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Add an AES 256 implementation.
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
This commit is contained in:
NIIBE Yutaka
parent
e26445c687
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137
misc/gen_rijndael_t_table.py
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137
misc/gen_rijndael_t_table.py
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@ -0,0 +1,137 @@
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#
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# gen_rijndael_t_table.py - Generate Rijndael T-Table
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#
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# Non-Copyright (CC0) 2020 Free Software Initiative of Japan
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# Author: NIIBE Yutaka <gniibe@fsij.org>
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#
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# This file is made available under the Creative Commons CC0 1.0
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# Universal Public Domain Dedication.
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#
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# To the extent possible under law, the person who associated CC0 with
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# this work has waived all copyright and related or neighboring rights
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# to this work.
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#
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#
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# Generate Rijindael T-Table (the first one) in the format
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# of Mbed TLS (originally callled PolarSSL, by Paul Bakker).
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#
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# Rijndael uses GF(2^8) with a irreducible polynomial:
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#
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# m(x) = x^8 + x^4 + x^3 + x + 1
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#
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# A point in the field is represented by 8-bit binary.
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# 0x1b represents a lower part of m(x), x^4 + x^3 + x + 1
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m_irreducible = 0x1b
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# The constant
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C = 0x63
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# Function XTIME - Multiplication by x
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#
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# Given a polynomial A of GF(2)[x], compute a polynomial multiplied by x,
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# modulo m(x).
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def xtime(a):
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global m_irreducible
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if a & 0x80:
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return ((a & 0x7f) << 1) ^ m_irreducible
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else:
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return a << 1
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# Function GMULT - Galore field multiplication
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#
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# Given polynomials A, B of GF(2)[x], compute a polynomial A * B,
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# modulo m(x).
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def gmult(a,b):
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r = 0
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for i in range(8):
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r = r ^ ((b & 0x01) * a)
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b = b >> 1
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a = xtime(a)
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return r
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# Function INV - Multiplicative inverse
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#
