in the associated crypto ca trustpoint command.
          • This command is optional if client authentication is not needed, or if a primary trustpoint has been configured. If the ip http client secure-trustpoint command is not used, the router will use the primary trustpoint, as specified by the primaryCA trustpoint configuration mode command.
           
          Step 4 ip http client secure-ciphersuite [3des-ede-cbc-sha] [rc4-128-sha] [rc4-128-md5] [des-cbc-sha]


          Example:
          Router(config)# ip http client secure-ciphersuite rc4-128-sha rc4-128-md5 
           

          (Optional) Specifies the CipherSuites (encryption algorithms) that should be used for encryption over the HTTPS connection.

          • This command allows you to restrict the list of CipherSuites that the client offers when connecting to a secure HTTP server. For example, you may want to allow only the most secure CipherSuites to be used.
          • Unless you have a reason to specify the CipherSuites that should be used, or you are unfamiliar with the details of these CipherSuites, you should leave this command unconfigured and let the server and client negotiate the CipherSuite that they both support (this is the default).
           
          Step 5 end


          Example:
          Router(config)# end
           

          Ends the current configuration session and returns to privileged EXEC mode.

           
          Step 6 show ip http client secure status


          Example:
          Router# show ip http client secure status
           

          Displays the status of the HTTP secure server configuration.

           

          Configuration Examples for the HTTPS--HTTP Server and Client with SSL 3.0 feature

          The following example shows a configuration session in which the secure HTTP server is enabled, the port for the secure HTTP server is configured as 1025, and the remote CA trustpoint server “CA-trust-local” is used for certification.

          Router# show ip http server status
           
          HTTP server status: Disabled
          HTTP server port: 80
          HTTP server authentication method: enable
          HTTP server access class: 0
          HTTP server base path: 
          Maximum number of concurrent server connections allowed: 5
          Server idle time-out: 600 seconds
          Server life time-out: 600 seconds
          Maximum number of requests allowed on a connection: 1
          HTTP secure server capability: Present
          HTTP secure server status: Disabled
          HTTP secure server port: 443
          HTTP secure server ciphersuite: 3des-ede-cbc-sha des-cbc-sha rc4-128-md5 rc4-12a
          HTTP secure server client authentication: Disabled
          HTTP secure server trustpoint: 
          Router# configure terminal
           
          Enter configuration commands, one per line.  End with CNTL/Z.
          Router(config)# ip http secure-server
           
          Router(config)# ip http client secure-trustpoint CA-trust-local
           
          Router(config)# ip http secure-port 1024
           
          Invalid secure port value.
          Router(config)# ip http secure-port 1025
           
          Router(config)# ip http secure-ciphersuite rc4-128-sha rc4-128-md5 
          Router(config)# end
          
          Router# show ip http server secure status
          HTTP secure server status: Enabled
          HTTP secure server port: 1025
          HTTP secure server ciphersuite: rc4-128-md5 rc4-128-sha
          HTTP secure server client authentication: Disabled
          HTTP secure server trustpoint: CA-trust-local
          

          In the following example, the CA trustpoint CA-trust-local is specified, and the HTTPS client is configured to use this trustpoint for client authentication requests:

          Router# config terminal
          Enter configuration commands, one per line.  End with CNTL/Z.
          Router(config)# crypto ca trustpoint CA-trust-local
           
          Router(ca-trustpoint)# enrollment url http://example.com
           
          Router(ca-trustpoint)# crl query ldap://example.com
           
          Router(ca-trustpoint)# primary
           
          Router(ca-trustpoint)# exit
           
          Router(config)# ip http client secure-trustpoint CA-trust-local
           
          Router(config)# end
           
          Router# copy running-config startup-config
           

          Additional References

          The following sections provide references related to the HTTPS--HTTP Server and Client with SSL 3.0 feature.

          Related Documents

          Related Topic

          Document Title

          SSL 3.0

          The SSL Protocol Version 3.0

          This document is available from various sources online.

          Standard Cisco Web Client

          HTTP 1.1 Web Client

          Standard Cisco Web Server

          HTTP 1.1 Web Server

          Certification Authority Interoperability

          • Configuring Certification Authority Interoperability
          • Certificate Autoenrollment
          • Certificate Enrollment Enhancements
          • Trustpoint CLI
          • Source Interface Selection for Outgoing Traffic with Certificate Authority

          Standards

          Standard

          Title

          No new or modified standards are supported by this feature.

