archive: honor username/groupname instead of uid/gid

Take the uid/gid from passwd and group.

src/apk.c

@@ -244,6 +244,7 @@ int main(int argc, char **argv)
 	memset(&dbopts, 0, sizeof(dbopts));
 	list_init(&dbopts.repository_list);
 	umask(0);
+	apk_id_cache_init();
 
 	applet = deduce_applet(argc, argv);
 	num_options = ARRAY_SIZE(generic_options) + 1;
@@ -365,6 +366,7 @@ int main(int argc, char **argv)
 
 	r = applet->main(ctx, &db, argc, argv);
 	apk_db_close(&db);
+	apk_id_cache_free();
 
 	if (r == -EINVAL)
 		return usage(applet);

src/apk_io.h

@@ -95,4 +95,10 @@ int apk_file_get_info(int atfd, const char *filename, unsigned int flags,
 int apk_url_download(const char *url, int atfd, const char *file);
 const char *apk_url_local_file(const char *url);
 
+void apk_id_cache_init(void);
+void apk_id_cache_free(void);
+void apk_id_cache_reset(void);
+uid_t apk_resolve_uid(const char *username, uid_t default_uid);
+uid_t apk_resolve_gid(const char *groupname, uid_t default_gid);
+
 #endif

src/archive.c

@@ -388,7 +388,10 @@ int apk_archive_entry_extract(int atfd, const struct apk_file_info *ae,
 		break;
 	}
 	if (r == 0) {
-		r = fchownat(atfd, fn, ae->uid, ae->gid, atflags);
+		r = fchownat(atfd, fn,
+			     apk_resolve_uid(ae->uname, ae->uid),
+			     apk_resolve_gid(ae->gname, ae->gid),
+			     atflags);
 		if (r < 0) {
 			apk_error("Failed to set ownership on %s: %s",
 				  fn, strerror(errno));

src/io.c

@@ -15,9 +15,12 @@
 #include <unistd.h>
 #include <malloc.h>
 #include <sys/mman.h>
+#include <pwd.h>
+#include <grp.h>
 
 #include "apk_defines.h"
 #include "apk_io.h"
+#include "apk_hash.h"
 
 struct apk_fd_istream {
 	struct apk_istream is;
@@ -715,3 +718,126 @@ size_t apk_ostream_write_string(struct apk_ostream *os, const char *string)
 
 	return len;
 }
+
+struct cache_item {
+	apk_hash_node hash_node;
+	unsigned int genid;
+	union {
+		uid_t uid;
+		gid_t gid;
+	};
+	unsigned short len;
+	char name[];
+};
+
+static apk_blob_t cache_item_get_key(apk_hash_item item)
+{
+	struct cache_item *ci = (struct cache_item *) item;
+	return APK_BLOB_PTR_LEN(ci->name, ci->len);
+}
+
+static const struct apk_hash_ops id_hash_ops = {
+	.node_offset = offsetof(struct cache_item, hash_node),
+	.get_key = cache_item_get_key,
+	.hash_key = apk_blob_hash,
+	.compare = apk_blob_compare,
+	.delete_item = (apk_hash_delete_f) free,
+};
+
+static struct cache_item *resolve_cache_item(struct apk_hash *hash, apk_blob_t name)
+{
+	struct cache_item *ci;
+	unsigned long h;
+
+	h = id_hash_ops.hash_key(name);
+	ci = (struct cache_item *) apk_hash_get_hashed(hash, name, h);
+	if (ci != NULL)
+		return ci;
+
+	ci = calloc(1, sizeof(struct cache_item) + name.len);
+	if (ci == NULL)
+		return NULL;
+
+	ci->len = name.len;
+	memcpy(ci->name, name.ptr, name.len);
+	apk_hash_insert_hashed(hash, ci, h);
+
+	return ci;
+}
+
+static unsigned int id_genid = 0;
+static struct apk_hash uid_cache, gid_cache;
+
+void apk_id_cache_init(void)
+{
+	apk_hash_init(&uid_cache, &id_hash_ops, 256);
+	apk_hash_init(&gid_cache, &id_hash_ops, 256);
+	id_genid = 1;
+}
+
+void apk_id_cache_free(void)
+{
+	apk_hash_free(&uid_cache);
+	apk_hash_free(&gid_cache);
+}
+
+void apk_id_cache_reset(void)
+{
+	id_genid++;
+	if (id_genid == 0)
+		id_genid = 1;
+}
+
+uid_t apk_resolve_uid(const char *username, uid_t default_uid)
+{
+	struct cache_item *ci;
+	struct passwd pwent, *pwd;
+	char buf[1024];
+	int r;
+
+	ci = resolve_cache_item(&uid_cache, APK_BLOB_STR(username));
+	if (ci == NULL)
+		return default_uid;
+
+	if (ci->genid != id_genid) {
+		r = getpwnam_r(username, &pwent, buf, sizeof(buf), &pwd);
+		if (pwd != NULL)
+			ci->uid = pwd->pw_uid;
+		else
+			ci->uid = -1;
+		if (r == 0)
+			ci->genid = id_genid;
+	}
+
+	if (ci->uid != -1)
+		return ci->uid;
+
+	return default_uid;
+}
+
+uid_t apk_resolve_gid(const char *groupname, uid_t default_gid)
+{
+	struct cache_item *ci;
+	struct group grent, *grp;
+	char buf[1024];
+	int r;
+
+	ci = resolve_cache_item(&gid_cache, APK_BLOB_STR(groupname));
+	if (ci == NULL)
+		return default_gid;
+
+	if (ci->genid != id_genid) {
+		r = getgrnam_r(groupname, &grent, buf, sizeof(buf), &grp);
+		if (grp != NULL)
+			ci->gid = grp->gr_gid;
+		else
+			ci->gid = -1;
+		if (r == 0)
+			ci->genid = id_genid;
+	}
+
+	if (ci->gid != -1)
+		return ci->gid;
+
+	return default_gid;
+}

src/package.c

@@ -910,6 +910,8 @@ int apk_ipkg_run_script(struct apk_installed_package *ipkg, int root_fd,
 	}
 	waitpid(pid, &status, 0);
 	unlinkat(root_fd, fn, 0);
+	apk_id_cache_reset();
+
 	if (WIFEXITED(status))
 		return WEXITSTATUS(status);
 	return -1;