/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2014-2019 Netflix Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_rss.h"
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/domainset.h>
#include <sys/ktls.h>
#include <sys/lock.h>
#include <sys/mbuf.h>
#include <sys/mutex.h>
#include <sys/rmlock.h>
#include <sys/proc.h>
#include <sys/protosw.h>
#include <sys/refcount.h>
#include <sys/smp.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <sys/taskqueue.h>
#include <sys/kthread.h>
#include <sys/uio.h>
#include <sys/vmmeter.h>
#if defined(__aarch64__) || defined(__amd64__) || defined(__i386__)
#include <machine/pcb.h>
#endif
#include <machine/vmparam.h>
#include <net/if.h>
#include <net/if_var.h>
#ifdef RSS
#include <net/netisr.h>
#include <net/rss_config.h>
#endif
#include <net/route.h>
#include <net/route/nhop.h>
#if defined(INET) || defined(INET6)
#include <netinet/in.h>
#include <netinet/in_pcb.h>
#endif
#include <netinet/tcp_var.h>
#ifdef TCP_OFFLOAD
#include <netinet/tcp_offload.h>
#endif
#include <opencrypto/xform.h>
#include <vm/uma_dbg.h>
#include <vm/vm.h>
#include <vm/vm_pageout.h>
#include <vm/vm_page.h>
struct ktls_wq {
struct mtx mtx;
STAILQ_HEAD(, mbuf) m_head;
STAILQ_HEAD(, socket) so_head;
bool running;
} __aligned(CACHE_LINE_SIZE);
struct ktls_domain_info {
int count;
int cpu[MAXCPU];
};
struct ktls_domain_info ktls_domains[MAXMEMDOM];
static struct ktls_wq *ktls_wq;
static struct proc *ktls_proc;
LIST_HEAD(, ktls_crypto_backend) ktls_backends;
static struct rmlock ktls_backends_lock;
static uma_zone_t ktls_session_zone;
static uint16_t ktls_cpuid_lookup[MAXCPU];
SYSCTL_NODE(_kern_ipc, OID_AUTO, tls, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
"Kernel TLS offload");
SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, stats, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
"Kernel TLS offload stats");
static int ktls_allow_unload;
SYSCTL_INT(_kern_ipc_tls, OID_AUTO, allow_unload, CTLFLAG_RDTUN,
&ktls_allow_unload, 0, "Allow software crypto modules to unload");
#ifdef RSS
static int ktls_bind_threads = 1;
#else
static int ktls_bind_threads;
#endif
SYSCTL_INT(_kern_ipc_tls, OID_AUTO, bind_threads, CTLFLAG_RDTUN,
&ktls_bind_threads, 0,
"Bind crypto threads to cores (1) or cores and domains (2) at boot");
static u_int ktls_maxlen = 16384;
SYSCTL_UINT(_kern_ipc_tls, OID_AUTO, maxlen, CTLFLAG_RWTUN,
&ktls_maxlen, 0, "Maximum TLS record size");
static int ktls_number_threads;
SYSCTL_INT(_kern_ipc_tls_stats, OID_AUTO, threads, CTLFLAG_RD,
&ktls_number_threads, 0,
"Number of TLS threads in thread-pool");
static bool ktls_offload_enable;
SYSCTL_BOOL(_kern_ipc_tls, OID_AUTO, enable, CTLFLAG_RWTUN,
&ktls_offload_enable, 0,
"Enable support for kernel TLS offload");
static bool ktls_cbc_enable = true;
SYSCTL_BOOL(_kern_ipc_tls, OID_AUTO, cbc_enable, CTLFLAG_RWTUN,
&ktls_cbc_enable, 1,
"Enable Support of AES-CBC crypto for kernel TLS");
static COUNTER_U64_DEFINE_EARLY(ktls_tasks_active);
SYSCTL_COUNTER_U64(_kern_ipc_tls, OID_AUTO, tasks_active, CTLFLAG_RD,
&ktls_tasks_active, "Number of active tasks");
static COUNTER_U64_DEFINE_EARLY(ktls_cnt_tx_queued);
SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, sw_tx_inqueue, CTLFLAG_RD,
&ktls_cnt_tx_queued,
"Number of TLS records in queue to tasks for SW encryption");
static COUNTER_U64_DEFINE_EARLY(ktls_cnt_rx_queued);
SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, sw_rx_inqueue, CTLFLAG_RD,
&ktls_cnt_rx_queued,
"Number of TLS sockets in queue to tasks for SW decryption");
static COUNTER_U64_DEFINE_EARLY(ktls_offload_total);
SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, offload_total,
CTLFLAG_RD, &ktls_offload_total,
"Total successful TLS setups (parameters set)");
static COUNTER_U64_DEFINE_EARLY(ktls_offload_enable_calls);
SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, enable_calls,
CTLFLAG_RD, &ktls_offload_enable_calls,
"Total number of TLS enable calls made");
static COUNTER_U64_DEFINE_EARLY(ktls_offload_active);
SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, active, CTLFLAG_RD,
&ktls_offload_active, "Total Active TLS sessions");
static COUNTER_U64_DEFINE_EARLY(ktls_offload_corrupted_records);
SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, corrupted_records, CTLFLAG_RD,
&ktls_offload_corrupted_records, "Total corrupted TLS records received");
static COUNTER_U64_DEFINE_EARLY(ktls_offload_failed_crypto);
SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, failed_crypto, CTLFLAG_RD,
&ktls_offload_failed_crypto, "Total TLS crypto failures");
static COUNTER_U64_DEFINE_EARLY(ktls_switch_to_ifnet);
SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, switch_to_ifnet, CTLFLAG_RD,
&ktls_switch_to_ifnet, "TLS sessions switched from SW to ifnet");
static COUNTER_U64_DEFINE_EARLY(ktls_switch_to_sw);
SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, switch_to_sw, CTLFLAG_RD,
&ktls_switch_to_sw, "TLS sessions switched from ifnet to SW");
static COUNTER_U64_DEFINE_EARLY(ktls_switch_failed);
SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, switch_failed, CTLFLAG_RD,
&ktls_switch_failed, "TLS sessions unable to switch between SW and ifnet");
SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, sw, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
"Software TLS session stats");
SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, ifnet, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
"Hardware (ifnet) TLS session stats");
#ifdef TCP_OFFLOAD
SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, toe, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
"TOE TLS session stats");
#endif
static COUNTER_U64_DEFINE_EARLY(ktls_sw_cbc);
SYSCTL_COUNTER_U64(_kern_ipc_tls_sw, OID_AUTO, cbc, CTLFLAG_RD, &ktls_sw_cbc,
"Active number of software TLS sessions using AES-CBC");
static COUNTER_U64_DEFINE_EARLY(ktls_sw_gcm);
SYSCTL_COUNTER_U64(_kern_ipc_tls_sw, OID_AUTO, gcm, CTLFLAG_RD, &ktls_sw_gcm,
"Active number of software TLS sessions using AES-GCM");
static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_cbc);
SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, cbc, CTLFLAG_RD,
&ktls_ifnet_cbc,
"Active number of ifnet TLS sessions using AES-CBC");
static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_gcm);
SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, gcm, CTLFLAG_RD,
&ktls_ifnet_gcm,
"Active number of ifnet TLS sessions using AES-GCM");
static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_reset);
SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, reset, CTLFLAG_RD,
&ktls_ifnet_reset, "TLS sessions updated to a new ifnet send tag");
static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_reset_dropped);
SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, reset_dropped, CTLFLAG_RD,
&ktls_ifnet_reset_dropped,
"TLS sessions dropped after failing to update ifnet send tag");
static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_reset_failed);
SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, reset_failed, CTLFLAG_RD,
&ktls_ifnet_reset_failed,
"TLS sessions that failed to allocate a new ifnet send tag");
static int ktls_ifnet_permitted;
SYSCTL_UINT(_kern_ipc_tls_ifnet, OID_AUTO, permitted, CTLFLAG_RWTUN,
&ktls_ifnet_permitted, 1,
"Whether to permit hardware (ifnet) TLS sessions");
#ifdef TCP_OFFLOAD
static COUNTER_U64_DEFINE_EARLY(ktls_toe_cbc);
SYSCTL_COUNTER_U64(_kern_ipc_tls_toe, OID_AUTO, cbc, CTLFLAG_RD,
&ktls_toe_cbc,
"Active number of TOE TLS sessions using AES-CBC");
static COUNTER_U64_DEFINE_EARLY(ktls_toe_gcm);
SYSCTL_COUNTER_U64(_kern_ipc_tls_toe, OID_AUTO, gcm, CTLFLAG_RD,
&ktls_toe_gcm,
"Active number of TOE TLS sessions using AES-GCM");
#endif
static MALLOC_DEFINE(M_KTLS, "ktls", "Kernel TLS");
static void ktls_cleanup(struct ktls_session *tls);
#if defined(INET) || defined(INET6)
static void ktls_reset_send_tag(void *context, int pending);
#endif
static void ktls_work_thread(void *ctx);
int
ktls_crypto_backend_register(struct ktls_crypto_backend *be)
{
struct ktls_crypto_backend *curr_be, *tmp;
if (be->api_version != KTLS_API_VERSION) {
printf("KTLS: API version mismatch (%d vs %d) for %s\n",
be->api_version, KTLS_API_VERSION,
be->name);
return (EINVAL);
}
rm_wlock(&ktls_backends_lock);
printf("KTLS: Registering crypto method %s with prio %d\n",
be->name, be->prio);
if (LIST_EMPTY(&ktls_backends)) {
LIST_INSERT_HEAD(&ktls_backends, be, next);
} else {
LIST_FOREACH_SAFE(curr_be, &ktls_backends, next, tmp) {
if (curr_be->prio < be->prio) {
LIST_INSERT_BEFORE(curr_be, be, next);
break;
}
if (LIST_NEXT(curr_be, next) == NULL) {
LIST_INSERT_AFTER(curr_be, be, next);
break;
}
}
}
rm_wunlock(&ktls_backends_lock);
return (0);
}
int
ktls_crypto_backend_deregister(struct ktls_crypto_backend *be)
{
struct ktls_crypto_backend *tmp;
/*
* Don't error if the backend isn't registered. This permits
* MOD_UNLOAD handlers to use this function unconditionally.
