1/*
2 * libwebsockets - small server side websockets and web server implementation
3 *
4 * Copyright (C) 2010 - 2020 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#if defined(LWS_ESP_PLATFORM)
33#include <lwip/sockets.h>
34#endif
35
36/* cope with large amounts of route information */
37typedef uint16_t lws_route_uidx_t;
38
39typedef struct lws_dns_score {
40	uint8_t precedence;
41	uint8_t label;
42} lws_dns_score_t;
43
44/*
45 * This represents an entry in the system routing table
46 */
47
48typedef struct lws_route {
49	lws_dll2_t		list;
50
51	lws_sockaddr46		src;
52	lws_sockaddr46		dest;
53	lws_sockaddr46		gateway;
54
55	struct lws_route	*source; /* when used as lws_dns_sort_t */
56	lws_dns_score_t		score; /* when used as lws_dns_sort_t */
57
58	int			if_idx;
59	int			priority;
60	int			ifa_flags; /* if source_ads */
61
62	lws_route_uidx_t	uidx; /* unique index for this route */
63
64	uint8_t			proto;
65	uint8_t			dest_len;
66	uint8_t			src_len;
67	uint8_t			scope; /* if source_ads */
68	uint8_t			af; /* if source_ads */
69
70	uint8_t			source_ads:1;
71} lws_route_t;
72
73/*
74 * We reuse the route object as the dns sort granule, so there's only one
75 * struct needs to know all the gnarly ipv6 details
76 */
77
78typedef lws_route_t lws_dns_sort_t;
79
80/**
81 * lws_canonical_hostname() - returns this host's hostname
82 *
83 * This is typically used by client code to fill in the host parameter
84 * when making a client connection.  You can only call it after the context
85 * has been created.
86 *
87 * \param context:	Websocket context
88 */
89LWS_VISIBLE LWS_EXTERN const char * LWS_WARN_UNUSED_RESULT
90lws_canonical_hostname(struct lws_context *context);
91
92/**
93 * lws_get_peer_addresses() - Get client address information
94 * \param wsi:	Local struct lws associated with
95 * \param fd:		Connection socket descriptor
96 * \param name:	Buffer to take client address name
97 * \param name_len:	Length of client address name buffer
98 * \param rip:	Buffer to take client address IP dotted quad
99 * \param rip_len:	Length of client address IP buffer
100 *
101 *	This function fills in name and rip with the name and IP of
102 *	the client connected with socket descriptor fd.  Names may be
103 *	truncated if there is not enough room.  If either cannot be
104 *	determined, they will be returned as valid zero-length strings.
105 */
106LWS_VISIBLE LWS_EXTERN void
107lws_get_peer_addresses(struct lws *wsi, lws_sockfd_type fd, char *name,
108		       int name_len, char *rip, int rip_len);
109
110/**
111 * lws_get_peer_simple() - Get client address information without RDNS
112 *
113 * \param wsi:	Local struct lws associated with
114 * \param name:	Buffer to take client address name
115 * \param namelen:	Length of client address name buffer
116 *
117 * This provides a 123.123.123.123 type IP address in name from the
118 * peer that has connected to wsi
119 */
120LWS_VISIBLE LWS_EXTERN const char *
121lws_get_peer_simple(struct lws *wsi, char *name, size_t namelen);
122
123LWS_VISIBLE LWS_EXTERN const char *
124lws_get_peer_simple_fd(lws_sockfd_type fd, char *name, size_t namelen);
125
126#define LWS_ITOSA_USABLE	0
127#define LWS_ITOSA_NOT_EXIST	-1
128#define LWS_ITOSA_NOT_USABLE	-2
129#define LWS_ITOSA_BUSY		-3 /* only returned by lws_socket_bind() on
130					EADDRINUSE */
131
132#if !defined(LWS_PLAT_FREERTOS) && !defined(LWS_PLAT_OPTEE)
133/**
134 * lws_interface_to_sa() - Convert interface name or IP to sockaddr struct
135 *
136 * \param ipv6:		Allow IPV6 addresses
137 * \param ifname:	Interface name or IP
138 * \param addr:		struct sockaddr_in * to be written
139 * \param addrlen:	Length of addr
140 *
141 * This converts a textual network interface name to a sockaddr usable by
142 * other network functions.
143 *
144 * If the network interface doesn't exist, it will return LWS_ITOSA_NOT_EXIST.
145 *
146 * If the network interface is not usable, eg ethernet cable is removed, it
147 * may logically exist but not have any IP address.  As such it will return
148 * LWS_ITOSA_NOT_USABLE.
