1204076Spjd/*- 2330449Seadler * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3330449Seadler * 4204076Spjd * Copyright (c) 2009-2010 The FreeBSD Foundation 5220272Spjd * Copyright (c) 2011 Pawel Jakub Dawidek <pawel@dawidek.net> 6204076Spjd * All rights reserved. 7204076Spjd * 8204076Spjd * This software was developed by Pawel Jakub Dawidek under sponsorship from 9204076Spjd * the FreeBSD Foundation. 10204076Spjd * 11204076Spjd * Redistribution and use in source and binary forms, with or without 12204076Spjd * modification, are permitted provided that the following conditions 13204076Spjd * are met: 14204076Spjd * 1. Redistributions of source code must retain the above copyright 15204076Spjd * notice, this list of conditions and the following disclaimer. 16204076Spjd * 2. Redistributions in binary form must reproduce the above copyright 17204076Spjd * notice, this list of conditions and the following disclaimer in the 18204076Spjd * documentation and/or other materials provided with the distribution. 19204076Spjd * 20204076Spjd * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 21204076Spjd * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22204076Spjd * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23204076Spjd * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 24204076Spjd * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25204076Spjd * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26204076Spjd * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27204076Spjd * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28204076Spjd * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29204076Spjd * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30204076Spjd * SUCH DAMAGE. 31204076Spjd */ 32204076Spjd 33204076Spjd#include <sys/cdefs.h> 34204076Spjd__FBSDID("$FreeBSD: stable/11/sbin/hastd/proto_common.c 330449 2018-03-05 07:26:05Z eadler $"); 35204076Spjd 36204076Spjd#include <sys/types.h> 37204076Spjd#include <sys/socket.h> 38204076Spjd 39204076Spjd#include <errno.h> 40220272Spjd#include <fcntl.h> 41220272Spjd#include <stdbool.h> 42204076Spjd#include <stdlib.h> 43204076Spjd#include <strings.h> 44220272Spjd#include <unistd.h> 45204076Spjd 46218138Spjd#include "pjdlog.h" 47204076Spjd#include "proto_impl.h" 48204076Spjd 49204076Spjd/* Maximum size of packet we want to use when sending data. */ 50204076Spjd#ifndef MAX_SEND_SIZE 51211452Spjd#define MAX_SEND_SIZE 32768 52204076Spjd#endif 53204076Spjd 54220272Spjdstatic bool 55220272Spjdblocking_socket(int sock) 56220272Spjd{ 57220272Spjd int flags; 58220272Spjd 59220272Spjd flags = fcntl(sock, F_GETFL); 60220272Spjd PJDLOG_ASSERT(flags >= 0); 61220272Spjd return ((flags & O_NONBLOCK) == 0); 62220272Spjd} 63220272Spjd 64218194Spjdstatic int 65218194Spjdproto_descriptor_send(int sock, int fd) 66204076Spjd{ 67218139Spjd unsigned char ctrl[CMSG_SPACE(sizeof(fd))]; 68218139Spjd struct msghdr msg; 69218139Spjd struct cmsghdr *cmsg; 70218139Spjd 71218139Spjd PJDLOG_ASSERT(sock >= 0); 72218139Spjd PJDLOG_ASSERT(fd >= 0); 73218139Spjd 74218139Spjd bzero(&msg, sizeof(msg)); 75218139Spjd bzero(&ctrl, sizeof(ctrl)); 76218139Spjd 77218139Spjd msg.msg_iov = NULL; 78218139Spjd msg.msg_iovlen = 0; 79218139Spjd msg.msg_control = ctrl; 80218139Spjd msg.msg_controllen = sizeof(ctrl); 81218139Spjd 82218139Spjd cmsg = CMSG_FIRSTHDR(&msg); 83218139Spjd cmsg->cmsg_level = SOL_SOCKET; 84218139Spjd cmsg->cmsg_type = SCM_RIGHTS; 85218139Spjd cmsg->cmsg_len = CMSG_LEN(sizeof(fd)); 86218148Spjd bcopy(&fd, CMSG_DATA(cmsg), sizeof(fd)); 87218139Spjd 88218139Spjd if (sendmsg(sock, &msg, 0) == -1) 89218139Spjd return (errno); 90218139Spjd 91218139Spjd return (0); 92218139Spjd} 93218139Spjd 94218139Spjdint 95218194Spjdproto_common_send(int sock, const unsigned char *data, size_t size, int fd) 96218139Spjd{ 97218194Spjd ssize_t done; 98218194Spjd size_t sendsize; 99220273Spjd int errcount = 0; 100218194Spjd 101218194Spjd PJDLOG_ASSERT(sock >= 0); 102220270Spjd 103220270Spjd if (data == NULL) { 104220270Spjd /* The caller is just trying to decide about direction. */ 105220270Spjd 106220270Spjd PJDLOG_ASSERT(size == 0); 107220270Spjd 108220270Spjd if (shutdown(sock, SHUT_RD) == -1) 109220270Spjd return (errno); 110220270Spjd return (0); 111220270Spjd } 112220270Spjd 113218194Spjd PJDLOG_ASSERT(data != NULL); 114218194Spjd PJDLOG_ASSERT(size > 0); 115218194Spjd 116218194Spjd do { 117218194Spjd sendsize = size < MAX_SEND_SIZE ? size : MAX_SEND_SIZE; 118218194Spjd done = send(sock, data, sendsize, MSG_NOSIGNAL); 119220272Spjd if (done == 0) { 120218194Spjd return (ENOTCONN); 121229945Spjd } else if (done == -1) { 122218194Spjd if (errno == EINTR) 123218194Spjd continue; 124220273Spjd if (errno == ENOBUFS) { 125220273Spjd /* 126220273Spjd * If there are no buffers we retry. 