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IP フラグメンテーション攻撃と DNS flag day 2020 / fragmentat...

koyane
December 19, 2020

IP フラグメンテーション攻撃と DNS flag day 2020 / fragmentation attack and flag day 2020

koyane

December 19, 2020
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  1. %/4GMBHEBZ ͸͡Ίʹ w ओʹ*1ϑϥάϝϯςʔγϣϯ͕Ҿ͖ى͜͢໰୊΁ͷରԠࡦͷ ద༻ w ೔࣌೥݄೔ w ಺༰ 

    &%/4CV⒎FSTJ[Fͷ࡟ݮ όΠτ   5$1΁ͷରԠ  ެࣜαΠτIUUQTEOTqBHEBZOFUJOEFYKBIUNM
  2. ֓ཁ *1ϑϥάϝϯςʔγϣϯ߈ܸ w ΩϟογϡϙΠζχϯά߈ܸͷͻͱͭ  )FS[CFSH 4IVMNBO͕೥ʹ࿦จൃද <> w ϑϥάϝϯτͨ͠%/4Ԡ౴ͷҰ෦Λࠩ͠ସ͑

     ୈҰϑϥάϝϯτศ৐߈ܸ΍ΞΠίϥ߈ܸͱΑ͹ΕΔ͜ͱ΋ w ࣮ࡍͷܦ࿏.56ΑΓখ͍͞αΠζͰ΋߈ܸՄೳ  3*1&Ͱ)MBWBDFL͕ൃද <> w ϙʔτϥϯμϚΠζͳͲͷैདྷͷରࡦ͕ແޮ  <>IUUQTBSYJWPSHBCT <>IUUQTVDTCJVBDJMdIFS[CFBTFDVSJUZGSBHQEG <>IUUQTJFFFYQMPSFJFFFPSHEPDVNFOU <>IUUQTSJQFSJQFOFUQSFTFOUBUJPOTJQGSBHBUUBDLQEG
  3. Πϝʔδ *1ϑϥάϝϯςʔγϣϯ߈ܸ  ୈϑϥάϝϯτ *1ϔομ 6%1ϔομ %/4ϝοηʔδͷҰ෦ ਖ਼نͷୈϑϥάϝϯτ *1ϔομ %/4ϝοηʔδͷ࢒Γ

    ୈϑϥάϝϯτ ِ૷ͨ͠ୈϑϥάϝϯτ *1ϔομ %/4ϝοηʔδͷ࢒Γ ਖ਼نͷݖҖαʔό͕ૹ৴͢Δύέοτ ߈ܸऀ͕ૹ৴͢Δύέοτ ߈ܸऀ͸ૹ৴͠ͳ͍ ਖ਼نͷԠ౴Λͦͷ··࢖༻ ผͷ಺༰ʹॻ͖׵͑ͨύέοτΛૹ৴ ِ૷ͨ͠ϑϥάϝϯτͱ ϦΞηϯϒϧِͤͯ͞ͷ Ԡ౴Λੜ੒
  4. ߈ܸͷྫ *1ϑϥάϝϯςʔγϣϯ߈ܸ  ਖ਼نͷԠ౴ ِ૷ͨ͠Ԡ౴ ;; ADDITIONAL SECTION: ns1.nodnssec.exp. 86400

    IN A 192.168.11.7 ns2.nodnssec.exp. 86400 IN A 192.168.11.8 ;; ADDITIONAL SECTION: ns1.nodnssec.exp. 86400 IN A 192.168.13.1 ns2.nodnssec.exp. 85389 IN A 192.168.13.1
  5. ߈ܸखॱ *1ϑϥάϝϯςʔγϣϯ߈ܸ  Ϧκϧό ݖҖαʔό ߈ܸऀ ᶃِ૷ͨ͠ ୈϑϥάϝϯτΛૹ৴ ᶄ໊લղܾཁٻ ᶅඇ࠶ؼ໰͍߹Θͤ

