1 files changed, 401 insertions, 0 deletions
diff --git a/libbb/xconnect.c b/libbb/xconnect.c
new file mode 100644
index 0000000..27c7424
--- /dev/null
+++ b/libbb/xconnect.c
@@ -0,0 +1,401 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Utility routines.
+ *
+ * Connect to host at port using address resolution from getaddrinfo
+ *
+ */
+
+#include <netinet/in.h>
+#include <net/if.h>
+#include "libbb.h"
+
+void FAST_FUNC setsockopt_reuseaddr(int fd)
+{
+	setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &const_int_1, sizeof(const_int_1));
+}
+int FAST_FUNC setsockopt_broadcast(int fd)
+{
+	return setsockopt(fd, SOL_SOCKET, SO_BROADCAST, &const_int_1, sizeof(const_int_1));
+}
+int FAST_FUNC setsockopt_bindtodevice(int fd, const char *iface)
+{
+	int r;
+	struct ifreq ifr;
+	strncpy(ifr.ifr_name, iface, IFNAMSIZ);
+	/* Actually, ifr_name is at offset 0, and in practice
+	 * just giving char[IFNAMSIZ] instead of struct ifreq works too.
+	 * But just in case it's not true on some obscure arch... */
+	r = setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr));
+	if (r)
+		bb_perror_msg("can't bind to interface %s", iface);
+	return r;
+}
+
+
+void FAST_FUNC xconnect(int s, const struct sockaddr *s_addr, socklen_t addrlen)
+{
+	if (connect(s, s_addr, addrlen) < 0) {
+		if (ENABLE_FEATURE_CLEAN_UP)
+			close(s);
+		if (s_addr->sa_family == AF_INET)
+			bb_perror_msg_and_die("%s (%s)",
+				"cannot connect to remote host",
+				inet_ntoa(((struct sockaddr_in *)s_addr)->sin_addr));
+		bb_perror_msg_and_die("cannot connect to remote host");
+	}
+}
+
+/* Return port number for a service.
+ * If "port" is a number use it as the port.
+ * If "port" is a name it is looked up in /etc/services, if it isnt found return
+ * default_port */
+unsigned FAST_FUNC bb_lookup_port(const char *port, const char *protocol, unsigned default_port)
+{
+	unsigned port_nr = default_port;
+	if (port) {
+		int old_errno;
+
+		/* Since this is a lib function, we're not allowed to reset errno to 0.
+		 * Doing so could break an app that is deferring checking of errno. */
+		old_errno = errno;
+		port_nr = bb_strtou(port, NULL, 10);
+		if (errno || port_nr > 65535) {
+			struct servent *tserv = getservbyname(port, protocol);
+			port_nr = default_port;
+			if (tserv)
+				port_nr = ntohs(tserv->s_port);
+		}
+		errno = old_errno;
+	}
+	return (uint16_t)port_nr;
+}
+
+
+/* "Old" networking API - only IPv4 */
+
+/*
+void FAST_FUNC bb_lookup_host(struct sockaddr_in *s_in, const char *host)
+{
+	struct hostent *he;
+
+	memset(s_in, 0, sizeof(struct sockaddr_in));
+	s_in->sin_family = AF_INET;
+	he = xgethostbyname(host);
+	memcpy(&(s_in->sin_addr), he->h_addr_list[0], he->h_length);
+}
+
+
+int FAST_FUNC xconnect_tcp_v4(struct sockaddr_in *s_addr)
