Diffie-Hellman algorithm: kugadzwa

Kunenge vanhu vashomanana nhasi, vachishandisa mashoko pamusoro kusachengeteka kukurukura migero, fungidzira zvakanga algorithm Diffie-Hellman. Kutaura zvazviri, vakawanda havanzwisisi uye vanoda. Zvisinei, vanoshandisa makombiyuta, saka kutaura, zvikuru kuziva kuti kunzwisisa uku haakuvadzi. Kunyanya, mushonga Exchange Diffie-Hellman anogona kubatsira vanoshandisa vari kufarira nyaya mashoko kuchengeteka uye cryptography.

Chii nzira Diffie-Hellman?

Kana isu kutaura nyaya algorithm pacharo, asi pasina kupinda hwokugadzira uye akarongeka mashoko, tinogona kutsanangura rive nzira encryption uye Decryption mashoko zvitange uye akagamuchira pakati maviri kana kupfuura vanoshandisa kombiyuta kana zvimwe gadziriro hunobatanidza kupanana umboo nokushandiswa kunoitwa kudzivirirwa kukurukurirana mugero.

Sezvo zviri pachena, pasina kudzivirira chiteshi kunomisa kana kuchinja mafaira ari muitiro kuparadzira nokugamuchira, uye zvebhinya anogona. Zvisinei, chinokosha kuparadzirwa Diffie-Hellman kuti kuwana wokushandura uye kugamuchira mashoko zvokuti tampering panobviswa zvinenge chose. In ichi ruzivo kutaurirana vakanyorwa pamwe kukurukurirana chiteshi (pasina dziviriro zvayo) anova akachengeteka kana vaviri vanoshandisa kiyi chete.

prehistory

The algorithm Diffie-Hellman wakatangwa kumashure muna 1976 nyika. creators Its kuva Uitfrid Diffie uye Martin Hellman, uyo pakutsvakurudza yake vakachengeteka uye yakavimbika date encryption nzira inobva basa Ralph Merkle, uyo akakurukura dzinonzi pachena pfungwa Kuparadzirwa hurongwa.

Asi kana Merkle yakatanga chete yokungotaura hwaro, Diffie uye Hellman akapa kuruzhinji rinoshanda kugadzirisa dambudziko iri.

The nyore tsanangudzo

Chaizvoizvo, bvunzo pazvikanganiso cryptographic encryption ruzivo zvino kushamiswa nyanzvi dzakawanda mumunda uyu. ciphers Anthology rinoti kunosanganisira chaizvo kare. Musimboti yose muitiro iri nechokwadi kuti pane mativi maviri, e-no, kana nedzimwe kupanana umboo vachibatsirwa ekombiyuta. Asi kudzivirira kunoitwa nenzira yakadaro kuti Diffie-Hellman algorithm pachayo kunoda kuti Decryption chikuru anozivikanwa kuti mapato maviri (kutumira nokutambira). Kana izvi zvachose hakukoshi ndeupi wavo tanga kwokutanga kurongwa nhamba (pfungwa iyi anofanira kutsanangura kana tichifunga anokosha kukarukureta Masvomhu).

Nzira encrypting mashoko vekare nguva

Kuti izvozvo zvakajeka, tinoona kuti chinonyanya chinyakare nzira encrypt mashoko ari Somuenzaniso, chiperengo haina kuruboshwe, sezvo tsika dzakawanda mumanyoro uye kodzero kuruboshwe. Saizvozvowo, unogona kushandisa nyore uye yaitsiva earufabheti ari mashoko. Somuenzaniso, shoko anochinja tsamba yechipiri kune wekutanga, wechina - wechitatu uye zvichingodaro. The chaizvo chete Gwaro iri pamberi chive maturo zvachose. Zvisinei, uyo akanyora bhuku code, maererano munhu ane kuverenga, mune chii kuti zvinofanira kuiswa zvimwe vatambi. Izvi zvinonzi kiyi.

Ona kuti vakawanda vachiri undeciphered ndima uye muzvinyorwa sevaSumer vekare uye vaEgipita ecuneiform havasi kunzwisisa crypto-vaongorori chete nemhaka yokuti havazivi kuti amutse aida kutevedzana pazvinhu.

Uye kwatiri - the Diffie-Hellman musiyano wezvinyorwa anotora kuti Decryption Chinokosha achizivikanwa vashoma vanoshandisa. Zvisinei, uye pano zvakafanira kuti kuchengetedza, nokuti chipingaidzo iri kwemashoko encrypted mashoko kwakadai kunogona chibharo kumapati wechitatu, kana vachaita kugadzirisa kuzvitsinhanisa kana yaitsiva vatambi.