    ᶆୈϑϥάϝϯτΛૹ৴ ᶇୈϑϥάϝϯτΛૹ৴ ߈ܸ੒ޭͷ৔߹ɺᶇ͸ ϦΞηϯϒϧ͞Εͳ͍ ᶃͷύέοτͱ*1*%͕Ұக ͢Δ৔߹͸߈ܸ੒ޭ ᶃͱᶆ͕ϦΞηϯϒϧ
  6. %/44&$ *1ϑϥάϝϯςʔγϣϯ߈ܸ  $ dig chukyo-u.ac.jp @a.dns.jp +dnssec (snip) ;;

    flags: qr; QUERY: 1, ANSWER: 0, AUTHORITY: 6, ADDITIONAL: 2 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags: do; udp: 4096 ;; QUESTION SECTION: ;chukyo-u.ac.jp. IN A ;; AUTHORITY SECTION: chukyo-u.ac.jp. 86400 IN NS ns2.dc.ctc.ad.jp. chukyo-u.ac.jp. 86400 IN NS ns1.hs.ctc.jp. VJOG7GHBNE2GMJQ72U7J8DJBR9ECELQM.jp. 900 IN NSEC3 1 1 5 45EC942BAF VK94EPKGG2VSRBNU7V334S7O652C3M9K TXT RRSIG VJOG7GHBNE2GMJQ72U7J8DJBR9ECELQM.jp. 900 IN RRSIG NSEC3 8 2 900 20210111174503 20201212174503 18321 jp. tm6tSRCyhQyX0DiG25WVBDMIOtQ/QFC2tw0w1zTiBnvhfCfAhm0Rx8jk FDiRJonL/IDnPkJ7/ cE67fiuX0z8zcetIxlsjyOqn6HPzPjl2yb8JuLP SW5vvswZ0FDF09/6ZhmD1E/K6bu4BQW3nIuiqt8EF5K0JVVNA/XvS9a+ /cs= 9KH0DHR7PFV2TKURF2493MN2THE8GAPR.jp. 900 IN NSEC3 1 1 5 45EC942BAF 9KTFU2AI6RE43JIMPB56SAA33GIFG075 TXT RRSIG 9KH0DHR7PFV2TKURF2493MN2THE8GAPR.jp. 900 IN RRSIG NSEC3 8 2 900 20210111174503 20201212174503 18321 jp. jUqxDzJVq9VxqfKpOWCLNkhX/8CkuB1XkKp0GTzJHRmjk2oVs0ffkHEt 0nuLS9bMkfcg3NWC26r0j0DbKxx2P6pIlOFxjfI00h2/ OyCYR6C388R+ FUiOT4UX9w+LjktmLnz6Cb2bkw8nHaxIjKGEn7oELcfF0wCWqJQEsxq+ 0PE= ;; ADDITIONAL SECTION: ns2.dc.ctc.ad.jp. 86400 IN A 218.216.176.115 (snip) ;; MSG SIZE rcvd: 604 %0Ϗοτ͕Φϯʹͳ͍ͬͯΔͱ ॺ໊ݕূ͍ͯ͠ͳͯ͘΋334*(  /4&$  ϨίʔυͳͲ͕͍ͭͨ Ԡ౴͕ฦͬͯ͘Δ
  7. &%/4 *1ϑϥάϝϯςʔγϣϯ߈ܸ  $ dig chukyo-u.ac.jp @a.dns.jp +dnssec (snip) ;;

