5 files changed, 115 insertions, 0 deletions

diff --git a/lib/tar/Makemodule.am b/lib/tar/Makemodule.am
index a47b07a..fe18895 100644
--- a/lib/tar/Makemodule.am
+++ b/lib/tar/Makemodule.am
@@ -4,6 +4,7 @@ libtar_a_SOURCES += lib/tar/read_sparse_map.c lib/tar/read_sparse_map_old.c
 libtar_a_SOURCES += lib/tar/base64.c lib/tar/urldecode.c lib/tar/internal.h
 libtar_a_SOURCES += lib/tar/padd_file.c lib/tar/read_retry.c include/tar.h
 libtar_a_SOURCES += lib/tar/write_retry.c lib/tar/pax_header.c
+libtar_a_SOURCES += lib/tar/read_sparse_map_new.c
 libtar_a_CFLAGS = $(AM_CFLAGS)
 libtar_a_CPPFLAGS = $(AM_CPPFLAGS)
 
diff --git a/lib/tar/internal.h b/lib/tar/internal.h
index e79596b..65e5d45 100644
--- a/lib/tar/internal.h
+++ b/lib/tar/internal.h
@@ -27,6 +27,8 @@ enum {
 	PAX_SLINK_TARGET = 0x040,
 	PAX_MTIME = 0x100,
 	PAX_SPARSE_SIZE = 0x400,
+
+	PAX_SPARSE_GNU_1_X = 0x800,
 };
 
 enum {
@@ -58,6 +60,8 @@ sparse_map_t *read_sparse_map(const char *line);
 
 sparse_map_t *read_gnu_old_sparse(FILE *fp, tar_header_t *hdr);
 
+sparse_map_t *read_gnu_new_sparse(FILE *fp, tar_header_decoded_t *out);
+
 void free_sparse_list(sparse_map_t *sparse);
 
 size_t base64_decode(sqfs_u8 *out, const char *in, size_t len);
diff --git a/lib/tar/pax_header.c b/lib/tar/pax_header.c
index 4eeabf5..448976d 100644
--- a/lib/tar/pax_header.c
+++ b/lib/tar/pax_header.c
@@ -110,6 +110,13 @@ int read_pax_header(FILE *fp, sqfs_u64 entsize, unsigned int *set_by_pax,
 			if (pax_read_decimal(ptr + 16, &out->actual_size))
 				goto fail;
 			*set_by_pax |= PAX_SPARSE_SIZE;
+		} else if (!strncmp(ptr, "GNU.sparse.realsize=", 20)) {
+			if (pax_read_decimal(ptr + 20, &out->actual_size))
+				goto fail;
+			*set_by_pax |= PAX_SPARSE_SIZE;
+		} else if (!strncmp(ptr, "GNU.sparse.major=", 17) ||
+			   !strncmp(ptr, "GNU.sparse.minor=", 17)) {
+			*set_by_pax |= PAX_SPARSE_GNU_1_X;
 		} else if (!strncmp(ptr, "GNU.sparse.offset=", 18)) {
 			if (pax_read_decimal(ptr + 18, &offset))
 				goto fail;
diff --git a/lib/tar/read_header.c b/lib/tar/read_header.c
index e8e49c2..14752ea 100644
--- a/lib/tar/read_header.c
+++ b/lib/tar/read_header.c
@@ -255,6 +255,13 @@ int read_header(FILE *fp, tar_header_decoded_t *out)
 	if (decode_header(&hdr, set_by_pax, out, version))
 		goto fail;
 
+	if (set_by_pax & PAX_SPARSE_GNU_1_X) {
+		free_sparse_list(out->sparse);
+		out->sparse = read_gnu_new_sparse(fp, out);
+		if (out->sparse == NULL)
+			goto fail;
+	}
+
 	if (out->sparse != NULL) {
 		out->sb.st_size = out->actual_size;
 	} else {
diff --git a/lib/tar/read_sparse_map_new.c b/lib/tar/read_sparse_map_new.c
new file mode 100644
index 0000000..246f8a5
--- /dev/null
+++ b/lib/tar/read_sparse_map_new.c
@@ -0,0 +1,96 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * read_sparse_map_new.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "config.h"
+
+#include "internal.h"
+
+static int decode(const char *str, size_t len, size_t *out)
+{
+	size_t count = 0;
+
+	*out = 0;
+
+	while (count < len && isdigit(*str)) {
+		if (*out > 0xFFFFFFFFFFFFFFFFUL / 10)
+			return -1;
+		*out = (*out) * 10 + (*(str++) - '0');
+		++count;
+	}
+
+	if (count == 0 || count == len)
+		return 0;
+
+	return (*str == '\n') ? ((int)count + 1) : -1;
+}
+
+sparse_map_t *read_gnu_new_sparse(FILE *fp, tar_header_decoded_t *out)
+{
+	sparse_map_t *last = NULL, *list = NULL, *ent = NULL;
+	size_t i, count, value;
+	char buffer[1024];
+	int diff, ret;
+
+	if (read_retry("reading GNU sparse map", fp, buffer, 512))
+		return NULL;
+
+	diff = decode(buffer, 512, &count);
+	if (diff <= 0)
+		goto fail_format;
+
+	out->record_size -= 512;
+
+	for (i = 0; i < (count * 2); ++i) {
+		ret = decode(buffer + diff, 512 - diff, &value);
+		if (ret < 0)
+			goto fail_format;
+
+		if (ret > 0) {
+			diff += ret;
+		} else {
+			if (read_retry("reading GNU sparse map", fp,
+				       buffer + 512, 512)) {
+				return NULL;
+			}
+
+			ret = decode(buffer + diff, 1024 - diff, &value);
+			if (ret <= 0)
+				goto fail_format;
+
+			memcpy(buffer, buffer + 512, 512);
+			diff = diff + ret - 512;
+			out->record_size -= 512;
+		}
+
+		if ((i & 0x01) == 0) {
+			ent = calloc(1, sizeof(*ent));
+			if (ent == NULL)
+				goto fail_errno;
+
+			if (list == NULL) {
+				list = last = ent;
+			} else {
+				last->next = ent;
+				last = ent;
+			}
+
+			ent->offset = value;
+		} else {
+			ent->count = value;
+		}
+	}
+
+	return list;
+fail_errno:
+	perror("parsing GNU 1.0 style sparse file record");
+	goto fail;
+fail_format:
+	fputs("Malformed GNU 1.0 style sparse file map.\n", stderr);
+	goto fail;
+fail:
+	free_sparse_list(list);
+	return NULL;
+}