X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/35c0995dde0c37486681630acdd8d26659a4732e..3e248c3b5b309bc03eb5f70762d3f5671d51f996:/progs/pixie.c

diff --git a/progs/pixie.c b/progs/pixie.c
index 667a588..4380703 100644
--- a/progs/pixie.c
+++ b/progs/pixie.c
@@ -83,6 +83,7 @@ static unsigned flags = 0;
 
 #define F_SYSLOG 1u
 #define F_FETCH 2u
+#define F_REPLACE 4u
 
 /*----- Event logging -----------------------------------------------------*/
 
@@ -96,7 +97,7 @@ static unsigned flags = 0;
  * Use:		Writes out a timestamped log message.
  */
 
-static void pxlog(const char *p, ...)
+static void PRINTF_LIKE(1, 2) pxlog(const char *p, ...)
 {
   dstr d = DSTR_INIT;
   va_list ap;
@@ -587,21 +588,27 @@ static void pixserv_expire(struct timeval *tv, void *p)
  *		@const char *p@ = pointer to skeleton string
  *		@...@ = other arguments to fill in
  *
- * Returns:	---
+ * Returns:	Zero on success, @-1@ on error.
  *
  * Use:		Formats a string and emits it to the output file.
  */
 
-static void pixserv_write(pixserv *px, const char *p, ...)
+static int PRINTF_LIKE(2, 3) pixserv_write(pixserv *px, const char *p, ...)
 {
   dstr d = DSTR_INIT;
   va_list ap;
+  int rc;
 
   va_start(ap, p);
   dstr_vputf(&d, p, &ap);
-  write(px->fd, d.buf, d.len);
+  rc = write(px->fd, d.buf, d.len);
   va_end(ap);
   dstr_destroy(&d);
+  if (rc < 0) {
+    pxlog("failed to write to client: %s (closing)", strerror(errno));
+    return (-1);
+  }
+  return (0);
 }
 
 /* --- @pixserv_timeout@ --- *
@@ -654,13 +661,7 @@ static void pixserv_line(char *s, size_t len, void *p)
 
   if (!(px->f & px_stdin))
     sel_rmtimer(&px->timer);
-  if (!s) {
-    if (px->fd != px->b.reader.fd)
-      close(px->fd);
-    selbuf_destroy(&px->b);
-    close(px->b.reader.fd);
-    return;
-  }
+  if (!s) goto close;
 
   /* --- Fiddle the timeout --- */
 
@@ -681,17 +682,18 @@ static void pixserv_line(char *s, size_t len, void *p)
   /* --- Handle a help request --- */
 
   if (strcmp(q, "help") == 0) {
-    pixserv_write(px, "\
+    if (pixserv_write(px, "\
 INFO Commands supported:\n\
-INFO HELP\n\
-INFO LIST\n\
-INFO PASS tag [expire]\n\
-INFO VERIFY tag [expire]\n\
-INFO FLUSH [tag]\n\
-INFO SET tag [expire] -- phrase\n\
-INFO QUIT\n\
+INFO flush [TAG]\n\
+INFO help\n\
+INFO list\n\
+INFO pass TAG [EXPIRE]\n\
+INFO quit\n\
+INFO set TAG [EXPIRE] -- PHRASE\n\
+INFO verify TAG [EXPIRE]\n\
 OK\n\
-");
+"))
+      goto close;
   }
 
   /* --- List the passphrases --- */
@@ -700,16 +702,18 @@ OK\n\
     phrase *p;
 
     for (p = p_head; p; p = p->next) {
-      if (!p->t)
-	pixserv_write(px, "ITEM %s no-expire\n", p->tag);
-      else {
+      if (!p->t) {
+	if (pixserv_write(px, "ITEM %s no-expire\n", p->tag)) goto close;
+      } else {
 	struct timeval tv;
 	gettimeofday(&tv, 0);
 	TV_SUB(&tv, &p->timer.tv, &tv);
-	pixserv_write(px, "ITEM %s %i\n", p->tag, tv.tv_sec);
+	if (pixserv_write(px, "ITEM %s %lu\n",
+			  p->tag, (unsigned long)tv.tv_sec))
+	  goto close;
       }
     }
-    pixserv_write(px, "OK\n");
+    if (pixserv_write(px, "OK\n")) goto close;
   }
 