    flags: qr; QUERY: 1, ANSWER: 0, AUTHORITY: 6, ADDITIONAL: 2 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags: do; udp: 4096 ;; QUESTION SECTION: ;chukyo-u.ac.jp. IN A ;; AUTHORITY SECTION: chukyo-u.ac.jp. 86400 IN NS ns2.dc.ctc.ad.jp. chukyo-u.ac.jp. 86400 IN NS ns1.hs.ctc.jp. VJOG7GHBNE2GMJQ72U7J8DJBR9ECELQM.jp. 900 IN NSEC3 1 1 5 45EC942BAF VK94EPKGG2VSRBNU7V334S7O652C3M9K TXT RRSIG VJOG7GHBNE2GMJQ72U7J8DJBR9ECELQM.jp. 900 IN RRSIG NSEC3 8 2 900 20210111174503 20201212174503 18321 jp. tm6tSRCyhQyX0DiG25WVBDMIOtQ/QFC2tw0w1zTiBnvhfCfAhm0Rx8jk FDiRJonL/IDnPkJ7/ cE67fiuX0z8zcetIxlsjyOqn6HPzPjl2yb8JuLP SW5vvswZ0FDF09/6ZhmD1E/K6bu4BQW3nIuiqt8EF5K0JVVNA/XvS9a+ /cs= 9KH0DHR7PFV2TKURF2493MN2THE8GAPR.jp. 900 IN NSEC3 1 1 5 45EC942BAF 9KTFU2AI6RE43JIMPB56SAA33GIFG075 TXT RRSIG 9KH0DHR7PFV2TKURF2493MN2THE8GAPR.jp. 900 IN RRSIG NSEC3 8 2 900 20210111174503 20201212174503 18321 jp. jUqxDzJVq9VxqfKpOWCLNkhX/8CkuB1XkKp0GTzJHRmjk2oVs0ffkHEt 0nuLS9bMkfcg3NWC26r0j0DbKxx2P6pIlOFxjfI00h2/ OyCYR6C388R+ FUiOT4UX9w+LjktmLnz6Cb2bkw8nHaxIjKGEn7oELcfF0wCWqJQEsxq+ 0PE= ;; ADDITIONAL SECTION: ns2.dc.ctc.ad.jp. 86400 IN A 218.216.176.115 (snip) ;; MSG SIZE rcvd: 604 w %/4ͷ֦ு 3'$  w *1W %/44&$Ͱ͸ରԠඞਢ w 6%1Ͱ΋όΠτΛ௒͑Δ Ԡ౴ΛॲཧͰ͖Δ  ࠷େόΠτ
  8. %/44&$&%/4ͷӨڹ *1ϑϥάϝϯςʔγϣϯ߈ܸ  $ dig chukyo-u.ac.jp @a.dns.jp +dnssec (snip) ;;

    flags: qr; QUERY: 1, ANSWER: 0, AUTHORITY: 6, ADDITIONAL: 2 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags: do; udp: 4096 ;; QUESTION SECTION: ;chukyo-u.ac.jp. IN A ;; AUTHORITY SECTION: chukyo-u.ac.jp. 86400 IN NS ns2.dc.ctc.ad.jp. chukyo-u.ac.jp. 86400 IN NS ns1.hs.ctc.jp. VJOG7GHBNE2GMJQ72U7J8DJBR9ECELQM.jp. 900 IN NSEC3 1 1 5 45EC942BAF VK94EPKGG2VSRBNU7V334S7O652C3M9K TXT RRSIG VJOG7GHBNE2GMJQ72U7J8DJBR9ECELQM.jp. 900 IN RRSIG NSEC3 8 2 900 20210111174503 20201212174503 18321 jp. tm6tSRCyhQyX0DiG25WVBDMIOtQ/QFC2tw0w1zTiBnvhfCfAhm0Rx8jk FDiRJonL/IDnPkJ7/ cE67fiuX0z8zcetIxlsjyOqn6HPzPjl2yb8JuLP SW5vvswZ0FDF09/6ZhmD1E/K6bu4BQW3nIuiqt8EF5K0JVVNA/XvS9a+ /cs= 9KH0DHR7PFV2TKURF2493MN2THE8GAPR.jp. 900 IN NSEC3 1 1 5 45EC942BAF 9KTFU2AI6RE43JIMPB56SAA33GIFG075 TXT RRSIG 9KH0DHR7PFV2TKURF2493MN2THE8GAPR.jp. 900 IN RRSIG NSEC3 8 2 900 20210111174503 20201212174503 18321 jp. jUqxDzJVq9VxqfKpOWCLNkhX/8CkuB1XkKp0GTzJHRmjk2oVs0ffkHEt 0nuLS9bMkfcg3NWC26r0j0DbKxx2P6pIlOFxjfI00h2/ OyCYR6C388R+ FUiOT4UX9w+LjktmLnz6Cb2bkw8nHaxIjKGEn7oELcfF0wCWqJQEsxq+ 0PE= ;; ADDITIONAL SECTION: ns2.dc.ctc.ad.jp. 86400 IN A 218.216.176.115 (snip) ;; MSG SIZE rcvd: 604 w Ԡ౴͕ϑϥάϝϯτ͢ΔཁҼʹ  6%1Ͱॲཧ͢ΔԠ౴αΠζ͕ େ͖͘ͳΔ  ॺ໊ݕূ͠ͳ͍ͳΒ334*(  /4&$  ͳͲ͸ෆཁ ‣ Ԡ౴αΠζ͕૿͑Δ͚ͩ ‣ ʹ΋ؔΘΒͣ%0ϏοτΛΦϑ ʹͰ͖ͳ͍࣮૷͕͋Δ 6OCPVOEͱ͔ ॺ໊ݕূ͠ͳ͍ͳΒෆཁ
  9. w 6%1ٖࣅϔομɺ6%1ϔομɺϖΠϩʔυ͔Βܭࢉ  ߈ܸऀ͸͜ͷ஋ΛҰகͤ͞ͳ͍ͱ͍͚ͳ͍ TPVSDFBEESFTT EFTUJOBUJPOBEESFTT [FSP QSPUPDPM 6%1MFOHUI TPVSDFQPSU

