This simplifies the interface that proxies export to the library but also relies
upon the assumption that a proxy chain starts with a TCP connection from the
scanner to the next hop proxy. That will be enough ATM.
When establishing the tunnel through proxy chain, we need to track status of
each proxy (storing R/W buffers, stats, retries...).
This patch lets proxies store and manage whatever structure they want to have
for this in a Nsock IOD. Since types can differ between proxy types, the
proxy_info are stored as a list of void *, ordered like the proxy nodes.
Proxy backends are selected at runtime. Each proxy exports a list of operations
to the rest of the library. This is similar to the way IO engines are
implemented within nsock.
Externally:
The calling application can build a proxychain object and assign it to one (or
more) NSP. Once a NSP get assigned a proxychain it's not possible to remove
it so that consistency is (should be...) ensured.
Internally:
An IOD comes with a proxychain context structure storing the whole tunnel
state. Also each proxy type now has a table of associated functions to use
as hooks for TCP connects(), read() and write() requests. As a result, adding
support of new proxy type should be easier. Code also gains readability in
comparison to large switch/cases that redirect the execution flow according to
the given proxy type.
- Removed dead code.
- Fixed style, improved consistency.
- Replaced FILESPACE_LENGTH and FILESPACE_STR macros by identical
static inline functions.
- Made fs_cat() a regular function. There's no actual benefit of
having it inlined.
Reworked the logging infrastructure to make it more flexible
and consistent.
Updated nmap, nping and ncat accordingly. Nsock log level can
now be adjusted at runtime by pressing d/D in nmap.
There was a bug here where AF_INET6 was used instead of AF_UNIX in the
HAVE_SYS_UN_H section. This masked another bug, which was that the
HAVE_SYS_UN_H section inadvertently extended into what was supposed to
be the HAVE_IPV6 section.
I'm not sure why I wasn't seeing this error before:
engine_poll.c: In function ‘poll_loop’:
engine_poll.c:352:46: error: ‘EINTR’ undeclared (first use in this function)
engine_poll.c:352:46: note: each undeclared identifier is reported only once for each function it appears in
All the information passed as arguments is present in an iod, and we
only call this with members of one iod. Change it to accept just an iod
as an argument.
Implementation of UNIX-domain sockets functionality
for Nsock. Also some minor necessary changes to
existing Nsock functions, to work properly with
UNIX-domain sockets.
