diff options
Diffstat (limited to 'libssh/gzip.c')
| -rw-r--r-- | libssh/gzip.c | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/libssh/gzip.c b/libssh/gzip.c new file mode 100644 index 00000000..0b04f905 --- /dev/null +++ b/libssh/gzip.c @@ -0,0 +1,140 @@ +/* gzip.c */ +/* include hooks for compression of packets */ +/* +Copyright 2003 Aris Adamantiadis + +This file is part of the SSH Library + +The SSH Library is free software; you can redistribute it and/or modify +it under the terms of the GNU Lesser General Public License as published by +the Free Software Foundation; either version 2.1 of the License, or (at your +option) any later version. + +The SSH Library is distributed in the hope that it will be useful, but +WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY +or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public +License for more details. + +You should have received a copy of the GNU Lesser General Public License +along with the SSH Library; see the file COPYING. If not, write to +the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, +MA 02111-1307, USA. */ +#include "libssh/priv.h" +#ifdef HAVE_LIBZ +#undef NO_GZIP +#else +#define NO_GZIP +#endif + +#ifndef NO_GZIP +#include <zlib.h> +#include <string.h> +#define BLOCKSIZE 4092 + +static z_stream *initcompress(SSH_SESSION *session,int level){ + z_stream *stream=malloc(sizeof(z_stream)); + int status; + memset(stream,0,sizeof(z_stream)); + status=deflateInit(stream,level); + if (status!=0) + ssh_set_error(session,SSH_FATAL,"status %d inititalising zlib deflate",status); + return stream; +} + +BUFFER *gzip_compress(SSH_SESSION *session,BUFFER *source,int level){ + BUFFER *dest; + static unsigned char out_buf[BLOCKSIZE]; + void *in_ptr=buffer_get(source); + unsigned long in_size=buffer_get_len(source); + unsigned long len; + int status; + z_stream *zout=session->current_crypto->compress_out_ctx; + if(!zout) + zout=session->current_crypto->compress_out_ctx=initcompress(session,level); + dest=buffer_new(); + zout->next_out=out_buf; + zout->next_in=in_ptr; + zout->avail_in=in_size; + do { + zout->avail_out=BLOCKSIZE; + status=deflate(zout,Z_PARTIAL_FLUSH); + if(status !=0){ + ssh_set_error(session,SSH_FATAL,"status %d deflating zlib packet",status); + return NULL; + } + len=BLOCKSIZE-zout->avail_out; + buffer_add_data(dest,out_buf,len); + zout->next_out=out_buf; + } while (zout->avail_out == 0); + + return dest; +} + +int compress_buffer(SSH_SESSION *session,BUFFER *buf){ + BUFFER *dest=gzip_compress(session,buf,9); + if(!dest) + return -1; + buffer_reinit(buf); + buffer_add_data(buf,buffer_get(dest),buffer_get_len(dest)); + buffer_free(dest); + return 0; +} + +/* decompression */ + +static z_stream *initdecompress(SSH_SESSION *session){ + z_stream *stream=malloc(sizeof(z_stream)); + int status; + memset(stream,0,sizeof(z_stream)); + status=inflateInit(stream); + if (status!=0){ + ssh_set_error(session,SSH_FATAL,"Status = %d initiating inflate context !",status); + free(stream); + stream=NULL; + } + return stream; +} + +BUFFER *gzip_decompress(SSH_SESSION *session,BUFFER *source){ + BUFFER *dest; + static unsigned char out_buf[BLOCKSIZE]; + void *in_ptr=buffer_get_rest(source); + unsigned long in_size=buffer_get_rest_len(source); + unsigned long len; + int status; + z_stream *zin=session->current_crypto->compress_in_ctx; + if(!zin) + zin=session->current_crypto->compress_in_ctx=initdecompress(session); + dest=buffer_new(); + zin->next_out=out_buf; + zin->next_in=in_ptr; + zin->avail_in=in_size; + do { + zin->avail_out=BLOCKSIZE; + status=inflate(zin,Z_PARTIAL_FLUSH); + if(status !=Z_OK){ + ssh_set_error(session,SSH_FATAL,"status %d inflating zlib packet",status); + buffer_free(dest); + return NULL; + } + len=BLOCKSIZE-zin->avail_out; + buffer_add_data(dest,out_buf,len); + zin->next_out=out_buf; + } while (zin->avail_out == 0); + + return dest; +} + +int decompress_buffer(SSH_SESSION *session,BUFFER *buf){ + BUFFER *dest=gzip_decompress(session,buf); + buffer_reinit(buf); + if(!dest){ + return -1; /* failed */ + } + buffer_reinit(buf); + buffer_add_data(buf,buffer_get(dest),buffer_get_len(dest)); + buffer_free(dest); + return 0; +} + +#endif /* NO_GZIP */ |