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Enhancement in documentation

Yann Weber 1 year ago
parent
commit
32a40e8143
3 changed files with 97 additions and 3 deletions
  1. 2
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      Makefile.am
  2. 4
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      asm_env.h
  3. 91
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      asmsh.h

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Makefile.am View File

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 lint: $(LINT)
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 lint: $(LINT)
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+doxygen:
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+	$(MAKE) -C docs

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asm_env.h View File

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 /** Run the next instruction
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 /** Run the next instruction
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  * @param asmsh_env_t* The run environment
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  * @param asmsh_env_t* The run environment
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- * @param int* If not null will be set to the status of the child PID (error cases)
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- * @return 0 if no error from the child pid else -1 and wstatus is set to the child status
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+ * @param int* If not null will be set to the status of the child PID (error
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+ * cases)
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+ * @return 0 if no error else -1, if the child is not trapped as expected, 1 is
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+ * returned and wstatus is set to the child status (see man 2 waitpid)
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  */
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  */
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 int asmsh_env_step(asmsh_env_t *env, int *status);
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 int asmsh_env_step(asmsh_env_t *env, int *status);
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asmsh.h View File

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 @section SYNOPSIS
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 @section SYNOPSIS
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 asmsh [OPTIONS]...
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 asmsh [OPTIONS]...
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 @section DESCRIPTION
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 @section DESCRIPTION
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-A shell designed to run assembly.
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+A shell designed to run assembly (for the moment only x86_64 is supported).
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 A simple programm is spawned by the shell, and each instructions are runned in the
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 A simple programm is spawned by the shell, and each instructions are runned in the
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 subprocess environment.
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 subprocess environment.
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+@section UI
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+
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+For the moment, the UI is implemented using GNU readline with basic support for
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+completion (using tab).
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+
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+The prompt is composed like "asmsh@RIPVAL > " where RIPVAL is the RIP register (
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+Instruction Pointer ) value in hexadecimal.
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+
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+@section INSTRUCTIONS
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+
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+The shell uses the GNU as compiler from binutils, the instructions syntax
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+follows GAS syntax.
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+
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+For the moment GAS can only be used with the AT&T syntax.
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+
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+Details on x86 syntax can be found in GAS documentation at
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+<pre>
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+[https://sourceware.org/binutils/docs-2.40/as.html#i386_002dSyntax]
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+</pre>
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+
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+The list & names of the registers can be found at the same place
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+<pre>
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+[https://sourceware.org/binutils/docs-2.40/as.html#i386_002dRegs]
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+</pre>
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+
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+The list & documentation of the instructions for the x86_64 platform can be
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+found in the 1st volume of "AMD64 Architecture Programmer’s Manual", in section
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+3.3 Instruction summary
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+<pre>
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+[https://www.amd.com/en/support/tech-docs/amd64-architecture-programmers-manual-volumes-1-5]
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+</pre>
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+
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+Or in the Intel's equivalent document, namely the 
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+"Intel® 64 and IA-32 Architectures Software Developer’s Manual"
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+<pre>
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+[https://cdrdv2-public.intel.com/774494/325462-sdm-vol-1-2abcd-3abcd.pdf]
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+</pre>
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+
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+@section shell_cmds COMMANDS
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+
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+@par .bytecode
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+Compile an instruction and display it's bytecode
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+@par .flags
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+Display the CPU flags
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+@par .help [COMMAND]
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+Display the builtin help or the help of the command gioven as argument
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+@par .maps
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+Display process memory maps
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+@par .quit
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+Exit the shell
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+@par .regs
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+Display the CPU registers values
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+@par .syscalls
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+Print syscalls names and numbers
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+@par .reset
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+Reset the shell (spawn a new process)
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+
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+@section EXAMPLES
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+
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+@subsection example_exit Exit with a specific status
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+
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+<pre>
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+asmsh@0x7f55d2433000 > mov $60, \%rax
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+asmsh@0x7f55d2433005 > mov $0x2a, \%rdi
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+asmsh@0x7f55d243300a > syscall
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+Child exited with status 42
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+Exit with status 42
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+</pre>
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+
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+@subsection example_hello Print a message to stdout
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+
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+<pre>
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+asmsh@0x7f6e312e5000 > mov $0x0a6f6c6c, \%rax
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+asmsh@0x7f6e312e5005 > shl $(8*2), \%rax
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+asmsh@0x7f6e312e5009 > or $0x6548, \%rax
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+asmsh@0x7f6e312e500f > push \%rax
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+asmsh@0x7f6e312e5010 > mov $1, \%rax
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+asmsh@0x7f6e312e5015 > mov \%rax, \%rdi
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+asmsh@0x7f6e312e5018 > mov \%rsp, \%rsi
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+asmsh@0x7f6e312e501b > mov $6, \%rdx
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+asmsh@0x7f6e312e5020 > syscall
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+Hello
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+asmsh@0x7f6e312e5022 > 
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+</pre>
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+
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+@section TODO TODOLIST
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+
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+@todo Add switch between intel's & AT&T's syntaxes.
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+@todo Add support for label declarations & references
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+
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 @section AUTHOR
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 @section AUTHOR
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 Written by Yann Weber &lt;yann.weber@members.fsf.org&gt;
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 Written by Yann Weber &lt;yann.weber@members.fsf.org&gt;
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