Hola compañeros. Hace unos días me encontré con un gran problema cuando quise "meterle mano" a una laptop DELL Latitude D620, la BIOS estaba bloqueada y fue un gran problema encontrar la solución. Por suerte, existe el código para ingresarlo en consola en linux y poder descifrar la contraseña.
El código se ingresa en una hoja de texto y guardarlo como dell.c El código es el siguiente:
#include <stdio.h>
#include <string.h>
#include <time.h>
#define mystr "My own utility. Copyright (C) 2007-2010 hpgl, Russia"
#define allow595B
#define allowA95B
#define allow2A7B
#define fSVCTAG 0
#define fHDDSN 1
#define fHDDold 2
#define t595B 0
#define tD35B 1
#define tA95B 2
#define t2A7B 3
#ifdef allow595B
#define f595B
#endif
#ifdef allowA95B
#define f595B
#endif
#ifdef allow2A7B
#define f595B
#endif
char bSuffix[]="595BD35BA95B2A7B";
char scancods[]="\00\0331234567890-=\010\011qwertyuiop[]\015\377asdfghjkl;'`\377\\zxcvbnm,./";
char encscans[]={0x05,0x10,0x13,0x09,0x32,0x03,0x25,0x11,0x1F,0x17,0x06,0x15, \
0x30,0x19,0x26,0x22,0x0A,0x02,0x2C,0x2F,0x16,0x14,0x07,0x18, \
0x24,0x23,0x31,0x20,0x1E,0x08,0x2D,0x21,0x04,0x0B,0x12,0x2E};
#ifdef allow2A7B
char chartabl2A7B[72]="012345679abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ0";
#endif
unsigned int MD5magic[64]={
0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee,
0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be,
0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,
0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa,
0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8,
0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed,
0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,
0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c,
0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x4881d05,
0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,
0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039,
0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1,
0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391};
unsigned char inData[23],outData[16];
char buf1output[32], buf1input[20];
char bug4;
void calcsuffix(char bfunc, char btype, char *outbuf);
void initData(void) {
*(int *)(&outData[0]) =0x67452301;
*(int *)(&outData[4]) =0xEFCDAB89;
*(int *)(&outData[8]) =0x98BADCFE;
*(int *)(&outData[12])=0x10325476;
}
typedef int (encfuncT1) (int num1, int num2, int num3);
#ifdef f595B
int enc0F2(int num1, int num2, int num3) {return (((~num3 ^ num2) & num1) ^ ~num3);}
int enc0F4(int num1, int num2, int num3) {return (( ~num2 ^ num1) ^ num3); }
int enc0F5(int num1, int num2, int num3) {return (( ~num1 | ~num3) ^ num2); }
#endif
int enc1F2(int num1, int num2, int num3) {return ((( num3 ^ num2) & num1) ^ num3);}
int enc1F4(int num1, int num2, int num3) {return (( num2 ^ num1) ^ num3); }
int enc1F5(int num1, int num2, int num3) {return (( num1 | ~num3) ^ num2); }
int encF3 (int num1, int num2, int num3) {return ((( num1 ^ num2) & num3) ^ num2);}
typedef int (encfuncT2)(encfuncT1 func, int num1, int num2, int num3, int key);