          --

          Related MIBs

          MIBs

          MIBs Link

          • No new or modified MIBs are supported by this feature and support for existing MIBs has not been modified by this feature.

          To locate and download MIBs for selected platforms, Cisco IOS XE releases, and feature sets, use Cisco MIB Locator found at the following URL:

          http:/​/​www.cisco.com/​go/​mibs

          Related RFCs

          RFCs

          Description

          RFC 2616

          Cisco’s implementation of HTTP is based on RFC 2616: Hypertext Transfer Protocol -- HTTP/1.1 .

          Technical Assistance

          Description

          Link

          The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies.

          To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds.

          Access to most tools on the Cisco Support website requires a Cisco.com user ID and password.

          http:/​/​www.cisco.com/​techsupport

          Feature Information for HTTPS--HTTP Server and Client with SSL 3.0

          The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

          Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

          Table 1 Feature Information for HTTPS--HTTP Server and Client with SSL 3.0

          Feature Name

          Releases

          Feature Information

          HTTPS--HTTP Server and Client with SSL 3.0

          Cisco IOS XE Release 2.1

          This feature provides Secure Socket Layer (SSL) version 3.0 support for the HTTP 1.1 server and HTTP 1.1 client within Cisco IOS XE software. SSL provides server authentication, encryption, and message integrity to allow secure HTTP communications. SSL also provides HTTP client authentication.

          This feature is supported only in Cisco software images that support SSL. Specifically, SSL is supported in “IPSec 56” and “IPSec 3DES” images (contains “k8” or “k9” in the image name).

          The following commands are introduced or modified in the feature or features documented in this module.

          • debug ip http ssl error
          • ip http client secure-ciphersuite
          • ip http client secure-trustpoint
          • ip http secure-ciphersuite
          • ip http secure-client-auth
          • ip http secure-port
          • ip http secure-server
          • ip http secure-trustpoint
          • show ip http client secure status
          • show ip http server secure status

          Glossary

          RSA--RSA is a widely used Internet encryption and authentication system that uses public and private keys for encryption and decryption. The RSA algorithm was invented in 1978 by Ron Rivest, Adi Shamir, and Leonard Adleman. The abbreviation RSA comes from the first letter of the last names of the three original developers. The RSA algorithm is included in many applications, such as the web browsers from Microsoft and Netscape. The RSA encryption system is owned by RSA Security.

          SHA --The Secure Hash Algorithm. SHA was developed by NIST and is specified in the Secure Hash Standard (SHS, FIPS 180). Often used as an alternative to Digest 5 algorithm.

          signatures, digital--In the context of SSL, “signing” means to encrypt with a private key. In digital signing, one-way hash functions are used as input for a signing algorithm. In RSA signing, a 36-byte structure of two hashes (one SHA and one MD5) is signed (encrypted with the private key).

          SSL 3.0--Secure Socket Layer version 3.0. SSL is a security protocol that provides communications privacy over the Internet. The protocol allows client and server applications to communicate in a way that is designed to prevent eavesdropping, tampering, or message forgery. SSL uses a program layer located between the Internet’s HTTP and TCP layers. SSL is included as part of most web server products and as part of most Internet browsers.


          HTTPS--HTTP Server and Client with SSL 3.0

          HTTPS--HTTP Server and Client with SSL 3.0

          The HTTPS--HTTP Server and Client with SSL 3.0 feature provides Secure Socket Layer (SSL) version 3.0 support for the HTTP 1.1 server and HTTP 1.1 client within Cisco IOS XE software. SSL provides server authentication, encryption, and message integrity to allow secure HTTP communications. SSL also provides HTTP client authentication. HTTP over SSL is abbreviated as HTTPS.

          Finding Feature Information

          Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

          Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

          Information About HTTPS--HTTP Server and Client with SSL 3.0

          To configure the HTTP with SSL 3.0 (HTTPS) feature, you should understand the following concepts:

          Secure HTTP Server and Secure HTTP Client

          A secure HTTP connection means that data sent to and received from an HTTP server are encrypted before being sent out over the Internet. HTTP with SSL encryption provides a secure connection to allow such functions as configuring a router from a web browser. Cisco’s implementation of the secure HTTP server and secure HTTP client uses an implementation of the SSL version 3.0. Application layer encryption provides an alternative to older methods such as having to set up a tunnel to the HTTP server for remote management. HTTP over SSL is abbreviated as HTTPS; the URL of a secure connection will begin with https:// instead of http://.

