ktls.h
/*
* Copyright 2018 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#ifndef OPENSSL_NO_KTLS
# ifndef HEADER_INTERNAL_KTLS
# define HEADER_INTERNAL_KTLS
# if defined(__FreeBSD__)
# include <sys/types.h>
# include <sys/socket.h>
# include <sys/ktls.h>
# include <netinet/in.h>
# include <netinet/tcp.h>
# include <crypto/cryptodev.h>
/*
* Only used by the tests in sslapitest.c.
*/
# define TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE 8
/*
* FreeBSD does not require any additional steps to enable KTLS before
* setting keys.
*/
static ossl_inline int ktls_enable(int fd)
{
return 1;
}
/*
* The TCP_TXTLS_ENABLE socket option marks the outgoing socket buffer
* as using TLS. If successful, then data sent using this socket will
* be encrypted and encapsulated in TLS records using the tls_en.
* provided here.
*/
static ossl_inline int ktls_start(int fd,
struct tls_enable *tls_en,
size_t len, int is_tx)
{
if (is_tx)
return setsockopt(fd, IPPROTO_TCP, TCP_TXTLS_ENABLE,
tls_en, sizeof(*tls_en)) ? 0 : 1;
else
return 0;
}
/*
* Send a TLS record using the tls_en provided in ktls_start and use
* record_type instead of the default SSL3_RT_APPLICATION_DATA.
* When the socket is non-blocking, then this call either returns EAGAIN or
* the entire record is pushed to TCP. It is impossible to send a partial
* record using this control message.
*/
static ossl_inline int ktls_send_ctrl_message(int fd, unsigned char record_type,
const void *data, size_t length)
{
struct msghdr msg = { 0 };
int cmsg_len = sizeof(record_type);
struct cmsghdr *cmsg;
char buf[CMSG_SPACE(cmsg_len)];
struct iovec msg_iov; /* Vector of data to send/receive into */
msg.msg_control = buf;
msg.msg_controllen = sizeof(buf);
cmsg = CMSG_FIRSTHDR(&msg);
cmsg->cmsg_level = IPPROTO_TCP;
cmsg->cmsg_type = TLS_SET_RECORD_TYPE;
cmsg->cmsg_len = CMSG_LEN(cmsg_len);
*((unsigned char *)CMSG_DATA(cmsg)) = record_type;
msg.msg_controllen = cmsg->cmsg_len;
msg_iov.iov_base = (void *)data;
msg_iov.iov_len = length;
msg.msg_iov = &msg_iov;
msg.msg_iovlen = 1;
return sendmsg(fd, &msg, 0);
}
static ossl_inline int ktls_read_record(int fd, void *data, size_t length)
{
return -1;
}
/*
* KTLS enables the sendfile system call to send data from a file over
* TLS.
*/
static ossl_inline ossl_ssize_t ktls_sendfile(int s, int fd, off_t off,
size_t size, int flags)
{
off_t sbytes;
int ret;
ret = sendfile(fd, s, off, size, NULL, &sbytes, flags);
if (ret == -1) {
if (errno == EAGAIN && sbytes != 0)
return sbytes;
return -1;
}
return sbytes;
}
# endif /* __FreeBSD__ */
# if defined(OPENSSL_SYS_LINUX)
# include <linux/version.h>
# define K_MAJ 4
# define K_MIN1 13
# define K_MIN2 0
# if LINUX_VERSION_CODE < KERNEL_VERSION(K_MAJ, K_MIN1, K_MIN2)
# ifndef PEDANTIC
# warning "KTLS requires Kernel Headers >= 4.13.0"
# warning "Skipping Compilation of KTLS"
# endif
# define TLS_TX 1
# define TLS_RX 2
# define TLS_CIPHER_AES_GCM_128 51
# define TLS_CIPHER_AES_GCM_128_IV_SIZE 8
# define TLS_CIPHER_AES_GCM_128_KEY_SIZE 16
# define TLS_CIPHER_AES_GCM_128_SALT_SIZE 4
# define TLS_CIPHER_AES_GCM_128_TAG_SIZE 16
# define TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE 8
# define TLS_SET_RECORD_TYPE 1
struct tls_crypto_info {
unsigned short version;
unsigned short cipher_type;
};
struct tls12_crypto_info_aes_gcm_128 {
struct tls_crypto_info info;
unsigned char iv[TLS_CIPHER_AES_GCM_128_IV_SIZE];
unsigned char key[TLS_CIPHER_AES_GCM_128_KEY_SIZE];
unsigned char salt[TLS_CIPHER_AES_GCM_128_SALT_SIZE];
unsigned char rec_seq[TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE];
};
/* Dummy functions here */
static ossl_inline int ktls_enable(int fd)
{
return 0;
}
static ossl_inline int ktls_start(int fd,
struct tls12_crypto_info_aes_gcm_128
*crypto_info, size_t len, int is_tx)
{
return 0;
}
static ossl_inline int ktls_send_ctrl_message(int fd, unsigned char record_type,
const void *data, size_t length)
{
return -1;
}
static ossl_inline int ktls_read_record(int fd, void *data, size_t length)
{
return -1;
}
static ossl_inline ossl_ssize_t ktls_sendfile(int s, int fd, off_t off, size_t size, int flags)
{
return -1;
}
# else /* KERNEL_VERSION */
# include <sys/sendfile.h>
# include <netinet/tcp.h>
# include <linux/tls.h>
# include <linux/socket.h>
# include "openssl/ssl3.h"
# include "openssl/tls1.h"
# include "openssl/evp.h"
# ifndef SOL_TLS
# define SOL_TLS 282
# endif
# ifndef TCP_ULP
# define TCP_ULP 31
# endif
# ifndef TLS_RX
# define TLS_RX 2
# endif
/*
* When successful, this socket option doesn't change the behaviour of the
* TCP socket, except changing the TCP setsockopt handler to enable the
* processing of SOL_TLS socket options. All other functionality remains the
* same.
