Merge branch 'feature/upstream' into develop

1 files changed, 252 insertions, 0 deletions

diff --git a/src/socket.c b/src/socket.c
index ced884a..9b5d78a 100644
--- a/src/socket.c
+++ b/src/socket.c
@@ -17,10 +17,12 @@
 #ifdef _WIN32
 #	include <ws2tcpip.h>
 #else
+#	include <fcntl.h>
 #	include <netdb.h>
 #	include <unistd.h>
 #	include <netinet/in.h>
 #	include <sys/socket.h>
+#	include <sys/stat.h>
 #endif
 #ifdef HAVE_SYS_UN_H
 #	include <sys/un.h>
@@ -46,6 +48,256 @@
 #	define AI_V4MAPPED 0
 #endif
 
+/**
+ * Return the pointer to the singular colon character, any other input
+ * yields nullptr.
+ */
+static inline const char *has_exactly_one_colon(const char *s)
+{
+	s = strchr(s, ':');
+	if (s == nullptr)
+		return nullptr;
+	return strchr(s + 1, ':') == nullptr ? s : nullptr;
+}
+
+/**
+ * @spec:	"[" HOST-ANY "]" [ ":" PORT ]
+ * 		HOST-NAME [ ":" PORT ]
+ * 		HOST-IPV4 [ ":" PORT ]
+ * 		HOST-IPV6
+ * @host:	buffer for placing the extracted hostname
+ * 		(can overlap @spec)
+ * @hsize:	buffer size for @host
+ * @port:	storage space for extracted port number
+ * 		(can be nullptr)
+ *
+ * Returns <0 (error code) if unparsable or if the output buffer is too small.
+ * Success if on >=0.
+ */
+int HX_addrport_split(const char *spec, char *host,
+    size_t hbufsz, uint16_t *pport)
+{
+	if (*spec == '[') {
+		/* We also happen to allow IPv4 addrs and hostnames in [] */
+		++spec;
+		const char *end = strchr(spec, ']');
+		if (end == nullptr)
+			return -EINVAL;
+		unsigned long hlen = end - spec;
+		if (hlen >= hbufsz)
+			return -E2BIG;
+		if (*++end == '\0')
+			return 1;
+		if (*end++ != ':')
+			return -EINVAL;
+		char *nend = nullptr;
+		uint16_t port = strtoul(end, &nend, 10);
+		if (nend == nullptr || *nend != '\0')
+			return -EINVAL;
+		memmove(host, spec, hlen);
+		host[hlen] = '\0';
+		if (pport == nullptr)
+			return 2;
+		*pport = port;
+		return 2;
+	}
+	const char *onecolon = has_exactly_one_colon(spec);
+	if (onecolon != nullptr) {
+		unsigned long hlen = onecolon - spec;
+		if (hlen >= hbufsz)
+			return -E2BIG;
+		char *nend = nullptr;
+		uint16_t port = strtoul(onecolon + 1, &nend, 10);
+		if (nend == nullptr || *nend != '\0')
+			return -EINVAL;
+		memmove(host, spec, hlen);
+		host[hlen] = '\0';
+		if (pport == nullptr)
+			return 2;
+		*pport = port;
+		return 2;
+	}
+	size_t hlen = strlen(spec);
+	if (hlen >= SIZE_MAX || ++hlen >= hbufsz)
+		return -E2BIG;
+	memmove(host, spec, hlen);
+	return 1;
+}
+
+static int HX_inet_lookup(const char *host, uint16_t port, unsigned int xflags,
+    struct addrinfo **res)
+{
+	struct addrinfo hints = {};
+#if defined(AI_V4MAPPED)
+	hints.ai_flags    = AI_V4MAPPED | xflags;
+#else
+	hints.ai_flags    = xflags;
+#endif
+	hints.ai_family   = AF_INET6;
+	hints.ai_socktype = SOCK_STREAM;
+
+	char portbuf[HXSIZEOF_Z32];
+	snprintf(portbuf, sizeof(portbuf), "%hu", port);
+	return getaddrinfo(host, port == 0 ? nullptr : portbuf, &hints, res);
+}
+
+int HX_inet_connect(const char *host, uint16_t port, unsigned int oflags)
+{
+	struct addrinfo *aires = nullptr;
+	int ret = HX_inet_lookup(host, port, AI_ADDRCONFIG, &aires);
+	int saved_errno = 0;
+	for (const struct addrinfo *r = aires; r != nullptr; r = r->ai_next) {
+		int fd = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
+		if (fd < 0) {
+			if (saved_errno == 0)
+				saved_errno = errno;
+			continue;
+		}
+#ifdef O_NONBLOCK
+		if (oflags & O_NONBLOCK) {
+			int flags = fcntl(fd, F_GETFL, 0);
