Added support for libssh SSH SCP back-end

libssh is an alternative library to libssh2.
https://www.libssh.org/

That patch set also introduces support for ECDSA
ed25519 keys, as well as gssapi authentication.

Signed-off-by: Nikos Mavrogiannopoulos <nmav@redhat.com>

1 files changed, 179 insertions, 0 deletions

diff --git a/lib/curl_path.c b/lib/curl_path.c
new file mode 100644
index 000000000..cd6592096
--- /dev/null
+++ b/lib/curl_path.c
@@ -0,0 +1,179 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at https://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+
+#include "curl_setup.h"
+
+#include <curl/curl.h>
+#include "curl_memory.h"
+#include "curl_path.h"
+#include "escape.h"
+#include "memdebug.h"
+
+/* figure out the path to work with in this particular request */
+CURLcode Curl_getworkingpath(struct connectdata *conn,
+                             char *homedir,  /* when SFTP is used */
+                             char **path) /* returns the  allocated
+                                             real path to work with */
+{
+  struct Curl_easy *data = conn->data;
+  char *real_path = NULL;
+  char *working_path;
+  size_t working_path_len;
+  CURLcode result =
+    Curl_urldecode(data, data->state.path, 0, &working_path,
+                   &working_path_len, FALSE);
+  if(result)
+    return result;
+
+  /* Check for /~/, indicating relative to the user's home directory */
+  if(conn->handler->protocol & CURLPROTO_SCP) {
+    real_path = malloc(working_path_len + 1);
+    if(real_path == NULL) {
+      free(working_path);
+      return CURLE_OUT_OF_MEMORY;
+    }
+    if((working_path_len > 3) && (!memcmp(working_path, "/~/", 3)))
+      /* It is referenced to the home directory, so strip the leading '/~/' */
+      memcpy(real_path, working_path + 3, 4 + working_path_len-3);
+    else
+      memcpy(real_path, working_path, 1 + working_path_len);
+  }
+  else if(conn->handler->protocol & CURLPROTO_SFTP) {
+    if((working_path_len > 1) && (working_path[1] == '~')) {
+      size_t homelen = strlen(homedir);
+      real_path = malloc(homelen + working_path_len + 1);
+      if(real_path == NULL) {
+        free(working_path);
+        return CURLE_OUT_OF_MEMORY;
+      }
+      /* It is referenced to the home directory, so strip the
+         leading '/' */
+      memcpy(real_path, homedir, homelen);
+      real_path[homelen] = '/';
+      real_path[homelen + 1] = '\0';
+      if(working_path_len > 3) {
+        memcpy(real_path + homelen + 1, working_path + 3,
+               1 + working_path_len -3);
+      }
+    }
+    else {
+      real_path = malloc(working_path_len + 1);
+      if(real_path == NULL) {
+        free(working_path);
+        return CURLE_OUT_OF_MEMORY;
+      }
+      memcpy(real_path, working_path, 1 + working_path_len);
+    }
+  }
+
+  free(working_path);
+
+  /* store the pointer for the caller to receive */
+  *path = real_path;
+
+  return CURLE_OK;
+}
+
+/* The get_pathname() function is being borrowed from OpenSSH sftp.c
+   version 4.6p1. */
+/*
+ * Copyright (c) 2001-2004 Damien Miller <djm@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+CURLcode Curl_get_pathname(const char **cpp, char **path)
+{
+  const char *cp = *cpp, *end;
+  char quot;
+  unsigned int i, j;
+  static const char WHITESPACE[] = " \t\r\n";
+
+  cp += strspn(cp, WHITESPACE);
+  if(!*cp) {
+    *cpp = cp;
+    *path = NULL;
+    return CURLE_QUOTE_ERROR;
+  }
+
+  *path = malloc(strlen(cp) + 1);
+  if(*path == NULL)
+    return CURLE_OUT_OF_MEMORY;
+
+  /* Check for quoted filenames */
+  if(*cp == '\"' || *cp == '\'') {
+    quot = *cp++;
+
+    /* Search for terminating quote, unescape some chars */
+    for(i = j = 0; i <= strlen(cp); i++) {
+      if(cp[i] == quot) {  /* Found quote */
+        i++;
+        (*path)[j] = '\0';
+        break;
+      }
+      if(cp[i] == '\0') {  /* End of string */
+        /*error("Unterminated quote");*/
+        goto fail;
+      }
+      if(cp[i] == '\\') {  /* Escaped characters */
+        i++;
+        if(cp[i] != '\'' && cp[i] != '\"' &&
+            cp[i] != '\\') {
+          /*error("Bad escaped character '\\%c'",
+              cp[i]);*/
+          goto fail;
+        }
+      }
+      (*path)[j++] = cp[i];
+    }
+
+    if(j == 0) {
+      /*error("Empty quotes");*/
+      goto fail;
+    }
+    *cpp = cp + i + strspn(cp + i, WHITESPACE);
+  }
+  else {
+    /* Read to end of filename */
+    end = strpbrk(cp, WHITESPACE);
+    if(end == NULL)
+      end = strchr(cp, '\0');
+    *cpp = end + strspn(end, WHITESPACE);
+
+    memcpy(*path, cp, end - cp);
+    (*path)[end - cp] = '\0';
+  }
+  return CURLE_OK;
+
+  fail:
+  Curl_safefree(*path);
+  return CURLE_QUOTE_ERROR;
+}