X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/58cadc8608fbb2cbc7b74578cd92de4337a4b887..05118158f4f59a5f512e5bab640f253332a6e181:/uidlist.c

diff --git a/uidlist.c b/uidlist.c
index d8a7af11..0319d606 100644
--- a/uidlist.c
+++ b/uidlist.c
@@ -25,6 +25,17 @@
 
 #include "rsync.h"
 
+#ifdef HAVE_GETGROUPS
+# if !defined(GETGROUPS_T)
+#  define GETGROUPS_T gid_t
+# endif
+# ifndef NGROUPS_MAX
+/* It ought to be defined, but just in case. */
+#  define NGROUPS_MAX 32
+# endif
+#endif
+
+extern int verbose;
 extern int preserve_uid;
 extern int preserve_gid;
 extern int numeric_ids;
@@ -71,7 +82,7 @@ static char *gid_to_name(gid_t gid)
 static int map_uid(int id, char *name)
 {
 	uid_t uid;
-	if (name_to_uid(name, &uid) && uid != 0)
+	if (uid != 0 && name_to_uid(name, &uid))
 		return uid;
 	return id;
 }
@@ -79,7 +90,7 @@ static int map_uid(int id, char *name)
 static int map_gid(int id, char *name)
 {
 	gid_t gid;
-	if (name_to_gid(name, &gid) && gid != 0)
+	if (gid != 0 && name_to_gid(name, &gid))
 		return gid;
 	return id;
 }
@@ -90,7 +101,8 @@ static uid_t match_uid(uid_t uid)
 	static uid_t last_in, last_out;
 	struct idlist *list = uidlist;
 
-	if (uid == last_in) return last_out;
+	if (uid == last_in)
+		return last_out;
 
 	last_in = uid;
 
@@ -106,12 +118,71 @@ static uid_t match_uid(uid_t uid)
 	return last_out;
 }
 
+static int is_in_group(gid_t gid)
+{
+#ifdef HAVE_GETGROUPS
+	static gid_t last_in = GID_NONE, 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 = MY_GID();
+		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;
+		if (verbose > 3) {
+			char gidbuf[NGROUPS_MAX*16+32];
+			int pos;
+			sprintf(gidbuf, "process has %d gid%s: ",
+			    ngroups, ngroups == 1? "" : "s");
+			pos = strlen(gidbuf);
+			for (n = 0; n < ngroups; n++) {
+				sprintf(gidbuf+pos, " %ld", (long)gidset[n]);
+				pos += strlen(gidbuf+pos);
+			}
+			rprintf(FINFO, "%s\n", gidbuf);
+		}
+	}
+
+	last_in = gid;
+	for (n = 0; n < ngroups; n++) {
+		if (gidset[n] == gid)
+			return last_out = 1;
+	}
+	return last_out = 0;
+
+#else
+	static gid_t mygid = GID_NONE;
+	if (mygid == GID_NONE) {
+		mygid = MY_GID();
+		if (verbose > 3)
+			rprintf(FINFO, "process has gid %ld\n", (long)mygid);
+	}
+	return gid == mygid;
+#endif
+}
+
 static gid_t match_gid(gid_t gid)
 {
-	static gid_t last_in, last_out;
+	static gid_t last_in = GID_NONE, last_out = GID_NONE;
 	struct idlist *list = gidlist;
 
-	if (gid == last_in) return last_out;
+	if (gid == last_in)
+		return last_out;
 
 	last_in = gid;
 
@@ -126,7 +197,7 @@ static gid_t match_gid(gid_t gid)
 	if (am_root)
 		last_out = gid;
 	else
-		last_out = (gid_t) -1;
+		last_out = GID_NONE;
 	return last_out;
 }
 
@@ -208,7 +279,7 @@ void send_uid_list(int f)
 		}
 
 		/* terminate the uid list with a 0 uid. We explicitly exclude
-		   0 from the list */
+		 * 0 from the list */
 		write_int(f, 0);
 	}
 
@@ -226,7 +297,7 @@ void send_uid_list(int f)
 }
 
 /* recv a complete uid/gid mapping from the peer and map the uid/gid
-   in the file list to local names */
+ * in the file list to local names */
 void recv_uid_list(int f, struct file_list *flist)
 {
 	int id, i;
@@ -238,8 +309,7 @@ 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 = new_array(char, len+1);
 			if (!name) out_of_memory("recv_uid_list");
@@ -253,7 +323,13 @@ void recv_uid_list(int f, struct file_list *flist)
 			}
 			list->id2 = map_uid(id, name);
 			free(name);
-			id = read_int(f);
+		}
+		if (verbose > 3) {
+			for (list = uidlist; list; list = list->next) {
+				rprintf(FINFO, "uid %ld (%s) maps to %ld\n",
+				    (long)list->id, list->name,
+				    (long)list->id2);
+			}
 		}
 	}
 
@@ -261,8 +337,7 @@ 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 = new_array(char, len+1);
 			if (!name) out_of_memory("recv_uid_list");
@@ -275,21 +350,27 @@ 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 (verbose > 3) {
+			for (list = gidlist; list; list = list->next) {
+				rprintf(FINFO, "gid %ld (%s) maps to %ld\n",
+				    (long)list->id, list->name,
+				    (long)list->id2);
+			}
 		}
 	}
 
 	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 (am_root && preserve_uid && flist->files[i]->uid != 0) {
+	 * uid/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 && flist->files[i]->gid != 0) {
+		if (preserve_gid && (!am_root || flist->files[i]->gid != 0))
 			flist->files[i]->gid = match_gid(flist->files[i]->gid);
-		}
 	}
 }