0x00 背景

Elasticsearch是一個基于Lucene構建的開源,分布式,RESTful搜索引擎，大量使用于各種場景，隨著不斷的發展，不可避免的會產生安全問題，一些危害比較大的漏洞比如CVE-2015-3337、CVE-2015-5531。面對這些漏洞（包括0day）的威脅，以及多業務使用使用同一套es集群的情況，使用一套認證授權系統就顯得尤為必要。
經過es1代到2代產品的過度，目前主流的方案就只有官方的shield以及開源search-guard，然而我廠比較扣。

0x01 search-guard

search-guard 更新到2.x后跟 shield 配置上很相似，相比1.x的版本邏輯上更加松散。

searchguard 優點有：

節點之間通過 SSL/TLS 傳輸
支持 JDK SSL 和 Open SSL
支持熱載入，不需要重啟服務
支持 kibana4 及 logstash 的配置
可以控制不同的用戶訪問不同的權限
配置簡單

0x02 安裝

安裝search-guard-ssl

#!bash
sudo bin/plugin install -b com.floragunn/search-guard-ssl/2.3.3.11
復制代碼

安裝search-guard-2

#!bash
sudo bin/plugin install -b com.floragunn/search-guard-2/2.3.3.0-rc1
復制代碼

0x03 證書

根據自身情況修改官方腳本生成admin證書、node證書、根證書，將 node 證書和根證書放在 elasticsearch 配置文件目錄下，同時將admin證書和根證書放到search-guard 配置文件目錄下

tips：證書需要統一生成

0x04 配置 elasticsearch 支持 ssl

elasticsearch.yml增加以下配置：

#!bash
#############################################################################################
#                                       SEARCH GUARD                                        #
#                                       Configuration                                       #
#############################################################################################
# Add the following properties to your standard elasticsearch.yml
# (alongside with the SG SSL settings)
# This settings must always be the same on all nodes in the cluster# This defines the DNs (distinguished names) of certificates
# to which admin privileges should be assigned
security.manager.enabled: false
searchguard.authcz.admin_dn:- "CN=kirk,OU=client,O=client,l=tEst, C=De"
# kirk是administrator，可以自行修改
# This is optional
# Only needed when impersonation is used
# Allow DNs (distinguished names) to impersonate as other users
#searchguard.authcz.impersonation_dn:
#  "CN=spock,OU=client,O=client,L=Test,C=DE":
#    - worf
#  "cn=webuser,ou=IT,ou=IT,dc=company,dc=com":
#    - user2
#    - user1# Auditlog configuration:searchguard.audit.type: internal_elasticsearch
#searchguard.audit.type: external_elasticsearch
#searchguard.audit.config.http_endpoints: ['localhost:9200','localhost:9201','localhost:9202']"
#searchguard.audit.config.index: auditlog # make sure you secure this index properly
#searchguard.audit.config.type: auditlog
#searchguard.audit.config.username: auditloguser
#searchguard.audit.config.password: auditlogpassword
#searchguard.audit.config.enable_ssl: false
#searchguard.audit.config.verify_hostnames: false
#searchguard.audit.config.enable_ssl_client_auth: false# If Kerberos authentication should be used you have to configure this:# The absolute path or relative path to config/ directory
# to krb5.conf file
#searchguard.kerberos.krb5_filepath: '/etc/krb5.conf'# The absolute path or relative path to config/ directory
# to the keytab where the acceptor_principal credentials are stored.
#searchguard.kerberos.acceptor_keytab_filepath: 'eskeytab.tab'#############################################################################################
#                                     SEARCH GUARD SSL                                      #
#                                       Configuration                                       #
##########################################################################################################################################################################################
# Transport layer SSL                                                                       #
#                                                                                           #
#############################################################################################
# Enable or disable node-to-node ssl encryption (default: true)
searchguard.ssl.transport.enabled: true
# JKS or PKCS12 (default: JKS)
searchguard.ssl.transport.keystore_type: JKS
# Relative path to the keystore file (mandatory, this stores the server certificates), must be placed under the config/ dir
searchguard.ssl.transport.keystore_filepath: node-1-keystore.jks
# 當前節點的證書，根據節點名字生成
# Alias name (default: first alias which could be found)
#searchguard.ssl.transport.keystore_alias: my_alias
# Keystore password (default: changeit)
#searchguard.ssl.transport.keystore_password: changeit# JKS or PKCS12 (default: JKS)
searchguard.ssl.transport.truststore_type: JKS
# Relative path to the truststore file (mandatory, this stores the client/root certificates), must be placed under the config/ dir
searchguard.ssl.transport.truststore_filepath: truststore.jks
# Alias name (default: first alias which could be found)
#searchguard.ssl.transport.truststore_alias: my_alias
# Truststore password (default: changeit)
searchguard.ssl.transport.truststore_password: changeit
# Enforce hostname verification (default: true)
searchguard.ssl.transport.enforce_hostname_verification: true
# 如果沒有證書服務器，需要設置為false，否則無法加入集群
# If hostname verification specify if hostname should be resolved (default: true)
searchguard.ssl.transport.resolve_hostname: true
# Use native Open SSL instead of JDK SSL if available (default: true)
searchguard.ssl.transport.enable_openssl_if_available: false# Enabled SSL cipher suites for transport protocol (only Java format is supported)
# WARNING: Expert setting, do only use if you know what you are doing
# If you set wrong values here this this could be a security risk
#searchguard.ssl.transport.enabled_ciphers:
#  - "TLS_DHE_RSA_WITH_AES_256_CBC_SHA"
#  - "TLS_DHE_DSS_WITH_AES_128_CBC_SHA256"# Enabled SSL protocols for transport protocol (only Java format is supported)
# WARNING: Expert setting, do only use if you know what you are doing
# If you set wrong values here this this could be a security risk  
#searchguard.ssl.transport.enabled_protocols:
#  - "TLSv1.2"#############################################################################################
# HTTP/REST layer SSL                                                                       #
#                                                                                           #
#############################################################################################
# Enable or disable rest layer security - https, (default: false)
#searchguard.ssl.http.enabled: true
# JKS or PKCS12 (default: JKS)
#searchguard.ssl.http.keystore_type: PKCS12
# Relative path to the keystore file (this stores the server certificates), must be placed under the config/ dir
#searchguard.ssl.http.keystore_filepath: keystore_https_node1.jks
# Alias name (default: first alias which could be found)
#searchguard.ssl.http.keystore_alias: my_alias
# Keystore password (default: changeit)
#searchguard.ssl.http.keystore_password: changeit
# Do the clients (typically the browser or the proxy) have to authenticate themself to the http server, default is OPTIONAL
# To enforce authentication use REQUIRE, to completely disable client certificates use NONE
#searchguard.ssl.http.clientauth_mode: REQUIRE
# JKS or PKCS12 (default: JKS)
#searchguard.ssl.http.truststore_type: PKCS12
# Relative path to the truststore file (this stores the client certificates), must be placed under the config/ dir
#searchguard.ssl.http.truststore_filepath: truststore_https.jks
# Alias name (default: first alias which could be found)
#searchguard.ssl.http.truststore_alias: my_alias
# Truststore password (default: changeit)
#searchguard.ssl.http.truststore_password: changeit
# Use native Open SSL instead of JDK SSL if available (default: true)
#searchguard.ssl.http.enable_openssl_if_available: false# Enabled SSL cipher suites for http protocol (only Java format is supported)
# WARNING: Expert setting, do only use if you know what you are doing
# If you set wrong values here this this could be a security risk
#searchguard.ssl.http.enabled_ciphers:
#  - "TLS_DHE_RSA_WITH_AES_256_CBC_SHA"
#  - "TLS_DHE_DSS_WITH_AES_128_CBC_SHA256"# Enabled SSL protocols for http protocol (only Java format is supported)
# WARNING: Expert setting, do only use if you know what you are doing
# If you set wrong values here this this could be a security risk  
#searchguard.ssl.http.enabled_protocols:
#  - “TLSv1.2"
復制代碼

