sftp server implementation :)

at this time, basic support of opendir, readdir, lstat, etc.
just enough to "sftp" in and type ls.


git-svn-id: svn+ssh://svn.berlios.de/svnroot/repos/libssh/trunk@16 7dcaeef0-15fb-0310-b436-a5af3365683c

1 files changed, 244 insertions, 0 deletions

diff --git a/libssh/sftpserver.c b/libssh/sftpserver.c
new file mode 100644
index 00000000..fd759a12
--- /dev/null
+++ b/libssh/sftpserver.c
@@ -0,0 +1,244 @@
+/* sftpserver.c contains server based function for the sftp protocol */
+/*
+Copyright 2005 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/libssh.h"
+#include "libssh/sftp.h"
+#include "libssh/ssh2.h"
+#include "libssh/priv.h"
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <netdb.h>
+
+SFTP_CLIENT_MESSAGE *sftp_get_client_message(SFTP_SESSION *sftp){
+    SFTP_PACKET *packet=sftp_packet_read(sftp);
+    SFTP_CLIENT_MESSAGE *msg=malloc(sizeof (SFTP_CLIENT_MESSAGE));
+    BUFFER *payload;
+    STRING *tmp;
+    memset(msg,0,sizeof(SFTP_CLIENT_MESSAGE));
+    if(!packet)
+        return NULL;
+    payload=packet->payload;
+    ssh_say(2,"received sftp packet type %d\n",packet->type);
+    msg->type=packet->type;
+    msg->sftp=sftp;
+    buffer_get_u32(payload,&msg->id);
+    switch(msg->type){
+        case SSH_FXP_CLOSE:
+        case SSH_FXP_READDIR:
+            msg->handle=buffer_get_ssh_string(payload);
+            break;
+        case SSH_FXP_READ:
+            msg->handle=buffer_get_ssh_string(payload);
+            buffer_get_u64(payload,&msg->offset);
+            buffer_get_u32(payload,&msg->len);
+            break;
+        case SSH_FXP_WRITE:
+            msg->handle=buffer_get_ssh_string(payload);
+            buffer_get_u64(payload,&msg->offset);
+            msg->data=buffer_get_ssh_string(payload);
+            break;
+        case SSH_FXP_REMOVE:
+        case SSH_FXP_RMDIR:
+        case SSH_FXP_OPENDIR:
+        case SSH_FXP_READLINK:
+        case SSH_FXP_REALPATH:
+            tmp=buffer_get_ssh_string(payload);
+            msg->filename=string_to_char(tmp);
+            free(tmp);
+            break;
+        case SSH_FXP_RENAME:
+        case SSH_FXP_SYMLINK:
+            tmp=buffer_get_ssh_string(payload);
+            msg->filename=string_to_char(tmp);
+            free(tmp);
+            msg->data=buffer_get_ssh_string(payload);
+            break;
+        case SSH_FXP_MKDIR:
+        case SSH_FXP_SETSTAT:
+            tmp=buffer_get_ssh_string(payload);
+            msg->filename=string_to_char(tmp);
+            free(tmp);
+#warning attributes
+            break;
+        case SSH_FXP_FSETSTAT:
+            msg->handle=buffer_get_ssh_string(payload);
+#warning attributes
+            break;
+        case SSH_FXP_LSTAT:
+        case SSH_FXP_STAT:
+            tmp=buffer_get_ssh_string(payload);
+            msg->filename=string_to_char(tmp);
+            free(tmp);
+            if(sftp->version >3)
+                buffer_get_u32(payload,&msg->flags);
+            break;
+        case SSH_FXP_FSTAT:
+            msg->handle=buffer_get_ssh_string(payload);
+            buffer_get_u32(payload,&msg->flags);
+            break;
+        default:
+            printf("Received handled sftp message %d\n",msg->type);
+    }
+    msg->flags=ntohl(msg->flags);
+    msg->offset=ntohll(msg->offset);
+    msg->len=ntohl(msg->len);
+    sftp_packet_free(packet);
+    return msg;
+}
+
+void sftp_client_message_free(SFTP_CLIENT_MESSAGE *msg){
+    if(msg->filename)
+        free(msg->filename);
+    if(msg->data)
+        free(msg->data);
+    if(msg->attr)
+        sftp_attributes_free(msg->attr);
+    if(msg->handle)
+        free(msg->handle);
+    memset(msg,'X',sizeof(*msg));
+    free(msg);
+}
+
