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#include <camellia/flags.h>
#include <camellia/syscalls.h>
#include <shared/mem.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <user/lib/fs/dir.h>
#include <user/lib/fs/misc.h>
bool fork2_n_mount(const char *path) {
handle_t h;
if (_syscall_fork(FORK_NEWFS, &h) > 0) { /* parent */
_syscall_mount(h, path, strlen(path));
close(h);
return true;
}
return false;
}
void fs_passthru(const char *prefix) {
struct fs_wait_response res;
const size_t buf_len = 1024;
char *buf = malloc(buf_len);
int prefix_len = prefix ? strlen(prefix) : 0;
if (!buf) exit(1);
while (!_syscall_fs_wait(buf, buf_len, &res)) {
switch (res.op) {
case VFSOP_OPEN:
if (prefix) {
if (prefix_len + res.len > buf_len) {
_syscall_fs_respond(NULL, -1, 0);
break;
}
// TODO memmove
char tmp[64];
memcpy(tmp, buf, res.len);
memcpy(buf + prefix_len, tmp, res.len);
memcpy(buf, prefix, prefix_len);
res.len += prefix_len;
}
_syscall_fs_respond(NULL, _syscall_open(buf, res.len, res.flags), FSR_DELEGATE);
break;
default:
_syscall_fs_respond(NULL, -1, 0);
break;
}
}
exit(0);
}
void fs_whitelist(const char **list) {
struct fs_wait_response res;
const size_t buf_len = 1024;
char *buf = malloc(buf_len);
char *ipath;
bool passthru, inject;
if (!buf) exit(1);
while (!_syscall_fs_wait(buf, buf_len, &res)) {
ipath = res.id;
switch (res.op) {
case VFSOP_OPEN:
passthru = false;
inject = false;
for (const char **iter = list; *iter; iter++) {
size_t len = strlen(*iter);
if (len <= res.len && !memcmp(buf, *iter, len)) {
passthru = true;
break;
}
if (res.len < len &&
buf[res.len - 1] == '/' &&
!memcmp(buf, *iter, res.len))
{
inject = true;
}
}
if (passthru) {
_syscall_fs_respond(NULL, _syscall_open(buf, res.len, res.flags), FSR_DELEGATE);
} else if (inject) {
// TODO all the inject points could be precomputed
ipath = malloc(res.len + 1);
memcpy(ipath, buf, res.len);
ipath[res.len] = '\0';
_syscall_fs_respond(ipath, 0, 0);
} else {
_syscall_fs_respond(NULL, -1, 0);
}
break;
case VFSOP_READ:
struct dirbuild db;
dir_start(&db, res.offset, buf, buf_len);
size_t blen = strlen(ipath);
for (const char **iter = list; *iter; iter++) {
// TODO could be precomputed too
size_t len = strlen(*iter); // inefficient, whatever
if (blen < len && !memcmp(ipath, *iter, blen))
{
/* inject up to the next slash */
// TODO separate out into its own function
int ilen = 0;
while ((*iter)[blen + ilen]) {
if ((*iter)[blen + ilen] == '/') {
ilen++;
break;
}
ilen++;
}
dir_appendl(&db, (*iter) + blen, ilen);
}
}
_syscall_fs_respond(buf, dir_finish(&db), 0);
break;
case VFSOP_CLOSE:
free(ipath);
_syscall_fs_respond(NULL, 0, 0);
break;
default:
_syscall_fs_respond(NULL, -1, 0);
break;
}
}
exit(0);
}
void fs_dir_inject(const char *path) {
struct fs_dir_handle {
const char *inject;
int delegate, inject_len;
};
const size_t path_len = strlen(path);
struct fs_wait_response res;
struct fs_dir_handle *data;
const size_t buf_len = 1024;
char *buf = malloc(buf_len);
int inject_len;
struct dirbuild db;
if (!buf) exit(1);
while (!_syscall_fs_wait(buf, buf_len, &res)) {
data = res.id;
switch (res.op) {
case VFSOP_OPEN:
if (buf[res.len - 1] == '/' &&
res.len < path_len && !memcmp(path, buf, res.len))
{
/* opening a directory that we're injecting into */
data = malloc(sizeof *data);
data->delegate = _syscall_open(buf, res.len, res.flags);
data->inject = path + res.len;
/* inject up to the next slash */
inject_len = 0;
while (data->inject[inject_len]) {
if (data->inject[inject_len] == '/') {
inject_len++; // include the slash
break;
}
inject_len++;
}
data->inject_len = inject_len;
_syscall_fs_respond(data, 0, 0);
} else {
_syscall_fs_respond(NULL, _syscall_open(buf, res.len, res.flags), FSR_DELEGATE);
}
break;
case VFSOP_CLOSE:
if (data->delegate >= 0)
close(data->delegate);
free(data);
_syscall_fs_respond(NULL, 0, 0);
break;
case VFSOP_READ:
// TODO optimization - min(buf_len, res.capacity)
dir_start(&db, res.offset, buf, buf_len);
dir_appendl(&db, data->inject, data->inject_len);
if (data->delegate >= 0)
dir_append_from(&db, data->delegate);
_syscall_fs_respond(buf, dir_finish(&db), 0);
break;
default:
_syscall_fs_respond(NULL, -1, 0);
break;
}
}
exit(0);
}
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