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/*
* Copyright 2019 Andreas Schneider <asn@cryptomilk.org>
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <stdbool.h>
#define LIBSSH_STATIC 1
#include <libssh/libssh.h>
#include <libssh/callbacks.h>
static int auth_callback(const char *prompt,
char *buf,
size_t len,
int echo,
int verify,
void *userdata)
{
(void)prompt; /* unused */
(void)echo; /* unused */
(void)verify; /* unused */
(void)userdata; /* unused */
snprintf(buf, len, "secret");
return 0;
}
struct ssh_callbacks_struct cb = {
.userdata = NULL,
.auth_function = auth_callback,
};
static void select_loop(ssh_session session, ssh_channel channel)
{
ssh_connector connector_in, connector_out, connector_err;
ssh_event event = ssh_event_new();
/* stdin */
connector_in = ssh_connector_new(session);
ssh_connector_set_out_channel(connector_in, channel, SSH_CONNECTOR_STDINOUT);
ssh_connector_set_in_fd(connector_in, 0);
ssh_event_add_connector(event, connector_in);
/* stdout */
connector_out = ssh_connector_new(session);
ssh_connector_set_out_fd(connector_out, 1);
ssh_connector_set_in_channel(connector_out, channel, SSH_CONNECTOR_STDINOUT);
ssh_event_add_connector(event, connector_out);
/* stderr */
connector_err = ssh_connector_new(session);
ssh_connector_set_out_fd(connector_err, 2);
ssh_connector_set_in_channel(connector_err, channel, SSH_CONNECTOR_STDERR);
ssh_event_add_connector(event, connector_err);
while (ssh_channel_is_open(channel)) {
ssh_event_dopoll(event, 60000);
}
ssh_event_remove_connector(event, connector_in);
ssh_event_remove_connector(event, connector_out);
ssh_event_remove_connector(event, connector_err);
ssh_connector_free(connector_in);
ssh_connector_free(connector_out);
ssh_connector_free(connector_err);
ssh_event_free(event);
}
int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
{
ssh_session session = NULL;
ssh_channel channel = NULL;
const char *env = NULL;
int socket_fds[2] = {-1, -1};
ssize_t nwritten;
bool no = false;
int rc;
/* Set up the socket to send data */
rc = socketpair(AF_UNIX, SOCK_STREAM, 0, socket_fds);
assert(rc == 0);
nwritten = send(socket_fds[1], data, size, 0);
assert((size_t)nwritten == size);
rc = shutdown(socket_fds[1], SHUT_WR);
assert(rc == 0);
ssh_init();
session = ssh_new();
assert(session != NULL);
env = getenv("LIBSSH_VERBOSITY");
if (env != NULL && strlen(env) > 0) {
ssh_options_set(session, SSH_OPTIONS_LOG_VERBOSITY_STR, env);
}
rc = ssh_options_set(session, SSH_OPTIONS_FD, &socket_fds[0]);
assert(rc == 0);
rc = ssh_options_set(session, SSH_OPTIONS_HOST, "127.0.0.1");
assert(rc == 0);
rc = ssh_options_set(session, SSH_OPTIONS_USER, "alice");
assert(rc == 0);
rc = ssh_options_set(session, SSH_OPTIONS_CIPHERS_C_S, "none");
assert(rc == 0);
rc = ssh_options_set(session, SSH_OPTIONS_CIPHERS_S_C, "none");
assert(rc == 0);
rc = ssh_options_set(session, SSH_OPTIONS_HMAC_C_S, "none");
assert(rc == 0);
rc = ssh_options_set(session, SSH_OPTIONS_HMAC_S_C, "none");
assert(rc == 0);
rc = ssh_options_set(session, SSH_OPTIONS_PROCESS_CONFIG, &no);
assert(rc == 0);
ssh_callbacks_init(&cb);
ssh_set_callbacks(session, &cb);
rc = ssh_connect(session);
if (rc != SSH_OK) {
goto out;
}
rc = ssh_userauth_none(session, NULL);
if (rc != SSH_OK) {
goto out;
}
channel = ssh_channel_new(session);
assert(channel != NULL);
rc = ssh_channel_open_session(channel);
if (rc != SSH_OK) {
goto out;
}
rc = ssh_channel_request_exec(channel, "ls");
assert(rc == SSH_OK);
select_loop(session, channel);
out:
ssh_channel_free(channel);
ssh_disconnect(session);
ssh_free(session);
ssh_finalize();
close(socket_fds[0]);
close(socket_fds[1]);
return 0;
}
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