多项式RSA

最近做到的一道题，在ctfshow

# ********************
# @Author: Lazzaro
# ********************

p: 
2470567871

N: 
1932231392*x^255 + 1432733708*x^254 + 1270867914*x^253 + 1573324635*x^252 + 2378103997*x^251 + 820889786*x^250 + 762279735*x^249 + 1378353578*x^248 + 1226179520*x^247 + 657116276*x^246 + 1264717357*x^245 + 1015587392*x^244 + 849699356*x^243 + 1509168990*x^242 + 2407367106*x^241 + 873379233*x^240 + 2391647981*x^239 + 517715639*x^238 + 828941376*x^237 + 843708018*x^236 + 1526075137*x^235 + 1499291590*x^234 + 235611028*x^233 + 19615265*x^232 + 53338886*x^231 + 434434839*x^230 + 902171938*x^229 + 516444143*x^228 + 1984443642*x^227 + 966493372*x^226 + 1166227650*x^225 + 1824442929*x^224 + 930231465*x^223 + 1664522302*x^222 + 1067203343*x^221 + 28569139*x^220 + 2327926559*x^219 + 899788156*x^218 + 296985783*x^217 + 1144578716*x^216 + 340677494*x^215 + 254306901*x^214 + 766641243*x^213 + 1882320336*x^212 + 2139903463*x^211 + 1904225023*x^210 + 475412928*x^209 + 127723603*x^208 + 2015416361*x^207 + 1500078813*x^206 + 1845826007*x^205 + 797486240*x^204 + 85924125*x^203 + 1921772796*x^202 + 1322682658*x^201 + 2372929383*x^200 + 1323964787*x^199 + 1302258424*x^198 + 271875267*x^197 + 1297768962*x^196 + 2147341770*x^195 + 1665066191*x^194 + 2342921569*x^193 + 1450622685*x^192 + 1453466049*x^191 + 1105227173*x^190 + 2357717379*x^189 + 1044263540*x^188 + 697816284*x^187 + 647124526*x^186 + 1414769298*x^185 + 657373752*x^184 + 91863906*x^183 + 1095083181*x^182 + 658171402*x^181 + 75339882*x^180 + 2216678027*x^179 + 2208320155*x^178 + 1351845267*x^177 + 1740451894*x^176 + 1302531891*x^175 + 320751753*x^174 + 1303477598*x^173 + 783321123*x^172 + 1400145206*x^171 + 1379768234*x^170 + 1191445903*x^169 + 946530449*x^168 + 2008674144*x^167 + 2247371104*x^166 + 1267042416*x^165 + 1795774455*x^164 + 1976911493*x^163 + 167037165*x^162 + 1848717750*x^161 + 573072954*x^160 + 1126046031*x^159 + 376257986*x^158 + 1001726783*x^157 + 2250967824*x^156 + 2339380314*x^155 + 571922874*x^154 + 961000788*x^153 + 306686020*x^152 + 80717392*x^151 + 2454799241*x^150 + 1005427673*x^149 + 1032257735*x^148 + 593980163*x^147 + 1656568780*x^146 + 1865541316*x^145 + 2003844061*x^144 + 1265566902*x^143 + 573548790*x^142 + 494063408*x^141 + 1722266624*x^140 + 938551278*x^139 + 2284832499*x^138 + 597191613*x^137 + 476121126*x^136 + 1237943942*x^135 + 275861976*x^134 + 1603993606*x^133 + 1895285286*x^132 + 589034062*x^131 + 713986937*x^130 + 1206118526*x^129 + 311679750*x^128 + 1989860861*x^127 + 1551409650*x^126 + 2188452501*x^125 + 1175930901*x^124 + 1991529213*x^123 + 2019090583*x^122 + 215965300*x^121 + 532432639*x^120 + 1148806816*x^119 + 493362403*x^118 + 2166920790*x^117 + 185609624*x^116 + 184370704*x^115 + 2141702861*x^114 + 223551915*x^113 + 298497455*x^112 + 722376028*x^111 + 678813029*x^110 + 915121681*x^109 + 1107871854*x^108 + 1369194845*x^107 + 328165402*x^106 + 1792110161*x^105 + 798151427*x^104 + 954952187*x^103 + 471555401*x^102 + 68969853*x^101 + 453598910*x^100 + 2458706380*x^99 + 889221741*x^98 + 320515821*x^97 + 1549538476*x^96 + 909607400*x^95 + 499973742*x^94 + 552728308*x^93 + 1538610725*x^92 + 186272117*x^91 + 862153635*x^90 + 981463824*x^89 + 2400233482*x^88 + 1742475067*x^87 + 437801940*x^86 + 1504315277*x^85 + 1756497351*x^84 + 197089583*x^83 + 2082285292*x^82 + 109369793*x^81 + 2197572728*x^80 + 107235697*x^79 + 567322310*x^78 + 1755205142*x^77 + 1089091449*x^76 + 1993836978*x^75 + 2393709429*x^74 + 170647828*x^73 + 1205814501*x^72 + 2444570340*x^71 + 328372190*x^70 + 1929704306*x^69 + 717796715*x^68 + 1057597610*x^67 + 482243092*x^66 + 277530014*x^65 + 2393168828*x^64 + 12380707*x^63 + 1108646500*x^62 + 637721571*x^61 + 604983755*x^60 + 1142068056*x^59 + 1911643955*x^58 + 1713852330*x^57 + 1757273231*x^56 + 1778819295*x^55 + 957146826*x^54 + 900005615*x^53 + 521467961*x^52 + 1255707235*x^51 + 861871574*x^50 + 397953653*x^49 + 1259753202*x^48 + 471431762*x^47 + 1245956917*x^46 + 1688297180*x^45 + 1536178591*x^44 + 1833258462*x^43 + 1369087493*x^42 + 459426544*x^41 + 418389643*x^40 + 1800239647*x^39 + 2467433889*x^38 + 477713059*x^37 + 1898813986*x^36 + 2202042708*x^35 + 894088738*x^34 + 1204601190*x^33 + 1592921228*x^32 + 2234027582*x^31 + 1308900201*x^30 + 461430959*x^29 + 718926726*x^28 + 2081988029*x^27 + 1337342428*x^26 + 2039153142*x^25 + 1364177470*x^24 + 613659517*x^23 + 853968854*x^22 + 1013582418*x^21 + 1167857934*x^20 + 2014147362*x^19 + 1083466865*x^18 + 1091690302*x^17 + 302196939*x^16 + 1946675573*x^15 + 2450124113*x^14 + 1199066291*x^13 + 401889502*x^12 + 712045611*x^11 + 1850096904*x^10 + 1808400208*x^9 + 1567687877*x^8 + 2013445952*x^7 + 2435360770*x^6 + 2414019676*x^5 + 2277377050*x^4 + 2148341337*x^3 + 1073721716*x^2 + 1045363399*x + 1809685811