+			if (flags < 0)
+				flags = 0;
+			flags |= O_NONBLOCK;
+			if (fcntl(fd, F_SETFL, flags) != 0) {
+				saved_errno = errno;
+				close(fd);
+				continue;
+			}
+		}
+#endif
+		ret = connect(fd, r->ai_addr, r->ai_addrlen);
+		if (ret == 0) {
+			freeaddrinfo(aires);
+			return fd;
+		}
+#ifdef O_NONBLOCK
+		if ((errno == EWOULDBLOCK || errno == EINPROGRESS) &&
+		    (oflags & O_NONBLOCK)) {
+			freeaddrinfo(aires);
+			return fd;
+		}
+#endif
+		saved_errno = errno;
+		close(fd);
+	}
+	if (aires == nullptr && saved_errno == 0)
+		saved_errno = EHOSTUNREACH;
+	if (aires != nullptr)
+		freeaddrinfo(aires);
+	return -(errno = saved_errno);
+}
+
+static int HX_gai_listen(const struct addrinfo *r)
+{
+	int fd = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
+	if (fd < 0)
+		return -2;
+	static const int y = 1;
+	if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, STUPIDWIN(&y), sizeof(y)) < 0)
+		/* warn setsockopt: %s, strerror(errno)) */ ;
+	int ret = bind(fd, r->ai_addr, r->ai_addrlen);
+	if (ret != 0) {
+		int se = errno;
+		close(fd);
+		errno = se;
+		return -1;
+	}
+	ret = listen(fd, SOMAXCONN);
+	if (ret != 0) {
+		int se = errno;
+		close(fd);
+		errno = se;
+		return -2;
+	}
+	return fd;
+}
+
+int HX_inet_listen(const char *host, uint16_t port)
+{
+	struct addrinfo *aires = nullptr;
+	int ret = HX_inet_lookup(host, port, AI_PASSIVE, &aires);
+	if (ret != 0)
+		;
+	int saved_errno = EHOSTUNREACH;
+	bool use_env = getenv("HX_LISTEN_TOP_FD") != nullptr || getenv("LISTEN_FDS") != nullptr;
+	for (const struct addrinfo *r = aires; r != nullptr; r = r->ai_next) {
+		if (use_env) {
+			int fd = HX_socket_from_env(r, nullptr);
+			if (fd >= 0) {
+				freeaddrinfo(aires);
+				return fd;
+			}
+		}
+		int fd = HX_gai_listen(r);
+		if (fd >= 0) {
+			freeaddrinfo(aires);
+			return fd;
+		}
+		saved_errno = errno;
+		if (fd == -2)
+			continue;
+		break;
+	}
+	if (aires != nullptr)
+		freeaddrinfo(aires);
+	return -(errno = saved_errno);
+}
+
+int HX_local_listen(const char *path)
+{
+#ifdef HAVE_SYS_UN_H
+	struct sockaddr_un u;
+	if (strlen(path) >= sizeof(u.sun_path))
+		return -EINVAL;
+	u.sun_family = AF_LOCAL;
+	strcpy(u.sun_path, path);
+	struct addrinfo r = {};
+	r.ai_flags = AI_PASSIVE;
+	r.ai_family = AF_LOCAL;
+	r.ai_socktype = SOCK_STREAM;
+	r.ai_addrlen = sizeof(u) - sizeof(u.sun_path) + strlen(u.sun_path) + 1;
+	r.ai_addr = reinterpret_cast(struct sockaddr *, &u);
+	bool use_env = getenv("HX_LISTEN_TOP_FD") != nullptr || getenv("LISTEN_FDS") != nullptr;
+	if (use_env) {
+		int fd = HX_socket_from_env(&r, nullptr);
+		if (fd >= 0)
+			return fd;
+	}
+	int ret = HX_gai_listen(&r);
+	if (ret >= 0)
+		return ret; /* fd */
+	if (ret == -2 || errno != EADDRINUSE)
+		return -errno;
+
+	struct stat sb;
+	ret = stat(path, &sb);
+	if (ret < 0)
+		return -errno;
+	if (!S_ISSOCK(sb.st_mode))
+		return -ENOTSOCK;
+
+	int testfd = socket(AF_LOCAL, SOCK_STREAM, 0);
+	if (testfd < 0)
+		return -errno;
+	ret = connect(testfd, r.ai_addr, r.ai_addrlen);
+	close(testfd);
+	if (ret == 0)
+		return -EADDRINUSE;
+
+	/* There will be a TOCTOU report, but what can you do... */
+	ret = unlink(path);
+	if (ret < 0 && errno != ENOENT)
+		return -errno;
+	ret = HX_gai_listen(&r);
+	if (ret >= 0)
+		return ret; /* fd */
+	return -errno;
+#else
+	return -EPROTONOSUPPORT;
+#endif
+}
+
 static int try_sk_from_env(int fd, const struct addrinfo *ai, const char *intf)
 {
 	int value = 0;