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@0verflowme
Created October 25, 2020 18:34
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{
"cells": [
{
"cell_type": "code",
"execution_count": 1,
"metadata": {},
"outputs": [],
"source": [
"n = 3283820208958447696987943374117448908009765357285654693385347327161990683145362435055078968569512096812028089118865534433123727617331619214412173257331161\n",
"p = 34387544593670505224894952205499074005031928791959611454481093888481277920639\n",
"q = 95494466027181231798633086231116363926111790946014452380632032637864163116199\n",
"e = 65537\n",
"c = 2152534604028570372634288477962037445130495144236447333908131330331177601915631781056255815304219841064038378099612028528380520661613873180982330559507116"
]
},
{
"cell_type": "code",
"execution_count": 2,
"metadata": {},
"outputs": [],
"source": [
"#https://crypto.stackexchange.com/questions/81949/how-to-compute-m-value-from-rsa-if-phin-is-not-relative-prime-with-the-e/81966#81966\n",
"lmb = (p-1)*(q-1)/gcd(p-1,q-1)"
]
},
{
"cell_type": "code",
"execution_count": 3,
"metadata": {},
"outputs": [
{
"data": {
"text/plain": [
"25053177662682512908646591803999640722109383686205156578614731580343856776669915872289379410352080265907742753566186968532170785613443597417381233626"
]
},
"execution_count": 3,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"lmb/e"
]
},
{
"cell_type": "code",
"execution_count": 4,
"metadata": {},
"outputs": [
{
"data": {
"text/plain": [
"610603001254786950117204016100094851174682771252096629718770045663657708853546673840012894001567171172542663753238859651358189495264776579202830986736744"
]
},
"execution_count": 4,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"pow(2,_,n)"
]
},
{
"cell_type": "code",
"execution_count": 5,
"metadata": {},
"outputs": [],
"source": [
"L = _"
]
},
{
"cell_type": "code",
"execution_count": 6,
"metadata": {},
"outputs": [],
"source": [
"d = (e^-1)%(lmb/e)"
]
},
{
"cell_type": "code",
"execution_count": 7,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"flag{thanks_so_much_for_helping_me_with_these_primitive_primes}\n"
]
}
],
"source": [
"from Crypto.Util.number import *\n",
"for i in range(1,e):\n",
"# print(c,d,L,i,n)\n",
" flag = (pow(c,d,n)*pow(L,i,n))%n\n",
" p = long_to_bytes(flag).decode('latin1')\n",
" if \"flag\" in p:\n",
" print(p)\n",
" break"
]
},
{
"cell_type": "code",
"execution_count": null,
"metadata": {},
"outputs": [],
"source": []
}
],
"metadata": {
"kernelspec": {
"display_name": "SageMath 9.0",
"language": "sage",
"name": "sagemath"
},
"language_info": {
"codemirror_mode": {
"name": "ipython",
"version": 3
},
"file_extension": ".py",
"mimetype": "text/x-python",
"name": "python",
"nbconvert_exporter": "python",
"pygments_lexer": "ipython3",
"version": "3.8.5"
}
},
"nbformat": 4,
"nbformat_minor": 4
}
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