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 #ifndef INFTIM
32 # define INFTIM -1
33 #endif
34 
35 #define GEMINI_URL_LEN (1024+3)	/* URL max len + \r\n + \0 */
36 
37 /* large enough to hold a copy of a gemini URL and still have extra room */
38 #define PATHBUF		2048
39 
40 #define SUCCESS		20
41 #define TEMP_FAILURE	40
42 #define NOT_FOUND	51
43 #define PROXY_REFUSED	53
44 #define BAD_REQUEST	59
45 
46 #define MAX_USERS	64
47 
48 #define HOSTSLEN	64
49 
50 #define LOGE(c, fmt, ...) logs(LOG_ERR,     c, fmt, __VA_ARGS__)
51 #define LOGW(c, fmt, ...) logs(LOG_WARNING, c, fmt, __VA_ARGS__)
52 #define LOGN(c, fmt, ...) logs(LOG_NOTICE,  c, fmt, __VA_ARGS__)
53 #define LOGI(c, fmt, ...) logs(LOG_INFO,    c, fmt, __VA_ARGS__)
54 #define LOGD(c, fmt, ...) logs(LOG_DEBUG,   c, fmt, __VA_ARGS__)
55 
56 struct vhost {
57 	const char	*domain;
58 	const char	*cert;
59 	const char	*key;
60 	const char	*dir;
61 	const char	*cgi;
62 	char		*lang;
63 	int		 dirfd;
64 	char		*default_mime;
65 };
66 
67 extern struct vhost hosts[HOSTSLEN];
68 
69 struct etm {			/* extension to mime */
70 	const char	*mime;
71 	const char	*ext;
72 };
73 
74 struct mimes {
75 	struct etm	*t;
76 	size_t		len;
77 	size_t		cap;
78 };
79 
80 struct conf {
81 	int		foreground;
82 	int		port;
83 	int		ipv6;
84 	uint32_t	protos;
85 	struct mimes	mimes;
86 };
87 
88 extern struct conf conf;
89 extern int exfd;
90 
91 enum {
92 	S_HANDSHAKE,
93 	S_OPEN,
94 	S_INITIALIZING,
95 	S_SENDING,
96 	S_CLOSING,
97 };
98 
99 struct client {
100 	struct tls	*ctx;
101 	int		 state;
102 	int		 code;
103 	const char	*meta;
104 	int		 fd, waiting_on_child;
105 	int		 child;
106 	char		 sbuf[1024];	  /* static buffer */
107 	void		*buf, *i;	  /* mmap buffer */
108 	ssize_t		 len, off;	  /* mmap/static buffer  */
109 	int		 af;
110 	struct sockaddr_storage	 addr;
111 	struct vhost	*host;	/* host she's talking to */
112 };
113 
114 struct iri {
115 	char		*schema;
116 	char		*host;
117 	char		*port;
118 	uint16_t	 port_no;
119 	char		*path;
120 	char		*query;
121 	char		*fragment;
122 };
123 
124 struct parser {
125 	char		*iri;
126 	struct iri	*parsed;
127 	const char	*err;
128 };
129 
130 enum {
131 	FILE_EXISTS,
132 	FILE_EXECUTABLE,
133 	FILE_DIRECTORY,
134 	FILE_MISSING,
135 };
136 
137 /* gmid.c */
138 
139 __attribute__((format (printf, 1, 2)))
140 __attribute__((__noreturn__))
141 void fatal(const char*, ...);
142 
143 __attribute__((format (printf, 3, 4)))
144 void logs(int, struct client*, const char*, ...);
145 
146 void		 sig_handler(int);
147 int		 starts_with(const char*, const char*);
148 ssize_t		 filesize(int);
149 char		*absolutify_path(const char*);
150 void		 yyerror(const char*);
151 int		 parse_portno(const char*);
152 void		 parse_conf(const char*);
153 void		 load_vhosts(struct tls_config*);
154 int		 make_soket(int);
155 int		 listener_main();
156 void		 usage(const char*);
157 
158 /* provided by lex/yacc */
159 extern FILE *yyin;
160 extern int yylineno;
161 extern int yyparse(void);
162 extern int yylex(void);
163 
164 /* mime.c */
165 void		 init_mime(void);
166 void		 add_mime(const char*, const char*);
167 void		 load_default_mime(void);
168 int		 load_mime_file(const char*);
169 const char	*mime(struct vhost*, const char*);
170 
171 /* server.c */
172 int		 check_path(struct client*, const char*, int*);
173 int		 open_file(char*, char*, struct pollfd*, struct client*);
174 int		 check_for_cgi(char *, char*, struct pollfd*, struct client*);
175 void		 mark_nonblock(int);
176 void		 handle_handshake(struct pollfd*, struct client*);
177 void		 handle_open_conn(struct pollfd*, struct client*);
178 int		 start_reply(struct pollfd*, struct client*, int, const char*);
179 int		 start_cgi(const char*, const char*, const char*, struct pollfd*, struct client*);
180 void		 send_file(char*, char*, struct pollfd*, struct client*);
181 void		 send_dir(char*, struct pollfd*, struct client*);
182 void		 cgi_poll_on_child(struct pollfd*, struct client*);
183 void		 cgi_poll_on_client(struct pollfd*, struct client*);
184 void		 handle_cgi(struct pollfd*, struct client*);
185 void		 goodbye(struct pollfd*, struct client*);
186 void		 do_accept(int, struct tls*, struct pollfd*, struct client*);
187 void		 handle(struct pollfd*, struct client*);
188 void		 loop(struct tls*, int, int);
189 
190 /* ex.c */
191 int		 send_string(int, const char*);
192 int		 recv_string(int, char**);
193 int		 send_vhost(int, struct vhost*);
194 int		 recv_vhost(int, struct vhost**);
195 int		 send_fd(int, int);
196 int		 recv_fd(int);
197 int		 executor_main(int);
198 
199 /* sandbox.c */
200 void		 sandbox();
201 
202 /* utf8.c */
203 int		 valid_multibyte_utf8(struct parser*);
204 
205 /* iri.c */
206 int		 parse_iri(char*, struct iri*, const char**);
207 int		 trim_req_iri(char*);
208 
209 #endif