          The Cisco IOS XE HTTP secure server’s primary role is to listen for HTTPS requests on a designated port (the default HTTPS port is 443) and to pass the request to the HTTP 1.1 web server. The HTTP 1.1 server processes requests and passes responses (served pages) back to the HTTP secure server, which, in turn, responds to the original request.

          The Cisco IOS XE HTTP secure client’s primary role is to respond to Cisco IOS XE application requests for HTTPS User Agent services, perform HTTPS User Agent services on the application’s behalf, and pass the response back to the application.

          Certificate Authority Trustpoints

          Certificate authorities (CAs) are responsible for managing certificate requests and issuing certificates to participating IPSec network devices. These services provide centralized security key and certificate management for the participating devices. Specific CA servers are referred to as “trustpoints.”

          The HTTPS server provides a secure connection by providing a certified X.509v3 certificate to the client when a connection attempt is made. The certified X.509v3 certificate is obtained from a specified CA trustpoint. The client (usually a web browser), in turn, has a public key that allows it to authenticate the certificate.

          Configuring a CA trustpoint is highly recommended for secure HTTP connections. However, if a CA trustpoint is not configured for the routing device running the HTTPS server, the server will certify itself and generate the needed RSA key pair. Because a self-certified (self-signed) certificate does not provide adequate security, the connecting client will generate a notification that the certificate is self-certified, and the user will have the opportunity to accept or reject the connection. This option is available for internal network topologies (such as testing).

          The HTTPS--HTTP Server and Client with SSL 3.0 feature also provides an optional command (ip http secure-client-auth) that, when enabled, has the HTTPS server request an X.509v3 certificate from the client. Authenticating the client provides more security than server authentication by itself.

          For additional information on certificate authorities, see the “Configuring Certification Authority Interoperability” chapter in the Cisco IOS XE Security Configuration Guide .

          CipherSuites

          A CipherSuite specifies the encryption algorithm and digest algorithm to use on an SSL connection. Web browsers offer a list of supported CipherSuites when connecting to the HTTPS server, and the client and server will negotiate the best encryption algorithm to use from those that are supported by both. For example, Netscape Communicator 4.76 supports U.S. security with RSA Public Key Cryptography, MD2, MD5, RC2-CBC, RC4, DES-CBC, and DES-EDE3-CBC.

          For the best possible encryption, you should use a browser that supports 128-bit encryption, such as Microsoft Internet Explorer version 5.5 (or later), or Netscape Communicator version 4.76 (or later). The SSL_RSA_WITH_DES_CBC_SHA CipherSuite provides less security than the other CipherSuites, because it does not offer 128-bit encryption.

          In terms of router processing load (speed), the following list ranks the CipherSuites from fastest to slowest (slightly more processing time is required for the more secure and more complex CipherSuites):

          1. SSL_RSA_WITH_DES_CBC_SHA
          2. SSL_RSA_WITH_RC4_128_MD5
          3. SSL_RSA_WITH_RC4_128_SHA
          4. SSL_RSA_WITH_3DES_EDE_CBC_SHA

          How to Configure the HTTPS--HTTP Server and Client with SSL 3.0

          Declaring a Certificate Authority Trustpoint

          Configuring a CA trustpoint is highly recommended for secure HTTP connections. The certified X.509v3 certificate for the secure HTTP server (or client) is obtained from the specified CA trustpoint. If you do not declare a CA trustpoint, then a self-signed certificate will be used for secure HTTP connections. The self-signed certificate is generated automatically.

          SUMMARY STEPS

            1.    enable

            2.    configure terminal

            3.    hostname name

            4.    ip domain-name name

            5.    crypto key generate rsa usage-keys

            6.    crypto ca trustpoint name

            7.    enrollment url url

            8.    enrollment http-proxy host-name port-number

            9.    crl {query url | optional | best-effort}

            10.    primary

            11.    exit

            12.    crypto ca authenticate name

            13.    crypto ca enrollment name

            14.    Do one of the following:

            • copy running-config startup-config
            • copy system:running-config nvram:startup-config


          DETAILED STEPS
             Command or ActionPurpose
            Step 1 enable


            Example:
            Router> enable
             

            Enables privileged EXEC mode.

