The curl does not do any (or enough) chunking when writing large files using the
sftp_write() function which causes some servers to choke [1]. The simplest
solution is to limit the SFTP packet size according the SFTP specification
recommendation which is 32768 B and not write more.
This means the function will not write the whole amount of data it was asked to
write and the calling applications are required to handle the return values
correctly.
More complicated solution would be to send several SFTP packet from the single
sftp_write() function by iterating over the all data passed.
The next improvement in the long term should be respecting the value reported by
the server in the limits@openssh.com extension, which specifies the maximum
packet size and reads/writes explicitly (if supported).
[1] https://github.com/curl/curl/pull/11804
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Some architectures (s390x) provide different poll events such as POLLHUP in case
the remote end closed the connection (and they keep reporting this forever).
This is an issue when the user provided callback registering this event as an
error and tries to send some reply (for example EOF) using
`ssh_channel_send_eof()` which will lead to infinite recursion and sefgaults.
This was not solved by the 30b5a2e33b because the
POLLHUP event is not provided by the poll in events bitfield, but only reported
by the poll in revents bit field thus we need to filter these events later on
when the poll is recursively.
Fixes#202
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
The FD locking was modified in 30b5a2e33b but it
caused some weird issues on s390x in Debian tests, which were getting POLLHUP,
causing infinite recursion while the callback tried to close socket.
Previously, the lock blocked only the POLLIN events as we believed these were
the only events we could get recursively that could cause issues. But it looks
like more sane behavior will be blocking everything but POLLOUT to allow the
buffers to be flushed.
Fixes#202
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
The window size controls how much data the peer can send before
we send back a message to to increase the window.
This changes the default window from 1.28MB to 2MiB. 2MiB matches
the OpenSSH default session size.
The code is also refactored to grow the windows on code paths
where data is consumed, and move the condition that checks
if the growing the window is needed into the grow method.
Signed-off-by: Tom Deseyn <tom.deseyn@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
The intention is that this releases memory allocated by the crypto
library, for functions like bignum_bn2hex() and bignum_bn2dec().
Consequently, ssh_gcry_bn2dec and ssh_mbedcry_bn2num should use
gcry_malloc() and mbedtls_calloc() respectively to allocate
memory since it will/should be released by ssh_crypto_free() so
that the internal APIs are consistent between crypto libraries.
Signed-off-by: Simon Josefsson <simon@josefsson.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
A call to write() may perform a short write on a local file.
To avoid short writes, ssh_writen() can be used.
Signed-off-by: Eshan Kelkar <eshankelkar@galorithm.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Norbert Pocs <npocs@redhat.com>
A call to read() may peform a short read from a local file even when
sufficient data is present in the file. ssh_readn() can be used
instead of read() to avoid such short reads.
Signed-off-by: Eshan Kelkar <eshankelkar@galorithm.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Norbert Pocs <npocs@redhat.com>
This aligns it with libgcrypt/OpenSSL backends which uses char*.
It also aligns mbedcrypto's bignum_bn2hex() to use an unsigned
cast just like OpenSSL backend.
Signed-off-by: Simon Josefsson <simon@josefsson.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
assume stderr by default and log only warning in case the data type is
non-standard.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Sahana Prasad <sahana@redhat.com>
Reviewed-by: Norbert Pocs <npocs@redhat.com>
Compatibility code for mapping open, read, write, close and unlink
to _open, _read, _write, _close and _unlink respectively on Windows
was repeated in a lot of .c files.
This commit adds that compatibility code to include/libssh/priv.h
and removes it from the .c files (while ensuring that those .c
files include priv.h) so that the compatibility code stays in one
place, can be maintained easily and can be added easily to another
source file by including priv.h in that file.
Signed-off-by: Eshan Kelkar <eshankelkar@galorithm.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Originally reported by Wei Chong Tan <shellcurity at protonmail.com>
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Norbert Pocs <npocs@redhat.com>
... to better describe the function, which is only replying to the client with
our version and extensions.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
These can be replaced by user-provided functions when needed.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
