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#include <camellia/flags.h>
#include <camellia/syscalls.h>
#include <camellia/fs/misc.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <camellia.h>
#include <sys/param.h>
typedef struct {
hid_t sock;
} Handle;
static char *socks_addr;
static void*
fs_open(char *path, int flags) {
char *tokp;
if (*path++ != '/') {
return errno = ENOENT, NULL;
}
if (!OPEN_WRITEABLE(flags)) {
return errno = EACCES, NULL;
}
const char *verb = strtok_r(path, "/", &tokp);
if (!verb) {
return errno = ENOENT, NULL;
}
if (strcmp(verb, "connect") != 0) {
return errno = ENOSYS, NULL; // unimpl.
}
// TODO ip parsing in stdlib
// uint32_t srcip;
//if (ip_parse(strtok_r(NULL, "/", &tokp), &srcip) < 0 || srcip != 0) {
// return errno = ENOENT, NULL;
//}
strtok_r(NULL, "/", &tokp);
char *dest = strtok_r(NULL, "/", &tokp);
if (!dest) return errno = ENOENT, NULL;
size_t destlen = strlen(dest);
if (destlen >= 256) return errno = ENAMETOOLONG, NULL;
// let's assume it's a domain
char *proto = strtok_r(NULL, "/", &tokp);
if (!proto) return errno = ENOENT, NULL;
if (strcmp(proto, "tcp") != 0) {
return errno = ENOSYS, NULL; // unimpl.
}
char *port_s = strtok_r(NULL, "/", &tokp);
if (!port_s) return errno = ENOENT, NULL;
uint16_t port = strtol(port_s, NULL, 0);
Handle *h;
h = calloc(1, sizeof(*h));
if (!h) return errno = ENOMEM, NULL;
h->sock = camellia_open(socks_addr, OPEN_READ | OPEN_WRITE);
if (h->sock < 0) {
goto err;
}
/* 0x05 version 5
* 0x01 one authentication method:
* 0x00 no auth */
char buf[512];
write(h->sock, "\x05\x01\x00", 3);
errno = EGENERIC;
ssize_t ret = read(h->sock, buf, 2);
if (ret != 2) goto err; // yeah yeah i know
if (memcmp(buf, "\x05\x00", 2) != 0) goto err;
int p = 0;
buf[p++] = 5; /* v5 */
buf[p++] = 1; /* tcp connection */
buf[p++] = 0; /* reserved */
buf[p++] = 3; /* addr type, 3 = domain */
buf[p++] = destlen; /* length, max 255 */
memcpy(buf + p, dest, destlen);
p += destlen;
buf[p++] = port >> 8;
buf[p++] = port;
write(h->sock, buf, p);
ret = read(h->sock, buf, 10);
// just comparing to what tor replies, i have bigger issues than making this general
if (ret != 10 || memcmp(buf, "\x05\x00\x00\x01\x00\x00\x00\x00\x00\x00", 10) != 0) {
goto err;
}
return h;
err:
close(h->sock);
free(h);
return NULL;
}
int main(int argc, char *argv[]) {
const size_t buflen = 4096;
char *buf = malloc(buflen);
if (argc != 2) {
fprintf(stderr, "usage: socksfs /net/connect/.../\n");
return 1;
}
socks_addr = argv[1];
struct ufs_request req;
hid_t reqh;
// TODO an fs_wait flag to only wait for OPENs, and then to only wait for a given handle
// then i can use proper threads
while ((reqh = ufs_wait(buf, buflen, &req))) {
Handle *h = req.id;
switch (req.op) {
case VFSOP_OPEN: {
void *ret = fs_open(buf, req.flags);
if (ret) {
_sys_fs_respond(reqh, ret, 0, 0);
} else {
_sys_fs_respond(reqh, NULL, -errno, 0);
}
break;
}
case VFSOP_READ: {
if (_sys_fork(FORK_NOREAP, NULL) == 0) {
int len = MIN(buflen, req.capacity);
len = _sys_read(h->sock, buf, len, -1);
_sys_fs_respond(reqh, buf, len, 0);
exit(0);
} else {
close(reqh);
}
break;
}
case VFSOP_WRITE: {
if (_sys_fork(FORK_NOREAP, NULL) == 0) {
int len = _sys_write(h->sock, buf, req.len, -1, 0);
_sys_fs_respond(reqh, NULL, len, 0);
exit(0);
} else {
close(reqh);
}
break;
}
case VFSOP_CLOSE:
close(h->sock);
free(h);
_sys_fs_respond(reqh, NULL, -1, 0);
break;
default:
_sys_fs_respond(reqh, NULL, -1, 0);
break;
}
}
}
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