X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/f6c347425ac550dd1b7d1ff739bedd1489099d91..65fc84b32e2a558cca3a66587ac4cd06e16f1471:/uidlist.c

diff --git a/uidlist.c b/uidlist.c
index b7d84ce9..38c265b3 100644
--- a/uidlist.c
+++ b/uidlist.c
@@ -25,9 +25,17 @@
 
 #include "rsync.h"
 
+#ifdef GETGROUPS_T
+# ifndef NGROUPS_MAX
+/* It ought to be defined, but just in case. */
+#  define NGROUPS_MAX 32
+# endif
+#endif
+
 extern int preserve_uid;
 extern int preserve_gid;
 extern int numeric_ids;
+extern int am_root;
 
 struct idlist {
 	struct idlist *next;
@@ -40,7 +48,7 @@ static struct idlist *gidlist;
 
 static struct idlist *add_list(int id, char *name)
 {
-	struct idlist *list = (struct idlist *)malloc(sizeof(list[0]));
+	struct idlist *list = new(struct idlist);
 	if (!list) out_of_memory("add_list");
 	list->next = NULL;
 	list->name = strdup(name);
@@ -67,38 +75,19 @@ static char *gid_to_name(gid_t gid)
 	return NULL;
 }
 
-
-/* turn a user name into a uid */
-static uid_t name_to_uid(char *name)
-{
-	struct passwd *pass;
-	if (!name || !*name) return 0;
-	pass = getpwnam(name);
-	if (pass) return(pass->pw_uid);
-	return 0;
-}
-
-/* turn a group name into a gid */
-static gid_t name_to_gid(char *name)
-{
-	struct group *grp;
-	if (!name || !*name) return 0;
-	grp = getgrnam(name);
-	if (grp) return(grp->gr_gid);
-	return 0;
-}
-
 static int map_uid(int id, char *name)
 {
-	uid_t uid = name_to_uid(name);
-	if (uid != 0) return uid;
+	uid_t uid;
+	if (uid != 0 && name_to_uid(name, &uid))
+		return uid;
 	return id;
 }
 
 static int map_gid(int id, char *name)
 {
-	gid_t gid = name_to_gid(name);
-	if (gid != 0) return gid;
+	gid_t gid;
+	if (gid != 0 && name_to_gid(name, &gid))
+		return gid;
 	return id;
 }
 
@@ -124,9 +113,52 @@ static uid_t match_uid(uid_t uid)
 	return last_out;
 }
 
+static int is_in_group(gid_t gid)
+{
+#ifdef GETGROUPS_T
+	static gid_t last_in = (gid_t) -2, last_out;
+	static int ngroups = -2;
+	static GETGROUPS_T *gidset;
+	int n;
+
+	if (gid == last_in)
+		return last_out;
+	if (ngroups < -1) {
+		gid_t mygid = getgid();
+		ngroups = getgroups(0, 0);
+		/* If that didn't work, perhaps 0 isn't treated specially? */
+		if (ngroups < 0)
+			ngroups = NGROUPS_MAX;
+		gidset = new_array(GETGROUPS_T, ngroups+1);
+		if (ngroups > 0)
+			ngroups = getgroups(ngroups, gidset);
+		/* The default gid might not be in the list on some systems. */
+		for (n = 0; n < ngroups; n++) {
+			if (gidset[n] == mygid)
+				break;
+		}
+		if (n == ngroups)
+			gidset[ngroups++] = mygid;
+	}
+
+	last_in = gid;
+	last_out = 0;
+	for (n = 0; n < ngroups; n++) {
+		if (gidset[n] == gid) {
+			last_out = 1;
+			break;
+		}
+	}
+	return last_out;
+
+#else
+	return 0;
+#endif
+}
+
 static gid_t match_gid(gid_t gid)
 {
-	static gid_t last_in, last_out;
+	static gid_t last_in = (gid_t) -2, last_out;
 	struct idlist *list = gidlist;
 
 	if (gid == last_in) return last_out;
@@ -141,7 +173,10 @@ static gid_t match_gid(gid_t gid)
 		list = list->next;
 	}
 	
-	last_out = gid;
+	if (am_root)
+		last_out = gid;
+	else
+		last_out = GID_NONE;
 	return last_out;
 }
 
@@ -253,12 +288,11 @@ void recv_uid_list(int f, struct file_list *flist)
 	if (preserve_uid) {
 		/* read the uid list */
 		list = uidlist;
-		id = read_int(f);
-		while (id != 0) {
+		while ((id = read_int(f)) != 0) {
 			int len = read_byte(f);
-			name = (char *)malloc(len);
+			name = new_array(char, len+1);
 			if (!name) out_of_memory("recv_uid_list");
-			read_buf(f, name, len);
+			read_sbuf(f, name, len);
 			if (!list) {
 				uidlist = add_list(id, name);
 				list = uidlist;
@@ -268,7 +302,6 @@ void recv_uid_list(int f, struct file_list *flist)
 			}
 			list->id2 = map_uid(id, name);
 			free(name);
-			id = read_int(f);
 		}
 	}
 
@@ -276,12 +309,11 @@ void recv_uid_list(int f, struct file_list *flist)
 	if (preserve_gid) {
 		/* and the gid list */
 		list = gidlist;
-		id = read_int(f);
-		while (id != 0) {
+		while ((id = read_int(f)) != 0) {
 			int len = read_byte(f);
-			name = (char *)malloc(len);
+			name = new_array(char, len+1);
 			if (!name) out_of_memory("recv_uid_list");
-			read_buf(f, name, len);
+			read_sbuf(f, name, len);
 			if (!list) {
 				gidlist = add_list(id, name);
 				list = gidlist;
@@ -290,21 +322,20 @@ void recv_uid_list(int f, struct file_list *flist)
 				list = list->next;
 			}
 			list->id2 = map_gid(id, name);
+			if (!am_root && !is_in_group(list->id2))
+				list->id2 = GID_NONE;
 			free(name);
-			id = read_int(f);
 		}
 	}
 
-	if (!uidlist && !gidlist) return;
+	if (!(am_root && preserve_uid) && !preserve_gid) return;
 
 	/* now convert the uid/gid of all files in the list to the mapped
 	   uid/gid */
-	for (i=0;i<flist->count;i++) {
-		if (preserve_uid && flist->files[i].uid != 0) {
-			flist->files[i].uid = match_uid(flist->files[i].uid);
-		}
-		if (preserve_gid && flist->files[i].gid != 0) {
-			flist->files[i].gid = match_gid(flist->files[i].gid);
-		}
+	for (i = 0; i < flist->count; i++) {
+		if (am_root && preserve_uid && flist->files[i]->uid != 0)
+			flist->files[i]->uid = match_uid(flist->files[i]->uid);
+		if (preserve_gid && (!am_root || flist->files[i]->gid != 0))
+			flist->files[i]->gid = match_gid(flist->files[i]->gid);
 	}
 }