xref: /freebsd/crypto/openssl/crypto/http/http_lib.c (revision 10a428653ee7216475f1ddce3fb4cbf1200319f8)
1 /*
2  * Copyright 2001-2026 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 *authority_end;
59     const char *scheme, *scheme_end;
60     const char *user, *user_end;
61     const char *host, *host_end;
62     const char *port, *port_end;
63     unsigned int portnum = 0;
64     const char *path, *path_end;
65     const char *query, *query_end;
66     const char *frag, *frag_end;
67 
68     init_pstring(pscheme);
69     init_pstring(puser);
70     init_pstring(phost);
71     init_pstring(pport);
72     init_pint(pport_num);
73     init_pstring(ppath);
74     init_pstring(pfrag);
75     init_pstring(pquery);
76 
77     if (url == NULL) {
78         ERR_raise(ERR_LIB_HTTP, ERR_R_PASSED_NULL_PARAMETER);
79         return 0;
80     }
81 
82     /* check for optional prefix "<scheme>://" */
83     scheme = scheme_end = url;
84     p = strstr(url, "://");
85     if (p == NULL) {
86         p = url;
87     } else {
88         scheme_end = p;
89         if (scheme_end == scheme)
90             goto parse_err;
91         p += strlen("://");
92     }
93 
94     /* parse optional "userinfo@" */
95     user = user_end = host = p;
96     authority_end = strpbrk(p, "/?#");
97     if (authority_end == NULL)
98         authority_end = p + strlen(p);
99     host = memchr(p, '@', authority_end - p);
100     if (host != NULL)
101         user_end = host++;
102     else
103         host = p;
104 
105     /* parse hostname/address as far as needed here */
106     if (host[0] == '[') {
107         /* IPv6 literal, which may include ':' */
108         host_end = strchr(host + 1, ']');
109         if (host_end == NULL)
110             goto parse_err;
111         p = ++host_end;
112     } else {
113         /* look for start of optional port, path, query, or fragment */
114         host_end = strpbrk(host, ":/?#");
115         if (host_end == NULL) /* the remaining string is just the hostname */
116             host_end = host + strlen(host);
117         p = host_end;
118     }
119 
120     /* parse optional port specification starting with ':' */
121     port = "0"; /* default */
122     if (*p == ':')
123         port = ++p;
124     /* remaining port spec handling is also done for the default values */
125     /* make sure a decimal port number is given */
126     if (sscanf(port, "%u", &portnum) <= 0 || portnum > 65535) {
127         ERR_raise_data(ERR_LIB_HTTP, HTTP_R_INVALID_PORT_NUMBER, "%s", port);
128         goto err;
129     }
130     for (port_end = port; '0' <= *port_end && *port_end <= '9'; port_end++)
131         ;
132     if (port == p) /* port was given explicitly */
133         p += port_end - port;
134 
135     /* check for optional path starting with '/' or '?'. Else must start '#' */
136     path = p;
137     if (*path != '\0' && *path != '/' && *path != '?' && *path != '#') {
138         ERR_raise(ERR_LIB_HTTP, HTTP_R_INVALID_URL_PATH);
139         goto parse_err;
140     }
141     path_end = query = query_end = frag = frag_end = path + strlen(path);
142 
143     /* parse optional "?query" */
144     tmp = strchr(p, '?');
145     if (tmp != NULL) {
146         p = tmp;
147         if (pquery != NULL) {
148             path_end = p;
149             query = p + 1;
150         }
151     }
152 
153     /* parse optional "#fragment" */
154     tmp = strchr(p, '#');
155     if (tmp != NULL) {
156         if (query == path_end) /* we did not record a query component */
157             path_end = tmp;
158         query_end = tmp;
159         frag = tmp + 1;
160     }
161 
162     if (!copy_substring(pscheme, scheme, scheme_end)
163         || !copy_substring(phost, host, host_end)
164         || !copy_substring(pport, port, port_end)
165         || !copy_substring(puser, user, user_end)
166         || !copy_substring(pquery, query, query_end)
167         || !copy_substring(pfrag, frag, frag_end))
168         goto err;
169     if (pport_num != NULL)
170         *pport_num = (int)portnum;
171     if (*path == '/') {
172         if (!copy_substring(ppath, path, path_end))
173             goto err;
174     } else if (ppath != NULL) { /* must prepend '/' */
175         size_t buflen = 1 + path_end - path + 1;
176 
177         if ((*ppath = OPENSSL_malloc(buflen)) == NULL)
178             goto err;
179         BIO_snprintf(*ppath, buflen, "/%s", path);
180     }
181     return 1;
182 
183 parse_err:
184     ERR_raise(ERR_LIB_HTTP, HTTP_R_ERROR_PARSING_URL);
185 
186 err:
187     free_pstring(pscheme);
188     free_pstring(puser);
189     free_pstring(phost);
190     free_pstring(pport);
191     free_pstring(ppath);
192     free_pstring(pquery);
193     free_pstring(pfrag);
194     return 0;
195 }
196 
197 #ifndef OPENSSL_NO_HTTP
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         host[sl] = '\0';
271         server = host;
272     }
273 
274     /*
275      * using environment variable names, both lowercase and uppercase variants,
276      * compatible with other HTTP client implementations like wget, curl and git
277      */
278     if (no_proxy == NULL)
279         no_proxy = ossl_safe_getenv("no_proxy");
280     if (no_proxy == NULL)
281         no_proxy = ossl_safe_getenv(OPENSSL_NO_PROXY);
282 
283     if (no_proxy != NULL)
284         found = strstr(no_proxy, server);
285     while (found != NULL
286         && ((found != no_proxy && !ossl_isspace(found[-1]) && found[-1] != ',')
287             || (found[sl] != '\0' && !ossl_isspace(found[sl]) && found[sl] != ',')))
288         found = strstr(found + 1, server);
289     return found == NULL;
290 }
291 
292 /* 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)293 const char *OSSL_HTTP_adapt_proxy(const char *proxy, const char *no_proxy,
294     const char *server, int use_ssl)
295 {
296     /*
297      * using environment variable names, both lowercase and uppercase variants,
298      * compatible with other HTTP client implementations like wget, curl and git
299      */
300     if (proxy == NULL)
301         proxy = ossl_safe_getenv(use_ssl ? "https_proxy" : "http_proxy");
302     if (proxy == NULL)
303         proxy = ossl_safe_getenv(use_ssl ? OPENSSL_HTTPS_PROXY : OPENSSL_HTTP_PROXY);
304 
305     if (proxy == NULL || *proxy == '\0' || !use_proxy(no_proxy, server))
306         return NULL;
307     return proxy;
308 }
309 
310 #endif /* !defined(OPENSSL_NO_HTTP) */
311