            • Enter your password if prompted.
             
            Step 2 configure terminal


            Example:
            Router# configure terminal
             

            Enters global configuration mode.

             
            Step 3 hostname name


            Example:
            Router(config)# hostname Router
             

            Specifies the hostname of the router.

            • This step is needed only if you have not previously configured a hostname for your router. The hostname is required because a fully qualified domain name is needed for security keys and certificates.
             
            Step 4 ip domain-name name


            Example:
            Router(config)# ip domain-name example.com
             

            Specifies the IP domain name of the router.

            • This step is needed only if you have not previously configured an IP domain name for your router. The domain name is required because a fully qualified domain name is needed for security keys and certificates.
             
            Step 5 crypto key generate rsa usage-keys


            Example:
            Router(config)# crypto key generate rsa usage-keys
             

            (Optional) Generates an RSA key pair.

            • The usage-keys keyword specifies that two RSA special-usage key pairs should be generated (that is, one encryption pair and one signature pair) instead of one general-purpose key pair.
            • RSA key pairs are used to sign and encrypt Internet key exchange (IKE) key management messages and are required before you can obtain a certificate for your router.
            • RSA key pairs are generated automatically. This command can be used to regenerate the keys, if needed.
            Note   

            There are other keywords and arguments for this command, but they do not pertain to this feature.

             
            Step 6 crypto ca trustpoint name


            Example:
            Router(config)# crypto ca trustpoint TP1
             

            Specifies a local configuration name for the CA trustpoint and enters CA trustpoint configuration mode.

            Note   

            The crypto ca identity command was replaced by the crypto ca trustpoint command.

             
            Step 7 enrollment url url


            Example:
            Router(ca-trustpoint)# enrollment url http://example.com
             

            Specifies a URL of the CA where your router should send certificate requests.

            • If you are using Simple Certificate Enrollment Protocol (SCEP) for enrollment, the URL argument must be in the form http://CA-name , where CA-name is the host Domain Name System (DNS) name or IP address of the CA trustpoint.
             
            Step 8 enrollment http-proxy host-name port-number


            Example:
            Router(ca-trustpoint)# enrollment http-proxy example.com 8080
             

            (Optional) Configures the router to obtain certificates from the CA through an HTTP proxy server.

             
            Step 9 crl {query url | optional | best-effort}


            Example:
            Router(ca-trustpoint)# crl query ldap://example.com
             

            Configures the router to request a certificate revocation list (CRL), make CRL checking optional, or perform CRL checking on a “best-effort” basis.

            • CRLs ensure that the certificate of the peer has not been revoked.
            • The crl optional command configures the router to accept certificates even if the appropriate CRL cannot be downloaded.
            • Use the crl query url command to specify the Lightweight Directory Access Protocol (LDAP) URL of the CA server; for example, ldap://another-server.
             
            Step 10 primary


            Example:
            Router(ca-trustpoint)# primary 
             

            (Optional) Specifies that this trustpoint should be used as the primary (default) trustpoint for CA requests.

            • Use this command if more than one CA trustpoint will be configured on this router.
             
            Step 11 exit


            Example:
            Router(ca-trustpoint)# exit
             

            Exits CA trustpoint configuration mode and returns to global configuration mode.

             
            Step 12 crypto ca authenticate name


            Example:
            Router(config)# crypto ca authenticate TP1
             

            Authenticates the CA by getting the public key of the CA.

            • Use the same name that you used when declaring the CA in the crypto ca trustpoint command.
             
            Step 13 crypto ca enrollment name


            Example:
            Router(config)# crypto ca enrollment TP1
             

            Obtains the certificate from the specified CA trustpoint.

            • This command requests a signed certificate from the CA for each RSA key pair.
             
            Step 14Do one of the following:
            • copy running-config startup-config
            • copy system:running-config nvram:startup-config


            Example:
            Router(config)# copy running-config startup-config
             

            Saves the configuration to NVRAM.

            • This command is required to save the certificates into NVRAM. If not used, the certificates would be lost at router reload.
            Note   

            To execute EXEC mode commands in global configuration mode, you can add the do keyword before the command. For example, instead of copy running-config startup-config, you could enter do copy running-config startup-config.

