X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Fsessiond-comm%2Finet.cpp;fp=src%2Fcommon%2Fsessiond-comm%2Finet.cpp;h=20eb613a82aa2182662f65062cc6f8119871bb1d;hp=0000000000000000000000000000000000000000;hb=64efa44ea4babee85a5d855f62ca168d6aed69d0;hpb=aff3dd5c0a0de4be28db5ac7d1f8b03d5c867497

diff --git a/src/common/sessiond-comm/inet.cpp b/src/common/sessiond-comm/inet.cpp
new file mode 100644
index 000000000..20eb613a8
--- /dev/null
+++ b/src/common/sessiond-comm/inet.cpp
@@ -0,0 +1,533 @@
+/*
+ * Copyright (C) 2012 David Goulet <dgoulet@efficios.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ *
+ */
+
+#define _LGPL_SOURCE
+#include <algorithm>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <common/compat/time.h>
+#include <poll.h>
+
+#include <common/common.h>
+#include <common/time.h>
+#include <common/compat/errno.h>
+
+#include "inet.h"
+
+#define RECONNECT_DELAY	200	/* ms */
+
+/*
+ * INET protocol operations.
+ */
+static const struct lttcomm_proto_ops inet_ops = {
+	.bind = lttcomm_bind_inet_sock,
+	.close = lttcomm_close_inet_sock,
+	.connect = lttcomm_connect_inet_sock,
+	.accept = lttcomm_accept_inet_sock,
+	.listen = lttcomm_listen_inet_sock,
+	.recvmsg = lttcomm_recvmsg_inet_sock,
+	.sendmsg = lttcomm_sendmsg_inet_sock,
+};
+
+unsigned long lttcomm_inet_tcp_timeout;
+
+/*
+ * Creates an PF_INET socket.
+ */
+int lttcomm_create_inet_sock(struct lttcomm_sock *sock, int type, int proto)
+{
+	int val = 1, ret;
+	unsigned long timeout;
+
+	/* Create server socket */
+	if ((sock->fd = socket(PF_INET, type, proto)) < 0) {
+		PERROR("socket inet");
+		goto error;
+	}
+
+	sock->ops = &inet_ops;
+
+	/*
+	 * Set socket option to reuse the address.
+	 */
+	ret = setsockopt(sock->fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(int));
+	if (ret < 0) {
+		PERROR("setsockopt inet");
+		goto error;
+	}
+	timeout = lttcomm_get_network_timeout();
+	if (timeout) {
+		ret = lttcomm_setsockopt_rcv_timeout(sock->fd, timeout);
+		if (ret) {
+			goto error;
+		}
+		ret = lttcomm_setsockopt_snd_timeout(sock->fd, timeout);
+		if (ret) {
+			goto error;
+		}
+	}
+
+	return 0;
+
+error:
+	return -1;
+}
+
+/*
+ * Bind socket and return.
+ */
+int lttcomm_bind_inet_sock(struct lttcomm_sock *sock)
+{
+	struct sockaddr_in sockaddr = sock->sockaddr.addr.sin;
+
+	return bind(sock->fd, (struct sockaddr *) &sockaddr, sizeof(sockaddr));
+}
+
+static
+int connect_no_timeout(struct lttcomm_sock *sock)
+{
+	struct sockaddr_in sockaddr = sock->sockaddr.addr.sin;
+
+	return connect(sock->fd, (struct sockaddr *) &sockaddr, sizeof(sockaddr));
+}
+
+static
+int connect_with_timeout(struct lttcomm_sock *sock)
+{
+	unsigned long timeout = lttcomm_get_network_timeout();
+	int ret, flags, connect_ret;
+	struct timespec orig_time, cur_time;
+	unsigned long diff_ms;
+	struct sockaddr_in sockaddr;
+
+	ret = fcntl(sock->fd, F_GETFL, 0);
+	if (ret == -1) {
+		PERROR("fcntl");
+		return -1;
+	}
+	flags = ret;
+
+	/* Set socket to nonblock */
+	ret = fcntl(sock->fd, F_SETFL, flags | O_NONBLOCK);
+	if (ret == -1) {
+		PERROR("fcntl");
+		return -1;
+	}
+
+	ret = lttng_clock_gettime(CLOCK_MONOTONIC, &orig_time);
+	if (ret == -1) {
+		PERROR("clock_gettime");
+		return -1;
+	}
+
+	sockaddr = sock->sockaddr.addr.sin;
+	connect_ret = connect(sock->fd, (struct sockaddr *) &sockaddr, sizeof(sockaddr));
+	if (connect_ret == -1 && errno != EAGAIN && errno != EWOULDBLOCK &&
+			errno != EINPROGRESS) {
+		goto error;
+	} else if (!connect_ret) {
+		/* Connect succeeded */
+		goto success;
+	}
+
+	DBG("Asynchronous connect for sock %d, performing polling with"
+			" timeout: %lums", sock->fd, timeout);
+	/*
+	 * Perform poll loop following EINPROGRESS recommendation from
+	 * connect(2) man page.
