Merge "logd: selinux auditd initial commit"
diff --git a/logd/Android.mk b/logd/Android.mk
index b0bc746..61895c4 100644
--- a/logd/Android.mk
+++ b/logd/Android.mk
@@ -19,7 +19,9 @@
LogBufferElement.cpp \
LogTimes.cpp \
LogStatistics.cpp \
- LogWhiteBlackList.cpp
+ LogWhiteBlackList.cpp \
+ libaudit.c \
+ LogAudit.cpp
LOCAL_SHARED_LIBRARIES := \
libsysutils \
diff --git a/logd/LogAudit.cpp b/logd/LogAudit.cpp
new file mode 100644
index 0000000..cc3e583
--- /dev/null
+++ b/logd/LogAudit.cpp
@@ -0,0 +1,184 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <ctype.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <sys/klog.h>
+
+#include "libaudit.h"
+#include "LogAudit.h"
+
+LogAudit::LogAudit(LogBuffer *buf, LogReader *reader)
+ : SocketListener(getLogSocket(), false)
+ , logbuf(buf)
+ , reader(reader) {
+ logDmsg();
+}
+
+bool LogAudit::onDataAvailable(SocketClient *cli) {
+ struct audit_message rep;
+
+ if (audit_get_reply(cli->getSocket(), &rep, GET_REPLY_BLOCKING, 0) < 0) {
+ SLOGE("Failed on audit_get_reply with error: %s", strerror(errno));
+ return false;
+ }
+
+ logPrint("type=%d %.*s", rep.nlh.nlmsg_type, rep.nlh.nlmsg_len, rep.data);
+
+ return true;
+}
+
+#define AUDIT_LOG_ID LOG_ID_MAIN
+#define AUDIT_LOG_PRIO ANDROID_LOG_WARN
+
+int LogAudit::logPrint(const char *fmt, ...) {
+ if (fmt == NULL) {
+ return -EINVAL;
+ }
+
+ va_list args;
+
+ char *str = NULL;
+ va_start(args, fmt);
+ int rc = vasprintf(&str, fmt, args);
+ va_end(args);
+
+ if (rc < 0) {
+ return rc;
+ }
+
+ pid_t pid = getpid();
+ pid_t tid = gettid();
+ uid_t uid = getuid();
+ log_time now;
+
+ static const char audit_str[] = " audit(";
+ char *timeptr = strstr(str, audit_str);
+ char *cp;
+ if (timeptr
+ && ((cp = now.strptime(timeptr + sizeof(audit_str) - 1, "%s.%q")))
+ && (*cp == ':')) {
+ memcpy(timeptr + sizeof(audit_str) - 1, "0.0", 3);
+ strcpy(timeptr + sizeof(audit_str) - 1 + 3, cp);
+ } else {
+ now.strptime("", ""); // side effect of setting CLOCK_REALTIME
+ }
+
+ static const char pid_str[] = " pid=";
+ char *pidptr = strstr(str, pid_str);
+ if (pidptr && isdigit(pidptr[sizeof(pid_str) - 1])) {
+ cp = pidptr + sizeof(pid_str) - 1;
+ pid = 0;
+ while (isdigit(*cp)) {
+ pid = (pid * 10) + (*cp - '0');
+ ++cp;
+ }
+ tid = pid;
+ uid = logbuf->pidToUid(pid);
+ strcpy(pidptr, cp);
+ }
+
+ static const char comm_str[] = " comm=\"";
+ char *comm = strstr(str, comm_str);
+ if (comm) {
+ cp = comm;
+ comm += sizeof(comm_str) - 1;
+ char *ecomm = strchr(comm, '"');
+ if (ecomm) {
+ *ecomm = '\0';
+ }
+ comm = strdup(comm);
+ if (ecomm) {
+ strcpy(cp, ecomm + 1);
+ }
+ } else if (pid == getpid()) {
+ pid = tid;
+ comm = strdup("auditd");
+ } else if (!(comm = logbuf->pidToName(pid))) {
+ comm = strdup("unknown");
+ }
+
+ size_t l = strlen(comm) + 1;
+ size_t n = l + strlen(str) + 2;
+
+ char *newstr = reinterpret_cast<char *>(malloc(n));
+ if (!newstr) {
+ free(comm);
+ free(str);
+ return -ENOMEM;
+ }
+
+ *newstr = AUDIT_LOG_PRIO;
+ strcpy(newstr + 1, comm);
+ free(comm);
+ strcpy(newstr + 1 + l, str);
