pineapple/externals/libressl/ssl/tls13_legacy.c
2020-12-28 15:15:37 +00:00

525 lines
12 KiB
C
Executable file

/* $OpenBSD: tls13_legacy.c,v 1.13 2020/09/13 15:04:35 jsing Exp $ */
/*
* Copyright (c) 2018, 2019 Joel Sing <jsing@openbsd.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <limits.h>
#include "ssl_locl.h"
#include "tls13_internal.h"
SSL3_ENC_METHOD TLSv1_3_enc_data = {
.enc_flags = SSL_ENC_FLAG_SIGALGS|SSL_ENC_FLAG_TLS1_3_CIPHERS,
};
static ssize_t
tls13_legacy_wire_read(SSL *ssl, uint8_t *buf, size_t len)
{
int n;
if (ssl->rbio == NULL) {
SSLerror(ssl, SSL_R_BIO_NOT_SET);
return TLS13_IO_FAILURE;
}
ssl->internal->rwstate = SSL_READING;
errno = 0;
if ((n = BIO_read(ssl->rbio, buf, len)) <= 0) {
if (BIO_should_read(ssl->rbio))
return TLS13_IO_WANT_POLLIN;
if (BIO_should_write(ssl->rbio))
return TLS13_IO_WANT_POLLOUT;
if (n == 0)
return TLS13_IO_EOF;
if (ERR_peek_error() == 0 && errno != 0)
SYSerror(errno);
return TLS13_IO_FAILURE;
}
if (n == len)
ssl->internal->rwstate = SSL_NOTHING;
return n;
}
ssize_t
tls13_legacy_wire_read_cb(void *buf, size_t n, void *arg)
{
struct tls13_ctx *ctx = arg;
return tls13_legacy_wire_read(ctx->ssl, buf, n);
}
static ssize_t
tls13_legacy_wire_write(SSL *ssl, const uint8_t *buf, size_t len)
{
int n;
if (ssl->wbio == NULL) {
SSLerror(ssl, SSL_R_BIO_NOT_SET);
return TLS13_IO_FAILURE;
}
ssl->internal->rwstate = SSL_WRITING;
errno = 0;
if ((n = BIO_write(ssl->wbio, buf, len)) <= 0) {
if (BIO_should_read(ssl->wbio))
return TLS13_IO_WANT_POLLIN;
if (BIO_should_write(ssl->wbio))
return TLS13_IO_WANT_POLLOUT;
if (ERR_peek_error() == 0 && errno != 0)
SYSerror(errno);
return TLS13_IO_FAILURE;
}
if (n == len)
ssl->internal->rwstate = SSL_NOTHING;
return n;
}
ssize_t
tls13_legacy_wire_write_cb(const void *buf, size_t n, void *arg)
{
struct tls13_ctx *ctx = arg;
return tls13_legacy_wire_write(ctx->ssl, buf, n);
}
static void
tls13_legacy_error(SSL *ssl)
{
struct tls13_ctx *ctx = ssl->internal->tls13;
int reason = SSL_R_UNKNOWN;
/* If we received a fatal alert we already put an error on the stack. */
if (S3I(ssl)->fatal_alert != 0)
return;
switch (ctx->error.code) {
case TLS13_ERR_VERIFY_FAILED:
reason = SSL_R_CERTIFICATE_VERIFY_FAILED;
break;
case TLS13_ERR_HRR_FAILED:
reason = SSL_R_NO_CIPHERS_AVAILABLE;
break;
case TLS13_ERR_TRAILING_DATA:
reason = SSL_R_EXTRA_DATA_IN_MESSAGE;
break;
case TLS13_ERR_NO_SHARED_CIPHER:
reason = SSL_R_NO_SHARED_CIPHER;
break;
case TLS13_ERR_NO_CERTIFICATE:
reason = SSL_R_MISSING_RSA_CERTIFICATE; /* XXX */
break;
case TLS13_ERR_NO_PEER_CERTIFICATE:
reason = SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE;
break;
}
/* Something (probably libcrypto) already pushed an error on the stack. */
if (reason == SSL_R_UNKNOWN && ERR_peek_error() != 0)