+	 */
+	do {
+		struct pollfd fds;
+
+		fds.fd = sock->fd;
+		fds.events = POLLOUT;
+		fds.revents = 0;
+		ret = poll(&fds, 1, RECONNECT_DELAY);
+		if (ret < 0) {
+			goto error;
+		} else if (ret > 0) {
+			int optval;
+			socklen_t optval_len = sizeof(optval);
+
+			if (!(fds.revents & POLLOUT)) {
+				/* Either hup or error */
+				errno = EPIPE;
+				goto error;
+			}
+			/* got something */
+			ret = getsockopt(sock->fd, SOL_SOCKET,
+				SO_ERROR, &optval, &optval_len);
+			if (ret) {
+				PERROR("getsockopt");
+				goto error;
+			}
+			if (!optval) {
+				connect_ret = 0;
+				goto success;
+			} else {
+				/* Get actual connect() errno from opt_val */
+				errno = optval;
+				goto error;
+			}
+		}
+		/* ret == 0: timeout */
+		ret = lttng_clock_gettime(CLOCK_MONOTONIC, &cur_time);
+		if (ret == -1) {
+			PERROR("clock_gettime");
+			connect_ret = ret;
+			goto error;
+		}
+		if (timespec_to_ms(timespec_abs_diff(cur_time, orig_time), &diff_ms) < 0) {
+			ERR("timespec_to_ms input overflows milliseconds output");
+			connect_ret = -1;
+			goto error;
+		}
+	} while (diff_ms < timeout);
+
+	/* Timeout */
+	errno = ETIMEDOUT;
+	connect_ret = -1;
+
+success:
+	/* Restore initial flags */
+	ret = fcntl(sock->fd, F_SETFL, flags);
+	if (ret == -1) {
+		PERROR("fcntl");
+		/* Continue anyway */
+	}
+error:
+	return connect_ret;
+}
+
+/*
+ * Connect PF_INET socket.
+ */
+int lttcomm_connect_inet_sock(struct lttcomm_sock *sock)
+{
+	int ret, closeret;
+
+	if (lttcomm_get_network_timeout()) {
+		ret = connect_with_timeout(sock);
+	} else {
+		ret = connect_no_timeout(sock);
+	}
+	if (ret < 0) {
+		PERROR("connect");
+		goto error_connect;
+	}
+
+	return ret;
+
+error_connect:
+	closeret = close(sock->fd);
+	if (closeret) {
+		PERROR("close inet");
+	}
+
+	return ret;
+}
+
+/*
+ * Do an accept(2) on the sock and return the new lttcomm socket. The socket
+ * MUST be bind(2) before.
+ */
+struct lttcomm_sock *lttcomm_accept_inet_sock(struct lttcomm_sock *sock)
+{
+	int new_fd;
+	socklen_t len;
+	struct lttcomm_sock *new_sock;
+	unsigned long timeout;
+	struct sockaddr_in new_addr = {};
+
+	if (sock->proto == LTTCOMM_SOCK_UDP) {
+		/*
+		 * accept(2) does not exist for UDP so simply return the passed socket.
