calculate and store checksum of xattrs

ref #3027

5 files changed, 63 insertions, 7 deletions

diff --git a/src/apk_database.h b/src/apk_database.h
index 880809b..b2fa28e 100644
--- a/src/apk_database.h
+++ b/src/apk_database.h
@@ -28,6 +28,7 @@ struct apk_db_acl {
 	mode_t mode;
 	uid_t uid;
 	gid_t gid;
+	struct apk_checksum xattr_csum;
 };
 
 struct apk_db_file {
diff --git a/src/apk_io.h b/src/apk_io.h
index 59a5d70..ee81851 100644
--- a/src/apk_io.h
+++ b/src/apk_io.h
@@ -45,6 +45,7 @@ struct apk_file_info {
 	time_t mtime;
 	dev_t device;
 	struct apk_checksum csum;
+	struct apk_checksum xattr_csum;
 	struct apk_xattr_array *xattrs;
 };
 
@@ -150,6 +151,7 @@ int apk_blob_to_file(int atfd, const char *file, apk_blob_t b, unsigned int flag
 #define APK_FI_NOFOLLOW		0x80000000
 int apk_fileinfo_get(int atfd, const char *filename, unsigned int flags,
 		     struct apk_file_info *fi);
+void apk_fileinfo_hash_xattr(struct apk_file_info *fi);
 void apk_fileinfo_free(struct apk_file_info *fi);
 
 typedef int apk_dir_file_cb(void *ctx, int dirfd, const char *entry);
diff --git a/src/archive.c b/src/archive.c
index 47b798b..3062c43 100644
--- a/src/archive.c
+++ b/src/archive.c
@@ -215,7 +215,10 @@ int apk_tar_parse(struct apk_istream *is, apk_archive_entry_parser parser,
 		teis.csum = NULL;
 		apk_xattr_array_resize(&entry.xattrs, 0);
 
-		if (paxlen) handle_extended_header(&entry, APK_BLOB_PTR_LEN(pax.ptr, paxlen));
+		if (paxlen) {
+			handle_extended_header(&entry, APK_BLOB_PTR_LEN(pax.ptr, paxlen));
+			apk_fileinfo_hash_xattr(&entry);
+		}
 
 		switch (buf.typeflag) {
 		case 'L': /* GNU long name extension */
diff --git a/src/database.c b/src/database.c
index bdf6d6b..8619465 100644
--- a/src/database.c
+++ b/src/database.c
@@ -220,10 +220,14 @@ struct apk_name *apk_db_get_name(struct apk_database *db, apk_blob_t name)
 	return pn;
 }
 
-static struct apk_db_acl *apk_db_acl_atomize(mode_t mode, uid_t uid, gid_t gid)
+static struct apk_db_acl *apk_db_acl_atomize(mode_t mode, uid_t uid, gid_t gid, const struct apk_checksum *xattr_csum)
 {
 	struct apk_db_acl acl = { .mode = mode & 07777, .uid = uid, .gid = gid };
 	apk_blob_t *b;
+
+	if (xattr_csum && xattr_csum->type != APK_CHECKSUM_NONE)
+		acl.xattr_csum = *xattr_csum;
+
 	b = apk_blob_atomize_dup(APK_BLOB_STRUCT(acl));
 	return (struct apk_db_acl *) b->ptr;
 }
@@ -740,6 +744,7 @@ int apk_db_index_read(struct apk_database *db, struct apk_bstream *bs, int repo)
 	struct apk_db_acl *acl;
 	struct hlist_node **diri_node = NULL;
 	struct hlist_node **file_diri_node = NULL;
+	struct apk_checksum xattr_csum;
 	apk_blob_t token = APK_BLOB_STR("\n"), l;
 	mode_t mode;
 	uid_t uid;
@@ -814,7 +819,12 @@ int apk_db_index_read(struct apk_database *db, struct apk_bstream *bs, int repo)
 			gid = apk_blob_pull_uint(&l, 10);
 			apk_blob_pull_char(&l, ':');
 			mode = apk_blob_pull_uint(&l, 8);
-			acl = apk_db_acl_atomize(mode, uid, gid);
+			if (apk_blob_pull_blob_match(&l, APK_BLOB_STR(":")))
+				apk_blob_pull_csum(&l, &xattr_csum);
+			else
+				xattr_csum.type = APK_CHECKSUM_NONE;
+
+			acl = apk_db_acl_atomize(mode, uid, gid, &xattr_csum);
 			if (field == 'M')
 				apk_db_diri_set(diri, acl);
 			else
@@ -877,6 +887,10 @@ static void apk_blob_push_db_acl(apk_blob_t *b, char field, struct apk_db_acl *a
 	apk_blob_push_uint(b, acl->gid, 10);
 	apk_blob_push_blob(b, APK_BLOB_STR(":"));
 	apk_blob_push_uint(b, acl->mode, 8);
+	if (acl->xattr_csum.type != APK_CHECKSUM_NONE) {
+		apk_blob_push_blob(b, APK_BLOB_STR(":"));
+		apk_blob_push_csum(b, &acl->xattr_csum);
+	}
 	apk_blob_push_blob(b, APK_BLOB_STR("\n"));
 }
 
