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-rw-r--r--ct_client.c437
1 files changed, 0 insertions, 437 deletions
diff --git a/ct_client.c b/ct_client.c
deleted file mode 100644
index 37b6090..0000000
--- a/ct_client.c
+++ /dev/null
@@ -1,437 +0,0 @@
-/*
- * curvetun - the cipherspace wormhole creator
- * Part of the netsniff-ng project
- * Copyright 2011 Daniel Borkmann <daniel@netsniff-ng.org>,
- * Subject to the GPL, version 2.
- */
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include <netdb.h>
-#include <fcntl.h>
-#include <signal.h>
-#include <syslog.h>
-#include <limits.h>
-#include <netinet/in.h>
-#include <arpa/inet.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <sys/ioctl.h>
-#include <sys/stat.h>
-#include <sys/poll.h>
-#include <netinet/tcp.h>
-#include <netinet/udp.h>
-#include <linux/if_tun.h>
-
-#include "built_in.h"
-#include "die.h"
-#include "str.h"
-#include "sock.h"
-#include "ioops.h"
-#include "curve.h"
-#include "xmalloc.h"
-#include "corking.h"
-#include "ioexact.h"
-#include "curvetun.h"
-#include "ct_servmgmt.h"
-#include "ct_usermgmt.h"
-#include "crypto_auth_hmacsha512256.h"
-
-extern volatile sig_atomic_t sigint;
-static volatile sig_atomic_t closed_by_server = 0;
-
-static void handler_udp_tun_to_net(int sfd, int dfd, struct curve25519_proto *p,
- struct curve25519_struct *c, char *buff,
- size_t len)
-{
- char *cbuff;
- ssize_t rlen, clen;
- struct ct_proto *hdr;
- size_t off = sizeof(struct ct_proto) + crypto_box_zerobytes;
-
- if (!buff || len <= off)
- return;
-
- memset(buff, 0, len);
- while ((rlen = read(sfd, buff + off, len - off)) > 0) {
- hdr = (struct ct_proto *) buff;
-
- memset(hdr, 0, sizeof(*hdr));
- hdr->flags = 0;
-
- clen = curve25519_encode(c, p, (unsigned char *) (buff + off -
- crypto_box_zerobytes), (rlen +
- crypto_box_zerobytes), (unsigned char **)
- &cbuff);
- if (unlikely(clen <= 0))
- goto close;
-
- hdr->payload = htons((uint16_t) clen);
-
- set_udp_cork(dfd);
-
- write_exact(dfd, hdr, sizeof(struct ct_proto), 0);
- write_exact(dfd, cbuff, clen, 0);
-
- set_udp_uncork(dfd);
-
- memset(buff, 0, len);
- }
-
- return;
-close:
- closed_by_server = 1;
-}
-
-static void handler_udp_net_to_tun(int sfd, int dfd, struct curve25519_proto *p,
- struct curve25519_struct *c, char *buff,
- size_t len)
-{
- char *cbuff;
- ssize_t rlen, clen;
- struct ct_proto *hdr;
- struct sockaddr_storage naddr;
-
- socklen_t nlen = sizeof(naddr);
-
- if (!buff || !len)
- return;
-
- memset(&naddr, 0, sizeof(naddr));
- while ((rlen = recvfrom(sfd, buff, len, 0, (struct sockaddr *) &naddr,
- &nlen)) > 0) {
- hdr = (struct ct_proto *) buff;
-
- if (unlikely(rlen < sizeof(struct ct_proto)))
- goto close;
- if (unlikely(rlen - sizeof(*hdr) != ntohs(hdr->payload)))
- goto close;
- if (unlikely(ntohs(hdr->payload) == 0))
- goto close;
- if (hdr->flags & PROTO_FLAG_EXIT)
- goto close;
-
- clen = curve25519_decode(c, p, (unsigned char *) buff +
- sizeof(struct ct_proto),
- rlen - sizeof(struct ct_proto),
- (unsigned char **) &cbuff, NULL);
- if (unlikely(clen <= 0))
- goto close;
-
- cbuff += crypto_box_zerobytes;
- clen -= crypto_box_zerobytes;
-
- if (write(dfd, cbuff, clen)) { ; }
- }
-
- return;
-close:
- closed_by_server = 1;
-}
-
-static void handler_tcp_tun_to_net(int sfd, int dfd, struct curve25519_proto *p,
- struct curve25519_struct *c, char *buff,
- size_t len)
-{
- char *cbuff;
- ssize_t rlen, clen;
- struct ct_proto *hdr;
