1
0
mirror of https://github.com/moparisthebest/curl synced 2024-11-04 16:45:06 -05:00
curl/lib/vtls/rustls.c
Daniel Stenberg cfff12a0b3
lib: remove 'conn->data' completely
The Curl_easy pointer struct entry in connectdata is now gone. Just
before commit 215db086e0 landed on January 8, 2021 there were 919
references to conn->data.

Closes #6608
2021-02-16 10:48:57 +01:00

496 lines
16 KiB
C

/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 2020 - 2021, Jacob Hoffman-Andrews,
* <github@hoffman-andrews.com>
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
***************************************************************************/
#include "curl_setup.h"
#ifdef USE_RUSTLS
#include "curl_printf.h"
#include <errno.h>
#include <crustls.h>
#include "urldata.h"
#include "sendf.h"
#include "vtls.h"
#include "select.h"
#include "multiif.h"
struct ssl_backend_data
{
const struct rustls_client_config *config;
struct rustls_client_session *session;
bool data_pending;
};
/* For a given rustls_result error code, return the best-matching CURLcode. */
static CURLcode map_error(rustls_result r)
{
if(rustls_result_is_cert_error(r)) {
return CURLE_PEER_FAILED_VERIFICATION;
}
switch(r) {
case RUSTLS_RESULT_OK:
return CURLE_OK;
case RUSTLS_RESULT_NULL_PARAMETER:
return CURLE_BAD_FUNCTION_ARGUMENT;
default:
return CURLE_READ_ERROR;
}
}
static bool
cr_data_pending(const struct connectdata *conn, int sockindex)
{
const struct ssl_connect_data *connssl = &conn->ssl[sockindex];
struct ssl_backend_data *backend = connssl->backend;
return backend->data_pending;
}
static CURLcode
cr_connect(struct Curl_easy *data UNUSED_PARAM,
struct connectdata *conn UNUSED_PARAM,
int sockindex UNUSED_PARAM)
{
infof(data, "rustls_connect: unimplemented\n");
return CURLE_SSL_CONNECT_ERROR;
}
/*
* On each run:
* - Read a chunk of bytes from the socket into rustls' TLS input buffer.
* - Tell rustls to process any new packets.
* - Read out as many plaintext bytes from rustls as possible, until hitting
* error, EOF, or EAGAIN/EWOULDBLOCK, or plainbuf/plainlen is filled up.
*
* It's okay to call this function with plainbuf == NULL and plainlen == 0.
* In that case, it will copy bytes from the socket into rustls' TLS input
* buffer, and process packets, but won't consume bytes from rustls' plaintext
* output buffer.
*/
static ssize_t
cr_recv(struct Curl_easy *data, int sockindex,
char *plainbuf, size_t plainlen, CURLcode *err)
{
struct connectdata *conn = data->conn;
struct ssl_connect_data *const connssl = &conn->ssl[sockindex];
struct ssl_backend_data *const backend = connssl->backend;
struct rustls_client_session *const session = backend->session;
curl_socket_t sockfd = conn->sock[sockindex];
/* Per https://www.bearssl.org/api1.html, max TLS record size plus max
per-record overhead. */
uint8_t tlsbuf[16384 + 325];
size_t n = 0;
ssize_t tls_bytes_read = 0;
size_t tls_bytes_processed = 0;
size_t plain_bytes_copied = 0;
rustls_result rresult = 0;
char errorbuf[255];
tls_bytes_read = sread(sockfd, tlsbuf, sizeof(tlsbuf));
if(tls_bytes_read == 0) {
failf(data, "EOF in sread");
*err = CURLE_READ_ERROR;
return -1;
}
else if(tls_bytes_read < 0) {
if(SOCKERRNO == EAGAIN || SOCKERRNO == EWOULDBLOCK) {
infof(data, "sread: EAGAIN or EWOULDBLOCK\n");
*err = CURLE_AGAIN;
return -1;
}
failf(data, "reading from socket: %s", strerror(SOCKERRNO));
*err = CURLE_READ_ERROR;
return -1;
}
/*
* Now pull those bytes from the buffer into ClientSession.