It anoenda pasina vachiti kuti ikozvino kune cryptosystem simba zvakakwana kwakavakirwa algorithms akadai AES, asi havazivi kupa vimbiso izere kudzivirira kugura yechitatu-party Data.

Zvakanaka, zvino isu kutarisa zvikuru encryption hurongwa, ayo anoshanda kushanda uye mwero kudzivirirwa.

Diffie-Hellman algorithm: kugadzwa

The algorithm akasikwa kuti nechokwadi kwete chete toga mashoko panguva kupararira mumwe webato kune vamwe, asi kuti zvakachengeteka kuvabvisa pamusoro chionekeso. Nehasha kutaura, kwakadaro Kupfuudzwa gadziriro anofanira nechokwadi kudzivirira chizere zvichiita migero zvose dzokukurukurirana.

Yeuka, panguva Second World War, kana ungwaru dzose batana nyika remuSamoa andivhimira encryption muchina unonzi "kutadza kunzwisisa", naro wokushandura encoded mashoko Morse romutemo. Pamusoro pazvo, kugona kugadzirisa Cipher hapana, kunyange nzira yatiri kutaura nezvake, "mazhinji" vakadzidza cryptography. Chete pashure kubatwa kwayo rwaiwanikwa kiyi achiongorora zvaive mashoko akatumwa German romugungwa.

Diffie-Hellman algorithm: muchidimbu

Saka, algorithm kunosanganisira kushandiswa zvishoma zvinokosha pfungwa. Tomboti tine nyore nyaya, kana mapato maviri (inodzidzisa) varipo ari papi. We kureva navo sezvo A uye B.

Vanoshandisa maviri nhamba X uye Y, havasi zvakavanzika ichi kukurukurirana mugero, kudzora handover. The Chaizvoizvo yose mubvunzo mamota pasi, kusika kwavo nokuda mumwe mhando itsva kukosha kuti vachava chinokosha. Asi! Chokutanga vandine ari kushandisa hombe wehurumende nhamba, uye wechipiri - nguva dzose integer (divisible), asi kudzika kuitira kupfuura kutanga.

Sezvingatarisirwa, vanozvishandisa vanobvumirana kuti nhamba iyi chakavanzika. Zvisinei, nokuti nzira iri kuchengeteka, nhamba mbiri inogona kuva mapati vanofarira kuvazivisa uye nezvimwe. Ndokusaka vanhu vari chete mashoko vakatsinhanisa kiyi muchivande kuti decrypt shoko.

Dzinokosha zvokuimba kuti pakuverenga kiyi

Zvinofungirwa kuti Diffie-Hellman rinoreva kwegadziriro inonzi symmetric encryption, iro paiva mishumo asymmetric Cipher. Zvisinei, kana tiri funga zvikuru zvinoumba kukarukureta kiyi hondo mapati, kuti kuyeuka pane nemasvomhu.

Saka, Somuenzaniso, mumwe nomumwe subscribers zvinowanisa anongoitika nhamba uye b. Vanoziva pachine zvinokosheswa X uye ja, izvo zvinogona kunyange "vasonanidza" iri runodiwa software.

Paakatuma kana kugamuchira shoko ivavo rinotengeswa nevaridzi A computes kiyi kukosha, kubvira nzira ^A = X ^munhu Mod Y, apo wechipiri anoshandisa ibatanidzo B = X ^b Mod Y, uchiteverwa kutumwa decrypted kiyi yokutanga user. Iri ndiro danho rokutanga.

Zvino ngatiti kuti bato chechitatu hanya ine panguva yayo achigona zvose vakaverenga netsika A uye B. All chete, harigoni kupindira muitiro tama data, nekuti danho rechipiri kuziva sei kuverenga chimwe chinhu chinokosha.

Kubva apa Masvomhu, unogona kugara vanhuwo anokosha kukarukureta. Kana kutarira Diffie-Hellman muenzaniso vangatarira seizvi:

1) anoti yokutanga rinotengeswa nevaridzi kiyi kwakavakirwa X parutivi nzira ^{B ane Mod Y = X AB Mod} Y;

2) Chechipiri, inobva kwokutanga nhamba and uye vakagadzirira maererano zvakarukwa dzakati sarudzo B, rinotsanangura chinoita kubva kumbova parameter ^{A: B Mod Y = X} sq Mod and.

