Tweet
Tweet

Slide 1

Slide 1 text

ୈ̎ষɹϓϩτίϧ ೥ɹ݄೔ ϓϩϑΣογϣφϧ44-5-4ྠಡձ Shuya OSAKI (@4huya)
 Keio University

Slide 2

Slide 2 text

3FDPSEϓϩτίϧ ֊૚Խ͞Εͨ5-4ϓϩτίϧ 2 ɾ5-43FDPSEϓϩτίϧɹɹɹŠ҉߸ԽͷॲཧΛ୲͏ ɾ5-4)BOETIBLFϓϩτίϧŠ҉߸ԽҎ֎ͷॲཧΛ୲͏ɾ̐ͭʹࡉ෼Խ͞ΕΔ )551 5-43FDPSEϓϩτίϧ )BOETIBLF
 ϓϩτίϧ $IBOHF$JQIFS4QFD
 ϓϩτίϧ "MFSU
 ϓϩτίϧ "QQMJDBUJPO%BUB
 ϓϩτίϧ 5-4)BOETIBLFϓϩτίϧ 5-4ϓϩτίϧ

Slide 3

Slide 3 text

3FDPSEϓϩτίϧ 3 https://hpbn.co/transport-layer-security-tls/ 3FDPSEϓϩτίϧͷ໾ׂ ɾ ϝοηʔδͷసૹ ‣ Ϩίʔυ௕ʹ߹Θͤͯϑϥάϝϯτʹͨ͠Γɺෳ਺ͷόοϑΝΛ୯ҰϨίʔυʹ·ͱΊΔ ɾ ҉߸Խ͓Αͼ׬શੑͷݕূ ‣ ωΰγΤʔγϣϯͨ͠ύϥϝʔλʹج͍ͮͨɺϨίʔυ૚ʹΑΔ҉߸Խɾ׬શੑͷݕূ ɾ ѹॖ ‣ ඇਪ঑ɻ$*3*.&߈ܸ ηογϣϯϋΠδϟοΫ ΍ɺѹॖ͞Εͨίϯςϯπ ը૾౳ ͷ࠶ѹॖ͕ى͖Δɻ ɾ ֦ுੑ ‣ 3FDPSEϓϩτίϧ͸σʔλసૹͱ҉߸ॲཧΛ୲͏ɻଞͷػೳ͸αϒϓϩτίϧͰ֦ு͢Δɻ 5-43FDPSEͷߏ଄

Slide 4

Slide 4 text

)BOETIBLFϓϩτίϧ 4 )BOETIBLFϓϩτίϧͷ໾ׂ ɾ 5-4)BOETIBLFϓϩτίϧͷ̍ͭ 5-4)BOETIBLF)BOETIBLF  ɾ ڞ༗伴Λੜ੒͠ɺূ໌ॻͷަ׵Λߦ͏ ‣ ڞ༗伴ͷੜ੒ɹŠɹ҉߸௨৴Λߦ͏ͨΊ ‣ ূ໌ॻͷަ׵ɹŠɹ૬खΛೝূ͢ΔͨΊ ɾ )BOETIBLFͷҰൠతͳྲྀΕ ᶃαʔόೝূΛ൐͏ϑϧϋϯυγΣΠΫ ᶄηογϣϯΛ࠶։͢Δ৔߹ͷɺҰ෦ϝοηʔδΛলུͨ͠ϋϯυγΣΠΫ ᶅΫϥΠΞϯτͱαʔόͷೝূΛ൐͏ϋϯυγΣΠΫ )BOETIBLFϓϩτίϧ NTH@UZQF MFOHUI )BOETIBLF
 σʔλ όΠτ NTH@UZQF )BOETIBLFσʔλ Y )FMMP3FRVFTU Y $MJFOU)FMMP Y 4FSWFS)FMMP YC $FSUJpDBUF YD 4FSWFS,FZ&YDIBOHF YE $FSUJpDBUF3FRVFTU YF 4FSFWFS)FMMP%POF YG $FSUJpDBUF7FSJGZ Y $MJFOU,FZ&YDIBOHF Y 'JOJTIFE

Slide 5

Slide 5 text

ϑϧϋϯυγΣΠΫ 5 5-4ηογϣϯͷཱ֬ 2.2 Handshake Ϋϥ Π Ξϯ τ αʔό  $MJFOU)FMMP 4FSWFS)FMMP $FSUJpDBUF 4FSWFS)FMMP%POF $MJFOU,FZ&YDIBOHF <$IBOHF$JQIFS4QFD> 'JOJTIFE 4FSWFS,FZ&YDIBOHF        <$IBOHF$JQIFS4QFD> 'JOJTIFE   p.27ΑΓ αʔόೝূΛ൐͏ϑϧϋϯυγΣΠΫ 5$1ϋϯυγΣΠΫ
 Š#FGPSFŠ
 ⁞ΫϥΠΞϯτ͕৽نͷϋϯυγΣΠΫ
 ɹΛ։࢝ɺฏจͰಈ࡞࢓༷Λૹ৴  ಈ࡞࢓༷ʹैͬͯ҉߸Խʹඞཁͳ
 ɹύϥϝʔλΛϨεϙϯε͢Δ ⁣҉߸Խʹඞཁͳ৚͕݅߹ҙ͞ΕͨΒ
 ηογϣϯʹඞཁͳڞ௨伴Λੜ੒͢Δ
 ⁦҉߸௨৴ʹ੾Γସ͑."$Λૹ৴͢Δ
 Š"GUFSŠ
 ΞϓϦέʔγϣϯσʔλͷૹड৴ 355

