Data may remain in zlib internal buffers when inflate() returns Z_OK
and avail_out == 0. In that case, inflate has to be called again.
Also, once all the data has been inflated, it returns Z_BUF_ERROR to
signal that the input buffer has been exhausted.
Until now, the way to detect that a packet payload had been completely
decompressed was to check that no data remained on the input buffer
but that didn't account for the case where data remained on the internal
zlib buffers.
That resulted in packets not being completely decompressed and the
missing data reappearing on the next packet, though the bug was masked
by the buffer allocation algorithm most of the time and only manifested
when transferring highly compressible data.
This patch fixes the zlib usage.
Signed-off-by: Salvador <sfandino@yahoo.com>
After filling the read buffer with data from the read queue, when the
window size was too small, "libssh2_channel_receive_window_adjust" was
called to increase it. In non-blocking mode that function could return
EAGAIN and, in that case, the EAGAIN was propagated upwards and the data
already read on the buffer lost.
The function was also moving between the two read states
"libssh2_NB_state_idle" and "libssh2_NB_state_created" both of which
behave in the same way (excepting a debug statment).
This commit modifies "_libssh2_channel_read" so that the
"libssh2_channel_receive_window_adjust" call is performed first (when
required) and if everything goes well, then it reads the data from the
queued packets into the read buffer.
It also removes the useless "libssh2_NB_state_created" read state.
Some rotted comments have also been updated.
Signed-off-by: Salvador <sfandino@yahoo.com>
Until now, the window size (channel->remote.window_size) was being
updated just after receiving the packet from the transport layer.
That behaviour is wrong because the channel queue may grow uncontrolled
when data arrives from the network faster that the upper layer consumes
it.
This patch adds a new counter, read_avail, which keeps a count of the
bytes available from the packet queue for reading. Also, now the window
size is adjusted when the data is actually read by an upper layer.
That way, if the upper layer stops reading data, the window will
eventually fill and the remote host will stop sending data. When the
upper layers reads enough data, a window adjust packet is delivered and
the transfer resumes.
The read_avail counter is used to detect the situation when the remote
server tries to send data surpassing the window size. In that case, the
extra data is discarded.
Signed-off-by: Salvador <sfandino@yahoo.com>
libssh2 used to explicitly check for libgcrypt and default to OpenSSL.
Now all possible crypto libraries are checked for explicitly, making
the addition of further crypto libraries both simpler and cleaner.
Fixes issue arising when server does not support statfvs and or fstatvfs
extensions. sftp_statvfs() and sftp_fstatvfs() after this patch will
handle the case when SSH_FXP_STATUS is returned from server.
This partially reverts commit 03ca902075
in order to fix extreme slowdown when uploading to localhost via SFTP.
I was able to repeat the issue on RHEL-7 on localhost only. It did not
occur when uploading via network and it did not occur on a RHEL-6 box
with the same version of libssh2.
The problem was that sftp_read() used a read-ahead logic to figure out
the window_size, but sftp_packet_read() called indirectly from
sftp_write() did not use any read-ahead logic.
When there's no window to "write to", there's no point in waiting for
the socket to become writable since it most likely just will continue to
be.
Patch-by: ncm
Fixes#258
In _libssh2_packet_add, called by _libssh2_packet_read, a call to
_libssh2_packet_send that is supposed to send a one-byte message
SSH_MSG_REQUEST_FAILURE would send an uninitialized byte upon re-entry
if its call to _send returns _EAGAIN.
Fixes#259
The new libssh2_sftp_fsync API causes data and metadata in the
currently open file to be committed to disk at the server.
This is an OpenSSH extension to the SFTP protocol. See:
https://bugzilla.mindrot.org/show_bug.cgi?id=1798
... in macro parameters to avoid compiler warnings about lost precision.
Several macros in libssh2.h call strlen and pass the result directly to
unsigned int parameters of other functions, which warns about precision
loss because strlen returns size_t which is unsigned long on at least
some platforms (such as OS X). The fix is to simply typecast the
strlen() result to unsigned int.
libssh2_knownhost_readfile() silently ignored problems when reading keys
in unsupported formats from the known hosts file. When the file is
written again from the internal structures of libssh2 it gets truntcated
to the point where the first unknown key was located.
* src/knownhost.c:libssh2_knownhost_readfile() - return error if key
parsing fails
Add a "use_in_auth" flag to the LIBSSH2_COMP_METHOD struct and a
separate "zlib@openssh.com" method, along with checking session->state
for LIBSSH2_STATE_AUTHENTICATED. Appears to work on the OpenSSH servers
I've tried against, and it should work as before with normal zlib
compression.