Sezvaunogona kuona, rokupedzisira tsika kunyange apo permutation madhigirii rienderane. Saka, decoding kuti mashoko nemapoka acho ipfupi, sezvo vachiti, kune chimwe dhinomineta.

Vulnerability panguva Kupindira ari date kutapurirana muitiro

Sezvo ungatarisira, wechitatu bato kupindira iri dziripowo. Zvisinei, muchiitiko ichi ndiyo pakutanga kutaridzwa nhamba 10 ^100, kana kunyange ^10.300.

It anoenda pasina vachiti hapana nhasi kuti pave pasiwedhi kana kuwana bumbiro emagetsi kuziva nhamba pachayo handigoni (kunze kuti kwokutanga uye chokupedzisira uye kwete zvokungoitawo nzira kuti kupindira mune hutachiwana mugadziriro). Zvaizoda nguva zvokuti upenyu panyika ichaguma. Zvisinei, Makwanza zvakadaro kuchengeteka hurongwa uchiripo.

Kakawanda vari chokuita nokuziva discrete logarithm. Kana zivo yakadaro iri kutsemuka ari Diffie-Hellman algorithm inogona (asi kutanga uye yokupedzisira parameters sezvataurwa pamusoro apa). Chimwe chinhu ndechokuti ive ruzivo yakadaro dzakabatana.

Kushandisa algorithm nokuda Java papuratifomu

Diffie-Hellman algorithm rinoshandiswa Java bedzi kukwidza se "nemhosva-Server".

Nemamwe mashoko, Server iri kudzamara Connect yeGmail.END_STRONG michina. Kana kuti kubatana chinoitwa, pane mabasa ari algorithm pamusoro achitsvaka paruzhinji kana private anokosha, uye ipapo anoishandisa vanogona uoinde kune mabasa ose uye mashoko ose Server pachayo. Dzimwe nguva izvi ndezvechokwadi kunyange munzvimbo Mobile gadziriro, zvisinei, ava vanhu vashoma chaizvo kuziva, zvikuru kuti nevarikutonga chikamu nemabasa ari asingaoneki muoti muchimiro executable mumanyoro.

Kushandisa algorithm nokuda pachikuva C (+ / ++)

Kana kutarira Diffie-Hellman ari «C» (+ / ++), saka hapana mvere. Chokwadi ndechokuti dzimwe nguva pane dambudziko kana akawanda basa pamwe Masvomhu pachake zvirongwa mutauro chokuita zvinoyangarara pfungwa. Ndokusaka nekumisa integer kukosha, kana apo kuedza rounding (kunyange Exponentiation), pangava nematambudziko panguva batanidza nguva. Kunyanya nezvezvitadzo kushandiswa Int ishande.

Zvisinei, zvinokosha achiteerera kune vamwe executable zvinoriumba iyo, sezvo mutemo, ndivo basa makirasi, zvakafanana Exponentiation kana attachable GMP chokuita raibhurari.

Modern encryption algorithms

Zvinonzi vaidavira kuti Diffie-Hellman achiri kurova, hapana anogona. Kutaura zvazviri, ndiye akashanda sehwaro kuti chidzoke akadai anozivikanwa gadziriro kudzivirira mumunda date encryption sezvo AES128 uye AES256.

Zvisinei, sezvo tsika inoratidza pasinei Kuwanikwa nhamba chaihwoihwo haina panoonekwa nomunhu, vakawanda mugadziriro mhando iyi kushandiswa chete kukosha rokutanga dhazeni (pasisina), asi algorithm pachayo kunoreva nhamba miriyoni nguva yakawanda.

panzvimbo imwe epilogue

Kazhinji, zvichida, atova pachena chii chinoumba ino uye chii ayo algorithmic zvinoriumba. It chete unoramba kuwedzera kuti vachinzwisisa zvinogona kukuru zvokuti kwazvo anenge hapana anoshandisa.

Ukuwo, uye munjodzi ari algorithm zvakajeka zvakakwana. Nditongerei woga: zvechokwadi, nyora purogiramu compute discrete logarithms, chero musiki kwayo kuwana kwete chete kune kutanga parameters wakasiyiwa anoishandisa, asiwo kune veruzhinji kiyi, riri zvakapararira munyika encryption uye Decryption gadziriro.

In nyore Kana zvakakwana kuti kugadzwa executable pakati Java-applet, izvo zvinogona kushandiswa kunyange Mobile kukurukurirana. Chokwadi, inodzidzisa uye asingazivi nezvazvo, asi mashoko aro achakwanisa kushandisa munhu.