m^0x10001%N:  
922927962*x^254 + 1141958714*x^253 + 295409606*x^252 + 1197491798*x^251 + 2463440866*x^250 + 1671460946*x^249 + 967543123*x^248 + 119796323*x^247 + 1172760592*x^246 + 770640267*x^245 + 1093816376*x^244 + 196379610*x^243 + 2205270506*x^242 + 459693142*x^241 + 829093322*x^240 + 816440689*x^239 + 648546871*x^238 + 1533372161*x^237 + 1349964227*x^236 + 2132166634*x^235 + 403690250*x^234 + 835793319*x^233 + 2056945807*x^232 + 480459588*x^231 + 1401028924*x^230 + 2231055325*x^229 + 1716893325*x^228 + 16299164*x^227 + 1125072063*x^226 + 1903340994*x^225 + 1372971897*x^224 + 242927971*x^223 + 711296789*x^222 + 535407256*x^221 + 976773179*x^220 + 533569974*x^219 + 501041034*x^218 + 326232105*x^217 + 2248775507*x^216 + 1010397596*x^215 + 1641864795*x^214 + 1365178317*x^213 + 1038477612*x^212 + 2201213637*x^211 + 760847531*x^210 + 2072085932*x^209 + 168159257*x^208 + 70202009*x^207 + 1193933930*x^206 + 1559162272*x^205 + 1380642174*x^204 + 1296625644*x^203 + 1338288152*x^202 + 843839510*x^201 + 460174838*x^200 + 660412151*x^199 + 716865491*x^198 + 772161222*x^197 + 924177515*x^196 + 1372790342*x^195 + 320044037*x^194 + 117027412*x^193 + 814803809*x^192 + 1175035545*x^191 + 244769161*x^190 + 2116927976*x^189 + 617780431*x^188 + 342577832*x^187 + 356586691*x^186 + 695795444*x^185 + 281750528*x^184 + 133432552*x^183 + 741747447*x^182 + 2138036298*x^181 + 524386605*x^180 + 1231287380*x^179 + 1246706891*x^178 + 69277523*x^177 + 2124927225*x^176 + 2334697345*x^175 + 1769733543*x^174 + 2248037872*x^173 + 1899902290*x^172 + 409421149*x^171 + 1223261878*x^170 + 666594221*x^169 + 1795456341*x^168 + 406003299*x^167 + 992699270*x^166 + 2201384104*x^165 + 907692883*x^164 + 1667882231*x^163 + 1414341647*x^162 + 1592159752*x^161 + 28054099*x^160 + 2184618098*x^159 + 2047102725*x^158 + 103202495*x^157 + 1803852525*x^156 + 446464179*x^155 + 909116906*x^154 + 1541693644*x^153 + 166545130*x^152 + 2283548843*x^151 + 2348768005*x^150 + 71682607*x^149 + 484339546*x^148 + 669511666*x^147 + 2110974006*x^146 + 1634563992*x^145 + 1810433926*x^144 + 2388805064*x^143 + 1200258695*x^142 + 1555191384*x^141 + 363842947*x^140 + 1105757887*x^139 + 402111289*x^138 + 361094351*x^137 + 1788238752*x^136 + 2017677334*x^135 + 1506224550*x^134 + 648916609*x^133 + 2008973424*x^132 + 2452922307*x^131 + 1446527028*x^130 + 29659632*x^129 + 627390142*x^128 + 1695661760*x^127 + 734686497*x^126 + 227059690*x^125 + 1219692361*x^124 + 635166359*x^123 + 428703291*x^122 + 2334823064*x^121 + 204888978*x^120 + 1694957361*x^119 + 94211180*x^118 + 2207723563*x^117 + 872340606*x^116 + 46197669*x^115 + 710312088*x^114 + 305132032*x^113 + 1621042631*x^112 + 2023404084*x^111 + 2169254305*x^110 + 463525650*x^109 + 2349964255*x^108 + 626689949*x^107 + 2072533779*x^106 + 177264308*x^105 + 153948342*x^104 + 1992646054*x^103 + 2379817214*x^102 + 1396334187*x^101 + 2254165812*x^100 + 1300455472*x^99 + 2396842759*x^98 + 2398953180*x^97 + 88249450*x^96 + 1726340322*x^95 + 2004986735*x^94 + 2446249940*x^93 + 520126803*x^92 + 821544954*x^91 + 1177737015*x^90 + 676286546*x^89 + 1519043368*x^88 + 224894464*x^87 + 1742023262*x^86 + 142627164*x^85 + 1427710141*x^84 + 1504189919*x^83 + 688315682*x^82 + 1397842239*x^81 + 435187331*x^80 + 433176780*x^79 + 454834357*x^78 + 1046713282*x^77 + 1208458516*x^76 + 811240741*x^75 + 151611952*x^74 + 164192249*x^73 + 353336244*x^72 + 1779538914*x^71 + 1489144873*x^70 + 213140082*x^69 + 1874778522*x^68 + 908618863*x^67 + 1058334731*x^66 + 1706255211*x^65 + 708134837*x^64 + 1382118347*x^63 + 2111915733*x^62 + 1273497300*x^61 + 368639880*x^60 + 1652005004*x^59 + 1977610754*x^58 + 1412680185*x^57 + 2312775720*x^56 + 59793381*x^55 + 1345145822*x^54 + 627534850*x^53 + 2159477761*x^52 + 10450988*x^51 + 1479007796*x^50 + 2082579205*x^49 + 1158447154*x^48 + 126359830*x^47 + 393411272*x^46 + 2343384236*x^45 + 2191577465*x^44 + 1281188680*x^43 + 230049708*x^42 + 539600199*x^41 + 1711135601*x^40 + 1659775448*x^39 + 1716176055*x^38 + 904363231*x^37 + 2385749710*x^36 + 567278351*x^35 + 404199078*x^34 + 372670353*x^33 + 1286079784*x^32 + 1744355671*x^31 + 2316856064*x^30 + 2106475476*x^29 + 614988454*x^28 + 2149964943*x^27 + 1065233185*x^26 + 188130174*x^25 + 540415659*x^24 + 1031409799*x^23 + 1067085678*x^22 + 1005161755*x^21 + 249654085*x^20 + 1816791634*x^19 + 1437500292*x^18 + 448596413*x^17 + 2397497659*x^16 + 2353732701*x^15 + 2068949189*x^14 + 1826419168*x^13 + 1265366199*x^12 + 547031306*x^11 + 1016962374*x^10 + 160089486*x^9 + 2264803979*x^8 + 1081806194*x^7 + 824215340*x^6 + 497731793*x^5 + 45017166*x^4 + 317548920*x^3 + 1391127733*x^2 + 1752881284*x + 1290424106