@@ -1426,8 +1440,8 @@ int apk_db_open(struct apk_database *db, struct apk_db_options *dbopts)
 	apk_blob_t blob;
 	int r, fd, write_arch = FALSE;
 
-	apk_default_acl_dir = apk_db_acl_atomize(0755, 0, 0);
-	apk_default_acl_file = apk_db_acl_atomize(0644, 0, 0);
+	apk_default_acl_dir = apk_db_acl_atomize(0755, 0, 0, NULL);
+	apk_default_acl_file = apk_db_acl_atomize(0644, 0, 0, NULL);
 
 	memset(db, 0, sizeof(*db));
 	if (apk_flags & APK_SIMULATE) {
@@ -2346,7 +2360,7 @@ static int apk_db_install_archive_entry(void *_ctx,
 			apk_message("%s", ae->name);
 
 		/* Extract the file as name.apk-new */
-		file->acl = apk_db_acl_atomize(ae->mode, ae->uid, ae->gid);
+		file->acl = apk_db_acl_atomize(ae->mode, ae->uid, ae->gid, &ae->xattr_csum);
 		r = apk_archive_entry_extract(db->root_fd, ae, ".apk-new", is,
 					      extract_cb, ctx);
 
@@ -2388,7 +2402,7 @@ static int apk_db_install_archive_entry(void *_ctx,
 
 		diri = apk_db_install_directory_entry(ctx, name);
 		apk_db_dir_prepare(db, diri->dir, ae->mode);
-		apk_db_diri_set(diri, apk_db_acl_atomize(ae->mode, ae->uid, ae->gid));
+		apk_db_diri_set(diri, apk_db_acl_atomize(ae->mode, ae->uid, ae->gid, &ae->xattr_csum));
 	}
 	ctx->installed_size += ctx->current_file_size;
 
diff --git a/src/io.c b/src/io.c
index 2669ac3..8a23bb4 100644
--- a/src/io.c
+++ b/src/io.c
@@ -12,6 +12,7 @@
 #include <errno.h>
 #include <stdio.h>
 #include <fcntl.h>
+#include <endian.h>
 #include <unistd.h>
 #include <malloc.h>
 #include <dirent.h>
@@ -529,6 +530,41 @@ int apk_blob_to_file(int atfd, const char *file, apk_blob_t b, unsigned int flag
 	return r;
 }
 
+static int cmp_xattr(const void *p1, const void *p2)
+{
+	const struct apk_xattr *d1 = p1, *d2 = p2;
+	return strcmp(d1->name, d2->name);
+}
+
+static void hash_len_data(EVP_MD_CTX *ctx, uint32_t len, const void *ptr)
+{
+	uint32_t belen = htobe32(len);
+	EVP_DigestUpdate(ctx, &belen, sizeof(belen));
+	EVP_DigestUpdate(ctx, ptr, len);
+}
+
+void apk_fileinfo_hash_xattr(struct apk_file_info *fi)
+{
+	struct apk_xattr *xattr;
+	const EVP_MD *md = apk_checksum_default();
+	EVP_MD_CTX mdctx;
+
+	if (!fi->xattrs || fi->xattrs->num == 0) {
+		fi->xattr_csum.type = APK_CHECKSUM_NONE;
+		return;
+	}
+
+	qsort(fi->xattrs->item, fi->xattrs->num, sizeof(fi->xattrs->item[0]), cmp_xattr);
+
+	EVP_DigestInit(&mdctx, md);
+	foreach_array_item(xattr, fi->xattrs) {
+		hash_len_data(&mdctx, strlen(xattr->name), xattr->name);
+		hash_len_data(&mdctx, xattr->value.len, xattr->value.ptr);
+	}
+	fi->xattr_csum.type = EVP_MD_CTX_size(&mdctx);
+	EVP_DigestFinal(&mdctx, fi->xattr_csum.data, NULL);
+}
+
 int apk_fileinfo_get(int atfd, const char *filename, unsigned int flags,
 		     struct apk_file_info *fi)
 {