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
22 *
23 ***************************************************************************/
24 #include "tool_setup.h"
25
26 #define ENABLE_CURLX_PRINTF
27 /* use our own printf() functions */
28 #include "curlx.h"
29 #include "dynbuf.h"
30
31 #include "tool_cfgable.h"
32 #include "tool_msgs.h"
33 #include "tool_ipfs.h"
34
35 #include "memdebug.h" /* keep this as LAST include */
36
37 /* ensure input ends in slash */
ensure_trailing_slash(char ** input)38 static CURLcode ensure_trailing_slash(char **input)
39 {
40 if(*input && **input) {
41 size_t len = strlen(*input);
42 if(((*input)[len - 1] != '/')) {
43 struct curlx_dynbuf dyn;
44 curlx_dyn_init(&dyn, len + 2);
45
46 if(curlx_dyn_addn(&dyn, *input, len)) {
47 Curl_safefree(*input);
48 return CURLE_OUT_OF_MEMORY;
49 }
50
51 Curl_safefree(*input);
52
53 if(curlx_dyn_addn(&dyn, "/", 1))
54 return CURLE_OUT_OF_MEMORY;
55
56 *input = curlx_dyn_ptr(&dyn);
57 }
58 }
59
60 return CURLE_OK;
61 }
62
ipfs_gateway(void)63 static char *ipfs_gateway(void)
64 {
65 char *ipfs_path = NULL;
66 char *gateway_composed_file_path = NULL;
67 FILE *gateway_file = NULL;
68 char *gateway = curl_getenv("IPFS_GATEWAY");
69
70 /* Gateway is found from environment variable. */
71 if(gateway) {
72 if(ensure_trailing_slash(&gateway))
73 goto fail;
74 return gateway;
75 }
76
77 /* Try to find the gateway in the IPFS data folder. */
78 ipfs_path = curl_getenv("IPFS_PATH");
79
80 if(!ipfs_path) {
81 char *home = getenv("HOME");
82 if(home && *home)
83 ipfs_path = aprintf("%s/.ipfs/", home);
84 /* fallback to "~/.ipfs", as that's the default location. */
85 }
86
87 if(!ipfs_path || ensure_trailing_slash(&ipfs_path))
88 goto fail;
89
90 gateway_composed_file_path = aprintf("%sgateway", ipfs_path);
91
92 if(!gateway_composed_file_path)
93 goto fail;
94
95 gateway_file = fopen(gateway_composed_file_path, FOPEN_READTEXT);
96 Curl_safefree(gateway_composed_file_path);
97
98 if(gateway_file) {
99 int c;
100 struct curlx_dynbuf dyn;
101 curlx_dyn_init(&dyn, MAX_GATEWAY_URL_LEN);
102
103 /* get the first line of the gateway file, ignore the rest */
104 while((c = getc(gateway_file)) != EOF && c != '\n' && c != '\r') {
105 char c_char = (char)c;
106 if(curlx_dyn_addn(&dyn, &c_char, 1))
107 goto fail;
108 }
109
110 fclose(gateway_file);
111 gateway_file = NULL;
112
113 if(curlx_dyn_len(&dyn))
114 gateway = curlx_dyn_ptr(&dyn);
115
116 if(gateway)
117 ensure_trailing_slash(&gateway);
118
119 if(!gateway)
120 goto fail;
121
122 Curl_safefree(ipfs_path);
123
124 return gateway;
125 }
126 fail:
127 if(gateway_file)
128 fclose(gateway_file);
129 Curl_safefree(gateway);
130 Curl_safefree(ipfs_path);
131 return NULL;
132 }
133
134 /*
135 * Rewrite ipfs://<cid> and ipns://<cid> to a HTTP(S)
136 * URL that can be handled by an IPFS gateway.
137 */
ipfs_url_rewrite(CURLU * uh,const char * protocol,char ** url,struct OperationConfig * config)138 CURLcode ipfs_url_rewrite(CURLU *uh, const char *protocol, char **url,
139 struct OperationConfig *config)
140 {
141 CURLcode result = CURLE_URL_MALFORMAT;
142 CURLUcode getResult;
143 char *gateway = NULL;
144 char *gwhost = NULL;
145 char *gwpath = NULL;
146 char *gwquery = NULL;
147 char *gwscheme = NULL;
148 char *gwport = NULL;
149 char *inputpath = NULL;
150 char *cid = NULL;
151 char *pathbuffer = NULL;
152 char *cloneurl;
153 CURLU *gatewayurl = curl_url();
154
155 if(!gatewayurl) {
156 result = CURLE_FAILED_INIT;
157 goto clean;
158 }
159
160 getResult = curl_url_get(uh, CURLUPART_HOST, &cid, CURLU_URLDECODE);
161 if(getResult || !cid)
162 goto clean;
163
164 /* We might have a --ipfs-gateway argument. Check it first and use it. Error
165 * if we do have something but if it's an invalid url.
