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#define FUZZ_SKIP_WRAP 1
#include "includes.h"
#include "fuzz-wrapfd.h"
#include "dbutil.h"
#include "fuzz.h"
#define IOWRAP_MAXFD (FD_SETSIZE-1)
static const int MAX_RANDOM_IN = 50000;
static const double CHANCE_CLOSE = 1.0 / 600;
static const double CHANCE_INTR = 1.0 / 900;
static const double CHANCE_READ1 = 0.96;
static const double CHANCE_READ2 = 0.5;
static const double CHANCE_WRITE1 = 0.96;
static const double CHANCE_WRITE2 = 0.5;
struct fdwrap {
enum wrapfd_mode mode;
int closein;
int closeout;
};
static struct fdwrap wrap_fds[IOWRAP_MAXFD+1] = {{UNUSED, 0, 0}};
static int wrapfd_maxfd = -1;
static unsigned short rand_state[3];
static buffer *input_buf;
static int devnull_fd = -1;
static void wrapfd_remove(int fd);
void wrapfd_setup(buffer *buf) {
TRACE(("wrapfd_setup"))
// clean old ones
int i;
for (i = 0; i <= wrapfd_maxfd; i++) {
if (wrap_fds[i].mode != UNUSED) {
wrapfd_remove(i);
}
}
wrapfd_maxfd = -1;
memset(rand_state, 0x0, sizeof(rand_state));
wrapfd_setseed(50);
input_buf = buf;
}
void wrapfd_setseed(uint32_t seed) {
memcpy(rand_state, &seed, sizeof(seed));
nrand48(rand_state);
}
int wrapfd_new_fuzzinput() {
if (devnull_fd == -1) {
devnull_fd = open("/dev/null", O_RDONLY);
assert(devnull_fd != -1);
}
int fd = dup(devnull_fd);
assert(fd != -1);
assert(wrap_fds[fd].mode == UNUSED);
wrap_fds[fd].mode = COMMONBUF;
wrap_fds[fd].closein = 0;
wrap_fds[fd].closeout = 0;
wrapfd_maxfd = MAX(fd, wrapfd_maxfd);
return fd;
}
int wrapfd_new_dummy() {
if (devnull_fd == -1) {
devnull_fd = open("/dev/null", O_RDONLY);
assert(devnull_fd != -1);
}
int fd = dup(devnull_fd);
assert(fd != -1);
assert(wrap_fds[fd].mode == UNUSED);
wrap_fds[fd].mode = DUMMY;
wrap_fds[fd].closein = 0;
wrap_fds[fd].closeout = 0;
wrapfd_maxfd = MAX(fd, wrapfd_maxfd);
return fd;
}
static void wrapfd_remove(int fd) {
TRACE(("wrapfd_remove %d", fd))
assert(fd >= 0);
assert(fd <= IOWRAP_MAXFD);
assert(wrap_fds[fd].mode != UNUSED);
wrap_fds[fd].mode = UNUSED;
m_close(fd);
}
int wrapfd_close(int fd) {
if (fd >= 0 && fd <= IOWRAP_MAXFD && wrap_fds[fd].mode != UNUSED) {
wrapfd_remove(fd);
return 0;
} else {
return close(fd);
}
}
int wrapfd_read(int fd, void *out, size_t count) {
size_t maxread;
if (!fuzz.wrapfds) {
return read(fd, out, count);
}
if (fd < 0 || fd > IOWRAP_MAXFD || wrap_fds[fd].mode == UNUSED) {
/* XXX - assertion failure? */
TRACE(("Bad read descriptor %d\n", fd))
errno = EBADF;
return -1;
}
assert(count != 0);
if (wrap_fds[fd].closein || erand48(rand_state) < CHANCE_CLOSE) {
wrap_fds[fd].closein = 1;
errno = ECONNRESET;
return -1;
}
if (erand48(rand_state) < CHANCE_INTR) {
errno = EINTR;
return -1;
}
if (input_buf && wrap_fds[fd].mode == COMMONBUF) {
maxread = MIN(input_buf->len - input_buf->pos, count);
/* returns 0 if buf is EOF, as intended */
if (maxread > 0) {
maxread = nrand48(rand_state) % maxread + 1;
}
memcpy(out, buf_getptr(input_buf, maxread), maxread);
buf_incrpos(input_buf, maxread);
return maxread;
}
// return fixed output, of random length
maxread = MIN(MAX_RANDOM_IN, count);
maxread = nrand48(rand_state) % maxread + 1;
memset(out, 0xef, maxread);
return maxread;
}
int wrapfd_write(int fd, const void* in, size_t count) {
unsigned const volatile char* volin = in;
unsigned int i;
if (!fuzz.wrapfds) {
return write(fd, in, count);
}
if (fd < 0 || fd > IOWRAP_MAXFD || wrap_fds[fd].mode == UNUSED) {
/* XXX - assertion failure? */
TRACE(("Bad read descriptor %d\n", fd))
errno = EBADF;
return -1;
}
assert(count != 0);
/* force read to exercise sanitisers */
for (i = 0; i < count; i++) {
(void)volin[i];
}
if (wrap_fds[fd].closeout || erand48(rand_state) < CHANCE_CLOSE) {
wrap_fds[fd].closeout = 1;
errno = ECONNRESET;
return -1;
}
if (erand48(rand_state) < CHANCE_INTR) {
errno = EINTR;
return -1;
}
return nrand48(rand_state) % (count+1);
}
int wrapfd_select(int nfds, fd_set *readfds, fd_set *writefds,
fd_set *exceptfds, struct timeval *timeout) {
int i, nset, sel;
int ret = 0;
int fdlist[IOWRAP_MAXFD+1];
if (!fuzz.wrapfds) {
return select(nfds, readfds, writefds, exceptfds, timeout);
}
assert(nfds <= IOWRAP_MAXFD+1);
if (erand48(rand_state) < CHANCE_INTR) {
errno = EINTR;
return -1;
}
/* read */
if (readfds != NULL && erand48(rand_state) < CHANCE_READ1) {
for (i = 0, nset = 0; i < nfds; i++) {
if (FD_ISSET(i, readfds)) {
assert(wrap_fds[i].mode != UNUSED);
fdlist[nset] = i;
nset++;
}
}
DROPBEAR_FD_ZERO(readfds);
if (nset > 0) {
/* set one */
sel = fdlist[nrand48(rand_state) % nset];
FD_SET(sel, readfds);
ret++;
if (erand48(rand_state) < CHANCE_READ2) {
sel = fdlist[nrand48(rand_state) % nset];
if (!FD_ISSET(sel, readfds)) {
FD_SET(sel, readfds);
ret++;
}
}
}
}
/* write */
if (writefds != NULL && erand48(rand_state) < CHANCE_WRITE1) {
for (i = 0, nset = 0; i < nfds; i++) {
if (FD_ISSET(i, writefds)) {
assert(wrap_fds[i].mode != UNUSED);
fdlist[nset] = i;
nset++;
}
}
DROPBEAR_FD_ZERO(writefds);
/* set one */
if (nset > 0) {
sel = fdlist[nrand48(rand_state) % nset];
FD_SET(sel, writefds);
ret++;
if (erand48(rand_state) < CHANCE_WRITE2) {
sel = fdlist[nrand48(rand_state) % nset];
if (!FD_ISSET(sel, writefds)) {
FD_SET(sel, writefds);
ret++;
}
}
}
}
return ret;
}
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