   /* --- Request a passphrase --- */
@@ -728,13 +732,14 @@ OK\n\
       rc = p_get(&p, q, mode, t > timeout ? timeout : t);
       switch (rc) {
 	case 0:
-	  pixserv_write(px, "OK %s\n", p);
+	  if (pixserv_write(px, "OK %s\n", p)) goto close;
 	  break;
 	case -1:
-	  pixserv_write(px, "FAIL error reading passphrase\n");
+	  if (pixserv_write(px, "FAIL error reading passphrase\n"))
+	    goto close;
 	  break;
 	case +1:
-	  pixserv_write(px, "MISSING\n");
+	  if (pixserv_write(px, "MISSING\n")) goto close;
 	  break;
       }
     }
@@ -745,7 +750,7 @@ OK\n\
   else if (strcmp(q, "flush") == 0) {
     q = str_getword(&s);
     p_flush(q);
-    pixserv_write(px, "OK\n");
+    if (pixserv_write(px, "OK\n")) goto close;
   }
 
   /* --- Set a passphrase --- */
@@ -753,24 +758,25 @@ OK\n\
   else if (strcmp(q, "set") == 0) {
     char *tag;
     unsigned long t;
-    if ((tag = str_getword(&s)) == 0)
-      pixserv_write(px, "FAIL missing tag\n");
-    else if ((q = str_getword(&s)) == 0)
-      pixserv_write(px, "FAIL no passphrase\n");
-    else {
+    if ((tag = str_getword(&s)) == 0) {
+      if (pixserv_write(px, "FAIL missing tag\n")) goto close;
+    } else if ((q = str_getword(&s)) == 0) {
+      if (pixserv_write(px, "FAIL no passphrase\n")) goto close;
+    } else {
       if (strcmp(q, "--") != 0) {
 	t = pixserv_timeout(q);
 	q = str_getword(&s);
       } else
 	t = pixserv_timeout(0);
-      if (!q)
-	pixserv_write(px, "FAIL no passphrase\n");
-      else if (strcmp(q, "--") != 0)
-	pixserv_write(px, "FAIL rubbish found before passphrase\n");
-      else {
+      if (!q) {
+	if (pixserv_write(px, "FAIL no passphrase\n")) goto close;
+      } else if (strcmp(q, "--") != 0) {
+	if (pixserv_write(px, "FAIL rubbish found before passphrase\n"))
+	  goto close;
+      } else {
 	p_flush(tag);
 	p_add(tag, s, t);
-	pixserv_write(px, "OK\n");
+	if (pixserv_write(px, "OK\n")) goto close;
       }
     }
   }
@@ -778,17 +784,26 @@ OK\n\
   /* --- Shut the server down --- */
 
   else if (strcmp(q, "quit") == 0) {
-    if (verbose)
+    if (verbose) {
       pxlog("%s client requested shutdown",
 	    px->f & px_stdin ? "local" : "remote");
-    pixserv_write(px, "OK\n");
+    }
+    if (pixserv_write(px, "OK\n")) goto close;
     exit(0);
   }
 
   /* --- Report an error for other commands --- */
 
-  else
-    pixserv_write(px, "FAIL unknown command `%s'\n", q);
+  else {
+    if (pixserv_write(px, "FAIL unknown command `%s'\n", q)) goto close;
+  }
+  return;
+
+close:
+  if (px->fd != px->b.reader.fd)
+    close(px->fd);
+  selbuf_destroy(&px->b);
+  close(px->b.reader.fd);
 }
 
