better ipc: using POSIX (semaphores && msg queues)

8 files changed, 174 insertions, 81 deletions

diff --git a/.gitignore b/.gitignore
index 4b8fd3a..3e2ffcd 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,4 +2,5 @@
 /tests/producer
 /tests/consumer
 /tests/semtest
+/tests/mqtest
 *.swp
diff --git a/Makefile b/Makefile
index fe89038..1abb87a 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
 CFLAGS ?= $(shell ncurses5-config --cflags) -Wall -D_GNU_SOURCE=1
 DBGFLAGS = -g
-LDFLAGS ?= $(shell ncurses5-config --libs) -pthread
+LDFLAGS ?= $(shell ncurses5-config --libs) -pthread -lrt
 CC ?= gcc
 INSTALL ?= install
 VERSION ?= $(shell if [ -d ./.git ]; then echo -n "git-"; git rev-parse --short HEAD; else echo "1.2a"; fi)
diff --git a/config.h b/config.h
index 26fdb3c..a559771 100644
--- a/config.h
+++ b/config.h
@@ -5,6 +5,10 @@
 #define DEFAULT_FIFO "/lib/cryptsetup/passfifo"
 #define SHTDWN_CMD "echo 'o' >/proc/sysrq-trigger"
 
+#define SEM_GUI "/naskpass-gui"
+#define SEM_INP "/naskpass-input"
+#define MSQ_PWD "/naskpass-passwd"
+
 #ifdef _VERSION
 #define VERSION _VERSION
 #else
diff --git a/main.c b/main.c
index 670503e..c40265d 100644
--- a/main.c
+++ b/main.c
@@ -8,6 +8,9 @@
 #include <sys/types.h>
 #include <sys/wait.h>
 #include <fcntl.h>
+#include <semaphore.h>
+#include <time.h>
+#include <mqueue.h>
 
 #include "ui_ani.h"
 #include "ui_input.h"
@@ -16,7 +19,9 @@
 #include "config.h"
 
 
-static bool ui_active = true;
+static sem_t *sp_ui, *sp_input;
+static mqd_t mq_passwd;
+
 
 static void
 usage(char *arg0)
@@ -51,23 +56,6 @@ check_fifo(char *fifo_path)
   return (false);
 }
 
-/* stolen from http://www.gnu.org/software/libc/manual/html_node/Waiting-for-I_002fO.html */
-static int
-input_timeout(int filedes, unsigned int seconds)
-{
-  fd_set set;
-  struct timeval timeout;
-
-  /* Initialize the file descriptor set. */
-  FD_ZERO (&set);
-  FD_SET (filedes, &set);
-  /* Initialize the timeout data structure. */
-  timeout.tv_sec = seconds;
-  timeout.tv_usec = 0;
-  /* select returns 0 if timeout, 1 if input available, -1 if error. */
-  return TEMP_FAILURE_RETRY(select(FD_SETSIZE, &set, NULL, NULL, &timeout));
-}
-
 int
 run_cryptcreate(char *pass, char *crypt_cmd)
 {
@@ -80,22 +68,65 @@ run_cryptcreate(char *pass, char *crypt_cmd)
   return (retval);
 }
 
+void sigfunc(int signal)
+{
+  switch (signal) {
+    case SIGTERM:
+    case SIGKILL:
+    case SIGINT:
+      sem_trywait(sp_ui);
+      sem_trywait(sp_input);
+      break;
+  }
+}
+
 int
 main(int argc, char **argv)
 {
-  int ffd, c_status, opt;
+  int ret = EXIT_FAILURE, ffd = -1, c_status, opt, i_sval;
   pid_t child;
   char pbuf[MAX_PASSWD_LEN+1];
   char *fifo_path = NULL;
   char *crypt_cmd = NULL;
+  struct timespec ts_sem_input;
+  struct mq_attr mq_attr;
 