    EFTUJOBUJPOQPSU -FOHUI $IFDLTVN QBZMPBE 6%1νΣοΫαϜ *1ϑϥάϝϯςʔγϣϯ߈ܸ  6%1ٖࣅϔομ 6%1ϔομ
  10. 6%1νΣοΫαϜ *1ϑϥάϝϯςʔγϣϯ߈ܸ w ܭࢉํ๏ͷิ਺࿨ͷͷิ਺  ྫ03 64 6e 73 c0

    0c 03 64 6e 73 c0 0c 01 31 e3 31 e4 ᶃ όΠτͣͭՃࢉ ᶄ ্ܻ͕ΓΛ࠷ԼҐʹՃࢉ 01 31 e3 ᶅ ͷิ਺ΛٻΊΔ ൱ఆ ce 1b ^ 31 e4 νΣοΫαϜ
  11. 6%1νΣοΫαϜͷِ૷ *1ϑϥάϝϯςʔγϣϯ߈ܸ w νΣοΫαϜ͸ຖճมԽ w Ԡ౴಺༰ͱϑϥάϝϯτҐஔ͕ҰఆͳΒɺ൪໨Ҏ߱ͷ ϖΠϩʔυ͸ෆม w ϑϥάϝϯτ͝ͱʹิ਺࿨ͷܭࢉ͕Ұக͢Ε͹Α͍ w

    ߈ܸऀ͸ࣄલʹԠ౴Λ༻ҙͯ͠
 νΣοΫαϜ͕Ұக͢ΔΑ͏ʹ
 ِ૷Ͱ͖Δ    ͳΒ͹  ͷิ਺࿨ Csum = Csum1 + Csum2 Csum′ = Csum1 + Csum′ 2 Csum2 = Csum′ 2 Csum = Csum′ Csum :
  12. 1BUI.564QPPGJOH *1ϑϥάϝϯςʔγϣϯ߈ܸ w ֎෦͔Βِ૷*$.1ύέοτΛૹ৴  ϑϥάϝϯτΛ༠ൃ w *1Wʹ͓͚ΔӨڹ  -JOVY͋Γ

    ,FSOFMͰ֬ೝ   'SFF#4%ͳ͠  ߈ܸऀ Ϧκϧό ݖҖαʔό ૹ৴ݩΛϦκϧό ʹِ૷ͨ͠ΫΤϦΛ ૹ৴ Ϩεϙϯε ِ૷*$.1 ύέοτͷૹ৴
  13. *1ϔομ *1ϑϥάϝϯςʔγϣϯ߈ܸ w ΞυϨεɺϑϥάɺΦϑηοτͳͲΛҰகͤ͞Δ  7FSTJPO *)- 5ZQFPG4FSWJDF 5PUBM-FOHUI *EFOUJpDBUJPO

     % ' . ' 'SBHNFOU0⒎TFU 5JNFUP-JWF 1SPUPDPM )FBEFS$IFDLTVN 4PVSDF"EESFTT %FTUJOBUJPO"EESFTT 0QUJPOT 1BEEJOH *1Wϔομ
  14. *1*EFOUJGJDBUJPO *1ϑϥάϝϯςʔγϣϯ߈ܸ w *1WϏοτ w ߈ܸऀ͸༧ଌ͢Δඞཁ͕͋Δ  7FSTJPO *)- 5ZQFPG4FSWJDF

