Signed-off-by: dusoleil <howcansocksbereal@gmail.com>

ROP gadgets returned through search from the r2 API will now always
contain a file-relative offset, even if they come from a non-pic binary
using a fixed baddr.

However, gadgets returned through the ELF API will be mapped according
to the ELF's Symtbl.  This ensures the correct offset is returned
following a library leak, and allows the user to always safely insert an
ELF-returned gadget into that ELF's Symtbl without issue.

Signed-off-by: Malfurious <m@lfurio.us>
Signed-off-by: dusoleil <howcansocksbereal@gmail.com>

Signed-off-by: dusoleil <howcansocksbereal@gmail.com>

Signed-off-by: dusoleil <howcansocksbereal@gmail.com>

On ELF construction, call r2.get_bin_info() and keep the results under
the psuedo-namespaces .info and .security.  Also add a pretty-print to
these in a tabulated form.  Also rewrite the ELF pretty-print to just
summarize and not print out the entirety of .sym.  Lastly, fixed a small
bug where ELF could crash on construction if ldd fails (loading a
non-native ELF, for instance).

Signed-off-by: dusoleil <howcansocksbereal@gmail.com>

Code reuse since we were using r2 iI in get_elf_symbols to get the
baddr.  This can cause get_bin_info to be called (and log that it's
being called) multiple times, so I'm also adding the @cache annotation.

Signed-off-by: dusoleil <howcansocksbereal@gmail.com>

Call r2's iI command and return a subset of the fields that we care
about.

Signed-off-by: dusoleil <howcansocksbereal@gmail.com>

Sets the value of rop.len = 10 in r2, to give the search function more
data to sift through.  This is a doubling from the default value (5).

Signed-off-by: Malfurious <m@lfurio.us>
Signed-off-by: dusoleil <howcansocksbereal@gmail.com>

Development on the rop chain builder has produced this upgrade to our
gadget search facility.  The primary advantages in this version are
increased flexibility and runtime performance.

It is now easier to find specific 'stray' instructions (not immediately
followed by a ret) since we search from every position in the data
returned by r2.  If you _do_ want a ret, just specify it in your input
regexes.  For this reason, a dedicated function for locating a simple
'ret' gadget is no longer present - elf.gadget("ret") is the equivalent.

A major change in this version is that we now obtain and operate on r2's
JSON representation of the gadget data.  We now only reach out to r2
once to get all information for a binary (which is cached) and the
actual 'search' is implemented in Python.  This provides a significant
performance speedup in cases where we need many gadgets from one binary,
as r2 doesn't need to inspect the entire file each time.  Additional
caching is done on specific search results, so that 100% redundant
searches are returned immediately.  Access to the raw JSON data is made
available through a new function rop_json(), but is not exposed in the
ELF interface, since it seems like a niche need.

Search results are returned via Gadget objects (or a list thereof),
which contain regular expression Match objects for each assembly
instruction found in the gadget.  This allows the caller to retrieve the
values contained in regular expression capture groups if present.

Also, anecdotally, the search functionality in r2 has seemed to return
false negatives for some queries in the past, whereas I haven't noticed
similar cases with this implementation yet.

Signed-off-by: Malfurious <m@lfurio.us>
Signed-off-by: dusoleil <howcansocksbereal@gmail.com>

This new class is intended to be used to return data from gadget
searches, and is able to be nested within object Symtbls.

Signed-off-by: Malfurious <m@lfurio.us>
Signed-off-by: dusoleil <howcansocksbereal@gmail.com>