C++ (Cpp) remove_user_by_socket示例

示例#1

文件： curvetun_server.c 项目： christophjaeger/netsniff-ng

static int handler_tcp_net_to_tun(int fd, const struct worker_struct *ws,
				  char *buff, size_t len)
{
	int keep = 1, count = 0;
	char *cbuff;
	ssize_t rlen, err, clen;
	struct ct_proto *hdr;
	struct curve25519_proto *p;

	if (!buff || !len)
		return 0;

	while ((rlen = handler_tcp_read(fd, buff, len)) > 0) {
		p = NULL;

		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) {
close:
			remove_user_by_socket(fd);
			trie_addr_remove(fd);
			handler_tcp_notify_close(fd);
			rlen = write(ws->parent.efd, &fd, sizeof(fd));

			keep = 0;
			return keep;
		}
		if (hdr->flags & PROTO_FLAG_INIT) {
			syslog_maybe(auth_log, LOG_INFO, "Got initial userhash "
				     "from remote end!\n");

			if (unlikely(rlen - sizeof(*hdr) <
				     sizeof(struct username_struct)))
				goto close;

			err = try_register_user_by_socket(ws->c,
					buff + sizeof(struct ct_proto),
					rlen - sizeof(struct ct_proto),
					fd, auth_log);
			if (unlikely(err))
				goto close;

			continue;
		}

		err = get_user_by_socket(fd, &p);
		if (unlikely(err || !p))
			continue;

		clen = curve25519_decode(ws->c, p, (unsigned char *) buff +
					 sizeof(struct ct_proto),
					 rlen - sizeof(struct ct_proto),
					 (unsigned char **) &cbuff, NULL);
                if (unlikely(clen <= 0))
			continue;

		cbuff += crypto_box_zerobytes;
		clen -= crypto_box_zerobytes;

		err = trie_addr_maybe_update(cbuff, clen, ws->parent.ipv4,
					     fd, NULL, 0);
		if (unlikely(err))
			continue;

		err = write(ws->parent.tunfd, cbuff, clen);

		count++;
		if (count == 10) {
			write_exact(ws->efd[1], &fd, sizeof(fd), 1);
			/* Read later next data and let others process */
			return keep;
		}
	}

	return keep;
}

示例#2

文件： ct_server.c 项目： candinico/netsniff-ng

static int handler_tcp_net_to_tun(int fd, const struct worker_struct *ws,
				  char *buff, size_t len)
{
	int keep = 1, count = 0;
	char *cbuff;
	ssize_t rlen, err, clen;
	struct ct_proto *hdr;
	struct curve25519_proto *p;

	if (!buff || !len)  {
		errno = EINVAL;
		return 0;
	}

	errno = 0;
	while ((rlen = handler_tcp_read(fd, buff, len)) > 0) {
		p = NULL;
		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) {
close:
			remove_user_by_socket(fd);
			trie_addr_remove(fd);
			handler_tcp_notify_close(fd);
			rlen = write(ws->parent.efd, &fd, sizeof(fd));
			if (rlen != sizeof(fd))
				syslog(LOG_ERR, "CPU%u: TCP event write error: %s\n",
				       ws->cpu, strerror(errno));
			keep = 0;
			return keep;
		}
		if (hdr->flags & PROTO_FLAG_INIT) {
			if (auth_log)
				syslog(LOG_INFO, "Got initial userhash from remote end!\n");
			if (unlikely(rlen - sizeof(*hdr) <
				     sizeof(struct username_struct)))
				goto close;
			err = try_register_user_by_socket(ws->c, buff + sizeof(struct ct_proto),
							  rlen - sizeof(struct ct_proto),
							  fd, auth_log);
			if (unlikely(err))
				goto close;
			continue;
		}

		err = get_user_by_socket(fd, &p);
		if (unlikely(err || !p)) {
			syslog(LOG_ERR, "CPU%u: User protocol not in cache! "
			       "Dropping connection!\n", ws->cpu);
			goto close;
		}
		clen = curve25519_decode(ws->c, p, (unsigned char *) buff +
					 sizeof(struct ct_proto),
					 rlen - sizeof(struct ct_proto),
					 (unsigned char **) &cbuff, NULL);
                if (unlikely(clen <= 0)) {
			syslog(LOG_ERR, "CPU%u: TCP net decryption error: %zd\n",
			       ws->cpu, clen);
			goto close;
		}
		cbuff += crypto_box_zerobytes;
		clen -= crypto_box_zerobytes;
		err = trie_addr_maybe_update(cbuff, clen, ws->parent.ipv4,
					     fd, NULL, 0);
		if (unlikely(err)) {
			syslog(LOG_INFO, "CPU%u: Malicious packet dropped "
			       "from id %d\n", ws->cpu, fd);
			continue;
		}

		err = write(ws->parent.tunfd, cbuff, clen);
		if (unlikely(err < 0))
			syslog(LOG_ERR, "CPU%u: TCP net write error: %s\n",
			       ws->cpu, strerror(errno));

		count++;
		if (count == 10) {
			err = write_exact(ws->efd[1], &fd, sizeof(fd), 1);
			if (unlikely(err != sizeof(fd)))
				syslog(LOG_ERR, "CPU%u: TCP net put fd back in "
				       "pipe error: %s\n", ws->cpu, strerror(errno));
			return keep;
		}

		errno = 0;
	}

	if (unlikely(rlen < 0 && errno != EAGAIN && errno != EBADF))
		syslog(LOG_ERR, "CPU%u: TCP net read error: %s\n",
		       ws->cpu, strerror(errno));

	return keep;
}