nortti
/
qrcrypt
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Compress qrcrypt.py further

This commit is contained in:
Juhani Krekelä 2020-06-25 14:58:27 +03:00
parent d3c57278f4
commit 5c5ff31d0e
1 changed files with 3 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
qrcrypt.py
View File

@ -8,8 +8,7 @@ add=lambda x,y:x+y&0xffffffff
rl=lambda x,n:x<<n&0xffffffff|x>>32-n
def qr(a,b,c,d):a=add(a,b);d^=a;d=rl(d,16);c=add(c,d);b^=c;b=rl(b,12);a=add(a,b);d^=a;d=rl(d,8);c=add(c,d);b^=c;b=rl(b,7);return a,b,c,d
def ccb(k,c,n,f):
s=[0x61707865,857760878,0x79622d32,0x6b206574,q(k[:4]),q(k[4:8]),q(k[8:12]),q(k[12:16]),q(k[16:20]),q(k[20:24]),q(k[24:28]),q(k[28:]),c,q(n[:4]),q(n[4:8]),q(n[8:])]
o=s[:]
s=[0x61707865,857760878,0x79622d32,0x6b206574,q(k[:4]),q(k[4:8]),q(k[8:12]),q(k[12:16]),q(k[16:20]),q(k[20:24]),q(k[24:28]),q(k[28:]),c,q(n[:4]),q(n[4:8]),q(n[8:])];o=s[:]
if f:o=[0]*16
def x(a,b,c,d):s[a],s[b],s[c],s[d]=qr(s[a],s[b],s[c],s[d])
for _ in range(10):x(0,4,8,12);x(1,5,9,13);x(2,6,10,14);x(3,7,11,15);x(0,5,10,15);x(1,6,11,12);x(2,7,8,13);x(3,4,9,14)
@ -24,8 +23,7 @@ def hcc20(k,n):s=ccb(k,q(n[:4]),n[4:],1);return s[:16]+s[48:]
p=2**255-19
def cs(s,a,b):d=-s&((1<<255)-1)&(a^b);a=a^d;b=b^d;return a,b
def x(k,u):
k=bytearray(k);k[0]&=248;k[31]&=127;k[31]|=64;k=q(k);u=q(u[:-1]+bytes([u[-1]&127]))
x=u;y=1;z=0;w=u;v=1;s=0
k=bytearray(k);k[0]&=248;k[31]&=127;k[31]|=64;k=q(k);u=q(u[:-1]+bytes([u[-1]&127]));x=u;y=1;z=0;w=u;v=1;s=0
for t in range(254,-1,-1):kt=(k>>t)&1;s^=kt;y,w=cs(s,y,w);z,v=cs(s,z,v);s=kt;A=(y+z)%p;AA=pow(A,2,p);B=(y-z)%p;BB=pow(B,2,p);E=(AA-BB)%p;C=(w+v)%p;D=(w-v)%p;DA=(D*A)%p;CB=(C*B)%p;w=pow((DA+CB)%p,2,p);v=(x*pow((DA-CB)%p,2,p))%p;y=(AA*BB)%p;z=(E*((AA+(121665*E)%p)%p)%p)%p
y,w=cs(s,y,w);z,v=cs(s,z,v);u=(y*pow(z,p-2,p))%p;return bytes(u>>i&255 for i in range(0,255,8))
pubkey=lambda sk:x(sk,b'\x09'+b'\x00'*31)
@ -46,8 +44,7 @@ if __name__ == '__main__':
esk,epk=kg();rss=ecdh(bytes.fromhex(sys.argv[2]),esk);k=hcc20(rss,b'\x00'*24);o=os.urandom(24);k=hcc20(k, o[:16]);n=b'\x00'*4+o[16:];c=bytes(cc20(k,n,sys.stdin.buffer.read()));sys.stdout.buffer.write(epk+o+c+tag(k,n,c))
elif sys.argv[1] == '-D':
with open(sys.argv[2],'rb')as f:sk=f.read()
e=sys.stdin.buffer.read();epk=e[:32];n=e[32:56];rss=ecdh(epk,sk);k=hcc20(rss,b'\x00'*24)
k=hcc20(k, n[:16]);n=b'\x00'*4+n[16:];c=e[56:-16]
e=sys.stdin.buffer.read();epk=e[:32];n=e[32:56];rss=ecdh(epk,sk);k=hcc20(rss,b'\x00'*24);k=hcc20(k, n[:16]);n=b'\x00'*4+n[16:];c=e[56:-16]
if not secrets.compare_digest(e[-16:],tag(k,n,c)):print('Error: auth fail',file=sys.stderr);sys.exit(1)
else:sys.stdout.buffer.write(bytes(cc20(k,n,c)))
else:us()