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# Given polynomials A of GF(2)[x], compute its multiplicative inverse.
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#
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# Extended to have defined value at A=0, returning 0.
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#
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# Note about the implementation:
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#
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# Brute force appoarch finding an inverse is more efficient. Further,
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# for efficiency, using two tables of exp and log (with any good base
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# like 3, 5, 6...) to compute exp(log(1) - log(a)) is much better,
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# when called many times.
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#
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def inv(a):
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r = 1
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for i in range(254): # 254 = 2^8 - 2
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r = gmult(r,a)
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return r
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# Circular shift operation
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def rotate(a,n):
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return ((a << n) & 0xff) | (a >> (8 - n))
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def rijndael_affine_transform(v):
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global C
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return v ^ rotate(v,1) ^ rotate(v,2) ^ rotate(v,3) ^ rotate(v,4) ^ C
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def sbox_value(i):
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return rijndael_affine_transform(inv(i))
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def print_t_table_value(i,x):
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y = xtime(x)
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z = x ^ y
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punct = "" if i==255 else ", \\\n " if i % 4 == 3 else ", "
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print("V(","%02X," % z,"%02X," % x,"%02X," % x,"%02X)" % y,
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punct, sep='', end='')
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if __name__ == '__main__':
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#
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# Usage:
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# $ python3 gen_rijndael_t_table.py
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#
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# Usage with args, replacing the irreducible and the constant:
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# $ python3 gen_rijndael_t_table.py 1b 63
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#
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# Usage to generate Rcon
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# $ python3 gen_rijndael_t_table.py 'Rcon[10]'
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#
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# $ python3 gen_rijndael_t_table.py 1b 63 'Rcon[10]'
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#
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name_rcon = None
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import sys
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if len(sys.argv) == 2:
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name_rcon = sys.argv[1]
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elif len(sys.argv) >= 3:
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m_irreducible = int(sys.argv[1],16)
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C = int(sys.argv[2],16)
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if len(sys.argv) == 4:
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name_rcon = sys.argv[3]
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if name_rcon:
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n_rcon = int(name_rcon[name_rcon.index('[')+1:name_rcon.index(']')])
