1243730Srwatson/*- 2243730Srwatson * Copyright (c) 2009-2010 The FreeBSD Foundation 3243730Srwatson * Copyright (c) 2011 Pawel Jakub Dawidek <pawel@dawidek.net> 4243730Srwatson * All rights reserved. 5243730Srwatson * 6243730Srwatson * This software was developed by Pawel Jakub Dawidek under sponsorship from 7243730Srwatson * the FreeBSD Foundation. 8243730Srwatson * 9243730Srwatson * Redistribution and use in source and binary forms, with or without 10243730Srwatson * modification, are permitted provided that the following conditions 11243730Srwatson * are met: 12243730Srwatson * 1. Redistributions of source code must retain the above copyright 13243730Srwatson * notice, this list of conditions and the following disclaimer. 14243730Srwatson * 2. Redistributions in binary form must reproduce the above copyright 15243730Srwatson * notice, this list of conditions and the following disclaimer in the 16243730Srwatson * documentation and/or other materials provided with the distribution. 17243730Srwatson * 18243730Srwatson * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 19243730Srwatson * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20243730Srwatson * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21243730Srwatson * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 22243730Srwatson * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23243730Srwatson * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24243730Srwatson * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25243730Srwatson * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26243730Srwatson * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27243730Srwatson * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28243730Srwatson * SUCH DAMAGE. 29243730Srwatson * 30243730Srwatson * $P4: //depot/projects/trustedbsd/openbsm/bin/auditdistd/proto_common.c#1 $ 31243730Srwatson */ 32243730Srwatson 33243730Srwatson#include <sys/types.h> 34243730Srwatson#include <sys/socket.h> 35243730Srwatson 36243730Srwatson#include <errno.h> 37243730Srwatson#include <fcntl.h> 38243730Srwatson#include <stdbool.h> 39243730Srwatson#include <stdlib.h> 40243730Srwatson#include <strings.h> 41243730Srwatson#include <unistd.h> 42243730Srwatson 43243730Srwatson#include <compat/compat.h> 44243730Srwatson 45243730Srwatson#include "pjdlog.h" 46243730Srwatson#include "proto_impl.h" 47243730Srwatson 48243730Srwatson/* Maximum size of packet we want to use when sending data. */ 49243730Srwatson#ifndef MAX_SEND_SIZE 50243730Srwatson#define MAX_SEND_SIZE 32768 51243730Srwatson#endif 52243730Srwatson 53243730Srwatsonstatic bool 54243730Srwatsonblocking_socket(int sock) 55243730Srwatson{ 56243730Srwatson int flags; 57243730Srwatson 58243730Srwatson flags = fcntl(sock, F_GETFL); 59243730Srwatson PJDLOG_ASSERT(flags >= 0); 60243730Srwatson return ((flags & O_NONBLOCK) == 0); 61243730Srwatson} 62243730Srwatson 63243730Srwatsonstatic int 64243730Srwatsonproto_descriptor_send(int sock, int fd) 65243730Srwatson{ 66243730Srwatson unsigned char ctrl[CMSG_SPACE(sizeof(fd))]; 67243730Srwatson struct msghdr msg; 68243730Srwatson struct cmsghdr *cmsg; 69243730Srwatson 70243730Srwatson PJDLOG_ASSERT(sock >= 0); 71243730Srwatson PJDLOG_ASSERT(fd >= 0); 72243730Srwatson 73243730Srwatson bzero(&msg, sizeof(msg)); 74243730Srwatson bzero(&ctrl, sizeof(ctrl)); 75243730Srwatson 76243730Srwatson msg.msg_iov = NULL; 77243730Srwatson msg.msg_iovlen = 0; 78243730Srwatson msg.msg_control = ctrl; 79243730Srwatson msg.msg_controllen = sizeof(ctrl); 80243730Srwatson 81243730Srwatson cmsg = CMSG_FIRSTHDR(&msg); 82243730Srwatson cmsg->cmsg_level = SOL_SOCKET; 83243730Srwatson cmsg->cmsg_type = SCM_RIGHTS; 84243730Srwatson cmsg->cmsg_len = CMSG_LEN(sizeof(fd)); 85243730Srwatson bcopy(&fd, CMSG_DATA(cmsg), sizeof(fd)); 86243730Srwatson 87243730Srwatson if (sendmsg(sock, &msg, 0) == -1) 88243730Srwatson return (errno); 89243730Srwatson 90243730Srwatson return (0); 91243730Srwatson} 92243730Srwatson 93243730Srwatsonint 94243730Srwatsonproto_common_send(int sock, const unsigned char *data, size_t size, int fd) 95243730Srwatson{ 96243730Srwatson ssize_t done; 97243730Srwatson size_t sendsize; 98243730Srwatson int errcount = 0; 99243730Srwatson 100243730Srwatson PJDLOG_ASSERT(sock >= 0); 101243730Srwatson 102243730Srwatson if (data == NULL) { 103243730Srwatson /* The caller is just trying to decide about direction. */ 104243730Srwatson 105243730Srwatson PJDLOG_ASSERT(size == 0); 106243730Srwatson 107243730Srwatson if (shutdown(sock, SHUT_RD) == -1) 108243730Srwatson return (errno); 109243730Srwatson return (0); 110243730Srwatson } 111243730Srwatson 112243730Srwatson PJDLOG_ASSERT(data != NULL); 113243730Srwatson PJDLOG_ASSERT(size > 0); 114243730Srwatson 115243730Srwatson do { 116243730Srwatson sendsize = size < MAX_SEND_SIZE ? size : MAX_SEND_SIZE; 117243730Srwatson done = send(sock, data, sendsize, MSG_NOSIGNAL); 118243730Srwatson if (done == 0) { 119243730Srwatson return (ENOTCONN); 120243730Srwatson } else if (done < 0) { 121243730Srwatson if (errno == EINTR) 122243730Srwatson continue; 123243730Srwatson if (errno == ENOBUFS) { 124243730Srwatson /* 125243730Srwatson * If there are no buffers we retry. 