\u9632\u706b\u7246\u7684\u57fa\u672c\u6982\u5ff5\uff1a\u907f\u514d\u5165\u4fb5\u8005\u9032\u5165,\u9632\u6b62\u6a5f\u5bc6\u8cc7\u6599\u5916\u6d29
\u8a2d\u8a08\u76ee\u6a19\uff1a
\u6240\u6709\u7531\u5167\u5230\u5916\u6216\u7531\u5916\u5230\u5167\u7684\u6d41\u91cf\u9700\u7d93\u9632\u706b\u7246
\u7d93\u904e\u6388\u6b0a\u624d\u53ef\u901a\u904e
\u5c0d\u5165\u4fb5\u5177\u6709\u514d\u75ab\u529b
ps:70%\u7684\u653b\u64ca\u662f\u4f86\u81ea\u9632\u706b\u7246\u5167\u90e8<\/p>\n\n\n\n
\u9632\u706b\u7246\u4e00\u822c\u67b6\u69cb:\u5916\u90e8\u5c01\u5305\u904e\u6ffe\u8def\u7531\u5668+\u61c9\u7528\u9598\u9053\u5668+\u5167\u90e8\u5c01\u5305\u904e\u6ffe\u8def\u7531\u5668
\u9632\u706b\u7246\u4e3b\u8981\u6280\u8853:\u670d\u52d9\u76e3\u63a7,\u65b9\u5411\u76e3\u63a7,\u4f7f\u7528\u8005\u76e3\u63a7,\u884c\u70ba\u76e3\u63a7
\u9632\u706b\u7246\u4e3b\u8981\u7a2e\u985e:\u5c01\u5305\u904e\u6ffe,\u61c9\u7528\u7a0b\u5f0f\u9598\u9053\u5668,\u96fb\u8def\u5c64\u9598\u9053\u5668,\u72c0\u614b\u8a18\u61b6\u9ad4\u5c01\u5305\u6aa2\u67e5\u5f15\u64ca
\u984d\u5916\u529f\u80fd\uff1anat,vpn,\u7a3d\u6838\u8a18\u9304,\u71b1\u5099\u63f4hotstandby,\u8a8d\u8b49,Traffic Shaping(\u983b\u5bec\u7ba1\u7406)<\/p>\n\n\n\n
…………………………………………………………………………<\/p>\n\n\n\n
firewall ……………….<\/p>\n\n\n\n types of firewalls:<\/strong> …<\/p>\n\n\n\n packet filitering(\u5c01\u5305\u904e\u6ffe)<\/strong> \u5c01\u5305\u904e\u6ffe\u7b56\u7565\u6709: \u5c01\u5305\u904e\u6ffe\u5668\u53ef\u53cd\u5236 ps: … <\/p>\n\n\n\n SPI(stateful packet-inspection,\u72c0\u614b\u8a18\u61b6\u5f0f\u5c01\u5305\u6aa2\u67e5)<\/strong> ps: …..<\/p>\n\n\n\n circuit-level gateways(\u96fb\u8def\u5f0f\u9598\u9053)<\/strong> ps: …..<\/p>\n\n\n\n application gateways(\u61c9\u7528\u5c64\u9598\u9053)<\/strong> …..<\/p>\n\n\n\n stateful multilayer inspection(\u72c0\u614b\u591a\u968e\u5c64\u6aa2\u67e5)<\/strong> DMZ(demilitarized zone,\u7db2\u969b\u7db2\u8def\u5b89\u5168\u5340) \u4f48\u7f72\u67b6\u69cb firewall identification<\/strong> breaching firewalls:<\/strong> \u5f71\u97ff firewall\u4f5c\u6cd5<\/strong> ps \u7a81\u7834firewall tool …<\/p>\n\n\n\n firewall,ids test tool \u9632\u706b\u7246\u7684\u57fa\u672c\u6982\u5ff5\uff1a\u907f\u514d\u5165\u4fb5\u8005\u9032\u5165,\u9632\u6b62\u6a5f\u5bc6\u8cc7\u6599\u5916\u6d29\u8a2d\u8a08\u76ee\u6a19\uff1a …<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"fifu_image_url":"","fifu_image_alt":"","_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[10],"tags":[],"class_list":["post-437","post","type-post","status-publish","format-standard","hentry","category-securitysloution"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/posts\/437","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/comments?post=437"}],"version-history":[{"count":0,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/posts\/437\/revisions"}],"wp:attachment":[{"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/media?parent=437"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/categories?post=437"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/systw.net\/note\/wp-json\/wp\/v2\/tags?post=437"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
hardward firewall<\/strong>
ex:
Netscreen
Cisco Pix Firewall
software firewall<\/strong>
ex:
ipfw\/natd \u9632\u8b77bsd
netfilter\/iptables \u9632\u8b77linux
wf\/ics \u9632\u8b77windows<\/p>\n\n\n\n
packet filters
SPI
circuit level gateways
application level gateways
stateful multilayer inspection firewalls
\u6bd4\u8f03\u5982\u4e0b
packet filitering <\/strong>
\u3000\u53ef\u4f9dip,protocol,port\u904e\u6ffe\u8cc7\u6599
\u3000\u7121\u6cd5\u5224\u65b7\u9023\u7dda\u662f\u5426\u5408\u6cd5
\u3000\u7121\u6cd5\u5c0d\u61c9\u7528\u5c64\u7684\u8cc7\u6599\u505a\u8655\u7406
SPI <\/strong>
\u3000\u5305\u542bpacket filter\u529f\u80fd
\u3000\u53ef\u7528\u9023\u7dda\u72c0\u614b\u8868\uff0c\u5224\u65b7\u8a72\u5224\u65b7\u9023\u7dda\u662f\u5426\u5408\u6cd5
\u3000\u7121\u6cd5\u5c0d\u61c9\u7528\u5c64\u7684\u8cc7\u6599\u505a\u8655\u7406
application gateways<\/strong>
\u3000\u5305\u542bSPI\u529f\u80fd
\u3000\u53ef\u770b\u5230\u6bcf\u500b\u5c01\u5305\u5167\u5bb9\uff0c\u56e0\u6b64\u53ef\u5c0d\u61c9\u7528\u5c64\u7684\u8cc7\u6599\u505a\u8655\u7406<\/p>\n\n\n\n
\u904b\u4f5c\u5728network layer
\u5224\u65b7\u4f9d\u64da\uff1a\u4f86\u6e90\u8207\u76ee\u5730\u7aefip,\u4f86\u6e90\u548c\u76ee\u5730port,protocol(TCP,UDP,ICMP),\u4ecb\u9762
\u512a\u9ede:low cost,\u5c0d\u7db2\u8def\u6548\u80fd\u5f71\u97ff\u5c0f,most routers support
\u7f3a\u9ede:\u76f8\u8f03\u5176\u4ed6\u985e\u578bfirewall\u8f03\u4e0d\u5b89\u5168,\u7121\u6cd5\u6aa2\u8996\u4e0a\u5c64\u8cc7\u6599,\u5141\u8a31\u548c\u4e0d\u53ef\u4fe1\u4efb\u4e3b\u6a5f\u76f4\u63a5\u9023\u7dda,\u64f4\u5145\u6027\u5dee,\u53ef\u80fd\u906d\u5230\u5047\u5192\u653b\u64ca,\u6703\u5141\u8a31\u6240\u6709ack\u5c01\u5305\u901a\u904e<\/p>\n\n\n\n
\u958b\u653e\u578b\u7db2\u8def\uff1a\u53ea\u64cb\u6389\u5e7e\u7a2e\u4e0d\u8981\u7684\u5c01\u5305
\u5c01\u9589\u578b\u7db2\u8def\uff1a\u53ea\u8b93\u5e7e\u7a2e\u4e8b\u5148\u6838\u51c6\u7684\u5c01\u5305\u904e\u901a<\/p>\n\n\n\n
a.ip\u4f4d\u5740\u507d\u88dd\uff1a\u5c01\u5305\u4f86\u6e90ip\u507d\u88dd\u70ba\u5167\u90e8\u4e3b\u6a5fip\u6642,\u4e1f\u68c4\u5c01\u5305