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print("static const uint32_t %s =\n{" % name_rcon)
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x = 1
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print(" ", end='')
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for i in range(n_rcon):
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punct = "\n" if i==n_rcon-1 else ",\n " if i % 4 == 3 else ", "
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print("0x%08X" % x, punct, sep='', end='')
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x = xtime(x)
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print("};")
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exit(0)
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# Note: I just want to use list comprehension of Python, though not needed
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S_box=[sbox_value(i) for i in range(256)]
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print("#define FT \\")
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print(" ", end='')
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for i in range(256):
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x = S_box[i]
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print_t_table_value(i,x)
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print("")
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@ -8,6 +8,7 @@ CHOPSTX = ../chopstx
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CSRC = main.c \
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CSRC = main.c \
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usb_desc.c usb_ctrl.c \
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usb_desc.c usb_ctrl.c \
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usb-ccid.c openpgp.c ac.c openpgp-do.c flash.c \
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usb-ccid.c openpgp.c ac.c openpgp-do.c flash.c \
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aes.c \
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bn.c mod.c \
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bn.c mod.c \
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modp256k1.c jpc_p256k1.c ec_p256k1.c call-ec_p256k1.c \
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modp256k1.c jpc_p256k1.c ec_p256k1.c call-ec_p256k1.c \
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mod25638.c ecc-ed25519.c ecc-mont.c sha512.c \
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mod25638.c ecc-ed25519.c ecc-mont.c sha512.c \
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@ -17,14 +18,6 @@ CSRC = main.c \
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INCDIR =
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INCDIR =
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CRYPTDIR = ../polarssl
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CRYPTSRCDIR = $(CRYPTDIR)/library
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CRYPTINCDIR = $(CRYPTDIR)/include
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CRYPTSRC = $(CRYPTSRCDIR)/aes.c
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CSRC += $(CRYPTSRC)
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INCDIR += $(CRYPTINCDIR)
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include config.mk
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include config.mk
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USE_SYS = yes
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USE_SYS = yes
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66
src/aes-t-table.c.in
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66
src/aes-t-table.c.in
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@ -0,0 +1,66 @@
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/* Generated by ../misc/gen_rijndael_t_table.py */
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#define FT \
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V(A5,63,63,C6), V(84,7C,7C,F8), V(99,77,77,EE), V(8D,7B,7B,F6), \
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V(0D,F2,F2,FF), V(BD,6B,6B,D6), V(B1,6F,6F,DE), V(54,C5,C5,91), \
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V(50,30,30,60), V(03,01,01,02), V(A9,67,67,CE), V(7D,2B,2B,56), \
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V(19,FE,FE,E7), V(62,D7,D7,B5), V(E6,AB,AB,4D), V(9A,76,76,EC), \
