blob: cd38bad77be05897d3b5a3650dd1164f0611b136 [file] [log] [blame]
/*
** Copyright 2011, 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.
*/
// #define LOG_NDEBUG 0
#define LOG_TAG "qtaguid"
#include <errno.h>
#include <fcntl.h>
#include <inttypes.h>
#include <pthread.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <log/log.h>
#include <qtaguid/qtaguid.h>
static const char* CTRL_PROCPATH = "/proc/net/xt_qtaguid/ctrl";
static const int CTRL_MAX_INPUT_LEN = 128;
/*
* One per proccess.
* Once the device is open, this process will have its socket tags tracked.
* And on exit or untimely death, all socket tags will be removed.
* A process can only open /dev/xt_qtaguid once.
* It should not close it unless it is really done with all the socket tags.
* Failure to open it will be visible when socket tagging will be attempted.
*/
static int resTrackFd = -1;
pthread_once_t resTrackInitDone = PTHREAD_ONCE_INIT;
/* Only call once per process. */
void legacy_resTrack(void) {
resTrackFd = TEMP_FAILURE_RETRY(open("/dev/xt_qtaguid", O_RDONLY | O_CLOEXEC));
}
/*
* Returns:
* 0 on success.
* -errno on failure.
*/
static int write_ctrl(const char* cmd) {
int fd, res, savedErrno;
ALOGV("write_ctrl(%s)", cmd);
fd = TEMP_FAILURE_RETRY(open(CTRL_PROCPATH, O_WRONLY | O_CLOEXEC));
if (fd < 0) {
return -errno;
}
res = TEMP_FAILURE_RETRY(write(fd, cmd, strlen(cmd)));
if (res < 0) {
savedErrno = errno;
} else {
savedErrno = 0;
}
if (res < 0) {
// ALOGV is enough because all the callers also log failures
ALOGV("Failed write_ctrl(%s) res=%d errno=%d", cmd, res, savedErrno);
}
close(fd);
return -savedErrno;
}
int legacy_tagSocket(int sockfd, int tag, uid_t uid) {
char lineBuf[CTRL_MAX_INPUT_LEN];
int res;
uint64_t kTag = ((uint64_t)tag << 32);
pthread_once(&resTrackInitDone, legacy_resTrack);
snprintf(lineBuf, sizeof(lineBuf), "t %d %" PRIu64 " %d", sockfd, kTag, uid);
ALOGV("Tagging socket %d with tag %" PRIx64 "{%u,0} for uid %d", sockfd, kTag, tag, uid);
res = write_ctrl(lineBuf);
if (res < 0) {
ALOGI("Tagging socket %d with tag %" PRIx64 "(%d) for uid %d failed errno=%d", sockfd, kTag,
tag, uid, res);
}
return res;
}
int legacy_untagSocket(int sockfd) {
char lineBuf[CTRL_MAX_INPUT_LEN];
int res;
ALOGV("Untagging socket %d", sockfd);
snprintf(lineBuf, sizeof(lineBuf), "u %d", sockfd);
res = write_ctrl(lineBuf);
if (res < 0) {
ALOGI("Untagging socket %d failed errno=%d", sockfd, res);
}
return res;
}
int legacy_setCounterSet(int counterSetNum, uid_t uid) {
char lineBuf[CTRL_MAX_INPUT_LEN];
int res;
ALOGV("Setting counters to set %d for uid %d", counterSetNum, uid);
snprintf(lineBuf, sizeof(lineBuf), "s %d %d", counterSetNum, uid);
res = write_ctrl(lineBuf);
return res;
}
int legacy_deleteTagData(int tag, uid_t uid) {
char lineBuf[CTRL_MAX_INPUT_LEN];
int cnt = 0, res = 0;
uint64_t kTag = (uint64_t)tag << 32;
ALOGV("Deleting tag data with tag %" PRIx64 "{%d,0} for uid %d", kTag, tag, uid);
pthread_once(&resTrackInitDone, legacy_resTrack);
snprintf(lineBuf, sizeof(lineBuf), "d %" PRIu64 " %d", kTag, uid);
res = write_ctrl(lineBuf);
if (res < 0) {
ALOGI("Deleting tag data with tag %" PRIx64 "/%d for uid %d failed with cnt=%d errno=%d",
kTag, tag, uid, cnt, errno);
}
return res;
}