+{
+	int s = xsocket(AF_INET, SOCK_STREAM, 0);
+	xconnect(s, (struct sockaddr*) s_addr, sizeof(*s_addr));
+	return s;
+}
+*/
+
+/* "New" networking API */
+
+
+int FAST_FUNC get_nport(const struct sockaddr *sa)
+{
+#if ENABLE_FEATURE_IPV6
+	if (sa->sa_family == AF_INET6) {
+		return ((struct sockaddr_in6*)sa)->sin6_port;
+	}
+#endif
+	if (sa->sa_family == AF_INET) {
+		return ((struct sockaddr_in*)sa)->sin_port;
+	}
+	/* What? UNIX socket? IPX?? :) */
+	return -1;
+}
+
+void FAST_FUNC set_nport(len_and_sockaddr *lsa, unsigned port)
+{
+#if ENABLE_FEATURE_IPV6
+	if (lsa->u.sa.sa_family == AF_INET6) {
+		lsa->u.sin6.sin6_port = port;
+		return;
+	}
+#endif
+	if (lsa->u.sa.sa_family == AF_INET) {
+		lsa->u.sin.sin_port = port;
+		return;
+	}
+	/* What? UNIX socket? IPX?? :) */
+}
+
+/* We hijack this constant to mean something else */
+/* It doesn't hurt because we will remove this bit anyway */
+#define DIE_ON_ERROR AI_CANONNAME
+
+/* host: "1.2.3.4[:port]", "www.google.com[:port]"
+ * port: if neither of above specifies port # */
+static len_and_sockaddr* str2sockaddr(
+		const char *host, int port,
+USE_FEATURE_IPV6(sa_family_t af,)
+		int ai_flags)
+{
+	int rc;
+	len_and_sockaddr *r = NULL;
+	struct addrinfo *result = NULL;
+	struct addrinfo *used_res;
+	const char *org_host = host; /* only for error msg */
+	const char *cp;
+	struct addrinfo hint;
+
+	/* Ugly parsing of host:addr */
+	if (ENABLE_FEATURE_IPV6 && host[0] == '[') {
+		/* Even uglier parsing of [xx]:nn */
+		host++;
+		cp = strchr(host, ']');
+		if (!cp || cp[1] != ':') { /* Malformed: must have [xx]:nn */
+			bb_error_msg("bad address '%s'", org_host);
+			if (ai_flags & DIE_ON_ERROR)
+				xfunc_die();
+			return NULL;
+		}
+	} else {
+		cp = strrchr(host, ':');
+		if (ENABLE_FEATURE_IPV6 && cp && strchr(host, ':') != cp) {
+			/* There is more than one ':' (e.g. "::1") */
+			cp = NULL; /* it's not a port spec */
+		}
+	}
+	if (cp) { /* points to ":" or "]:" */
+		int sz = cp - host + 1;
+		host = safe_strncpy(alloca(sz), host, sz);
+		if (ENABLE_FEATURE_IPV6 && *cp != ':')
+			cp++; /* skip ']' */
+		cp++; /* skip ':' */
+		port = bb_strtou(cp, NULL, 10);
+		if (errno || (unsigned)port > 0xffff) {
+			bb_error_msg("bad port spec '%s'", org_host);
+			if (ai_flags & DIE_ON_ERROR)
+				xfunc_die();
+			return NULL;
+		}
+	}
+
+	memset(&hint, 0 , sizeof(hint));
+#if !ENABLE_FEATURE_IPV6
+	hint.ai_family = AF_INET; /* do not try to find IPv6 */
+#else
+	hint.ai_family = af;
+#endif
+	/* Needed. Or else we will get each address thrice (or more)
+	 * for each possible socket type (tcp,udp,raw...): */
+	hint.ai_socktype = SOCK_STREAM;
+	hint.ai_flags = ai_flags & ~DIE_ON_ERROR;
+	rc = getaddrinfo(host, NULL, &hint, &result);