+		 */
+		new_sock = sock;
+		goto end;
+	}
+
+	new_sock = lttcomm_alloc_sock(sock->proto);
+	if (new_sock == NULL) {
+		goto error;
+	}
+
+	len = sizeof(new_addr);
+
+	/* Blocking call */
+	new_fd = accept(sock->fd, (struct sockaddr *) &new_addr, &len);
+	if (new_fd < 0) {
+		PERROR("accept inet");
+		goto error;
+	}
+	new_sock->sockaddr.addr.sin = new_addr;
+	timeout = lttcomm_get_network_timeout();
+	if (timeout) {
+		int ret;
+
+		ret = lttcomm_setsockopt_rcv_timeout(new_fd, timeout);
+		if (ret) {
+			goto error_close;
+		}
+		ret = lttcomm_setsockopt_snd_timeout(new_fd, timeout);
+		if (ret) {
+			goto error_close;
+		}
+	}
+
+	new_sock->fd = new_fd;
+	new_sock->ops = &inet_ops;
+
+end:
+	return new_sock;
+
+error_close:
+	if (close(new_fd) < 0) {
+		PERROR("accept inet close fd");
+	}
+
+error:
+	free(new_sock);
+	return NULL;
+}
+
+/*
+ * Make the socket listen using LTTNG_SESSIOND_COMM_MAX_LISTEN.
+ */
+int lttcomm_listen_inet_sock(struct lttcomm_sock *sock, int backlog)
+{
+	int ret;
+
+	if (sock->proto == LTTCOMM_SOCK_UDP) {
+		/* listen(2) does not exist for UDP so simply return success. */
+		ret = 0;
+		goto end;
+	}
+
+	/* Default listen backlog */
+	if (backlog <= 0) {
+		backlog = LTTNG_SESSIOND_COMM_MAX_LISTEN;
+	}
+
+	ret = listen(sock->fd, backlog);
+	if (ret < 0) {
+		PERROR("listen inet");
+	}
+
+end:
+	return ret;
+}
+
+/*
+ * Receive data of size len in put that data into the buf param. Using recvmsg
+ * API.
+ *
+ * Return the size of received data.
+ */
+ssize_t lttcomm_recvmsg_inet_sock(struct lttcomm_sock *sock, void *buf,
+		size_t len, int flags)
+{
+	struct msghdr msg;
+	struct iovec iov[1];
+	ssize_t ret = -1;
+	size_t len_last;
+	struct sockaddr_in addr = sock->sockaddr.addr.sin;
+
+	memset(&msg, 0, sizeof(msg));
+
+	iov[0].iov_base = buf;
+	iov[0].iov_len = len;
+	msg.msg_iov = iov;
+	msg.msg_iovlen = 1;
+
+	msg.msg_name = (struct sockaddr *) &addr;
+	msg.msg_namelen = sizeof(sock->sockaddr.addr.sin);
+
+	do {
+		len_last = iov[0].iov_len;
+		ret = recvmsg(sock->fd, &msg, flags);
+		if (ret > 0) {
+			if (flags & MSG_DONTWAIT) {
+				goto end;
+			}
+			iov[0].iov_base = ((char *) iov[0].iov_base) + ret;
+			iov[0].iov_len -= ret;
+			LTTNG_ASSERT(ret <= len_last);
+		}
+	} while ((ret > 0 && ret < len_last) || (ret < 0 && errno == EINTR));
+
+	if (ret < 0) {
+		if (errno == EAGAIN && flags & MSG_DONTWAIT) {
+			/*
+			 * EAGAIN is expected in non-blocking mode and should
+			 * not be reported as an error. Moreover, if no data
+			 * was read, 0 must not be returned as it would be
+			 * interpreted as an orderly shutdown of the socket.
+			 */
+			goto end;
+		}
+		PERROR("recvmsg inet");
+	} else if (ret > 0) {
+		ret = len;
+	}
+	/* Else ret = 0 meaning an orderly shutdown. */
+end:
+	return ret;
+}
+
+/*
+ * Send buf data of size len. Using sendmsg API.
+ *
+ * Return the size of sent data.