    5PUBM-FOHUI *EFOUJpDBUJPO  % ' . ' 'SBHNFOU0⒎TFU 5JNFUP-JWF 1SPUPDPM )FBEFS$IFDLTVN 4PVSDF"EESFTT %FTUJOBUJPO"EESFTT 0QUJPOT 1BEEJOH
  15. *1*EFOUJGJDBUJPO *1ϑϥάϝϯςʔγϣϯ߈ܸ w ͜ͷ஋͚ͩ༧ଌ͢Ε͹Α͍ w ߈ܸͷΤϯτϩϐʔ͕Ϗοτʹ௿Լ  7FSTJPO *)- 5ZQFPG4FSWJDF

    5PUBM-FOHUI *EFOUJpDBUJPO  % ' . ' 'SBHNFOU0⒎TFU 5JNFUP-JWF 1SPUPDPM )FBEFS$IFDLTVN 4PVSDF"EESFTT %FTUJOBUJPO"EESFTT 0QUJPOT 1BEEJOH *1Wϔομ
  16. *1W΍5$1ͷ৔߹͸ *1ϑϥάϝϯςʔγϣϯ߈ܸ w *1W*1*EFOUJpDBUJPO͕Ϗοτ  ैདྷͷ߈ܸͱൺֱͯ͠Τϯτϩϐʔͷ͕ࠩͳ͍ ‣ 6%1ιʔεϙʔτ Ϗοτ ͱτϥϯβΫγϣϯ*%

    Ϗοτ ͷ ߹ܭͱಉ͡ w 5$11BUI.56TQPPpOH͢ΔͱϑϥάϝϯτͰ͸ͳ͘ ηάϝϯςʔγϣϯ͢Δ  ൪໨Ҏ߱ͷύέοτʹ΋5$1ϔομ͕ೖΔ 
  17. ҕৡԠ౴ͷࠩ͠ସ͑ ΞλοΫϕΫλ w ॺ໊κʔϯ͔Βະॺ໊κʔϯ΁ͷҕৡԠ౴Λ߈ܸ  ॺ໊ݕূ༗ޮ࣌Ͱ΋߈ܸՄೳͳέʔε΋ ‣ /4&$0QU0VU͕༗ޮͳκʔϯͷ0QU0VU۠ؒ΁ͷҕৡ ‣ ॺ໊πʔϧʹґଘ

    w ର৅κʔϯ͕Ωϟογϡʹଘࡏ͠ͳ͍৔߹ʹ༗ޮ w େྔͷ/4Λ࣋ͭ৔߹΍/4ͷϥϕϧ͕௕͍৔߹͸ΑΓةݥ  /4&$334*(͕ͳͯ͘΋ϑϥάϝϯτͤ͞ΒΕΔՄೳੑ 
  18. TJCMJOHEPNBJOͷHMVFϨίʔυͷࠩ͠ସ͑ ΞλοΫϕΫλ w ߈ܸऀࣗ਎͕υϝΠϯ໊Λ༻ҙ  TJCMJOHEPNBJOͷ/4ʹҕৡ ͍ͯ͠ΔΑ͏ʹΈ͔͚ͤ  "EEJUJPOBMηΫγϣϯͷ
 """""ϨίʔυΛِ૷

    w ِ૷ର৅ͷϨίʔυ͕͢Ͱʹ
 Ωϟογϡ͞Ε͍ͯΔ৔߹ʹ
 ্ॻ͖Մೳ͔Ͳ͏͔͸࣮૷ґଘ  TJCMJOHEPNBJOͷ/4Ϩίʔυ ஔ͖׵͑ର৅ͷϨίʔυ
  19. ൱ఆԠ౴ͷࠩ͠ସ͑ ΞλοΫϕΫλ w ϝδϟʔͳ044࣮૷͸ରࡦࡁΈ  #*/% ,OPU3FTPMWFS͸Өڹͳ͠ #*/%1 ,OPU3FTPMWFSͰ֬ೝ 

     6OCPVOE <> 1PXFS%/43FDVSTPS <>Ͱमਖ਼ࡁΈ w ॺ໊κʔϯ΁%0ϏοτΛΦϯʹͯ͠໰͍߹ΘͤΔ৔߹Λ૝ఆ w Өڹ  ॺ໊ະݕূυϝΠϯϋΠδϟοΫ  ॺ໊ݕূ࣌/4&$0QU0VU۠ؒ΁αϒυϝΠϯΠϯδΣΫγϣϯͰ͖ΔՄೳੑ w ࿈ଓ߈ܸ͕Մೳ  <>IUUQTXXXOMOFUMBCTOMOFXT%FDVOCPVOESFMFBTFE <>IUUQTHJUIVCDPN1PXFS%/4QEOTQVMM
  20. ൱ఆԠ౴ͷࠩ͠ସ͑ ΞλοΫϕΫλ w ҎԼʹج͍ͮͨ߈ܸ  3'$ͷSBOLJOHEBUB  3'$ͷ൱ఆԠ౴ͷྫ  ݖҖ͋ΔԠ౴ͷ"OTXFSηΫγϣϯʹؚ·ΕΔݖҖ͋Δσʔλ