- size_t off = sizeof(struct ct_proto) + crypto_box_zerobytes;
-
- if (!buff || len <= off)
- return;
-
- memset(buff, 0, len);
- while ((rlen = read(sfd, buff + off, len - off)) > 0) {
- hdr = (struct ct_proto *) buff;
-
- memset(hdr, 0, sizeof(*hdr));
- hdr->flags = 0;
-
- clen = curve25519_encode(c, p, (unsigned char *) (buff + off -
- crypto_box_zerobytes), (rlen +
- crypto_box_zerobytes), (unsigned char **)
- &cbuff);
- if (unlikely(clen <= 0))
- goto close;
-
- hdr->payload = htons((uint16_t) clen);
-
- set_tcp_cork(dfd);
-
- write_exact(dfd, hdr, sizeof(struct ct_proto), 0);
- write_exact(dfd, cbuff, clen, 0);
-
- set_tcp_uncork(dfd);
-
- memset(buff, 0, len);
- }
-
- return;
-close:
- closed_by_server = 1;
-}
-
-extern ssize_t handler_tcp_read(int fd, char *buff, size_t len);
-
-static void handler_tcp_net_to_tun(int sfd, int dfd, struct curve25519_proto *p,
- struct curve25519_struct *c, char *buff,
- size_t len)
-{
- char *cbuff;
- ssize_t rlen, clen;
- struct ct_proto *hdr;
-
- if (!buff || !len)
- return;
-
- while ((rlen = handler_tcp_read(sfd, buff, len)) > 0) {
- hdr = (struct ct_proto *) buff;
-
- if (unlikely(rlen < sizeof(struct ct_proto)))
- goto close;
- if (unlikely(rlen - sizeof(*hdr) != ntohs(hdr->payload)))
- goto close;
- if (unlikely(ntohs(hdr->payload) == 0))
- goto close;
- if (hdr->flags & PROTO_FLAG_EXIT)
- goto close;
-
- clen = curve25519_decode(c, p, (unsigned char *) buff +
- sizeof(struct ct_proto),
- rlen - sizeof(struct ct_proto),
- (unsigned char **) &cbuff, NULL);
- if (unlikely(clen <= 0))
- goto close;
-
- cbuff += crypto_box_zerobytes;
- clen -= crypto_box_zerobytes;
-
- if (write(dfd, cbuff, clen)) { ; }
- }
-
- return;
-close:
- closed_by_server = 1;
-}
-
-static void notify_init(int fd, int udp, struct curve25519_proto *p,
- struct curve25519_struct *c, char *home)
-{
- int fd2, i;
- ssize_t err, clen;
- size_t us_len, msg_len, pad;
- struct ct_proto hdr;
- char username[256], path[PATH_MAX], *us, *cbuff, *msg;
- unsigned char auth[crypto_auth_hmacsha512256_BYTES], *token;
-
- memset(&hdr, 0, sizeof(hdr));
- hdr.flags |= PROTO_FLAG_INIT;
-
- memset(path, 0, sizeof(path));
- slprintf(path, sizeof(path), "%s/%s", home, FILE_USERNAM);
-
- fd2 = open_or_die(path, O_RDONLY);
-
- memset(username, 0, sizeof(username));
- err = read(fd2, username, sizeof(username));
- username[sizeof(username) - 1] = 0;
-
- close(fd2);
-
- token = get_serv_store_entry_auth_token();
- if (!token)
- syslog_panic("Cannot find auth token for server!\n");
-
- us_len = sizeof(struct username_struct) + crypto_box_zerobytes;
- us = xzmalloc(us_len);
-
- err = username_msg(username, strlen(username) + 1,
- us + crypto_box_zerobytes,
- us_len - crypto_box_zerobytes);
- if (unlikely(err))
- syslog_panic("Cannot create init message!\n");
-
- clen = curve25519_encode(c, p, (unsigned char *) us, us_len,
- (unsigned char **) &cbuff);
- if (unlikely(clen <= 0))
- syslog_panic("Init encrypt error!\n");
-
- err = crypto_auth_hmacsha512256(auth, (unsigned char *) cbuff, clen, token);
- if (unlikely(err))
- syslog_panic("Cannot create init hmac message!\n");
-
- pad = ((uint32_t) secrand()) % 200;
- msg_len = clen + sizeof(auth) + pad;
-
- msg = xzmalloc(msg_len);
- memcpy(msg, auth, sizeof(auth));
- memcpy(msg + sizeof(auth), cbuff, clen);
-
- for (i = sizeof(auth) + clen; i < msg_len; ++i)
- msg[i] = (uint8_t) secrand();
-
- hdr.payload = htons((uint16_t) msg_len);
-
- set_sock_cork(fd, udp);
-
