Add IPv6 support to pppctl by using getaddrinfo() and trying each address

it returns. This allows it to connect to the server side again, which
has been listening on IPv6 addresses exclusively for more than 2 years.

PR:		59369

1 files changed, 115 insertions, 89 deletions

diff --git a/usr.sbin/pppctl/pppctl.c b/usr.sbin/pppctl/pppctl.c
index cfc4912..1ff63b3 100644
--- a/usr.sbin/pppctl/pppctl.c
+++ b/usr.sbin/pppctl/pppctl.c
@@ -332,6 +332,29 @@ Monitor(void *v)
     return NULL;
 }
 
+static const char *
+sockaddr_ntop(const struct sockaddr *sa)
+{
+    const void *addr;
+    static char addrbuf[INET6_ADDRSTRLEN];
+ 
+    switch (sa->sa_family) {
+    case AF_INET:
+	addr = &((const struct sockaddr_in *)sa)->sin_addr;
+	break;
+    case AF_UNIX:
+	addr = &((const struct sockaddr_un *)sa)->sun_path;                
+	break;
+    case AF_INET6:
+	addr = &((const struct sockaddr_in6 *)sa)->sin6_addr;
+	break;
+    default:
+	return NULL;
+    }
+    inet_ntop(sa->sa_family, addr, addrbuf, sizeof(addrbuf));                
+    return addrbuf;
+}
+
 /*
  * Connect to ppp using either a local domain socket or a tcp socket.
  *
@@ -341,12 +364,8 @@ Monitor(void *v)
 int
 main(int argc, char **argv)
 {
-    struct servent *s;
-    struct hostent *h;
-    struct sockaddr *sock;
-    struct sockaddr_in ifsin;
     struct sockaddr_un ifsun;
-    int n, socksz, arg, fd, len, verbose, save_errno, hide1, hide1off, hide2;
+    int n, arg, fd, len, verbose, save_errno, hide1, hide1off, hide2;
     unsigned TimeoutVal;
     char *DoneWord = "x", *next, *start;
     struct sigaction act, oact;
@@ -424,9 +443,6 @@ main(int argc, char **argv)
     }
 
