/mandos/release : revision 393

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/*

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* Mandos password agent - Simple password agent to run Mandos client

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*

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*

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* This file is part of Mandos.

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*

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#include <sysexits.h> /* EX_USAGE, EX_OSERR, EX_OSFILE */

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#include <errno.h> /* errno, error_t, EACCES,

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ENAMETOOLONG, ENOENT, ENOTDIR,

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ENOMEM, EEXIST, ECHILD, EPERM,

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EEXIST, ECHILD, EPERM, ENOMEM,

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EAGAIN, EINTR, ENOBUFS, EADDRINUSE,

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ECONNREFUSED, ECONNRESET,

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ETOOMANYREFS, EMSGSIZE, EBADF,

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ARGP_ERR_UNKNOWN, ARGP_KEY_ARGS,

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struct argp, argp_parse(),

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ARGP_NO_EXIT */

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#include <stdint.h> /* SIZE_MAX */

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#include <unistd.h> /* uid_t, gid_t, close(), pipe2(),

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fork(), _exit(), dup2(),

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STDOUT_FILENO, setresgid(),

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IN_EXCL_UNLINK, IN_ONLYDIR,

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struct inotify_event */

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#include <fnmatch.h> /* fnmatch(), FNM_FILE_NAME */

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#include <stdio.h> /* asprintf(), FILE, stderr, fopen(),

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fclose(), getline(), sscanf(),

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feof(), ferror(), rename(),

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fdopen(), fprintf(), fscanf() */

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#include <stdio.h> /* asprintf(), FILE, fopen(),

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getline(), sscanf(), feof(),

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ferror(), fclose(), stderr,

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rename(), fdopen(), fprintf(),

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fscanf() */

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#include <glib.h> /* GKeyFile, g_key_file_free(), g_key_file_new(),

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GError, g_key_file_load_from_file(),

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G_KEY_FILE_NONE, TRUE, G_FILE_ERROR_NOENT,

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mono_microsecs next_run;

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} __attribute__((designated_init)) task_queue;

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/* "task_func" - A function type for task functions

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/* "func_type" - A function type for task functions

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I.e. functions for the code which runs when a task is run, all have

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this type */

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__attribute__((nonnull, warn_unused_result))

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bool add_to_queue(task_queue *const queue, const task_context task){

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if((queue->length + 1) > (SIZE_MAX / sizeof(task_context))){

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/* overflow */

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error(0, ENOMEM, "Failed to allocate %" PRIuMAX

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" tasks for queue->tasks", (uintmax_t)(queue->length + 1));

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errno = ENOMEM;

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return false;

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}

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const size_t needed_size = sizeof(task_context)*(queue->length + 1);

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if(needed_size > (queue->allocated)){

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task_context *const new_tasks = realloc(queue->tasks,

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}

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close(pipefds[1]);

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if(pid == -1){

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error(0, errno, "Failed to fork()");

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close(pipefds[0]);

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return false;

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}

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if(not add_to_queue(queue, (task_context){

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.func=wait_for_mandos_client_exit,

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.pid=pid,

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bool *const password_is_read = task.password_is_read;

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/* We use the GLib "Key-value file parser" functions to parse the

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question file. See <https://systemd.io/PASSWORD_AGENTS/> for

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specification of contents */

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question file. See <https://www.freedesktop.org/wiki/Software

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/systemd/PasswordAgents/> for specification of contents */

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__attribute__((nonnull))

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void cleanup_g_key_file(GKeyFile **key_file){

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if(*key_file != NULL){

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not. You may but don't have to include a final NUL byte in

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your message.

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— <https://systemd.io/PASSWORD_AGENTS/> (Tue, 15 Sep 2020

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14:24:20 GMT)

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— <https://www.freedesktop.org/wiki/Software/systemd/

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PasswordAgents/> (Wed 08 Oct 2014 02:14:28 AM UTC)

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*/

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send_buffer[0] = '+'; /* Prefix with "+" */

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/* Always add an extra NUL */

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errno = 0;

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ssize_t ssret = send(fd, send_buffer, send_buffer_length,

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MSG_NOSIGNAL);

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const error_t saved_errno = (ssret < 0) ? errno : 0;

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const error_t saved_errno = errno;

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#if defined(__GLIBC_PREREQ) and __GLIBC_PREREQ(2, 25)

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explicit_bzero(send_buffer, send_buffer_length);

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#else

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/* Retry, below */

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break;

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case EMSGSIZE:

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error(0, saved_errno, "Password of size %" PRIuMAX

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" is too big", (uintmax_t)password->length);

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error(0, 0, "Password of size %" PRIuMAX " is too big",

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(uintmax_t)password->length);

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#if __GNUC__ < 7

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/* FALLTHROUGH */

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#else

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#endif

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case 0:

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if(ssret >= 0 and ssret < (ssize_t)send_buffer_length){

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error(0, 0, "Password only partially sent to socket %s: %"

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PRIuMAX " out of %" PRIuMAX " bytes sent", filename,

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(uintmax_t)ssret, (uintmax_t)send_buffer_length);

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error(0, 0, "Password only partially sent to socket");

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}

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#if __GNUC__ < 7

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/* FALLTHROUGH */

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g_assert_true(queue->tasks[0].func == dummy_func);

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}

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static void test_add_to_queue_overflow(__attribute__((unused))

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test_fixture *fixture,

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__attribute__((unused))

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gconstpointer user_data){

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__attribute__((cleanup(cleanup_queue)))

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task_queue *queue = create_queue();

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g_assert_nonnull(queue);

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g_assert_true(queue->length == 0);

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queue->length = SIZE_MAX / sizeof(task_context); /* fake max size */

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FILE *real_stderr = stderr;

