/* ARM assembly Raspberry PI  */
/*  program sha1-1.s   */
/* use with library openssl */
/* link with gcc option  -lcrypto -lssl  */

/* REMARK 1 : this program use routines in a include file
   see task Include a file language arm assembly
   for the routine affichageMess conversion10
   see at end of this program the instruction include */

/* for constantes see task include a file in arm assembly */
/************************************/
/* Constantes                       */
/************************************/
.include "../constantes.inc"

.equ SHA_DIGEST_LENGTH, 20

/*******************************************/
/* Fichier des macros                       */
/********************************************/
.include "../../ficmacros.s"

/*********************************/
/* Initialized data              */
/*********************************/
.data
szMessRosetta:        .asciz "Rosetta Code"
                      .equ LGMESSROSETTA, . - szMessRosetta - 1
szCarriageReturn:     .asciz "\n"
szMessSup64:          .ascii "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
                      .ascii "abcdefghijklmnopqrstuvwxyz"
                      .asciz "1234567890AZERTYUIOP"
                      .equ LGMESSSUP64, . - szMessSup64 - 1
szMessTest2:          .asciz "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"
                      .equ LGMESSTEST2,  . - szMessTest2 - 1

/*********************************/
/* UnInitialized data            */
/*********************************/
.bss
.align 4
szMessResult:              .skip 24
sZoneConv:                 .skip 24
/*********************************/
/*  code section                 */
/*********************************/
.text
.global main
main:                                      @ entry of program

    ldr r0,iAdrszMessRosetta
    mov r1,#LGMESSROSETTA
    ldr r2,iAdrszMessResult
    bl SHA1                                @ appel fonction openssl
    ldr r0,iAdrszMessResult
    bl displaySHA1

100:                                       @ standard end of the program
    mov r0, #0                             @ return code
    mov r7, #EXIT                          @ request to exit program
    svc #0                                 @ perform the system call

iAdrszMessRosetta:        .int szMessRosetta
iAdrszCarriageReturn:     .int szCarriageReturn
iAdrszMessResult:         .int szMessResult
iAdrsZoneConv:            .int sZoneConv
iAdrszMessSup64:          .int szMessSup64
iAdrszMessTest2:          .int szMessTest2
/******************************************************************/
/*     display hash  SHA1                         */
/******************************************************************/
/* r0 contains the address of hash  */
displaySHA1:
    push {r1-r3,lr}                  @ save  registres
    mov r3,r0
    mov r2,#0
1:
    ldr r0,[r3,r2,lsl #2]            @ load 4 bytes
    rev r0,r0                        @ reverse bytes
    ldr r1,iAdrsZoneConv
    bl conversion16                  @ conversion hexa
    ldr r0,iAdrsZoneConv
    bl affichageMess
    add r2,r2,#1
    cmp r2,#SHA_DIGEST_LENGTH / 4
    blt 1b                           @ and loop
    ldr r0,iAdrszCarriageReturn
    bl affichageMess                 @ display message
100:
    pop {r1-r3,lr}                   @ restaur registers
    bx lr                            @ return
/***************************************************/
/*      ROUTINES INCLUDE                 */
/***************************************************/
.include "../affichage.inc"