-  memset(pbuf, '\0', MAX_PASSWD_LEN+1);
+  signal(SIGINT, sigfunc);
+  signal(SIGTERM, sigfunc);
+  signal(SIGKILL, sigfunc);
+
+  if ( clock_gettime(CLOCK_REALTIME, &ts_sem_input) == -1 ) {
+    fprintf(stderr, "%s: clock get time error: %d (%s)\n", argv[0], errno, strerror(errno));
+    goto error;
+  }
+  if ( (sp_ui = sem_open(SEM_GUI, O_CREAT | O_EXCL, S_IRUSR | S_IWUSR, 0)) == SEM_FAILED ||
+          (sp_input = sem_open(SEM_INP, O_CREAT | O_EXCL, S_IRUSR | S_IWUSR, 0)) == SEM_FAILED ||
+(mq_passwd = mq_open(MSQ_PWD, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR, NULL)) == (mqd_t) -1 ) {
+    if ( errno == EEXIST ) {
+      fprintf(stderr, "%s: already started?\n", argv[0]);
+    } else {
+      fprintf(stderr, "%s: can not create semaphore: %d (%s)\n", argv[0], errno, strerror(errno));
+    }
+    goto error;
+  }
+  if ( mq_getattr(mq_passwd, &mq_attr) == 0 ) {
+    mq_attr.mq_maxmsg = 2;
+    mq_attr.mq_msgsize = MAX_PASSWD_LEN;
+    if ( mq_setattr(mq_passwd, &mq_attr, NULL) != 0 ) {
+      fprintf(stderr, "%s: can not SET message queue attributes: %d (%s)\n", argv[0], errno, strerror(errno));
+      goto error;
+    }
+  } else {
+    fprintf(stderr, "%s: can not GET message queue attributes: %d (%s)\n", argv[0], errno, strerror(errno));
+    goto error;
+  }
 
+  memset(pbuf, '\0', MAX_PASSWD_LEN+1);
   while ((opt = getopt(argc, argv, "hf:c:")) != -1) {
     switch (opt) {
       case 'h':
         usage(argv[0]);
-        exit(EXIT_SUCCESS);
+        goto error;
       case 'f':
         fifo_path = strdup(optarg);
         break;
@@ -104,56 +135,66 @@ main(int argc, char **argv)
         break;
       default:
         usage(argv[0]);
-        exit(EXIT_FAILURE);
+        goto error;
     }
   }
   if (optind < argc) {
     fprintf(stderr, "%s: I dont understand you.\n\n", argv[0]);
     usage(argv[0]);
-    exit(EXIT_FAILURE);
+    goto error;
   }
   if (fifo_path == NULL) fifo_path = strdup(DEFAULT_FIFO);
 
   if (check_fifo(fifo_path) == false) {
     usage(argv[0]);
-    exit(EXIT_FAILURE);
+    goto error;
   }
   if ((ffd = open(fifo_path, O_NONBLOCK | O_RDWR)) < 0) {
-    fprintf(stderr, "fifo: %s\n", fifo_path);
-    perror("open");
-    exit(EXIT_FAILURE);
+    fprintf(stderr, "%s: fifo '%s' error: %d (%s)\n", argv[0], fifo_path, errno, strerror(errno));
+    goto error;
   }
 
   if ((child = fork()) == 0) {
     /* child */
-    ui_active = true;
-    do_ui(ffd);
-    ui_active = false;
+    fclose(stderr);
+    /* Slave process: TUI */
+    sem_post(sp_ui);
+    do_ui();
   } else if (child > 0) {
     /* parent */
     fclose(stdin);
-    while (input_timeout(ffd, 1) == 0) {
-      usleep(100000);
-      if (ui_active == true) {
-        // TODO: smthng
+    fclose(stdout);
+    /* Master process: mainloop (read passwd from message queue or fifo and exec cryptcreate */
+    while ( sem_getvalue(sp_ui, &i_sval) == 0 && i_sval > 0 ) {
+      if ( sem_getvalue(sp_input, &i_sval) == 0 && i_sval > 0 ) {
+        if (read(ffd, pbuf, MAX_PASSWD_LEN) > 0) {
+          if (run_cryptcreate(pbuf, crypt_cmd) != 0) {
+            fprintf(stderr, "cryptcreate error\n");
+          }
+        }
+      } else if ( mq_receive(mq_passwd, pbuf, MAX_PASSWD_LEN, NULL) > 0 ) {
+exit(77);
       }
+      usleep(100000);
     }
-    stop_ui();
     wait(&c_status);
-    if (read(ffd, pbuf, MAX_PASSWD_LEN) > 0) {
-      if (run_cryptcreate(pbuf, crypt_cmd) != 0) {
-        fprintf(stderr, "cryptcreate error\n");
-      }
-    }
     memset(pbuf, '\0', MAX_PASSWD_LEN+1);
   } else {
     /* fork error */
     perror("fork");
-    exit(EXIT_FAILURE);
+    goto error;
   }
 
