New option bits with el_torito_set_isolinux_options() and

iso_write_opts_set_system_area() to control GRUB2 patching of
boot image and MBR

libisofs/ecma119.c

@@ -3275,7 +3275,7 @@ int iso_write_opts_set_system_area(IsoWriteOpts *opts, char data[32768],
         memcpy(opts->system_area_data, data, 32768);
     }
     if (!(flag & 4))
-        opts->system_area_options = options & 0x3fff;
+        opts->system_area_options = options & 0x7fff;
     return ISO_SUCCESS;
 }
 

libisofs/eltorito.c

@@ -1,6 +1,6 @@
 /*
  * Copyright (c) 2007 Vreixo Formoso
- * Copyright (c) 2010 Thomas Schmitt
+ * Copyright (c) 2010 - 2013 Thomas Schmitt
  *
  * This file is part of the libisofs project; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License version 2 
@@ -160,7 +160,13 @@ int el_torito_get_selection_crit(ElToritoBootImage *bootimg, uint8_t crit[20])
 /* API */
 int el_torito_seems_boot_info_table(ElToritoBootImage *bootimg, int flag)
 {
-    return bootimg->seems_boot_info_table;
+    switch (flag & 15) {
+    case 0:
+        return bootimg->seems_boot_info_table;
+    case 1:
+        return bootimg->seems_grub2_boot_info;
+    }
+    return 0;
 }
 
 /**
@@ -197,14 +203,14 @@ void el_torito_patch_isolinux_image(ElToritoBootImage *bootimg)
  */
 int el_torito_set_isolinux_options(ElToritoBootImage *bootimg, int options, int flag)
 {
-    bootimg->isolinux_options = (options & 0x01ff);
+    bootimg->isolinux_options = (options & 0x03ff);
     return ISO_SUCCESS;
 }
 
 /* API */
 int el_torito_get_isolinux_options(ElToritoBootImage *bootimg, int flag)
 {
-    return bootimg->isolinux_options & 0x01ff;
+    return bootimg->isolinux_options & 0x03ff;
 }
 
 /* API */
@@ -1096,7 +1102,7 @@ int make_boot_info_table(uint8_t *buf, uint32_t pvd_lba,
 }
 
 /**
- * Patch an isolinux boot image.
+ * Patch an El Torito boot image by a boot info table.
  *
  * @return
  *      1 on success, 0 error (but continue), < 0 error
@@ -1117,6 +1123,27 @@ int patch_boot_info_table(uint8_t *buf, Ecma119Image *t,
     return ret;
 }
 
+
+/**
+ * Patch a GRUB2 El Torito boot image.
+ */
+static
+int patch_grub2_boot_image(uint8_t *buf, Ecma119Image *t,
+                           size_t imgsize, int idx,
+                           size_t pos, int offst)
+{
+    uint64_t blk;
+
+    if (imgsize < pos + 8)
+        return iso_msg_submit(t->image->id, ISO_ISOLINUX_CANT_PATCH, 0,
+                     "Isolinux image too small for GRUB2. Will not patch it.");
+    blk = ((uint64_t) t->bootsrc[idx]->sections[0].block) * 4 + offst;
+    iso_lsb((buf + pos), blk & 0xffffffff, 4);
+    iso_lsb((buf + pos + 4), blk >> 32, 4);
+    return ISO_SUCCESS;
+}
+
+
 /* Patch the boot images if indicated */
 int iso_patch_eltoritos(Ecma119Image *t)
 {
@@ -1130,7 +1157,7 @@ int iso_patch_eltoritos(Ecma119Image *t)
         return ISO_SUCCESS;
 
     for (idx = 0; idx < t->catalog->num_bootimages; idx++) {
-        if (!(t->catalog->bootimages[idx]->isolinux_options & 0x01))
+        if (!(t->catalog->bootimages[idx]->isolinux_options & 0x201))
     continue;
         original = t->bootsrc[idx]->stream;
         size = (size_t) iso_stream_get_size(original);
@@ -1154,9 +1181,20 @@ int iso_patch_eltoritos(Ecma119Image *t)
         }
 