+ free(str);
+
+ unsigned short len = n; // cap to internal maximum
+ if (len != n) {
+ len = -1;
+ }
+ logbuf->log(AUDIT_LOG_ID, now, uid, pid, tid, newstr, len);
+ reader->notifyNewLog();
+
+ free(newstr);
+
+ return rc;
+}
+
+void LogAudit::logDmsg() {
+ int len = klogctl(KLOG_SIZE_BUFFER, NULL, 0);
+ if (len <= 0) {
+ return;
+ }
+
+ len++;
+ char buf[len];
+
+ int rc = klogctl(KLOG_READ_ALL, buf, len);
+
+ buf[len - 1] = '\0';
+
+ for(char *tok = buf; (rc >= 0) && ((tok = strtok(tok, "\r\n"))); tok = NULL) {
+ char *audit = strstr(tok, " audit(");
+ if (!audit) {
+ continue;
+ }
+
+ *audit++ = '\0';
+
+ char *type = strstr(tok, "type=");
+ if (type) {
+ rc = logPrint("%s %s", type, audit);
+ } else {
+ rc = logPrint("%s", audit);
+ }
+ }
+}
+
+int LogAudit::getLogSocket() {
+ int fd = audit_open();
+ if (fd < 0) {
+ return fd;
+ }
+ if (audit_set_pid(fd, getpid(), WAIT_YES) < 0) {
+ audit_close(fd);
+ fd = -1;
+ }
+ return fd;
+}
diff --git a/logd/LogAudit.h b/logd/LogAudit.h
new file mode 100644
index 0000000..3e57eed
--- /dev/null
+++ b/logd/LogAudit.h
@@ -0,0 +1,40 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _LOGD_LOG_AUDIT_H__
+#define _LOGD_LOG_AUDIT_H__
+
+#include <sysutils/SocketListener.h>
+#include "LogReader.h"
+
+class LogAudit : public SocketListener {
+ LogBuffer *logbuf;
+ LogReader *reader;
+
+public:
+ LogAudit(LogBuffer *buf, LogReader *reader);
+
+protected:
+ virtual bool onDataAvailable(SocketClient *cli);
+
+private:
+ static int getLogSocket();
+ void logDmsg();
+ int logPrint(const char *fmt, ...)
+ __attribute__ ((__format__ (__printf__, 2, 3)));
+};
+
+#endif
diff --git a/logd/README.auditd b/logd/README.auditd
new file mode 100644
index 0000000..3f614a3
--- /dev/null
+++ b/logd/README.auditd
@@ -0,0 +1,17 @@
+Auditd Daemon
+
+The audit daemon is a simplified version of its desktop
+counterpart designed to gather the audit logs from the
+audit kernel subsystem. The audit subsystem of the kernel
+includes Linux Security Modules (LSM) messages as well.
+
+To enable the audit subsystem, you must add this to your
+kernel config:
+CONFIG_AUDIT=y
+
+To enable a LSM, you must consult that LSM's documentation, the
+example below is for SELinux:
+CONFIG_SECURITY_SELINUX=y
+
+This does not include possible dependencies that may need to be
+satisfied for that particular LSM.
diff --git a/logd/libaudit.c b/logd/libaudit.c
new file mode 100644
index 0000000..ca88d1b
--- /dev/null
+++ b/logd/libaudit.c
@@ -0,0 +1,276 @@
+/*
+ * Copyright 2012, Samsung Telecommunications of America
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * Written by William Roberts <w.roberts@sta.samsung.com>
+ *
+ */
+
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+
+#define LOG_TAG "libaudit"
+#include <log/log.h>
+
+#include "libaudit.h"
+
+/**
+ * Waits for an ack from the kernel
+ * @param fd
+ * The netlink socket fd
+ * @param seq
+ * The current sequence number were acking on
+ * @return
+ * This function returns 0 on success, else -errno.