     if (*argv[arg] == '/') {
-        sock = (struct sockaddr *)&ifsun;
-        socksz = sizeof ifsun;
-
         memset(&ifsun, '\0', sizeof ifsun);
         ifsun.sun_len = strlen(argv[arg]);
         if (ifsun.sun_len > sizeof ifsun.sun_path - 1) {
@@ -440,88 +456,98 @@ main(int argc, char **argv)
             warnx("cannot create local domain socket");
             return 2;
         }
+	if (connect(fd, (struct sockaddr *)&ifsun, sizeof(ifsun)) < 0) {
+	    if (errno)
+		warn("cannot connect to socket %s", argv[arg]);
+	    else
+		warnx("cannot connect to socket %s", argv[arg]);
+	    close(fd);
+	    return 3;
+	}
     } else {
-        char *port, *host, *colon;
-        int hlen;
-
-        colon = strchr(argv[arg], ':');
-        if (colon) {
-            port = colon + 1;
-            *colon = '\0';
-            host = argv[arg];
-        } else {
-            port = argv[arg];
-            host = "127.0.0.1";
-        }
-        sock = (struct sockaddr *)&ifsin;
-        socksz = sizeof ifsin;
-        hlen = strlen(host);
-
-        memset(&ifsin, '\0', sizeof ifsin);
-        if (strspn(host, "0123456789.") == hlen) {
-            if (!inet_aton(host, &ifsin.sin_addr)) {
-                warnx("cannot translate %s", host);
-                return 1;
-            }
-        } else if ((h = gethostbyname(host)) == 0) {
-            warnx("cannot resolve %s", host);
-            return 1;
-        }
-        else
-            ifsin.sin_addr.s_addr = *(u_long *)h->h_addr_list[0];
-
-        if (colon)
-            *colon = ':';
-
-        if (strspn(port, "0123456789") == strlen(port))
-            ifsin.sin_port = htons(atoi(port));
-        else if (s = getservbyname(port, "tcp"), !s) {
-            warnx("%s isn't a valid port or service!", port);
-            usage();
-        }
-        else
-            ifsin.sin_port = s->s_port;
-
-        ifsin.sin_len = sizeof(ifsin);
-        ifsin.sin_family = AF_INET;
-
-        if (fd = socket(AF_INET, SOCK_STREAM, 0), fd < 0) {
-            warnx("cannot create internet socket");
-            return 2;
-        }
-    }
-
-    TimedOut = 0;
-    if (TimeoutVal) {
-        act.sa_handler = Timeout;
-        sigemptyset(&act.sa_mask);
-        act.sa_flags = 0;
-        sigaction(SIGALRM, &act, &oact);
-        alarm(TimeoutVal);
-    }
-
-    if (connect(fd, sock, socksz) < 0) {
-        if (TimeoutVal) {
-            save_errno = errno;
-            alarm(0);
-            sigaction(SIGALRM, &oact, 0);
-            errno = save_errno;
-        }
-        if (TimedOut)
-            warnx("timeout: cannot connect to socket %s", argv[arg]);
-        else {
-            if (errno)
-                warn("cannot connect to socket %s", argv[arg]);
-            else
-                warnx("cannot connect to socket %s", argv[arg]);
-        }
-        close(fd);
-        return 3;
-    }
-
-    if (TimeoutVal) {
-        alarm(0);
-        sigaction(SIGALRM, &oact, 0);
+        char *addr, *p, *port;
+	const char *caddr;
+	struct addrinfo hints, *res, *pai;
+        int gai;
+	char local[] = "localhost";
+
+	addr = argv[arg];
+	if (addr[strspn(addr, "0123456789")] == '\0') {
+	    /* port on local machine */
+	    port = addr;
+	    addr = local;
+	} else if (*addr == '[') {
+	    /* [addr]:port */
+	    if ((p = strchr(addr, ']')) == NULL) {
+		warnx("%s: mismatched '['", addr);
+		return 1;
+	    }
+	    addr++;
+	    *p++ = '\0';
+	    if (*p != ':') {
+		warnx("%s: missing port", addr);
+		return 1;
+	    }
+	    port = ++p;
+	} else {
+	    /* addr:port */
+	    p = addr + strcspn(addr, ":");
+	    if (*p != ':') {
+		warnx("%s: missing port", addr);
+		return 1;
+	    }
+	    *p++ = '\0';
+	    port = p;
+	}
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_socktype = SOCK_STREAM;
+	gai = getaddrinfo(addr, port, &hints, &res);
+	if (gai != 0) {
+	    warnx("%s: %s", addr, gai_strerror(gai));
+	    return 1;
+	}
+	for (pai = res; pai != NULL; pai = pai->ai_next) {
+	    if (fd = socket(pai->ai_family, pai->ai_socktype,
+		pai->ai_protocol), fd < 0) {
+		warnx("cannot create socket");
+		continue;
+	    }
+	    TimedOut = 0;
+	    if (TimeoutVal) {
+		act.sa_handler = Timeout;
+		sigemptyset(&act.sa_mask);
+		act.sa_flags = 0;
+		sigaction(SIGALRM, &act, &oact);
+		alarm(TimeoutVal);
+	    }
+	    if (connect(fd, pai->ai_addr, pai->ai_addrlen) == 0)
+		break;
+	    if (TimeoutVal) {
+		save_errno = errno;
+		alarm(0);
+		sigaction(SIGALRM, &oact, 0);
+		errno = save_errno;
+	    }
+	    caddr = sockaddr_ntop(pai->ai_addr);
+	    if (caddr == NULL)
+		caddr = argv[arg];
+	    if (TimedOut)
+		warnx("timeout: cannot connect to %s", caddr);
+	    else {
+		if (errno)
+		    warn("cannot connect to %s", caddr);
+		else
+		    warnx("cannot connect to %s", caddr);
+	    }
+	    close(fd);
+	}
+	freeaddrinfo(res);
+	if (pai == NULL)
+	    return 1;
+	if (TimeoutVal) {
+	    alarm(0);
+	    sigaction(SIGALRM, &oact, 0);
+	}
     }
 
     len = 0;