*/
rm_wlock(&ktls_backends_lock);
LIST_FOREACH(tmp, &ktls_backends, next) {
if (tmp == be)
break;
}
if (tmp == NULL) {
rm_wunlock(&ktls_backends_lock);
return (0);
}
if (!ktls_allow_unload) {
rm_wunlock(&ktls_backends_lock);
printf(
"KTLS: Deregistering crypto method %s is not supported\n",
be->name);
return (EBUSY);
}
if (be->use_count) {
rm_wunlock(&ktls_backends_lock);
return (EBUSY);
}
LIST_REMOVE(be, next);
rm_wunlock(&ktls_backends_lock);
return (0);
}
#if defined(INET) || defined(INET6)
static u_int
ktls_get_cpu(struct socket *so)
{
struct inpcb *inp;
#ifdef NUMA
struct ktls_domain_info *di;
#endif
u_int cpuid;
inp = sotoinpcb(so);
#ifdef RSS
cpuid = rss_hash2cpuid(inp->inp_flowid, inp->inp_flowtype);
if (cpuid != NETISR_CPUID_NONE)
return (cpuid);
#endif
/*
* Just use the flowid to shard connections in a repeatable
* fashion. Note that some crypto backends rely on the
* serialization provided by having the same connection use
* the same queue.
*/
#ifdef NUMA
if (ktls_bind_threads > 1 && inp->inp_numa_domain != M_NODOM) {
di = &ktls_domains[inp->inp_numa_domain];
cpuid = di->cpu[inp->inp_flowid % di->count];
} else
#endif
cpuid = ktls_cpuid_lookup[inp->inp_flowid % ktls_number_threads];
return (cpuid);
}
#endif
static void
ktls_init(void *dummy __unused)
{
struct thread *td;
struct pcpu *pc;
cpuset_t mask;
int count, domain, error, i;
rm_init(&ktls_backends_lock, "ktls backends");
LIST_INIT(&ktls_backends);
ktls_wq = malloc(sizeof(*ktls_wq) * (mp_maxid + 1), M_KTLS,
M_WAITOK | M_ZERO);
ktls_session_zone = uma_zcreate("ktls_session",
sizeof(struct ktls_session),
NULL, NULL, NULL, NULL,
UMA_ALIGN_CACHE, 0);
/*
* Initialize the workqueues to run the TLS work. We create a
* work queue for each CPU.
*/
CPU_FOREACH(i) {
STAILQ_INIT(&ktls_wq[i].m_head);
STAILQ_INIT(&ktls_wq[i].so_head);
mtx_init(&ktls_wq[i].mtx, "ktls work queue", NULL, MTX_DEF);
error = kproc_kthread_add(ktls_work_thread, &ktls_wq[i],
&ktls_proc, &td, 0, 0, "KTLS", "thr_%d", i);
if (error)
panic("Can't add KTLS thread %d error %d", i, error);
/*
* Bind threads to cores. If ktls_bind_threads is >
* 1, then we bind to the NUMA domain.
*/
if (ktls_bind_threads) {
if (ktls_bind_threads > 1) {
pc = pcpu_find(i);
domain = pc->pc_domain;
CPU_COPY(&cpuset_domain[domain], &mask);
count = ktls_domains[domain].count;
ktls_domains[domain].cpu[count] = i;
ktls_domains[domain].count++;
} else {
CPU_SETOF(i, &mask);
}
error = cpuset_setthread(td->td_tid, &mask);
if (error)
panic(
"Unable to bind KTLS thread for CPU %d error %d",
i, error);
}
ktls_cpuid_lookup[ktls_number_threads] = i;
ktls_number_threads++;
}
/*
* If we somehow have an empty domain, fall back to choosing
* among all KTLS threads.
*/
if (ktls_bind_threads > 1) {
for (i = 0; i < vm_ndomains; i++) {
if (ktls_domains[i].count == 0) {
ktls_bind_threads = 1;
break;
}
}
}
printf("KTLS: Initialized %d threads\n", ktls_number_threads);
}
SYSINIT(ktls, SI_SUB_SMP + 1, SI_ORDER_ANY, ktls_init, NULL);
#if defined(INET) || defined(INET6)
static int
ktls_create_session(struct socket *so, struct tls_enable *en,
struct ktls_session **tlsp)
{
struct ktls_session *tls;
int error;
/* Only TLS 1.0 - 1.3 are supported. */
if (en->tls_vmajor != TLS_MAJOR_VER_ONE)
return (EINVAL);
if (en->tls_vminor < TLS_MINOR_VER_ZERO ||
en->tls_vminor > TLS_MINOR_VER_THREE)
return (EINVAL);
if (en->auth_key_len < 0 || en->auth_key_len > TLS_MAX_PARAM_SIZE)
return (EINVAL);
if (en->cipher_key_len < 0 || en->cipher_key_len > TLS_MAX_PARAM_SIZE)
return (EINVAL);
if (en->iv_len < 0 || en->iv_len > sizeof(tls->params.iv))
return (EINVAL);
/* All supported algorithms require a cipher key. */
if (en->cipher_key_len == 0)
return (EINVAL);
/* No flags are currently supported. */
if (en->flags != 0)
return (EINVAL);
/* Common checks for supported algorithms. */
switch (en->cipher_algorithm) {
case CRYPTO_AES_NIST_GCM_16:
/*
* auth_algorithm isn't used, but permit GMAC values
* for compatibility.
*/
switch (en->auth_algorithm) {
case 0:
#ifdef COMPAT_FREEBSD12
/* XXX: Really 13.0-current COMPAT. */
case CRYPTO_AES_128_NIST_GMAC:
case CRYPTO_AES_192_NIST_GMAC:
case CRYPTO_AES_256_NIST_GMAC:
#endif
break;
default:
return (EINVAL);
}
if (en->auth_key_len != 0)
return (EINVAL);
if ((en->tls_vminor == TLS_MINOR_VER_TWO &&
en->iv_len != TLS_AEAD_GCM_LEN) ||
(en->tls_vminor == TLS_MINOR_VER_THREE &&
en->iv_len != TLS_1_3_GCM_IV_LEN))
return (EINVAL);
break;
case CRYPTO_AES_CBC:
switch (en->auth_algorithm) {
case CRYPTO_SHA1_HMAC:
/*
* TLS 1.0 requires an implicit IV. TLS 1.1+
* all use explicit IVs.
