tar: support -T - and -X -

[oweals/busybox.git] / libbb / login.c

diff --git a/libbb/login.c b/libbb/login.c
index 646995b0bcc27cd938c4db78284f51b4510de11e..8a82c6add71041d8df959439053a0a6a621d6e31 100644 (file)
--- a/libbb/login.c
+++ b/libbb/login.c
@@ -6,25 +6,21 @@
  *
  * Optimize and correcting OCRNL by Vladimir Oleynik <dzo@simtreas.ru>
  *
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
 
-#include <sys/param.h>  /* MAXHOSTNAMELEN */
-#include <stdio.h>
-#include <unistd.h>
 #include "libbb.h"
-
+/* After libbb.h, since it needs sys/types.h on some systems */
 #include <sys/utsname.h>
-#include <time.h>
 
 #define LOGIN " login: "
 
-static const char fmtstr_d[] = "%A, %d %B %Y";
-static const char fmtstr_t[] = "%H:%M:%S";
+static const char fmtstr_d[] ALIGN1 = "%A, %d %B %Y";
+static const char fmtstr_t[] ALIGN1 = "%H:%M:%S";
 
-void print_login_issue(const char *issue_file, const char *tty)
+void FAST_FUNC print_login_issue(const char *issue_file, const char *tty)
 {
-       FILE *fd;
+       FILE *fp;
        int c;
        char buf[256+1];
        const char *outbuf;
@@ -34,85 +30,103 @@ void print_login_issue(const char *issue_file, const char *tty)
        time(&t);
        uname(&uts);
 
-       puts("\r");     /* start a new line */
-
-       if ((fd = fopen(issue_file, "r"))) {
-               while ((c = fgetc(fd)) != EOF) {
-                       outbuf = buf;
-                       buf[0] = c;
-                       if(c == '\n') {
-                               buf[1] = '\r';
-                               buf[2] = 0;
-                       } else {
-                               buf[1] = 0;
-                       }
-                       if (c == '\\' || c == '%') {
-                               c = fgetc(fd);
-                               switch (c) {
-                                       case 's':
-                                               outbuf = uts.sysname;
-                                               break;
-
-                                       case 'n':
-                                               outbuf = uts.nodename;
-                                               break;
-
-                                       case 'r':
-                                               outbuf = uts.release;
-                                               break;
-
-                                       case 'v':
-                                               outbuf = uts.version;
-                                               break;
-
-                                       case 'm':
-                                               outbuf = uts.machine;
-                                               break;
-
-                                       case 'D':
-                                       case 'o':
-                                               c = getdomainname(buf, sizeof(buf) - 1);
-                                               buf[c >= 0 ? c : 0] = '\0';
-                                               break;
-
-                                       case 'd':
-                                               strftime(buf, sizeof(buf), fmtstr_d, localtime(&t));
-                                               break;
-
-                                       case 't':
-                                               strftime(buf, sizeof(buf), fmtstr_t, localtime(&t));
-                                               break;
-
-                                       case 'h':
-                                               gethostname(buf, sizeof(buf) - 1);
-                                               buf[sizeof(buf) - 1] = '\0';
-                                               break;
-
-                                       case 'l':
-                                               outbuf = tty;
-                                               break;
-
-                                       default:
-                                               buf[0] = c;
-                               }
+       puts("\r");  /* start a new line */
+
+       fp = fopen_for_read(issue_file);
+       if (!fp)
+               return;
+       while ((c = fgetc(fp)) != EOF) {
+               outbuf = buf;
+               buf[0] = c;
+               buf[1] = '\0';
+               if (c == '\n') {
+                       buf[1] = '\r';
+                       buf[2] = '\0';
+               }
+               if (c == '\\' || c == '%') {
+                       c = fgetc(fp);
+                       switch (c) {
+                       case 's':
+                               outbuf = uts.sysname;
+                               break;
+                       case 'n':
+                       case 'h':
+                               outbuf = uts.nodename;
+                               break;
+                       case 'r':
+                               outbuf = uts.release;
+                               break;
+                       case 'v':
+                               outbuf = uts.version;
+                               break;
+                       case 'm':
+                               outbuf = uts.machine;
+                               break;
+/* The field domainname of struct utsname is Linux specific. */
+#if defined(__linux__)
+                       case 'D':
+                       case 'o':
+                               outbuf = uts.domainname;
+                               break;
+#endif
+                       case 'd':
+                               strftime(buf, sizeof(buf), fmtstr_d, localtime(&t));
+                               break;
+                       case 't':
+                               strftime(buf, sizeof(buf), fmtstr_t, localtime(&t));
+                               break;
+                       case 'l':
+                               outbuf = tty;
+                               break;
+                       default:
+                               buf[0] = c;
                        }
-                       fputs(outbuf, stdout);
                }
-
-               fclose(fd);
-
-               fflush(stdout);
+               fputs(outbuf, stdout);
        }
+       fclose(fp);
+       fflush_all();
 }
 
-void print_login_prompt(void)
+void FAST_FUNC print_login_prompt(void)
 {
-       char buf[MAXHOSTNAMELEN+1];
-
-       if(gethostname(buf, MAXHOSTNAMELEN) == 0)
-               fputs(buf, stdout);
+       char *hostname = safe_gethostname();
 
+       fputs(hostname, stdout);
        fputs(LOGIN, stdout);
-       fflush(stdout);
+       fflush_all();
+       free(hostname);
 }
 
+/* Clear dangerous stuff, set PATH */
+static const char forbid[] ALIGN1 =
+       "ENV" "\0"
+       "BASH_ENV" "\0"
+       "HOME" "\0"
+       "IFS" "\0"
+       "SHELL" "\0"
+       "LD_LIBRARY_PATH" "\0"
+       "LD_PRELOAD" "\0"
+       "LD_TRACE_LOADED_OBJECTS" "\0"
+       "LD_BIND_NOW" "\0"
+       "LD_AOUT_LIBRARY_PATH" "\0"
+       "LD_AOUT_PRELOAD" "\0"
+       "LD_NOWARN" "\0"
+       "LD_KEEPDIR" "\0";
+
+int FAST_FUNC sanitize_env_if_suid(void)
+{
+       const char *p;
+
+       if (getuid() == geteuid())
+               return 0;
+
+       p = forbid;
+       do {
+               unsetenv(p);
+               p += strlen(p) + 1;
+       } while (*p);
+       putenv((char*)bb_PATH_root_path);
+
+       return 1; /* we indeed were run by different user! */
+}