Net::SSH2, the Perl wrapping module for libssh2 implements several features*
on top of libssh2 that can fail and so need some mechanism to report the error
condition to the user.
Until now, besides the error state maintained internally by libssh2, another
error state was maintained at the Perl level for every session object and then
additional logic was used to merge both error states. That is a maintenance
nighmare, and actually there is no way to do it correctly and consistently.
In order to allow the high level language to add new features to the library
but still rely in its error reporting features the new function
libssh2_session_set_last_error (that just exposses _libssh2_error_flags) is
introduced.
*) For instance, connecting to a remote SSH service giving the hostname and
port.
Signed-off-by: Salvador Fandino <sfandino@yahoo.com>
Signed-off-by: Salvador Fandiño <sfandino@yahoo.com>
Before this patch "_libssh2_error" required the error message to be a
static string.
This patch adds a new function "_libssh2_error_flags" accepting an
additional "flags" argument and specifically the flag
"LIBSSH2_ERR_FLAG_DUP" indicating that the passed string must be
duplicated into the heap.
Then, the method "_libssh2_error" has been rewritten to use that new
function under the hood.
Signed-off-by: Salvador Fandino <sfandino@yahoo.com>
Signed-off-by: Salvador Fandiño <sfandino@yahoo.com>
If libssh2_session_free is called without the channel being freed
previously by libssh2_channel_free a memory leak could occur.
A mismatch of states variables in session_free() prevent the call to
libssh2_channel_free function. session->state member is used instead of
session->free_state.
It causes a leak of around 600 bytes on every connection on my systems
(Linux, x64 and PPC).
(Debugging done under contract for Accedian Networks)
Fixes#246
INVALID_SOCKET is a special value in Windows representing a
non-valid socket identifier. We were #defining this to -1 on
non-Windows platforms, causing unneccessary namespace pollution.
Let's have our own identifier instead.
Thanks to Matt Lawson for pointing this out.
Fix the bug that libssh2 could not connect if the sftp server
sends data before sending the version string.
http://tools.ietf.org/html/rfc4253#section-4.2
"The server MAY send other lines of data before sending the version
string. Each line SHOULD be terminated by a Carriage Return and Line
Feed. Such lines MUST NOT begin with "SSH-", and SHOULD be encoded
in ISO-10646 UTF-8 [RFC3629] (language is not specified). Clients
MUST be able to process such lines."
Starting now, we unconditionally use the internal replacement functions
for send() and recv() - creatively named _libssh2_recv() and
_libssh2_send().
On errors, these functions return the negative 'errno' value instead of
the traditional -1. This design allows systems that have no "natural"
errno support to not have to invent it. It also means that no code
outside of these two transfer functions should use the errno variable.
When SCP send or recv fails, it gets a special message from the server
with a warning or error message included. We have no current API to
expose that message but the foundation is there. Removed unnecessary use
of session struct fields.
If _libssh2_wait_socket() gets called but there's no direction set to
wait for, this causes a "hang". This code now detects this situation,
set a 1 second timeout instead and outputs a debug output about it.
The new function takes two data areas, combines them and sends them as a
single SSH packet. This allows several functions to allocate and copy
less data.
I also found and fixed a mixed up use of the compression function
arguments that I introduced in my rewrite in a recent commit.
We now allow libssh2_session_flag() to enable compression with a new
flag and I added documentation for the previous LIBSSH2_FLAG_SIGPIPE
flag which I wasn't really aware of!
The function libssh2_session_startup() is now considered deprecated due
to the portability issue with the socket argument.
libssh2_session_handshake() is the name of the replacement.
Replaced -1/SOCKET_NONE errors with appropriate error defines instead.
Made the verbose trace output during banner receiving less annoying for
non-blocking sessions.
Since libssh2 often sets LIBSSH2_ERROR_EAGAIN internally before
_libssh2_wait_socket is called, we can decrease some amount of
confusion in user programs by resetting the error code in this function
to reduce the risk of EAGAIN being stored as error when a blocking
function returns.
As reported on the mailing list, the code path using poll() should
multiple seconds with 1000 to get milliseconds, not divide!
Reported by: Jan Van Boghout
Sending in NULL as the primary pointer is now dealt with by more
public functions. I also narrowed the userauth.c code somewhat to
stay within 80 columns better.
To get the blocking vs non-blocking to work as smooth as possible
and behave better internally, we avoid using the external
interfaces when calling functions internally.
Renamed a few internal functions to use _libssh2 prefix when not
being private within a file, and removed the libssh2_ for one
that was private within the file.
This was triggered by a clang-analyzer complaint that turned out
to be valid, and it made me dig deeper and fix some generic non-
blocking problems I disovered in the code.
While cleaning this up, I moved session-specific stuff over to a
new session.h header from the libssh2_priv.h header.
I'll introduce a new internal function set named
_libssh2_store_u32
_libssh2_store_u64
_libssh2_store_str
That can be used all through the library to build binary outgoing
packets. Using these instead of the current approach removes
hundreds of lines from the library while at the same time greatly
enhances readability. I've not yet fully converted everything to
use these functions.
I've converted LOTS of 'unsigned long' to 'size_t' where
data/string lengths are dealt with internally. This is The Right
Thing and it will help us make the transition to our
size_t-polished API later on as well.
I'm removing the PACKET_* error codes. They were originally
introduced as a set of separate error codes from the transport
layer, but having its own set of errors turned out to be very
awkward and they were then converted into a set of #defines that
simply maps them to the global libssh2 error codes instead. Now,
I'l take the next logical step and simply replace the PACKET_*
defines with the actual LIBSSH2_ERROR_* defines. It will increase
readability and decrease confusion.
I also separated packet stuff into its own packet.h header file.
We reserve ^libssh2_ for public symbols and we use _libssh2 as
prefix for internal ones. I fixed the intendation of all these
edits with emacs afterwards, which then changed it slightly more
than just _libssh2_error() expressions but I didn't see any
obvious problems.
libssh2_error() no longer allocates a string and only accepts a const
error string. I also made a lot of functions use the construct of
return libssh2_error(...) instead of having one call to
libssh2_error() and then a separate return call. In several of those
cases I then also changed the former -1 return code to a more
detailed one - something that I think will not change behaviors
anywhere but it's worth keeping an eye open for any such.
Fix memoary leak: if there was an "output" still allocated when a
session was torn down it needs to be freed in session_free()
Patch by Yoichi Iwaki in bug #2929647