commit 3c9ac033392270fb6a9258d68c88d19857660143
from: Omar Polo <op@omarpolo.com>
date: Sun Jul 30 14:52:29 2023 UTC

fix IRC protocol parsing in icbirc, from Matthew Martin, ok semarie@

from the ports tree

commit - 4a7c04cc72ec15dac755ccefd619c1e722932409
commit + 3c9ac033392270fb6a9258d68c88d19857660143
blob - 239b7eb7dbd7951cbe0d6d9d72b3b3c7bcc6c515
blob + 2cb47c7d1a8a13eea3f7ec80c80e8e5b0d8c38d5
--- irc.c
+++ irc.c
@@ -42,7 +42,7 @@ extern void	 scan(const char **, char *, size_t, const
 		    const char *);
 extern int	 sync_write(int, const char *, int);
 
-static void	 irc_cmd(const char *, int, int);
+static void	 irc_cmd(char *, int, int);
 
 static void	 irc_send_pong(int, const char *);
 
@@ -93,44 +93,55 @@ irc_recv(const char *buf, unsigned len, int client_fd,
 }
 
 static void
-irc_cmd(const char *cmd, int client_fd, int server_fd)
+irc_cmd(char *cmd, int client_fd, int server_fd)
 {
-	if (!strncasecmp(cmd, "PASS ", 5)) {
-		cmd += 5;
-		scan(&cmd, irc_pass, sizeof(irc_pass), " ", " ");
-	} else if (!strncasecmp(cmd, "USER ", 5)) {
-		cmd += 5;
-		scan(&cmd, irc_ident, sizeof(irc_ident), " ", " ");
+	if (!strncasecmp(cmd, "RAWICB ", 7)) {
+		icb_send_raw(server_fd, cmd + 7);
+		return;
+	}
+
+	char *argv[10], *p;
+	int argc = 1;
+
+	for (p = cmd, argv[0] = p; argc < 10 && (p = strchr(p, ' ')) != NULL;
+	    argc++) {
+		*p = 0;
+		p++;
+		while (*p == ' ')
+			p++;
+		if (*p == ':') {
+			argv[argc] = p + 1;
+			argc++;
+			break;
+		}
+		argv[argc] = p;
+	}
+
+	if (!strcasecmp(argv[0], "PASS")) {
+		strlcpy(irc_pass, argv[1], sizeof(irc_pass));
+	} else if (!strcasecmp(argv[0], "USER")) {
+		strlcpy(irc_ident, argv[1], sizeof(irc_ident));
 		if (!icb_logged_in && irc_nick[0] && irc_ident[0])
 			icb_send_login(server_fd, irc_nick,
 			    irc_ident, irc_pass);
-	} else if (!strncasecmp(cmd, "NICK ", 5)) {
-		cmd += 5;
-		scan(&cmd, irc_nick, sizeof(irc_nick), " ", " ");
+	} else if (!strcasecmp(argv[0], "NICK")) {
+		strlcpy(irc_nick, argv[1], sizeof(irc_nick));
 		if (icb_logged_in)
 			icb_send_name(server_fd, irc_nick);
 		else if (irc_nick[0] && irc_ident[0])
 			icb_send_login(server_fd, irc_nick,
 			    irc_ident, irc_pass);
-	} else if (!strncasecmp(cmd, "JOIN ", 5)) {
-		char group[128];
-
-		cmd += 5;
-		if (*cmd == '#')
-			cmd++;
-		scan(&cmd, group, sizeof(group), " ", " ");
-		icb_send_group(server_fd, group);
-	} else if (!strncasecmp(cmd, "PART ", 5)) {
+	} else if (!strcasecmp(argv[0], "JOIN")) {
+		icb_send_group(server_fd,
+		    argv[1] + (argv[1][0] == '#' ? 1 : 0));
+	} else if (!strcasecmp(argv[0], "PART")) {
 		in_irc_channel = 0;
-	} else if (!strncasecmp(cmd, "PRIVMSG ", 8) ||
-	    !strncasecmp(cmd, "NOTICE ", 7)) {
-		char dst[128];
+	} else if (!strcasecmp(argv[0], "PRIVMSG") ||
+	    !strcasecmp(argv[0], "NOTICE")) {
 		char msg[8192];
 		unsigned i, j;
 
