1 /***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2021, 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 ***************************************************************************/
22
23 #include "curl_setup.h"
24
25 #if defined(USE_SSH)
26
27 #include <curl/curl.h>
28 #include "curl_memory.h"
29 #include "curl_path.h"
30 #include "escape.h"
31 #include "memdebug.h"
32
33 #define MAX_SSHPATH_LEN 100000 /* arbitrary */
34
35 /* figure out the path to work with in this particular request */
Curl_getworkingpath(struct Curl_easy * data,char * homedir,char ** path)36 CURLcode Curl_getworkingpath(struct Curl_easy *data,
37 char *homedir, /* when SFTP is used */
38 char **path) /* returns the allocated
39 real path to work with */
40 {
41 char *working_path;
42 size_t working_path_len;
43 struct dynbuf npath;
44 CURLcode result =
45 Curl_urldecode(data, data->state.up.path, 0, &working_path,
46 &working_path_len, REJECT_ZERO);
47 if(result)
48 return result;
49
50 /* new path to switch to in case we need to */
51 Curl_dyn_init(&npath, MAX_SSHPATH_LEN);
52
53 /* Check for /~/, indicating relative to the user's home directory */
54 if((data->conn->handler->protocol & CURLPROTO_SCP) &&
55 (working_path_len > 3) && (!memcmp(working_path, "/~/", 3))) {
56 /* It is referenced to the home directory, so strip the leading '/~/' */
57 if(Curl_dyn_addn(&npath, &working_path[3], working_path_len - 3)) {
58 free(working_path);
59 return CURLE_OUT_OF_MEMORY;
60 }
61 }
62 else if((data->conn->handler->protocol & CURLPROTO_SFTP) &&
63 (working_path_len > 2) && !memcmp(working_path, "/~/", 3)) {
64 size_t len;
65 const char *p;
66 int copyfrom = 3;
67 if(Curl_dyn_add(&npath, homedir)) {
68 free(working_path);
69 return CURLE_OUT_OF_MEMORY;
70 }
71 /* Copy a separating '/' if homedir does not end with one */
72 len = Curl_dyn_len(&npath);
73 p = Curl_dyn_ptr(&npath);
74 if(len && (p[len-1] != '/'))
75 copyfrom = 2;
76
77 if(Curl_dyn_addn(&npath,
78 &working_path[copyfrom], working_path_len - copyfrom)) {
79 free(working_path);
80 return CURLE_OUT_OF_MEMORY;
81 }
82 }
83
84 if(Curl_dyn_len(&npath)) {
85 free(working_path);
86
87 /* store the pointer for the caller to receive */
88 *path = Curl_dyn_ptr(&npath);
89 }
90 else
91 *path = working_path;
92
93 return CURLE_OK;
94 }
95
96 /* The get_pathname() function is being borrowed from OpenSSH sftp.c
97 version 4.6p1. */
98 /*
99 * Copyright (c) 2001-2004 Damien Miller <djm@openbsd.org>
100 *
101 * Permission to use, copy, modify, and distribute this software for any
102 * purpose with or without fee is hereby granted, provided that the above
103 * copyright notice and this permission notice appear in all copies.
104 *
105 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
106 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
107 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
108 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
109 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
110 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
111 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
112 */
Curl_get_pathname(const char ** cpp,char ** path,char * homedir)113 CURLcode Curl_get_pathname(const char **cpp, char **path, char *homedir)
114 {
115 const char *cp = *cpp, *end;
116 char quot;
117 unsigned int i, j;
118 size_t fullPathLength, pathLength;
119 bool relativePath = false;
120 static const char WHITESPACE[] = " \t\r\n";
121
122 if(!*cp) {
123 *cpp = NULL;
124 *path = NULL;
125 return CURLE_QUOTE_ERROR;
126 }
127 /* Ignore leading whitespace */
128 cp += strspn(cp, WHITESPACE);
129 /* Allocate enough space for home directory and filename + separator */
130 fullPathLength = strlen(cp) + strlen(homedir) + 2;
131 *path = malloc(fullPathLength);
132 if(!*path)
133 return CURLE_OUT_OF_MEMORY;
134
135 /* Check for quoted filenames */
136 if(*cp == '\"' || *cp == '\'') {
137 quot = *cp++;
138
139 /* Search for terminating quote, unescape some chars */
140 for(i = j = 0; i <= strlen(cp); i++) {
141 if(cp[i] == quot) { /* Found quote */
142 i++;
143 (*path)[j] = '\0';
144 break;
145 }
146 if(cp[i] == '\0') { /* End of string */
147 /*error("Unterminated quote");*/
148 goto fail;
149 }
150 if(cp[i] == '\\') { /* Escaped characters */
151 i++;
152 if(cp[i] != '\'' && cp[i] != '\"' &&
153 cp[i] != '\\') {
154 /*error("Bad escaped character '\\%c'",
155 cp[i]);*/
156 goto fail;
157 }
158 }
159 (*path)[j++] = cp[i];
160 }
161
162 if(j == 0) {
163 /*error("Empty quotes");*/
164 goto fail;
165 }
166 *cpp = cp + i + strspn(cp + i, WHITESPACE);
167 }
168 else {
169 /* Read to end of filename - either to whitespace or terminator */
170 end = strpbrk(cp, WHITESPACE);
171 if(!end)
172 end = strchr(cp, '\0');
173 /* return pointer to second parameter if it exists */
174 *cpp = end + strspn(end, WHITESPACE);
175 pathLength = 0;
176 relativePath = (cp[0] == '/' && cp[1] == '~' && cp[2] == '/');
177 /* Handling for relative path - prepend home directory */
178 if(relativePath) {
179 strcpy(*path, homedir);
180 pathLength = strlen(homedir);
181 (*path)[pathLength++] = '/';
182 (*path)[pathLength] = '\0';
183 cp += 3;
184 }
185 /* Copy path name up until first "whitespace" */
186 memcpy(&(*path)[pathLength], cp, (int)(end - cp));
187 pathLength += (int)(end - cp);
188 (*path)[pathLength] = '\0';
189 }
190 return CURLE_OK;
191
192 fail:
193 Curl_safefree(*path);
194 return CURLE_QUOTE_ERROR;
195 }
196
197 #endif /* if SSH is used */
198