b.\u4f86\u6e90\u8def\u5f91\u653b\u64ca\uff1a
c.\u7d30\u5fae\u5340\u6bb5\u653b\u64ca\u6cd5\uff1a\u5207\u5272ip\u5c01\u5305\u9019\u500b\u9078\u64c7\u6027\u6b04\u4f4d,\u7522\u751f\u5fae\u5c0f\u5340\u6bb5,\u4e26\u5c07tcp\u6a19\u982d\u7f6e\u5165\u53e6\u4e00\u5c01\u5305\u5340\u6bb5,\u4ee5\u7e5e\u904e\u6aa2\u67e5
\u985e\u4f3cdos\u7684TearDrop\u653b\u64ca,\u82e5\u504f\u79fb\u91cf\u70ba1\u5373\u4e1f\u68c4<\/p>\n\n\n\n
\u7d041983\u5e74\u65bc\u8def\u7531\u5668\u540c\u6642\u51fa\u73fe<\/p>\n\n\n\n
\u53c8\u7a31dynamic packet filter(\u52d5\u614b\u5c01\u5305\u904e\u6ffe)
\u5224\u65b7\u4f9d\u64da:connection state table(\u9023\u7dda\u72c0\u614b\u8868)
\u6839\u64da\u4e00\u7d44\u548c\u5c01\u5305\u904e\u6ffe\u5668\u985e\u4f3c\u7684\u898f\u5247\u7d44\u6c7a\u5b9a\u5c01\u5305\u7684\u901a\u884c
\u6703\u8ffd\u8e64\u6bcf\u4e00\u689d\u9023\u7dda\u7684\u72c0\u614b,\u4f9d\u9023\u7dda\u9700\u6c42\u52d5\u614b\u958b\u555f\u6216\u95dc\u9589\u9023\u63a5\u57e0
\u53ea\u6709\u7576\u9032\u5165\u7684\u5c01\u5305\u8207\u9023\u7dda\u72c0\u614b\u8868\u7684\u4efb\u4e00\u8cc7\u6599\u76f8\u7b26\u6642,\u624d\u5141\u8a31\u9032\u5165\u7684\u6d41\u91cf\u4f7f\u7528
ex:\u4f9d\u64daSYN,ACK,\u5e8f\u865f,\u5176\u4ed6TCP\u6a19\u982d\u6240\u542b\u8cc7\u6599
\u512a\u9ede\uff1a
\u3000\u4f9d\u64da\u9023\u7dda\u72c0\u614b\u8868(\u542b\u53ef\u9023port\u53caip)
\u3000\u53ef\u6709\u6548\u9632\u5835\u5047\u5192\u5df1\u5b58\u5728\u9023\u7dda\u5c01\u5305(\u56e0\u5047\u5192\u9023\u7dda\u4e0d\u6703\u5728\u8a18\u9304\u5728\u8868\u4e2d)
\u3000\u4e0d\u6703\u96a8\u4fbf\u8b93ack\u5c01\u5305\u901a\u904e,\u53ef\u5206\u8fa6\u90a3\u4e9bACK\u5c01\u5305\u662f\u771f\u7684\u6216\u5047\u7684
\u3000\u53ef\u91dd\u5c0d\u7279\u5b9a\u5c01\u5305\u985e\u578b\u6df1\u5165\u6aa2\u67e5\u5176\u8cc7\u6599
\u7f3a\u9ede\uff1a
\u3000\u5141\u8a31\u4e0d\u53ef\u4fe1\u4efb\u4e3b\u6a5f\u8207\u53ef\u4fe1\u4efb\u4e3b\u6a5f\u9593\u76f4\u63a5\u9023\u7dda
<\/p>\n\n\n\n
\u52d5\u614b\u5c01\u5305\u904e\u6ffe\u70baBob Braden\u65bc1992\u5e74\u6240\u7814\u767c,\u4e4b\u5f8c\u53c8\u6f14\u8b8a\u70baSPI <\/p>\n\n\n\n
\u904b\u4f5c\u5728session layer
\u76e3\u63a7tcp handshaking\u5224\u65b7session\u662f\u5426\u5408\u6cd5
\u904b\u4f5c\u65b9\u5f0f\uff1a
1\u5148\u963b\u9694\u7aef\u5c0d\u7aef\u7684TCP\u9023\u63a5,\u4f7f\u7528\u8005\u5c0d\u5916\u90e8\u4e3b\u6a5f\u7684\u9023\u7dda\u5747\u900f\u904eCircuit Level Gateway\u8f49\u7f6e
2\u9023\u7dda\u5df1\u5efa\u7acb\u5373\u53ef\u4e0d\u9700\u901a\u904e\u6aa2\u67e5(\u4e0d\u904e\u6ffe\u500b\u5225packet)\u5c31\u5b89\u5168\u901a\u904e
