1 /*
2  * libwebsockets - small server side websockets and web server implementation
3  *
4  * Copyright (C) 2019 - 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  * This is the headers for secure stream api variants that deal with clients in
25  * different threads or even different processes.
26  *
27  * lws_ss_          when client is directly using the event loop
28  * lws_sstc_        when client is in a different thread to the event loop
29  * lws_sspc_        when client is in a different process to the event loop
30  *
31  * The client api is almost the same except the slightly diffent names.
32  */
33 
34 /*
35  * lws_sspc_ apis... different process
36  */
37 
38 /*
39  * Helper translation so user code written to lws_ss_ can be built for
40  * lws_sspc_ in one step by #define LWS_SS_USE_SSPC before including
41  */
42 
43 #if defined(LWS_SS_USE_SSPC)
44 #define lws_ss_handle lws_sspc_handle
45 #define lws_ss_create lws_sspc_create
46 #define lws_ss_destroy lws_sspc_destroy
47 #define lws_ss_request_tx lws_sspc_request_tx
48 #define lws_ss_client_connect lws_sspc_client_connect
49 #define lws_ss_get_sequencer lws_sspc_get_sequencer
50 #define lws_ss_proxy_create lws_sspc_proxy_create
51 #define lws_ss_get_context lws_sspc_get_context
52 #define lws_ss_rideshare lws_sspc_rideshare
53 #define lws_ss_set_metadata lws_sspc_set_metadata
54 #define lws_ss_add_peer_tx_credit lws_sspc_add_peer_tx_credit
55 #define lws_ss_get_est_peer_tx_credit lws_sspc_get_est_peer_tx_credit
56 #endif
57 
58 
59 struct lws_sspc_handle;
60 
61 LWS_VISIBLE LWS_EXTERN int
62 lws_sspc_create(struct lws_context *context, int tsi, const lws_ss_info_t *ssi,
63 	      void *opaque_user_data, struct lws_sspc_handle **ppss,
64 	      struct lws_sequencer *seq_owner, const char **ppayload_fmt);
65 
66 /**
67  * lws_sspc_destroy() - Destroy secure stream
68  *
69  * \param ppss: pointer to lws_ss_t pointer to be destroyed
70  *
71  * Destroys the lws_ss_t pointed to by *ppss, and sets *ppss to NULL.
72  */
73 LWS_VISIBLE LWS_EXTERN void
74 lws_sspc_destroy(struct lws_sspc_handle **ppss);
75 
76 /**
77  * lws_sspc_request_tx() - Schedule stream for tx
78  *
79  * \param pss: pointer to lws_ss_t representing stream that wants to transmit
80  *
81  * Schedules a write on the stream represented by \p pss.  When it's possible to
82  * write on this stream, the *tx callback will occur with an empty buffer for
83  * the stream owner to fill in.
84  */
85 LWS_VISIBLE LWS_EXTERN void
86 lws_sspc_request_tx(struct lws_sspc_handle *pss);
87 
88 /**
89  * lws_sspc_client_connect() - Attempt the client connect
90  *
91  * \param h: secure streams handle
92  *
93  * Starts the connection process for the secure stream.  Returns 0 if OK or
94  * nonzero if we have already failed.
95  */
96 LWS_VISIBLE LWS_EXTERN int
97 lws_sspc_client_connect(struct lws_sspc_handle *h);
98 
99 /**
100  * lws_sspc_get_sequencer() - Return parent sequencer pointer if any
101  *
102  * \param h: secure streams handle
103  *
104  * Returns NULL if the secure stream is not associated with a sequencer.
105  * Otherwise returns a pointer to the owning sequencer.  You can use this to
106  * identify which sequencer to direct messages to, from the secure stream
107  * callback.
108  */
109 LWS_VISIBLE LWS_EXTERN struct lws_sequencer *
110 lws_sspc_get_sequencer(struct lws_sspc_handle *h);
111 
112 /**
113  * lws_sspc_proxy_create() - Start a unix domain socket proxy for Secure Streams
114  *
115  * \param context: lws_context
116  *
117  * Creates a vhost that listens on an abstract namespace unix domain socket at
118  * address "proxy.ss.lws".  Client connections to this proxy to Secure Streams
119  */
120 LWS_VISIBLE LWS_EXTERN int
121 lws_sspc_proxy_create(struct lws_context *context);
122 
123 /**
124  * lws_ss_get_context() - convenience helper to recover the lws context
125  *
126  * \h: secure streams handle
127  *
128  * Returns the lws context.  Dispenses with the need to pass a copy of it into
129  * your secure streams handler.
130  */
131 
132 LWS_VISIBLE LWS_EXTERN struct lws_context *
133 lws_sspc_get_context(struct lws_sspc_handle *h);
134 
135 LWS_VISIBLE LWS_EXTERN const struct lws_protocols lws_sspc_protocols[];
136 
137 LWS_VISIBLE LWS_EXTERN const char *
138 lws_sspc_rideshare(struct lws_sspc_handle *h);
139 
140 
141 /**
142  * lws_sspc_set_metadata() - allow user to bind external data to defined ss metadata
143  *
144  * \h: secure streams handle
145  * \name: metadata name from the policy
146  * \value: pointer to user-managed data to bind to name
147  * \len: length of the user-managed data in value
148  *
149  * Binds user-managed data to the named metadata item from the ss policy.
150  * If present, the metadata item is handled in a protocol-specific way using
151  * the associated policy information.  For example, in the policy
152  *
153  *  	"\"metadata\":"		"["
154  *		"{\"uptag\":"  "\"X-Upload-Tag:\"},"
155  *		"{\"ctype\":"  "\"Content-Type:\"},"
156  *		"{\"xctype\":" "\"X-Content-Type:\"}"
157  *	"],"
158  *
159  * when the policy is using h1 is interpreted to add h1 headers of the given
160  * name with the value of the metadata on the left.
161  *
162  * Return 0 if OK.
163  */
164 LWS_VISIBLE LWS_EXTERN int
165 lws_sspc_set_metadata(struct lws_sspc_handle *h, const char *name,
166 		      void *value, size_t len);
167 
168 LWS_VISIBLE LWS_EXTERN int
169 lws_sspc_add_peer_tx_credit(struct lws_sspc_handle *h, int32_t add);
170 
171 LWS_VISIBLE LWS_EXTERN int
172 lws_sspc_get_est_peer_tx_credit(struct lws_sspc_handle *h);
173