Slide 6

Slide 6 text

ϑϧϋϯυγΣΠΫ 6 $MJFOU)FMMP ɾ৽نͷϋϯυγΣΠΫͰ࠷ॳʹૹ৴͞ΕΔϝοηʔδ ɾΫϥΠΞϯτ͸͜ΕͰಈ࡞࢓༷Λαʔόʹ఻͑Δ 28 ୈ2ষ ϓϩτίϧ Լهʹ ClientHello ͷϝοηʔδྫΛࣔ͠·͢ɻݟ΍͍͢Α͏ʹ༨෼ͳ৘ใ͸औΓআ͍ͯ ͋Γ·͕͢ɺॏཁͳϙΠϯτ͸͢΂ؚͯ·Ε͍ͯ·͢ɻ Handshake protocol: ClientHello Version: TLS 1.2 Random Client time: May 22, 2030 02:43:46 GMT Random bytes: b76b0e61829557eb4c611adfd2d36eb232dc1332fe29802e321ee871 Session ID: (ۭ) Cipher Suites Suite: TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 Suite: TLS_DHE_RSA_WITH_AES_128_GCM_SHA256 Suite: TLS_RSA_WITH_AES_128_GCM_SHA256 Suite: TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA Suite: TLS_DHE_RSA_WITH_AES_128_CBC_SHA Suite: TLS_RSA_WITH_AES_128_CBC_SHA Suite: TLS_RSA_WITH_3DES_EDE_CBC_SHA Suite: TLS_RSA_WITH_RC4_128_SHA Compression methods Method: null Extensions Extension: server_name Hostname: www.feistyduck.com Extension: renegotiation_info Extension: elliptic_curves Named curve: secp256r1 Named curve: secp384r1 Extension: signature_algorithms Algorithm: sha1/rsa Algorithm: sha256/rsa Algorithm: sha1/ecdsa Algorithm: sha256/ecdsa p.28ΑΓ w 7FSTJPO ‣ αϙʔτ͢Δ5-4ͷόʔδϣϯ w 3BOEPN ‣ ϋϯυγΣΠΫΛҰҙʹ͢Δཚ਺ w 4FTTJPO*% ‣ ࠷ॳͷ઀ଓͰ͸৽ن઀ଓΛۭࣔ͢ w $JQIFS4VJUF ‣ ରԠՄೳͳ҉߸εΠʔτ w $PNQSFTTJPONFUIPET ‣ ѹॖํࣜͷࢦఆɺઈରOVMM w &YUFOTJPOT ‣ ֦ு৘ใͷεϖʔε ClientHello
 ϝοηʔδྫ

Slide 7

Slide 7 text

ϑϧϋϯυγΣΠΫ 7 4FSWFS)FMMP ɾαʔό͕઀ଓͰ࢖͏ύϥϝʔλΛΫϥΠΞϯτʹฦ౴͢Δɻ ɾߏ଄͸$MJFOU)FMMPͱಉ͡ɺ஋͸αʔό͕ΫϥΠΞϯτʹఏҊ͢Δ΋ͷ͕ೖΔɻ $FSUJpDBUF ɾαʔό͔ΒΫϥΠΞϯτ΁9ূ໌ॻνΣʔϯΛҾ͖౉͢ɻ ɾূ໌ॻνΣʔϯʹ͸αʔόͷূ໌ॻ͔Βূ໌ॻʹॺ໊͢Δೝূہͷূ໌ॻ͕࿈ͳΔɻ 4FSWFS,FZ&YDIBOHF ɾ伴ަ׵ʹඞཁͳ෇ՃతͳσʔλΛૹΔɻ$FUJpDBUFͷิ଍ɻ 4FSWFS)FMMP%POF ɾ4FSWFS)FMMP͔ΒͷҰ࿈ͷϝοηʔδͷऴΘΓΛࣔ͢ɻ

Slide 8

Slide 8 text

ϑϧϋϯυγΣΠΫ 8 $MJFOU,FZ&YDIBOHF ɾ伴ަ׵ʹඞཁͳ৘ใΛΫϥΠΞϯτ͔Βૹ৴ ɾ&YϓϨϚελʔγʔΫϨοτ 34" ɺ%J⒏F)FMMNBOެ։஋ %)伴ަ׵ $IBOHF$JQIFS4QFD ɾ)BOETIBLFϝοηʔδͰ͸ͳ͘ɺ5-4)BOETIBLFͷαϒϓϩτίϧ ɾ)BOETIBLFϓϩτίϧͰܾఆͨ͠ಈ࡞࢓༷ΛΫϥΠΞϯτʹ௨஌ 'JOJTIFE ɾϋϯυγΣΠΫͷ׬ྃΛࣔ͠ɺ҉߸Խ͞ΕͨϝοηʔδͰ͋Δ ɾWFSJGZ@EBUBϑΟʔϧυͰμΠδΣετΛͱΓɺվ͟ΜΛ೉͘͢͠Δ