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V(45,CA,CA,8F), V(9D,82,82,1F), V(40,C9,C9,89), V(87,7D,7D,FA), \
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V(15,FA,FA,EF), V(EB,59,59,B2), V(C9,47,47,8E), V(0B,F0,F0,FB), \
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V(EC,AD,AD,41), V(67,D4,D4,B3), V(FD,A2,A2,5F), V(EA,AF,AF,45), \
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V(BF,9C,9C,23), V(F7,A4,A4,53), V(96,72,72,E4), V(5B,C0,C0,9B), \
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V(C2,B7,B7,75), V(1C,FD,FD,E1), V(AE,93,93,3D), V(6A,26,26,4C), \
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V(5A,36,36,6C), V(41,3F,3F,7E), V(02,F7,F7,F5), V(4F,CC,CC,83), \
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V(5C,34,34,68), V(F4,A5,A5,51), V(34,E5,E5,D1), V(08,F1,F1,F9), \
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V(93,71,71,E2), V(73,D8,D8,AB), V(53,31,31,62), V(3F,15,15,2A), \
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V(0C,04,04,08), V(52,C7,C7,95), V(65,23,23,46), V(5E,C3,C3,9D), \
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V(28,18,18,30), V(A1,96,96,37), V(0F,05,05,0A), V(B5,9A,9A,2F), \
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V(09,07,07,0E), V(36,12,12,24), V(9B,80,80,1B), V(3D,E2,E2,DF), \
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V(26,EB,EB,CD), V(69,27,27,4E), V(CD,B2,B2,7F), V(9F,75,75,EA), \
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V(1B,09,09,12), V(9E,83,83,1D), V(74,2C,2C,58), V(2E,1A,1A,34), \
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V(2D,1B,1B,36), V(B2,6E,6E,DC), V(EE,5A,5A,B4), V(FB,A0,A0,5B), \
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V(F6,52,52,A4), V(4D,3B,3B,76), V(61,D6,D6,B7), V(CE,B3,B3,7D), \
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V(7B,29,29,52), V(3E,E3,E3,DD), V(71,2F,2F,5E), V(97,84,84,13), \
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V(F5,53,53,A6), V(68,D1,D1,B9), V(00,00,00,00), V(2C,ED,ED,C1), \
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V(60,20,20,40), V(1F,FC,FC,E3), V(C8,B1,B1,79), V(ED,5B,5B,B6), \
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V(BE,6A,6A,D4), V(46,CB,CB,8D), V(D9,BE,BE,67), V(4B,39,39,72), \
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V(DE,4A,4A,94), V(D4,4C,4C,98), V(E8,58,58,B0), V(4A,CF,CF,85), \
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V(6B,D0,D0,BB), V(2A,EF,EF,C5), V(E5,AA,AA,4F), V(16,FB,FB,ED), \
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V(C5,43,43,86), V(D7,4D,4D,9A), V(55,33,33,66), V(94,85,85,11), \
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V(CF,45,45,8A), V(10,F9,F9,E9), V(06,02,02,04), V(81,7F,7F,FE), \
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V(F0,50,50,A0), V(44,3C,3C,78), V(BA,9F,9F,25), V(E3,A8,A8,4B), \
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V(F3,51,51,A2), V(FE,A3,A3,5D), V(C0,40,40,80), V(8A,8F,8F,05), \
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V(AD,92,92,3F), V(BC,9D,9D,21), V(48,38,38,70), V(04,F5,F5,F1), \
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V(DF,BC,BC,63), V(C1,B6,B6,77), V(75,DA,DA,AF), V(63,21,21,42), \
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V(30,10,10,20), V(1A,FF,FF,E5), V(0E,F3,F3,FD), V(6D,D2,D2,BF), \
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V(4C,CD,CD,81), V(14,0C,0C,18), V(35,13,13,26), V(2F,EC,EC,C3), \
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V(E1,5F,5F,BE), V(A2,97,97,35), V(CC,44,44,88), V(39,17,17,2E), \
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V(57,C4,C4,93), V(F2,A7,A7,55), V(82,7E,7E,FC), V(47,3D,3D,7A), \
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V(AC,64,64,C8), V(E7,5D,5D,BA), V(2B,19,19,32), V(95,73,73,E6), \
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V(A0,60,60,C0), V(98,81,81,19), V(D1,4F,4F,9E), V(7F,DC,DC,A3), \
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V(66,22,22,44), V(7E,2A,2A,54), V(AB,90,90,3B), V(83,88,88,0B), \
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V(CA,46,46,8C), V(29,EE,EE,C7), V(D3,B8,B8,6B), V(3C,14,14,28), \
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V(79,DE,DE,A7), V(E2,5E,5E,BC), V(1D,0B,0B,16), V(76,DB,DB,AD), \
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V(3B,E0,E0,DB), V(56,32,32,64), V(4E,3A,3A,74), V(1E,0A,0A,14), \
