1 /*
2 * Copyright 2001-2023 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10 #include <stdio.h> /* for sscanf() */
11 #include <string.h>
12 #include <openssl/http.h>
13 #include <openssl/httperr.h>
14 #include <openssl/bio.h> /* for BIO_snprintf() */
15 #include <openssl/err.h>
16 #include "internal/cryptlib.h" /* for ossl_assert() */
17 #ifndef OPENSSL_NO_SOCK
18 # include "internal/bio_addr.h" /* for NI_MAXHOST */
19 #endif
20 #ifndef NI_MAXHOST
21 # define NI_MAXHOST 255
22 #endif
23 #include "crypto/ctype.h" /* for ossl_isspace() */
24
init_pstring(char ** pstr)25 static void init_pstring(char **pstr)
26 {
27 if (pstr != NULL) {
28 *pstr = NULL;
29 }
30 }
31
init_pint(int * pint)32 static void init_pint(int *pint)
33 {
34 if (pint != NULL) {
35 *pint = 0;
36 }
37 }
38
copy_substring(char ** dest,const char * start,const char * end)39 static int copy_substring(char **dest, const char *start, const char *end)
40 {
41 return dest == NULL
42 || (*dest = OPENSSL_strndup(start, end - start)) != NULL;
43 }
44
free_pstring(char ** pstr)45 static void free_pstring(char **pstr)
46 {
47 if (pstr != NULL) {
48 OPENSSL_free(*pstr);
49 *pstr = NULL;
50 }
51 }
52
OSSL_parse_url(const char * url,char ** pscheme,char ** puser,char ** phost,char ** pport,int * pport_num,char ** ppath,char ** pquery,char ** pfrag)53 int OSSL_parse_url(const char *url, char **pscheme, char **puser, char **phost,
54 char **pport, int *pport_num,
55 char **ppath, char **pquery, char **pfrag)
56 {
57 const char *p, *tmp;
58 const char *scheme, *scheme_end;
59 const char *user, *user_end;
60 const char *host, *host_end;
61 const char *port, *port_end;
62 unsigned int portnum;
63 const char *path, *path_end;
64 const char *query, *query_end;
65 const char *frag, *frag_end;
66
67 init_pstring(pscheme);
68 init_pstring(puser);
69 init_pstring(phost);
70 init_pstring(pport);
71 init_pint(pport_num);
72 init_pstring(ppath);
73 init_pstring(pfrag);
74 init_pstring(pquery);
75
76 if (url == NULL) {
77 ERR_raise(ERR_LIB_HTTP, ERR_R_PASSED_NULL_PARAMETER);
78 return 0;
79 }
80
81 /* check for optional prefix "<scheme>://" */
82 scheme = scheme_end = url;
83 p = strstr(url, "://");
84 if (p == NULL) {
85 p = url;
86 } else {
87 scheme_end = p;
88 if (scheme_end == scheme)
89 goto parse_err;
90 p += strlen("://");
91 }
92
93 /* parse optional "userinfo@" */
94 user = user_end = host = p;
95 host = strchr(p, '@');
96 if (host != NULL)
97 user_end = host++;
98 else
99 host = p;
100
101 /* parse hostname/address as far as needed here */
102 if (host[0] == '[') {
103 /* IPv6 literal, which may include ':' */
104 host_end = strchr(host + 1, ']');
105 if (host_end == NULL)
106 goto parse_err;
107 p = ++host_end;
108 } else {
109 /* look for start of optional port, path, query, or fragment */
110 host_end = strchr(host, ':');
111 if (host_end == NULL)
112 host_end = strchr(host, '/');
113 if (host_end == NULL)
114 host_end = strchr(host, '?');
115 if (host_end == NULL)
116 host_end = strchr(host, '#');
117 if (host_end == NULL) /* the remaining string is just the hostname */
118 host_end = host + strlen(host);
119 p = host_end;
120 }
121
122 /* parse optional port specification starting with ':' */
123 port = "0"; /* default */
124 if (*p == ':')
125 port = ++p;
126 /* remaining port spec handling is also done for the default values */
127 /* make sure a decimal port number is given */
128 if (sscanf(port, "%u", &portnum) <= 0 || portnum > 65535) {
129 ERR_raise_data(ERR_LIB_HTTP, HTTP_R_INVALID_PORT_NUMBER, "%s", port);
130 goto err;
131 }
132 for (port_end = port; '0' <= *port_end && *port_end <= '9'; port_end++)
133 ;
134 if (port == p) /* port was given explicitly */
135 p += port_end - port;
136
137 /* check for optional path starting with '/' or '?'. Else must start '#' */
138 path = p;
139 if (*path != '\0' && *path != '/' && *path != '?' && *path != '#') {
140 ERR_raise(ERR_LIB_HTTP, HTTP_R_INVALID_URL_PATH);
141 goto parse_err;
142 }
143 path_end = query = query_end = frag = frag_end = path + strlen(path);
144
145 /* parse optional "?query" */
146 tmp = strchr(p, '?');
147 if (tmp != NULL) {
148 p = tmp;
149 if (pquery != NULL) {
150 path_end = p;
151 query = p + 1;
152 }
153 }
154
155 /* parse optional "#fragment" */
156 tmp = strchr(p, '#');
157 if (tmp != NULL) {
158 if (query == path_end) /* we did not record a query component */
159 path_end = tmp;
160 query_end = tmp;
161 frag = tmp + 1;
162 }
163
164 if (!copy_substring(pscheme, scheme, scheme_end)