-  close(ffd);
+  ret = EXIT_SUCCESS;
+error:
+  if (ffd >= 0) close(ffd);
   if (crypt_cmd != NULL) free(crypt_cmd);
-  free(fifo_path);
-  return (EXIT_SUCCESS);
+  if (fifo_path != NULL) free(fifo_path);
+  sem_close(sp_ui);
+  sem_close(sp_input);
+  mq_close(mq_passwd);
+  sem_unlink(SEM_GUI);
+  sem_unlink(SEM_INP);
+  mq_unlink(MSQ_PWD);
+  exit(ret);
 }
diff --git a/tests/Makefile b/tests/Makefile
index 22a5469..5a041e6 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -1,5 +1,5 @@
 CFLAGS = -Wall
-LDFLAGS = -lpthread
+LDFLAGS = -lpthread -lrt
 CC = gcc
 SOURCES = $(wildcard *.c)
 BINARIES = $(patsubst %.c,%,$(SOURCES))
diff --git a/tests/mqtest.c b/tests/mqtest.c
new file mode 100644
index 0000000..56c2d2b
--- /dev/null
+++ b/tests/mqtest.c
@@ -0,0 +1,46 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <mqueue.h>
+
+#include <assert.h>
+
+
+static mqd_t mq_test;
+static const size_t bufsiz = 256;
+
+int main(int argc, char **argv)
+{
+  struct mq_attr m_attr;
+  char buf[bufsiz], recv[bufsiz];
+
+  memset(buf, '\0', bufsiz);
+  memset(buf, '\0', bufsiz);
+  if (argc > 1)
+    strncpy(buf, argv[1], bufsiz-1);
+
+  mq_unlink("/testmq");
+  assert( (mq_test = mq_open( "/testmq", O_CREAT | O_EXCL | O_RDWR  | O_NONBLOCK, S_IRUSR | S_IWUSR, NULL )) != (mqd_t)-1 );
+  assert( mq_getattr(mq_test, &m_attr) == 0 );
+  printf("flags.....: %ld\n"
+         "maxmsg....: %ld\n"
+         "msgsize...: %ld\n"
+         "curmsg....: %ld\n",
+         m_attr.mq_flags, m_attr.mq_maxmsg, m_attr.mq_msgsize, m_attr.mq_curmsgs);
+
+  m_attr.mq_msgsize = bufsiz-1;
+  assert ( mq_setattr(mq_test, &m_attr, NULL) == 0 );
+  assert ( mq_send(mq_test, buf, bufsiz-1, 0) == 0 );
+  assert ( mq_getattr(mq_test, &m_attr) == 0 );
+  printf("new msgsize...: %ld\n"
+         "new curmsg....: %ld\n",
+         m_attr.mq_msgsize, m_attr.mq_curmsgs);
+  assert ( mq_receive(mq_test, recv, bufsiz-1, 0) > 0 );
+
+  printf("RECV: %s\n", recv);
+
+  return 0;
+}
+
diff --git a/ui.c b/ui.c
index 58cc226..9d0abae 100644
--- a/ui.c
+++ b/ui.c
@@ -9,6 +9,9 @@
 #include <ncurses.h>
 #include <sys/time.h>
 #include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <mqueue.h>
 #include <signal.h>
 
 #include "ui.h"
@@ -30,17 +33,18 @@
 #define STRLEN(s) (sizeof(s)/sizeof(s[0]))
 
 
-static int ffd;
 static unsigned int max_x, max_y;
 static WINDOW *wnd_main;
 static struct nask_ui *nui = NULL;
 static pthread_t thrd;
-static bool active, passwd_from_ui;
+static bool active;
 static unsigned int atmout = APP_TIMEOUT;
 static pthread_cond_t cnd_update = PTHREAD_COND_INITIALIZER;
 static pthread_mutex_t mtx_update = PTHREAD_MUTEX_INITIALIZER;
 static pthread_mutex_t mtx_busy = PTHREAD_MUTEX_INITIALIZER;
 static sem_t sem_rdy;
+static sem_t *sp_ui, *sp_input;
+static mqd_t mq_passwd;
 
 
 void
@@ -183,7 +187,6 @@ static int
 run_ui_thrd(void) {
   pthread_mutex_lock(&mtx_busy);
   active = true;
-  passwd_from_ui = false;
   pthread_cond_signal(&cnd_update);
   pthread_mutex_unlock(&mtx_busy);
   return (pthread_create(&thrd, NULL, &ui_thrd, NULL));
@@ -205,15 +208,15 @@ stop_ui_thrd(void)
 }
 