+	if (rc || !result) {
+		bb_error_msg("bad address '%s'", org_host);
+		if (ai_flags & DIE_ON_ERROR)
+			xfunc_die();
+		goto ret;
+	}
+	used_res = result;
+#if ENABLE_FEATURE_PREFER_IPV4_ADDRESS
+	while (1) {
+		if (used_res->ai_family == AF_INET)
+			break;
+		used_res = used_res->ai_next;
+		if (!used_res) {
+			used_res = result;
+			break;
+		}
+	}
+#endif
+	r = xmalloc(offsetof(len_and_sockaddr, u.sa) + used_res->ai_addrlen);
+	r->len = used_res->ai_addrlen;
+	memcpy(&r->u.sa, used_res->ai_addr, used_res->ai_addrlen);
+	set_nport(r, htons(port));
+ ret:
+	freeaddrinfo(result);
+	return r;
+}
+#if !ENABLE_FEATURE_IPV6
+#define str2sockaddr(host, port, af, ai_flags) str2sockaddr(host, port, ai_flags)
+#endif
+
+#if ENABLE_FEATURE_IPV6
+len_and_sockaddr* FAST_FUNC host_and_af2sockaddr(const char *host, int port, sa_family_t af)
+{
+	return str2sockaddr(host, port, af, 0);
+}
+
+len_and_sockaddr* FAST_FUNC xhost_and_af2sockaddr(const char *host, int port, sa_family_t af)
+{
+	return str2sockaddr(host, port, af, DIE_ON_ERROR);
+}
+#endif
+
+len_and_sockaddr* FAST_FUNC host2sockaddr(const char *host, int port)
+{
+	return str2sockaddr(host, port, AF_UNSPEC, 0);
+}
+
+len_and_sockaddr* FAST_FUNC xhost2sockaddr(const char *host, int port)
+{
+	return str2sockaddr(host, port, AF_UNSPEC, DIE_ON_ERROR);
+}
+
+len_and_sockaddr* FAST_FUNC xdotted2sockaddr(const char *host, int port)
+{
+	return str2sockaddr(host, port, AF_UNSPEC, AI_NUMERICHOST | DIE_ON_ERROR);
+}
+
+#undef xsocket_type
+int FAST_FUNC xsocket_type(len_and_sockaddr **lsap, USE_FEATURE_IPV6(int family,) int sock_type)
+{
+	SKIP_FEATURE_IPV6(enum { family = AF_INET };)
+	len_and_sockaddr *lsa;
+	int fd;
+	int len;
+
+#if ENABLE_FEATURE_IPV6
+	if (family == AF_UNSPEC) {
+		fd = socket(AF_INET6, sock_type, 0);
+		if (fd >= 0) {
+			family = AF_INET6;
+			goto done;
+		}
+		family = AF_INET;
+	}
+#endif
+	fd = xsocket(family, sock_type, 0);
+	len = sizeof(struct sockaddr_in);
+#if ENABLE_FEATURE_IPV6
+	if (family == AF_INET6) {
+ done:
+		len = sizeof(struct sockaddr_in6);
+	}
+#endif
+	lsa = xzalloc(offsetof(len_and_sockaddr, u.sa) + len);
+	lsa->len = len;
+	lsa->u.sa.sa_family = family;
+	*lsap = lsa;
+	return fd;
+}
+
+int FAST_FUNC xsocket_stream(len_and_sockaddr **lsap)
+{
+	return xsocket_type(lsap, USE_FEATURE_IPV6(AF_UNSPEC,) SOCK_STREAM);
+}
+
+static int create_and_bind_or_die(const char *bindaddr, int port, int sock_type)
+{
+	int fd;
+	len_and_sockaddr *lsa;
+
+	if (bindaddr && bindaddr[0]) {
+		lsa = xdotted2sockaddr(bindaddr, port);
+		/* user specified bind addr dictates family */
+		fd = xsocket(lsa->u.sa.sa_family, sock_type, 0);
+	} else {
+		fd = xsocket_type(&lsa, USE_FEATURE_IPV6(AF_UNSPEC,) sock_type);