*/
DEBUGASSERT(tls_bytes_read > 0);
while(tls_bytes_processed < (size_t)tls_bytes_read) {
rresult = rustls_client_session_read_tls(session,
(uint8_t *)tlsbuf + tls_bytes_processed,
tls_bytes_read - tls_bytes_processed,
&n);
if(rresult != RUSTLS_RESULT_OK) {
failf(data, "error in rustls_client_session_read_tls");
*err = CURLE_READ_ERROR;
return -1;
}
else if(n == 0) {
infof(data, "EOF from rustls_client_session_read_tls\n");
break;
}
rresult = rustls_client_session_process_new_packets(session);
if(rresult != RUSTLS_RESULT_OK) {
rustls_error(rresult, errorbuf, sizeof(errorbuf), &n);
failf(data, "%.*s", n, errorbuf);
*err = map_error(rresult);
return -1;
}
tls_bytes_processed += n;
backend->data_pending = TRUE;
}
while(plain_bytes_copied < plainlen) {
rresult = rustls_client_session_read(session,
(uint8_t *)plainbuf + plain_bytes_copied,
plainlen - plain_bytes_copied,
&n);
if(rresult != RUSTLS_RESULT_OK) {
failf(data, "error in rustls_client_session_read");
*err = CURLE_READ_ERROR;
return -1;
}
else if(n == 0) {
/* rustls returns 0 from client_session_read to mean "all currently
available data has been read." If we bring in more ciphertext with
read_tls, more plaintext will become available. So don't tell curl
this is an EOF. Instead, say "come back later." */
infof(data, "EOF from rustls_client_session_read\n");
backend->data_pending = FALSE;
break;
}
else {
plain_bytes_copied += n;
}
}
/* If we wrote out 0 plaintext bytes, it might just mean we haven't yet
read a full TLS record. Return CURLE_AGAIN so curl doesn't treat this
as EOF. */
if(plain_bytes_copied == 0) {
*err = CURLE_AGAIN;
return -1;
}
return plain_bytes_copied;
}
/*
* On each call:
* - Copy `plainlen` bytes into rustls' plaintext input buffer (if > 0).
* - Fully drain rustls' plaintext output buffer into the socket until
* we get either an error or EAGAIN/EWOULDBLOCK.
*
* It's okay to call this function with plainbuf == NULL and plainlen == 0.
* In that case, it won't read anything into rustls' plaintext input buffer.
* It will only drain rustls' plaintext output buffer into the socket.
*/
static ssize_t
cr_send(struct Curl_easy *data, int sockindex,
const void *plainbuf, size_t plainlen, CURLcode *err)
{
struct connectdata *conn = data->conn;
struct ssl_connect_data *const connssl = &conn->ssl[sockindex];
struct ssl_backend_data *const backend = connssl->backend;
struct rustls_client_session *const session = backend->session;
curl_socket_t sockfd = conn->sock[sockindex];
ssize_t n = 0;
size_t plainwritten = 0;
size_t tlslen = 0;
size_t tlswritten = 0;
/* Max size of a TLS message, plus some space for TLS framing overhead. */
uint8_t tlsbuf[16384 + 325];
rustls_result rresult;
if(plainlen > 0) {
rresult = rustls_client_session_write(session,
plainbuf, plainlen, &plainwritten);
if(rresult != RUSTLS_RESULT_OK) {
failf(data, "error in rustls_client_session_write");
*err = CURLE_WRITE_ERROR;
return -1;
}
else if(plainwritten == 0) {
failf(data, "EOF in rustls_client_session_write");
*err = CURLE_WRITE_ERROR;
return -1;
}
}
while(rustls_client_session_wants_write(session)) {
rresult = rustls_client_session_write_tls(
session, tlsbuf, sizeof(tlsbuf), &tlslen);
if(rresult != RUSTLS_RESULT_OK) {
failf(data, "error in rustls_client_session_write_tls");
*err = CURLE_WRITE_ERROR;
return -1;
}
else if(tlslen == 0) {
failf(data, "EOF in rustls_client_session_write_tls");
*err = CURLE_WRITE_ERROR;
return -1;
}
tlswritten = 0;
while(tlswritten < tlslen) {
n = swrite(sockfd, tlsbuf + tlswritten, tlslen - tlswritten);