             

            Configuring the HTTPS Server with SSL 3.0

            To disable the standard HTTP server and configure the HTTPS server with SSL 3.0, complete the procedure in this section.

            Before You Begin

            If a certificate authority is to be used for certification, you should declare the CA trustpoint on the routing device before enabling the secure HTTP server.

            SUMMARY STEPS

              1.    enable

              2.    Router# show ip http server status

              3.    configure terminal

              4.    no ip http server

              5.    ip http secure-server

              6.    ip http secure-port port-number

              7.    ip http secure-ciphersuite [3des-ede-cbc-sha] [rc4-128-sha] [rc4-128-md5] [des-cbc-sha]

              8.    ip http secure-client-auth

              9.    ip http secure-trustpoint name

              10.    end

              11.    show ip http server secure status


            DETAILED STEPS
               Command or ActionPurpose
              Step 1 enable


              Example:
              Router> enable
               

              Enables privileged EXEC mode.

              • Enter your password if prompted.
               
              Step 2 Router# show ip http server status

              Example:
              Router# show ip http server status


              Example:
              
              
                      
               

              (Optional) Displays the status of the HTTP server.

              • If you are unsure whether the secure HTTP server is supported in the software image you are running, enter this command and look for the line “HTTP secure server capability: {Present | Not present}”.
              • This command displays the status of the standard HTTP server (enabled or disabled).
               
              Step 3 configure terminal


              Example:
              Router# configure terminal 
               

              Enters global configuration mode.

               
              Step 4 no ip http server


              Example:
              Router(config)# no ip http server
               

              Disables the standard HTTP server.

              Note   

              When enabling the HTTPS server you should always disable the standard HTTP server to prevent insecure connections to the same services. This is a precautionary step (typically, the HTTP server is disabled by default).

               
              Step 5 ip http secure-server


              Example:
              Router(config)# ip http secure-server
               

              Enables the HTTPS server.

               
              Step 6 ip http secure-port port-number


              Example:
              Router(config)# ip http secure-port 1025
               

              (Optional) Specifies the port number that should be used for the HTTPS server. The default port number is 443. Valid options are 443 or any number in the range 1025 to 65535.

               
              Step 7 ip http secure-ciphersuite [3des-ede-cbc-sha] [rc4-128-sha] [rc4-128-md5] [des-cbc-sha]


              Example:
              Router(config)# ip http secure-ciphersuite rc4-128-sha rc4-128-md5 
               

              (Optional) Specifies the CipherSuites (encryption algorithms) that should be used for encryption over the HTTPS connection.

              • This command allows you to restrict the list of CipherSuites that the server offers the connecting clients. For example, you may want to allow only the most secure CipherSuite to be used.
              • Unless you have a reason to specify the CipherSuites that should be used, or you are unfamiliar with the details of these CipherSuites, you should leave this command unconfigured and let the server and client negotiate the CipherSuite that they both support (this is the default).
               
              Step 8 ip http secure-client-auth


              Example:
              Router(config)# ip http secure-client-auth
               

              (Optional) Configures the HTTP server to request an X.509v3 certificate from the client in order to authenticate the client during the connection process.

              • In the default connection and authentication process, the client requests a certificate from the HTTP server, but the server does not attempt to authenticate the client. Authenticating the client provides more security than server authentication by itself, but not all clients may be configured for CA authentication.
               
              Step 9 ip http secure-trustpoint name


              Example:
              Router(config)# ip http secure-trustpoint trustpoint-01
               

              Specifies the CA trustpoint that should be used to obtain an X.509v3 security certificate and to authenticate the connecting client’s certificate.

              • Use of this command assumes you have already declared a CA trustpoint using the crypto ca trustpoint command and associated submode commands.
              • Use the same trustpoint name that you used in the associated crypto ca trustpoint command.
               
              Step 10 end


              Example:
              Router(config)# end
               

              Ends the current configuration session and returns you to privileged EXEC mode.

               
              Step 11 show ip http server secure status


              Example:
              Router# show ip http server secure status
               

              Displays the status of the HTTP secure server configuration.