之前也见过一道类似的没做出来，这次闲，

多项式RSA中N、M、C都是类似上面的多项式
但是加密原理和普通的RSA一样，换成多项式表达就是

$g (n) = g (p) * g (q)$
$phi=\varphi(g(n))$
$e*d\equiv1\mod phi$
$g(c)=g(m)^e \mod g(n)$
$g(m)=g(c)^d \mod g(n)$

这里补充一下欧拉函数
定义：对于欧拉函数 $\varphi(m)$ ，当m>1时， $\varphi(m)$ 表示比m小且与m互素的正整数的个数。
如果 $m$ 是素数， $\varphi(m)=m-1$
如果 $m = p * q$ ， $\varphi(m)=\varphi(p)*\varphi(q)=(p-1)*(q-1)$
如果 $m=p^e$ ，其中p是素数，e是正整数， $\varphi(m)=p^e-p^{e-1}$ ，特例e=2， $\varphi(m)=p*(p-1)$
欧拉(Euler)定理：对于任何互素的两个整数a和n，有： $a^{\varphi(n)}\equiv1\mod n$

然后继续说多项式
首先需要根据给出的p来构造以p为模，关于x的多项式

p = 2470567871
P = PolynomialRing(Zmod(p), name = 'x')
x = P.gen()

然后导入题目中已知的n、c、e

n = 1932231392*x^255 + 1432733708*x^254 + 1270867914*x^253 + 1573324635*x^252 + 2378103997*x^251 + 820889786*x^250 + 762279735*x^249 + 1378353578*x^248 + 1226179520*x^247 + 657116276*x^246 + 1264717357*x^245 + 1015587392*x^244 + 849699356*x^243 + 1509168990*x^242 + 2407367106*x^241 + 873379233*x^240 + 2391647981*x^239 + 517715639*x^238 + 828941376*x^237 + 843708018*x^236 + 1526075137*x^235 + 1499291590*x^234 + 235611028*x^233 + 19615265*x^232 + 53338886*x^231 + 434434839*x^230 + 902171938*x^229 + 516444143*x^228 + 1984443642*x^227 + 966493372*x^226 + 1166227650*x^225 + 1824442929*x^224 + 930231465*x^223 + 1664522302*x^222 + 1067203343*x^221 + 28569139*x^220 + 2327926559*x^219 + 899788156*x^218 + 296985783*x^217 + 1144578716*x^216 + 340677494*x^215 + 254306901*x^214 + 766641243*x^213 + 1882320336*x^212 + 2139903463*x^211 + 1904225023*x^210 + 475412928*x^209 + 127723603*x^208 + 2015416361*x^207 + 1500078813*x^206 + 1845826007*x^205 + 797486240*x^204 + 85924125*x^203 + 1921772796*x^202 + 1322682658*x^201 + 2372929383*x^200 + 1323964787*x^199 + 1302258424*x^198 + 271875267*x^197 + 1297768962*x^196 + 2147341770*x^195 + 1665066191*x^194 + 2342921569*x^193 + 1450622685*x^192 + 1453466049*x^191 + 1105227173*x^190 + 2357717379*x^189 + 1044263540*x^188 + 697816284*x^187 + 647124526*x^186 + 1414769298*x^185 + 657373752*x^184 + 91863906*x^183 + 1095083181*x^182 + 658171402*x^181 + 75339882*x^180 + 2216678027*x^179 + 2208320155*x^178 + 1351845267*x^177 + 1740451894*x^176 + 1302531891*x^175 + 320751753*x^174 + 1303477598*x^173 + 783321123*x^172 + 1400145206*x^171 + 1379768234*x^170 + 1191445903*x^169 + 946530449*x^168 + 2008674144*x^167 + 2247371104*x^166 + 1267042416*x^165 + 1795774455*x^164 + 1976911493*x^163 + 167037165*x^162 + 1848717750*x^161 + 573072954*x^160 + 1126046031*x^159 + 376257986*x^158 + 1001726783*x^157 + 2250967824*x^156 + 2339380314*x^155 + 571922874*x^154 + 961000788*x^153 + 306686020*x^152 + 80717392*x^151 + 2454799241*x^150 + 1005427673*x^149 + 1032257735*x^148 + 593980163*x^147 + 1656568780*x^146 + 1865541316*x^145 + 2003844061*x^144 + 1265566902*x^143 + 573548790*x^142 + 494063408*x^141 + 1722266624*x^140 + 938551278*x^139 + 2284832499*x^138 + 597191613*x^137 + 476121126*x^136 + 1237943942*x^135 + 275861976*x^134 + 1603993606*x^133 + 1895285286*x^132 + 589034062*x^131 + 713986937*x^130 + 1206118526*x^129 + 311679750*x^128 + 1989860861*x^127 + 1551409650*x^126 + 2188452501*x^125 + 1175930901*x^124 + 1991529213*x^123 + 2019090583*x^122 + 215965300*x^121 + 532432639*x^120 + 1148806816*x^119 + 493362403*x^118 + 2166920790*x^117 + 185609624*x^116 + 184370704*x^115 + 2141702861*x^114 + 223551915*x^113 + 298497455*x^112 + 722376028*x^111 + 678813029*x^110 + 915121681*x^109 + 1107871854*x^108 + 1369194845*x^107 + 328165402*x^106 + 1792110161*x^105 + 798151427*x^104 + 954952187*x^103 + 471555401*x^102 + 68969853*x^101 + 453598910*x^100 + 2458706380*x^99 + 889221741*x^98 + 320515821*x^97 + 1549538476*x^96 + 909607400*x^95 + 499973742*x^94 + 552728308*x^93 + 1538610725*x^92 + 186272117*x^91 + 862153635*x^90 + 981463824*x^89 + 2400233482*x^88 + 1742475067*x^87 + 437801940*x^86 + 1504315277*x^85 + 1756497351*x^84 + 197089583*x^83 + 2082285292*x^82 + 109369793*x^81 + 2197572728*x^80 + 107235697*x^79 + 567322310*x^78 + 1755205142*x^77 + 1089091449*x^76 + 1993836978*x^75 + 2393709429*x^74 + 170647828*x^73 + 1205814501*x^72 + 2444570340*x^71 + 328372190*x^70 + 1929704306*x^69 + 717796715*x^68 + 1057597610*x^67 + 482243092*x^66 + 277530014*x^65 + 2393168828*x^64 + 12380707*x^63 + 1108646500*x^62 + 637721571*x^61 + 604983755*x^60 + 1142068056*x^59 + 1911643955*x^58 + 1713852330*x^57 + 1757273231*x^56 + 1778819295*x^55 + 957146826*x^54 + 900005615*x^53 + 521467961*x^52 + 1255707235*x^51 + 861871574*x^50 + 397953653*x^49 + 1259753202*x^48 + 471431762*x^47 + 1245956917*x^46 + 1688297180*x^45 + 1536178591*x^44 + 1833258462*x^43 + 1369087493*x^42 + 459426544*x^41 + 418389643*x^40 + 1800239647*x^39 + 2467433889*x^38 + 477713059*x^37 + 1898813986*x^36 + 2202042708*x^35 + 894088738*x^34 + 1204601190*x^33 + 1592921228*x^32 + 2234027582*x^31 + 1308900201*x^30 + 461430959*x^29 + 718926726*x^28 + 2081988029*x^27 + 1337342428*x^26 + 2039153142*x^25 + 1364177470*x^24 + 613659517*x^23 + 853968854*x^22 + 1013582418*x^21 + 1167857934*x^20 + 2014147362*x^19 + 1083466865*x^18 + 1091690302*x^17 + 302196939*x^16 + 1946675573*x^15 + 2450124113*x^14 + 1199066291*x^13 + 401889502*x^12 + 712045611*x^11 + 1850096904*x^10 + 1808400208*x^9 + 1567687877*x^8 + 2013445952*x^7 + 2435360770*x^6 + 2414019676*x^5 + 2277377050*x^4 + 2148341337*x^3 + 1073721716*x^2 + 1045363399*x + 1809685811