+ */
+static int get_ack(int fd, int16_t seq)
+{
+ int rc;
+ struct audit_message rep;
+
+ /* Sanity check, this is an internal interface this shouldn't happen */
+ if (fd < 0) {
+ return -EINVAL;
+ }
+
+ rc = audit_get_reply(fd, &rep, GET_REPLY_BLOCKING, MSG_PEEK);
+ if (rc < 0) {
+ return rc;
+ }
+
+ if (rep.nlh.nlmsg_type == NLMSG_ERROR) {
+ audit_get_reply(fd, &rep, GET_REPLY_BLOCKING, 0);
+ rc = ((struct nlmsgerr *)rep.data)->error;
+ if (rc) {
+ return -rc;
+ }
+ }
+
+ if ((int16_t)rep.nlh.nlmsg_seq != seq) {
+ SLOGW("Expected sequence number between user space and kernel space is out of skew, "
+ "expected %u got %u", seq, rep.nlh.nlmsg_seq);
+ }
+
+ return 0;
+}
+
+/**
+ *
+ * @param fd
+ * The netlink socket fd
+ * @param type
+ * The type of netlink message
+ * @param data
+ * The data to send
+ * @param size
+ * The length of the data in bytes
+ * @return
+ * This function returns a positive sequence number on success, else -errno.
+ */
+static int audit_send(int fd, int type, const void *data, size_t size)
+{
+ int rc;
+ static int16_t sequence = 0;
+ struct audit_message req;
+ struct sockaddr_nl addr;
+
+ memset(&req, 0, sizeof(req));
+ memset(&addr, 0, sizeof(addr));
+
+ /* We always send netlink messaged */
+ addr.nl_family = AF_NETLINK;
+
+ /* Set up the netlink headers */
+ req.nlh.nlmsg_type = type;
+ req.nlh.nlmsg_len = NLMSG_SPACE(size);
+ req.nlh.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
+
+ /*
+ * Check for a valid fd, even though sendto would catch this, its easier
+ * to always blindly increment the sequence number
+ */
+ if (fd < 0) {
+ return -EBADF;
+ }
+
+ /* Ensure the message is not too big */
+ if (NLMSG_SPACE(size) > MAX_AUDIT_MESSAGE_LENGTH) {
+ SLOGE("netlink message is too large");
+ return -EINVAL;
+ }
+
+ /* Only memcpy in the data if it was specified */
+ if (size && data) {
+ memcpy(NLMSG_DATA(&req.nlh), data, size);
+ }
+
+ /*
+ * Only increment the sequence number on a guarantee
+ * you will send it to the kernel.
+ *
+ * Also, the sequence is defined as a u32 in the kernel
+ * struct. Using an int here might not work on 32/64 bit splits. A
+ * signed 64 bit value can overflow a u32..but a u32
+ * might not fit in the response, so we need to use s32.
+ * Which is still kind of hackish since int could be 16 bits
+ * in size. The only safe type to use here is a signed 16
+ * bit value.
