debugging suite

A set of tools for static and dynamic analysis of ELF binaries.
Implements behavior similar to nm, strace, and gdb.

my_nm displays the symbol table of an ELF binary, my_strace traces
system calls made by a program, and my_db lets you debug a binary
interactively.

Usage:
$ ./my_nm /path/to/binary
    0000000000000000	0	STT_NOTYPE	STB_LOCAL	STV_DEFAULT	UND
    0000000000000000	0	STT_SECTION	STB_LOCAL	STV_DEFAULT	.text
    0000000000000000	0	STT_SECTION	STB_LOCAL	STV_DEFAULT	.rodata
    0000000000000000	24	STT_FUNC	STB_GLOBAL	STV_DEFAULT	.text	do_calc
    0000000000000018	98	STT_FUNC	STB_GLOBAL	STV_DEFAULT	.text	main
    0000000000000000	0	STT_NOTYPE	STB_GLOBAL	STV_DEFAULT	UND	printf

$ ./my_strace /path/to/binary [forbidden_syscalls]
    brk(addr = 0x0) = 93824992378880
    arch_prctl() = -22
    mmap(addr = 0x0, length = 8192, prot = 3, flags = -134308681, fd = -1, offset = 0) = 140737353854976
    access(pathname = "/etc/ld.so.preload", mode = 4) = -2
    ...
    forbidden syscall blocked: read
    close(fd = 3) = 0
    /bin/ls: error while loading shared libraries: /lib/x86_64-linux-gnu/libselinux.so.1: cannot read file data: Operation not permitted
    writev(fd = 2, iov = 0x7fffffffd040, iovcnt = 10) = 133
    program exited with code 127

$ ./my_db /path/to/binary
    > continue
    before breakpoint
    > registers
    rax: 0x14 rbx: 0x7fffffffde08
    ...
    > quit

my_db provides the following commands to control a running program:
    *	help                 display available commands
    *	quit                 exit the debugger
    *	kill                 kill the debugged process
    *	continue             resume execution
    *	registers            display process registers
    *	x/d/u count addr     dump memory in hex, signed or unsigned decimal
    *	break addr|symbol    set a breakpoint
    *	blist                list active breakpoints
    *	bdel N               delete breakpoint N
    *	bt                   display the callstack