*/
if (en->tls_vminor == TLS_MINOR_VER_ZERO) {
if (en->iv_len != TLS_CBC_IMPLICIT_IV_LEN)
return (EINVAL);
break;
}
/* FALLTHROUGH */
case CRYPTO_SHA2_256_HMAC:
case CRYPTO_SHA2_384_HMAC:
/* Ignore any supplied IV. */
en->iv_len = 0;
break;
default:
return (EINVAL);
}
if (en->auth_key_len == 0)
return (EINVAL);
break;
default:
return (EINVAL);
}
tls = uma_zalloc(ktls_session_zone, M_WAITOK | M_ZERO);
counter_u64_add(ktls_offload_active, 1);
refcount_init(&tls->refcount, 1);
TASK_INIT(&tls->reset_tag_task, 0, ktls_reset_send_tag, tls);
tls->wq_index = ktls_get_cpu(so);
tls->params.cipher_algorithm = en->cipher_algorithm;
tls->params.auth_algorithm = en->auth_algorithm;
tls->params.tls_vmajor = en->tls_vmajor;
tls->params.tls_vminor = en->tls_vminor;
tls->params.flags = en->flags;
tls->params.max_frame_len = min(TLS_MAX_MSG_SIZE_V10_2, ktls_maxlen);
/* Set the header and trailer lengths. */
tls->params.tls_hlen = sizeof(struct tls_record_layer);
switch (en->cipher_algorithm) {
case CRYPTO_AES_NIST_GCM_16:
/*
* TLS 1.2 uses a 4 byte implicit IV with an explicit 8 byte
* nonce. TLS 1.3 uses a 12 byte implicit IV.
*/
if (en->tls_vminor < TLS_MINOR_VER_THREE)
tls->params.tls_hlen += sizeof(uint64_t);
tls->params.tls_tlen = AES_GMAC_HASH_LEN;
/*
* TLS 1.3 includes optional padding which we
* do not support, and also puts the "real" record
* type at the end of the encrypted data.
*/
if (en->tls_vminor == TLS_MINOR_VER_THREE)
tls->params.tls_tlen += sizeof(uint8_t);
tls->params.tls_bs = 1;
break;
case CRYPTO_AES_CBC:
switch (en->auth_algorithm) {
case CRYPTO_SHA1_HMAC:
if (en->tls_vminor == TLS_MINOR_VER_ZERO) {
/* Implicit IV, no nonce. */
} else {
tls->params.tls_hlen += AES_BLOCK_LEN;
}
tls->params.tls_tlen = AES_BLOCK_LEN +
SHA1_HASH_LEN;
break;
case CRYPTO_SHA2_256_HMAC:
tls->params.tls_hlen += AES_BLOCK_LEN;
tls->params.tls_tlen = AES_BLOCK_LEN +
SHA2_256_HASH_LEN;
break;
case CRYPTO_SHA2_384_HMAC:
tls->params.tls_hlen += AES_BLOCK_LEN;
tls->params.tls_tlen = AES_BLOCK_LEN +
SHA2_384_HASH_LEN;
break;
default:
panic("invalid hmac");
}
tls->params.tls_bs = AES_BLOCK_LEN;
break;
default:
panic("invalid cipher");
}
KASSERT(tls->params.tls_hlen <= MBUF_PEXT_HDR_LEN,
("TLS header length too long: %d", tls->params.tls_hlen));
KASSERT(tls->params.tls_tlen <= MBUF_PEXT_TRAIL_LEN,
("TLS trailer length too long: %d", tls->params.tls_tlen));
if (en->auth_key_len != 0) {
tls->params.auth_key_len = en->auth_key_len;
tls->params.auth_key = malloc(en->auth_key_len, M_KTLS,
M_WAITOK);
error = copyin(en->auth_key, tls->params.auth_key,
en->auth_key_len);
if (error)
goto out;
}
tls->params.cipher_key_len = en->cipher_key_len;
tls->params.cipher_key = malloc(en->cipher_key_len, M_KTLS, M_WAITOK);
error = copyin(en->cipher_key, tls->params.cipher_key,
en->cipher_key_len);
if (error)
goto out;
/*
* This holds the implicit portion of the nonce for GCM and
* the initial implicit IV for TLS 1.0. The explicit portions
* of the IV are generated in ktls_frame().
*/
if (en->iv_len != 0) {
tls->params.iv_len = en->iv_len;
error = copyin(en->iv, tls->params.iv, en->iv_len);
if (error)
goto out;
/*
* For TLS 1.2, generate an 8-byte nonce as a counter
* to generate unique explicit IVs.
*
* Store this counter in the last 8 bytes of the IV
* array so that it is 8-byte aligned.
*/
if (en->cipher_algorithm == CRYPTO_AES_NIST_GCM_16 &&
en->tls_vminor == TLS_MINOR_VER_TWO)
arc4rand(tls->params.iv + 8, sizeof(uint64_t), 0);
}
*tlsp = tls;
return (0);
out:
ktls_cleanup(tls);
return (error);
}
static struct ktls_session *
ktls_clone_session(struct ktls_session *tls)
{
struct ktls_session *tls_new;
tls_new = uma_zalloc(ktls_session_zone, M_WAITOK | M_ZERO);
counter_u64_add(ktls_offload_active, 1);
refcount_init(&tls_new->refcount, 1);
/* Copy fields from existing session. */
tls_new->params = tls->params;
tls_new->wq_index = tls->wq_index;
/* Deep copy keys. */
if (tls_new->params.auth_key != NULL) {
tls_new->params.auth_key = malloc(tls->params.auth_key_len,
M_KTLS, M_WAITOK);
memcpy(tls_new->params.auth_key, tls->params.auth_key,
tls->params.auth_key_len);
}
tls_new->params.cipher_key = malloc(tls->params.cipher_key_len, M_KTLS,
M_WAITOK);
memcpy(tls_new->params.cipher_key, tls->params.cipher_key,
tls->params.cipher_key_len);
return (tls_new);
}
#endif
static void
ktls_cleanup(struct ktls_session *tls)
{
counter_u64_add(ktls_offload_active, -1);
switch (tls->mode) {
case TCP_TLS_MODE_SW:
MPASS(tls->be != NULL);
switch (tls->params.cipher_algorithm) {
case CRYPTO_AES_CBC:
counter_u64_add(ktls_sw_cbc, -1);
break;
case CRYPTO_AES_NIST_GCM_16:
counter_u64_add(ktls_sw_gcm, -1);
break;
}
tls->free(tls);
break;
case TCP_TLS_MODE_IFNET:
switch (tls->params.cipher_algorithm) {
case CRYPTO_AES_CBC:
counter_u64_add(ktls_ifnet_cbc, -1);
break;
case CRYPTO_AES_NIST_GCM_16:
counter_u64_add(ktls_ifnet_gcm, -1);
break;
}
if (tls->snd_tag != NULL)
m_snd_tag_rele(tls->snd_tag);
break;
#ifdef TCP_OFFLOAD
case TCP_TLS_MODE_TOE:
switch (tls->params.cipher_algorithm) {
case CRYPTO_AES_CBC:
counter_u64_add(ktls_toe_cbc, -1);
break;
case CRYPTO_AES_NIST_GCM_16:
counter_u64_add(ktls_toe_gcm, -1);
break;
}
break;
#endif
}
if (tls->params.auth_key != NULL) {
zfree(tls->params.auth_key, M_KTLS);
tls->params.auth_key = NULL;
tls->params.auth_key_len = 0;
}
if (tls->params.cipher_key != NULL) {
zfree(tls->params.cipher_key, M_KTLS);
tls->params.cipher_key = NULL;
tls->params.cipher_key_len = 0;
}
explicit_bzero(tls->params.iv, sizeof(tls->params.iv));
}
#if defined(INET) || defined(INET6)
#ifdef TCP_OFFLOAD
static int
ktls_try_toe(struct socket *so, struct ktls_session *tls, int direction)
{
struct inpcb *inp;
struct tcpcb *tp;
int error;
inp = so->so_pcb;
INP_WLOCK(inp);
if (inp->inp_flags2 & INP_FREED) {
INP_WUNLOCK(inp);
return (ECONNRESET);
}
if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
INP_WUNLOCK(inp);
return (ECONNRESET);
}
if (inp->inp_socket == NULL) {
INP_WUNLOCK(inp);
return (ECONNRESET);
}
tp = intotcpcb(inp);
if (!(tp->t_flags & TF_TOE)) {
INP_WUNLOCK(inp);
return (EOPNOTSUPP);
}
error = tcp_offload_alloc_tls_session(tp, tls, direction);
INP_WUNLOCK(inp);
if (error == 0) {
tls->mode = TCP_TLS_MODE_TOE;
switch (tls->params.cipher_algorithm) {
case CRYPTO_AES_CBC:
counter_u64_add(ktls_toe_cbc, 1);
break;
case CRYPTO_AES_NIST_GCM_16:
counter_u64_add(ktls_toe_gcm, 1);
break;
}
}
return (error);
}
#endif
/*
* Common code used when first enabling ifnet TLS on a connection or
* when allocating a new ifnet TLS session due to a routing change.
