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 };
69 
70 extern struct vhost hosts[HOSTSLEN];
71 
72 struct etm {			/* extension to mime */
73 	const char	*mime;
74 	const char	*ext;
75 };
76 
77 struct mime {
78 	struct etm	*t;
79 	size_t		len;
80 	size_t		cap;
81 };
82 
83 struct conf {
84 	int		foreground;
85 	int		port;
86 	int		ipv6;
87 	uint32_t	protos;
88 	struct mime	mime;
89 };
90 
91 extern struct conf conf;
92 extern int exfd;
93 
94 struct iri {
95 	char		*schema;
96 	char		*host;
97 	char		*port;
98 	uint16_t	 port_no;
99 	char		*path;
100 	char		*query;
101 	char		*fragment;
102 };
103 
104 struct parser {
105 	char		*iri;
106 	struct iri	*parsed;
107 	const char	*err;
108 };
109 
110 enum {
111 	S_HANDSHAKE,
112 	S_OPEN,
113 	S_INITIALIZING,
114 	S_SENDING,
115 	S_CLOSING,
116 };
117 
118 struct client {
119 	struct tls	*ctx;
120 	char		 req[GEMINI_URL_LEN];
121 	struct iri	 iri;
122 	int		 state;
123 	int		 code;
124 	const char	*meta;
125 	int		 fd, waiting_on_child;
126 	int		 child;
127 	char		 sbuf[1024];	  /* static buffer */
128 	void		*buf, *i;	  /* mmap buffer */
129 	ssize_t		 len, off;	  /* mmap/static buffer  */
130 	struct sockaddr_storage	 addr;
131 	struct vhost	*host;	/* host she's talking to */
132 };
133 
134 enum {
135 	FILE_EXISTS,
136 	FILE_EXECUTABLE,
137 	FILE_DIRECTORY,
138 	FILE_MISSING,
139 };
140 
141 /* gmid.c */
142 
143 __attribute__((format (printf, 1, 2)))
144 __attribute__((__noreturn__))
145 void fatal(const char*, ...);
146 
147 __attribute__((format (printf, 3, 4)))
148 void logs(int, struct client*, const char*, ...);
149 void log_request(struct client*, char*, size_t);
150 
151 void		 sig_handler(int);
152 int		 starts_with(const char*, const char*);
153 ssize_t		 filesize(int);
154 char		*absolutify_path(const char*);
155 void		 yyerror(const char*);
156 int		 parse_portno(const char*);
157 void		 parse_conf(const char*);
158 void		 load_vhosts(struct tls_config*);
159 int		 make_socket(int, int);
160 int		 listener_main(void);
161 void		 usage(const char*);
162 
163 /* provided by lex/yacc */
164 extern FILE *yyin;
165 extern int yylineno;
166 extern int yyparse(void);
167 extern int yylex(void);
168 
169 /* mime.c */
170 void		 init_mime(struct mime*);
171 void		 add_mime(struct mime*, const char*, const char*);
172 void		 load_default_mime(struct mime*);
173 const char	*mime(struct vhost*, const char*);
174 
175 /* server.c */
176 int		 check_path(struct client*, const char*, int*);
177 int		 open_file(struct pollfd*, struct client*);
178 int		 check_for_cgi(char *, char*, struct pollfd*, struct client*);
179 void		 mark_nonblock(int);
180 void		 handle_handshake(struct pollfd*, struct client*);
181 void		 handle_open_conn(struct pollfd*, struct client*);
182 int		 start_reply(struct pollfd*, struct client*, int, const char*);
183 int		 start_cgi(const char*, const char*, const char*, struct pollfd*, struct client*);
184 void		 send_file(struct pollfd*, struct client*);
185 void		 send_dir(struct pollfd*, struct client*);
186 void		 cgi_poll_on_child(struct pollfd*, struct client*);
187 void		 cgi_poll_on_client(struct pollfd*, struct client*);
188 void		 handle_cgi(struct pollfd*, struct client*);
189 void		 goodbye(struct pollfd*, struct client*);
190 void		 do_accept(int, struct tls*, struct pollfd*, struct client*);
191 void		 handle(struct pollfd*, struct client*);
192 void		 loop(struct tls*, int, int);
193 
194 /* ex.c */
195 int		 send_string(int, const char*);
196 int		 recv_string(int, char**);
197 int		 send_vhost(int, struct vhost*);
198 int		 recv_vhost(int, struct vhost**);
199 int		 send_fd(int, int);
200 int		 recv_fd(int);
201 int		 executor_main(int);
202 
203 /* sandbox.c */
204 void		 sandbox(void);
205 
206 /* utf8.c */
207 int		 valid_multibyte_utf8(struct parser*);
208 
209 /* iri.c */
210 int		 parse_iri(char*, struct iri*, const char**);
211 int		 trim_req_iri(char*);
212 
213 #endif