165 || !copy_substring(phost, host, host_end)
166 || !copy_substring(pport, port, port_end)
167 || !copy_substring(puser, user, user_end)
168 || !copy_substring(pquery, query, query_end)
169 || !copy_substring(pfrag, frag, frag_end))
170 goto err;
171 if (pport_num != NULL)
172 *pport_num = (int)portnum;
173 if (*path == '/') {
174 if (!copy_substring(ppath, path, path_end))
175 goto err;
176 } else if (ppath != NULL) { /* must prepend '/' */
177 size_t buflen = 1 + path_end - path + 1;
178
179 if ((*ppath = OPENSSL_malloc(buflen)) == NULL)
180 goto err;
181 BIO_snprintf(*ppath, buflen, "/%s", path);
182 }
183 return 1;
184
185 parse_err:
186 ERR_raise(ERR_LIB_HTTP, HTTP_R_ERROR_PARSING_URL);
187
188 err:
189 free_pstring(pscheme);
190 free_pstring(puser);
191 free_pstring(phost);
192 free_pstring(pport);
193 free_pstring(ppath);
194 free_pstring(pquery);
195 free_pstring(pfrag);
196 return 0;
197 }
198
OSSL_HTTP_parse_url(const char * url,int * pssl,char ** puser,char ** phost,char ** pport,int * pport_num,char ** ppath,char ** pquery,char ** pfrag)199 int OSSL_HTTP_parse_url(const char *url, int *pssl, char **puser, char **phost,
200 char **pport, int *pport_num,
201 char **ppath, char **pquery, char **pfrag)
202 {
203 char *scheme, *port;
204 int ssl = 0, portnum;
205
206 init_pstring(pport);
207 if (pssl != NULL)
208 *pssl = 0;
209 if (!OSSL_parse_url(url, &scheme, puser, phost, &port, pport_num,
210 ppath, pquery, pfrag))
211 return 0;
212
213 /* check for optional HTTP scheme "http[s]" */
214 if (strcmp(scheme, OSSL_HTTPS_NAME) == 0) {
215 ssl = 1;
216 if (pssl != NULL)
217 *pssl = ssl;
218 } else if (*scheme != '\0' && strcmp(scheme, OSSL_HTTP_NAME) != 0) {
219 ERR_raise(ERR_LIB_HTTP, HTTP_R_INVALID_URL_SCHEME);
220 OPENSSL_free(scheme);
221 OPENSSL_free(port);
222 goto err;
223 }
224 OPENSSL_free(scheme);
225
226 if (strcmp(port, "0") == 0) {
227 /* set default port */
228 OPENSSL_free(port);
229 port = ssl ? OSSL_HTTPS_PORT : OSSL_HTTP_PORT;
230 if (!ossl_assert(sscanf(port, "%d", &portnum) == 1))
231 goto err;
232 if (pport_num != NULL)
233 *pport_num = portnum;
234 if (pport != NULL) {
235 *pport = OPENSSL_strdup(port);
236 if (*pport == NULL)
237 goto err;
238 }
239 } else {
240 if (pport != NULL)
241 *pport = port;
242 else
243 OPENSSL_free(port);
244 }
245 return 1;
246
247 err:
248 free_pstring(puser);
249 free_pstring(phost);
250 free_pstring(ppath);
251 free_pstring(pquery);
252 free_pstring(pfrag);
253 return 0;
254 }
255
256 /* Respect no_proxy, taking default value from environment variable(s) */
use_proxy(const char * no_proxy,const char * server)257 static int use_proxy(const char *no_proxy, const char *server)
258 {
259 size_t sl;
260 const char *found = NULL;
261 char host[NI_MAXHOST];
262
263 if (!ossl_assert(server != NULL))
264 return 0;
265 sl = strlen(server);
266 if (sl >= 2 && sl < sizeof(host) + 2 && server[0] == '[' && server[sl - 1] == ']') {
267 /* strip leading '[' and trailing ']' from escaped IPv6 address */
268 sl -= 2;
269 strncpy(host, server + 1, sl);
270 server = host;
271 }
272
273 /*
274 * using environment variable names, both lowercase and uppercase variants,
275 * compatible with other HTTP client implementations like wget, curl and git
276 */
277 if (no_proxy == NULL)
278 no_proxy = ossl_safe_getenv("no_proxy");
279 if (no_proxy == NULL)
280 no_proxy = ossl_safe_getenv(OPENSSL_NO_PROXY);
281
282 if (no_proxy != NULL)
283 found = strstr(no_proxy, server);
284 while (found != NULL
285 && ((found != no_proxy && !ossl_isspace(found[-1]) && found[-1] != ',')
286 || (found[sl] != '\0' && !ossl_isspace(found[sl]) && found[sl] != ',')))
287 found = strstr(found + 1, server);
288 return found == NULL;
289 }
290
291 /* Take default value from environment variable(s), respect no_proxy */
OSSL_HTTP_adapt_proxy(const char * proxy,const char * no_proxy,const char * server,int use_ssl)292 const char *OSSL_HTTP_adapt_proxy(const char *proxy, const char *no_proxy,
293 const char *server, int use_ssl)
294 {
295 /*
296 * using environment variable names, both lowercase and uppercase variants,
297 * compatible with other HTTP client implementations like wget, curl and git
298 */
299 if (proxy == NULL)
300 proxy = ossl_safe_getenv(use_ssl ? "https_proxy" : "http_proxy");
301 if (proxy == NULL)
302 proxy = ossl_safe_getenv(use_ssl ? OPENSSL_HTTP_PROXY : OPENSSL_HTTPS_PROXY);
303
304 if (proxy == NULL || *proxy == '\0' || !use_proxy(no_proxy, server))
305 return NULL;
306 return proxy;
307 }
308