* This function allocates a new TLS send tag on whatever interface
* the connection is currently routed over.
*/
static int
ktls_alloc_snd_tag(struct inpcb *inp, struct ktls_session *tls, bool force,
struct m_snd_tag **mstp)
{
union if_snd_tag_alloc_params params;
struct ifnet *ifp;
struct nhop_object *nh;
struct tcpcb *tp;
int error;
INP_RLOCK(inp);
if (inp->inp_flags2 & INP_FREED) {
INP_RUNLOCK(inp);
return (ECONNRESET);
}
if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
INP_RUNLOCK(inp);
return (ECONNRESET);
}
if (inp->inp_socket == NULL) {
INP_RUNLOCK(inp);
return (ECONNRESET);
}
tp = intotcpcb(inp);
/*
* Check administrative controls on ifnet TLS to determine if
* ifnet TLS should be denied.
*
* - Always permit 'force' requests.
* - ktls_ifnet_permitted == 0: always deny.
*/
if (!force && ktls_ifnet_permitted == 0) {
INP_RUNLOCK(inp);
return (ENXIO);
}
/*
* XXX: Use the cached route in the inpcb to find the
* interface. This should perhaps instead use
* rtalloc1_fib(dst, 0, 0, fibnum). Since KTLS is only
* enabled after a connection has completed key negotiation in
* userland, the cached route will be present in practice.
*/
nh = inp->inp_route.ro_nh;
if (nh == NULL) {
INP_RUNLOCK(inp);
return (ENXIO);
}
ifp = nh->nh_ifp;
if_ref(ifp);
/*
* Allocate a TLS + ratelimit tag if the connection has an
* existing pacing rate.
*/
if (tp->t_pacing_rate != -1 &&
(ifp->if_capenable & IFCAP_TXTLS_RTLMT) != 0) {
params.hdr.type = IF_SND_TAG_TYPE_TLS_RATE_LIMIT;
params.tls_rate_limit.inp = inp;
params.tls_rate_limit.tls = tls;
params.tls_rate_limit.max_rate = tp->t_pacing_rate;
} else {
params.hdr.type = IF_SND_TAG_TYPE_TLS;
params.tls.inp = inp;
params.tls.tls = tls;
}
params.hdr.flowid = inp->inp_flowid;
params.hdr.flowtype = inp->inp_flowtype;
params.hdr.numa_domain = inp->inp_numa_domain;
INP_RUNLOCK(inp);
if ((ifp->if_capenable & IFCAP_MEXTPG) == 0) {
error = EOPNOTSUPP;
goto out;
}
if (inp->inp_vflag & INP_IPV6) {
if ((ifp->if_capenable & IFCAP_TXTLS6) == 0) {
error = EOPNOTSUPP;
goto out;
}
} else {
if ((ifp->if_capenable & IFCAP_TXTLS4) == 0) {
error = EOPNOTSUPP;
goto out;
}
}
error = m_snd_tag_alloc(ifp, ¶ms, mstp);
out:
if_rele(ifp);
return (error);
}
static int
ktls_try_ifnet(struct socket *so, struct ktls_session *tls, bool force)
{
struct m_snd_tag *mst;
int error;
error = ktls_alloc_snd_tag(so->so_pcb, tls, force, &mst);
if (error == 0) {
tls->mode = TCP_TLS_MODE_IFNET;
tls->snd_tag = mst;
switch (tls->params.cipher_algorithm) {
case CRYPTO_AES_CBC:
counter_u64_add(ktls_ifnet_cbc, 1);
break;
case CRYPTO_AES_NIST_GCM_16:
counter_u64_add(ktls_ifnet_gcm, 1);
break;
}
}
return (error);
}
static int
ktls_try_sw(struct socket *so, struct ktls_session *tls, int direction)
{
struct rm_priotracker prio;
struct ktls_crypto_backend *be;
/*
* Choose the best software crypto backend. Backends are
* stored in sorted priority order (larget value == most
* important at the head of the list), so this just stops on
* the first backend that claims the session by returning
* success.
*/
if (ktls_allow_unload)
rm_rlock(&ktls_backends_lock, &prio);
LIST_FOREACH(be, &ktls_backends, next) {
if (be->try(so, tls, direction) == 0)
break;
KASSERT(tls->cipher == NULL,
("ktls backend leaked a cipher pointer"));
}
if (be != NULL) {
if (ktls_allow_unload)
be->use_count++;
tls->be = be;
}
if (ktls_allow_unload)
rm_runlock(&ktls_backends_lock, &prio);
if (be == NULL)
return (EOPNOTSUPP);
tls->mode = TCP_TLS_MODE_SW;
switch (tls->params.cipher_algorithm) {
case CRYPTO_AES_CBC:
counter_u64_add(ktls_sw_cbc, 1);
break;
case CRYPTO_AES_NIST_GCM_16:
counter_u64_add(ktls_sw_gcm, 1);
break;
}
return (0);
}
/*
* KTLS RX stores data in the socket buffer as a list of TLS records,
* where each record is stored as a control message containg the TLS
* header followed by data mbufs containing the decrypted data. This
* is different from KTLS TX which always uses an mb_ext_pgs mbuf for
* both encrypted and decrypted data. TLS records decrypted by a NIC
* should be queued to the socket buffer as records, but encrypted
* data which needs to be decrypted by software arrives as a stream of
* regular mbufs which need to be converted. In addition, there may
* already be pending encrypted data in the socket buffer when KTLS RX
* is enabled.
*
* To manage not-yet-decrypted data for KTLS RX, the following scheme
* is used:
*
* - A single chain of NOTREADY mbufs is hung off of sb_mtls.
*
* - ktls_check_rx checks this chain of mbufs reading the TLS header
* from the first mbuf. Once all of the data for that TLS record is
* queued, the socket is queued to a worker thread.
*
* - The worker thread calls ktls_decrypt to decrypt TLS records in
* the TLS chain. Each TLS record is detached from the TLS chain,
* decrypted, and inserted into the regular socket buffer chain as
* record starting with a control message holding the TLS header and
* a chain of mbufs holding the encrypted data.
*/
static void
sb_mark_notready(struct sockbuf *sb)
{
struct mbuf *m;
m = sb->sb_mb;
sb->sb_mtls = m;
sb->sb_mb = NULL;
sb->sb_mbtail = NULL;
sb->sb_lastrecord = NULL;
for (; m != NULL; m = m->m_next) {
KASSERT(m->m_nextpkt == NULL, ("%s: m_nextpkt != NULL",
__func__));
KASSERT((m->m_flags & M_NOTAVAIL) == 0, ("%s: mbuf not avail",
__func__));
KASSERT(sb->sb_acc >= m->m_len, ("%s: sb_acc < m->m_len",
__func__));
m->m_flags |= M_NOTREADY;
sb->sb_acc -= m->m_len;
sb->sb_tlscc += m->m_len;
sb->sb_mtlstail = m;
}
KASSERT(sb->sb_acc == 0 && sb->sb_tlscc == sb->sb_ccc,
("%s: acc %u tlscc %u ccc %u", __func__, sb->sb_acc, sb->sb_tlscc,
sb->sb_ccc));
}
int
ktls_enable_rx(struct socket *so, struct tls_enable *en)
{
struct ktls_session *tls;
int error;
if (!ktls_offload_enable)
return (ENOTSUP);
if (SOLISTENING(so))
return (EINVAL);
counter_u64_add(ktls_offload_enable_calls, 1);
/*
* This should always be true since only the TCP socket option
* invokes this function.
*/
if (so->so_proto->pr_protocol != IPPROTO_TCP)
return (EINVAL);
/*
* XXX: Don't overwrite existing sessions. We should permit
* this to support rekeying in the future.
*/
if (so->so_rcv.sb_tls_info != NULL)
return (EALREADY);
if (en->cipher_algorithm == CRYPTO_AES_CBC && !ktls_cbc_enable)
return (ENOTSUP);
/* TLS 1.3 is not yet supported. */
if (en->tls_vmajor == TLS_MAJOR_VER_ONE &&
en->tls_vminor == TLS_MINOR_VER_THREE)
return (ENOTSUP);
error = ktls_create_session(so, en, &tls);
if (error)
return (error);
#ifdef TCP_OFFLOAD
error = ktls_try_toe(so, tls, KTLS_RX);
if (error)
#endif
error = ktls_try_sw(so, tls, KTLS_RX);
if (error) {
ktls_cleanup(tls);
return (error);
}
/* Mark the socket as using TLS offload. */
SOCKBUF_LOCK(&so->so_rcv);
so->so_rcv.sb_tls_seqno = be64dec(en->rec_seq);
so->so_rcv.sb_tls_info = tls;
so->so_rcv.sb_flags |= SB_TLS_RX;
/* Mark existing data as not ready until it can be decrypted. */
sb_mark_notready(&so->so_rcv);
ktls_check_rx(&so->so_rcv);
SOCKBUF_UNLOCK(&so->so_rcv);
counter_u64_add(ktls_offload_total, 1);
return (0);
}
int
ktls_enable_tx(struct socket *so, struct tls_enable *en)
{
struct ktls_session *tls;
struct inpcb *inp;
int error;
if (!ktls_offload_enable)
return (ENOTSUP);
if (SOLISTENING(so))
return (EINVAL);
counter_u64_add(ktls_offload_enable_calls, 1);
/*
* This should always be true since only the TCP socket option
* invokes this function.