if(n < 0) {
if(SOCKERRNO == EAGAIN || SOCKERRNO == EWOULDBLOCK) {
/* Since recv is called from poll, there should be room to
write at least some bytes before hitting EAGAIN. */
infof(data, "swrite: EAGAIN after %ld bytes\n", tlswritten);
DEBUGASSERT(tlswritten > 0);
break;
}
failf(data, "error in swrite");
*err = CURLE_WRITE_ERROR;
return -1;
}
if(n == 0) {
failf(data, "EOF in swrite");
*err = CURLE_WRITE_ERROR;
return -1;
}
tlswritten += n;
}
DEBUGASSERT(tlswritten <= tlslen);
}
return plainwritten;
}
static CURLcode
cr_connect_nonblocking(struct Curl_easy *data, struct connectdata *conn,
int sockindex, bool *done)
{
struct ssl_connect_data *const connssl = &conn->ssl[sockindex];
curl_socket_t sockfd = conn->sock[sockindex];
struct ssl_backend_data *const backend = connssl->backend;
struct rustls_client_session *session = backend->session;
struct rustls_client_config_builder *config_builder = NULL;
const char *const ssl_cafile = SSL_CONN_CONFIG(CAfile);
CURLcode tmperr = CURLE_OK;
int result;
int what;
bool wants_read;
bool wants_write;
curl_socket_t writefd;
curl_socket_t readfd;
char errorbuf[256];
size_t errorlen;
if(ssl_connection_none == connssl->state) {
config_builder = rustls_client_config_builder_new();
if(ssl_cafile) {
result = rustls_client_config_builder_load_roots_from_file(
config_builder, ssl_cafile);
if(result != RUSTLS_RESULT_OK) {
failf(data, "failed to load trusted certificates");
rustls_client_config_free(
rustls_client_config_builder_build(config_builder));
return CURLE_SSL_CACERT_BADFILE;
}
}
else {
result = rustls_client_config_builder_load_native_roots(config_builder);
if(result != RUSTLS_RESULT_OK) {
failf(data, "failed to load trusted certificates");
rustls_client_config_free(
rustls_client_config_builder_build(config_builder));
return CURLE_SSL_CACERT_BADFILE;
}
}
backend->config = rustls_client_config_builder_build(config_builder);
DEBUGASSERT(session == NULL);
result = rustls_client_session_new(
backend->config, conn->host.name, &session);
if(result != RUSTLS_RESULT_OK) {
rustls_error(result, errorbuf, sizeof(errorbuf), &errorlen);
failf(data, "failed to create client session: %.*s", errorlen, errorbuf);
return CURLE_COULDNT_CONNECT;
}
backend->session = session;
connssl->state = ssl_connection_negotiating;
}
/* Read/write data until the handshake is done or the socket would block. */
for(;;) {
/*
* Connection has been established according to rustls. Set send/recv
* handlers, and update the state machine.
* This check has to come last because is_handshaking starts out false,
* then becomes true when we first write data, then becomes false again
* once the handshake is done.
*/
if(!rustls_client_session_is_handshaking(session)) {
infof(data, "Done handshaking\n");
/* Done with the handshake. Set up callbacks to send/receive data. */
connssl->state = ssl_connection_complete;
conn->recv[sockindex] = cr_recv;
conn->send[sockindex] = cr_send;
*done = TRUE;
return CURLE_OK;
}
wants_read = rustls_client_session_wants_read(session);
wants_write = rustls_client_session_wants_write(session);
DEBUGASSERT(wants_read || wants_write);
writefd = wants_write?sockfd:CURL_SOCKET_BAD;
readfd = wants_read?sockfd:CURL_SOCKET_BAD;
what = Curl_socket_check(readfd, CURL_SOCKET_BAD, writefd, 0);
if(what < 0) {
/* fatal error */
failf(data, "select/poll on SSL socket, errno: %d", SOCKERRNO);
return CURLE_SSL_CONNECT_ERROR;
}
if(0 == what) {
infof(data, "Curl_socket_check: %s would block\n",
wants_read&&wants_write ?