+ */
+ssize_t lttcomm_sendmsg_inet_sock(struct lttcomm_sock *sock, const void *buf,
+		size_t len, int flags)
+{
+	struct msghdr msg;
+	struct iovec iov[1];
+	ssize_t ret = -1;
+
+	memset(&msg, 0, sizeof(msg));
+
+	iov[0].iov_base = (void *) buf;
+	iov[0].iov_len = len;
+	msg.msg_iov = iov;
+	msg.msg_iovlen = 1;
+
+	switch (sock->proto) {
+	case LTTCOMM_SOCK_UDP:
+	{
+		struct sockaddr_in addr = sock->sockaddr.addr.sin;
+
+		msg.msg_name = (struct sockaddr *) &addr;
+		msg.msg_namelen = sizeof(sock->sockaddr.addr.sin);
+		break;
+	}
+	default:
+		break;
+	}
+
+	do {
+		ret = sendmsg(sock->fd, &msg, flags);
+	} while (ret < 0 && errno == EINTR);
+	if (ret < 0) {
+		/*
+		 * Only warn about EPIPE when quiet mode is deactivated.
+		 * We consider EPIPE as expected.
+		 */
+		if (errno != EPIPE || !lttng_opt_quiet) {
+			PERROR("sendmsg inet");
+		}
+	}
+
+	return ret;
+}
+
+/*
+ * Shutdown cleanly and close.
+ */
+int lttcomm_close_inet_sock(struct lttcomm_sock *sock)
+{
+	int ret;
+
+	/* Don't try to close an invalid marked socket */
+	if (sock->fd == -1) {
+		return 0;
+	}
+
+	ret = close(sock->fd);
+	if (ret) {
+		PERROR("close inet");
+	}
+
+	/* Mark socket */
+	sock->fd = -1;
+
+	return ret;
+}
+
+/*
+ * Return value read from /proc or else 0 if value is not found.
+ */
+static unsigned long read_proc_value(const char *path)
+{
+	int ret, fd;
+	ssize_t size_ret;
+	long r_val;
+	unsigned long val = 0;
+	char buf[64];
+
+	fd = open(path, O_RDONLY);
+	if (fd < 0) {
+		goto error;
+	}
+
+	size_ret = lttng_read(fd, buf, sizeof(buf));
+	/*
+	 * Allow reading a file smaller than buf, but keep space for
+	 * final \0.
+	 */
+	if (size_ret < 0 || size_ret >= sizeof(buf)) {
+		PERROR("read proc failed");
+		goto error_close;
+	}
+	buf[size_ret] = '\0';
+
+	errno = 0;
+	r_val = strtol(buf, NULL, 10);
+	if (errno != 0 || r_val < -1L) {
+		val = 0;
+		goto error_close;
+	} else {
+		if (r_val > 0) {
+			val = r_val;
+		}
+	}
+
+error_close:
+	ret = close(fd);
+	if (ret) {
+		PERROR("close /proc value");
+	}
+error:
+	return val;
+}
+
+void lttcomm_inet_init(void)
+{
+	unsigned long syn_retries, fin_timeout, syn_timeout, env;
+
+	env = lttcomm_get_network_timeout();
+	if (env) {
+		lttcomm_inet_tcp_timeout = env;
+		goto end;
+	}
+
+	/* Assign default value and see if we can change it. */
+	lttcomm_inet_tcp_timeout = DEFAULT_INET_TCP_TIMEOUT;
+
+	syn_retries = read_proc_value(LTTCOMM_INET_PROC_SYN_RETRIES_PATH);
+	fin_timeout = read_proc_value(LTTCOMM_INET_PROC_FIN_TIMEOUT_PATH);
+
+	syn_timeout = syn_retries * LTTCOMM_INET_SYN_TIMEOUT_FACTOR;
+
+	/*
+	 * Get the maximum between the two possible timeout value and use that to
+	 * get the maximum with the default timeout.
+	 */
+	lttcomm_inet_tcp_timeout = std::max(std::max(syn_timeout, fin_timeout),
+			lttcomm_inet_tcp_timeout);
+
+end:
+	DBG("TCP inet operation timeout set to %lu sec", lttcomm_inet_tcp_timeout);
+}