127220273Spjd * After each try we increase delay before the 128220273Spjd * next one and we give up after fifteen times. 129220273Spjd * This gives 11s of total wait time. 130220273Spjd */ 131220273Spjd if (errcount == 15) { 132220273Spjd pjdlog_warning("Getting ENOBUFS errors for 11s on send(), giving up."); 133220273Spjd } else { 134220273Spjd if (errcount == 0) 135220273Spjd pjdlog_warning("Got ENOBUFS error on send(), retrying for a bit."); 136220273Spjd errcount++; 137220273Spjd usleep(100000 * errcount); 138220273Spjd continue; 139220273Spjd } 140220273Spjd } 141220272Spjd /* 142220272Spjd * If this is blocking socket and we got EAGAIN, this 143220272Spjd * means the request timed out. Translate errno to 144220272Spjd * ETIMEDOUT, to give administrator a hint to 145220272Spjd * eventually increase timeout. 146220272Spjd */ 147220272Spjd if (errno == EAGAIN && blocking_socket(sock)) 148220272Spjd errno = ETIMEDOUT; 149218194Spjd return (errno); 150218194Spjd } 151218194Spjd data += done; 152218194Spjd size -= done; 153218194Spjd } while (size > 0); 154220273Spjd if (errcount > 0) { 155220273Spjd pjdlog_info("Data sent successfully after %d ENOBUFS error%s.", 156220273Spjd errcount, errcount == 1 ? "" : "s"); 157220273Spjd } 158218194Spjd 159218194Spjd if (fd == -1) 160218194Spjd return (0); 161218194Spjd return (proto_descriptor_send(sock, fd)); 162218194Spjd} 163218194Spjd 164218194Spjdstatic int 165218194Spjdproto_descriptor_recv(int sock, int *fdp) 166218194Spjd{ 167218139Spjd unsigned char ctrl[CMSG_SPACE(sizeof(*fdp))]; 168218139Spjd struct msghdr msg; 169218139Spjd struct cmsghdr *cmsg; 170218139Spjd 171218139Spjd PJDLOG_ASSERT(sock >= 0); 172218139Spjd PJDLOG_ASSERT(fdp != NULL); 173218139Spjd 174218139Spjd bzero(&msg, sizeof(msg)); 175218139Spjd bzero(&ctrl, sizeof(ctrl)); 176218139Spjd 177218139Spjd msg.msg_iov = NULL; 178218139Spjd msg.msg_iovlen = 0; 179218139Spjd msg.msg_control = ctrl; 180218139Spjd msg.msg_controllen = sizeof(ctrl); 181218139Spjd 182218139Spjd if (recvmsg(sock, &msg, 0) == -1) 183218139Spjd return (errno); 184218139Spjd 185218148Spjd cmsg = CMSG_FIRSTHDR(&msg); 186237931Spjd if (cmsg == NULL || cmsg->cmsg_level != SOL_SOCKET || 187218194Spjd cmsg->cmsg_type != SCM_RIGHTS) { 188218148Spjd return (EINVAL); 189218139Spjd } 190218148Spjd bcopy(CMSG_DATA(cmsg), fdp, sizeof(*fdp)); 191218139Spjd 192218148Spjd return (0); 193218139Spjd} 194218194Spjd 195218194Spjdint 196218194Spjdproto_common_recv(int sock, unsigned char *data, size_t size, int *fdp) 197218194Spjd{ 198218194Spjd ssize_t done; 199218194Spjd 200218194Spjd PJDLOG_ASSERT(sock >= 0); 201220270Spjd 202220270Spjd if (data == NULL) { 203220270Spjd /* The caller is just trying to decide about direction. */ 204220270Spjd 205220270Spjd PJDLOG_ASSERT(size == 0); 206220270Spjd 207220270Spjd if (shutdown(sock, SHUT_WR) == -1) 208220270Spjd return (errno); 209220270Spjd return (0); 210220270Spjd } 211220270Spjd 212218194Spjd PJDLOG_ASSERT(data != NULL); 213218194Spjd PJDLOG_ASSERT(size > 0); 214218194Spjd 215218194Spjd do { 216223143Ssobomax done = recv(sock, data, size, MSG_WAITALL); 217223143Ssobomax } while (done == -1 && errno == EINTR); 218220272Spjd if (done == 0) { 219218194Spjd return (ENOTCONN); 220229945Spjd } else if (done == -1) { 221220272Spjd /* 222220272Spjd * If this is blocking socket and we got EAGAIN, this 223220272Spjd * means the request timed out. Translate errno to 224220272Spjd * ETIMEDOUT, to give administrator a hint to 225220272Spjd * eventually increase timeout. 226220272Spjd */ 227220272Spjd if (errno == EAGAIN && blocking_socket(sock)) 228220272Spjd errno = ETIMEDOUT; 229218194Spjd return (errno); 230220272Spjd } 231218194Spjd if (fdp == NULL) 232218194Spjd return (0); 233218194Spjd return (proto_descriptor_recv(sock, fdp)); 234218194Spjd} 235