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author | 2011-10-06 00:07:33 -0400 | |
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committer | 2011-10-08 14:53:27 -0400 | |
commit | caa17d7d9e10e0ef49b3df0d0bf1ceb007dd64d5 (patch) | |
tree | 4ae6c1a00ca72652ed68a1334bd038f854820c7d | |
parent | scripts/revdep-paxmark: deprecated (diff) | |
download | elfix-caa17d7d9e10e0ef49b3df0d0bf1ceb007dd64d5.tar.gz elfix-caa17d7d9e10e0ef49b3df0d0bf1ceb007dd64d5.tar.bz2 elfix-caa17d7d9e10e0ef49b3df0d0bf1ceb007dd64d5.zip |
scripts/paxmodule.c: add code to read pax flags
-rw-r--r-- | scripts/paxmodule.c | 127 | ||||
-rwxr-xr-x | scripts/setup.py | 3 |
2 files changed, 122 insertions, 8 deletions
diff --git a/scripts/paxmodule.c b/scripts/paxmodule.c index 03ba794..1b3e1eb 100644 --- a/scripts/paxmodule.c +++ b/scripts/paxmodule.c @@ -1,5 +1,28 @@ #include <Python.h> +#include <stdio.h> //remove when you remove printf +#include <string.h> + +#include <gelf.h> + +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <unistd.h> + + +#define HF_PAX_PAGEEXEC 1 +#define HF_PAX_EMUTRAMP 2 +#define HF_PAX_MPROTECT 4 +#define HF_PAX_RANDMMAP 8 +#define HF_PAX_RANDEXEC 16 +#define HF_PAX_SEGMEXEC 32 + +#define EI_PAX 14 // Index to read the PaX flags into ELF header e_ident[] array + +#define BUF_SIZE 7 //Buffer for holding human readable flags + + static PyObject * pax_getflags(PyObject *, PyObject *); static PyMethodDef PaxMethods[] = { @@ -27,21 +50,111 @@ initpax(void) static PyObject * pax_getflags(PyObject *self, PyObject *args) { - const char *value; - int sts; + const char *f_name; + int fd, sts; + Elf *elf; + + GElf_Ehdr ehdr; + char ei_buf[BUF_SIZE]; + uint16_t ei_flags; + + GElf_Phdr phdr; + char pt_buf[BUF_SIZE]; + char found_pt_pax; + size_t i, phnum; + + memset(ei_buf, 0, BUF_SIZE); + memset(pt_buf, 0, BUF_SIZE); - if (!PyArg_ParseTuple(args, "s", &value)) + if (!PyArg_ParseTuple(args, "s", &f_name)) + { + PyErr_SetString(PaxError, "pax_getflags: PyArg_ParseTuple failed"); return NULL; + } - printf("%s\n", value); + if(elf_version(EV_CURRENT) == EV_NONE) + { + PyErr_SetString(PaxError, "pax_getflags: library out of date"); + return NULL; + } - sts = 1; + if((fd = open(f_name, O_RDONLY)) < 0) + { + PyErr_SetString(PaxError, "pax_getflags: open() failed"); + return NULL; + } - if (sts < 0) + if((elf = elf_begin(fd, ELF_C_READ_MMAP, NULL)) == NULL) { - PyErr_SetString(PaxError, "pax_getflags failed"); + PyErr_SetString(PaxError, "pax_getflags: elf_begin() failed"); return NULL; } + if(elf_kind(elf) != ELF_K_ELF) + { + PyErr_SetString(PaxError, "pax_getflags: elf_kind() failed: this is not an elf file."); + return NULL; + } + + + found_pt_pax = 0; + elf_getphdrnum(elf, &phnum); + for(i=0; i<phnum; ++i) + { + if(gelf_getphdr(elf, i, &phdr) != &phdr) + { + PyErr_SetString(PaxError, "pax_getflags: gelf_getphdr() failed"); + return NULL; + } + + if(phdr.p_type == PT_PAX_FLAGS) + { + found_pt_pax = 1; + + pt_buf[0] = phdr.p_flags & PF_PAGEEXEC ? 'P' : + phdr.p_flags & PF_NOPAGEEXEC ? 'p' : '-' ; + + pt_buf[1] = phdr.p_flags & PF_SEGMEXEC ? 'S' : + phdr.p_flags & PF_NOSEGMEXEC ? 's' : '-'; + + pt_buf[2] = phdr.p_flags & PF_MPROTECT ? 'M' : + phdr.p_flags & PF_NOMPROTECT ? 'm' : '-'; + + pt_buf[3] = phdr.p_flags & PF_EMUTRAMP ? 'E' : + phdr.p_flags & PF_NOEMUTRAMP ? 'e' : '-'; + + pt_buf[4] = phdr.p_flags & PF_RANDMMAP ? 'R' : + phdr.p_flags & PF_NORANDMMAP ? 'r' : '-'; + + pt_buf[5] = phdr.p_flags & PF_RANDEXEC ? 'X' : + phdr.p_flags & PF_NORANDEXEC ? 'x' : '-'; + } + } + + if(found_pt_pax) + printf("PT_PAX: %s\n", pt_buf); + else + { + if(gelf_getehdr(elf, &ehdr) != &ehdr) + { + PyErr_SetString(PaxError, "pax_getflags: gelf_getehdr() failed"); + return NULL; + } + + ei_flags = ehdr.e_ident[EI_PAX] + (ehdr.e_ident[EI_PAX + 1] << 8); + + ei_buf[0] = ei_flags & HF_PAX_PAGEEXEC ? 'p' : 'P'; + ei_buf[1] = ei_flags & HF_PAX_SEGMEXEC ? 's' : 'S'; + ei_buf[2] = ei_flags & HF_PAX_MPROTECT ? 'm' : 'M'; + ei_buf[3] = ei_flags & HF_PAX_EMUTRAMP ? 'E' : 'e'; + ei_buf[4] = ei_flags & HF_PAX_RANDMMAP ? 'r' : 'R'; + ei_buf[5] = ei_flags & HF_PAX_RANDEXEC ? 'X' : 'x'; + + printf("EI_PAX: %s\n", ei_buf); + } + + elf_end(elf); + close(fd); + return Py_BuildValue("i", sts); } diff --git a/scripts/setup.py b/scripts/setup.py index 317efbd..77854f1 100755 --- a/scripts/setup.py +++ b/scripts/setup.py @@ -4,7 +4,8 @@ from distutils.core import setup, Extension module1 = Extension( name='pax', - sources = ['paxmodule.c'] + sources = ['paxmodule.c'], + libraries = ['elf'], ) setup( |