Slide 9

Slide 9 text

ΫϥΠΞϯτೝূ 9 ૬ޓೝূΛߦ͏ p.32ΑΓ ΫϥΠΞϯτೝূͷ৔߹ͷϑϧϋϯυγΣΠΫ 355 ͠ɺࣗ਎ͷ Certificate ϝοηʔδΛૹΓʢ͜ͷͱ͖ͷϑΥʔϚοτ͸αʔ ૹΔͷʹ࢖͏ Certificate ϝοηʔδͱಉ͡Ͱ͢ʣ ɺରԠ͢ΔൿີݤΛ࣋ͬ CertificateVerify ϝοηʔδΛ࢖ͬͯূ໌͠·͢ʢਤ2.3ʣ ɻ Ϋϥ Π Ξϯ τ αʔό  $MJFOU)FMMP 4FSWFS)FMMP $FSUJpDBUF 4FSWFS)FMMP%POF $MJFOU,FZ&YDIBOHF <$IBOHF$JQIFS4QFD> $FSUJpDBUF 4FSWFS,FZ&YDIBOHF      <$IBOHF$JQIFS4QFD> 'JOJTIFE   $FSUJpDBUF3FRVFTU   'JOJTIFE $FSUJpDBUF7FSJGZ    ɾαʔό͕ΫϥΠΞϯτʹೝূΛٻΊΔ ɾ$FSUJpDBUF3FRVFTUϝοηʔδͰ
 ҎԼʹै͏ূ໌ॻΛཁٻ͢Δ ‣ αʔό͕ཧղͰ͖Δূ໌ॻͷλΠϓ ‣ αʔό͕ཧղͰ͖Δೝূہͷ໊લ ɾΫϥΠΞϯτ͸$FSUJpDBUFϝοηʔδ ͰԠ౴͢Δ ɾ$FSUJpDBUF7FSJGZϝοηʔδͰରԠ͢Δ ൿີ伴ͷॴ༗Λࣔ͢

Slide 10

Slide 10 text

ϑϧϋϯυγΣΠΫ 10 $FSUJpDBUF3FRVFTU ɾΫϥΠΞϯτʹରͯ͠ೝূͷཁٻΛߦ͏ ɾαʔό͕ର৅ͱ͢Δূ໌ॻͷެ։伴͓Αͼॺ໊ΞϧΰϦζϜͷ఻ୡʹ༻͍ΒΕΔ $FSUJpDBUF7FSJGZ ɾΫϥΠΞϯτূ໌ॻͷൿີ伴ͷอ༗Λࣔ͢

Slide 11

Slide 11 text

ηογϣϯϦβϯϓγϣϯ 11 ཱ֬ࡁΈͷηογϣϯͷ࠶։ ɾϑϧϋϯυγΣΠΫʹ͸Φʔόʔϔου͕൐͏ ɾ4FTTJPO*%Λ༻͍ͯηογϣϯͷ࠶։ΛՄೳʹ͢Δ࢓૊Έ Session ID ϑΟʔϧυΛࢀরʣ ɻΫϥΠΞϯτͱαʔό͸ɺ׬શͳωΰγΤʔγ ཱ֬ͨ͠઀ଓ͕ऴྃͨ͋͠ͱ΋ɺ͜ͷSession ID ΛҰఆظؒ͸อ࣋͠·͢ɻ ΫϥΠΞϯτ͸ɺҎલͷηογϣϯΛ࠶։͠Α͏ͱ͢Δ৔߹ɺClientHell ద੾ͳ Session ID ΛؚΊͯૹ৴͠·͢ɻαʔό͸ɺ౰֘ͷηογϣϯΛ࠶։͢ ৔߹ɺಉ͡Session ID ΛServerHello ϝοηʔδʹؚΊͯૹΓฦ͠·͢ɻͦ͠ ͨ͠ϚελʔγʔΫϨοτΛ࢖ͬͯ৽͍͠҉߸ݤʢ҉߸Խʹ࢖͏ݤ΍MACݤͳ ҉߸௨৴΁ͱҠߦ͔ͯ͠ΒɺFinished ϝοηʔδΛૹΓ·͢ɻΫϥΠΞϯτ͸ ͕࠶։͞Εͨ͜ͱΛ֬ೝͨ͠Βɺαʔόͱಉ͜͡ͱΛ͠·͢ɻ݁Ռతʹϋϯυγ ͳΓɺωοτϫʔΫ্ͷ΍ΓऔΓ͕Ұԟ෮͚ͩͰࡁΈ·͢ʢਤ2.4ʣ ɻ Ϋϥ Π Ξϯ τ αʔό  $MJFOU)FMMP 4FSWFS)FMMP <$IBOHF$JQIFS4QFD> 'JOJTIFE      <$IBOHF$JQIFS4QFD> 'JOJTIFE $IBOHF$JQIFS4QFDϓϩ τ ίϧͷϝ ο ηʔ δ <> p.33ΑΓ লུ͞Εͨ5-4ϋϯυγΣΠΫ ɾ αʔό͸ηογϣϯʹ4FTTJPO*%Λ
 ׂΓ౰ͯΔ ɾ 4FTTJPO*%͸4FSWFS)FMMPͰૹ৴͢Δ ɾ ηογϣϯΛ࠶։࣌͸ΫϥΠΞϯτ͕
 $MJFOU)FMMPʹҎલͷ4FTTJPO*%Λૠೖ ɾ ηογϣϯνέοτͱݺ͹ΕΔํ๏΋͋Δ 355

