1 /*
2  * Copyright (c) 2020 Omar Polo <op@omarpolo.com>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #ifndef GMID_H
18 #define GMID_H
19 
20 #include <arpa/inet.h>
21 #include <netinet/in.h>
22 #include <sys/socket.h>
23 
24 #include <poll.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <syslog.h>
28 #include <tls.h>
29 #include <unistd.h>
30 
31 #include "config.h"
32 
33 #ifndef INFTIM
34 # define INFTIM -1
35 #endif
36 
37 #define GEMINI_URL_LEN (1024+3)	/* URL max len + \r\n + \0 */
38 
39 /* large enough to hold a copy of a gemini URL and still have extra room */
40 #define PATHBUF		2048
41 
42 #define SUCCESS		20
43 #define TEMP_REDIRECT	30
44 #define TEMP_FAILURE	40
45 #define NOT_FOUND	51
46 #define PROXY_REFUSED	53
47 #define BAD_REQUEST	59
48 
49 #define MAX_USERS	64
50 
51 #define HOSTSLEN	64
52 
53 #define LOGE(c, fmt, ...) logs(LOG_ERR,     c, fmt, __VA_ARGS__)
54 #define LOGW(c, fmt, ...) logs(LOG_WARNING, c, fmt, __VA_ARGS__)
55 #define LOGN(c, fmt, ...) logs(LOG_NOTICE,  c, fmt, __VA_ARGS__)
56 #define LOGI(c, fmt, ...) logs(LOG_INFO,    c, fmt, __VA_ARGS__)
57 #define LOGD(c, fmt, ...) logs(LOG_DEBUG,   c, fmt, __VA_ARGS__)
58 
59 struct vhost {
60 	const char	*domain;
61 	const char	*cert;
62 	const char	*key;
63 	const char	*dir;
64 	const char	*cgi;
65 	char		*lang;
66 	int		 dirfd;
67 	char		*default_mime;
68 	char		*index;
69 };
70 
71 extern struct vhost hosts[HOSTSLEN];
72 
73 struct etm {			/* extension to mime */
74 	const char	*mime;
75 	const char	*ext;
76 };
77 
78 struct mime {
79 	struct etm	*t;
80 	size_t		len;
81 	size_t		cap;
82 };
83 
84 struct conf {
85 	int		foreground;
86 	int		port;
87 	int		ipv6;
88 	uint32_t	protos;
89 	struct mime	mime;
90 };
91 
92 extern struct conf conf;
93 extern int exfd;
94 
95 struct iri {
96 	char		*schema;
97 	char		*host;
98 	char		*port;
99 	uint16_t	 port_no;
100 	char		*path;
101 	char		*query;
102 	char		*fragment;
103 };
104 
105 struct parser {
106 	char		*iri;
107 	struct iri	*parsed;
108 	const char	*err;
109 };
110 
111 enum {
112 	S_HANDSHAKE,
113 	S_OPEN,
114 	S_INITIALIZING,
115 	S_SENDING,
116 	S_CLOSING,
117 };
118 
119 struct client {
120 	struct tls	*ctx;
121 	char		 req[GEMINI_URL_LEN];
122 	struct iri	 iri;
123 	int		 state;
124 	int		 code;
125 	const char	*meta;
126 	int		 fd, waiting_on_child;
127 	int		 child;
128 	char		 sbuf[1024];	  /* static buffer */
129 	void		*buf, *i;	  /* mmap buffer */
130 	ssize_t		 len, off;	  /* mmap/static buffer  */
131 	struct sockaddr_storage	 addr;
132 	struct vhost	*host;	/* host she's talking to */
133 };
134 
135 enum {
136 	FILE_EXISTS,
137 	FILE_EXECUTABLE,
138 	FILE_DIRECTORY,
139 	FILE_MISSING,
140 };
141 
142 /* gmid.c */
143 
144 __attribute__((format (printf, 1, 2)))
145 __attribute__((__noreturn__))
146 void fatal(const char*, ...);
147 
148 __attribute__((format (printf, 3, 4)))
149 void logs(int, struct client*, const char*, ...);
150 void log_request(struct client*, char*, size_t);
151 
152 void		 sig_handler(int);
153 int		 starts_with(const char*, const char*);
154 int		 ends_with(const char*, const char*);
155 ssize_t		 filesize(int);
156 char		*absolutify_path(const char*);
157 void		 yyerror(const char*);
158 int		 parse_portno(const char*);
159 void		 parse_conf(const char*);
160 void		 load_vhosts(struct tls_config*);
161 int		 make_socket(int, int);
162 int		 listener_main(void);
163 void		 usage(const char*);
164 
165 /* provided by lex/yacc */
166 extern FILE *yyin;
167 extern int yylineno;
168 extern int yyparse(void);
169 extern int yylex(void);
170 
171 /* mime.c */
172 void		 init_mime(struct mime*);
173 void		 add_mime(struct mime*, const char*, const char*);
174 void		 load_default_mime(struct mime*);
175 const char	*mime(struct vhost*, const char*);
176 
177 /* server.c */
178 int		 check_path(struct client*, const char*, int*);
179 int		 open_file(struct pollfd*, struct client*);
180 int		 check_for_cgi(char *, char*, struct pollfd*, struct client*);
181 void		 mark_nonblock(int);
182 void		 handle_handshake(struct pollfd*, struct client*);
183 void		 handle_open_conn(struct pollfd*, struct client*);
184 int		 start_reply(struct pollfd*, struct client*, int, const char*);
185 int		 start_cgi(const char*, const char*, const char*, struct pollfd*, struct client*);
186 void		 send_file(struct pollfd*, struct client*);
187 void		 send_dir(struct pollfd*, struct client*);
188 void		 cgi_poll_on_child(struct pollfd*, struct client*);
189 void		 cgi_poll_on_client(struct pollfd*, struct client*);
190 void		 handle_cgi(struct pollfd*, struct client*);
191 void		 close_conn(struct pollfd*, struct client*);
192 void		 goodbye(struct pollfd*, struct client*, int, const char*);
193 void		 do_accept(int, struct tls*, struct pollfd*, struct client*);
194 void		 handle(struct pollfd*, struct client*);
195 void		 loop(struct tls*, int, int);
196 
197 /* ex.c */
198 int		 send_string(int, const char*);
199 int		 recv_string(int, char**);
200 int		 send_vhost(int, struct vhost*);
201 int		 recv_vhost(int, struct vhost**);
202 int		 send_fd(int, int);
203 int		 recv_fd(int);
204 int		 executor_main(int);
205 
206 /* sandbox.c */
207 void		 sandbox(void);
208 
209 /* utf8.c */
210 int		 valid_multibyte_utf8(struct parser*);
211 
212 /* iri.c */
213 int		 parse_iri(char*, struct iri*, const char**);
214 int		 trim_req_iri(char*);
215 
216 #endif