-		cmd += strncasecmp(cmd, "NOTICE ", 7) ? 8 : 7;
-		scan(&cmd, dst, sizeof(dst), " ", " ");
-		scan(&cmd, msg, sizeof(msg), " ", "");
+		strlcpy(msg, argv[2], sizeof(msg));
 		/* strip \001 found in CTCP messages */
 		i = 0;
 		while (msg[i]) {
@@ -141,73 +152,52 @@ irc_cmd(const char *cmd, int client_fd, int server_fd)
 			} else
 				i++;
 		}
-		if (!strcmp(dst, irc_channel))
-			icb_send_openmsg(server_fd,
-			    msg + (msg[0] == ':' ? 1 : 0));
+		if (!strcmp(argv[1], irc_channel))
+			icb_send_openmsg(server_fd, msg);
 		else
-			icb_send_privmsg(server_fd, dst,
-			    msg + (msg[0] == ':' ? 1 : 0));
-	} else if (!strncasecmp(cmd, "MODE ", 5)) {
-		cmd += 5;
-		if (!strcmp(cmd, irc_channel))
-			icb_send_names(server_fd, irc_channel);
-		else if (!strncmp(cmd, irc_channel, strlen(irc_channel))) {
-			cmd += strlen(irc_channel);
-			if (strncmp(cmd, " +o ", 4)) {
+			icb_send_privmsg(server_fd, argv[1], msg);
+	} else if (!strcasecmp(argv[0], "MODE")) {
+		if (strcmp(argv[1], irc_channel))
+			return;
+		if (argc == 2)
+			icb_send_names(server_fd, irc_channel);
+		else {
+			if (strcmp(argv[2], "+o")) {
 				printf("irc_cmd: invalid MODE args '%s'\n",
-				    cmd);
+				    argv[2]);
 				return;
 			}
-			cmd += 4;
-			icb_send_pass(server_fd, cmd);
+			icb_send_pass(server_fd, argv[3]);
 		}
-	} else if (!strncasecmp(cmd, "TOPIC ", 6)) {
-		cmd += 6;
-		if (strncmp(cmd, irc_channel, strlen(irc_channel))) {
-			printf("irc_cmd: invalid TOPIC args '%s'\n", cmd);
+	} else if (!strcasecmp(argv[0], "TOPIC")) {
+		if (strcmp(argv[1], irc_channel)) {
+			printf("irc_cmd: invalid TOPIC channel '%s'\n",
+			    argv[1]);
 			return;
 		}
-		cmd += strlen(irc_channel);
-		if (strncmp(cmd, " :", 2)) {
-			printf("irc_cmd: invalid TOPIC args '%s'\n", cmd);
-			return;
-		}
-		cmd += 2;
-		icb_send_topic(server_fd, cmd);
-	} else if (!strcasecmp(cmd, "LIST")) {
+		icb_send_topic(server_fd, argv[2]);
+	} else if (!strcasecmp(argv[0], "LIST")) {
 		icb_send_list(server_fd);
-	} else if (!strncasecmp(cmd, "NAMES ", 6)) {
-		cmd += 6;
-		icb_send_names(server_fd, cmd);
-	} else if (!strncasecmp(cmd, "WHOIS ", 6)) {
-		cmd += 6;
-		icb_send_whois(server_fd, cmd);
-	} else if (!strncasecmp(cmd, "WHO ", 4)) {
-		cmd += 4;
-		icb_send_who(server_fd, cmd);
-	} else if (!strncasecmp(cmd, "KICK ", 5)) {
-		char channel[128], nick[128];
-
-		cmd += 5;
-		scan(&cmd, channel, sizeof(channel), " ", " ");
-		scan(&cmd, nick, sizeof(nick), " ", " ");
-		if (strcmp(channel, irc_channel)) {
-			printf("irc_cmd: invalid KICK args '%s'\n", cmd);
+	} else if (!strcasecmp(argv[0], "NAMES")) {
+		icb_send_names(server_fd, argv[1]);
+	} else if (!strcasecmp(argv[0], "WHOIS")) {
+		icb_send_whois(server_fd, argv[1]);
+	} else if (!strcasecmp(argv[0], "WHO")) {
+		icb_send_who(server_fd, argv[1]);
+	} else if (!strcasecmp(argv[0], "KICK")) {
+		if (strcmp(argv[1], irc_channel)) {
+			printf("irc_cmd: invalid KICK args '%s'\n", argv[1]);
 			return;
 		}
-		icb_send_boot(server_fd, nick);
-	} else if (!strncasecmp(cmd, "PING ", 5)) {
+		icb_send_boot(server_fd, argv[2]);
+	} else if (!strcasecmp(argv[0], "PING")) {
 		icb_send_noop(server_fd);
-		cmd += 5;
-		irc_send_pong(client_fd, cmd);
-	} else if (!strncasecmp(cmd, "RAWICB ", 7)) {
-		cmd += 7;
-		icb_send_raw(server_fd, cmd);
-	} else if (!strncasecmp(cmd, "QUIT ", 5)) {
+		irc_send_pong(client_fd, argv[1]);
+	} else if (!strcasecmp(argv[0], "QUIT")) {
 		printf("client QUIT\n");
 		terminate_client = 1;
 	} else
-		printf("irc_cmd: unknown cmd '%s'\n", cmd);
+		printf("irc_cmd: unknown command '%s'\n", argv[0]);
 }
 
 void