Slide 12

Slide 12 text

伴ަ׵ 12 5-4Ͱ༻͍ΒΕΔ伴ަ׵ΞϧΰϦζϜ ɾ 5-4Ͱ͸ଟ͘ͷ伴ަ׵ΞϧΰϦζϜΛαϙʔτ͢Δ ɾ Ͳͷ҉߸εΠʔτ͕࢖ΘΕΔ͔͸ωΰγΤʔγϣϯʹΑΓܾ·Δ ओͳ伴ަ׵ΞϧΰϦζϜ ɾ 34" ‣ σϑΝΫτελϯμʔυɻαʔόͷൿີ伴Λ༻͍ΔͨΊɺ1'4 1FSGFDU'PSXBSE4FDSFZ Ͱͳ͍ɻ ɾ %)&@34" ‣ ΫϥΠΞϯτɾαʔόͷ྆ऀͰڞ௨ͷ伴Λੜ੒͢Δɻ34"ʹΑΔೝূΛซ༻͢Δɻ1'4͕͋Δɻ ɾ &$%)&@34"ɾ&$%)&@&$%4" ‣ ପԁۂઢ҉߸ &$ ʹجͮ͘伴ަ׵ΞϧΰϦζϜɻ ‣ ֓೦తʹ͸%)&ͱಉ͡伴ಉҙΞϧΰϦζϜ͕ͩɺॲཧ͕ߴ଎ɻ

Slide 13

Slide 13 text

34"伴ަ׵ 13 34"ͷ҉߸Խɾ෮߸ʹར༻Մೳͳੑ࣭Λ༻͍Δ 34"伴ަ׵ͷखॱ ‣ ΫϥΠΞϯτ͸ϓϦϚελʔγʔΫϨοτΛੜ੒ όΠτͷཚ਺  ‣ ͦΕΛαʔόͷެ։伴Ͱॺ໊͠ɺ$MJFOU&YDIBOHFϝοηʔδͰૹ৴ ‣ αʔό͸ϝοηʔδͷϓϦϚελʔγʔΫϨοτΛαʔόͷൿີ伴Ͱ෮߸͠ೖख ɾ ൿີ伴͕ೖख͞ΕΔͱɺ߈ܸऀ΋ϓϦϚελʔγʔΫϨοτΛੜ੒Ͱ͖Δ໰୊ ɾ ཁ͸τϥϑΟοΫΛஷΊ͓͚ͯ͹5-4௨৴Ͱ΋伴ׂ͕ΕͨॠؒʹղಡͰ͖Δ ɾ /4"͸աڈͷτϥϑΟοΫΛ5-4ͷ··อ؅͍ͯ͠Δͱ·͜ͱ͠΍͔ʹ͞͞΍͔ΕΔʜ ɾ ͔ͩΒࠓͰ͸1'4 લํൿಗੑ ͕͋Δଞͷ伴ަ׵ΞϧΰϦζϜ͕ਪ঑͞ΕΔ ‣ 34"ͷΑ͏ʹ伴͕࿙Εͯ΋ɺηογϣϯͷ෮߸͕Ͱ͖ͳ͍͜ͱ

Slide 14

Slide 14 text

%J⒏F)FMMNBO伴ަ׵ 14 ڞ༗͢Δ伴ΛܭࢉʹΑͬͯಋग़ ɾ %)伴ަ׵ͷखॱ ‣ লུʂ ͳΜͱͳ͔͘͠෼͔ΒΜʜ  ‣ ҉߸ٕज़ೖ໳ͷQΛಡΜͰ͘Ε %)伴ަ׵ͷ໰୊఺ ɾ %)ύϥϝʔλͷηΩϡϦςΟ ‣ ύϥϝʔλͷڧ͞ʹηογϣϯͷ҆શੑ͕ࠨӈ͞ΕΔ ɾ %)ύϥϝʔλͷωΰγΤʔγϣϯ ‣ ωΰγΤʔγϣϯͷ݁ՌʹΑͬͯ͸ɺظ଴͢Δڧ౓ͷύϥϝʔλ͕࢖༻Ͱ͖ͳ͍ ɾ ෆे෼ͳύϥϝʔλͷڧ౓ ‣ -PHKBN߈ܸʹΑΓύϥϝʔλʹ͋Δఔ౓ͷڧ౓͕ඞཁͰ͋Δ͜ͱ͕ࣔ͞Εͨ

