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-rw-r--r--src/socket.c252
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;
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-10 02:27:38 +0000