126243730Srwatson * After each try we increase delay before the 127243730Srwatson * next one and we give up after fifteen times. 128243730Srwatson * This gives 11s of total wait time. 129243730Srwatson */ 130243730Srwatson if (errcount == 15) { 131243730Srwatson pjdlog_warning("Getting ENOBUFS errors for 11s on send(), giving up."); 132243730Srwatson } else { 133243730Srwatson if (errcount == 0) 134243730Srwatson pjdlog_warning("Got ENOBUFS error on send(), retrying for a bit."); 135243730Srwatson errcount++; 136243730Srwatson usleep(100000 * errcount); 137243730Srwatson continue; 138243730Srwatson } 139243730Srwatson } 140243730Srwatson /* 141243730Srwatson * If this is blocking socket and we got EAGAIN, this 142243730Srwatson * means the request timed out. Translate errno to 143243730Srwatson * ETIMEDOUT, to give administrator a hint to 144243730Srwatson * eventually increase timeout. 145243730Srwatson */ 146243730Srwatson if (errno == EAGAIN && blocking_socket(sock)) 147243730Srwatson errno = ETIMEDOUT; 148243730Srwatson return (errno); 149243730Srwatson } 150243730Srwatson data += done; 151243730Srwatson size -= done; 152243730Srwatson } while (size > 0); 153243730Srwatson if (errcount > 0) { 154243730Srwatson pjdlog_info("Data sent successfully after %d ENOBUFS error%s.", 155243730Srwatson errcount, errcount == 1 ? "" : "s"); 156243730Srwatson } 157243730Srwatson 158243730Srwatson if (fd == -1) 159243730Srwatson return (0); 160243730Srwatson return (proto_descriptor_send(sock, fd)); 161243730Srwatson} 162243730Srwatson 163243730Srwatsonstatic int 164243730Srwatsonproto_descriptor_recv(int sock, int *fdp) 165243730Srwatson{ 166243730Srwatson unsigned char ctrl[CMSG_SPACE(sizeof(*fdp))]; 167243730Srwatson struct msghdr msg; 168243730Srwatson struct cmsghdr *cmsg; 169243730Srwatson 170243730Srwatson PJDLOG_ASSERT(sock >= 0); 171243730Srwatson PJDLOG_ASSERT(fdp != NULL); 172243730Srwatson 173243730Srwatson bzero(&msg, sizeof(msg)); 174243730Srwatson bzero(&ctrl, sizeof(ctrl)); 175243730Srwatson 176243730Srwatson msg.msg_iov = NULL; 177243730Srwatson msg.msg_iovlen = 0; 178243730Srwatson msg.msg_control = ctrl; 179243730Srwatson msg.msg_controllen = sizeof(ctrl); 180243730Srwatson 181243730Srwatson if (recvmsg(sock, &msg, 0) == -1) 182243730Srwatson return (errno); 183243730Srwatson 184243730Srwatson cmsg = CMSG_FIRSTHDR(&msg); 185243730Srwatson if (cmsg->cmsg_level != SOL_SOCKET || 186243730Srwatson cmsg->cmsg_type != SCM_RIGHTS) { 187243730Srwatson return (EINVAL); 188243730Srwatson } 189243730Srwatson bcopy(CMSG_DATA(cmsg), fdp, sizeof(*fdp)); 190243730Srwatson 191243730Srwatson return (0); 192243730Srwatson} 193243730Srwatson 194243730Srwatsonint 195243730Srwatsonproto_common_recv(int sock, unsigned char *data, size_t size, int *fdp) 196243730Srwatson{ 197243730Srwatson ssize_t done; 198243730Srwatson 199243730Srwatson PJDLOG_ASSERT(sock >= 0); 200243730Srwatson 201243730Srwatson if (data == NULL) { 202243730Srwatson /* The caller is just trying to decide about direction. */ 203243730Srwatson 204243730Srwatson PJDLOG_ASSERT(size == 0); 205243730Srwatson 206243730Srwatson if (shutdown(sock, SHUT_WR) == -1) 207243730Srwatson return (errno); 208243730Srwatson return (0); 209243730Srwatson } 210243730Srwatson 211243730Srwatson PJDLOG_ASSERT(data != NULL); 212243730Srwatson PJDLOG_ASSERT(size > 0); 213243730Srwatson 214243730Srwatson do { 215243730Srwatson done = recv(sock, data, size, MSG_WAITALL); 216243730Srwatson } while (done == -1 && errno == EINTR); 217243730Srwatson if (done == 0) { 218243730Srwatson return (ENOTCONN); 219243730Srwatson } else if (done < 0) { 220243730Srwatson /* 221243730Srwatson * If this is blocking socket and we got EAGAIN, this 222243730Srwatson * means the request timed out. Translate errno to 223243730Srwatson * ETIMEDOUT, to give administrator a hint to 224243730Srwatson * eventually increase timeout. 225243730Srwatson */ 226243730Srwatson if (errno == EAGAIN && blocking_socket(sock)) 227243730Srwatson errno = ETIMEDOUT; 228243730Srwatson return (errno); 229243730Srwatson } 230243730Srwatson if (fdp == NULL) 231243730Srwatson return (0); 232243730Srwatson return (proto_descriptor_recv(sock, fdp)); 233243730Srwatson} 234