Slide 15

Slide 15 text

ପԁۂઢ%J⒏F)FMMNBO伴ަ׵ 15 ପԁۂઢ্ͷ཭ࢄର਺໰୊ ɾ %)伴ަ׵ͷखॱ ‣ লུʂ ͬͪ͜͸ϚδͰ෼͔ΒΜʜ  ‣ ҉߸ٕज़ೖ໳ͷQΛಡΜͰ͘Ε ɾ &$%)&ͷํ͕୹͍伴௕͔ͭߴ͍ηΩϡϦςΟ͕࣮ݱͰ͖Δ ‣ ύϥϝʔλͷڧ͞ʹηογϣϯͷ҆શੑ͕ࠨӈ͞ΕΔ

Slide 16

Slide 16 text

ೝূ 16 ೝূͱ伴ަ׵͸Ұମ ɾ 5-4Ͱ͸ίετΛ࡟ݮ͢ΔͨΊɺೝূͱ伴ަ׵͸ҰମͰߦΘΕΔ ɾ ೝূ͸ূ໌ॻΛར༻ͨ͠ެ։伴҉߸ํ͕ࣜҰൠ ɾ 34"ʹΑΔ伴ަ׵ ‣ ΫϥΠΞϯτ͕ϥϯμϜͳ஋ΛϓϦϚελʔγʔΫϨοτͯ͠ੜ੒ ‣ ͦΕΛαʔόͷެ։伴Ͱॺ໊͠ૹ৴ ɾ %)&͓Αͼ&$%)&ʹΑΔ伴ަ׵ ‣ αʔό͸ύϥϝʔλʹॺ໊Λߦ͏ ‣ ΫϥΠΞϯτ͸ݕূ͞Εͨূ໌ॻ͔ΒରԠ͢Δެ։伴Λऔಘ ‣ ެ։伴Λ༻͍ͯॺ໊͞ΕͨύϥϝʔλΛݕূ͢Δ ‣ ύϥϝʔλ͸ηογϣϯ͝ͱʹҰҙ͕ͩɺಛఆͷঢ়گԼͰ߈ܸऀ͕ϥϯμϜͳ஋Λಉظͤͯ͞αʔόͷ
 ॺ໊Λ࠶ར༻͢Δ-PHKBN߈ܸ͕͋Δ

Slide 17

Slide 17 text

҉߸Խ 17 ଟ਺ͷ҉߸ΞϧΰϦζϜΛαϙʔτ͢Δ5-4 ɾ 5-4Ͱ͸༷ʑͳΞϧΰϦζϜΛ༻͍ͯɺΞϓϦέʔγϣϯσʔλΛ҉߸ԽͰ͖Δ ‣ ݱࡏɺ࠷΋Ұൠతͳͷ͸"&4 3JKOEBFM  ɾ 5-4Ͱར༻Ͱ͖Δ҉߸Խ͸छྨʹ෼ྨͰ͖Δ ‣ ετϦʔϜ҉߸Խํࣜ ‣ ϒϩοΫ҉߸Խํࣜ ‣ "&"% ೝূ෇͖҉߸

Slide 18

Slide 18 text

ετϦʔϜ҉߸Խํࣜ 18 ҉߸Խ͸ஈ֊ͰߦΘΕΔ ɾ Ϩίʔυͷγʔέϯε൪߸ɾ3FDPSEϔομɾฏจσʔλͷ݁߹ͷ."$ΛͱΔ ‣ ."$ͷܭࢉʹ3FDPSEϔομؚ͕·Ε͍ͯΔͨΊɺσʔλ͕վ͟Μ͞Ε͍ͯͳ͍͜ͱΛࣔͤΔ ‣ ."$ͷܭࢉʹγʔέϯε൪߸ؚ͕·Ε͍ͯΔͨΊɺਖ਼͍͠ύέοτ ϦϓϨΠ߈ܸͰͳ͍ Ͱ͋Δ ɾ ."$ͱฏจσʔλͱΛ҉߸Խ͢Δ 2.5 ҉߸Խ 41 ҉߸จ ೝূ ."$ ҉߸Խ ϔο μ γʔέϯε൪߸ ϔο μ ฏจ ฏจ ετϦʔϜ҉߸Խํࣜ p.41ΑΓ

