libblkid: Expose more ISO9660 headers

In order to kill libosinfo's infamous udev rule[1], we need to make blkid
report the following information as udev properties on IS09660 media so
that libosinfo can make use of that for detection:

1. Volume ID (already exposed as label).
2. System ID.
3. Publisher ID.
4. Application ID.
5. Boot record's boot system ID, (almost always 'EL TORITO
   SPECIFICATION' if boot record is present).

Example use:

$ blkid -p -o udev Fedora-17-x86_64-DVD.iso
ID_FS_SYSTEM_ID=LINUX
ID_FS_APPLICATION_ID=GENISOIMAGE ISO 9660/HFS FILESYSTEM CREATOR (C)
1993 E.YOUNGDALE
ID_FS_UUID=2012-05-22-20-55-32-00
ID_FS_UUID_ENC=2012-05-22-20-55-32-00
ID_FS_BOOT_SYSTEM_ID=EL TORITO SPECIFICATION
ID_FS_LABEL=Fedora_17_x86_64
ID_FS_LABEL_ENC=Fedora\x2017\x20x86_64
ID_FS_TYPE=iso9660
ID_PART_TABLE_TYPE=dos

[1] https://fedorahosted.org/libosinfo/ticket/1

[kzak@redhat.com: - add blkid_ltrim_whitespace() and use it together
                    with blkid_rtrim_whitespace() to trim white spaces
                  - enlarge blkid values to 128 bytes
                  - add generic blkid_probe_set_id_label() function
                  - always terminate all _ID with \0
                  - don't export the _IDs to blkid cache]

Signed-off-by: Karel Zak <kzak@redhat.com>

3 files changed, 100 insertions, 5 deletions

diff --git a/libblkid/src/superblocks/iso9660.c b/libblkid/src/superblocks/iso9660.c
index 33a8597ed..ad7bf3de1 100644
--- a/libblkid/src/superblocks/iso9660.c
+++ b/libblkid/src/superblocks/iso9660.c
@@ -16,6 +16,7 @@
 #include <unistd.h>
 #include <string.h>
 #include <stdint.h>
+#include <ctype.h>
 
 #include "superblocks.h"
 
@@ -41,14 +42,29 @@ struct iso_volume_descriptor {
 	unsigned char	unused[8];
 	unsigned char	space_size[8];
 	unsigned char	escape_sequences[8];
-	unsigned char   unused1[717];
+	unsigned char  unused1[222];
+	unsigned char  publisher_id[128];
+	unsigned char  unused2[128];
+	unsigned char  application_id[128];
+	unsigned char  unused3[111];
 	struct iso9660_date created;
 	struct iso9660_date modified;
 } __attribute__((packed));
 
+/* Boot Record */
+struct boot_record {
+	unsigned char	vd_type;
+	unsigned char	vd_id[5];
+	unsigned char	vd_version;
+	unsigned char	boot_system_id[32];
+	unsigned char	boot_id[32];
+	unsigned char	unused[1];
+} __attribute__((packed));
+
 #define ISO_SUPERBLOCK_OFFSET		0x8000
 #define ISO_SECTOR_SIZE			0x800
 #define ISO_VD_OFFSET			(ISO_SUPERBLOCK_OFFSET + ISO_SECTOR_SIZE)
+#define ISO_VD_BOOT_RECORD		0x0
 #define ISO_VD_SUPPLEMENTARY		0x2
 #define ISO_VD_END			0xff
 #define ISO_VD_MAX			16
@@ -136,6 +152,19 @@ static int probe_iso9660_set_uuid (blkid_probe pr, const struct iso9660_date *da
 	return 1;
 }
 
+static int is_str_empty(const unsigned char *str, size_t len)
+{
+	size_t i;
+
+	if (!str || !*str)
+		return 1;
+
+	for (i = 0; i < len; i++)
+		if (!isspace(str[i]))
+			return 0;
+	return 1;
+}
+
 /* iso9660 [+ Microsoft Joliet Extension] */
 static int probe_iso9660(blkid_probe pr, const struct blkid_idmag *mag)
 {
@@ -153,20 +182,46 @@ static int probe_iso9660(blkid_probe pr, const struct blkid_idmag *mag)
 
 	memcpy(label, iso->volume_id, sizeof(label));
 
+	if (!is_str_empty(iso->system_id, sizeof(iso->system_id)))
+		blkid_probe_set_id_label(pr, "SYSTEM_ID",
+				iso->system_id, sizeof(iso->system_id));
+
+	if (!is_str_empty(iso->publisher_id, sizeof(iso->publisher_id)))
+		blkid_probe_set_id_label(pr, "PUBLISHER_ID",
+				iso->publisher_id, sizeof(iso->publisher_id));
+
+	if (!is_str_empty(iso->application_id, sizeof(iso->application_id)))
+		blkid_probe_set_id_label(pr, "APPLICATION_ID",
+				iso->application_id, sizeof(iso->application_id));
+
 	/* create an UUID using the modified/created date */
 	if (! probe_iso9660_set_uuid(pr, &iso->modified))
 		probe_iso9660_set_uuid(pr, &iso->created);
 
