// ------------------------------------------------------------------------- // Copyright (c) 2001, Dr Brian Gladman < >, Worcester, UK. // All rights reserved. // // LICENSE TERMS // // The free distribution and use of this software in both source and binary // form is allowed (with or without changes) provided that: // // 1. distributions of this source code include the above copyright // notice, this list of conditions and the following disclaimer// // // 2. distributions in binary form include the above copyright // notice, this list of conditions and the following disclaimer // in the documentation and/or other associated materials// // // 3. the copyright holder's name is not used to endorse products // built using this software without specific written permission. // // // ALTERNATIVELY, provided that this notice is retained in full, this product // may be distributed under the terms of the GNU General Public License (GPL), // in which case the provisions of the GPL apply INSTEAD OF those given above. // // Copyright (c) 2004 Linus Torvalds <torvalds@osdl.org> // Copyright (c) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com> // DISCLAIMER // // This software is provided 'as is' with no explicit or implied warranties // in respect of its properties including, but not limited to, correctness // and fitness for purpose. // ------------------------------------------------------------------------- // Issue Date: 29/07/2002 .file "aes-i586-asm.S" .text // aes_rval aes_enc_blk(const unsigned char in_blk[], unsigned char out_blk[], const aes_ctx cx[1])// // aes_rval aes_dec_blk(const unsigned char in_blk[], unsigned char out_blk[], const aes_ctx cx[1])// #define tlen 1024 // length of each of 4 'xor' arrays (256 32-bit words) // offsets to parameters with one register pushed onto stack #define in_blk 8 // input byte array address parameter #define out_blk 12 // output byte array address parameter #define ctx 16 // AES context structure // offsets in context structure #define ekey 0 // encryption key schedule base address #define nrnd 256 // number of rounds #define dkey 260 // decryption key schedule base address // register mapping for encrypt and decrypt subroutines #define r0 eax #define r1 ebx #define r2 ecx #define r3 edx #define r4 esi #define r5 edi #define eaxl al #define eaxh ah #define ebxl bl #define ebxh bh #define ecxl cl #define ecxh ch #define edxl dl #define edxh dh #define _h(reg) reg##h #define h(reg) _h(reg) #define _l(reg) reg##l #define l(reg) _l(reg) // This macro takes a 32-bit word representing a column and uses // each of its four bytes to index into four tables of 256 32-bit // words to obtain values that are then xored into the appropriate // output registers r0, r1, r4 or r5. // Parameters: // table table base address // %1 out_state[0] // %2 out_state[1] // %3 out_state[2] // %4 out_state[3] // idx input register for the round (destroyed) // tmp scratch register for the round // sched key schedule #define do_col(table, a1,a2,a3,a4, idx, tmp) \ movzx %l(idx),%tmp; \ xor table(,%tmp,4),%a1; \ movzx %h(idx),%tmp; \ shr $16,%idx; \ xor table+tlen(,%tmp,4),%a2; \ movzx %l(idx),%tmp; \ movzx %h(idx),%idx; \ xor table+2*tlen(,%tmp,4),%a3; \ xor