def delete_share(cls, sid):
from os import remove
from models import File
share = cls.get_by(id_ = sid)
fid = share.fid
if share:
db.session.delete(share)
db.session.commit()
f = File.get_by(fileid = fid)
remove(shared_path + str(f.uid) + '/' + f.sha256)
def verify_share():
fid = request.args.get('fid')
nonce = request.args.get('nonce')
# 查询分享数据库中是否有该文件
f = Share.get_by(fid = fid, nonce = nonce)
if(not f):
return 404
else:
f = File.get_by(fileid = fid)
fname = f.filename
uid = f.uid
name = User.get_by(usrid = uid).usrname
return render_template('unlock.html', form=EnsureForm(fid=fid, nonce=nonce), \
fname=fname, name=name)
def download_shared():
from config import shared_path
from flask import make_response
from collections import OrderedDict
import unicodedata
from werkzeug.urls import url_quote
form = EnsureForm()
fid = form.fid.data
nonce = form.nonce.data
sharekey = form.sharekey.data
f = Share.get_by(fid=fid, nonce=nonce)
if f is None:
return 404
else:
# 验证分享码是否正确
sharekey = bytes.fromhex(sharekey)
saved = f.sharekey
success = argon2.verify(sharekey, saved)
if not success:
flash('分享码不正确！')
return redirect('/msg_box')
# 用分享码解密获得对称密钥
enc_key = f.enc_key
sym_key = secret.symmetric_decrypt(sharekey, enc_key)
f = File.get_by(fileid=fid)
uid = f.uid
hash_value = f.sha256
PublicKey = User.get_by(usrid=uid).pubkey
# 对称解密
path = shared_path + str(uid) + '/' + hash_value
with open(path, 'rb') as f_:
content = f_.read()
decrypted_content = secret.symmetric_decrypt(sym_key, content)
response = make_response(decrypted_content)
filename = f.filename
filenames = OrderedDict()
try:
filename = filename.encode('latin-1')
except UnicodeEncodeError:
filenames['filename'] = unicodedata.normalize('NFKD', filename).encode('latin-1', 'ignore')
filenames['filename*']:"UTF-8''{}".format(url_quote(filename))
else:
filenames['filename'] = filename
response.headers.set('Content-Disposition', 'attachment', **filenames)
return response
def decrypt_and_encrypt(cls, fid, user, sym_key):
from .file import File
from .online_user import OnlineUser
import secret
# 获取私钥解密获得对称密钥
usr = OnlineUser.query.filter(OnlineUser.usrid == user.usrid).first()
Pk = usr.Pk
enc_key = secret.decrypt(Pk, user.symkey)
# 查询、读取本地存储的加密文件
f = File.get_by(fileid = fid)
hash_value = f.sha256
with open(storage_path + str(user.usrid) + '/' + hash_value, 'rb') as f:
content = f.read()
# 解密文件
content = secret.symmetric_decrypt(enc_key, content)
# 用私钥签名
sig = secret.sign(Pk, content)
# 用新的会话密钥加密文件
new_content = secret.symmetric_encrypt(sym_key, content)
# 写入 shared_path
user_id = str(user.usrid) + '/'
head = shared_path + user_id
full_path = head + hash_value
if not path.exists(head):
if not path.exists(shared_path):
mkdir(shared_path)
mkdir(head)
# 判断文件是否存在
# 分享文件夹要写入签名
if not path.exists(full_path):
with open(full_path, 'wb') as f:
f.write(new_content)
with open(full_path + '.sig', 'wb') as f:
f.write(sig)
def post_share():
import random, string
from config import domain_name, sy_public_key
user = current_user
fid = request.form['fid']
choice = request.form['choice']
nonce = ''.join(random.SystemRandom().choice(string.ascii_letters + string.digits) for _ in range(8))
ShareKey = secret.new_symmetric_key()
sym_key = secret.new_symmetric_key()
# 先对称解密再用新的分享密钥对称加密
Share.decrypt_and_encrypt(fid, user, sym_key)
# 分享码对对称密钥加密
enc_key = secret.symmetric_encrypt(ShareKey, sym_key)
# 慢速哈希分享码
hashShareKey = argon2.using(rounds=256, memory_cost=1024).hash(ShareKey)
# 使用服务器公钥加密分享码
enc_ShareKey = secret.encrypt(bytes.fromhex(sy_public_key), ShareKey)
sid = Share.add_share(fid, hashShareKey, enc_ShareKey, nonce, enc_key)
# 向指定用户发送分享消息
choice = choice.split(',')
for u in choice:
Message.create_msg(User.get_by(mail=u).usrid, user.usrname, sid, File.get_by(fileid=fid).filename)
return '分享成功！'