+int sftp_reply_name(SFTP_CLIENT_MESSAGE *msg, char *name, SFTP_ATTRIBUTES *attr){
+    BUFFER *out=buffer_new();
+    STRING *file=string_from_char(name);
+    int r;
+    buffer_add_u32(out,msg->id);
+    buffer_add_u32(out,htonl(1));
+    buffer_add_ssh_string(out,file);
+    buffer_add_ssh_string(out,file); /* the protocol is broken here between 3 & 4 */
+    free(file);
+    buffer_add_attributes(out,attr);
+    r=sftp_packet_write(msg->sftp,SSH_FXP_NAME,out);
+    buffer_free(out);
+    return r<0;
+}
+
+int sftp_reply_handle(SFTP_CLIENT_MESSAGE *msg, STRING *handle){
+    BUFFER *out=buffer_new();
+    int r;
+    buffer_add_u32(out,msg->id);
+    buffer_add_ssh_string(out,handle);
+    r=sftp_packet_write(msg->sftp,SSH_FXP_HANDLE,out);
+    buffer_free(out);
+    return r<0;
+}
+
+int sftp_reply_attr(SFTP_CLIENT_MESSAGE *msg, SFTP_ATTRIBUTES *attr){
+    BUFFER *out=buffer_new();
+    int r;
+    buffer_add_u32(out,msg->id);
+    buffer_add_attributes(out,attr);
+    r=sftp_packet_write(msg->sftp,SSH_FXP_ATTRS,out);
+    buffer_free(out);
+    return r<0;
+}
+
+int sftp_reply_names_add(SFTP_CLIENT_MESSAGE *msg, char *file, char *longname,
+        SFTP_ATTRIBUTES *attr){
+    STRING *name=string_from_char(file);
+    if(!msg->attrbuf)
+        msg->attrbuf=buffer_new();
+    buffer_add_ssh_string(msg->attrbuf,name);
+    free(name);
+    name=string_from_char(longname);
+    buffer_add_ssh_string(msg->attrbuf,name);
+    free(name);
+    buffer_add_attributes(msg->attrbuf,attr);
+    msg->attr_num++;
+    return 0;
+}
+
+int sftp_reply_names(SFTP_CLIENT_MESSAGE *msg){
+    BUFFER *out=buffer_new();
+    int r;
+    buffer_add_u32(out,msg->id);
+    buffer_add_u32(out,htonl(msg->attr_num));
+    buffer_add_data(out,buffer_get(msg->attrbuf),
+                    buffer_get_len(msg->attrbuf));
+    r=sftp_packet_write(msg->sftp,SSH_FXP_NAME,out);
+    buffer_free(out);
+    buffer_free(msg->attrbuf);
+    msg->attr_num=0;
+    msg->attrbuf=NULL;
+    return r<0;
+}
+
+    
+int sftp_reply_status(SFTP_CLIENT_MESSAGE *msg, u32 status, char *message){
+    BUFFER *out=buffer_new();
+    int r;
+    STRING *s;
+    buffer_add_u32(out,msg->id);
+    buffer_add_u32(out,htonl(status));
+    s=string_from_char(message?message:"");
+    buffer_add_ssh_string(out,s);
+    free(s);
+    buffer_add_u32(out,0); // language string 
+    r=sftp_packet_write(msg->sftp,SSH_FXP_STATUS,out);
+    buffer_free(out);
+    return r<0;
+}
+
+/* this function will return you a new handle to give the client.
+ * the function accepts an info that can be retrieved later with
+ * the handle. Care is given that a corrupted handle won't give a
+ * valid info (or worse). */
+STRING *sftp_handle_alloc(SFTP_SESSION *sftp, void *info){
+    int i;
+    u32 val;
+    STRING *ret;
+    if(!sftp->handles){
+        sftp->handles=malloc(sizeof(void *) * SFTP_HANDLES);
+        memset(sftp->handles,0,sizeof(void *)*SFTP_HANDLES);
+    }
+    for(i=0; i<SFTP_HANDLES;++i)
+        if(!sftp->handles[i])
+            break;
+    if(i==SFTP_HANDLES)
+        return NULL; // no handle available
+    val=i;
+    ret=string_new(4);
+    memcpy(ret->string,&val,sizeof(u32));
+    sftp->handles[i]=info;
+    return ret;
+}
+
+void *sftp_handle(SFTP_SESSION *sftp, STRING *handle){
+    u32 val;
+    if(!sftp->handles)
+        return NULL;
+    if(string_len(handle)!=sizeof(val))
+        return NULL;
+    memcpy(&val,handle->string,sizeof(u32));
+    if(val>SFTP_HANDLES)
+        return NULL;
+    return sftp->handles[val];
+}
+void sftp_handle_remove(SFTP_SESSION *sftp, void *handle){
+    int i;
+    for(i=0;i<SFTP_HANDLES;++i){
+        if(sftp->handles[i]==handle){
+            sftp->handles[i]=NULL;
+            break;
+        }
+    }
+}