return;
ERR_put_error(ERR_LIB_SSL, (0xfff), reason, ctx->error.file,
ctx->error.line);
}
int
tls13_legacy_return_code(SSL *ssl, ssize_t ret)
{
if (ret > INT_MAX) {
SSLerror(ssl, ERR_R_INTERNAL_ERROR);
return -1;
}
/* A successful read, write or other operation. */
if (ret > 0)
return ret;
ssl->internal->rwstate = SSL_NOTHING;
switch (ret) {
case TLS13_IO_EOF:
return 0;
case TLS13_IO_FAILURE:
tls13_legacy_error(ssl);
return -1;
case TLS13_IO_ALERT:
tls13_legacy_error(ssl);
return -1;
case TLS13_IO_WANT_POLLIN:
BIO_set_retry_read(ssl->rbio);
ssl->internal->rwstate = SSL_READING;
return -1;
case TLS13_IO_WANT_POLLOUT:
BIO_set_retry_write(ssl->wbio);
ssl->internal->rwstate = SSL_WRITING;
return -1;
case TLS13_IO_WANT_RETRY:
SSLerror(ssl, ERR_R_INTERNAL_ERROR);
return -1;
}
SSLerror(ssl, ERR_R_INTERNAL_ERROR);
return -1;
}
int
tls13_legacy_pending(const SSL *ssl)
{
struct tls13_ctx *ctx = ssl->internal->tls13;
ssize_t ret;
if (ctx == NULL)
return 0;
ret = tls13_pending_application_data(ctx->rl);
if (ret < 0 || ret > INT_MAX)
return 0;
return ret;
}
int
tls13_legacy_read_bytes(SSL *ssl, int type, unsigned char *buf, int len, int peek)
{
struct tls13_ctx *ctx = ssl->internal->tls13;
ssize_t ret;
if (ctx == NULL || !ctx->handshake_completed) {
if ((ret = ssl->internal->handshake_func(ssl)) <= 0)
return ret;
return tls13_legacy_return_code(ssl, TLS13_IO_WANT_POLLIN);
}
tls13_record_layer_set_retry_after_phh(ctx->rl,
(ctx->ssl->internal->mode & SSL_MODE_AUTO_RETRY) != 0);
if (type != SSL3_RT_APPLICATION_DATA) {
SSLerror(ssl, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return -1;
}
if (len < 0) {
SSLerror(ssl, SSL_R_BAD_LENGTH);
return -1;
}
if (peek)
ret = tls13_peek_application_data(ctx->rl, buf, len);
else
ret = tls13_read_application_data(ctx->rl, buf, len);
return tls13_legacy_return_code(ssl, ret);
}
int
tls13_legacy_write_bytes(SSL *ssl, int type, const void *vbuf, int len)
{
struct tls13_ctx *ctx = ssl->internal->tls13;
const uint8_t *buf = vbuf;
size_t n, sent;
ssize_t ret;
if (ctx == NULL || !ctx->handshake_completed) {
if ((ret = ssl->internal->handshake_func(ssl)) <= 0)
return ret;
return tls13_legacy_return_code(ssl, TLS13_IO_WANT_POLLOUT);
}
if (type != SSL3_RT_APPLICATION_DATA) {
SSLerror(ssl, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
return -1;
}
if (len < 0) {
SSLerror(ssl, SSL_R_BAD_LENGTH);
return -1;
}
/*
* The TLSv1.3 record layer write behaviour is the same as
* SSL_MODE_ENABLE_PARTIAL_WRITE.
*/
if (ssl->internal->mode & SSL_MODE_ENABLE_PARTIAL_WRITE) {
ret = tls13_write_application_data(ctx->rl, buf, len);
return tls13_legacy_return_code(ssl, ret);
}
/*
* In the non-SSL_MODE_ENABLE_PARTIAL_WRITE case we have to loop until
* we have written out all of the requested data.
