Initial commit.

1 files changed, 39 insertions, 0 deletions

diff --git a/README.md b/README.md
new file mode 100644
index 0000000..c055476
--- /dev/null
+++ b/README.md
@@ -0,0 +1,39 @@
+# Hypodermic
+
+The ability to inject a shared library into a program is generally very
+desirable, allowing a researcher to execute code from the address space of
+another process. The preferred method of performing this on Linux, specifying
+environment variables such as `LD_PRELOAD`, requires that the dynamic linker is
+present and supports it. In a majority of cases, this will work perfectly
+fine. In fact, this method is extremely powerful and any calls a binary makes to
+a library will be directed to the injected shared object. However, there are
+cases in which one would want to merely inject code to be run from a debugger,
+not caring about whether or not library calls made by the binary are
+redirected. There have been a few attempts at this in the past, such as
+[linux-inject][1], which makes use of the `__libc_dlopen_mode` routine in glibc.
+This is oftentimes unsuccessful, being very dependent upon how glibc was
+compiled.
+
+The goal of Hypodermic is to find a means of injecting a dynamic library into
+any Linux executable, even ones that are statically-linked, and tranferring this
+method over to [PINCE][2] when it is stable enough.
+
+Hypodermic is free software, licensed under the [GNU General Public License.][3]
+
+
+## Current Attempts
+
+The initial, honestly quite naïve, attempt at implementing this was to inject
+code that would map the entire shared object into the address space of the
+inferior process, and only parsing the ELF data to get the offsets of library
+routines. This did not work, as the process of loading an ELF library into
+memory is far more complicated than calling mmap(2) on the file.
+
+The second iteration also involves injecting code into the inferior process, but
+instead maps the Linux runtime linker into memory to make use of its existing
+GOT/PLT setup functionality.
+
+
+[1]: https://github.com/gaffe23/linux-inject
+[2]: https://github.com/korcankaraokcu/PINCE
+[3]: https://www.gnu.org/licenses/gpl.html