               

              Verifying the Configuration of the HTTPS Server

              To verify the configuration of the HTTPS server, connect to the router running the HTTPS server with a web browser by entering https://url , where url is the IP address or hostname of the router. Successful connection using the https prefix (instead of the standard http) indicates that the HTTPS server is configured properly. If a port other than the default port is configured (using the ip http secure-port command), you must also specify the port number after the URL. For example:

              https://209.165.202.129:1026 

              or

              https://host.domain.com:1026 
              

              Generally, you can verify that the HTTPS server is configured and that you have a secure connection by locating an image of a padlock at the bottom of your browser window. Also note that secure HTTP connections have a URL that starts with “https:” instead of “http:”.

              Providing Additional Security and Efficiency

              The configuration of the standard HTTP server applies to the secure HTTP server as well. To provide additional security and efficiency to both the standard HTTP server and the HTTPS server, complete the procedure in this section.

              SUMMARY STEPS

                1.    enable

                2.    configure terminal

                3.    ip http path path-name

                4.    ip http access-class access-list-number

                5.    ip http max-connections value

                6.    ip http timeout-policy idle seconds life seconds requests value


              DETAILED STEPS
                 Command or ActionPurpose
                Step 1 enable


                Example:
                Router> enable
                 

                Enables privileged EXEC mode.

                • Enter your password if prompted.
                 
                Step 2 configure terminal


                Example:
                Router# configure terminal 
                 

                Enters global configuration mode.

                 
                Step 3 ip http path path-name


                Example:
                Router(config)# ip http path slot1:
                 

                (Optional) Sets the base HTTP path for HTML files.

                • The base path is used to specify the location of the HTTP server files (HTML files) on the local system. Generally, the HTML files are located in system flash memory.
                 
                Step 4 ip http access-class access-list-number


                Example:
                Router(config)# ip http access-class 20
                 

                (Optional) Specifies the access list that should be used to allow access to the HTTP server.

                 
                Step 5 ip http max-connections value


                Example:
                Router(config)# ip http max-connections 10
                 

                (Optional) Sets the maximum number of concurrent connections to the HTTP server that will be allowed. The default value is 5.

                 
                Step 6 ip http timeout-policy idle seconds life seconds requests value


                Example:
                Router(config)# ip http timeout-policy idle 30 life 120 requests 100 
                 

                (Optional) Sets the characteristics that determine how long a connection to the HTTP server should remain open. The characteristics are:

                • idle --The maximum number of seconds the connection will be kept open if no data is received or response data cannot be sent out on the connection. Note that a new value may not take effect on any already existing connections. If the server is too busy or the limit on the life time or the number of requests is reached, the connection may be closed sooner. The default value is 180 seconds (3 minutes).
                • life --The maximum number of seconds the connection will be kept open, from the time the connection is established. Note that the new value may not take effect on any already existing connections. If the server is too busy or the limit on the idle time or the number of requests is reached, it may close the connection sooner. Also, because the server will not close the connection while actively processing a request, the connection may remain open longer than the specified life time if processing is occurring when the life maximum is reached. In this case, the connection will be closed when processing finishes. The default value is 180 seconds (3 minutes). The maximum value is 86,400 seconds (24 hours).
                • requests --The maximum limit on the number of requests processed on a persistent connection before it is closed. Note that the new value may not take effect on any already existing connections. If the server is too busy or the limit on the idle time or the life time is reached, the connection may be closed before the maximum number of requests are processed. The default value is 1. The maximum value is 86,400.
                 

                Configuring the HTTPS Client with SSL 3.0

                To configure the HTTPS client with SSL 3.0, complete the procedure in this section.

                Before You Begin

                The standard HTTP client and the secure HTTP client are always enabled.

                A certificate authority is required for secure HTTP client certification; the following steps assume that you have previously declared a CA trustpoint on the routing device. If a CA trustpoint is not configured, and the remote HTTPS server requires client authentication, connections to the secure HTTP client will fail.

                SUMMARY STEPS

                  1.    enable

                  2.    configure terminal

                  3.    ip http client secure-trustpoint trustpoint-name

                  4.    ip http client secure-ciphersuite [3des-ede-cbc-sha] [rc4-128-sha] [rc4-128-md5] [des-cbc-sha]

                  5.    end

                  6.    show ip http client secure status


                DETAILED STEPS
                   Command or ActionPurpose
                  Step 1 enable


                  Example:
                  Router> enable
                   

                  Enables privileged EXEC mode.