*/
sent = S3I(ssl)->wnum;
if (len < sent) {
SSLerror(ssl, SSL_R_BAD_LENGTH);
return -1;
}
n = len - sent;
for (;;) {
if (n == 0) {
S3I(ssl)->wnum = 0;
return sent;
}
if ((ret = tls13_write_application_data(ctx->rl,
&buf[sent], n)) <= 0) {
S3I(ssl)->wnum = sent;
return tls13_legacy_return_code(ssl, ret);
}
sent += ret;
n -= ret;
}
}
static int
tls13_use_legacy_stack(struct tls13_ctx *ctx)
{
SSL *s = ctx->ssl;
CBS cbs;
if (!ssl3_setup_init_buffer(s))
return 0;
if (!ssl3_setup_buffers(s))
return 0;
if (!ssl_init_wbio_buffer(s, 1))
return 0;
/* Stash any unprocessed data from the last record. */
tls13_record_layer_rbuf(ctx->rl, &cbs);
if (CBS_len(&cbs) > 0) {
if (!CBS_write_bytes(&cbs,
S3I(s)->rbuf.buf + SSL3_RT_HEADER_LENGTH,
S3I(s)->rbuf.len - SSL3_RT_HEADER_LENGTH, NULL))
return 0;
S3I(s)->rbuf.offset = SSL3_RT_HEADER_LENGTH;
S3I(s)->rbuf.left = CBS_len(&cbs);
S3I(s)->rrec.type = SSL3_RT_HANDSHAKE;
S3I(s)->rrec.length = CBS_len(&cbs);
s->internal->rstate = SSL_ST_READ_BODY;
s->internal->packet = S3I(s)->rbuf.buf;
s->internal->packet_length = SSL3_RT_HEADER_LENGTH;
s->internal->mac_packet = 1;
}
/* Stash the current handshake message. */
tls13_handshake_msg_data(ctx->hs_msg, &cbs);
if (!CBS_write_bytes(&cbs, s->internal->init_buf->data,
s->internal->init_buf->length, NULL))
return 0;
S3I(s)->tmp.reuse_message = 1;
S3I(s)->tmp.message_type = tls13_handshake_msg_type(ctx->hs_msg);
S3I(s)->tmp.message_size = CBS_len(&cbs);
return 1;
}
int
tls13_use_legacy_client(struct tls13_ctx *ctx)
{
SSL *s = ctx->ssl;
s->method = tls_legacy_client_method();
s->internal->handshake_func = s->method->internal->ssl_connect;
s->client_version = s->version = s->method->internal->max_version;
if (!tls13_use_legacy_stack(ctx))
return 0;
S3I(s)->hs.state = SSL3_ST_CR_SRVR_HELLO_A;
return 1;
}
int
tls13_use_legacy_server(struct tls13_ctx *ctx)
{
SSL *s = ctx->ssl;
s->method = tls_legacy_server_method();
s->internal->handshake_func = s->method->internal->ssl_accept;
s->client_version = s->version = s->method->internal->max_version;
s->server = 1;
if (!tls13_use_legacy_stack(ctx))
return 0;
S3I(s)->hs.state = SSL3_ST_SR_CLNT_HELLO_A;
return 1;
}
int
tls13_legacy_accept(SSL *ssl)
{
struct tls13_ctx *ctx = ssl->internal->tls13;
int ret;
if (ctx == NULL) {
if ((ctx = tls13_ctx_new(TLS13_HS_SERVER)) == NULL) {
SSLerror(ssl, ERR_R_INTERNAL_ERROR); /* XXX */
return -1;
}
ssl->internal->tls13 = ctx;
ctx->ssl = ssl;
ctx->hs = &S3I(ssl)->hs_tls13;
if (!tls13_server_init(ctx)) {
if (ERR_peek_error() == 0)
SSLerror(ssl, ERR_R_INTERNAL_ERROR); /* XXX */
return -1;
}
}
ERR_clear_error();
S3I(ssl)->hs.state = SSL_ST_ACCEPT;
ret = tls13_server_accept(ctx);
if (ret == TLS13_IO_USE_LEGACY)
return ssl->method->internal->ssl_accept(ssl);
if (ret == TLS13_IO_SUCCESS)
S3I(ssl)->hs.state = SSL_ST_OK;
return tls13_legacy_return_code(ssl, ret);
}
int
tls13_legacy_connect(SSL *ssl)
{
struct tls13_ctx *ctx = ssl->internal->tls13;