 static int
-send_passwd(int fifo_fd, char *passwd, size_t len)
+mq_passwd_send(char *passwd, size_t len)
 {
-  if (write(fifo_fd, passwd, len) != len) {
-    memset(passwd, '\0', len);
-    return (errno);
-  } else {
-    memset(passwd, '\0', len);
-    return (0);
+  struct mq_attr m_attr;
+
+  if (mq_send(mq_passwd, "hellomq", 7, 0) == 0 && mq_getattr(mq_passwd, &m_attr) == 0) {
+    return m_attr.mq_curmsgs;
   }
+  memset(passwd, '\0', len);
+  return -1;
 }
 
 static bool
@@ -224,9 +227,9 @@ process_key(char key, struct input *a, WINDOW *win)
   atmout = APP_TIMEOUT;
   switch (key) {
     case UIKEY_ENTER:
-      send_passwd(ffd, a->input, a->input_len);
-      passwd_from_ui = true;
-      retval = false;
+      if ( mq_passwd_send(a->input, a->input_len) > 0 ) {
+        retval = false;
+      } else retval = true;
       break;
     case UIKEY_BACKSPACE:
       del_input(win, a);
@@ -262,18 +265,21 @@ infownd_update(WINDOW *win, struct txtwindow *tw)
 }
 
 int
-do_ui(int fifo_fd)
+do_ui(void)
 {
   struct input *pw_input;
   struct anic *heartbeat;
   struct statusbar *higher, *lower;
   struct txtwindow *infownd;
   char key = '\0';
-  char *title;
+  char *title = NULL;
+  int i_sval = -1, ret = DOUI_ERR;
 
   asprintf(&title, "/* %s-%s */", PKGNAME, VERSION);
-  ffd = fifo_fd;
-  if (sem_init(&sem_rdy, 0, 0) == -1) {
+  sp_ui = sem_open(SEM_GUI, 0, 0, 0);
+  sp_input = sem_open(SEM_INP, 0, 0, 0);
+  mq_passwd = mq_open(MSQ_PWD, O_WRONLY, S_IWUSR, NULL);
+  if ( sem_init(&sem_rdy, 0, 0) == -1 || !sp_ui || !sp_input || mq_passwd == (mqd_t)-1 ) {
     perror("init semaphore");
     goto error;
   }
@@ -295,7 +301,7 @@ do_ui(int fifo_fd)
   }
   sem_wait(&sem_rdy);
   wtimeout(wnd_main, 1000);
-  while (active == true) {
+  while ( active && sem_getvalue(sp_ui, &i_sval) == 0 && i_sval > 0 ) {
     if ((key = wgetch(wnd_main)) == '\0') {
       break;
     }
@@ -308,6 +314,7 @@ do_ui(int fifo_fd)
     do_ui_update(false);
     pthread_mutex_unlock(&mtx_busy);
   }
+  ui_thrd_force_update();
   stop_ui_thrd();
   unregister_ui_elt(lower);
   unregister_ui_elt(higher);
@@ -319,19 +326,16 @@ do_ui(int fifo_fd)
   free_statusbar(lower);
   free_txtwindow(infownd);
   free_ui();
-  return (DOUI_OK);
+  ret = DOUI_OK;
+  sem_trywait(sp_ui);
+  mq_close(mq_passwd);
 error:
-  free(title);
-  return (DOUI_ERR);
-}
-
-bool
-is_passwd_from_ui(void)
-{
-  bool ret;
-  pthread_mutex_lock(&mtx_busy);
-  ret = passwd_from_ui;
-  pthread_mutex_unlock(&mtx_busy);
-  return (ret);
+  if (title) free(title);
+  if (sp_ui) sem_close(sp_ui);
+  if (sp_input) sem_close(sp_input);
+  title = NULL;
+  sp_ui = NULL;
+  sp_input = NULL;
+  return ret;
 }
 
diff --git a/ui.h b/ui.h
index 77a5bc9..a34ca10 100644
--- a/ui.h
+++ b/ui.h
@@ -52,12 +52,9 @@ void
 free_ui(void);
 
 int
-do_ui(int fifo_fd);
+do_ui(void);
 
 void
 stop_ui(void);
 
-bool
-is_passwd_from_ui(void);
-
 #endif