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V(DB,49,49,92), V(0A,06,06,0C), V(6C,24,24,48), V(E4,5C,5C,B8), \
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V(5D,C2,C2,9F), V(6E,D3,D3,BD), V(EF,AC,AC,43), V(A6,62,62,C4), \
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V(A8,91,91,39), V(A4,95,95,31), V(37,E4,E4,D3), V(8B,79,79,F2), \
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V(32,E7,E7,D5), V(43,C8,C8,8B), V(59,37,37,6E), V(B7,6D,6D,DA), \
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V(8C,8D,8D,01), V(64,D5,D5,B1), V(D2,4E,4E,9C), V(E0,A9,A9,49), \
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V(B4,6C,6C,D8), V(FA,56,56,AC), V(07,F4,F4,F3), V(25,EA,EA,CF), \
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V(AF,65,65,CA), V(8E,7A,7A,F4), V(E9,AE,AE,47), V(18,08,08,10), \
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V(D5,BA,BA,6F), V(88,78,78,F0), V(6F,25,25,4A), V(72,2E,2E,5C), \
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V(24,1C,1C,38), V(F1,A6,A6,57), V(C7,B4,B4,73), V(51,C6,C6,97), \
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V(23,E8,E8,CB), V(7C,DD,DD,A1), V(9C,74,74,E8), V(21,1F,1F,3E), \
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V(DD,4B,4B,96), V(DC,BD,BD,61), V(86,8B,8B,0D), V(85,8A,8A,0F), \
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V(90,70,70,E0), V(42,3E,3E,7C), V(C4,B5,B5,71), V(AA,66,66,CC), \
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V(D8,48,48,90), V(05,03,03,06), V(01,F6,F6,F7), V(12,0E,0E,1C), \
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V(A3,61,61,C2), V(5F,35,35,6A), V(F9,57,57,AE), V(D0,B9,B9,69), \
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V(91,86,86,17), V(58,C1,C1,99), V(27,1D,1D,3A), V(B9,9E,9E,27), \
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V(38,E1,E1,D9), V(13,F8,F8,EB), V(B3,98,98,2B), V(33,11,11,22), \
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V(BB,69,69,D2), V(70,D9,D9,A9), V(89,8E,8E,07), V(A7,94,94,33), \
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V(B6,9B,9B,2D), V(22,1E,1E,3C), V(92,87,87,15), V(20,E9,E9,C9), \
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V(49,CE,CE,87), V(FF,55,55,AA), V(78,28,28,50), V(7A,DF,DF,A5), \
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V(8F,8C,8C,03), V(F8,A1,A1,59), V(80,89,89,09), V(17,0D,0D,1A), \
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V(DA,BF,BF,65), V(31,E6,E6,D7), V(C6,42,42,84), V(B8,68,68,D0), \
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V(C3,41,41,82), V(B0,99,99,29), V(77,2D,2D,5A), V(11,0F,0F,1E), \
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V(CB,B0,B0,7B), V(FC,54,54,A8), V(D6,BB,BB,6D), V(3A,16,16,2C)
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236
src/aes.c
Normal file
236
src/aes.c
Normal file
@ -0,0 +1,236 @@
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/*
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* aes.c - AES256 for Gnuk
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*
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* Copyright (C) 2020 Free Software Initiative of Japan
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* Author: NIIBE Yutaka <gniibe@fsij.org>
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*
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* This file is a part of Gnuk, a GnuPG USB Token implementation.
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*
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* Gnuk is free software: you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* Gnuk is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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||||||
|
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
|
||||||
|
* License for more details.
|
||||||
|
*
|
||||||
|
* You should have received a copy of the GNU General Public License
|
||||||
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||||
|
*
|
||||||
|
*
|
||||||
|
* This is an implementation using four T tables (little endian),
|
||||||
|
* keysize fixed for AES-256.
|
||||||
|
*
|
||||||
|
*/
|
||||||
|
|
||||||
|
/*
|
||||||
|
* For AES-256:
|
||||||
|
*
|
||||||
|
* Block size in bit = 128, Nb = 4 (= 128 / 32) (in 32-bit word)
|
||||||
|
* Key size in bit = 256, Nk = 8 (= 256 / 32) (in 32-bit word)
