/mandos/trunk : revision 1208

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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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* Contact the authors at <mandos@recompile.se>.

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*/

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#define _GNU_SOURCE /* pipe2(), O_CLOEXEC, setresgid(),

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setresuid(), asprintf(), getline(),

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basename() */

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#include <inttypes.h> /* uintmax_t, strtoumax(), PRIuMAX,

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PRIdMAX, intmax_t, uint32_t,

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SCNx32, SCNuMAX, SCNxMAX */

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#include <stddef.h> /* size_t, NULL */

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#define _GNU_SOURCE

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#include <inttypes.h> /* uintmax_t, PRIuMAX, PRIdMAX,

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intmax_t, uint32_t, SCNx32,

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SCNuMAX, SCNxMAX */

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#include <stddef.h> /* size_t */

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#include <sys/types.h> /* pid_t, uid_t, gid_t, getuid(),

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getpid() */

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#include <stdbool.h> /* bool, true, false */

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NSIG, sigismember(), SA_ONSTACK,

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SIG_DFL, SIG_IGN, SIGINT, SIGQUIT,

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SIGHUP, SIGSTOP, SIG_UNBLOCK */

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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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setresuid(), execv(), ssize_t,

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read(), dup3(), getuid(), dup(),

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STDERR_FILENO, pause(), write(),

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rmdir(), unlink(), getpid() */

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#include <stdlib.h> /* EXIT_SUCCESS, EXIT_FAILURE,

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malloc(), free(), realloc(),

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setenv(), calloc(), mkdtemp(),

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mkostemp() */

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malloc(), free(), strtoumax(),

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realloc(), setenv(), calloc(),

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mkdtemp(), mkostemp() */

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#include <iso646.h> /* not, or, and, xor */

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#include <error.h> /* error() */

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

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#include <string.h> /* strdup(), memcpy(),

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explicit_bzero(), memset(),

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strcmp(), strlen(), strncpy(),

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memcmp(), basename(), strerror() */

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memcmp(), basename() */

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#include <argz.h> /* argz_create(), argz_count(),

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argz_extract(), argz_next(),

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argz_add() */

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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, uint32_t */

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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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setresuid(), execv(), ssize_t,

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read(), dup3(), getuid(), dup(),

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STDERR_FILENO, pause(), write(),

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rmdir(), unlink(), getpid() */

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#include <sys/mman.h> /* munlock(), mlock() */

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#include <fcntl.h> /* O_CLOEXEC, O_NONBLOCK, fcntl(),

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F_GETFD, F_GETFL, FD_CLOEXEC,

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g_assert_null(), g_assert_false(),

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g_assert_cmpint(), g_assert_cmpuint(),

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g_test_skip(), g_assert_cmpstr(),

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g_test_message(), g_test_init(), g_test_add(),

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g_test_run(), GOptionContext,

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g_option_context_new(),

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g_test_init(), g_test_add(), g_test_run(),

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GOptionContext, g_option_context_new(),

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g_option_context_set_help_enabled(), FALSE,

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g_option_context_set_ignore_unknown_options(),

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gboolean, GOptionEntry, G_OPTION_ARG_NONE,

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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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}

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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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message_buffer = realloc(message_buffer, 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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break;

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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);