*/
static ossl_inline int ktls_enable(int fd)
{
return setsockopt(fd, SOL_TCP, TCP_ULP, "tls", sizeof("tls")) ? 0 : 1;
}
/*
* The TLS_TX socket option changes the send/sendmsg handlers of the TCP socket.
* If successful, then data sent using this socket will be encrypted and
* encapsulated in TLS records using the crypto_info provided here.
* The TLS_RX socket option changes the recv/recvmsg handlers of the TCP socket.
* If successful, then data received using this socket will be decrypted,
* authenticated and decapsulated using the crypto_info provided here.
*/
static ossl_inline int ktls_start(int fd,
struct tls12_crypto_info_aes_gcm_128
*crypto_info, size_t len, int is_tx)
{
return setsockopt(fd, SOL_TLS, is_tx ? TLS_TX : TLS_RX,
crypto_info, sizeof(*crypto_info)) ? 0 : 1;
}
/*
* Send a TLS record using the crypto_info provided in ktls_start and use
* record_type instead of the default SSL3_RT_APPLICATION_DATA.
* When the socket is non-blocking, then this call either returns EAGAIN or
* the entire record is pushed to TCP. It is impossible to send a partial
* record using this control message.
*/
static ossl_inline int ktls_send_ctrl_message(int fd, unsigned char record_type,
const void *data, size_t length)
{
struct msghdr msg;
int cmsg_len = sizeof(record_type);
struct cmsghdr *cmsg;
union {
struct cmsghdr hdr;
char buf[CMSG_SPACE(sizeof(unsigned char))];
} cmsgbuf;
struct iovec msg_iov; /* Vector of data to send/receive into */
memset(&msg, 0, sizeof(msg));
msg.msg_control = cmsgbuf.buf;
msg.msg_controllen = sizeof(cmsgbuf.buf);
cmsg = CMSG_FIRSTHDR(&msg);
cmsg->cmsg_level = SOL_TLS;
cmsg->cmsg_type = TLS_SET_RECORD_TYPE;
cmsg->cmsg_len = CMSG_LEN(cmsg_len);
*((unsigned char *)CMSG_DATA(cmsg)) = record_type;
msg.msg_controllen = cmsg->cmsg_len;
msg_iov.iov_base = (void *)data;
msg_iov.iov_len = length;
msg.msg_iov = &msg_iov;
msg.msg_iovlen = 1;
return sendmsg(fd, &msg, 0);
}
/*
* KTLS enables the sendfile system call to send data from a file over TLS.
* @flags are ignored on Linux. (placeholder for FreeBSD sendfile)
* */
static ossl_inline ossl_ssize_t ktls_sendfile(int s, int fd, off_t off, size_t size, int flags)
{
return sendfile(s, fd, &off, size);
}
# define K_MIN1_RX 17
# if LINUX_VERSION_CODE < KERNEL_VERSION(K_MAJ, K_MIN1_RX, K_MIN2)
# ifndef PEDANTIC
# warning "KTLS requires Kernel Headers >= 4.17.0 for receiving"
# warning "Skipping Compilation of KTLS receive data path"
# endif
static ossl_inline int ktls_read_record(int fd, void *data, size_t length)
{
return -1;
}
# else
/*
* Receive a TLS record using the crypto_info provided in ktls_start.
* The kernel strips the TLS record header, IV and authentication tag,
* returning only the plaintext data or an error on failure.
* We add the TLS record header here to satisfy routines in rec_layer_s3.c
*/
static ossl_inline int ktls_read_record(int fd, void *data, size_t length)
{
struct msghdr msg;
struct cmsghdr *cmsg;
union {
struct cmsghdr hdr;
char buf[CMSG_SPACE(sizeof(unsigned char))];
} cmsgbuf;
struct iovec msg_iov;
int ret;
unsigned char *p = data;
const size_t prepend_length = SSL3_RT_HEADER_LENGTH;
if (length < prepend_length + EVP_GCM_TLS_TAG_LEN) {
errno = EINVAL;
return -1;
}
memset(&msg, 0, sizeof(msg));
msg.msg_control = cmsgbuf.buf;
msg.msg_controllen = sizeof(cmsgbuf.buf);
msg_iov.iov_base = p + prepend_length;
msg_iov.iov_len = length - prepend_length - EVP_GCM_TLS_TAG_LEN;
msg.msg_iov = &msg_iov;
msg.msg_iovlen = 1;
ret = recvmsg(fd, &msg, 0);
if (ret < 0)
return ret;
if (msg.msg_controllen > 0) {
cmsg = CMSG_FIRSTHDR(&msg);
if (cmsg->cmsg_type == TLS_GET_RECORD_TYPE) {
p[0] = *((unsigned char *)CMSG_DATA(cmsg));
p[1] = TLS1_2_VERSION_MAJOR;
p[2] = TLS1_2_VERSION_MINOR;
/* returned length is limited to msg_iov.iov_len above */
p[3] = (ret >> 8) & 0xff;
p[4] = ret & 0xff;
ret += prepend_length;
}
}
return ret;
}
# endif
# endif
# endif
# endif
#endif
