proto_common.c revision 220272
1173444Sups/*- 2173444Sups * Copyright (c) 2009-2010 The FreeBSD Foundation 3173444Sups * Copyright (c) 2011 Pawel Jakub Dawidek <pawel@dawidek.net> 4173444Sups * All rights reserved. 5173444Sups * 6173444Sups * This software was developed by Pawel Jakub Dawidek under sponsorship from 7173444Sups * the FreeBSD Foundation. 8173444Sups * 9173444Sups * Redistribution and use in source and binary forms, with or without 10173444Sups * modification, are permitted provided that the following conditions 11173444Sups * are met: 12173444Sups * 1. Redistributions of source code must retain the above copyright 13173444Sups * notice, this list of conditions and the following disclaimer. 14173444Sups * 2. Redistributions in binary form must reproduce the above copyright 15173444Sups * notice, this list of conditions and the following disclaimer in the 16173444Sups * documentation and/or other materials provided with the distribution. 17173444Sups * 18173444Sups * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 19173444Sups * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20173444Sups * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21173444Sups * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 22173444Sups * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23173444Sups * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24173444Sups * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25173444Sups * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26173444Sups * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27173444Sups * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28173444Sups * SUCH DAMAGE. 29173444Sups */ 30173444Sups 31173444Sups#include <sys/cdefs.h> 32173444Sups__FBSDID("$FreeBSD: head/sbin/hastd/proto_common.c 220272 2011-04-02 09:29:53Z pjd $"); 33173444Sups 34173444Sups#include <sys/types.h> 35173444Sups#include <sys/socket.h> 36212112Smlaier 37173444Sups#include <errno.h> 38173444Sups#include <fcntl.h> 39173444Sups#include <stdbool.h> 40173444Sups#include <stdlib.h> 41173444Sups#include <strings.h> 42193030Srwatson#include <unistd.h> 43247588Sjhb 44193030Srwatson#include "pjdlog.h" 45193030Srwatson#include "proto_impl.h" 46193030Srwatson 47212112Smlaier/* Maximum size of packet we want to use when sending data. */ 48323870Smarius#ifndef MAX_SEND_SIZE 49193030Srwatson#define MAX_SEND_SIZE 32768 50193030Srwatson#endif 51193030Srwatson 52173444Supsstatic bool 53227588Spjdblocking_socket(int sock) 54173444Sups{ 55193030Srwatson int flags; 56173444Sups 57173444Sups flags = fcntl(sock, F_GETFL); 58173444Sups PJDLOG_ASSERT(flags >= 0); 59212112Smlaier return ((flags & O_NONBLOCK) == 0); 60212112Smlaier} 61173444Sups 62193026Srwatsonstatic int 63173444Supsproto_descriptor_send(int sock, int fd) 64173444Sups{ 65173444Sups unsigned char ctrl[CMSG_SPACE(sizeof(fd))]; 66212112Smlaier struct msghdr msg; 67212112Smlaier struct cmsghdr *cmsg; 68173444Sups 69252209Sjhb PJDLOG_ASSERT(sock >= 0); 70252209Sjhb PJDLOG_ASSERT(fd >= 0); 71252209Sjhb 72252209Sjhb bzero(&msg, sizeof(msg)); 73173444Sups bzero(&ctrl, sizeof(ctrl)); 74173444Sups 75173444Sups msg.msg_iov = NULL; 76173444Sups msg.msg_iovlen = 0; 77173444Sups msg.msg_control = ctrl; 78173444Sups msg.msg_controllen = sizeof(ctrl); 79173444Sups 80173444Sups cmsg = CMSG_FIRSTHDR(&msg); 81173444Sups cmsg->cmsg_level = SOL_SOCKET; 82173444Sups cmsg->cmsg_type = SCM_RIGHTS; 83173444Sups cmsg->cmsg_len = CMSG_LEN(sizeof(fd)); 84173444Sups bcopy(&fd, CMSG_DATA(cmsg), sizeof(fd)); 85212112Smlaier 86212112Smlaier if (sendmsg(sock, &msg, 