         /* ok, patch the read buffer */
-        ret = patch_boot_info_table(buf, t, size, idx);
+        if (t->catalog->bootimages[idx]->isolinux_options & 0x200) {
-        if (ret < 0) {
+            /* GRUB2 boot provisions */
-            return ret;
+            ret = patch_grub2_boot_image(buf, t, size, idx,
+                                         Libisofs_grub2_elto_patch_poS,
+                                         Libisofs_grub2_elto_patch_offsT);
+            if (ret < 0)
+                return ret;
+	}
+        /* Must be done as last patching */
+        if (t->catalog->bootimages[idx]->isolinux_options & 0x01) {
+            /* Boot Info Table */
+            ret = patch_boot_info_table(buf, t, size, idx);
+            if (ret < 0)
+                return ret;
         }
 
         /* replace the original stream with a memory stream that reads from

libisofs/eltorito.h

@@ -58,6 +58,7 @@ struct el_torito_boot_image {
      * Whether the boot image seems to contain a boot_info_table
      */
     unsigned int seems_boot_info_table:1;
+    unsigned int seems_grub2_boot_info:1;
     /**
      * isolinux options
      * bit 0 -> whether to patch image
@@ -155,4 +156,12 @@ int make_boot_info_table(uint8_t *buf, uint32_t pvd_lba,
 */
 int iso_patch_eltoritos(Ecma119Image *t);
 
+
+/* Parameters for patch_grub2_boot_image()
+   Might later become variables in struct el_torito_boot_image.
+*/
+#define Libisofs_grub2_elto_patch_poS    (512 * 5 - 12)
+#define Libisofs_grub2_elto_patch_offsT  5
+
+
 #endif /* LIBISO_ELTORITO_H */

libisofs/fs_image.c

@@ -3375,13 +3375,14 @@ static
 int iso_image_eval_boot_info_table(IsoImage *image, struct iso_read_opts *opts,
                          IsoDataSource *src, uint32_t iso_image_size, int flag)
 {
-    int i, ret, section_count, todo, chunk;
+    int i, j, ret, section_count, todo, chunk;
     uint32_t img_lba, img_size, boot_pvd_found, image_pvd, alleged_size;
     struct iso_file_section *sections = NULL;
     struct el_torito_boot_image *boot;
     uint8_t *boot_image_buf = NULL, boot_info_found[16], *buf = NULL;
     IsoStream *stream = NULL;
     IsoFile *boot_file;
+    uint64_t blk;
 
     if (image->bootcat == NULL)
         {ret = ISO_SUCCESS; goto ex;}
@@ -3390,6 +3391,7 @@ int iso_image_eval_boot_info_table(IsoImage *image, struct iso_read_opts *opts,
         boot = image->bootcat->bootimages[i];
         boot_file = boot->image;
         boot->seems_boot_info_table = 0;
+        boot->seems_grub2_boot_info = 0;
         img_size = iso_file_get_size(boot_file);
         if (img_size > Libisofs_boot_image_max_sizE || img_size < 64)
     continue;
@@ -3455,6 +3457,16 @@ int iso_image_eval_boot_info_table(IsoImage *image, struct iso_read_opts *opts,
             goto ex;
         if (memcmp(boot_image_buf + 8, boot_info_found, 16) == 0)
             boot->seems_boot_info_table = 1;
+
+        if (img_size >= Libisofs_grub2_elto_patch_poS + 8) {
+            blk = 0;
+            for (j = Libisofs_grub2_elto_patch_poS + 7;
+                 j >= Libisofs_grub2_elto_patch_poS; j--)
+                blk = (blk << 8) | boot_image_buf[j];
+            if (blk == img_lba * 4 + Libisofs_grub2_elto_patch_offsT)
+                boot->seems_grub2_boot_info = 1;
+        }
+
         free(boot_image_buf);
         boot_image_buf = NULL;
     }

