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 	int		 dirfd;
63 };
64 
65 extern struct vhost hosts[HOSTSLEN];
66 
67 struct conf {
68 	int	foreground;
69 	int	port;
70 	int	ipv6;
71 	uint32_t protos;
72 };
73 
74 extern struct conf conf;
75 
76 enum {
77 	S_HANDSHAKE,
78 	S_OPEN,
79 	S_INITIALIZING,
80 	S_SENDING,
81 	S_CLOSING,
82 };
83 
84 struct client {
85 	struct tls	*ctx;
86 	int		 state;
87 	int		 code;
88 	const char	*meta;
89 	int		 fd, waiting_on_child;
90 	pid_t		 child;
91 	char		 sbuf[1024];	  /* static buffer */
92 	void		*buf, *i;	  /* mmap buffer */
93 	ssize_t		 len, off;	  /* mmap/static buffer  */
94 	int		 af;
95 	struct sockaddr_storage	 addr;
96 	struct vhost	*host;	/* host she's talking to */
97 };
98 
99 struct iri {
100 	char		*schema;
101 	char		*host;
102 	char		*port;
103 	uint16_t	 port_no;
104 	char		*path;
105 	char		*query;
106 	char		*fragment;
107 };
108 
109 struct parser {
110 	char		*iri;
111 	struct iri	*parsed;
112 	const char	*err;
113 };
114 
115 enum {
116 	FILE_EXISTS,
117 	FILE_EXECUTABLE,
118 	FILE_DIRECTORY,
119 	FILE_MISSING,
120 };
121 
122 /* gmid.c */
123 __attribute__ ((format (printf, 3, 4))) void logs(int, struct client*, const char*, ...);
124 
125 void		 sig_handler(int);
126 int		 starts_with(const char*, const char*);
127 
128 int		 start_reply(struct pollfd*, struct client*, int, const char*);
129 ssize_t		 filesize(int);
130 const char	*path_ext(const char*);
131 const char	*mime(const char*);
132 int		 check_path(struct client*, const char*, int*);
133 int		 open_file(char*, char*, struct pollfd*, struct client*);
134 void		 send_file(char*, char*, struct pollfd*, struct client*);
135 void		 send_dir(char*, struct pollfd*, struct client*);
136 void		 handle_handshake(struct pollfd*, struct client*);
137 void		 handle_open_conn(struct pollfd*, struct client*);
138 void		 handle(struct pollfd*, struct client*);
139 
140 void		 mark_nonblock(int);
141 int		 make_soket(int);
142 void		 do_accept(int, struct tls*, struct pollfd*, struct client*);
143 void		 goodbye(struct pollfd*, struct client*);
144 void		 loop(struct tls*, int, int);
145 
146 char		*absolutify_path(const char*);
147 void		 yyerror(const char*);
148 int		 parse_portno(const char*);
149 void		 parse_conf(const char*);
150 void		 load_vhosts(struct tls_config*);
151 
152 void		 usage(const char*);
153 
154 /* provided by lex/yacc */
155 extern FILE *yyin;
156 extern int yylineno;
157 extern int yyparse(void);
158 extern int yylex(void);
159 
160 /* cgi.c */
161 int		 check_for_cgi(char *, char*, struct pollfd*, struct client*);
162 int		 start_cgi(const char*, const char*, const char*, struct pollfd*, struct client*);
163 void		 cgi_poll_on_child(struct pollfd*, struct client*);
164 void		 cgi_poll_on_client(struct pollfd*, struct client*);
165 void		 handle_cgi(struct pollfd*, struct client*);
166 
167 /* sandbox.c */
168 void		 sandbox();
169 
170 /* utf8.c */
171 int		 valid_multibyte_utf8(struct parser*);
172 
173 /* iri.c */
174 int		 parse_iri(char*, struct iri*, const char**);
175 int		 trim_req_iri(char*);
176 
177 #endif