    ݖҖ͋ΔԠ౴ͷ"VUIPSJUZηΫγϣϯʹؚ·ΕΔσʔλ ݖҖͷͳ͍Ԡ౴ͷ"OTXFSηΫγϣϯͷσʔλ ݖҖ͋ΔԠ౴ͷ"OTXFSηΫγϣϯʹؚ·ΕΔݖҖͷͳ͍σʔλ ݖҖ͋ΔԠ౴ͷ"EEJUJPOBMηΫγϣϯͷσʔλ ݖҖͷͳ͍Ԡ౴ͷ"VUIPSJUZηΫγϣϯͷσʔλ ݖҖͷͳ͍Ԡ౴ͷ"EEJUJPOBMηΫγϣϯͷσʔλ ৴པ౓ ߴ ௿ 3'$SBOLJOHEBUB
  21. ൱ఆԠ౴ͷࠩ͠ସ͑ ΞλοΫϕΫλ w ҎԼʹج͍ͮͨ߈ܸ  3'$ͷSBOLJOHEBUB  3'$ͷ൱ఆԠ౴ͷྫ  )FBEFS

    3%$0%&/9%0."*/ 2VFSZ "/&9".1-&" "OTXFS FNQUZ "VUIPSJUZ &9".1-&40"/499)045."45&3/499 &9".1-&/4/499 &9".1-&/4/499 "EEJUJPOBM FNQUZ 3'$ͷ൱ఆԠ౴ͷྫΛࢀߟʹͨ͠දه ͜ΕΛ࠶ݱ Ԡ౴ͷྫ͕ޡ͍ͬͯͨͷͰ3'$Λࢀߟʹͨ͠΋ͷʹमਖ਼͠·ͨ͠ɻ ͳ͓ɺ3'$ͷ/9%0."*/ͷྫͦͷ··Ͱ͸/4Ϩίʔυ͕֎෦໊ͱͳ͍ͬͯΔͨΊ༗ޮͳಟʹͳΓ·ͤΜɻ
  22. ݖҖɾϦκϧό૒ํͷରࡦ ରࡦ w ׬શͳରࡦ͸ࠔ೉  %'ϑϥάΛཱͯΔͱ.56ͷখ͍͞ܦ࿏Ͱ෭࡞༻ ‣ Ԡ౴Λड৴Ͱ໊͖ͣલղܾ͕ࣦഊ͢ΔՄೳੑ w ؇࿨ࡦ

     &%/4CV⒎FSTJ[FΛখ͘͞͠ɺେ͖͍Ԡ౴͸5$1ϑΥʔϧόοΫ ‣ qBHEBZͰ͸όΠτΛਪ঑ ‣ චऀΒ͸όΠτΛਪ঑ 
  23. ݖҖɾϦκϧό૒ํͷରࡦ ରࡦ w %/44&$΁ͷ׬શͳରԠ  /4&$0QU0VU΋ແޮʹ  ීٴ్্͕ةݥ ‣ Ϧκϧόͷ%0Ϗοτ͕༗ޮͩͱະॺ໊κʔϯ΁ͷҕৡԠ౴ʹ/4&$

    334*(͕෇Ճ ‣ 4IVMNBOΒ<> ͷࢦఠ  "incremental DNSSEC deployment is vulnerable to our cache poisoning attacks, and complete adoption of DNSSEC may take considerable time, since it depends on adoption by both name server and resolver."
  24. ݖҖαʔόଆ ରࡦ w 1.56%ͷ݁ՌΛແࢹ  -JOVY,FSOFMҎ߱ͷIP_PMTUDISC_OMITιέοτΦϓγϣϯΛ༗ޮʹ  04ͱݖҖαʔό࣮૷྆ํͷରԠ͕ඞཁ ‣ #*/%Ҏ߱<>

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