149 *
150 * If the network interface exists and is usable, it will return
151 * LWS_ITOSA_USABLE.
152 */
153LWS_VISIBLE LWS_EXTERN int
154lws_interface_to_sa(int ipv6, const char *ifname, struct sockaddr_in *addr,
155		    size_t addrlen);
156#endif
157
158/**
159 * lws_sa46_compare_ads() - checks if two sa46 have the same address
160 *
161 * \param sa46a: first
162 * \param sa46b: second
163 *
164 * Returns 0 if the address family is INET or INET6 and the address is the same,
165 * or if the AF is the same but not INET or INET6, otherwise nonzero.
166 */
167LWS_VISIBLE LWS_EXTERN int
168lws_sa46_compare_ads(const lws_sockaddr46 *sa46a, const lws_sockaddr46 *sa46b);
169
170/**
171 * lws_sa46_on_net() - checks if an sa46 is on the subnet represented by another
172 *
173 * \param sa46a: first
174 * \param sa46_net: network
175 * \param net_len: length of network non-mask
176 *
177 * Returns 0 if sa46a belongs on network sa46_net/net_len
178 *
179 * If there is an ipv4 / v6 mismatch between the ip and the net, the ipv4
180 * address is promoted to ::ffff:x.x.x.x before the comparison.
181 */
182LWS_VISIBLE LWS_EXTERN int
183lws_sa46_on_net(const lws_sockaddr46 *sa46a, const lws_sockaddr46 *sa46_net,
184			int net_len);
185
186/*
187 * lws_parse_numeric_address() - converts numeric ipv4 or ipv6 to byte address
188 *
189 * \param ads: the numeric ipv4 or ipv6 address string
190 * \param result: result array
191 * \param max_len: max length of result array
192 *
193 * Converts a 1.2.3.4 or 2001:abcd:123:: or ::ffff:1.2.3.4 formatted numeric
194 * address into an array of network ordered byte address elements.
195 *
196 * Returns < 0 on error, else length of result set, either 4 or 16 for ipv4 /
197 * ipv6.
198 */
199LWS_VISIBLE LWS_EXTERN int
200lws_parse_numeric_address(const char *ads, uint8_t *result, size_t max_len);
201
202/*
203 * lws_sa46_parse_numeric_address() - converts numeric ipv4 or ipv6 to sa46
204 *
205 * \param ads: the numeric ipv4 or ipv6 address string
206 * \param sa46: pointer to sa46 to set
207 *
208 * Converts a 1.2.3.4 or 2001:abcd:123:: or ::ffff:1.2.3.4 formatted numeric
209 * address into an sa46, a union of sockaddr_in or sockaddr_in6 depending on
210 * what kind of address was found.  sa46->sa4.sin_fmaily will be AF_INET if
211 * ipv4, or AF_INET6 if ipv6.
212 *
213 * Returns 0 if the sa46 was set, else < 0 on error.
214 */
215LWS_VISIBLE LWS_EXTERN int
216lws_sa46_parse_numeric_address(const char *ads, lws_sockaddr46 *sa46);
217
218/**
219 * lws_write_numeric_address() - convert network byte order ads to text
220 *
221 * \param ads: network byte order address array
222 * \param size: number of bytes valid in ads
223 * \param buf: result buffer to take text format
224 * \param len: max size of text buffer
225 *
226 * Converts an array of network-ordered byte address elements to a textual
227 * representation of the numeric address, like "1.2.3.4" or "::1".  Returns the
228 * number of chars written into buf, else < 0.  ipv6 only supported with
229 * LWS_IPV6=1 at cmake.
230 */
231LWS_VISIBLE LWS_EXTERN int
232lws_write_numeric_address(const uint8_t *ads, int size, char *buf, size_t len);
233
234/**
235 * lws_sa46_write_numeric_address() - convert sa46 ads to textual numeric ads
236 *
237 * \param sa46: the sa46 whose address to show
238 * \param buf: result buffer to take text format
239 * \param len: max size of text buffer
240 *
241 * Converts the ipv4 or ipv6 address in an lws_sockaddr46 to a textual
242 * representation of the numeric address, like "1.2.3.4" or "::1".  Returns the
243 * number of chars written into buf, else < 0.  ipv6 only supported with
244 * LWS_IPV6=1 at cmake.
245 */
246LWS_VISIBLE LWS_EXTERN int
247lws_sa46_write_numeric_address(lws_sockaddr46 *sa46, char *buf, size_t len);
248
249///@}
250