"writing and reading" :
wants_write ?
"writing" :
"reading");
*done = FALSE;
return CURLE_OK;
}
/* socket is readable or writable */
if(wants_write) {
infof(data, "ClientSession wants us to write_tls.\n");
cr_send(data, sockindex, NULL, 0, &tmperr);
if(tmperr == CURLE_AGAIN) {
infof(data, "writing would block\n");
/* fall through */
}
else if(tmperr != CURLE_OK) {
return tmperr;
}
}
if(wants_read) {
infof(data, "ClientSession wants us to read_tls.\n");
cr_recv(data, sockindex, NULL, 0, &tmperr);
if(tmperr == CURLE_AGAIN) {
infof(data, "reading would block\n");
/* fall through */
}
else if(tmperr != CURLE_OK) {
if(tmperr == CURLE_READ_ERROR) {
return CURLE_SSL_CONNECT_ERROR;
}
else {
return tmperr;
}
}
}
}
/* We should never fall through the loop. We should return either because
the handshake is done or because we can't read/write without blocking. */
DEBUGASSERT(false);
}
/* returns a bitmap of flags for this connection's first socket indicating
whether we want to read or write */
static int
cr_getsock(struct connectdata *conn, curl_socket_t *socks)
{
struct ssl_connect_data *const connssl = &conn->ssl[FIRSTSOCKET];
curl_socket_t sockfd = conn->sock[FIRSTSOCKET];
struct ssl_backend_data *const backend = connssl->backend;
struct rustls_client_session *session = backend->session;
if(rustls_client_session_wants_write(session)) {
socks[0] = sockfd;
return GETSOCK_WRITESOCK(0);
}
if(rustls_client_session_wants_read(session)) {
socks[0] = sockfd;
return GETSOCK_READSOCK(0);
}
return GETSOCK_BLANK;
}
static void *
cr_get_internals(struct ssl_connect_data *connssl,
CURLINFO info UNUSED_PARAM)
{
struct ssl_backend_data *backend = connssl->backend;
return &backend->session;
}
static void
cr_close(struct Curl_easy *data, struct connectdata *conn,
int sockindex)
{
struct ssl_connect_data *connssl = &conn->ssl[sockindex];
struct ssl_backend_data *backend = connssl->backend;
CURLcode tmperr = CURLE_OK;
ssize_t n = 0;
if(backend->session) {
rustls_client_session_send_close_notify(backend->session);
n = cr_send(data, sockindex, NULL, 0, &tmperr);
if(n < 0) {
failf(data, "error sending close notify: %d", tmperr);
}
rustls_client_session_free(backend->session);
backend->session = NULL;
}
if(backend->config) {
rustls_client_config_free(backend->config);
backend->config = NULL;
}
}
const struct Curl_ssl Curl_ssl_rustls = {
{ CURLSSLBACKEND_RUSTLS, "rustls" },
SSLSUPP_TLS13_CIPHERSUITES, /* supports */
sizeof(struct ssl_backend_data),
Curl_none_init, /* init */
Curl_none_cleanup, /* cleanup */
rustls_version, /* version */
Curl_none_check_cxn, /* check_cxn */
Curl_none_shutdown, /* shutdown */
cr_data_pending, /* data_pending */
Curl_none_random, /* random */
Curl_none_cert_status_request, /* cert_status_request */
cr_connect, /* connect */
cr_connect_nonblocking, /* connect_nonblocking */
cr_getsock, /* cr_getsock */
cr_get_internals, /* get_internals */
cr_close, /* close_one */
Curl_none_close_all, /* close_all */
Curl_none_session_free, /* session_free */
Curl_none_set_engine, /* set_engine */
Curl_none_set_engine_default, /* set_engine_default */
Curl_none_engines_list, /* engines_list */
Curl_none_false_start, /* false_start */
NULL /* sha256sum */
};
#endif /* USE_RUSTLS */