|
||||||
|
* Number of round Nr = 14
|
||||||
|
*
|
||||||
|
* Contextsize = Nb * (Nr + 1) = 60 (in 32-bit word)
|
||||||
|
*/
|
||||||
|
#define Nr 14
|
||||||
|
#define Nk (AES_KEY_SIZE/4)
|
||||||
|
|
||||||
|
#include <string.h>
|
||||||
|
#include "aes.h"
|
||||||
|
|
||||||
|
static uint32_t
|
||||||
|
get_uint32_le (const unsigned char *b, unsigned int i)
|
||||||
|
{
|
||||||
|
return ( ((uint32_t)b[i ] )
|
||||||
|
| ((uint32_t)b[i + 1] << 8)
|
||||||
|
| ((uint32_t)b[i + 2] << 16)
|
||||||
|
| ((uint32_t)b[i + 3] << 24));
|
||||||
|
}
|
||||||
|
|
||||||
|
static void
|
||||||
|
put_uint32_le (unsigned char *b, unsigned int i, uint32_t n)
|
||||||
|
{
|
||||||
|
b[i ] = (unsigned char) ((n) );
|
||||||
|
b[i + 1] = (unsigned char) ((n) >> 8);
|
||||||
|
b[i + 2] = (unsigned char) ((n) >> 16);
|
||||||
|
b[i + 3] = (unsigned char) ((n) >> 24);
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
/* Forward table */
|
||||||
|
#include "aes-t-table.c.in"
|
||||||
|
|
||||||
|
#define V(a,b,c,d) 0x##a##b##c##d
|
||||||
|
/* Note that We expose FT0 table. */
|
||||||
|
const uint32_t FT0[256] = { FT };
|
||||||
|
#undef V
|
||||||
|
|
||||||
|
#define V(a,b,c,d) 0x##b##c##d##a
|
||||||
|
static const uint32_t FT1[256] = { FT };
|
||||||
|
#undef V
|
||||||
|
|
||||||
|
#define V(a,b,c,d) 0x##c##d##a##b
|
||||||
|
static const uint32_t FT2[256] = { FT };
|
||||||
|
#undef V
|
||||||
|
|
||||||
|
#define V(a,b,c,d) 0x##d##a##b##c
|
||||||
|
static const uint32_t FT3[256] = { FT };
|
||||||
|
#undef V
|
||||||
|
|
||||||
|
#undef FT
|
||||||
|
|
||||||
|
/* Round constants */
|
||||||
|
/*
|
||||||
|
* Note: For AES-256, since (AES_CONTEXT_SIZE / Nk) = 7, we have no
|
||||||
|
* carry-over in xtime computation for round constants, thus, the
|
||||||
|
* irreducible polynomial doesn't matter at all.
|
||||||
|
*/
|
||||||
|
#define Rcon(i) (1 << i)
|
||||||
|
|
||||||
|
|
||||||
|
static void
|
||||||
|
key_expansion_step_0 (uint32_t *RK, unsigned int i)
|
||||||
|
{
|
||||||
|
RK[8] = RK[0] ^ (FT3[( RK[7] >> 8 ) & 0xff] & 0x000000ff)
|
||||||
|
^ (FT0[( RK[7] >> 16 ) & 0Xff] & 0x0000ff00)
|
||||||
|
^ (FT1[( RK[7] >> 24 ) & 0Xff] & 0x00ff0000)
|
||||||
|
^ (FT2[( RK[7] ) & 0xff] & 0xff000000)
|
||||||
|
^ Rcon(i);
|
||||||
|
RK[9] = RK[1] ^ RK[8];
|
||||||
|
RK[10] = RK[2] ^ RK[9];
|
||||||
|
RK[11] = RK[3] ^ RK[10];
|
||||||
|
}
|
||||||
|
|
||||||
|
static void
|
||||||
|
key_expansion_step_1 (uint32_t *RK)
|
||||||
|
{
|
||||||
|
RK[12] = RK[4] ^ (FT3[( RK[11] ) & 0xff] & 0x000000ff)
|
||||||
|
^ (FT0[( RK[11] >> 8 ) & 0xff] & 0x0000ff00)
|
||||||
|
^ (FT1[( RK[11] >> 16 ) & 0xff] & 0x00ff0000)
|
||||||
|
^ (FT2[( RK[11] >> 24 ) & 0xff] & 0xff000000);
|
||||||
|
RK[13] = RK[5] ^ RK[12];
|
||||||
|
RK[14] = RK[6] ^ RK[13];
|
||||||
|
RK[15] = RK[7] ^ RK[14];
|
||||||
|
}
|
||||||
|
|
||||||
|
/*
|
||||||
|
* AES key setup
|
||||||
|
*/
|
||||||
|
void
|
||||||
|
aes_set_key (aes_context *ctx, const unsigned char key[AES_KEY_SIZE])
|
||||||
|
{
|
||||||
|
unsigned int i;
|
||||||
|
uint32_t *RK = ctx->rk;
|
||||||
|
|
||||||
|
/* Nk times */
|
||||||
|
RK[0] = get_uint32_le (key, 0);
|
||||||
|
RK[1] = get_uint32_le (key, 4);
|
||||||
|
RK[2] = get_uint32_le (key, 8);
|
||||||
|
RK[3] = get_uint32_le (key, 12);
|
||||||
|
RK[4] = get_uint32_le (key, 16);
|
||||||
|
RK[5] = get_uint32_le (key, 20);
|
||||||
|
RK[6] = get_uint32_le (key, 24);
|
||||||
|
RK[7] = get_uint32_le (key, 28);
|
||||||
|
|
||||||
|
for (i = 0; i < (AES_CONTEXT_SIZE / Nk) - 1; i++)
|
||||||
|
{
|
||||||
|
key_expansion_step_0 (RK, i);
|
||||||
|
key_expansion_step_1 (RK);
|
||||||
|
RK += Nk;
|
||||||
|
}
|
||||||
|
|
||||||
|
key_expansion_step_0 (RK, i);
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
static uint32_t
|
||||||
|
round_calc_step (uint32_t y0, uint32_t y1, uint32_t y2, uint32_t y3)
|
||||||
|
{
|
||||||
|
uint32_t x;
|
||||||
|
|
||||||
|
x = FT0[( y0 ) & 0xff]
|
||||||
|
^ FT1[( y1 >> 8 ) & 0xff]
|
||||||
|
^ FT2[( y2 >> 16 ) & 0xff]
|
||||||
|
^ FT3[( y3 >> 24 ) & 0xff];
|
||||||
|
return x;
|
||||||
|
}
|
||||||
|
|
||||||
|
#define ROUND(X0,X1,X2,X3,Y0,Y1,Y2,Y3) \
|
||||||
|
X0 = round_calc_step (Y0, Y1, Y2, Y3) ^ *RK++; \
|
||||||
|
X1 = round_calc_step (Y1, Y2, Y3, Y0) ^ *RK++; \
|
||||||
|
X2 = round_calc_step (Y2, Y3, Y0, Y1) ^ *RK++; \
|
||||||
|
X3 = round_calc_step (Y3, Y0, Y1, Y2) ^ *RK++