 /* --- @pixserv_create@ --- *
@@ -834,7 +849,7 @@ static void pixserv_accept(int fd, unsigned mode, void *p)
 {
   int nfd;
   struct sockaddr_un sun;
-  size_t sunsz = sizeof(sun);
+  socklen_t sunsz = sizeof(sun);
 
   if (mode != SEL_READ)
     return;
@@ -991,13 +1006,17 @@ static void pix_setup(struct sockaddr_un *sun, size_t sz)
 	  pxlog("stale socket found; removing it");
 	unlink(sun->sun_path);
 	close(fd);
-      } else {
+      } else if (flags & F_REPLACE) {
 	if (verbose)
 	  pxlog("server already running; shutting it down");
-	write(fd, "QUIT\n", 5);
+	if (write(fd, "QUIT\n", 5) < 0) {
+	  die(EXIT_FAILURE, "failed to shut down old server: %s",
+	      strerror(errno));
+	}
 	sleep(1);
 	close(fd);
-      }
+      } else
+	die(EXIT_FAILURE, "pixie already running; not starting");
       goto again;
     }
     chmod(sun->sun_path, 0600);
@@ -1038,7 +1057,8 @@ static void c_uline(char *s, size_t len, void *p)
     c_flags |= cf_uclose;
   } else {
     s[len++] = '\n';
-    write(c_server.reader.fd, s, len);
+    if (write(c_server.reader.fd, s, len) < 0)
+      die(EXIT_FAILURE, "failed to read from stdin: %s", strerror(errno));
   }
 }
 
@@ -1109,8 +1129,8 @@ static void pix_client(struct sockaddr_un *sun, size_t sz, char *argv[])
       DPUTS(&d, *argv++);
     }
     DPUTC(&d, '\n');
-    write(fd, d.buf, d.len);
-    shutdown(fd, 1);
+    if (write(fd, d.buf, d.len) < 0 || shutdown(fd, 1))
+      die(EXIT_FAILURE, "failed to write command: %s", strerror(errno));
     c_flags |= cf_uclose | cf_cooked;
     dstr_destroy(&d);
   }
@@ -1170,6 +1190,7 @@ protect important keys.  Options provided:\n\
 -q, --quiet		Emit fewer log messages.\n\
 -v, --version		Emit more log messages.\n\
 -s, --socket=FILE	Name the pixie's socket.\n\
+-r, --replace		Replace existing pixie, if one is running.\n\
 -c, --command=COMMAND	Shell command to read a passphrase.\n\
 -f, --fetch		Fetch passphrases from the terminal.\n\
 -t, --timeout=TIMEOUT	Length of time to retain a passphrase in memory.\n\
@@ -1244,6 +1265,7 @@ int main(int argc, char *argv[])
       { "passphrase",	0,		0,	'P' },
       { "verify-passphrase",	0,	0,	'+' },
       { "socket",	OPTF_ARGREQ,	0,	's' },
+      { "replace",	0,		0,	'r' },
       { "command",	OPTF_ARGREQ,	0,	'c' },
       { "fetch",	0,		0,	'f' },
       { "timeout",	OPTF_ARGREQ,	0,	't' },
@@ -1258,7 +1280,7 @@ int main(int argc, char *argv[])
       { 0,		0,		0,	0 }
     };
 
-    int i = mdwopt(argc, argv, "hVuqvCPs:c:ft:idl", opts, 0, 0, 0);
+    int i = mdwopt(argc, argv, "hVuqvCPs:rc:ft:idl", opts, 0, 0, 0);
     if (i < 0)
       break;
 
@@ -1302,6 +1324,9 @@ int main(int argc, char *argv[])
       case 's':
 	path = optarg;
 	break;
+      case 'r':
+	flags |= F_REPLACE;
+	break;
       case 't':
 	if ((timeout = pixserv_timeout(optarg)) == 0)
 	  die(1, "bad timeout `%s'", optarg);
@@ -1378,9 +1403,9 @@ int main(int argc, char *argv[])
     dstr d = DSTR_INIT;
     int rc = l_report(&lm, &d);
     if (rc < 0)
-      die(EXIT_FAILURE, d.buf);
+      die(EXIT_FAILURE, "%s", d.buf);
     else if (rc && verbose) {
-      pxlog(d.buf);
+      pxlog("%s", d.buf);
       pxlog("couldn't lock passphrase buffer");
     }
     dstr_destroy(&d);
@@ -1433,7 +1458,7 @@ int main(int argc, char *argv[])
       }
     }
 #endif
-    chdir("/");
+    DISCARD(chdir("/"));
     setsid();
 
     if (fork() != 0)