add coprocess facility

g10/status.c

@@ -22,26 +22,45 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <errno.h>
 #include <unistd.h>
+#ifdef USE_SHM_COPROCESSING
+  #ifdef HAVE_SYS_IPC_H
+    #include <sys/ipc.h>
+  #endif
+  #ifdef HAVE_SYS_SHM_H
+    #include <sys/shm.h>
+  #endif
+#endif
+#include "util.h"
 #include "status.h"
+#include "ttyio.h"
+#include "options.h"
+#include "main.h"
 
 static int fd = -1;
+#ifdef USE_SHM_COPROCESSING
+  static int shm_id = -1;
+  static volatile char *shm_area;
+  static size_t shm_size;
+  static int shm_is_locked;
+#endif /*USE_SHM_COPROCESSING*/
 
 void
-set_status_fd( int newfd )
+set_status_fd ( int newfd )
 {
     fd = newfd;
 }
 
 
 void
-write_status( int no )
+write_status ( int no )
 {
     write_status_text( no, NULL );
 }
 
 void
-write_status_text( int no, const char *text)
+write_status_text ( int no, const char *text)
 {
     const char *s;
 
@@ -64,6 +83,10 @@ write_status_text( int no, const char *text)
       case STATUS_TRUST_MARGINAL : s = "TRUST_MARGINAL\n"; break;
       case STATUS_TRUST_FULLY	 : s = "TRUST_FULLY\n"; break;
       case STATUS_TRUST_ULTIMATE : s = "TRUST_ULTIMATE\n"; break;
+      case STATUS_SHM_INFO	 : s = "SHM_INFO\n"; break;
+      case STATUS_SHM_GET	 : s = "SHM_GET\n"; break;
+      case STATUS_SHM_GET_BOOL	 : s = "SHM_GET_BOOL\n"; break;
+      case STATUS_SHM_GET_HIDDEN : s = "SHM_GET_HIDDEN\n"; break;
       default: s = "?\n"; break;
     }
 
@@ -78,3 +101,148 @@ write_status_text( int no, const char *text)
 	write( fd, s, strlen(s) );
 }
 
+
+#ifdef USE_SHM_COPROCESSING
+void
+init_shm_coprocessing ( ulong requested_shm_size, int lock_mem )
+{
+    char buf[100];
+
+    requested_shm_size = (requested_shm_size + 4095) & ~4095;
+    if ( requested_shm_size > 2 * 4096 )
+	log_fatal("too much shared memory requested; only 8k are allowed\n");
+    shm_size = 4096 /* one page for us */ + requested_shm_size;
+
+    /* FIXME: Need other permissions ... */
+    shm_id = shmget( IPC_PRIVATE, shm_size, IPC_CREAT | 0777 );
+    if ( shm_id == -1 )
+	log_fatal("can't get %uk of shared memory: %s\n",
+				(unsigned)shm_size/1024, strerror(errno));
+    shm_area = shmat( shm_id, 0, 0 );
+    if ( shm_area == (char*)-1 )
+	log_fatal("can't attach %uk shared memory: %s\n",
+				(unsigned)shm_size/1024, strerror(errno));
+    log_info("mapped %uk shared memory at %p, id=%d\n",
+			    (unsigned)shm_size/1024, shm_area, shm_id );
+    if( lock_mem ) {
+	if ( shmctl (shm_id, SHM_LOCK, 0) )
+	    log_info("Locking shared memory %d failed: %s\n",
+				shm_id, strerror(errno));
+	else
+	    shm_is_locked = 1;
+    }
+
+  #ifdef IPC_RMID_DEFERRED_RELEASE
+    if ( shmctl ( shm_id, IPC_RMID, 0) )
+	log_fatal("shmctl IPC_RMDID of %d failed: %s\n",
+					    shm_id, strerror(errno));
+  #else
+    #error Must add a cleanup function
+  #endif
+
+    /* write info; Protocol version, id, size, locked size */
+    sprintf( buf, "pv=1 pid=%d shmid=%d sz=%u lz=%u", (int)getpid(),
+	    shm_id, (unsigned)shm_size, shm_is_locked? (unsigned)shm_size:0 );
+    write_status_text( STATUS_SHM_INFO, buf );
+}
+
+
+/****************
+ * Request a string from client
+ * If bool, returns static string on true (do not free) or NULL for false
+ */
+static char *
+do_shm_get( const char *keyword, int hidden, int bool )
+{
+    size_t n;
+    byte *p;
+    char *string;
+
+    if( !shm_area )
+	BUG();
+
+    shm_area[0] = 0;  /* msb of length of control block */
+    shm_area[1] = 32; /* and lsb */
+    shm_area[2] = 1;  /* indicate that we are waiting on a reply */
+    shm_area[3] = 0;  /* clear data available flag */
+
+    write_status_text( bool? STATUS_SHM_GET_BOOL :
+		       hidden? STATUS_SHM_GET_HIDDEN : STATUS_SHM_GET, keyword );
+
+    do {
+	pause_on_sigusr(1);
+	if( shm_area[0] || shm_area[1] != 32 || shm_area[2] != 1 )
+	    log_fatal("client modified shm control block - abort\n");
+    } while( !shm_area[3] );
+    shm_area[2] = 0; /* reset request flag */
+    p = (byte*)shm_area+32;
+    n = p[0] << 8 | p[1];
+    p += 2;
+    if( n+32+2+1 > 4095 )
+	log_fatal("client returns too large data (%u bytes)\n", (unsigned)n );
+
+    if( bool )
+	return p[0]? "" : NULL;
+
+    string = hidden? m_alloc_secure( n+1 ) : m_alloc( n+1 );
+    memcpy(string, p, n );
+    string[n] = 0; /* make sure it is a string */
+    if( hidden ) /* invalidate the memory */
+	memset( p, 0, n );
+
+    return string;
+}
+
+#endif /* USE_SHM_COPROCESSING */
+
+
+int
+cpr_enabled()
+{
+  #ifdef USE_SHM_COPROCESSING
+    if( opt.shm_coprocess )
+	return 1;
+  #endif
+    return 0;
+}
+
+char *
+cpr_get( const char *keyword, const char *prompt )
+{
+  #ifdef USE_SHM_COPROCESSING
+    if( opt.shm_coprocess )
+	return do_shm_get( keyword, 0, 0 );
+  #endif
+    return tty_get( prompt );
+}
+
+char *
+cpr_get_hidden( const char *keyword, const char *prompt )
+{
+  #ifdef USE_SHM_COPROCESSING
+    if( opt.shm_coprocess )
+	return do_shm_get( keyword, 1, 0 );
+  #endif
+    return tty_get_hidden( prompt );
+}
+
+void
+cpr_kill_prompt(void)
+{
+  #ifdef USE_SHM_COPROCESSING
+    if( opt.shm_coprocess )
+	return;
+  #endif
+    return tty_kill_prompt();
+}
+
+int
+cpr_get_answer_is_yes( const char *keyword, const char *prompt )
+{
+  #ifdef USE_SHM_COPROCESSING
+    if( opt.shm_coprocess )
+	return !!do_shm_get( keyword, 0, 1 );
+  #endif
+    return tty_get_answer_is_yes( prompt );
+}
+