*/
if (so->so_proto->pr_protocol != IPPROTO_TCP)
return (EINVAL);
/*
* XXX: Don't overwrite existing sessions. We should permit
* this to support rekeying in the future.
*/
if (so->so_snd.sb_tls_info != NULL)
return (EALREADY);
if (en->cipher_algorithm == CRYPTO_AES_CBC && !ktls_cbc_enable)
return (ENOTSUP);
/* TLS requires ext pgs */
if (mb_use_ext_pgs == 0)
return (ENXIO);
error = ktls_create_session(so, en, &tls);
if (error)
return (error);
/* Prefer TOE -> ifnet TLS -> software TLS. */
#ifdef TCP_OFFLOAD
error = ktls_try_toe(so, tls, KTLS_TX);
if (error)
#endif
error = ktls_try_ifnet(so, tls, false);
if (error)
error = ktls_try_sw(so, tls, KTLS_TX);
if (error) {
ktls_cleanup(tls);
return (error);
}
error = sblock(&so->so_snd, SBL_WAIT);
if (error) {
ktls_cleanup(tls);
return (error);
}
/*
* Write lock the INP when setting sb_tls_info so that
* routines in tcp_ratelimit.c can read sb_tls_info while
* holding the INP lock.
*/
inp = so->so_pcb;
INP_WLOCK(inp);
SOCKBUF_LOCK(&so->so_snd);
so->so_snd.sb_tls_seqno = be64dec(en->rec_seq);
so->so_snd.sb_tls_info = tls;
if (tls->mode != TCP_TLS_MODE_SW)
so->so_snd.sb_flags |= SB_TLS_IFNET;
SOCKBUF_UNLOCK(&so->so_snd);
INP_WUNLOCK(inp);
sbunlock(&so->so_snd);
counter_u64_add(ktls_offload_total, 1);
return (0);
}
int
ktls_get_rx_mode(struct socket *so)
{
struct ktls_session *tls;
struct inpcb *inp;
int mode;
if (SOLISTENING(so))
return (EINVAL);
inp = so->so_pcb;
INP_WLOCK_ASSERT(inp);
SOCKBUF_LOCK(&so->so_rcv);
tls = so->so_rcv.sb_tls_info;
if (tls == NULL)
mode = TCP_TLS_MODE_NONE;
else
mode = tls->mode;
SOCKBUF_UNLOCK(&so->so_rcv);
return (mode);
}
int
ktls_get_tx_mode(struct socket *so)
{
struct ktls_session *tls;
struct inpcb *inp;
int mode;
if (SOLISTENING(so))
return (EINVAL);
inp = so->so_pcb;
INP_WLOCK_ASSERT(inp);
SOCKBUF_LOCK(&so->so_snd);
tls = so->so_snd.sb_tls_info;
if (tls == NULL)
mode = TCP_TLS_MODE_NONE;
else
mode = tls->mode;
SOCKBUF_UNLOCK(&so->so_snd);
return (mode);
}
/*
* Switch between SW and ifnet TLS sessions as requested.
*/
int
ktls_set_tx_mode(struct socket *so, int mode)
{
struct ktls_session *tls, *tls_new;
struct inpcb *inp;
int error;
if (SOLISTENING(so))
return (EINVAL);
switch (mode) {
case TCP_TLS_MODE_SW:
case TCP_TLS_MODE_IFNET:
break;
default:
return (EINVAL);
}
inp = so->so_pcb;
INP_WLOCK_ASSERT(inp);
SOCKBUF_LOCK(&so->so_snd);
tls = so->so_snd.sb_tls_info;
if (tls == NULL) {
SOCKBUF_UNLOCK(&so->so_snd);
return (0);
}
if (tls->mode == mode) {
SOCKBUF_UNLOCK(&so->so_snd);
return (0);
}
tls = ktls_hold(tls);
SOCKBUF_UNLOCK(&so->so_snd);
INP_WUNLOCK(inp);
tls_new = ktls_clone_session(tls);
if (mode == TCP_TLS_MODE_IFNET)
error = ktls_try_ifnet(so, tls_new, true);
else
error = ktls_try_sw(so, tls_new, KTLS_TX);
if (error) {
counter_u64_add(ktls_switch_failed, 1);
ktls_free(tls_new);
ktls_free(tls);
INP_WLOCK(inp);
return (error);
}
error = sblock(&so->so_snd, SBL_WAIT);
if (error) {
counter_u64_add(ktls_switch_failed, 1);
ktls_free(tls_new);
ktls_free(tls);
INP_WLOCK(inp);
return (error);
}
/*
* If we raced with another session change, keep the existing
* session.
*/
if (tls != so->so_snd.sb_tls_info) {
counter_u64_add(ktls_switch_failed, 1);
sbunlock(&so->so_snd);
ktls_free(tls_new);
ktls_free(tls);
INP_WLOCK(inp);
return (EBUSY);
}
SOCKBUF_LOCK(&so->so_snd);
so->so_snd.sb_tls_info = tls_new;
if (tls_new->mode != TCP_TLS_MODE_SW)
so->so_snd.sb_flags |= SB_TLS_IFNET;
SOCKBUF_UNLOCK(&so->so_snd);
sbunlock(&so->so_snd);
/*
* Drop two references on 'tls'. The first is for the
* ktls_hold() above. The second drops the reference from the
* socket buffer.
*/
KASSERT(tls->refcount >= 2, ("too few references on old session"));
ktls_free(tls);
ktls_free(tls);
if (mode == TCP_TLS_MODE_IFNET)
counter_u64_add(ktls_switch_to_ifnet, 1);
else
counter_u64_add(ktls_switch_to_sw, 1);
INP_WLOCK(inp);
return (0);
}
/*
* Try to allocate a new TLS send tag. This task is scheduled when
* ip_output detects a route change while trying to transmit a packet
* holding a TLS record. If a new tag is allocated, replace the tag
* in the TLS session. Subsequent packets on the connection will use
* the new tag. If a new tag cannot be allocated, drop the
* connection.
*/
static void
ktls_reset_send_tag(void *context, int pending)
{
struct epoch_tracker et;
struct ktls_session *tls;
struct m_snd_tag *old, *new;
struct inpcb *inp;
struct tcpcb *tp;
int error;
MPASS(pending == 1);
tls = context;
inp = tls->inp;
/*
* Free the old tag first before allocating a new one.
* ip[6]_output_send() will treat a NULL send tag the same as
* an ifp mismatch and drop packets until a new tag is
* allocated.
*
* Write-lock the INP when changing tls->snd_tag since
* ip[6]_output_send() holds a read-lock when reading the
* pointer.
*/
INP_WLOCK(inp);
old = tls->snd_tag;
tls->snd_tag = NULL;
INP_WUNLOCK(inp);
if (old != NULL)
m_snd_tag_rele(old);
error = ktls_alloc_snd_tag(inp, tls, true, &new);
if (error == 0) {
INP_WLOCK(inp);
tls->snd_tag = new;
mtx_pool_lock(mtxpool_sleep, tls);
tls->reset_pending = false;
mtx_pool_unlock(mtxpool_sleep, tls);
if (!in_pcbrele_wlocked(inp))
INP_WUNLOCK(inp);
counter_u64_add(ktls_ifnet_reset, 1);
/*
* XXX: Should we kick tcp_output explicitly now that
* the send tag is fixed or just rely on timers?
*/
} else {
NET_EPOCH_ENTER(et);
INP_WLOCK(inp);
if (!in_pcbrele_wlocked(inp)) {
if (!(inp->inp_flags & INP_TIMEWAIT) &&
!(inp->inp_flags & INP_DROPPED)) {
tp = intotcpcb(inp);
CURVNET_SET(tp->t_vnet);
tp = tcp_drop(tp, ECONNABORTED);
CURVNET_RESTORE();
if (tp != NULL)
INP_WUNLOCK(inp);
counter_u64_add(ktls_ifnet_reset_dropped, 1);
} else
INP_WUNLOCK(inp);
}
NET_EPOCH_EXIT(et);
counter_u64_add(ktls_ifnet_reset_failed, 1);
/*
* Leave reset_pending true to avoid future tasks while
* the socket goes away.