+		set_nport(lsa, htons(port));
+	}
+	setsockopt_reuseaddr(fd);
+	xbind(fd, &lsa->u.sa, lsa->len);
+	free(lsa);
+	return fd;
+}
+
+int FAST_FUNC create_and_bind_stream_or_die(const char *bindaddr, int port)
+{
+	return create_and_bind_or_die(bindaddr, port, SOCK_STREAM);
+}
+
+int FAST_FUNC create_and_bind_dgram_or_die(const char *bindaddr, int port)
+{
+	return create_and_bind_or_die(bindaddr, port, SOCK_DGRAM);
+}
+
+
+int FAST_FUNC create_and_connect_stream_or_die(const char *peer, int port)
+{
+	int fd;
+	len_and_sockaddr *lsa;
+
+	lsa = xhost2sockaddr(peer, port);
+	fd = xsocket(lsa->u.sa.sa_family, SOCK_STREAM, 0);
+	setsockopt_reuseaddr(fd);
+	xconnect(fd, &lsa->u.sa, lsa->len);
+	free(lsa);
+	return fd;
+}
+
+int FAST_FUNC xconnect_stream(const len_and_sockaddr *lsa)
+{
+	int fd = xsocket(lsa->u.sa.sa_family, SOCK_STREAM, 0);
+	xconnect(fd, &lsa->u.sa, lsa->len);
+	return fd;
+}
+
+/* We hijack this constant to mean something else */
+/* It doesn't hurt because we will add this bit anyway */
+#define IGNORE_PORT NI_NUMERICSERV
+static char* FAST_FUNC sockaddr2str(const struct sockaddr *sa, int flags)
+{
+	char host[128];
+	char serv[16];
+	int rc;
+	socklen_t salen;
+
+	salen = LSA_SIZEOF_SA;
+#if ENABLE_FEATURE_IPV6
+	if (sa->sa_family == AF_INET)
+		salen = sizeof(struct sockaddr_in);
+	if (sa->sa_family == AF_INET6)
+		salen = sizeof(struct sockaddr_in6);
+#endif
+	rc = getnameinfo(sa, salen,
+			host, sizeof(host),
+	/* can do ((flags & IGNORE_PORT) ? NULL : serv) but why bother? */
+			serv, sizeof(serv),
+			/* do not resolve port# into service _name_ */
+			flags | NI_NUMERICSERV
+	);
+	if (rc)
+		return NULL;
+	if (flags & IGNORE_PORT)
+		return xstrdup(host);
+#if ENABLE_FEATURE_IPV6
+	if (sa->sa_family == AF_INET6) {
+		if (strchr(host, ':')) /* heh, it's not a resolved hostname */
+			return xasprintf("[%s]:%s", host, serv);
+		/*return xasprintf("%s:%s", host, serv);*/
+		/* - fall through instead */
+	}
+#endif
+	/* For now we don't support anything else, so it has to be INET */
+	/*if (sa->sa_family == AF_INET)*/
+		return xasprintf("%s:%s", host, serv);
+	/*return xstrdup(host);*/
+}
+
+char* FAST_FUNC xmalloc_sockaddr2host(const struct sockaddr *sa)
+{
+	return sockaddr2str(sa, 0);
+}
+
+char* FAST_FUNC xmalloc_sockaddr2host_noport(const struct sockaddr *sa)
+{
+	return sockaddr2str(sa, IGNORE_PORT);
+}
+
+char* FAST_FUNC xmalloc_sockaddr2hostonly_noport(const struct sockaddr *sa)
+{
+	return sockaddr2str(sa, NI_NAMEREQD | IGNORE_PORT);
+}
+char* FAST_FUNC xmalloc_sockaddr2dotted(const struct sockaddr *sa)
+{
+	return sockaddr2str(sa, NI_NUMERICHOST);
+}
+
+char* FAST_FUNC xmalloc_sockaddr2dotted_noport(const struct sockaddr *sa)
+{
+	return sockaddr2str(sa, NI_NUMERICHOST | IGNORE_PORT);
+}