c = 922927962*x^254 + 1141958714*x^253 + 295409606*x^252 + 1197491798*x^251 + 2463440866*x^250 + 1671460946*x^249 + 967543123*x^248 + 119796323*x^247 + 1172760592*x^246 + 770640267*x^245 + 1093816376*x^244 + 196379610*x^243 + 2205270506*x^242 + 459693142*x^241 + 829093322*x^240 + 816440689*x^239 + 648546871*x^238 + 1533372161*x^237 + 1349964227*x^236 + 2132166634*x^235 + 403690250*x^234 + 835793319*x^233 + 2056945807*x^232 + 480459588*x^231 + 1401028924*x^230 + 2231055325*x^229 + 1716893325*x^228 + 16299164*x^227 + 1125072063*x^226 + 1903340994*x^225 + 1372971897*x^224 + 242927971*x^223 + 711296789*x^222 + 535407256*x^221 + 976773179*x^220 + 533569974*x^219 + 501041034*x^218 + 326232105*x^217 + 2248775507*x^216 + 1010397596*x^215 + 1641864795*x^214 + 1365178317*x^213 + 1038477612*x^212 + 2201213637*x^211 + 760847531*x^210 + 2072085932*x^209 + 168159257*x^208 + 70202009*x^207 + 1193933930*x^206 + 1559162272*x^205 + 1380642174*x^204 + 1296625644*x^203 + 1338288152*x^202 + 843839510*x^201 + 460174838*x^200 + 660412151*x^199 + 716865491*x^198 + 772161222*x^197 + 924177515*x^196 + 1372790342*x^195 + 320044037*x^194 + 117027412*x^193 + 814803809*x^192 + 1175035545*x^191 + 244769161*x^190 + 2116927976*x^189 + 617780431*x^188 + 342577832*x^187 + 356586691*x^186 + 695795444*x^185 + 281750528*x^184 + 133432552*x^183 + 741747447*x^182 + 2138036298*x^181 + 524386605*x^180 + 1231287380*x^179 + 1246706891*x^178 + 69277523*x^177 + 2124927225*x^176 + 2334697345*x^175 + 1769733543*x^174 + 2248037872*x^173 + 1899902290*x^172 + 409421149*x^171 + 1223261878*x^170 + 666594221*x^169 + 1795456341*x^168 + 406003299*x^167 + 992699270*x^166 + 2201384104*x^165 + 907692883*x^164 + 1667882231*x^163 + 1414341647*x^162 + 1592159752*x^161 + 28054099*x^160 + 2184618098*x^159 + 2047102725*x^158 + 103202495*x^157 + 1803852525*x^156 + 446464179*x^155 + 909116906*x^154 + 1541693644*x^153 + 166545130*x^152 + 2283548843*x^151 + 2348768005*x^150 + 71682607*x^149 + 484339546*x^148 + 669511666*x^147 + 2110974006*x^146 + 1634563992*x^145 + 1810433926*x^144 + 2388805064*x^143 + 1200258695*x^142 + 1555191384*x^141 + 363842947*x^140 + 1105757887*x^139 + 