*/
}
ktls_free(tls);
}
int
ktls_output_eagain(struct inpcb *inp, struct ktls_session *tls)
{
if (inp == NULL)
return (ENOBUFS);
INP_LOCK_ASSERT(inp);
/*
* See if we should schedule a task to update the send tag for
* this session.
*/
mtx_pool_lock(mtxpool_sleep, tls);
if (!tls->reset_pending) {
(void) ktls_hold(tls);
in_pcbref(inp);
tls->inp = inp;
tls->reset_pending = true;
taskqueue_enqueue(taskqueue_thread, &tls->reset_tag_task);
}
mtx_pool_unlock(mtxpool_sleep, tls);
return (ENOBUFS);
}
#ifdef RATELIMIT
int
ktls_modify_txrtlmt(struct ktls_session *tls, uint64_t max_pacing_rate)
{
union if_snd_tag_modify_params params = {
.rate_limit.max_rate = max_pacing_rate,
.rate_limit.flags = M_NOWAIT,
};
struct m_snd_tag *mst;
struct ifnet *ifp;
int error;
/* Can't get to the inp, but it should be locked. */
/* INP_LOCK_ASSERT(inp); */
MPASS(tls->mode == TCP_TLS_MODE_IFNET);
if (tls->snd_tag == NULL) {
/*
* Resetting send tag, ignore this change. The
* pending reset may or may not see this updated rate
* in the tcpcb. If it doesn't, we will just lose
* this rate change.
*/
return (0);
}
MPASS(tls->snd_tag != NULL);
MPASS(tls->snd_tag->type == IF_SND_TAG_TYPE_TLS_RATE_LIMIT);
mst = tls->snd_tag;
ifp = mst->ifp;
return (ifp->if_snd_tag_modify(mst, ¶ms));
}
#endif
#endif
void
ktls_destroy(struct ktls_session *tls)
{
struct rm_priotracker prio;
ktls_cleanup(tls);
if (tls->be != NULL && ktls_allow_unload) {
rm_rlock(&ktls_backends_lock, &prio);
tls->be->use_count--;
rm_runlock(&ktls_backends_lock, &prio);
}
uma_zfree(ktls_session_zone, tls);
}
void
ktls_seq(struct sockbuf *sb, struct mbuf *m)
{
for (; m != NULL; m = m->m_next) {
KASSERT((m->m_flags & M_EXTPG) != 0,
("ktls_seq: mapped mbuf %p", m));
m->m_epg_seqno = sb->sb_tls_seqno;
sb->sb_tls_seqno++;
}
}
/*
* Add TLS framing (headers and trailers) to a chain of mbufs. Each
* mbuf in the chain must be an unmapped mbuf. The payload of the
* mbuf must be populated with the payload of each TLS record.
*
* The record_type argument specifies the TLS record type used when
* populating the TLS header.
*
* The enq_count argument on return is set to the number of pages of
* payload data for this entire chain that need to be encrypted via SW
* encryption. The returned value should be passed to ktls_enqueue
* when scheduling encryption of this chain of mbufs. To handle the
* special case of empty fragments for TLS 1.0 sessions, an empty
* fragment counts as one page.
*/
void
ktls_frame(struct mbuf *top, struct ktls_session *tls, int *enq_cnt,
uint8_t record_type)
{
struct tls_record_layer *tlshdr;
struct mbuf *m;
uint64_t *noncep;
uint16_t tls_len;
int maxlen;
maxlen = tls->params.max_frame_len;
*enq_cnt = 0;
for (m = top; m != NULL; m = m->m_next) {
/*
* All mbufs in the chain should be TLS records whose
* payload does not exceed the maximum frame length.
*
* Empty TLS records are permitted when using CBC.
*/
KASSERT(m->m_len <= maxlen &&
(tls->params.cipher_algorithm == CRYPTO_AES_CBC ?
m->m_len >= 0 : m->m_len > 0),
("ktls_frame: m %p len %d\n", m, m->m_len));
/*
* TLS frames require unmapped mbufs to store session
* info.
*/
KASSERT((m->m_flags & M_EXTPG) != 0,
("ktls_frame: mapped mbuf %p (top = %p)\n", m, top));
tls_len = m->m_len;
/* Save a reference to the session. */
m->m_epg_tls = ktls_hold(tls);
m->m_epg_hdrlen = tls->params.tls_hlen;
m->m_epg_trllen = tls->params.tls_tlen;
if (tls->params.cipher_algorithm == CRYPTO_AES_CBC) {
int bs, delta;
/*
* AES-CBC pads messages to a multiple of the
* block size. Note that the padding is
* applied after the digest and the encryption
* is done on the "plaintext || mac || padding".
* At least one byte of padding is always
* present.
*
* Compute the final trailer length assuming
* at most one block of padding.
* tls->params.sb_tls_tlen is the maximum
* possible trailer length (padding + digest).
* delta holds the number of excess padding
* bytes if the maximum were used. Those
* extra bytes are removed.
*/
bs = tls->params.tls_bs;
delta = (tls_len + tls->params.tls_tlen) & (bs - 1);
m->m_epg_trllen -= delta;
}
m->m_len += m->m_epg_hdrlen + m->m_epg_trllen;
/* Populate the TLS header. */
tlshdr = (void *)m->m_epg_hdr;
tlshdr->tls_vmajor = tls->params.tls_vmajor;
/*
* TLS 1.3 masquarades as TLS 1.2 with a record type
* of TLS_RLTYPE_APP.
*/
if (tls->params.tls_vminor == TLS_MINOR_VER_THREE &&
tls->params.tls_vmajor == TLS_MAJOR_VER_ONE) {
tlshdr->tls_vminor = TLS_MINOR_VER_TWO;
tlshdr->tls_type = TLS_RLTYPE_APP;
/* save the real record type for later */
m->m_epg_record_type = record_type;
m->m_epg_trail[0] = record_type;
} else {
tlshdr->tls_vminor = tls->params.tls_vminor;
tlshdr->tls_type = record_type;
}
tlshdr->tls_length = htons(m->m_len - sizeof(*tlshdr));
/*
* Store nonces / explicit IVs after the end of the
* TLS header.
*
* For GCM with TLS 1.2, an 8 byte nonce is copied
* from the end of the IV. The nonce is then
* incremented for use by the next record.
*
* For CBC, a random nonce is inserted for TLS 1.1+.
*/
if (tls->params.cipher_algorithm == CRYPTO_AES_NIST_GCM_16 &&
tls->params.tls_vminor == TLS_MINOR_VER_TWO) {
noncep = (uint64_t *)(tls->params.iv + 8);
be64enc(tlshdr + 1, *noncep);
(*noncep)++;
} else if (tls->params.cipher_algorithm == CRYPTO_AES_CBC &&
tls->params.tls_vminor >= TLS_MINOR_VER_ONE)
arc4rand(tlshdr + 1, AES_BLOCK_LEN, 0);
/*
* When using SW encryption, mark the mbuf not ready.
* It will be marked ready via sbready() after the
* record has been encrypted.
*
* When using ifnet TLS, unencrypted TLS records are
* sent down the stack to the NIC.
*/
if (tls->mode == TCP_TLS_MODE_SW) {
m->m_flags |= M_NOTREADY;
m->m_epg_nrdy = m->m_epg_npgs;
if (__predict_false(tls_len == 0)) {
/* TLS 1.0 empty fragment. */
*enq_cnt += 1;
} else
*enq_cnt += m->m_epg_npgs;
}
}
}
void
ktls_check_rx(struct sockbuf *sb)
{
struct tls_record_layer hdr;
struct ktls_wq *wq;
struct socket *so;
bool running;
SOCKBUF_LOCK_ASSERT(sb);
KASSERT(sb->sb_flags & SB_TLS_RX, ("%s: sockbuf %p isn't TLS RX",
__func__, sb));
so = __containerof(sb, struct socket, so_rcv);
if (sb->sb_flags & SB_TLS_RX_RUNNING)
return;
/* Is there enough queued for a TLS header? */
if (sb->sb_tlscc < sizeof(hdr)) {
if ((sb->sb_state & SBS_CANTRCVMORE) != 0 && sb->sb_tlscc != 0)
so->so_error = EMSGSIZE;
return;
}
m_copydata(sb->sb_mtls, 0, sizeof(hdr), (void *)&hdr);
/* Is the entire record queued? */
if (sb->sb_tlscc < sizeof(hdr) + ntohs(hdr.tls_length)) {
if ((sb->sb_state & SBS_CANTRCVMORE) != 0)
so->so_error = EMSGSIZE;
return;
}
sb->sb_flags |= SB_TLS_RX_RUNNING;
soref(so);
wq = &ktls_wq[so->so_rcv.sb_tls_info->wq_index];
mtx_lock(&wq->mtx);
STAILQ_INSERT_TAIL(&wq->so_head, so, so_ktls_rx_list);
running = wq->running;
mtx_unlock(&wq->mtx);
if (!running)
wakeup(wq);
counter_u64_add(ktls_cnt_rx_queued, 1);
}
static struct mbuf *
ktls_detach_record(struct sockbuf *sb, int len)
{
struct mbuf *m, *n, *top;
int remain;
SOCKBUF_LOCK_ASSERT(sb);
MPASS(len <= sb->sb_tlscc);
/*
* If TLS chain is the exact size of the record,
* just grab the whole record.