Slide 19

Slide 19 text

ϒϩοΫ҉߸Խํࣜ 19 42 ୈ2ষ ϓϩτίϧ ฏจ ೝূ ."$ ҉߸Խ ϔο μ γʔέϯε൪߸ ϔο μ ฏจ ฏจ ύσ Ο ϯ ά *7 ਤ 2.6 ϒϩοΫ҉߸Խํࣜ NOTE CBC ϞʔυɺύσΟϯάɺ͓ΑͼIV ʹ͍ͭͯ͸1.4.1 અΛࢀর͍ͯͩ͘͠͞ɻ ϒϩοΫ҉߸Խํࣜ ҉߸ԽલͷϒϩοΫ௕ ͷ੔਺ഒʹͳΔΑ͏ʹ ҉߸ԽϒϩοΫͱ
 ಉ͡௕͞ $#$ϞʔυͰ҉߸Խ ͞Ε*7ͱόΠϯυ ɾ ͜ͷաఔ͸."$UIFOFODSZQUͱݺ͹ΕΔ ‣ ."$ͷಋग़ʹύσΟϯάΛؚΊͯͳ͍ͨΊɺύσΟϯάΦϥΫϧ߈ܸͷةݥੑ ɾ &ODSZQUUIFO."$ͱݺ͹ΕΔ5-4֦ுͷొ৔ ‣ ฏจσʔλͱύσΟϯάΛ࠷ॳʹ҉߸Խ͢ΔͷͰೳಈత߈ܸ͕೉͍͠ p.42ΑΓ ❶ ❷ ❸ ҉߸จ

Slide 20

Slide 20 text

ϒϩοΫ҉߸Խํࣜ 20 "&"% ೝূ෇͖҉߸ ɾ ҉߸Խͱಉ࣌ʹೝূ΋ߦ͏ ɾ ҉߸จࣗମʹೝূจؚ͕·ΕΔ ɾ φϯεͱݺ͹ΕΔҰҙͷཚ਺Λ҉߸จͱͱ΋ʹૹΔ p.43ΑΓ Ճతͳσʔλͱͯ͠ɺγʔέϯε൪߸ͱRecord ϔομ΋҉߸ԽΞϧΰϦζϜʹ౉͢ 3. φϯεͱ҉߸จΛҰॹʹૹΔ ҉߸Խ ϔο μ γʔέϯε൪߸ ϔο μ ฏจ φϯε ҉߸จ ೝূ ਤ 2.7 AEADʢೝূ෇͖҉߸ʣ AEAD ͸MAC-then-Encrypt ʹ·ͭΘΔ໰୊ΛճආͰ͖ΔͷͰɺݱࡏͷͱ͜Ζ TLS Ͱར༻Ͱ ͖Δ࠷ྑͷ҉߸Խར༻Ϟʔυͩͱ͍͑·͢ɻݱࡏͷ TLS Ͱ͸ɺೝূํࣜͷબ୒ࢶͱͯ͠ GCM

Slide 21

Slide 21 text

࠶ωΰγΤʔγϣϯ 21 ৽͍͠઀ଓͱͯ͠ϋϯυγΣΠΫΛ΍Γ௚͢ ɾ 5-4Ͱ͸ഇࢭ͞ΕΔ༧ఆɻ ɾ ηΩϡΞ͡Όͳ͍ɺ੬ऑੑΛ๊͑Δ ɾ ΫϥΠΞϯτ͸$MJFOU)FMMPɺαʔό͸)FMMP3FRVFTU͕࠶ωΰγΤʔγϣϯͷ߹ਤ ࠶ωΰγΤʔγϣϯͷར༻ྫ ɾ ΫϥΠΞϯτূ໌ॻ ‣ 8FCαΠτͷτοϓ͸ೝূͳ͠ɺ͔ͦ͜Βূ໌ॻ͕ඞཁͳϖʔδʹ༠ಋ͢Δ ͜͜Ͱ࠶ωΰγΤʔγϣϯ  ɾ ৘ใͷӅṭ ‣ ஈ֊ͰΫϥΠΞϯτূ໌ॻΛ༗ޮʹ͢Δ͜ͱͰɺճ໨ͷϋϯυγΣΠΫΛӅͤΔ ɾ ҉߸ڧ౓ͷมߋ ‣ ճ໨ͱճ໨Ͱ҉߸ڧ౓Λมߋ͢Δ ෛՙରࡦ

Slide 22

Slide 22 text

"QQMJDBUJPO%BUB "MFSU ઀ଓΛด͡Δ 22 "QQMJDBUJPO%BUBϓϩτίϧ ɾΞϓϦέʔγϣϯͷσʔλΛӡͿ ɾ5-4ʹ͓͍ͯ͸୯ͳΔσʔλͷόοϑΝ "MFSUϓϩτίϧ ɾ௨৴தʹྫ֎͕ൃੜͨ࣌͠ͷ௨஌ͷػߏ ɾ"MFSU͸ͭͷϑΟʔϧυͰදݱ͞ΕΔ ‣ "MFSU-FWFMŠXBSOJOH·ͨ͸GBUBM ଈ࣌ःஅ  ‣ "MFSU%FTDSJQUJPOŠΞϥʔτͷ಺༰Λࣔ͢ ઀ଓΛด͡Δ ɾDMPTF@OPUJGZΞϥʔτͰ஌ΒͤΔɺ͜ΕΛड͚औͬͨΒૹΓฦ͢ ɾγϟοτμ΢ϯͷϓϩτίϧΛ༻ҙ͢Δ͜ͱͰڧ੍੾அ߈ܸʹඋ͑Δ

