1 /*	$Id: irc.c,v 1.2 2015/08/20 17:29:16 dhartmei Exp $ */
2 
3 /*
4  * Copyright (c) 2023 Omar Polo <op@openbsd.org>
5  * Copyright (c) 2003-2004 Daniel Hartmeier
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  *    - Redistributions of source code must retain the above copyright
13  *      notice, this list of conditions and the following disclaimer.
14  *    - Redistributions in binary form must reproduce the above
15  *      copyright notice, this list of conditions and the following
16  *      disclaimer in the documentation and/or other materials provided
17  *      with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
22  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
23  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
25  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
26  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
27  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
29  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  *
32  */
33 
34 #include <err.h>
35 #include <stdarg.h>
36 #include <stdio.h>
37 #include <string.h>
38 
39 #include "irc.h"
40 #include "icb.h"
41 
42 extern void	 scan(const char **, char *, size_t, const char *,
43 		    const char *);
44 extern void	 icbirc_quit(void);
45 extern int	 sync_write(int, const char *, int);
46 
47 static void	 irc_cmd(char *, int, int);
48 
49 static void	 irc_send_pong(int, const char *);
50 
51 char irc_pass[256];
52 char irc_ident[256];
53 char irc_nick[256];
54 char irc_channel[256];
55 int in_irc_channel;
56 
57 /*
58  * irc_recv() receives read(2) chunks and assembles complete lines, which are
59  * passed to irc_cmd(). Overlong lines are truncated after 65kB.
60  *
61  * XXX: argument checking is not as strong as for ICB (trusting the client)
62  *
63  */
64 
65 void
66 irc_recv(const char *buf, unsigned len, int client_fd, int server_fd)
67 {
68 	static char cmd[65535];
69 	static unsigned off = 0;
70 
71 	while (len > 0) {
72 		while (len > 0 && off < (sizeof(cmd) - 1) && *buf != '\n') {
73 			cmd[off++] = *buf++;
74 			len--;
75 		}
76 		if (off == (sizeof(cmd) - 1))
77 			while (len > 0 && *buf != '\n') {
78 				buf++;
79 				len--;
80 			}
81 		/* off <= sizeof(cmd) - 1 */
82 		if (len > 0 && *buf == '\n') {
83 			buf++;
84 			len--;
85 			if (off > 0 && cmd[off - 1] == '\r')
86 				cmd[off - 1] = 0;
87 			else
88 				cmd[off] = 0;
89 			irc_cmd(cmd, client_fd, server_fd);
90 			off = 0;
91 		}
92 	}
93 }
94 
95 static void
96 irc_cmd(char *cmd, int client_fd, int server_fd)
97 {
98 	if (!strncasecmp(cmd, "RAWICB ", 7)) {
99 		icb_send_raw(server_fd, cmd + 7);
100 		return;
101 	}
102 
103 	char *argv[10], *p;
104 	int argc = 1;
105 
106 	for (p = cmd, argv[0] = p; argc < 10 && (p = strchr(p, ' ')) != NULL;
107 	    argc++) {
108 		*p = 0;
109 		p++;
110 		while (*p == ' ')
111 			p++;
112 		if (*p == ':') {
113 			argv[argc] = p + 1;
114 			argc++;
115 			break;
116 		}
117 		argv[argc] = p;
118 	}
119 
120 	if (!strcasecmp(argv[0], "PASS")) {
121 		strlcpy(irc_pass, argv[1], sizeof(irc_pass));
122 	} else if (!strcasecmp(argv[0], "USER")) {
123 		strlcpy(irc_ident, argv[1], sizeof(irc_ident));
124 		if (!icb_logged_in && irc_nick[0] && irc_ident[0])
125 			icb_send_login(server_fd, irc_nick,
126 			    irc_ident, irc_pass);
127 	} else if (!strcasecmp(argv[0], "NICK")) {
128 		strlcpy(irc_nick, argv[1], sizeof(irc_nick));
129 		if (icb_logged_in)
130 			icb_send_name(server_fd, irc_nick);
131 		else if (irc_nick[0] && irc_ident[0])
132 			icb_send_login(server_fd, irc_nick,
133 			    irc_ident, irc_pass);
134 	} else if (!strcasecmp(argv[0], "JOIN")) {
135 		icb_send_group(server_fd,
136 		    argv[1] + (argv[1][0] == '#' ? 1 : 0));
137 	} else if (!strcasecmp(argv[0], "PART")) {
138 		in_irc_channel = 0;
139 	} else if (!strcasecmp(argv[0], "PRIVMSG") ||
140 	    !strcasecmp(argv[0], "NOTICE")) {