table+3*tlen(,%idx,4),%a4; // initialise output registers from the key schedule // NB1: original value of a3 is in idx on exit // NB2: original values of a1,a2,a4 aren't used #define do_fcol(table, a1,a2,a3,a4, idx, tmp, sched) \ mov 0 sched,%a1; \ movzx %l(idx),%tmp; \ mov 12 sched,%a2; \ xor table(,%tmp,4),%a1; \ mov 4 sched,%a4; \ movzx %h(idx),%tmp; \ shr $16,%idx; \ xor table+tlen(,%tmp,4),%a2; \ movzx %l(idx),%tmp; \ movzx %h(idx),%idx; \ xor table+3*tlen(,%idx,4),%a4; \ mov %a3,%idx; \ mov 8 sched,%a3; \ xor table+2*tlen(,%tmp,4),%a3; // initialise output registers from the key schedule // NB1: original value of a3 is in idx on exit // NB2: original values of a1,a2,a4 aren't used #define do_icol(table, a1,a2,a3,a4, idx, tmp, sched) \ mov 0 sched,%a1; \ movzx %l(idx),%tmp; \ mov 4 sched,%a2; \ xor table(,%tmp,4),%a1; \ mov 12 sched,%a4; \ movzx %h(idx),%tmp; \ shr $16,%idx; \ xor table+tlen(,%tmp,4),%a2; \ movzx %l(idx),%tmp; \ movzx %h(idx),%idx; \ xor table+3*tlen(,%idx,4),%a4; \ mov %a3,%idx; \ mov 8 sched,%a3; \ xor table+2*tlen(,%tmp,4),%a3; // original Gladman had conditional saves to MMX regs. #define save(a1, a2) \ mov %a2,4*a1(%esp) #define restore(a1, a2) \ mov 4*a2(%esp),%a1 // These macros perform a forward encryption cycle. They are entered with // the first previous round column values in r0,r1,r4,r5 and // exit with the final values in the same registers, using stack // for temporary storage. // round column values // on entry: r0,r1,r4,r5 // on exit: r2,r1,r4,r5 #define fwd_rnd1(arg, table) \ save (0,r1); \ save (1,r5); \ \ /* compute new column values */ \ do_fcol(table, r2,r5,r4,r1, r0,r3, arg); /* idx=r0 */ \ do_col (table, r4,r1,r2,r5, r0,r3); /* idx=r4 */ \ restore(r0,0); \ do_col (table, r1,r2,r5,r4, r0,r3); /* idx=r1 */ \ restore(r0,1); \ do_col (table, r5,r4,r1,r2, r0,r3); /* idx=r5 */ // round column values // on entry: r2,r1,r4,r5 // on exit: r0,r1,r4,r5 #define fwd_rnd2(arg, table) \ save (0,r1); \ save (1,r5); \ \ /* compute new column values */ \ do_fcol(table, r0,r5,r4,r1, r2,r3, arg); /* idx=r2 */ \ do_col (table, r4,r1,r0,r5, r2,r3); /* idx=r4 */ \ restore(r2,0); \ do_col (table, r1,r0,r5,r4, r2,r3); /* idx=r1 */ \ restore(r2,1); \ do_col (table, r5,r4,r1,r0, r2,r3); /* idx=r5 */ // These macros performs an inverse encryption cycle. They are entered with // the first previous round column values in r0,r1,r4,r5 and // exit with the final values in the same registers, using stack // for temporary storage // round column values // on entry: r0,r1,r4,r5 // on exit: r2,r1,r4,r5 #define inv_rnd1(arg, table) \ save (0,r1); \ save (1,r5); \ \ /* compute new column values */ \ do_icol(table, r2,r1,r4,r5, r0,r3, arg); /* idx=r0 */ \ do_col (table, r4,r5,r2,r1, r0,r3); /* idx=r4 */ \ restore(r0,0); \ do_col (table, r1,r4,r5,r2, r0,r3); /* idx=r1 */ \ restore(r0,1); \ do_col (table, r5,r2,r1,r4, r0,r3); /* idx=r5 */ // round column values // on entry: r2,r1,r4,r5 // on exit: r0,r1,r4,r5 #define inv_rnd2(arg, table) \ save (0,r1); \ save (1,r5); \ \ /* compute new column values */ \ do_icol(table, r0,r1,r4,r5, r2,r3, arg); /* idx=r2 */ \ do_col (table, r4,r5,r0,r1, r2,r3); /* idx=r4 */ \ restore(r2,0); \ do_col (table, r1,r4,r5,r0, r2,r3); /* idx=r1 */ \ restore(r2,1); \ do_col (table, r5,r0,r1,r4, r2,r3); /* idx=r5 */ // AES (Rijndael) Encryption Subroutine .global aes_enc_blk .extern ft_tab .extern fl_tab .align 4 aes_enc_blk: push %ebp mov ctx(%esp),%ebp // pointer to context // CAUTION: the order and the values used in these assigns // rely on the register mappings 1: push %ebx mov in_blk+4(%esp),%r2 push %esi mov nrnd(%ebp),%r3 // number of rounds push %edi #if ekey != 0 lea ekey(%ebp),%ebp // key pointer #endif // input four columns and xor in first round key mov (%r2),%r0 mov 4(%r2),%r1 mov 8(%r2),%r4 mov 12(%r2),%r5 xor (%ebp),%r0 xor 4(%ebp),%r1 xor 8(%ebp),%r4 xor 12(%ebp),%r5 sub $8,%esp // space for register saves on stack add $16,%ebp // increment to next round key sub $10,%r3 je 4f // 10 rounds for 128-bit key add $32,%ebp sub $2,%r3 je 3f // 12 rounds for 128-bit key add $32,%ebp 2: fwd_rnd1( -64(%ebp) ,ft_tab) // 14 rounds for 128-bit key fwd_rnd2( -48(%ebp) ,ft_tab) 3: fwd_rnd1( -32(%ebp) ,ft_tab) // 12 rounds for 128-bit key fwd_rnd2( -16(%ebp) ,ft_tab) 4: fwd_rnd1( (%ebp) ,ft_tab) // 10 rounds for 128-bit key fwd_rnd2( +16(%ebp) ,ft_tab) fwd_rnd1( +32(%ebp) ,ft_tab) fwd_rnd2( +48(%ebp) ,ft_tab) fwd_rnd1( +64(%ebp) ,ft_tab) fwd_rnd2( +80(%ebp) ,ft_tab) fwd_rnd1( +96(%ebp) ,ft_tab) fwd_rnd2(+112(%ebp) ,ft_tab) fwd_rnd1(+128(%ebp) ,ft_tab) fwd_rnd2(+144(%ebp) ,fl_tab) // last round uses a different table // move final values to the output array. CAUTION: the // order of these assigns rely on the register mappings add $8,%esp mov out_blk+12(%esp),%ebp mov %r5,12(%ebp) pop %edi mov %r4,8(%ebp) pop %esi mov %r1,4(%ebp) pop %ebx mov %r0,(%ebp) pop %ebp mov $1,%eax ret // AES (Rijndael) Decryption Subroutine .global aes_dec_blk .extern it_tab .extern il_tab .align 4 aes_dec_blk: push %ebp mov ctx(%esp),%ebp // pointer to context // CAUTION: the order and the values used in these assigns // rely on the register mappings 1: push %ebx mov in_blk+4(%esp),%r2 push %esi mov nrnd(%ebp),%r3 // number of rounds push %edi #if dkey != 0 lea dkey(%ebp),%ebp // key pointer #endif mov %r3,%r0 shl $4,%r0 add %r0,%ebp // input four columns and xor in first round key mov (%r2),%r0 mov 4(%r2),%r1 mov 8(%r2),%r4 mov 12(%r2),%r5 xor (%ebp),%r0 xor 4(%ebp),%r1 xor 8(%ebp),%r4 xor 12(%ebp),%r5 sub $8,%esp // space for register saves on stack sub $16,%ebp // increment to next round key sub $10,%r3 je 4f // 10 rounds for 128-bit key sub $32,%ebp sub $2,%r3 je 3f // 12 rounds for 128-bit key sub $32,%ebp 2: inv_rnd1( +64(%ebp), it_tab) // 14 rounds for 128-bit key inv_rnd2( +48(%ebp), it_tab) 3: inv_rnd1( +32(%ebp), it_tab) // 12 rounds for 128-bit key inv_rnd2( +16(%ebp), it_tab) 4: inv_rnd1( (%ebp), it_tab) // 10 rounds for 128-bit key inv_rnd2( -16(%ebp), it_tab) inv_rnd1( -32(%ebp), it_tab) inv_rnd2( -48(%ebp), it_tab) inv_rnd1( -64(%ebp), it_tab) inv_rnd2( -80(%ebp), it_tab) inv_rnd1( -96(%ebp), it_tab) inv_rnd2(-112(%ebp), it_tab) inv_rnd1(-128(%ebp), it_tab) inv_rnd2(-144(%ebp), il_tab) // last round uses a different table // move final values to the output array. CAUTION: the // order of these assigns rely on the register mappings add $8,%esp mov out_blk+12(%esp),%ebp mov %r5,12(%ebp) pop %edi mov %r4,8(%ebp) pop %esi mov %r1,4(%ebp) pop %ebx mov %r0,(%ebp) pop %ebp mov $1,%eax ret