Koraidon

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# Thank you: https://github.com/Lzhiyong/termux-ndk/blob/master/patches/align_fix.py
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import struct
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import sys
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import os
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if len(sys.argv) < 2:
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    print('Usage: ' + os.path.basename(sys.argv[0]) + ' input_file')
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    exit()
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with open(sys.argv[1], 'r+b') as f:
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    f.seek(0)
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    hdr = f.read(16)
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    if hdr[0] != 0x7f or hdr[1] != ord('E') or hdr[2] != ord('L') or hdr[3] != ord('F'):
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        raise Exception('Not an elf file')
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    if hdr[4] == 1:
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        # 32 bit code
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        f.seek(28)
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        offset = struct.unpack('<I', f.read(4))[0]
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        f.seek(42)
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        phsize = struct.unpack('<H', f.read(2))[0]
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        phnum = struct.unpack('<H', f.read(2))[0]
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        for i in range(0, phnum):
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            f.seek(offset + i * phsize)
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            t = struct.unpack('<I', f.read(4))[0]
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            if t == 7:
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                f.seek(28 - 4, 1)
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                align = struct.unpack('<I', f.read(4))[0]
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                print('Found TLS segment with align = ' + str(align))
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                if align < 32:
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                    print('TLS segment is underaligned, patching')
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                    f.seek(-4, 1)
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                    f.write(struct.pack('<I', 32))
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    elif hdr[4] == 2:
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        # 64 bit code
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        f.seek(32)
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        offset = struct.unpack('<Q', f.read(8))[0]
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        f.seek(54)
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        phsize = struct.unpack('<H', f.read(2))[0]
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        phnum = struct.unpack('<H', f.read(2))[0]
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        for i in range(0, phnum):
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            f.seek(offset + i * phsize)
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            t = struct.unpack('<I', f.read(4))[0]
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            if t == 7:
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                f.seek(48 - 4, 1)
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                align = struct.unpack('<Q', f.read(8))[0]
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                print('Found TLS segment with align = ' + str(align))
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                if align < 64:
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                    print('TLS segment is underaligned, patching')
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                    f.seek(-8, 1)
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                    f.write(struct.pack('<H', 64))
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    else:
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        raise Exception('Unknown file class')
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