int enc1F1 (encfuncT1 func, int num1, int num2, int num3, int key)
{
return func(num1,num2,num3)+key;
}
#ifdef f595B
int enc0F1 (encfuncT1 func, int num1, int num2, int num3, int key)
{
return func(num1,num2,num3)-key;
}
#endif
unsigned int rol(unsigned int t, int bitsrot)
{
return (t >> (32-bitsrot)) | (t << bitsrot);
}
void blockEncodeF(int *outdata, int *encblock, encfuncT2 func1,
encfuncT1 func2, encfuncT1 func3, encfuncT1 func4, encfuncT1 func5 )
{
char S[4][4] = {{ 7, 12, 17, 22 },{ 5, 9, 14, 20 },{ 4, 11, 16, 23 },{ 6, 10, 15, 21 }};
int A,B,C,D,t,i;
A=outdata[0];
B=outdata[1];
C=outdata[2];
D=outdata[3];
for (i=0;i<64;i++) { t=MD5magic[i]; switch (i>>4) {
case 0: t=A+func1(func2,B,C,D, t+encblock[(i) & 15]); break;
case 1: t=A+func1(func3,B,C,D, t+encblock[(i*5+1) & 15]); break;
case 2: t=A+func1(func4,B,C,D, t+encblock[(i*3+5) & 15]); break;
case 3: t=A+func1(func5,B,C,D, t+encblock[(i*7) & 15]); break;
}
A=D; D=C; C=B; B+=rol(t,S[i>>4][i&3]);
};
outdata[0]+=A;
outdata[1]+=B;
outdata[2]+=C;
outdata[3]+=D;
}
void blockEncode(char *outdata, int *encblock, char btype) {
if (btype==tD35B)
blockEncodeF((int *)outdata,encblock,enc1F1,enc1F2,encF3,enc1F4,enc1F5);
#ifdef f595B
else
blockEncodeF((int *)outdata,encblock,enc0F1,enc0F2,encF3,enc0F4,enc0F5);
#endif
}
void encode(char *inbuf,int cnt,char btype) {
int encBlock[16];
char *ptr;
initData();
memcpy(encBlock,inbuf,cnt);
ptr=&((char *)encBlock)[cnt];
*ptr++=0x80;
memset(ptr,0,64-1-cnt);
encBlock[16-2]=((unsigned int)cnt << 3);
blockEncode(outData,encBlock,btype);
}
void psw(char bfunc, char btype, char *outbuf) {
int cnt,i,lenpsw,r;
if (bfunc==fHDDold) {
memcpy(inData,buf1input,11);
// calcsuffix(bfunc,btype,outbuf);
for (cnt=0;cnt<8;cnt++) outbuf[cnt]= scancods[ outbuf[cnt] ]; } else { memset(inData,0,sizeof(inData)); if (bfunc==fSVCTAG) cnt=7; else cnt=11; if ((bfunc==fHDDSN) && (btype==tA95B)) memcpy(inData,&buf1input[3],cnt-3); else memcpy(inData,buf1input,cnt); if (btype==t595B) memcpy(&inData[cnt],&bSuffix[0],4); else if (btype==tD35B) memcpy(&inData[cnt],&bSuffix[4],4); else if (btype==tA95B) memcpy(&inData[cnt],&bSuffix[0],4); else if (btype==t2A7B) memcpy(&inData[cnt],&bSuffix[12],4); cnt += 4; inData[cnt] = inData[4] & 0x1F; inData[cnt+1] = ((inData[4] >> 5) | (((inData[3] >> 5) | (inData[3] << 3)) & 0xF1) & 0x1F); inData[cnt+2] = ((inData[3] >> 2) & 0x1F);
inData[cnt+3] = (inData[3] >> 7) | ((inData[2] << 1) & 0x1F); inData[cnt+4] = (inData[2] >> 4) | ((inData[1] << 4) & 0x1F); inData[cnt+5] = (inData[1] >> 1) & 0x1F;
inData[cnt+6] = (inData[1] >> 6) | ((inData[0] << 2) & 0x1F); inData[cnt+7] = (inData[0] >> 3) & 0x1F;
for (i=cnt;i<8+cnt;i++) {
r = 0xAA;
if (inData[i] & 1)
r ^= inData[4];
if (inData[i] & 2)
r ^= inData[3];
if (inData[i] & 4)
r ^= inData[2];
if (inData[i] & 8)
r ^= inData[1];
if (inData[i] & 16)
r ^= inData[0];
inData[i] = encscans[r % sizeof(encscans)];
}
cnt = 23;
encode(inData,cnt,btype);
r = outData[0] % 9;
lenpsw = 0;
for (cnt=0;cnt<16;cnt++) {