libisofs/libisofs.h

@@ -2191,6 +2191,13 @@ int iso_write_opts_set_fifo_size(IsoWriteOpts *opts, size_t fifo_size);
  *                1 = CHRP: A single MBR partition of type 0x96 covers the
  *                          ISO image. Not compatible with any other feature
  *                          which needs to have own MBR partition entries.
+ *        bit14= Only with System area type 0 = MBR
+ *              GRUB2 boot provisions:
+ *              @since 1.3.0
+ *              Patch system area at byte 92 to 99 with 512-block address + 1
+ *              of the first boot image file. Little-endian 8-byte.
+ *              Should be combined with options bit0.
+ *              Will not be in effect if options bit1 is set.
  * @param flag
  *        bit0 = invalidate any attached system area data. Same as data == NULL
  *               (This re-activates eventually loaded image System Area data.
@@ -3465,9 +3472,15 @@ int el_torito_get_selection_crit(ElToritoBootImage *bootimg, uint8_t crit[20]);
  * @param bootimg
  *      The image to inquire
  * @param flag
- *        Reserved for future usage, set to 0.
+ *       Bitfield for control purposes:
+ *       bit0 - bit3= mode
+ *       0 = inquire for classic boot info table as described in man mkisofs
+ *           @since 0.6.32
+ *       1 = inquire for GRUB2 boot info as of bit9 of options of
+ *           el_torito_set_isolinux_options()
+ *           @since 1.3.0
  * @return
- *      1 = seems to contain oot info table , 0 = quite surely not
+ *      1 = seems to contain the inquired boot info, 0 = quite surely not
  * @since 0.6.32
  */
 int el_torito_seems_boot_info_table(ElToritoBootImage *bootimg, int flag);
@@ -3531,6 +3544,11 @@ int el_torito_seems_boot_info_table(ElToritoBootImage *bootimg, int flag);
  *              mentioned. The ISOLINUX MBR must look suitable or else an error
  *              event will happen at image generation time.
  *              @since 1.2.4
+ *        bit9= GRUB2 boot info
+ *              Patch the boot image file at byte 1012 with the 512-block
+ *              address + 2. Two little endian 32-bit words. Low word first.
+ *              This is combinable with bit0.
+ *              @since 1.3.0
  * @param flag
  *        Reserved for future usage, set to 0.
  * @return

libisofs/system_area.c

@@ -1,6 +1,6 @@
 /*
  * Copyright (c) 2008 Vreixo Formoso
- * Copyright (c) 2010 - 2012 Thomas Schmitt
+ * Copyright (c) 2010 - 2013 Thomas Schmitt
  *
  * This file is part of the libisofs project; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License version 2 
@@ -1417,6 +1417,8 @@ int iso_write_system_area(Ecma119Image *t, uint8_t *buf)
     int first_partition = 1, last_partition = 4, apm_flag, part_type;
     int gpt_count = 0, gpt_idx[128], apm_count = 0;
     uint32_t img_blocks;
+    uint64_t blk;
+    uint8_t *wpt;
 
     if ((t == NULL) || (buf == NULL)) {
         return ISO_NULL_POINTER;
@@ -1607,6 +1609,15 @@ int iso_write_system_area(Ecma119Image *t, uint8_t *buf)
             return ret;
     }
 
+    if (sa_type == 0 && (t->system_area_options & 0x4000) && !do_isohybrid) {
+        /* Patch MBR for GRUB2 */
+        blk = t->bootsrc[0]->sections[0].block * 4 +
+                                                Libisofs_grub2_mbr_patch_offsT;
+        wpt = buf + Libisofs_grub2_mbr_patch_poS;
+        for (i = 0; i < 8; i++)
+             wpt[i] = blk >> (i * 8);
+    }
+
     return ISO_SUCCESS;
 }
 

libisofs/system_area.h

@@ -266,4 +266,11 @@ int gpt_tail_writer_create(Ecma119Image *target);
 /* Only for up to 36 characters ISO-8859-1 (or ASCII) input */
 void iso_ascii_utf_16le(uint8_t gap_name[72]);
 
+
+/* Parameters of MBR patching for GRUB2
+   Might later become variables in Ecma119Image
+*/
+#define Libisofs_grub2_mbr_patch_poS    0x1b0
+#define Libisofs_grub2_mbr_patch_offsT      3
+
 #endif /* SYSTEM_AREA_H_ */