                  • Enter your password if prompted.
                   
                  Step 2 configure terminal


                  Example:
                  Router# configure terminal 
                   

                  Enters global configuration mode.

                   
                  Step 3 ip http client secure-trustpoint trustpoint-name


                  Example:
                  Router(config)# ip http client secure-trustpoint trustpoint01
                   

                  (Optional) Specifies the CA trustpoint that should be used if the remote HTTP server requests client authentication.

                  • Use of this command assumes you have already declared a CA trustpoint using the crypto ca trustpoint command and associated submode commands.
                  • Use the same trustpoint name that you used in the associated crypto ca trustpoint command.
                  • This command is optional if client authentication is not needed, or if a primary trustpoint has been configured. If the ip http client secure-trustpoint command is not used, the router will use the primary trustpoint, as specified by the primaryCA trustpoint configuration mode command.
                   
                  Step 4 ip http client secure-ciphersuite [3des-ede-cbc-sha] [rc4-128-sha] [rc4-128-md5] [des-cbc-sha]


                  Example:
                  Router(config)# ip http client secure-ciphersuite rc4-128-sha rc4-128-md5 
                   

                  (Optional) Specifies the CipherSuites (encryption algorithms) that should be used for encryption over the HTTPS connection.

                  • This command allows you to restrict the list of CipherSuites that the client offers when connecting to a secure HTTP server. For example, you may want to allow only the most secure CipherSuites to be used.
                  • Unless you have a reason to specify the CipherSuites that should be used, or you are unfamiliar with the details of these CipherSuites, you should leave this command unconfigured and let the server and client negotiate the CipherSuite that they both support (this is the default).
                   
                  Step 5 end


                  Example:
                  Router(config)# end
                   

                  Ends the current configuration session and returns to privileged EXEC mode.

                   
                  Step 6 show ip http client secure status


                  Example:
                  Router# show ip http client secure status
                   

                  Displays the status of the HTTP secure server configuration.

                   

                  Configuration Examples for the HTTPS--HTTP Server and Client with SSL 3.0 feature

                  The following example shows a configuration session in which the secure HTTP server is enabled, the port for the secure HTTP server is configured as 1025, and the remote CA trustpoint server “CA-trust-local” is used for certification.

                  Router# show ip http server status
                   
                  HTTP server status: Disabled
                  HTTP server port: 80
                  HTTP server authentication method: enable
                  HTTP server access class: 0
                  HTTP server base path: 
                  Maximum number of concurrent server connections allowed: 5
                  Server idle time-out: 600 seconds
                  Server life time-out: 600 seconds
                  Maximum number of requests allowed on a connection: 1
                  HTTP secure server capability: Present
                  HTTP secure server status: Disabled
                  HTTP secure server port: 443
                  HTTP secure server ciphersuite: 3des-ede-cbc-sha des-cbc-sha rc4-128-md5 rc4-12a
                  HTTP secure server client authentication: Disabled
                  HTTP secure server trustpoint: 
                  Router# configure terminal
                   
                  Enter configuration commands, one per line.  End with CNTL/Z.
                  Router(config)# ip http secure-server
                   
                  Router(config)# ip http client secure-trustpoint CA-trust-local
                   
                  Router(config)# ip http secure-port 1024
                   
                  Invalid secure port value.
                  Router(config)# ip http secure-port 1025
                   
                  Router(config)# ip http secure-ciphersuite rc4-128-sha rc4-128-md5 
                  Router(config)# end
                  
                  Router# show ip http server secure status
                  HTTP secure server status: Enabled
                  HTTP secure server port: 1025
                  HTTP secure server ciphersuite: rc4-128-md5 rc4-128-sha
                  HTTP secure server client authentication: Disabled
                  HTTP secure server trustpoint: CA-trust-local
                  

                  In the following example, the CA trustpoint CA-trust-local is specified, and the HTTPS client is configured to use this trustpoint for client authentication requests:

                  Router# config terminal
                  Enter configuration commands, one per line.  End with CNTL/Z.
                  Router(config)# crypto ca trustpoint CA-trust-local
                   
                  Router(ca-trustpoint)# enrollment url http://example.com
                   
                  Router(ca-trustpoint)# crl query ldap://example.com
                   
                  Router(ca-trustpoint)# primary
                   
                  Router(ca-trustpoint)# exit
                   
                  Router(config)# ip http client secure-trustpoint CA-trust-local
                   
                  Router(config)# end
                   
                  Router# copy running-config startup-config
                   

                  Additional References

                  The following sections provide references related to the HTTPS--HTTP Server and Client with SSL 3.0 feature.

