1 /***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at https://curl.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 * SPDX-License-Identifier: curl AND ISC
22 *
23 ***************************************************************************/
24
25 #include "curl_setup.h"
26
27 #if defined(USE_SSH)
28
29 #include <curl/curl.h>
30 #include "curl_memory.h"
31 #include "curl_path.h"
32 #include "escape.h"
33 #include "memdebug.h"
34
35 #define MAX_SSHPATH_LEN 100000 /* arbitrary */
36
37 /* figure out the path to work with in this particular request */
Curl_getworkingpath(struct Curl_easy * data,char * homedir,char ** path)38 CURLcode Curl_getworkingpath(struct Curl_easy *data,
39 char *homedir, /* when SFTP is used */
40 char **path) /* returns the allocated
41 real path to work with */
42 {
43 char *working_path;
44 size_t working_path_len;
45 struct dynbuf npath;
46 CURLcode result =
47 Curl_urldecode(data->state.up.path, 0, &working_path,
48 &working_path_len, REJECT_ZERO);
49 if(result)
50 return result;
51
52 /* new path to switch to in case we need to */
53 Curl_dyn_init(&npath, MAX_SSHPATH_LEN);
54
55 /* Check for /~/, indicating relative to the user's home directory */
56 if((data->conn->handler->protocol & CURLPROTO_SCP) &&
57 (working_path_len > 3) && (!memcmp(working_path, "/~/", 3))) {
58 /* It is referenced to the home directory, so strip the leading '/~/' */
59 if(Curl_dyn_addn(&npath, &working_path[3], working_path_len - 3)) {
60 free(working_path);
61 return CURLE_OUT_OF_MEMORY;
62 }
63 }
64 else if((data->conn->handler->protocol & CURLPROTO_SFTP) &&
65 (!strcmp("/~", working_path) ||
66 ((working_path_len > 2) && !memcmp(working_path, "/~/", 3)))) {
67 if(Curl_dyn_add(&npath, homedir)) {
68 free(working_path);
69 return CURLE_OUT_OF_MEMORY;
70 }
71 if(working_path_len > 2) {
72 size_t len;
73 const char *p;
74 int copyfrom = 3;
75 /* Copy a separating '/' if homedir does not end with one */
76 len = Curl_dyn_len(&npath);
77 p = Curl_dyn_ptr(&npath);
78 if(len && (p[len-1] != '/'))
79 copyfrom = 2;
80
81 if(Curl_dyn_addn(&npath,
82 &working_path[copyfrom], working_path_len - copyfrom)) {
83 free(working_path);
84 return CURLE_OUT_OF_MEMORY;
85 }
86 }
87 }
88
89 if(Curl_dyn_len(&npath)) {
90 free(working_path);
91
92 /* store the pointer for the caller to receive */
93 *path = Curl_dyn_ptr(&npath);
94 }
95 else
96 *path = working_path;
97
98 return CURLE_OK;
99 }
100
101 /* The get_pathname() function is being borrowed from OpenSSH sftp.c
102 version 4.6p1. */
103 /*
104 * Copyright (c) 2001-2004 Damien Miller <djm@openbsd.org>
105 *
106 * Permission to use, copy, modify, and distribute this software for any
107 * purpose with or without fee is hereby granted, provided that the above
108 * copyright notice and this permission notice appear in all copies.
109 *
110 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
111 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
112 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
113 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
114 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
115 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
116 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
117 */
Curl_get_pathname(const char ** cpp,char ** path,char * homedir)118 CURLcode Curl_get_pathname(const char **cpp, char **path, char *homedir)
119 {
120 const char *cp = *cpp, *end;
121 char quot;
122 unsigned int i, j;
123 size_t fullPathLength, pathLength;
124 bool relativePath = false;
125 static const char WHITESPACE[] = " \t\r\n";
126
127 DEBUGASSERT(homedir);
128 if(!*cp || !homedir) {
129 *cpp = NULL;
130 *path = NULL;
131 return CURLE_QUOTE_ERROR;
132 }
133 /* Ignore leading whitespace */
134 cp += strspn(cp, WHITESPACE);
135 /* Allocate enough space for home directory and filename + separator */
136 fullPathLength = strlen(cp) + strlen(homedir) + 2;
137 *path = malloc(fullPathLength);
138 if(!*path)
139 return CURLE_OUT_OF_MEMORY;
140
141 /* Check for quoted filenames */
142 if(*cp == '\"' || *cp == '\'') {
143 quot = *cp++;
144
145 /* Search for terminating quote, unescape some chars */
146 for(i = j = 0; i <= strlen(cp); i++) {
147 if(cp[i] == quot) { /* Found quote */
148 i++;
149 (*path)[j] = '\0';
150 break;
151 }
152 if(cp[i] == '\0') { /* End of string */
153 goto fail;
154 }
155 if(cp[i] == '\\') { /* Escaped characters */
156 i++;
157 if(cp[i] != '\'' && cp[i] != '\"' &&
158 cp[i] != '\\') {
159 goto fail;
160 }
161 }
162 (*path)[j++] = cp[i];
163 }
164
165 if(j == 0) {
166 goto fail;
167 }
168 *cpp = cp + i + strspn(cp + i, WHITESPACE);
169 }
170 else {
171 /* Read to end of filename - either to whitespace or terminator */
172 end = strpbrk(cp, WHITESPACE);
173 if(!end)
174 end = strchr(cp, '\0');
175 /* return pointer to second parameter if it exists */
176 *cpp = end + strspn(end, WHITESPACE);
177 pathLength = 0;
178 relativePath = (cp[0] == '/' && cp[1] == '~' && cp[2] == '/');
179 /* Handling for relative path - prepend home directory */
180 if(relativePath) {
181 strcpy(*path, homedir);
182 pathLength = strlen(homedir);
183 (*path)[pathLength++] = '/';
184 (*path)[pathLength] = '\0';
185 cp += 3;
186 }
187 /* Copy path name up until first "whitespace" */
188 memcpy(&(*path)[pathLength], cp, (int)(end - cp));
189 pathLength += (int)(end - cp);
190 (*path)[pathLength] = '\0';
191 }
192 return CURLE_OK;
193
194 fail:
195 Curl_safefree(*path);
196 return CURLE_QUOTE_ERROR;
197 }
198
199 #endif /* if SSH is used */
200