+ */
+ req.nlh.nlmsg_seq = ++sequence;
+
+ /* While failing and its due to interrupts */
+
+ rc = TEMP_FAILURE_RETRY(sendto(fd, &req, req.nlh.nlmsg_len, 0,
+ (struct sockaddr*) &addr, sizeof(addr)));
+
+ /* Not all the bytes were sent */
+ if (rc < 0) {
+ rc = -errno;
+ SLOGE("Error sending data over the netlink socket: %s", strerror(-errno));
+ goto out;
+ } else if ((uint32_t) rc != req.nlh.nlmsg_len) {
+ rc = -EPROTO;
+ goto out;
+ }
+
+ /* We sent all the bytes, get the ack */
+ rc = get_ack(fd, sequence);
+
+ /* If the ack failed, return the error, else return the sequence number */
+ rc = (rc == 0) ? (int) sequence : rc;
+
+out:
+ /* Don't let sequence roll to negative */
+ if (sequence < 0) {
+ SLOGW("Auditd to Kernel sequence number has rolled over");
+ sequence = 0;
+ }
+
+ return rc;
+}
+
+int audit_set_pid(int fd, uint32_t pid, rep_wait_t wmode)
+{
+ int rc;
+ struct audit_message rep;
+ struct audit_status status;
+
+ memset(&status, 0, sizeof(status));
+
+ /*
+ * In order to set the auditd PID we send an audit message over the netlink
+ * socket with the pid field of the status struct set to our current pid,
+ * and the the mask set to AUDIT_STATUS_PID
+ */
+ status.pid = pid;
+ status.mask = AUDIT_STATUS_PID;
+
+ /* Let the kernel know this pid will be registering for audit events */
+ rc = audit_send(fd, AUDIT_SET, &status, sizeof(status));
+ if (rc < 0) {
+ SLOGE("Could net set pid for audit events, error: %s", strerror(-rc));
+ return rc;
+ }
+
+ /*
+ * In a request where we need to wait for a response, wait for the message
+ * and discard it. This message confirms and sync's us with the kernel.
+ * This daemon is now registered as the audit logger. Only wait if the
+ * wmode is != WAIT_NO
+ */
+ if (wmode != WAIT_NO) {
+ /* TODO
+ * If the daemon dies and restarts the message didn't come back,
+ * so I went to non-blocking and it seemed to fix the bug.
+ * Need to investigate further.
+ */
+ audit_get_reply(fd, &rep, GET_REPLY_NONBLOCKING, 0);
+ }
+
+ return 0;
+}
+
+int audit_open()
+{
+ return socket(PF_NETLINK, SOCK_RAW, NETLINK_AUDIT);
+}
+
+int audit_get_reply(int fd, struct audit_message *rep, reply_t block, int peek)
+{
+ ssize_t len;
+ int flags;
+ int rc = 0;
+
+ struct sockaddr_nl nladdr;
+ socklen_t nladdrlen = sizeof(nladdr);
+
+ if (fd < 0) {
+ return -EBADF;
+ }
+
+ /* Set up the flags for recv from */
+ flags = (block == GET_REPLY_NONBLOCKING) ? MSG_DONTWAIT : 0;
+ flags |= peek;
+
+ /*
+ * Get the data from the netlink socket but on error we need to be carefull,
+ * the interface shows that EINTR can never be returned, other errors,
+ * however, can be returned.
+ */
+ len = TEMP_FAILURE_RETRY(recvfrom(fd, rep, sizeof(*rep), flags,
+ (struct sockaddr*) &nladdr, &nladdrlen));
+
+ /*
+ * EAGAIN should be re-tried until success or another error manifests.
+ */
+ if (len < 0) {
+ rc = -errno;
+ if (block == GET_REPLY_NONBLOCKING && rc == -EAGAIN) {
+ /* If request is non blocking and errno is EAGAIN, just return 0 */
+ return 0;
+ }
+ SLOGE("Error receiving from netlink socket, error: %s", strerror(-rc));
+ return rc;
+ }
+
+ if (nladdrlen != sizeof(nladdr)) {
+ SLOGE("Protocol fault, error: %s", strerror(EPROTO));
+ return -EPROTO;
+ }
+
+ /* Make sure the netlink message was not spoof'd */
+ if (nladdr.nl_pid) {
+ SLOGE("Invalid netlink pid received, expected 0 got: %d", nladdr.nl_pid);
+ return -EINVAL;
+ }
+
+ /* Check if the reply from the kernel was ok */
+ if (!NLMSG_OK(&rep->nlh, (size_t)len)) {
+ rc = (len == sizeof(*rep)) ? -EFBIG : -EBADE;