\u4e3b\u8981\u662f\u4ee5\u6aa2\u67e5\u662f\u5426\u53ef\u5728\u5169\u4e3b\u6a5f\u9593\u5efa\u7acb\u9023\u7dda\u4f86\u9054\u6210\u5176\u5b89\u5168\u8981\u6c42
ex:SOCKS\u4ee3\u7406\u5668<\/p>\n\n\n\n
\u8c9d\u723e\u5be6\u9a57\u5ba4\u7684Dave Presotto\u548cHoward Trickey\u63a8\u51fa\u7684\u7b2c\u4e8c\u4ee3\u9632\u706b\u7246,\u4e5f\u662f\u61c9\u7528\u5c64\u9598\u9053\u7684\u524d\u8eab<\/p>\n\n\n\n
\u904b\u4f5c\u5728application layer,\u8ca0\u8cac\u61c9\u7528\u5c64\u7d1a\u8a0a\u606f\u8f49\u9001, \u4f9dOSI\u6bcf\u4e00\u5c64\u5c01\u5305\u8cc7\u8a0a\u505a\u5b58\u53d6\u63a7\u5236\u6c7a\u7b56
\u53ef\u4ee5\u662fbastion host(\u4fdd\u58d8\u4e3b\u6a5f),proxy gateway(\u4ee3\u7406\u9598\u9053\u5668),proxy server(\u4ee3\u7406\u4f3a\u670d\u5668)
\u5e38\u505a\u96fb\u5b50\u90f5\u4ef6,FTP,telnet,HTTP\u7b49\u61c9\u7528\u7a0b\u5f0f\u4e2d\u4ecb
\u53ef\u6aa2\u8996\u6bcf\u500b\u50b3\u5165\u6216\u5916\u9001\u8a0a\u606f,\u4e26\u91dd\u5c0d\u8868\u982d\u6b04\u4f4d,\u8a0a\u606f\u9577\u5ea6,\u5167\u5bb9\u4f86\u6c7a\u5b9a\u4e1f\u68c4\u6216\u50b3\u8f38
\u80fd\u57f7\u884c\u984d\u5916\u8eab\u4efd\u9a57\u8b49\u8207\u8cc7\u8a0a\u8a18\u9304,\u5177\u5099\u8db3\u5920\u80fd\u529b\u53ef\u57f7\u884c\u8cc7\u6599\u8f49\u63db,\u4e5f\u53ef\u79fb\u9664\u7db2\u9801\u4e2d\u7684activex\u6216 javascripts
\u53ef\u5efa\u7acb\u865b\u64ec\u9023\u7dda\u81ea\u52d5\u5c07\u5167\u90e8\u7528\u6236\u7aef\u96fb\u8166\u7684IP\u4f4d\u5740\u96b1\u85cf\u8d77\u4f86\uff0c\u4e0d\u8b93Interne\u7db2\u969b\u7db2\u8def\u7684\u4eba\u77e5\u66c9\u5167\u90e8\u7db2\u8def\u7684\u67b6\u69cb\u3002
\u512a\u9ede\uff1a\u9ad8\u5b89\u5168
\u7f3a\u9ede\uff1a\u9808\u984d\u5916\u8655\u7406\u6bcf\u500b\u9023\u7dda\u6548\u80fd\u5dee,\u7f3a\u4e4f\u900f\u901a\u6027(\u5b8c\u6210\u4f7f\u7528\u8005\u8981\u6c42),\u7121\u6cd5\u5728\u67d0\u4e9b\u670d\u52d9\u4e0a\u505a\u904b\u4f5c<\/p>\n\n\n\n
\u904b\u4f5c\u5728application,session,network layer
\u7f3a\u9ede:high cost<\/p>\n\n\n\n
…………………………………………………………………………………………………………………<\/p>\n\n\n\n
\u4e5f\u7a31\u70baperimeter network(\u9130\u754c\u7db2\u8def),\u6216routing network(\u9078\u5f91\u7db2\u8def)
\u901a\u5e38\u653e\u7f6e\u4e00\u4e9b\u4e0d\u542b\u6a5f\u5bc6\u8cc7\u8a0a\u7684\u516c\u7528\u4f3a\u670d\u5668\uff0c\u6bd4\u5982Web\u3001Mail\u3001FTP\u7b49
\u5916\u7db2\u7684\u8a2a\u554f\u8005\u53ef\u4ee5\u8a2a\u554fDMZ\u4e2d\u7684\u670d\u52d9\uff0c\u4f46\u4e0d\u80fd \u63a5\u89f8\u5230\u5167\u7db2\u4e2d\u7684\u516c\u53f8\u6a5f\u5bc6\u6216\u79c1\u4eba\u8cc7\u8a0a\u7b49
\u5373\u4f7fDMZ\u4e2d\u4f3a\u670d\u5668\u53d7\u5230\u7834\u58de\uff0c\u4e5f\u4e0d\u6703\u5c0d\u5167\u7db2\u4e2d\u7684\u6a5f\u5bc6\u8cc7\u8a0a\u9020\u6210\u5f71\u97ff