重啟 elasticsearch

注意：任何修改elasticsearch.yml的操作都需要重啟elasticsearch才能生效

配置文件介紹

searchguard 主要有5個配置文件在 plugins/search-guard-2/sgconfig 下：

sg_config.yml:

主配置文件不需要做改動

sg_internal_users.yml:

本地用戶文件，定義用戶密碼以及對應的權限。例如：對于 ELK 我們需要一個 kibana 登錄用戶和一個 logstash 用戶：

#!bash
kibana4:hash: $2a$12$xZOcnwYPYQ3zIadnlQIJ0eNhX1ngwMkTN.oMwkKxoGvDVPn4/6XtO#password is: kirkroles:- kibana4
logstash:hash: $2a$12$xZOcnwYPYQ3zIadnlQIJ0eNhX1ngwMkTN.oMwkKxoGvDVPn4/6XtOroles:- logstash
復制代碼

密碼可用plugins/search-guard-2/tools/hash.sh生成

sg_roles.yml:

權限配置文件，這里提供 kibana4 和 logstash 的權限樣例

#!bash
#<sg_role_name>:
#  cluster:
#    - '<permission>'
#  indices:
#    '<indexname or alias>':
#      '<type>':  
#        - '<permission>'
#      _dls_: '<querydsl query>'
#      _fls_:
#        - '<field>'
#        - '<field>'
sg_kibana4:cluster:- cluster:monitor/nodes/info- cluster:monitor/healthindices:'*':'*':- indices:admin/mappings/fields/get- indices:admin/validate/query- indices:data/read/search- indices:data/read/msearch- indices:admin/get- indices:data/read/field_stats'?kibana':'*':- indices:admin/exists- indices:admin/mapping/put- indices:admin/mappings/fields/get- indices:admin/refresh- indices:admin/validate/query- indices:data/read/get
sg_logstash:cluster:- indices:admin/template/get- indices:admin/template/putindices:'logstash-*':'*':- WRITE- indices:data/write/bulk- indices:data/write/delete- indices:data/write/update- indices:data/read/search- indices:data/read/scroll- CREATE_INDEX
復制代碼

sg_roles_mapping.yml:

定義用戶的映射關系，添加 kibana 及 logstash 用戶對應的映射：

#!bash
sg_logstash:users:- logstash
sg_kibana4:backendroles:- kibanausers:- kibana4
復制代碼

sg_action_groups.yml:

定義權限

加載配置并啟用

#!bash
sh plugins/search-guard-2/tools/sgadmin.sh -cn 集群名稱（默認為elasticsearch，修改名稱必須添加此參數） -h 127.0.0.1 -cd plugins/search-guard-2/sgconfig -ks plugins/search-guard-2/sgconfig/kirk-keystore.jks -kspass kspass -ts plugins/search-guard-2/sgconfig/truststore.jks  -tspass tspass -nhnv
復制代碼

如修改了searchguard，則需要重新加載配置執行

注意：search-guard配置的相關改動不需要重啟elasticsearch，相關的配置實際上存儲在searchguard 的indice下了

至此大家就可以安全的使用elasticsearch

關于ldap以及https的配置將在下一篇給出