141 		char msg[8192];
142 		unsigned i, j;
143 
144 		strlcpy(msg, argv[2], sizeof(msg));
145 		/* strip \001 found in CTCP messages */
146 		i = 0;
147 		while (msg[i]) {
148 			if (msg[i] == '\001') {
149 				for (j = i; msg[j + 1]; ++j)
150 					msg[j] = msg[j + 1];
151 				msg[j] = 0;
152 			} else
153 				i++;
154 		}
155 		if (!strcmp(argv[1], irc_channel))
156 			icb_send_openmsg(server_fd, msg);
157 		else
158 			icb_send_privmsg(server_fd, argv[1], msg);
159 	} else if (!strcasecmp(argv[0], "MODE")) {
160 		if (strcmp(argv[1], irc_channel))
161 			return;
162 		if (argc == 2)
163 			icb_send_names(server_fd, irc_channel);
164 		else {
165 			if (strcmp(argv[2], "+o")) {
166 				warnx("irc_cmd: invalid MODE args '%s'",
167 				    argv[2]);
168 				return;
169 			}
170 			icb_send_pass(server_fd, argv[3]);
171 		}
172 	} else if (!strcasecmp(argv[0], "TOPIC")) {
173 		if (strcmp(argv[1], irc_channel)) {
174 			warnx("irc_cmd: invalid TOPIC channel '%s'",
175 			    argv[1]);
176 			return;
177 		}
178 		icb_send_topic(server_fd, argv[2]);
179 	} else if (!strcasecmp(argv[0], "LIST")) {
180 		icb_send_list(server_fd);
181 	} else if (!strcasecmp(argv[0], "NAMES")) {
182 		icb_send_names(server_fd, argv[1]);
183 	} else if (!strcasecmp(argv[0], "WHOIS")) {
184 		icb_send_whois(server_fd, argv[1]);
185 	} else if (!strcasecmp(argv[0], "WHO")) {
186 		icb_send_who(server_fd, argv[1]);
187 	} else if (!strcasecmp(argv[0], "KICK")) {
188 		if (strcmp(argv[1], irc_channel)) {
189 			warnx("irc_cmd: invalid KICK args '%s'", argv[1]);
190 			return;
191 		}
192 		icb_send_boot(server_fd, argv[2]);
193 	} else if (!strcasecmp(argv[0], "PING")) {
194 		icb_send_noop(server_fd);
195 		irc_send_pong(client_fd, argv[1]);
196 	} else if (!strcasecmp(argv[0], "QUIT")) {
197 		warnx("client QUIT");
198 		icbirc_quit();
199 	} else if (!strcasecmp(argv[0], "CAP")) {
200 		if (!strcasecmp(argv[1], "LS")) {
201 			printf("CAP * LS\n");
202 			fflush(stdout);
203 		} else if (!strcasecmp(argv[1], "REQ")) {
204 			printf("CAP * NAK :%s\n", argv[2]);
205 			fflush(stdout);
206 		} else if (!strcasecmp(argv[1], "END"))
207 			;
208 		else
209 			warnx("irc_cmd: unknown command 'CAP %s'", argv[1]);
210 	} else
211 		warnx("irc_cmd: unknown command '%s'", argv[0]);
212 }
213 
214 void
215 irc_send_notice(int fd, const char *format, ...)
216 {
217 	char cmd[8192], msg[8192];
218 	va_list ap;
219 
220 	va_start(ap, format);
221 	vsnprintf(msg, sizeof(msg), format, ap);
222 	va_end(ap);
223 	snprintf(cmd, sizeof(cmd), "NOTICE %s\r\n", msg);
224 	sync_write(fd, cmd, strlen(cmd));
225 }
226 
227 void
228 irc_send_code(int fd, const char *from, const char *nick, const char *code,
229     const char *format, ...)
230 {
231 	char cmd[8192], msg[8192];
232 	va_list ap;
233 
234 	va_start(ap, format);
235 	vsnprintf(msg, sizeof(msg), format, ap);
236 	va_end(ap);
237 	snprintf(cmd, sizeof(cmd), ":%s %s %s :%s\r\n", from, code, nick, msg);
238 	sync_write(fd, cmd, strlen(cmd));
239 }
240 
241 void
242 irc_send_msg(int fd, const char *src, const char *dst, const char *msg)
243 {
244 	char cmd[8192];
245 
246 	snprintf(cmd, sizeof(cmd), ":%s PRIVMSG %s :%s\r\n", src, dst, msg);
247 	sync_write(fd, cmd, strlen(cmd));
248 }
249 
250 void
251 irc_send_join(int fd, const char *src, const char *dst)
252 {
253 	char cmd[8192];
254 
255 	snprintf(cmd, sizeof(cmd), ":%s JOIN :%s\r\n", src, dst);
256 	sync_write(fd, cmd, strlen(cmd));
257 	in_irc_channel = 1;
258 }
259 
260 void
261 irc_send_part(int fd, const char *src, const char *dst)
262 {
263 	char cmd[8192];
264 
265 	snprintf(cmd, sizeof(cmd), ":%s PART :%s\r\n", src, dst);
266 	sync_write(fd, cmd, strlen(cmd));
267 }
268 
269 void
270 irc_send_pong(int fd, const char *daemon)
271 {
272 	char cmd[8192];
273 
274 	snprintf(cmd, sizeof(cmd), "PONG %s\r\n", daemon);
275 	sync_write(fd, cmd, strlen(cmd));
276 }