\u6240\u80fd\u9054\u5230\u7684\u6700\u9ad8\u5b89\u5168\u5883\u754c\u662f\u963b\u64cb\u4efb\u4f55\u5f9einternet\u76f4\u63a5\u5230 intranet\u7684\u8cc7\u6599,\u53ca\u5f9eintranet\u76f4\u63a5\u5230internet\u7684\u8cc7\u6599,\u96d9\u65b9\u90fd\u9700\u900f\u904edmz
\u53ef\u4ee5nat\u7576\u6210\u5167\u90e8\u8def\u7531\u5668,\u589e\u52a0\u99ed\u5ba2\u523a\u63a2\u5167\u90e8\u7db2 \u8def\u7684\u56f0\u96e3\u5ea6<\/p>\n\n\n\n
Dual-Homed Host(\u96d9\u4ecb\u9762\u4e3b\u6a5f):\u9032\u51fa\u7686\u900f\u904e\u4e00\u500b\u9632\u706b\u7246
screening router(\u55ae\u4e00\u8def\u7531\u5668\u9632\u706b\u7246): \u8def\u7531\u5668\u5167\u5efa\u5c01\u5305\u904e\u6ffe\u5668
Screened Host Gateway(\u5c4f\u969c\u5f0f\u9598\u9053\u5668\u9632\u706b\u7246):\u5916\u90e8\u5c01\u5305\u904e\u6ffe\u8def\u7531\u5668+\u61c9\u7528\u9598\u9053\u5668
\u6709\u5206single-homed bastion\u53cadual-homed bastion
Screened Subnet(\u5c4f\u969c\u5f0f\u5b50\u7db2\u9632\u706b\u7246):\u4e00\u822c\u67b6\u69cb,\u5916\u90e8\u5c01\u5305\u904e\u6ffe\u8def\u7531\u5668+\u61c9\u7528\u9598\u9053\u5668+\u5167\u90e8\u5c01\u5305\u904e\u6ffe\u8def\u7531\u5668
Belt & Suspenders(\u96d9\u5c4f\u969c\u5f0f\u5b50\u7db2\u9632\u706b\u7246):\u5c4f\u969c\u5f0f\u5b50\u7db2\u7684\u5ef6\u4f38,\u592a\u904e\u4fdd\u8b77\u6548\u7387\u4f4e<\/p>\n\n\n\n
…………………………………………………………………………………………………………<\/p>\n\n\n\n
port scanning:tool\u6709nmap,…\u7b49
firewalking:\u85c9\u7531 send\u4e00\u4e9bpakcet\u770b\u662f\u5426\u88ab\u963b\u64cb,tool\u6709firewalk
banner grabbing:tool\u6709telnet,…\u7b49<\/p>\n\n\n\n
insider
vulnerable services
vulnerable external server
hijacking connections<\/p>\n\n\n\n
\u4f7f\u7528tunnel,\u901a\u5e38\u7528\u4ee5\u4e0b\u65b9\u6cd5
bypassing a firewall using http tunnel:tool\u6709httptunnel
placing backdoors through firewall
hiding behind a covert channel:tool\u6709loki,ncovert
ack tunneling:\u5728ack\u88e1\u5305\u4e00\u4e9b\u8cc7\u6599
\u4f7f\u7528tor\u7a81\u7834firewall
\u4f7f\u7528socks \u5354\u5b9a\u7a81\u7834firewall,\u901a\u5e38\u4f7f\u7528tcp1080<\/p>\n\n\n\n
loki:\u904b\u7528icmp\u50b3\u6307\u4ee4\u7684backdoor,\u65b9\u5f0f\u662f\u5c07\u6307\u4ee4\u653e\u9032icmp\u7684payload\u88e1
ncovert:\u900f\u904e\u7279\u6b8a\u65b9\u6cd5\u96b1\u85cf\u50b3\u9001\u4e2d\u7684\u6a94\u6848\u548cip<\/p>\n\n\n\n
007shell
icmp shell
ack cmd
covert_tcp<\/p>\n\n\n\n
ftester(firewall tester)
traffic iq professional
nides(next-generation intrusion detection expert system),\u7b2c\u4e00\u500bperl\u5beb\u7684
secure host
snare
tcpopera:\u53ef\u4ee5\u5c0d\u8a2d\u5099\u6e2cpayload
firewall informer<\/p>\n","protected":false},"excerpt":{"rendered":"