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scrapbird/r21337patch.py

Created November 7, 2017 04:05
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  1. scrapbird created this gist Nov 7, 2017.
    37 changes: 37 additions & 0 deletions r21337patch.py
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,37 @@
    #!/usr/bin/env python

    import r2pipe
    import sys

    r2 = r2pipe.open()

    # r2 base address
    delta = 0x400000


    def patchByte(addr, oldbyte, newbyte):
    print "[-] Patching byte at addr: {} {}->{}".format(hex(addr), oldbyte, newbyte)
    r2.cmd("wx {} @ {}".format(newbyte, hex(addr)))
    res = r2.cmd("p8 1 @ {}".format(hex(addr)))
    if res != newbyte:
    print "[!] Error writing byte at {}".format(hex(addr))


    # Check file permissions
    if r2.cmd("i~mode[1]").find("w") < 0:
    print "Please open file in write mode (oo+)"
    quit()

    # Check args
    if len(sys.argv) != 2:
    print "Please run script with path to patch file"
    quit()

    with open(sys.argv[1], 'r') as f:
    for line in f:
    if not line.startswith(">"):
    line = line.rstrip("\n")
    split = line.split(":")
    addr = int(split[0], 16) + delta
    bytesplit = split[1].split("->")
    patchByte(addr, bytesplit[0], bytesplit[1])