Changeset 2725 in MondoRescue for branches/2.2.9/mindi-busybox/util-linux/mkswap.c

Timestamp:

Feb 25, 2011, 9:26:54 PM (13 years ago)

Author:

Bruno Cornec

Message:

• Update mindi-busybox to 1.18.3 to avoid problems with the tar command which is now failing on recent versions with busybox 1.7.3

File:

• branches/2.2.9/mindi-busybox/util-linux/mkswap.c (modified) (1 diff)

branches/2.2.9/mindi-busybox/util-linux/mkswap.c

@@ -4 +4 @@
  * Copyright 2006 Rob Landley <rob@landley.net>
  *
- * Licensed under GPL version 2, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2, see file LICENSE in this source tree.
  */
-
 #include "libbb.h"
 
-int mkswap_main(int argc, char **argv);
-int mkswap_main(int argc, char **argv)
+#if ENABLE_SELINUX
+static void mkswap_selinux_setcontext(int fd, const char *path)
 {
-    int fd, pagesize;
+    struct stat stbuf;
+
+    if (!is_selinux_enabled())
+        return;
+
+    xfstat(fd, &stbuf, path);
+    if (S_ISREG(stbuf.st_mode)) {
+        security_context_t newcon;
+        security_context_t oldcon = NULL;
+        context_t context;
+
+        if (fgetfilecon(fd, &oldcon) < 0) {
+            if (errno != ENODATA)
+                goto error;
+            if (matchpathcon(path, stbuf.st_mode, &oldcon) < 0)
+                goto error;
+        }
+        context = context_new(oldcon);
+        if (!context || context_type_set(context, "swapfile_t"))
+            goto error;
+        newcon = context_str(context);
+        if (!newcon)
+            goto error;
+        /* fsetfilecon_raw is hidden */
+        if (strcmp(oldcon, newcon) != 0 && fsetfilecon(fd, newcon) < 0)
+            goto error;
+        if (ENABLE_FEATURE_CLEAN_UP) {
+            context_free(context);
+            freecon(oldcon);
+        }
+    }
+    return;
+ error:
+    bb_perror_msg_and_die("SELinux relabeling failed");
+}
+#else
+# define mkswap_selinux_setcontext(fd, path) ((void)0)
+#endif
+
+/* from Linux 2.6.23 */
+/*
+ * Magic header for a swap area. ... Note that the first
+ * kilobyte is reserved for boot loader or disk label stuff.
+ */
+struct swap_header_v1 {
+/*  char     bootbits[1024];    Space for disklabel etc. */
+    uint32_t version;        /* second kbyte, word 0 */
+    uint32_t last_page;      /* 1 */
+    uint32_t nr_badpages;    /* 2 */
+    char     sws_uuid[16];   /* 3,4,5,6 */
+    char     sws_volume[16]; /* 7,8,9,10 */
+    uint32_t padding[117];   /* 11..127 */
+    uint32_t badpages[1];    /* 128 */
+    /* total 129 32-bit words in 2nd kilobyte */
+} FIX_ALIASING;
+
+#define NWORDS 129
+#define hdr ((struct swap_header_v1*)bb_common_bufsiz1)
+
+struct BUG_sizes {
+    char swap_header_v1_wrong[sizeof(*hdr)  != (NWORDS * 4) ? -1 : 1];
+    char bufsiz1_is_too_small[COMMON_BUFSIZE < (NWORDS * 4) ? -1 : 1];
+};
+
+/* Stored without terminating NUL */
+static const char SWAPSPACE2[sizeof("SWAPSPACE2")-1] ALIGN1 = "SWAPSPACE2";
+
+int mkswap_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int mkswap_main(int argc UNUSED_PARAM, char **argv)
+{
+    int fd;
+    unsigned pagesize;
     off_t len;
-    unsigned int hdr[129];
+    const char *label = "";
 
-    // No options supported.
+    opt_complementary = "-1"; /* at least one param */
+    /* TODO: -p PAGESZ, -U UUID */
+    getopt32(argv, "L:", &label);
+    argv += optind;
 
-    if (argc != 2) bb_show_usage();
+    fd = xopen(argv[0], O_WRONLY);
 
-    // Figure out how big the device is and announce our intentions.
+    /* Figure out how big the device is */
+    len = get_volume_size_in_bytes(fd, argv[1], 1024, /*extend:*/ 1);
+    pagesize = getpagesize();
+    len -= pagesize;
 
-    fd = xopen(argv[1], O_RDWR);
-    len = fdlength(fd);
-    pagesize = getpagesize();
-    printf("Setting up swapspace version 1, size = %"OFF_FMT"d bytes\n",
-            len - pagesize);
+    /* Announce our intentions */
+    printf("Setting up swapspace version 1, size = %"OFF_FMT"u bytes\n", len);
+    mkswap_selinux_setcontext(fd, argv[0]);
 
-    // Make a header.
+    /* hdr is zero-filled so far. Clear the first kbyte, or else
+     * mkswap-ing former FAT partition does NOT erase its signature.
+     *
+     * util-linux-ng 2.17.2 claims to erase it only if it does not see
+     * a partition table and is not run on whole disk. -f forces it.
+     */
+    xwrite(fd, hdr, 1024);
 
-    memset(hdr, 0, sizeof(hdr));
-    hdr[0] = 1;
-    hdr[1] = (len / pagesize) - 1;
+    /* Fill the header. */
+    hdr->version = 1;
+    hdr->last_page = (uoff_t)len / pagesize;
 
-    // Write the header.  Sync to disk because some kernel versions check
-    // signature on disk (not in cache) during swapon.
+    if (ENABLE_FEATURE_MKSWAP_UUID) {
+        char uuid_string[32];
+        generate_uuid((void*)hdr->sws_uuid);
+        bin2hex(uuid_string, hdr->sws_uuid, 16);
+        /* f.e. UUID=dfd9c173-be52-4d27-99a5-c34c6c2ff55f */
+        printf("UUID=%.8s"  "-%.4s-%.4s-%.4s-%.12s\n",
+            uuid_string,
+            uuid_string+8,
+            uuid_string+8+4,
+            uuid_string+8+4+4,
+            uuid_string+8+4+4+4
+        );
+    }
+    safe_strncpy(hdr->sws_volume, label, 16);
 
-    xlseek(fd, 1024, SEEK_SET);
-    xwrite(fd, hdr, sizeof(hdr));
-    xlseek(fd, pagesize-10, SEEK_SET);
-    xwrite(fd, "SWAPSPACE2", 10);
+    /* Write the header.  Sync to disk because some kernel versions check
+     * signature on disk (not in cache) during swapon. */
+    xwrite(fd, hdr, NWORDS * 4);
+    xlseek(fd, pagesize - 10, SEEK_SET);
+    xwrite(fd, SWAPSPACE2, 10);
     fsync(fd);
 
-    if (ENABLE_FEATURE_CLEAN_UP) close(fd);
+    if (ENABLE_FEATURE_CLEAN_UP)
+        close(fd);
 
     return 0;