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FILE *devnull = fopen("/dev/null", "we");

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g_assert_nonnull(devnull);

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stderr = devnull;

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const bool ret = add_to_queue(queue,

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(task_context){ .func=dummy_func });

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g_assert_true(errno == ENOMEM);

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g_assert_false(ret);

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stderr = real_stderr;

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g_assert_cmpint(fclose(devnull), ==, 0);

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queue->length = 0; /* Restore real size */

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}

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static void dummy_func(__attribute__((unused))

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const task_context task,

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__attribute__((unused))

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}

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exit(EXIT_SUCCESS);

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}

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if(pid == -1){

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error(EXIT_FAILURE, errno, "Failed to fork()");

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}

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int status;

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waitpid(pid, &status, 0);

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if(WIFEXITED(status) and (WEXITSTATUS(status) == EXIT_SUCCESS)){

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char write_data[PIPE_BUF];

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{

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/* Construct test password buffer */

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/* Start with + since that is what the real protocol uses */

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/* Start with + since that is what the real procotol uses */

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write_data[0] = '+';

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/* Set a special character at string end just to mark the end */

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write_data[sizeof(write_data)-2] = 'y';

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char *const filename = strdup("/nonexistent/socket");

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__attribute__((cleanup(string_set_clear)))

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string_set cancelled_filenames = {};

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int socketfds[2];

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/* Find a message size which triggers EMSGSIZE */

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__attribute__((cleanup(cleanup_string)))

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char *message_buffer = NULL;

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size_t message_size = PIPE_BUF + 1;

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for(ssize_t ssret = 0; ssret >= 0; message_size += 1024){

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if(message_size >= 1024*1024*1024){ /* 1 GiB */

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g_test_skip("Skipping EMSGSIZE test: Will not try 1GiB");

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return;

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}

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free(message_buffer);

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message_buffer = malloc(message_size);

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if(message_buffer == NULL){

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g_test_skip("Skipping EMSGSIZE test");

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g_test_message("Failed to malloc() %" PRIuMAX " bytes",

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(uintmax_t)message_size);

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return;

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}

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/* Fill buffer with 'x' */

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memset(message_buffer, 'x', message_size);

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/* Create a new socketpair for each message size to avoid having

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to empty the pipe by reading the message to a separate buffer

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*/

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g_assert_cmpint(socketpair(PF_LOCAL, SOCK_DGRAM

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| SOCK_NONBLOCK | SOCK_CLOEXEC, 0,

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socketfds), ==, 0);

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ssret = send(socketfds[1], message_buffer, message_size,

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MSG_NOSIGNAL);

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error_t saved_errno = errno;

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g_assert_cmpint(close(socketfds[0]), ==, 0);

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g_assert_cmpint(close(socketfds[1]), ==, 0);

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if(ssret < 0){

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if(saved_errno != EMSGSIZE) {

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g_test_skip("Skipping EMSGSIZE test");

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g_test_message("Error on send(): %s", strerror(saved_errno));

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return;

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}

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} else if(ssret != (ssize_t)message_size){

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g_test_skip("Skipping EMSGSIZE test");

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g_test_message("Partial send(): %" PRIuMAX " of %" PRIdMAX

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" bytes", (uintmax_t)ssret,

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(intmax_t)message_size);

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return;

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}

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}

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g_test_message("EMSGSIZE triggered by %" PRIdMAX " bytes",

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(intmax_t)message_size);

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buffer password = {

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.data=message_buffer,

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.length=message_size - 2, /* Compensate for added '+' and NUL */

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.allocated=message_size,

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const size_t oversized = 1024*1024; /* Limit seems to be 212960 */

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__attribute__((cleanup(cleanup_buffer)))

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buffer password = {

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.data=malloc(oversized),

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.length=oversized,

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.allocated=oversized,

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};

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g_assert_nonnull(password.data);

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if(mlock(password.data, password.allocated) != 0){

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g_assert_true(errno == EPERM or errno == ENOMEM);

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}

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/* Construct test password buffer */

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/* Start with + since that is what the real procotol uses */

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password.data[0] = '+';

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/* Set a special character at string end just to mark the end */

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password.data[oversized-3] = 'y';

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/* Set NUL at buffer end, as suggested by the protocol */

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password.data[oversized-2] = '\0';

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/* Fill rest of password with 'x' */

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memset(password.data+1, 'x', oversized-3);

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__attribute__((cleanup(cleanup_queue)))

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task_queue *queue = create_queue();

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g_assert_nonnull(queue);

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int socketfds[2];

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g_assert_cmpint(socketpair(PF_LOCAL, SOCK_DGRAM

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| SOCK_NONBLOCK | SOCK_CLOEXEC, 0,

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socketfds), ==, 0);

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test_add("/parse_arguments/mixed", test_parse_arguments_mixed);

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test_add("/queue/create", test_create_queue);

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test_add("/queue/add", test_add_to_queue);

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test_add("/queue/add/overflow", test_add_to_queue_overflow);

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test_add("/queue/has_question/empty",

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test_queue_has_question_empty);

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test_add("/queue/has_question/false",

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g_option_context_set_help_enabled(context, FALSE);

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g_option_context_set_ignore_unknown_options(context, TRUE);

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gboolean should_run_tests = FALSE;

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gboolean run_tests = FALSE;

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GOptionEntry entries[] = {

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{ "test", 0, 0, G_OPTION_ARG_NONE,

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&should_run_tests, "Run tests", NULL },

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&run_tests, "Run tests", NULL },

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{ NULL }

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};

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g_option_context_add_main_entries(context, entries, NULL);

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}

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g_option_context_free(context);

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return should_run_tests != FALSE;

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return run_tests != FALSE;

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}