int ret;
#ifdef TLS13_USE_LEGACY_CLIENT_AUTH
/* XXX drop back to legacy for client auth for now */
if (ssl->cert->key->privatekey != NULL) {
ssl->method = tls_legacy_client_method();
return ssl->method->internal->ssl_connect(ssl);
}
#endif
if (ctx == NULL) {
if ((ctx = tls13_ctx_new(TLS13_HS_CLIENT)) == NULL) {
SSLerror(ssl, ERR_R_INTERNAL_ERROR); /* XXX */
return -1;
}
ssl->internal->tls13 = ctx;
ctx->ssl = ssl;
ctx->hs = &S3I(ssl)->hs_tls13;
if (!tls13_client_init(ctx)) {
if (ERR_peek_error() == 0)
SSLerror(ssl, ERR_R_INTERNAL_ERROR); /* XXX */
return -1;
}
}
ERR_clear_error();
S3I(ssl)->hs.state = SSL_ST_CONNECT;
ret = tls13_client_connect(ctx);
if (ret == TLS13_IO_USE_LEGACY)
return ssl->method->internal->ssl_connect(ssl);
if (ret == TLS13_IO_SUCCESS)
S3I(ssl)->hs.state = SSL_ST_OK;
return tls13_legacy_return_code(ssl, ret);
}
int
tls13_legacy_shutdown(SSL *ssl)
{
struct tls13_ctx *ctx = ssl->internal->tls13;
uint8_t buf[512]; /* XXX */
ssize_t ret;
/*
* We need to return 0 when we have sent a close-notify but have not
* yet received one. We return 1 only once we have sent and received
* close-notify alerts. All other cases return -1 and set internal
* state appropriately.
*/
if (ctx == NULL || ssl->internal->quiet_shutdown) {
ssl->internal->shutdown = SSL_SENT_SHUTDOWN | SSL_RECEIVED_SHUTDOWN;
return 1;
}
if (!ctx->close_notify_sent) {
/* Enqueue and send close notify. */
if (!(ssl->internal->shutdown & SSL_SENT_SHUTDOWN)) {
ssl->internal->shutdown |= SSL_SENT_SHUTDOWN;
if ((ret = tls13_send_alert(ctx->rl,
TLS13_ALERT_CLOSE_NOTIFY)) < 0)
return tls13_legacy_return_code(ssl, ret);
}
if ((ret = tls13_record_layer_send_pending(ctx->rl)) !=
TLS13_IO_SUCCESS)
return tls13_legacy_return_code(ssl, ret);
} else if (!ctx->close_notify_recv) {
/*
* If there is no application data pending, attempt to read more
* data in order to receive a close notify. This should trigger
* a record to be read from the wire, which may be application
* handshake or alert data. Only one attempt is made to match
* previous semantics.
*/
if (tls13_pending_application_data(ctx->rl) == 0) {
if ((ret = tls13_read_application_data(ctx->rl, buf,
sizeof(buf))) < 0)
return tls13_legacy_return_code(ssl, ret);
}
}
if (ctx->close_notify_recv)
return 1;
return 0;
}
int
tls13_legacy_servername_process(struct tls13_ctx *ctx, uint8_t *alert)
{
int legacy_alert = SSL_AD_UNRECOGNIZED_NAME;
int ret = SSL_TLSEXT_ERR_NOACK;
SSL_CTX *ssl_ctx = ctx->ssl->ctx;
SSL *ssl = ctx->ssl;
if (ssl_ctx->internal->tlsext_servername_callback == NULL)
ssl_ctx = ssl->initial_ctx;
if (ssl_ctx->internal->tlsext_servername_callback == NULL)
return 1;
ret = ssl_ctx->internal->tlsext_servername_callback(ssl, &legacy_alert,
ssl_ctx->internal->tlsext_servername_arg);
if (ret == SSL_TLSEXT_ERR_ALERT_FATAL ||
ret == SSL_TLSEXT_ERR_ALERT_WARNING) {
if (legacy_alert >= 0 && legacy_alert <= 255)
*alert = legacy_alert;
return 0;
}
return 1;
}