+ SLOGE("Bad kernel response %s", strerror(-rc));
+ }
+
+ return rc;
+}
+
+void audit_close(int fd)
+{
+ int rc = close(fd);
+ if (rc < 0) {
+ SLOGE("Attempting to close invalid fd %d, error: %s", fd, strerror(errno));
+ }
+ return;
+}
diff --git a/logd/libaudit.h b/logd/libaudit.h
new file mode 100644
index 0000000..cb114f9
--- /dev/null
+++ b/logd/libaudit.h
@@ -0,0 +1,104 @@
+/*
+ * Copyright 2012, Samsung Telecommunications of America
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * Written by William Roberts <w.roberts@sta.samsung.com>
+ */
+
+#ifndef _LIBAUDIT_H_
+#define _LIBAUDIT_H_
+
+#include <stdint.h>
+#include <sys/cdefs.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+
+#include <linux/netlink.h>
+#include <linux/audit.h>
+
+__BEGIN_DECLS
+
+#define MAX_AUDIT_MESSAGE_LENGTH 8970
+
+typedef enum {
+ GET_REPLY_BLOCKING=0,
+ GET_REPLY_NONBLOCKING
+} reply_t;
+
+typedef enum {
+ WAIT_NO,
+ WAIT_YES
+} rep_wait_t;
+
+/* type == AUDIT_SIGNAL_INFO */
+struct audit_sig_info {
+ uid_t uid;
+ pid_t pid;
+ char ctx[0];
+};
+
+struct audit_message {
+ struct nlmsghdr nlh;
+ char data[MAX_AUDIT_MESSAGE_LENGTH];
+};
+
+/**
+ * Opens a connection to the Audit netlink socket
+ * @return
+ * A valid fd on success or < 0 on error with errno set.
+ * Returns the same errors as man 2 socket.
+ */
+extern int audit_open(void);
+
+/**
+ * Closes the fd returned from audit_open()
+ * @param fd
+ * The fd to close
+ */
+extern void audit_close(int fd);
+
+/**
+ *
+ * @param fd
+ * The fd returned by a call to audit_open()
+ * @param rep
+ * The response struct to store the response in.
+ * @param block
+ * Whether or not to block on IO
+ * @param peek
+ * Whether or not we are to remove the message from
+ * the queue when we do a read on the netlink socket.
+ * @return
+ * This function returns 0 on success, else -errno.
+ */
+extern int audit_get_reply(int fd, struct audit_message *rep, reply_t block,
+ int peek);
+
+/**
+ * Sets a pid to recieve audit netlink events from the kernel
+ * @param fd
+ * The fd returned by a call to audit_open()
+ * @param pid
+ * The pid whom to set as the reciever of audit messages
+ * @param wmode
+ * Whether or not to block on the underlying socket io calls.
+ * @return
+ * This function returns 0 on success, -errno on error.
+ */
+extern int audit_set_pid(int fd, uint32_t pid, rep_wait_t wmode);
+
+__END_DECLS
+
+#endif
diff --git a/logd/main.cpp b/logd/main.cpp
index 8792d32..83ec6c0 100644
--- a/logd/main.cpp
+++ b/logd/main.cpp
@@ -34,6 +34,7 @@
#include "CommandListener.h"
#include "LogBuffer.h"
#include "LogListener.h"
+#include "LogAudit.h"
static int drop_privs() {
struct sched_param param;
@@ -63,7 +64,10 @@
capheader.pid = 0;
capdata[CAP_TO_INDEX(CAP_SYSLOG)].permitted = CAP_TO_MASK(CAP_SYSLOG);
- capdata[CAP_TO_INDEX(CAP_SYSLOG)].effective = CAP_TO_MASK(CAP_SYSLOG);
+ capdata[CAP_TO_INDEX(CAP_AUDIT_CONTROL)].permitted |= CAP_TO_MASK(CAP_AUDIT_CONTROL);
+
+ capdata[0].effective = capdata[0].permitted;
+ capdata[1].effective = capdata[1].permitted;
capdata[0].inheritable = 0;
capdata[1].inheritable = 0;
@@ -127,6 +131,16 @@
exit(1);
}
+ // LogAudit listens on NETLINK_AUDIT socket for selinux
+ // initiated log messages. New log entries are added to LogBuffer
+ // and LogReader is notified to send updates to connected clients.
+
+ // failure is an option ... messages are in dmesg (required by standard)
+ LogAudit *al = new LogAudit(logBuf, reader);
+ if (al->startListener()) {
+ delete al;
+ }
+
pause();
exit(0);
}