- write_exact(fd, &hdr, sizeof(struct ct_proto), 0);
- write_exact(fd, msg, msg_len, 0);
-
- set_sock_uncork(fd, udp);
-
- xfree(msg);
- xfree(us);
-}
-
-static void notify_close(int fd)
-{
- struct ct_proto hdr;
-
- memset(&hdr, 0, sizeof(hdr));
-
- hdr.flags |= PROTO_FLAG_EXIT;
- hdr.payload = 0;
-
- write_exact(fd, &hdr, sizeof(hdr), 0);
-}
-
-int client_main(char *home, char *dev, char *host, char *port, int udp)
-{
- int fd = -1, tunfd = 0, retry_server = 0;
- int ret, try = 1, i;
- struct addrinfo hints, *ahead, *ai;
- struct pollfd fds[2];
- struct curve25519_proto *p;
- struct curve25519_struct *c;
- char *buff;
- size_t blen = TUNBUFF_SIZ; //FIXME
-
-retry:
- if (!retry_server) {
- openlog("curvetun", LOG_PID | LOG_CONS | LOG_NDELAY, LOG_DAEMON);
- syslog(LOG_INFO, "curvetun client booting!\n");
- }
-
- c = curve25519_tfm_alloc();
- p = get_serv_store_entry_proto_inf();
- if (!p)
- syslog_panic("Cannot proto!\n");
-
- memset(&hints, 0, sizeof(hints));
- hints.ai_family = PF_UNSPEC;
- hints.ai_socktype = udp ? SOCK_DGRAM : SOCK_STREAM;
- hints.ai_protocol = udp ? IPPROTO_UDP : IPPROTO_TCP;
- hints.ai_flags = AI_NUMERICSERV;
-
- ret = getaddrinfo(host, port, &hints, &ahead);
- if (ret < 0) {
- syslog(LOG_ERR, "Cannot get address info! Retry!\n");
- curve25519_tfm_free(c);
- fd = -1;
- retry_server = 1;
- closed_by_server = 0;
- sleep(1);
- goto retry;
- }
-
- for (ai = ahead; ai != NULL && fd < 0; ai = ai->ai_next) {
- fd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
- if (fd < 0)
- continue;
- ret = connect(fd, ai->ai_addr, ai->ai_addrlen);
- if (ret < 0) {
- syslog(LOG_ERR, "Cannot connect to remote, try %d: %s!\n",
- try++, strerror(errno));
- close(fd);
- fd = -1;
- continue;
- }
-
- set_socket_keepalive(fd);
- set_mtu_disc_dont(fd);
- if (!udp)
- set_tcp_nodelay(fd);
- }
-
- freeaddrinfo(ahead);
-
- if (fd < 0) {
- syslog(LOG_ERR, "Cannot create socket! Retry!\n");
- curve25519_tfm_free(c);
- fd = -1;
- retry_server = 1;
- closed_by_server = 0;
- sleep(1);
- goto retry;
- }
-
- if (!retry_server)
- tunfd = tun_open_or_die(dev ? dev : DEVNAME_CLIENT,
- IFF_TUN | IFF_NO_PI);
-
- set_nonblocking_sloppy(fd);
- set_nonblocking_sloppy(tunfd);
-
- memset(fds, 0, sizeof(fds));
- fds[0].fd = fd;
- fds[1].fd = tunfd;
- fds[0].events = POLLIN;
- fds[1].events = POLLIN;
-
- buff = xmalloc_aligned(blen, 64);
-
- notify_init(fd, udp, p, c, home);
-
- syslog(LOG_INFO, "curvetun client ready!\n");
-
- while (likely(!sigint && !closed_by_server)) {
- poll(fds, 2, -1);
- for (i = 0; i < 2; ++i) {
- if ((fds[i].revents & POLLIN) != POLLIN)
- continue;
- if (fds[i].fd == tunfd) {
- if (udp)
- handler_udp_tun_to_net(tunfd, fd, p, c,
- buff, blen);
- else
- handler_tcp_tun_to_net(tunfd, fd, p, c,
- buff, blen);
- } else if (fds[i].fd == fd) {
- if (udp)
- handler_udp_net_to_tun(fd, tunfd, p, c,
- buff, blen);
- else
- handler_tcp_net_to_tun(fd, tunfd, p, c,
- buff, blen);
- }
- }
- }
-
- syslog(LOG_INFO, "curvetun client prepare shut down!\n");
-
- if (!closed_by_server)
- notify_close(fd);
-
- xfree(buff);
- close(fd);
- curve25519_tfm_free(c);
-
- /* tundev still active */
- if (closed_by_server && !sigint) {
- syslog(LOG_ERR, "curvetun connection retry attempt!\n");
- fd = -1;
- retry_server = 1;
- closed_by_server = 0;
- sleep(1);
- goto retry;
- }
-
- close(tunfd);
- syslog(LOG_INFO, "curvetun client shut down!\n");
- closelog();
-
- return 0;
-}
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