-	/* Joliet Extension */
+	/* Joliet Extension and Boot Record */
 	off = ISO_VD_OFFSET;
 	for (i = 0; i < ISO_VD_MAX; i++) {
-		iso = (struct iso_volume_descriptor *)
+		struct boot_record *boot= (struct boot_record *)
 			blkid_probe_get_buffer(pr,
 					off,
-					sizeof(struct iso_volume_descriptor));
+					sizeof(struct boot_record));
 
-		if (iso == NULL || iso->vd_type == ISO_VD_END)
+		if (boot == NULL || boot->vd_type == ISO_VD_END)
 			break;
+
+		if (boot->vd_type == ISO_VD_BOOT_RECORD) {
+			if (!is_str_empty(boot->boot_system_id,
+					  sizeof(boot->boot_system_id)))
+				blkid_probe_set_id_label(pr, "BOOT_SYSTEM_ID",
+							boot->boot_system_id,
+							sizeof(boot->boot_system_id));
+			off += ISO_SECTOR_SIZE;
+			continue;
+		}
+
+		/* Not a Boot record, lets see if its supplemntary volume descriptor */
+		iso = (struct iso_volume_descriptor *) boot;
+
 		if (iso->vd_type != ISO_VD_SUPPLEMENTARY) {
 			off += ISO_SECTOR_SIZE;
 			continue;
diff --git a/libblkid/src/superblocks/superblocks.c b/libblkid/src/superblocks/superblocks.c
index 62aa6625b..384d2cad7 100644
--- a/libblkid/src/superblocks/superblocks.c
+++ b/libblkid/src/superblocks/superblocks.c
@@ -64,6 +64,14 @@
  * @SBMAGIC_OFFSET: offset of SBMAGIC
  *
  * @FSSIZE: size of filessystem [not-implemented yet]
+ *
+ * @SYSTEM_ID: ISO9660 system identifier
+ *
+ * @PUBLISHER_ID: ISO9660 publisher identifier
+ *
+ * @APPLICATION_ID: ISO9660 application identifier
+ *
+ * @BOOT_SYSTEM_ID: ISO9660 boot system identifier
  */
 
 static int superblocks_probe(blkid_probe pr, struct blkid_chain *chn);
@@ -495,6 +503,7 @@ int blkid_probe_set_version(blkid_probe pr, const char *version)
 	return 0;
 }
 
+
 int blkid_probe_sprintf_version(blkid_probe pr, const char *fmt, ...)
 {
 	struct blkid_chain *chn = blkid_probe_get_chain(pr);
@@ -532,6 +541,35 @@ static int blkid_probe_set_usage(blkid_probe pr, int usage)
 	return blkid_probe_set_value(pr, "USAGE", (unsigned char *) u, strlen(u) + 1);
 }
 
+int blkid_probe_set_id_label(blkid_probe pr, const char *name,
+			     unsigned char *data, size_t len)
+{
+	struct blkid_chain *chn = blkid_probe_get_chain(pr);
+	struct blkid_prval *v;
+
+	if (!(chn->flags & BLKID_SUBLKS_LABEL))
+		return 0;
+
+	v = blkid_probe_assign_value(pr, name);
+	if (!v)
+		return -1;
+
+	if (len >= BLKID_PROBVAL_BUFSIZ)
+		len = BLKID_PROBVAL_BUFSIZ - 1;			/* make a space for \0 */
+
+	memcpy(v->data, data, len);
+	v->data[len] = '\0';
+
+	/* remove white spaces */
+	v->len = blkid_rtrim_whitespace(v->data) + 1;
+	if (v->len > 1)
+		v->len = blkid_ltrim_whitespace(v->data) + 1;
+
+	if (v->len <= 1)
+		blkid_probe_reset_last_value(pr);		/* ignore empty */
+	return 0;
+}
+
 int blkid_probe_set_label(blkid_probe pr, unsigned char *label, size_t len)
 {
 	struct blkid_chain *chn = blkid_probe_get_chain(pr);
diff --git a/libblkid/src/superblocks/superblocks.h b/libblkid/src/superblocks/superblocks.h
index 887732a73..e45dc6a84 100644
--- a/libblkid/src/superblocks/superblocks.h
+++ b/libblkid/src/superblocks/superblocks.h
@@ -89,5 +89,7 @@ extern int blkid_probe_strncpy_uuid(blkid_probe pr, unsigned char *str, size_t l
 extern int blkid_probe_set_uuid(blkid_probe pr, unsigned char *uuid);
 extern int blkid_probe_set_uuid_as(blkid_probe pr, unsigned char *uuid, const char *name);
 
+extern int blkid_probe_set_id_label(blkid_probe pr, const char *name,
+			     unsigned char *data, size_t len);
 
 #endif /* _BLKID_SUPERBLOCKS_H */