*/
top = sb->sb_mtls;
if (sb->sb_tlscc == len) {
sb->sb_mtls = NULL;
sb->sb_mtlstail = NULL;
goto out;
}
/*
* While it would be nice to use m_split() here, we need
* to know exactly what m_split() allocates to update the
* accounting, so do it inline instead.
*/
remain = len;
for (m = top; remain > m->m_len; m = m->m_next)
remain -= m->m_len;
/* Easy case: don't have to split 'm'. */
if (remain == m->m_len) {
sb->sb_mtls = m->m_next;
if (sb->sb_mtls == NULL)
sb->sb_mtlstail = NULL;
m->m_next = NULL;
goto out;
}
/*
* Need to allocate an mbuf to hold the remainder of 'm'. Try
* with M_NOWAIT first.
*/
n = m_get(M_NOWAIT, MT_DATA);
if (n == NULL) {
/*
* Use M_WAITOK with socket buffer unlocked. If
* 'sb_mtls' changes while the lock is dropped, return
* NULL to force the caller to retry.
*/
SOCKBUF_UNLOCK(sb);
n = m_get(M_WAITOK, MT_DATA);
SOCKBUF_LOCK(sb);
if (sb->sb_mtls != top) {
m_free(n);
return (NULL);
}
}
n->m_flags |= M_NOTREADY;
/* Store remainder in 'n'. */
n->m_len = m->m_len - remain;
if (m->m_flags & M_EXT) {
n->m_data = m->m_data + remain;
mb_dupcl(n, m);
} else {
bcopy(mtod(m, caddr_t) + remain, mtod(n, caddr_t), n->m_len);
}
/* Trim 'm' and update accounting. */
m->m_len -= n->m_len;
sb->sb_tlscc -= n->m_len;
sb->sb_ccc -= n->m_len;
/* Account for 'n'. */
sballoc_ktls_rx(sb, n);
/* Insert 'n' into the TLS chain. */
sb->sb_mtls = n;
n->m_next = m->m_next;
if (sb->sb_mtlstail == m)
sb->sb_mtlstail = n;
/* Detach the record from the TLS chain. */
m->m_next = NULL;
out:
MPASS(m_length(top, NULL) == len);
for (m = top; m != NULL; m = m->m_next)
sbfree_ktls_rx(sb, m);
sb->sb_tlsdcc = len;
sb->sb_ccc += len;
SBCHECK(sb);
return (top);
}
static void
ktls_decrypt(struct socket *so)
{
char tls_header[MBUF_PEXT_HDR_LEN];
struct ktls_session *tls;
struct sockbuf *sb;
struct tls_record_layer *hdr;
struct tls_get_record tgr;
struct mbuf *control, *data, *m;
uint64_t seqno;
int error, remain, tls_len, trail_len;
hdr = (struct tls_record_layer *)tls_header;
sb = &so->so_rcv;
SOCKBUF_LOCK(sb);
KASSERT(sb->sb_flags & SB_TLS_RX_RUNNING,
("%s: socket %p not running", __func__, so));
tls = sb->sb_tls_info;
MPASS(tls != NULL);
for (;;) {
/* Is there enough queued for a TLS header? */
if (sb->sb_tlscc < tls->params.tls_hlen)
break;
m_copydata(sb->sb_mtls, 0, tls->params.tls_hlen, tls_header);
tls_len = sizeof(*hdr) + ntohs(hdr->tls_length);
if (hdr->tls_vmajor != tls->params.tls_vmajor ||
hdr->tls_vminor != tls->params.tls_vminor)
error = EINVAL;
else if (tls_len < tls->params.tls_hlen || tls_len >
tls->params.tls_hlen + TLS_MAX_MSG_SIZE_V10_2 +
tls->params.tls_tlen)
error = EMSGSIZE;
else
error = 0;
if (__predict_false(error != 0)) {
/*
* We have a corrupted record and are likely
* out of sync. The connection isn't
* recoverable at this point, so abort it.
*/
SOCKBUF_UNLOCK(sb);
counter_u64_add(ktls_offload_corrupted_records, 1);
CURVNET_SET(so->so_vnet);
so->so_proto->pr_usrreqs->pru_abort(so);
so->so_error = error;
CURVNET_RESTORE();
goto deref;
}
/* Is the entire record queued? */
if (sb->sb_tlscc < tls_len)
break;
/*
* Split out the portion of the mbuf chain containing
* this TLS record.
*/
data = ktls_detach_record(sb, tls_len);
if (data == NULL)
continue;
MPASS(sb->sb_tlsdcc == tls_len);
seqno = sb->sb_tls_seqno;
sb->sb_tls_seqno++;
SBCHECK(sb);
SOCKBUF_UNLOCK(sb);
error = tls->sw_decrypt(tls, hdr, data, seqno, &trail_len);
if (error) {
counter_u64_add(ktls_offload_failed_crypto, 1);
SOCKBUF_LOCK(sb);
if (sb->sb_tlsdcc == 0) {
/*
* sbcut/drop/flush discarded these
* mbufs.
*/
m_freem(data);
break;
}
/*
* Drop this TLS record's data, but keep
* decrypting subsequent records.
*/
sb->sb_ccc -= tls_len;
sb->sb_tlsdcc = 0;
CURVNET_SET(so->so_vnet);
so->so_error = EBADMSG;
sorwakeup_locked(so);
CURVNET_RESTORE();
m_freem(data);
SOCKBUF_LOCK(sb);
continue;
}
/* Allocate the control mbuf. */
tgr.tls_type = hdr->tls_type;
tgr.tls_vmajor = hdr->tls_vmajor;
tgr.tls_vminor = hdr->tls_vminor;
tgr.tls_length = htobe16(tls_len - tls->params.tls_hlen -
trail_len);
control = sbcreatecontrol_how(&tgr, sizeof(tgr),
TLS_GET_RECORD, IPPROTO_TCP, M_WAITOK);
SOCKBUF_LOCK(sb);
if (sb->sb_tlsdcc == 0) {
/* sbcut/drop/flush discarded these mbufs. */
MPASS(sb->sb_tlscc == 0);
m_freem(data);
m_freem(control);
break;
}
/*
* Clear the 'dcc' accounting in preparation for
* adding the decrypted record.
*/
sb->sb_ccc -= tls_len;
sb->sb_tlsdcc = 0;
SBCHECK(sb);
/* If there is no payload, drop all of the data. */
if (tgr.tls_length == htobe16(0)) {
m_freem(data);
data = NULL;
} else {
/* Trim header. */
remain = tls->params.tls_hlen;
while (remain > 0) {
if (data->m_len > remain) {
data->m_data += remain;
data->m_len -= remain;
break;
}
remain -= data->m_len;
data = m_free(data);
}
/* Trim trailer and clear M_NOTREADY. */
remain = be16toh(tgr.tls_length);
m = data;
for (m = data; remain > m->m_len; m = m->m_next) {
m->m_flags &= ~M_NOTREADY;
remain -= m->m_len;
}
m->m_len = remain;
m_freem(m->m_next);
m->m_next = NULL;
m->m_flags &= ~M_NOTREADY;
/* Set EOR on the final mbuf. */
m->m_flags |= M_EOR;
}
sbappendcontrol_locked(sb, data, control, 0);
}
sb->sb_flags &= ~SB_TLS_RX_RUNNING;
if ((sb->sb_state & SBS_CANTRCVMORE) != 0 && sb->sb_tlscc > 0)
so->so_error = EMSGSIZE;
sorwakeup_locked(so);
deref:
SOCKBUF_UNLOCK_ASSERT(sb);
CURVNET_SET(so->so_vnet);
SOCK_LOCK(so);
sorele(so);
CURVNET_RESTORE();
}
void
ktls_enqueue_to_free(struct mbuf *m)
{
struct ktls_wq *wq;
bool running;
/* Mark it for freeing. */
m->m_epg_flags |= EPG_FLAG_2FREE;
wq = &ktls_wq[m->m_epg_tls->wq_index];
mtx_lock(&wq->mtx);
STAILQ_INSERT_TAIL(&wq->m_head, m, m_epg_stailq);
running = wq->running;
mtx_unlock(&wq->mtx);
if (!running)
wakeup(wq);
}
void
ktls_enqueue(struct mbuf *m, struct socket *so, int page_count)
{
struct ktls_wq *wq;
bool running;
KASSERT(((m->m_flags & (M_EXTPG | M_NOTREADY)) ==
(M_EXTPG | M_NOTREADY)),
("ktls_enqueue: %p not unready & nomap mbuf\n", m));
KASSERT(page_count != 0, ("enqueueing TLS mbuf with zero page count"));
KASSERT(m->m_epg_tls->mode == TCP_TLS_MODE_SW, ("!SW TLS mbuf"));
m->m_epg_enc_cnt = page_count;
/*
* Save a pointer to the socket. The caller is responsible
* for taking an additional reference via soref().