402111289*x^138 + 361094351*x^137 + 1788238752*x^136 + 2017677334*x^135 + 1506224550*x^134 + 648916609*x^133 + 2008973424*x^132 + 2452922307*x^131 + 1446527028*x^130 + 29659632*x^129 + 627390142*x^128 + 1695661760*x^127 + 734686497*x^126 + 227059690*x^125 + 1219692361*x^124 + 635166359*x^123 + 428703291*x^122 + 2334823064*x^121 + 204888978*x^120 + 1694957361*x^119 + 94211180*x^118 + 2207723563*x^117 + 872340606*x^116 + 46197669*x^115 + 710312088*x^114 + 305132032*x^113 + 1621042631*x^112 + 2023404084*x^111 + 2169254305*x^110 + 463525650*x^109 + 2349964255*x^108 + 626689949*x^107 + 2072533779*x^106 + 177264308*x^105 + 153948342*x^104 + 1992646054*x^103 + 2379817214*x^102 + 1396334187*x^101 + 2254165812*x^100 + 1300455472*x^99 + 2396842759*x^98 + 2398953180*x^97 + 88249450*x^96 + 1726340322*x^95 + 2004986735*x^94 + 2446249940*x^93 + 520126803*x^92 + 821544954*x^91 + 1177737015*x^90 + 676286546*x^89 + 1519043368*x^88 + 224894464*x^87 + 1742023262*x^86 + 142627164*x^85 + 1427710141*x^84 + 1504189919*x^83 + 688315682*x^82 + 1397842239*x^81 + 435187331*x^80 + 433176780*x^79 + 454834357*x^78 + 1046713282*x^77 + 1208458516*x^76 + 811240741*x^75 + 151611952*x^74 + 164192249*x^73 + 353336244*x^72 + 1779538914*x^71 + 1489144873*x^70 + 213140082*x^69 + 1874778522*x^68 + 908618863*x^67 + 1058334731*x^66 + 1706255211*x^65 + 708134837*x^64 + 1382118347*x^63 + 2111915733*x^62 + 1273497300*x^61 + 368639880*x^60 + 1652005004*x^59 + 1977610754*x^58 + 1412680185*x^57 + 2312775720*x^56 + 59793381*x^55 + 1345145822*x^54 + 627534850*x^53 + 2159477761*x^52 + 10450988*x^51 + 1479007796*x^50 + 2082579205*x^49 + 1158447154*x^48 + 126359830*x^47 + 393411272*x^46 + 2343384236*x^45 + 2191577465*x^44 + 1281188680*x^43 + 230049708*x^42 + 539600199*x^41 + 1711135601*x^40 + 1659775448*x^39 + 1716176055*x^38 + 904363231*x^37 + 2385749710*x^36 + 567278351*x^35 + 404199078*x^34 + 372670353*x^33 + 1286079784*x^32 + 1744355671*x^31 + 2316856064*x^30 + 2106475476*x^29 + 614988454*x^28 + 2149964943*x^27 + 1065233185*x^26 + 188130174*x^25 + 540415659*x^24 + 1031409799*x^23 + 1067085678*x^22 + 1005161755*x^21 + 249654085*x^20 + 1816791634*x^19 + 1437500292*x^18 + 448596413*x^17 + 2397497659*x^16 + 2353732701*x^15 + 2068949189*x^14 + 1826419168*x^13 + 1265366199*x^12 + 547031306*x^11 + 1016962374*x^10 + 160089486*x^9 + 2264803979*x^8 + 1081806194*x^7 + 824215340*x^6 + 497731793*x^5 + 45017166*x^4 + 317548920*x^3 + 1391127733*x^2 + 1752881284*x + 1290424106
e = 0x10001