|
||||||
|
|
||||||
|
static uint32_t
|
||||||
|
last_round_calc_step (uint32_t y0, uint32_t y1, uint32_t y2, uint32_t y3)
|
||||||
|
{
|
||||||
|
uint32_t x;
|
||||||
|
|
||||||
|
x = (FT3[( y0 ) & 0xff] & 0x000000ff)
|
||||||
|
^ (FT0[( y1 >> 8 ) & 0xff] & 0x0000ff00)
|
||||||
|
^ (FT1[( y2 >> 16 ) & 0xff] & 0x00ff0000)
|
||||||
|
^ (FT2[( y3 >> 24 ) & 0xff] & 0xff000000);
|
||||||
|
return x;
|
||||||
|
}
|
||||||
|
|
||||||
|
#define LAST_ROUND(X0,X1,X2,X3,Y0,Y1,Y2,Y3) \
|
||||||
|
X0 = last_round_calc_step (Y0, Y1, Y2, Y3) ^ *RK++; \
|
||||||
|
X1 = last_round_calc_step (Y1, Y2, Y3, Y0) ^ *RK++; \
|
||||||
|
X2 = last_round_calc_step (Y2, Y3, Y0, Y1) ^ *RK++; \
|
||||||
|
X3 = last_round_calc_step (Y3, Y0, Y1, Y2) ^ *RK++
|
||||||
|
|
||||||
|
/*
|
||||||
|
* AES block encryption
|
||||||
|
*/
|
||||||
|
void
|
||||||
|
aes_encrypt (const aes_context *ctx,
|
||||||
|
unsigned char output[AES_BLOCK_SIZE],
|
||||||
|
const unsigned char input[AES_BLOCK_SIZE])
|
||||||
|
{
|
||||||
|
uint32_t X0, X1, X2, X3, Y0, Y1, Y2, Y3;
|
||||||
|
const uint32_t *RK = ctx->rk;
|
||||||
|
|
||||||
|
/* Nb times */
|
||||||
|
X0 = get_uint32_le (input, 0) ^ *RK++;
|
||||||
|
X1 = get_uint32_le (input, 4) ^ *RK++;
|
||||||
|
X2 = get_uint32_le (input, 8) ^ *RK++;
|
||||||
|
X3 = get_uint32_le (input, 12) ^ *RK++;
|
||||||
|
|
||||||
|
/* Nr-1 times */
|
||||||
|
ROUND (Y0, Y1, Y2, Y3, X0, X1, X2, X3);
|
||||||
|
ROUND (X0, X1, X2, X3, Y0, Y1, Y2, Y3);
|
||||||
|
ROUND (Y0, Y1, Y2, Y3, X0, X1, X2, X3);
|
||||||
|
ROUND (X0, X1, X2, X3, Y0, Y1, Y2, Y3);
|
||||||
|
ROUND (Y0, Y1, Y2, Y3, X0, X1, X2, X3);
|
||||||
|
ROUND (X0, X1, X2, X3, Y0, Y1, Y2, Y3);
|
||||||
|
ROUND (Y0, Y1, Y2, Y3, X0, X1, X2, X3);
|
||||||
|
ROUND (X0, X1, X2, X3, Y0, Y1, Y2, Y3);
|
||||||
|
ROUND (Y0, Y1, Y2, Y3, X0, X1, X2, X3);
|
||||||
|
ROUND (X0, X1, X2, X3, Y0, Y1, Y2, Y3);
|
||||||
|
ROUND (Y0, Y1, Y2, Y3, X0, X1, X2, X3);
|
||||||
|
ROUND (X0, X1, X2, X3, Y0, Y1, Y2, Y3);
|
||||||
|
ROUND (Y0, Y1, Y2, Y3, X0, X1, X2, X3);
|
||||||
|
|
||||||
|
/* And, then */
|
||||||
|
LAST_ROUND (X0, X1, X2, X3, Y0, Y1, Y2, Y3);
|
||||||
|
|
||||||
|
/* Nb times */
|
||||||
|
put_uint32_le (output, 0, X0);
|
||||||
|
put_uint32_le (output, 4, X1);
|
||||||
|
put_uint32_le (output, 8, X2);
|
||||||
|
put_uint32_le (output, 12, X3);
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
/*
|
||||||
|
* AES key teardown
|
||||||
|
*/
|
||||||
|
void
|
||||||
|
aes_clear_key (aes_context *ctx)
|
||||||
|
{
|
||||||
|
memset (ctx->rk, 0, sizeof ctx->rk);
|
||||||
|
/* to compiler: no removal of memset above, please */
|
||||||
|
asm ("" : : "m" (ctx->rk) : "memory");
|
||||||
|
}
|
||||||
53
src/aes.h
Normal file
53
src/aes.h
Normal file
@ -0,0 +1,53 @@
|
|||||||
|
#include <stdint.h>
|
||||||
|
|
||||||
|
#define AES_BLOCK_SIZE 16 /* in byte */
|
||||||
|
|
||||||
|
/*
|
||||||
|
* For AES-256:
|
||||||
|
*
|
||||||
|
* Block size in bit = 128, Nb = 4 (= 128 / 32) (in 32-bit word)
|
||||||
|
* Key size in bit = 256, Nk = 8 (= 256 / 32) (in 32-bit word)
|
||||||
|
* Number of round Nr = 14
|
||||||
|
*
|
||||||
|
* Contextsize = Nb * (Nr + 1) = 60 (in 32-bit word)
|
||||||
|
*/
|
||||||
|
#define AES_KEY_SIZE 32 /* in byte */
|
||||||
|
#define AES_CONTEXT_SIZE 60 /* in word */
|
||||||
|
|
||||||
|
/**
|
||||||
|
* AES context structure
|
||||||
|
*
|
||||||
|
*/
|
||||||
|
typedef struct
|
||||||
|
{
|
||||||
|
uint32_t rk[AES_CONTEXT_SIZE]; /*!< AES round keys (60-words) */
|
||||||
|
} aes_context;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* AES key setup
|
||||||
|
*
|
||||||
|
* @param ctx AES context
|
||||||
|
* @param key key
|
||||||
|
*
|
||||||
|
*/
|
||||||
|
void aes_set_key (aes_context *ctx, const unsigned char key[AES_KEY_SIZE]);
|
||||||
|
|
||||||
|
/**
|
||||||
|
* AES block encryption
|
||||||
|
*
|
||||||
|
* @param ctx AES context
|
||||||
|
* @param output output block
|
||||||
|
* @param input input block
|
||||||
|
*
|
||||||
|
*/
|
||||||
|
void aes_encrypt (const aes_context *ctx,
|
||||||
|
unsigned char output[AES_BLOCK_SIZE],
|
||||||
|
const unsigned char input[AES_BLOCK_SIZE]);
|
||||||
|
|
||||||
|
/**
|
||||||
|
* AES key teardown
|
||||||
|
*
|
||||||
|
* @param ctx AES context
|
||||||
|
*
|
||||||
|
*/
|
||||||
|
void aes_clear_key (aes_context *ctx);
|
||||||
Loading…
Reference in New Issue
Block a user