Slide 23

Slide 23 text

ٖࣅཚ਺ੜ੒ث 23 ೚ҙͷ௕͞ͷٖࣅཚ਺ͷੜ੒ ɾ 5-4Ͱ͸೚ҙͷ௕͞ͷٖࣅཚ਺Λੜ੒͢ΔͨΊʹ13' ٖࣅཚ਺ੜ੒ث Λ༻͍Δ ɾ 13'͸Ҿ਺ͱͯ͠ɺγʔΫϨοτɾγʔυɾҰҙͳϥϕϧΛͱΔ ɾ 5-4Ҏ߱ɺ)."$ͱTIBʹجͮ͘13'ͷར༻͕ࢦఆ͞ΕΔ P_hash(Secret, seed) = HMAC_hash(secret, A(1) + 1) + HMAC_hash(secret, A(2) + 2) + HMAC_hash(secret, A(3) + 3) + A(0) = HMAC_hash(secret, seed) A(i) = HMAC_hash(secret, A(i-1)) PRF(secret, label, seed) = P_hash(secret, label + seed) 13'͸1@IBTIͷ ϥούʔ

Slide 24

Slide 24 text

ϚελʔγʔΫϨοτ伴ੜ੒ 24 ϚελʔγʔΫϨοτ ɾ ϓϦϚελγʔΫϨοτʹ13'Λט·ͤͯ࡞Δ όΠτ  ɾ 伴ަ׵ͷํ๏ʹΑͬͯϓϦϚελʔγʔΫϨοτͷ௕͕͞มΘΔ͔Β͜ͷॲཧ͕ඞཁ master_secret = PRF(pre_master_secret, “master secret”, client_random + server_random) 伴ੜ੒ ɾ 伴ૉࡐ͸ϚελʔγʔΫϨοτͱγʔυ͔Β࡞ΒΕΔ ɾ 伴ϒϩοΫΛ෼ׂ͠ɺ."$伴ɾ҉߸伴ɾ*7Λಋग़͢Δ ɾ ηογϣϯ࠶։࣌͸γʔυͷΈ৽نऔಘ͢Δ key_block = PRF(master_secret, “key expansion”, server_random + client_random)

Slide 25

Slide 25 text

҉߸εΠʔτ 25 ҉߸εΩʔϜ΍ύϥϝʔλͷ૯শ͕҉߸εΠʔτ ɾ ҉߸εΠʔτ͸໊લ͔Βத਎͕ͳΜͱͳ͘Θ͔Δ TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 伴ަ׵ ೝূ ΞϧΰϦζϜ ௕͞ Ϟʔυ ҉߸ ."$·ͨ͸13'

Slide 26

Slide 26 text

֦ு 26 ػೳΛ௥Ճ͢Δ5-4֦ு ɾ ϓϩτίϧΛमਖ਼͢Δ͜ͱͳ͘ɺ5-4ʹػೳΛ௥Ճ͢Δ࢓૊Έ ɾ 5-4֦ு͸$MJFOU)FMMP 4FSWFS)FMMPͷޙʹ഑ஔ͞ΕΔ "-1/ ɾ5-4઀ଓ্ͰΞϓϦέʔγϣϯ૚ʹҟͳΔϓϩτίϧͷ࢖༻ΛՄೳʹ͢Δ ɾ)551ͱ41%:ͷซ༻ͷΑ͏ͳ͜ͱ͕Մೳʹɺ"-1/ͷૹ৴͸ฏจ $5 ɾύϒϦοΫ$"ʹΑͬͯαʔόূ໌ॻΛશͯه࿥͠ɺ1,*ΛΑ͘͠Α͏ͱ͍͏ࢥ૝ ପԁۂઢͷར༻Մೳੑ ɾΫϥΠΞϯτͰར༻Մೳͳପԁۂઢ҉߸ΛϋϯυγΣΠΫதʹ΍ΓऔΓ ɾରԠ͍ͯ͠Δ҉߸ΛϦετԽɾପԁۂઢ্ͷ఺ͷѹॖΦϓγϣϯ ѹॖΠϚΠν

Slide 27

Slide 27 text

֦ு 27 )FBSUCFBU ɾ 6%1ͷΑ͏ͳϓϩτίϧʹLFFQBMJWFػೳͷఏڙ ɾ ਂࠁͳ੬ऑੑ )FBSUCMFFE ͕ݟ͔ͭΓ࢖ΘΕ͍ͯͳ͍ /FYU1SPUPDPM/FHPUJBUJPO ɾ41%:ͷͨΊʹ࡞ΒΕ͕ͨɺࠓ͸"-1/ʹҰຊԽ ɾൿಗԽͷͨΊʹωΰγΤʔγϣϯͯ͠Δϓϩτίϧ͕ػث͔Βݟ͑ͳ͍໰୊ ҆શͳ࠶ωΰγΤʔγϣϯ ɾҎલͷ'JOJTIFEϝοηʔδͷWFSJGZ@EBUBΛૹड'JOJTIFE͸҉߸ܦ࿏্Ͱ҆શ 4/* ɾ઀ଓ͍ͨ͠αʔόͷ໊લΛΫϥΠΞϯτ͕ࢦఆՄೳʹ͢Δ ɾಉҰϗετͷෳ਺αΠτͰ5-4Λ؆୯ʹѻ͑Δ

