forked from soccera/rdo
c80be89ef9
In sessions.h, now line 95, we used sizeof(ts_str) to determine how much to write, but as ts_str can be longer than the actual string written, it wrote random data after the actual timestamp.
138 lines
2.7 KiB
C
138 lines
2.7 KiB
C
#pragma once
|
|
|
|
#include <limits.h>
|
|
#include <errno.h>
|
|
#include <sys/types.h>
|
|
#include <sys/stat.h>
|
|
#include <fcntl.h>
|
|
#include <time.h>
|
|
|
|
int getpstartts(int pid, unsigned long long* startts) {
|
|
char path[255], fc[1024];
|
|
char* ptr = fc;
|
|
|
|
snprintf(path, sizeof(path), "/proc/%d/stat", pid);
|
|
int fd = open(path, O_RDONLY);
|
|
|
|
if (fd < 0)
|
|
err(1, "Could not open %s", path);
|
|
|
|
int bytes_read = read(fd, fc, sizeof(fc));
|
|
close(fd);
|
|
|
|
if (memchr(ptr, '\0', bytes_read) != NULL)
|
|
return -1;
|
|
|
|
ptr = strrchr(fc, ')');
|
|
|
|
char* token = strtok(ptr, " ");
|
|
|
|
for (short i = 0; i<20 && token; i++)
|
|
token = strtok(NULL, " ");
|
|
|
|
if (!token)
|
|
return -1;
|
|
|
|
unsigned long long temp_ts = strtoull(token, NULL, 10);
|
|
if (temp_ts == 0 || temp_ts == ULLONG_MAX)
|
|
return -1;
|
|
|
|
*startts = temp_ts;
|
|
return 0;
|
|
}
|
|
|
|
int gethandle(int recur) {
|
|
if (recur >= 2)
|
|
errx(1, "Too many recursions in gethandle()");
|
|
|
|
struct stat st;
|
|
int fd = open("/run/rdo", O_RDONLY, O_DIRECTORY | O_NOFOLLOW);
|
|
|
|
if (fd < 0) {
|
|
if (errno == ENOENT) {
|
|
if (mkdir("/run/rdo", 0700) < 0)
|
|
err(1, "Could not create /run/rdo");
|
|
return gethandle(++recur);
|
|
}
|
|
else
|
|
err(1, "Could not open /run/rdo");
|
|
} else {
|
|
if (fstat(fd, &st) < 0)
|
|
err(1, "Could not fstat /run/rdo");
|
|
|
|
if (st.st_uid != 0 || st.st_mode != (0700 | S_IFDIR))
|
|
return -1;
|
|
}
|
|
|
|
return fd;
|
|
}
|
|
|
|
void setsession(int pid, unsigned int ts_ttl) {
|
|
if (ts_ttl == 0)
|
|
return;
|
|
|
|
unsigned long long startts;
|
|
char path[1024], ts_str[32];
|
|
|
|
int dirfd = gethandle(0);
|
|
if (dirfd < 0 && errno == 0)
|
|
return;
|
|
|
|
if (getpstartts(pid, &startts) < 0)
|
|
return;
|
|
|
|
snprintf(path, sizeof(path), "/run/rdo/%d-%llu", pid, startts);
|
|
|
|
int fd = openat(dirfd, path, O_CREAT | O_EXCL | O_WRONLY, 0700);
|
|
if (fd < 0) {
|
|
if (errno == EEXIST)
|
|
return;
|
|
err(1, "Could not open %s", path);
|
|
}
|
|
|
|
snprintf(ts_str, sizeof(ts_str), "%llu", (unsigned long long)time(NULL));
|
|
|
|
if (write(fd, ts_str, strlen(ts_str)) < 0)
|
|
err(1, "Could not write to %s", path);
|
|
|
|
close(fd);
|
|
|
|
return;
|
|
}
|
|
|
|
int getsession(int pid, unsigned int ts_ttl) {
|
|
if (ts_ttl == 0)
|
|
return -1;
|
|
|
|
unsigned long long startts, current;
|
|
char path[1024], ts_str[32];
|
|
|
|
int dirfd = gethandle(0);
|
|
if (dirfd < 0 && errno == 0)
|
|
return -1;
|
|
|
|
if (getpstartts(pid, &startts) < 0)
|
|
return -1;
|
|
|
|
snprintf(path, sizeof(path), "/run/rdo/%d-%llu", pid, startts);
|
|
|
|
int fd = openat(dirfd, path, O_RDONLY);
|
|
if (fd < 0) {
|
|
if (errno == ENOENT)
|
|
return -1;
|
|
err(1, "Could not open %s", path);
|
|
}
|
|
|
|
if (read(fd, ts_str, sizeof(ts_str)) < 0)
|
|
err(1, "Could not read %s", path);
|
|
|
|
startts = strtoull(ts_str, NULL, 10);
|
|
current = time(NULL);
|
|
|
|
if (current - startts > ts_ttl) {
|
|
unlink(path);
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|