                  Related Documents

                  Related Topic

                  Document Title

                  SSL 3.0

                  The SSL Protocol Version 3.0

                  This document is available from various sources online.

                  Standard Cisco Web Client

                  HTTP 1.1 Web Client

                  Standard Cisco Web Server

                  HTTP 1.1 Web Server

                  Certification Authority Interoperability

                  • Configuring Certification Authority Interoperability
                  • Certificate Autoenrollment
                  • Certificate Enrollment Enhancements
                  • Trustpoint CLI
                  • Source Interface Selection for Outgoing Traffic with Certificate Authority

                  Standards

                  Standard

                  Title

                  No new or modified standards are supported by this feature.

                  --

                  Related MIBs

                  MIBs

                  MIBs Link

                  • No new or modified MIBs are supported by this feature and support for existing MIBs has not been modified by this feature.

                  To locate and download MIBs for selected platforms, Cisco IOS XE releases, and feature sets, use Cisco MIB Locator found at the following URL:

                  http:/​/​www.cisco.com/​go/​mibs

                  Related RFCs

                  RFCs

                  Description

                  RFC 2616

                  Cisco’s implementation of HTTP is based on RFC 2616: Hypertext Transfer Protocol -- HTTP/1.1 .

                  Technical Assistance

                  Description

                  Link

                  The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies.

                  To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds.

                  Access to most tools on the Cisco Support website requires a Cisco.com user ID and password.

                  http:/​/​www.cisco.com/​techsupport

                  Feature Information for HTTPS--HTTP Server and Client with SSL 3.0

                  The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

                  Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

                  Table 1 Feature Information for HTTPS--HTTP Server and Client with SSL 3.0

                  Feature Name

                  Releases

                  Feature Information

                  HTTPS--HTTP Server and Client with SSL 3.0

                  Cisco IOS XE Release 2.1

                  This feature provides Secure Socket Layer (SSL) version 3.0 support for the HTTP 1.1 server and HTTP 1.1 client within Cisco IOS XE software. SSL provides server authentication, encryption, and message integrity to allow secure HTTP communications. SSL also provides HTTP client authentication.

                  This feature is supported only in Cisco software images that support SSL. Specifically, SSL is supported in “IPSec 56” and “IPSec 3DES” images (contains “k8” or “k9” in the image name).

                  The following commands are introduced or modified in the feature or features documented in this module.

                  • debug ip http ssl error
                  • ip http client secure-ciphersuite
                  • ip http client secure-trustpoint
                  • ip http secure-ciphersuite
                  • ip http secure-client-auth
                  • ip http secure-port
                  • ip http secure-server
                  • ip http secure-trustpoint
                  • show ip http client secure status
                  • show ip http server secure status

                  Glossary

                  RSA--RSA is a widely used Internet encryption and authentication system that uses public and private keys for encryption and decryption. The RSA algorithm was invented in 1978 by Ron Rivest, Adi Shamir, and Leonard Adleman. The abbreviation RSA comes from the first letter of the last names of the three original developers. The RSA algorithm is included in many applications, such as the web browsers from Microsoft and Netscape. The RSA encryption system is owned by RSA Security.

                  SHA --The Secure Hash Algorithm. SHA was developed by NIST and is specified in the Secure Hash Standard (SHS, FIPS 180). Often used as an alternative to Digest 5 algorithm.

                  signatures, digital--In the context of SSL, “signing” means to encrypt with a private key. In digital signing, one-way hash functions are used as input for a signing algorithm. In RSA signing, a 36-byte structure of two hashes (one SHA and one MD5) is signed (encrypted with the private key).

                  SSL 3.0--Secure Socket Layer version 3.0. SSL is a security protocol that provides communications privacy over the Internet. The protocol allows client and server applications to communicate in a way that is designed to prevent eavesdropping, tampering, or message forgery. SSL uses a program layer located between the Internet’s HTTP and TCP layers. SSL is included as part of most web server products and as part of most Internet browsers.