if ((r <= cnt) && (lenpsw<8)) { buf1output[lenpsw++] = scancods[encscans[outData[cnt] % sizeof(encscans)]]; } } } } int main(int argc, char *argv[]) { unsigned char len,len1,bfunc,eol=1,echo=0, *minus,s2[20]; signed char btype; int argn=0; if (argc>1)
echo=1;
if (!echo)
fputs("" mystr "\n" \
"Short service tag should be right padded with '*' up to length 7 chars\n" \
"HDD serial number is right 11 chars from real HDDSerNum left padded with '*'\n" \
"Some BIOSes has left pad HDD serial number with spaces instead '*'\n",stdout);
while (!feof(stdin)) {
if ((argc<=1) && argn) break; fputs("Input: #",stdout); if (argc>1) {
strncpy(buf1input,argv[++argn],sizeof(buf1input));argc--;
}
else {
if (!eol) while (!feof(stdin) && (fgetc(stdin)!='\n')); eol=0;
if (fgets(buf1input,16+1+1,stdin)==NULL) {
if (echo) fputs("\n",stdout);
break;
}
}
len=strlen(buf1input);
if (len && (buf1input[len-1]=='\n')) {len--;eol=1;buf1input[len]=0;}
if (echo) {fputs(buf1input,stdout);fputs("\n",stdout);}
minus=strchr(buf1input,'-');
if (len==11) {
if (minus!=NULL) {
fputs("- Incorrect input\n",stdout);
continue;
}
bfunc=fHDDold;
fputs("By HDD serial number for older BIOS: ",stdout);
} else {
if (len==0) break;
if (minus==NULL) {
fputs("- No BIOS type found in input string, must be followed by -595B and other registered\n",stdout);
continue;
}
len1=minus-(unsigned char*)buf1input;
btype=-1;
#ifdef allow595B
if (strncmp(&buf1input[len1+1],&bSuffix[0],4)==0) btype=t595B;
else
#endif
if (strncmp(&buf1input[len1+1],&bSuffix[4],4)==0) btype=tD35B;
else
#ifdef allowA95B
if (strncmp(&buf1input[len1+1],&bSuffix[8],4)==0) btype=tA95B;
else
#endif
#ifdef allow2A7B
if (strncmp(&buf1input[len1+1],&bSuffix[12],4)==0) btype=t2A7B;
#endif
if (btype<0) {
fputs("- Invalid service tag in input string, allowed only -D35B and other registered\n",stdout);
continue;
}
struct tm *time1; time_t timer1=time(NULL);
time1=gmtime(&timer1);
strftime(s2,sizeof(s2),"%d.%m.%Y %H:%M",time1);
fputs(s2,stdout);
fputs(" DELL ",stdout);
if (len1==7) {
bfunc=fSVCTAG;
fputs("service tag: ",stdout);
fputs(buf1input,stdout);
} else
if (len1==11) {
bfunc=fHDDSN;
fputs("HDD serial number: ",stdout);
fputs(buf1input,stdout);
}
else {
fputs("- Incorrect input, must be 7 chars service tag or 11 chars HDD serial number\n",stdout);
continue;
}
}
psw(bfunc,btype,buf1output);
fputs(" password: ",stdout);
fputs(buf1output,stdout);
if (bug4) fputs(" !bug4 warning - password may not work!",stdout);
if (btype==t595B) if (bfunc==fSVCTAG) { //to check if A95B bug
char mpw1[20];
strcpy(mpw1,buf1output);
psw(bfunc,tA95B,buf1output);
if (strcmp(mpw1,buf1output)!=0) {
fputs(" passwordA95B: ",stdout);
fputs(buf1output,stdout);
}
}
fputs("\n",stdout);
}
return 0;
}
Lo siguiente que debemos hacer es teclear lo siguiente en consola:
sudo nano dell.c
Después debemos compilar el archivo:
sudo gcc -dell dell.cAhora, simplemente corremos el programa
./dell.cUna vez ejecutado el programa, nos pedirá el código que nos muestra la pantalla del bloqueo de nuestra laptop DELL.