然后就是RSA解密

#分解N
q1, q2 = n.factor()
q1, q2 = q1[0], q2[0]

#求φ，注意求法，
phi = (p**q1.degree() - 1) * (p**q2.degree() - 1)
assert gcd(e, phi) == 1
d = inverse_mod(e, phi)
m = pow(c,d,n)

#取多项式系数
flag = bytes(m.coefficients())
print("Flag: ", flag.decode())

代码参考：https://blog.csdn.net/m0_49109277/article/details/118603921

然后大佬还给出了另一个代码

#脚本2
#Sage
#已知p=2,n,e,c
p =
P = PolynomialRing(GF(p), name = 'x')
x = P.gen()
e =
n =
R.<a> = GF(2^2049)
c = []

q1, q2 = n.factor()
q1, q2 = q1[0], q2[0]

phi = (p**q1.degree() - 1) * (p**q2.degree() - 1)
assert gcd(e, phi) == 1
d = inverse_mod(e, phi)

ans = ''
for cc in c:
    cc = P(R.fetch_int(cc))
    m = pow(cc,d,n)
    m = R(P(m)).integer_representation()
    print(m)
    ans += chr(m)
print(ans)

还有一道类似的例题

#!/usr/bin/env sage
# coding=utf-8

from pubkey import P, n, e
from secret import flag
from os import urandom

R.<a> = GF(2^2049)

def encrypt(m):
    global n
    assert len(m) <= 256
    m_int = Integer(m.encode('hex'), 16)
    m_poly = P(R.fetch_int(m_int)) 
    c_poly = pow(m_poly, e, n)
    c_int = R(c_poly).integer_representation() 
    c = format(c_int, '0256x').decode('hex')
    return c

if __name__ == '__main__':
    ptext = flag + os.urandom(256-len(flag))
    ctext = encrypt(ptext)
    with open('flag.enc', 'wb') as f:
        f.write(ctext)

先对密文进行还原

file_object = open('./flag.enc','rb')
file_context = file_object.read()
x=int(file_context.encode('hex'),16)
print x

然后

p,q = n.factor()
phi = (p-1)*(q-1)
phi_int=R(P(phi)).integer_representation()#phi为多项式，将phi转为整数
d = inveser_mod(e,phi_int)

c_poly=P(R.fetch_int(c))
phi_int=(2^1227-1)*(2^821-1)
d=inverse_mod(e_int,phi_int)
flag=pow(c_poly,d,n)
flag_int=R(P(flag)).integer_representation()

这道题代码参考:https://xz.aliyun.com/t/4545
相关知识点参考：https://aluvion.gitee.io/file/0CTF2019/RSA.pdf

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