166 */
167 if(config->ipfs_gateway) {
168 /* ensure the gateway ends in a trailing / */
169 if(ensure_trailing_slash(&config->ipfs_gateway) != CURLE_OK) {
170 result = CURLE_OUT_OF_MEMORY;
171 goto clean;
172 }
173
174 if(!curl_url_set(gatewayurl, CURLUPART_URL, config->ipfs_gateway,
175 CURLU_GUESS_SCHEME)) {
176 gateway = strdup(config->ipfs_gateway);
177 if(!gateway) {
178 result = CURLE_URL_MALFORMAT;
179 goto clean;
180 }
181
182 }
183 else {
184 result = CURLE_BAD_FUNCTION_ARGUMENT;
185 goto clean;
186 }
187 }
188 else {
189 /* this is ensured to end in a trailing / within ipfs_gateway() */
190 gateway = ipfs_gateway();
191 if(!gateway) {
192 result = CURLE_FILE_COULDNT_READ_FILE;
193 goto clean;
194 }
195
196 if(curl_url_set(gatewayurl, CURLUPART_URL, gateway, 0)) {
197 result = CURLE_URL_MALFORMAT;
198 goto clean;
199 }
200 }
201
202 /* check for unsupported gateway parts */
203 if(curl_url_get(gatewayurl, CURLUPART_QUERY, &gwquery, 0)
204 != CURLUE_NO_QUERY) {
205 result = CURLE_URL_MALFORMAT;
206 goto clean;
207 }
208
209 /* get gateway parts */
210 if(curl_url_get(gatewayurl, CURLUPART_HOST,
211 &gwhost, CURLU_URLDECODE)) {
212 goto clean;
213 }
214
215 if(curl_url_get(gatewayurl, CURLUPART_SCHEME,
216 &gwscheme, CURLU_URLDECODE)) {
217 goto clean;
218 }
219
220 curl_url_get(gatewayurl, CURLUPART_PORT, &gwport, CURLU_URLDECODE);
221 curl_url_get(gatewayurl, CURLUPART_PATH, &gwpath, CURLU_URLDECODE);
222
223 /* get the path from user input */
224 curl_url_get(uh, CURLUPART_PATH, &inputpath, CURLU_URLDECODE);
225 /* inputpath might be NULL or a valid pointer now */
226
227 /* set gateway parts in input url */
228 if(curl_url_set(uh, CURLUPART_SCHEME, gwscheme, CURLU_URLENCODE) ||
229 curl_url_set(uh, CURLUPART_HOST, gwhost, CURLU_URLENCODE) ||
230 curl_url_set(uh, CURLUPART_PORT, gwport, CURLU_URLENCODE))
231 goto clean;
232
233 /* if the input path is just a slash, clear it */
234 if(inputpath && (inputpath[0] == '/') && !inputpath[1])
235 *inputpath = '\0';
236
237 /* ensure the gateway path ends with a trailing slash */
238 ensure_trailing_slash(&gwpath);
239
240 pathbuffer = aprintf("%s%s/%s%s", gwpath, protocol, cid,
241 inputpath ? inputpath : "");
242 if(!pathbuffer) {
243 goto clean;
244 }
245
246 if(curl_url_set(uh, CURLUPART_PATH, pathbuffer, CURLU_URLENCODE)) {
247 goto clean;
248 }
249
250 /* Free whatever it has now, rewriting is next */
251 Curl_safefree(*url);
252
253 if(curl_url_get(uh, CURLUPART_URL, &cloneurl, CURLU_URLENCODE)) {
254 goto clean;
255 }
256 /* we need to strdup the URL so that we can call free() on it later */
257 *url = strdup(cloneurl);
258 curl_free(cloneurl);
259 if(!*url)
260 goto clean;
261
262 result = CURLE_OK;
263
264 clean:
265 free(gateway);
266 curl_free(gwhost);
267 curl_free(gwpath);
268 curl_free(gwquery);
269 curl_free(inputpath);
270 curl_free(gwscheme);
271 curl_free(gwport);
272 curl_free(cid);
273 curl_free(pathbuffer);
274 curl_url_cleanup(gatewayurl);
275 {
276 switch(result) {
277 case CURLE_URL_MALFORMAT:
278 helpf(tool_stderr, "malformed target URL");
279 break;
280 case CURLE_FILE_COULDNT_READ_FILE:
281 helpf(tool_stderr, "IPFS automatic gateway detection failed");
282 break;
283 case CURLE_BAD_FUNCTION_ARGUMENT:
284 helpf(tool_stderr, "--ipfs-gateway was given a malformed URL");
285 break;
286 default:
287 break;
288 }
289 }
290 return result;
291 }
292