0) == -1) 87212112Smlaier return (errno); 88173444Sups 89173444Sups return (0); 90173444Sups} 91212112Smlaier 92212112Smlaierint 93212112Smlaierproto_common_send(int sock, const unsigned char *data, size_t size, int fd) 94212112Smlaier{ 95212112Smlaier ssize_t done; 96173444Sups size_t sendsize; 97252209Sjhb 98252209Sjhb PJDLOG_ASSERT(sock >= 0); 99252209Sjhb 100173444Sups if (data == NULL) { 101173444Sups /* The caller is just trying to decide about direction. */ 102173444Sups 103173444Sups PJDLOG_ASSERT(size == 0); 104193030Srwatson 105193030Srwatson if (shutdown(sock, SHUT_RD) == -1) 106193030Srwatson return (errno); 107193030Srwatson return (0); 108193030Srwatson } 109173444Sups 110173444Sups PJDLOG_ASSERT(data != NULL); 111173444Sups PJDLOG_ASSERT(size > 0); 112193030Srwatson 113173444Sups do { 114173444Sups sendsize = size < MAX_SEND_SIZE ? size : MAX_SEND_SIZE; 115173444Sups done = send(sock, data, sendsize, MSG_NOSIGNAL); 116173444Sups if (done == 0) { 117173444Sups return (ENOTCONN); 118173444Sups } else if (done < 0) { 119173444Sups if (errno == EINTR) 120173444Sups continue; 121173444Sups /* 122193030Srwatson * If this is blocking socket and we got EAGAIN, this 123193030Srwatson * means the request timed out. Translate errno to 124193030Srwatson * ETIMEDOUT, to give administrator a hint to 125193030Srwatson * eventually increase timeout. 126193030Srwatson */ 127193030Srwatson if (errno == EAGAIN && blocking_socket(sock)) 128193030Srwatson errno = ETIMEDOUT; 129193030Srwatson return (errno); 130193030Srwatson } 131193030Srwatson data += done; 132193030Srwatson size -= done; 133193030Srwatson } while (size > 0); 134252209Sjhb 135252209Sjhb if (fd == -1) 136252209Sjhb return (0); 137252209Sjhb return (proto_descriptor_send(sock, fd)); 138252209Sjhb} 139252209Sjhb 140252209Sjhbstatic int 141252209Sjhbproto_descriptor_recv(int sock, int *fdp) 142252209Sjhb{ 143252209Sjhb unsigned char ctrl[CMSG_SPACE(sizeof(*fdp))]; 144252209Sjhb struct msghdr msg; 145252209Sjhb struct cmsghdr *cmsg; 146252209Sjhb 147252209Sjhb PJDLOG_ASSERT(sock >= 0); 148252209Sjhb PJDLOG_ASSERT(fdp != NULL); 149173444Sups 150173444Sups bzero(&msg, sizeof(msg)); 151 bzero(&ctrl, sizeof(ctrl)); 152 153 msg.msg_iov = NULL; 154 msg.msg_iovlen = 0; 155 msg.msg_control = ctrl; 156 msg.msg_controllen = sizeof(ctrl); 157 158 if (recvmsg(sock, &msg, 0) == -1) 159 return (errno); 160 161 cmsg = CMSG_FIRSTHDR(&msg); 162 if (cmsg->cmsg_level != SOL_SOCKET || 163 cmsg->cmsg_type != SCM_RIGHTS) { 164 return (EINVAL); 165 } 166 bcopy(CMSG_DATA(cmsg), fdp, sizeof(*fdp)); 167 168 return (0); 169} 170 171int 172proto_common_recv(int sock, unsigned char *data, size_t size, int *fdp) 173{ 174 ssize_t done; 175 176 PJDLOG_ASSERT(sock >= 0); 177 178 if (data == NULL) { 179 /* The caller is just trying to decide about direction. */ 180 181 PJDLOG_ASSERT(size == 0); 182 183 if (shutdown(sock, SHUT_WR) == -1) 184 return (errno); 185 return (0); 186 } 187 188 PJDLOG_ASSERT(data != NULL); 189 PJDLOG_ASSERT(size > 0); 190 191 do { 192 done = recv(sock, data, size, MSG_WAITALL); 193 } while (done == -1 && errno == EINTR); 194 if (done == 0) { 195 return (ENOTCONN); 196 } else if (done < 0) { 197 /* 198 * If this is blocking socket and we got EAGAIN, this 199 * means the request timed out. Translate errno to 200 * ETIMEDOUT, to give administrator a hint to 201 * eventually increase timeout. 202 */ 203 if (errno == EAGAIN && blocking_socket(sock)) 204 errno = ETIMEDOUT; 205 return (errno); 206 } 207 if (fdp == NULL) 208 return (0); 209 return (proto_descriptor_recv(sock, fdp)); 210} 211