Slide 28

Slide 28 text

֦ு 28 ηογϣϯνέοτ ɾ ηογϣϯσʔλΛΫϥΠΞϯτଆͰ؅ཧ͢Δ࢓૊Έ ɾ $MJFOU)FMMPͷ4FTTJPO5JDLFU಺ʹؚ·ΕΔ ɾ ηογϣϯσʔλ͸αʔόͷൿີ伴Ͱ҉߸Խ͞ΕΔ ॺ໊ΞϧΰϦζϜ ɾΫϥΠΞϯτ͕ରԠ͍ͯ͠Δॺ໊ΞϧΰϦζϜͱϋογϡؔ਺ ɾͳ͔ͬͨΒαʔό͕ਪଌ͢Δ 0$41εςʔϓϧ ɾαʔό͔ΒΫϥΠΞϯτʹূ໌ॻͷࣦޮ৘ใΛૹ৴͢Δ ɾೝূہʹ໰͍߹Θͤ͢Δඞཁ͕ͳ͘ͳΔ

Slide 29

Slide 29 text

ϓϩτίϧͷݶք 29 ଞͷϨΠϠʔͷηΩϡϦςΟ͸Θ͔ΒΜ ɾ 5$1ͷϝλσʔλɾԼҐϨΠϠʔ͸ฏจͷ·· ‣ *1TFD࢖͏ͳΓͳΜͳΓ͢Δ ɾ ࠷ॳͷϋϯυγΣΠΫ͸ฏจͰ݁͹ΕΔ ‣ 26*$ͳੈͷதΛ࠲ͯ͠଴ͯ ɾ ҉߸ԽҎ߱΋࿐ग़͢Δ৘ใ͸͋Δ ‣ αϒϓϩτίϧɾ֤ϝοηʔδͷ௕͞ ‣ ϝοηʔδͷ௕͞ΛӅͤͳ͍ͳΒѹॖ͢Δ

Slide 30

Slide 30 text

ϓϩτίϧͷόʔδϣϯʹΑΔࠩҟ 30 44- ɾ ωοτεέʔϓ͕ؤுͬͯ࡞ͬͨ࠷ޙͷ44- 5-4 ɾ ΊͰͨ͘ඪ४Խ͞Ε·ͨ͠ ɾ ."$ʹඪ४Խ͞Εͨ)."$Λ࢖༻ ɾ ඪ४Խ͞Εͨ)."$ʹΑΓ13'Λنఆ ɾ ϚελʔγʔΫϨοτ͕13'ʹΑͬͯੜ੒ ɾ WFSJGZ@EBUB͕13'ʹΑͬͯੜ੒ ɾ ύσΟϯάͷϑΥʔϚοτ͕มߋ͞ΕηΩϡΞʹŠ100%-&߈ܸʜ ɾ ҉߸εΠʔτ͔Β'035&;"͕֎ΕΔ

Slide 31

Slide 31 text

ϓϩτίϧͷόʔδϣϯʹΑΔࠩҟ 31 5-4 ɾ $#$҉߸Խར༻ϞʔυͰ໌ࣔతͳ*7Λ࢖༻ɹŠ#&"45߈ܸ ɾ ύσΟϯϯά߈ܸʹର͢Δ๷ޚ ɾ 5-4֦ுΛࢀর 5-4 ɾ "&"%ɾ)."$4)"ͷαϙʔτ ɾ .%ɾTIB͕େ෯ʹ࡟আ ‣ 5-4ͰωΰγΤʔγϣϯ͞ΕͨΒ13'ͷTIB΋TIBΛ࢖͏ ‣ σδλϧॺ໊ͷ.%ɾTIBͷ૊Έ߹ΘͤΛ୯Ұͷϋογϡؔ਺ʹஔ׵ ɾ ΫϥΠΞϯτ͕ϋογϡɾॺ໊ͷΞϧΰϦζϜͷر๬Λ௨஌TJHOBUVSF@BMHPSJUIN ɾ 'JOJTIFEϝοηʔδͷWFSJGZ@EBUBͷ௕͞Λ໌ࣔతʹࢦఆՄೳʹ

Slide 32

Slide 32 text

ࢀߟ

Slide 33

Slide 33 text

ࢀߟจݙ 33 ɾ݁৓ߒ҉߸ٕज़ೖ໳ൿີͷࠃͷΞϦειϑτόϯΫΫϦΤΠςΟϒ  ɾ0QFO44-ͷ੬ऑੑ $7& Ͱ5-4ϓϩτίϧͷجૅΛֶͿ ɹIUUQEIBUFOBOFKQKPWJ ɾෆਖ਼ΞΫηεΛ๷ࢭ͢Δ44-5-4ʢʣ ɹIUUQXXXBUNBSLJUDPKQBJUBSUJDMFTOFXT@IUNM ɾ44-5-4ʢ44-ʙ5-4ʣͷϋϯυγΣΠΫΛ෮श͢Δ ɹIUUQTRJJUBDPNOJFJUFNTGEECEB