diff options
Diffstat (limited to 'bin/auditdistd/proto_common.c')
| -rw-r--r-- | bin/auditdistd/proto_common.c | 233 |
1 files changed, 233 insertions, 0 deletions
diff --git a/bin/auditdistd/proto_common.c b/bin/auditdistd/proto_common.c new file mode 100644 index 000000000000..0fa4d3c5443b --- /dev/null +++ b/bin/auditdistd/proto_common.c @@ -0,0 +1,233 @@ +/*- + * Copyright (c) 2009-2010 The FreeBSD Foundation + * Copyright (c) 2011 Pawel Jakub Dawidek <pawel@dawidek.net> + * All rights reserved. + * + * This software was developed by Pawel Jakub Dawidek under sponsorship from + * the FreeBSD Foundation. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * $P4: //depot/projects/trustedbsd/openbsm/bin/auditdistd/proto_common.c#1 $ + */ + +#include <sys/types.h> +#include <sys/socket.h> + +#include <errno.h> +#include <fcntl.h> +#include <stdbool.h> +#include <stdlib.h> +#include <strings.h> +#include <unistd.h> + +#include <compat/compat.h> + +#include "pjdlog.h" +#include "proto_impl.h" + +/* Maximum size of packet we want to use when sending data. */ +#ifndef MAX_SEND_SIZE +#define MAX_SEND_SIZE 32768 +#endif + +static bool +blocking_socket(int sock) +{ + int flags; + + flags = fcntl(sock, F_GETFL); + PJDLOG_ASSERT(flags >= 0); + return ((flags & O_NONBLOCK) == 0); +} + +static int +proto_descriptor_send(int sock, int fd) +{ + unsigned char ctrl[CMSG_SPACE(sizeof(fd))]; + struct msghdr msg; + struct cmsghdr *cmsg; + + PJDLOG_ASSERT(sock >= 0); + PJDLOG_ASSERT(fd >= 0); + + bzero(&msg, sizeof(msg)); + bzero(&ctrl, sizeof(ctrl)); + + msg.msg_iov = NULL; + msg.msg_iovlen = 0; + msg.msg_control = ctrl; + msg.msg_controllen = sizeof(ctrl); + + cmsg = CMSG_FIRSTHDR(&msg); + cmsg->cmsg_level = SOL_SOCKET; + cmsg->cmsg_type = SCM_RIGHTS; + cmsg->cmsg_len = CMSG_LEN(sizeof(fd)); + bcopy(&fd, CMSG_DATA(cmsg), sizeof(fd)); + + if (sendmsg(sock, &msg, 0) == -1) + return (errno); + + return (0); +} + +int +proto_common_send(int sock, const unsigned char *data, size_t size, int fd) +{ + ssize_t done; + size_t sendsize; + int errcount = 0; + + PJDLOG_ASSERT(sock >= 0); + + if (data == NULL) { + /* The caller is just trying to decide about direction. */ + + PJDLOG_ASSERT(size == 0); + + if (shutdown(sock, SHUT_RD) == -1) + return (errno); + return (0); + } + + PJDLOG_ASSERT(data != NULL); + PJDLOG_ASSERT(size > 0); + + do { + sendsize = size < MAX_SEND_SIZE ? size : MAX_SEND_SIZE; + done = send(sock, data, sendsize, MSG_NOSIGNAL); + if (done == 0) { + return (ENOTCONN); + } else if (done < 0) { + if (errno == EINTR) + continue; + if (errno == ENOBUFS) { + /* + * If there are no buffers we retry. + * After each try we increase delay before the + * next one and we give up after fifteen times. + * This gives 11s of total wait time. + */ + if (errcount == 15) { + pjdlog_warning("Getting ENOBUFS errors for 11s on send(), giving up."); + } else { + if (errcount == 0) + pjdlog_warning("Got ENOBUFS error on send(), retrying for a bit."); + errcount++; + usleep(100000 * errcount); + continue; + } + } + /* + * If this is blocking socket and we got EAGAIN, this + * means the request timed out. Translate errno to + * ETIMEDOUT, to give administrator a hint to + * eventually increase timeout. + */ + if (errno == EAGAIN && blocking_socket(sock)) + errno = ETIMEDOUT; + return (errno); + } + data += done; + size -= done; + } while (size > 0); + if (errcount > 0) { + pjdlog_info("Data sent successfully after %d ENOBUFS error%s.", + errcount, errcount == 1 ? "" : "s"); + } + + if (fd == -1) + return (0); + return (proto_descriptor_send(sock, fd)); +} + +static int +proto_descriptor_recv(int sock, int *fdp) +{ + unsigned char ctrl[CMSG_SPACE(sizeof(*fdp))]; + struct msghdr msg; + struct cmsghdr *cmsg; + + PJDLOG_ASSERT(sock >= 0); + PJDLOG_ASSERT(fdp != NULL); + + bzero(&msg, sizeof(msg)); + bzero(&ctrl, sizeof(ctrl)); + + msg.msg_iov = NULL; + msg.msg_iovlen = 0; + msg.msg_control = ctrl; + msg.msg_controllen = sizeof(ctrl); + + if (recvmsg(sock, &msg, 0) == -1) + return (errno); + + cmsg = CMSG_FIRSTHDR(&msg); + if (cmsg->cmsg_level != SOL_SOCKET || + cmsg->cmsg_type != SCM_RIGHTS) { + return (EINVAL); + } + bcopy(CMSG_DATA(cmsg), fdp, sizeof(*fdp)); + + return (0); +} + +int +proto_common_recv(int sock, unsigned char *data, size_t size, int *fdp) +{ + ssize_t done; + + PJDLOG_ASSERT(sock >= 0); + + if (data == NULL) { + /* The caller is just trying to decide about direction. */ + + PJDLOG_ASSERT(size == 0); + + if (shutdown(sock, SHUT_WR) == -1) + return (errno); + return (0); + } + + PJDLOG_ASSERT(data != NULL); + PJDLOG_ASSERT(size > 0); + + do { + done = recv(sock, data, size, MSG_WAITALL); + } while (done == -1 && errno == EINTR); + if (done == 0) { + return (ENOTCONN); + } else if (done < 0) { + /* + * If this is blocking socket and we got EAGAIN, this + * means the request timed out. Translate errno to + * ETIMEDOUT, to give administrator a hint to + * eventually increase timeout. + */ + if (errno == EAGAIN && blocking_socket(sock)) + errno = ETIMEDOUT; + return (errno); + } + if (fdp == NULL) + return (0); + return (proto_descriptor_recv(sock, fdp)); +} |