1 /*
2  * libwebsockets - small server side websockets and web server implementation
3  *
4  * Copyright (C) 2010 - 2019 Andy Green <andy@warmcat.com>
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to
8  * deal in the Software without restriction, including without limitation the
9  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10  * sell copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
22  * IN THE SOFTWARE.
23  */
24 
25 /** \defgroup net Network related helper APIs
26  * ##Network related helper APIs
27  *
28  * These wrap miscellaneous useful network-related functions
29  */
30 ///@{
31 
32 typedef union {
33 #if defined(LWS_WITH_IPV6)
34 	struct sockaddr_in6 sa6;
35 #endif
36 	struct sockaddr_in sa4;
37 } lws_sockaddr46;
38 
39 /**
40  * lws_canonical_hostname() - returns this host's hostname
41  *
42  * This is typically used by client code to fill in the host parameter
43  * when making a client connection.  You can only call it after the context
44  * has been created.
45  *
46  * \param context:	Websocket context
47  */
48 LWS_VISIBLE LWS_EXTERN const char * LWS_WARN_UNUSED_RESULT
49 lws_canonical_hostname(struct lws_context *context);
50 
51 /**
52  * lws_get_peer_addresses() - Get client address information
53  * \param wsi:	Local struct lws associated with
54  * \param fd:		Connection socket descriptor
55  * \param name:	Buffer to take client address name
56  * \param name_len:	Length of client address name buffer
57  * \param rip:	Buffer to take client address IP dotted quad
58  * \param rip_len:	Length of client address IP buffer
59  *
60  *	This function fills in name and rip with the name and IP of
61  *	the client connected with socket descriptor fd.  Names may be
62  *	truncated if there is not enough room.  If either cannot be
63  *	determined, they will be returned as valid zero-length strings.
64  */
65 LWS_VISIBLE LWS_EXTERN void
66 lws_get_peer_addresses(struct lws *wsi, lws_sockfd_type fd, char *name,
67 		       int name_len, char *rip, int rip_len);
68 
69 /**
70  * lws_get_peer_simple() - Get client address information without RDNS
71  *
72  * \param wsi:	Local struct lws associated with
73  * \param name:	Buffer to take client address name
74  * \param namelen:	Length of client address name buffer
75  *
76  * This provides a 123.123.123.123 type IP address in name from the
77  * peer that has connected to wsi
78  */
79 LWS_VISIBLE LWS_EXTERN const char *
80 lws_get_peer_simple(struct lws *wsi, char *name, size_t namelen);
81 
82 LWS_VISIBLE LWS_EXTERN const char *
83 lws_get_peer_simple_fd(lws_sockfd_type fd, char *name, size_t namelen);
84 
85 #define LWS_ITOSA_USABLE	0
86 #define LWS_ITOSA_NOT_EXIST	-1
87 #define LWS_ITOSA_NOT_USABLE	-2
88 #define LWS_ITOSA_BUSY		-3 /* only returned by lws_socket_bind() on
89 					EADDRINUSE */
90 
91 #if !defined(LWS_PLAT_FREERTOS) && !defined(LWS_PLAT_OPTEE)
92 /**
93  * lws_interface_to_sa() - Convert interface name or IP to sockaddr struct
94  *
95  * \param ipv6:		Allow IPV6 addresses
96  * \param ifname:	Interface name or IP
97  * \param addr:		struct sockaddr_in * to be written
98  * \param addrlen:	Length of addr
99  *
100  * This converts a textual network interface name to a sockaddr usable by
101  * other network functions.
102  *
103  * If the network interface doesn't exist, it will return LWS_ITOSA_NOT_EXIST.
104  *
105  * If the network interface is not usable, eg ethernet cable is removed, it
106  * may logically exist but not have any IP address.  As such it will return
107  * LWS_ITOSA_NOT_USABLE.
108  *
109  * If the network interface exists and is usable, it will return
110  * LWS_ITOSA_USABLE.
111  */
112 LWS_VISIBLE LWS_EXTERN int
113 lws_interface_to_sa(int ipv6, const char *ifname, struct sockaddr_in *addr,
114 		    size_t addrlen);
115 #endif
116 
117 /**
118  * lws_sa46_compare_ads() - checks if two sa46 have the same address
119  *
120  * \param sa46a: first
121  * \param sa46b: second
122  *
123  * Returns 0 if the address family and address are the same, otherwise nonzero.
124  */
125 LWS_VISIBLE LWS_EXTERN int
126 lws_sa46_compare_ads(const lws_sockaddr46 *sa46a, const lws_sockaddr46 *sa46b);
127 
128 /*
129  * lws_parse_numeric_address() - converts numeric ipv4 or ipv6 to byte address
130  *
131  * \param ads: the numeric ipv4 or ipv6 address string
132  * \param result: result array
133  * \param max_len: max length of result array
134  *
135  * Converts a 1.2.3.4 or 2001:abcd:123:: or ::ffff:1.2.3.4 formatted numeric
136  * address into an array of network ordered byte address elements.
137  *
138  * Returns < 0 on error, else length of result set, either 4 or 16 for ipv4 /
139  * ipv6.
140  */
141 LWS_VISIBLE LWS_EXTERN int
142 lws_parse_numeric_address(const char *ads, uint8_t *result, size_t max_len);
143 
144 /*
145  * lws_sa46_parse_numeric_address() - converts numeric ipv4 or ipv6 to sa46
146  *
147  * \param ads: the numeric ipv4 or ipv6 address string
148  * \param sa46: pointer to sa46 to set
149  *
150  * Converts a 1.2.3.4 or 2001:abcd:123:: or ::ffff:1.2.3.4 formatted numeric
151  * address into an sa46, a union of sockaddr_in or sockaddr_in6 depending on
152  * what kind of address was found.  sa46->sa4.sin_fmaily will be AF_INET if
153  * ipv4, or AF_INET6 if ipv6.
154  *
155  * Returns 0 if the sa46 was set, else < 0 on error.
156  */
157 LWS_VISIBLE LWS_EXTERN int
158 lws_sa46_parse_numeric_address(const char *ads, lws_sockaddr46 *sa46);
159 
160 /**
161  * lws_write_numeric_address() - convert network byte order ads to text
162  *
163  * \param ads: network byte order address array
164  * \param size: number of bytes valid in ads
165  * \param buf: result buffer to take text format
166  * \param len: max size of text buffer
167  *
168  * Converts an array of network-ordered byte address elements to a textual
169  * representation of the numeric address, like "1.2.3.4" or "::1".  Return 0
170  * if OK else < 0.  ipv6 only supported with LWS_IPV6=1 at cmake.
171  */
172 LWS_VISIBLE LWS_EXTERN int
173 lws_write_numeric_address(const uint8_t *ads, int size, char *buf, size_t len);
174 
175 /**
176  * lws_sa46_write_numeric_address() - convert sa46 ads to textual numeric ads
177  *
178  * \param sa46: the sa46 whose address to show
179  * \param buf: result buffer to take text format
180  * \param len: max size of text buffer
181  *
182  * Converts the ipv4 or ipv6 address in an lws_sockaddr46 to a textual
183  * representation of the numeric address, like "1.2.3.4" or "::1".  Return 0
184  * if OK else < 0.  ipv6 only supported with LWS_IPV6=1 at cmake.
185  */
186 LWS_VISIBLE LWS_EXTERN int
187 lws_sa46_write_numeric_address(lws_sockaddr46 *sa46, char *buf, size_t len);
188 
189 ///@}
190