*/
m->m_epg_so = so;
wq = &ktls_wq[m->m_epg_tls->wq_index];
mtx_lock(&wq->mtx);
STAILQ_INSERT_TAIL(&wq->m_head, m, m_epg_stailq);
running = wq->running;
mtx_unlock(&wq->mtx);
if (!running)
wakeup(wq);
counter_u64_add(ktls_cnt_tx_queued, 1);
}
static __noinline void
ktls_encrypt(struct mbuf *top)
{
struct ktls_session *tls;
struct socket *so;
struct mbuf *m;
vm_paddr_t parray[1 + btoc(TLS_MAX_MSG_SIZE_V10_2)];
struct iovec src_iov[1 + btoc(TLS_MAX_MSG_SIZE_V10_2)];
struct iovec dst_iov[1 + btoc(TLS_MAX_MSG_SIZE_V10_2)];
vm_page_t pg;
int error, i, len, npages, off, total_pages;
bool is_anon;
so = top->m_epg_so;
tls = top->m_epg_tls;
KASSERT(tls != NULL, ("tls = NULL, top = %p\n", top));
KASSERT(so != NULL, ("so = NULL, top = %p\n", top));
#ifdef INVARIANTS
top->m_epg_so = NULL;
#endif
total_pages = top->m_epg_enc_cnt;
npages = 0;
/*
* Encrypt the TLS records in the chain of mbufs starting with
* 'top'. 'total_pages' gives us a total count of pages and is
* used to know when we have finished encrypting the TLS
* records originally queued with 'top'.
*
* NB: These mbufs are queued in the socket buffer and
* 'm_next' is traversing the mbufs in the socket buffer. The
* socket buffer lock is not held while traversing this chain.
* Since the mbufs are all marked M_NOTREADY their 'm_next'
* pointers should be stable. However, the 'm_next' of the
* last mbuf encrypted is not necessarily NULL. It can point
* to other mbufs appended while 'top' was on the TLS work
* queue.
*
* Each mbuf holds an entire TLS record.
*/
error = 0;
for (m = top; npages != total_pages; m = m->m_next) {
KASSERT(m->m_epg_tls == tls,
("different TLS sessions in a single mbuf chain: %p vs %p",
tls, m->m_epg_tls));
KASSERT((m->m_flags & (M_EXTPG | M_NOTREADY)) ==
(M_EXTPG | M_NOTREADY),
("%p not unready & nomap mbuf (top = %p)\n", m, top));
KASSERT(npages + m->m_epg_npgs <= total_pages,
("page count mismatch: top %p, total_pages %d, m %p", top,
total_pages, m));
/*
* Generate source and destination ivoecs to pass to
* the SW encryption backend. For writable mbufs, the
* destination iovec is a copy of the source and
* encryption is done in place. For file-backed mbufs
* (from sendfile), anonymous wired pages are
* allocated and assigned to the destination iovec.
*/
is_anon = (m->m_epg_flags & EPG_FLAG_ANON) != 0;
off = m->m_epg_1st_off;
for (i = 0; i < m->m_epg_npgs; i++, off = 0) {
len = m_epg_pagelen(m, i, off);
src_iov[i].iov_len = len;
src_iov[i].iov_base =
(char *)(void *)PHYS_TO_DMAP(m->m_epg_pa[i]) +
off;
if (is_anon) {
dst_iov[i].iov_base = src_iov[i].iov_base;
dst_iov[i].iov_len = src_iov[i].iov_len;
continue;
}
retry_page:
pg = vm_page_alloc(NULL, 0, VM_ALLOC_NORMAL |
VM_ALLOC_NOOBJ | VM_ALLOC_NODUMP | VM_ALLOC_WIRED);
if (pg == NULL) {
vm_wait(NULL);
goto retry_page;
}
parray[i] = VM_PAGE_TO_PHYS(pg);
dst_iov[i].iov_base =
(char *)(void *)PHYS_TO_DMAP(parray[i]) + off;
dst_iov[i].iov_len = len;
}
if (__predict_false(m->m_epg_npgs == 0)) {
/* TLS 1.0 empty fragment. */
npages++;
} else
npages += i;
error = (*tls->sw_encrypt)(tls,
(const struct tls_record_layer *)m->m_epg_hdr,
m->m_epg_trail, src_iov, dst_iov, i, m->m_epg_seqno,
m->m_epg_record_type);
if (error) {
counter_u64_add(ktls_offload_failed_crypto, 1);
break;
}
/*
* For file-backed mbufs, release the file-backed
* pages and replace them in the ext_pgs array with
* the anonymous wired pages allocated above.
*/
if (!is_anon) {
/* Free the old pages. */
m->m_ext.ext_free(m);
/* Replace them with the new pages. */
for (i = 0; i < m->m_epg_npgs; i++)
m->m_epg_pa[i] = parray[i];
/* Use the basic free routine. */
m->m_ext.ext_free = mb_free_mext_pgs;
/* Pages are now writable. */
m->m_epg_flags |= EPG_FLAG_ANON;
}
/*
* Drop a reference to the session now that it is no
* longer needed. Existing code depends on encrypted
* records having no associated session vs
* yet-to-be-encrypted records having an associated
* session.
*/
m->m_epg_tls = NULL;
ktls_free(tls);
}
CURVNET_SET(so->so_vnet);
if (error == 0) {
(void)(*so->so_proto->pr_usrreqs->pru_ready)(so, top, npages);
} else {
so->so_proto->pr_usrreqs->pru_abort(so);
so->so_error = EIO;
mb_free_notready(top, total_pages);
}
SOCK_LOCK(so);
sorele(so);
CURVNET_RESTORE();
}
static void
ktls_work_thread(void *ctx)
{
struct ktls_wq *wq = ctx;
struct mbuf *m, *n;
struct socket *so, *son;
STAILQ_HEAD(, mbuf) local_m_head;
STAILQ_HEAD(, socket) local_so_head;
if (ktls_bind_threads > 1) {
curthread->td_domain.dr_policy =
DOMAINSET_PREF(PCPU_GET(domain));
}
#if defined(__aarch64__) || defined(__amd64__) || defined(__i386__)
fpu_kern_thread(0);
#endif
for (;;) {
mtx_lock(&wq->mtx);
while (STAILQ_EMPTY(&wq->m_head) &&
STAILQ_EMPTY(&wq->so_head)) {
wq->running = false;
mtx_sleep(wq, &wq->mtx, 0, "-", 0);
wq->running = true;
}
STAILQ_INIT(&local_m_head);
STAILQ_CONCAT(&local_m_head, &wq->m_head);
STAILQ_INIT(&local_so_head);
STAILQ_CONCAT(&local_so_head, &wq->so_head);
mtx_unlock(&wq->mtx);
STAILQ_FOREACH_SAFE(m, &local_m_head, m_epg_stailq, n) {
if (m->m_epg_flags & EPG_FLAG_2FREE) {
ktls_free(m->m_epg_tls);
uma_zfree(zone_mbuf, m);
} else {
ktls_encrypt(m);
counter_u64_add(ktls_cnt_tx_queued, -1);
}
}
STAILQ_FOREACH_SAFE(so, &local_so_head, so_ktls_rx_list, son) {
ktls_decrypt(so);
counter_u64_add(ktls_cnt_rx_queued, -1);
}
}
}
