X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/f6c347425ac550dd1b7d1ff739bedd1489099d91..4836c3eece276abc14a4574b350f68d8f1e429c0:/uidlist.c

diff --git a/uidlist.c b/uidlist.c
index b7d84ce9..27e7046e 100644
--- a/uidlist.c
+++ b/uidlist.c
@@ -1,17 +1,17 @@
-/* 
+/*
    Copyright (C) Andrew Tridgell 1996
    Copyright (C) Paul Mackerras 1996
-   
+
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.
-   
+
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
-   
+
    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
@@ -25,9 +25,21 @@
 
 #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;
+extern int am_root;
 
 struct idlist {
 	struct idlist *next;
@@ -40,7 +52,7 @@ 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);
@@ -67,48 +79,86 @@ 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;
 }
 
+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();
+		if ((ngroups = getgroups(0, 0)) < 0)
+			ngroups = 0;
+		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
+}
+
 /* this function is a definate candidate for a faster algorithm */
 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;
 
@@ -119,17 +169,18 @@ static uid_t match_uid(uid_t uid)
 		}
 		list = list->next;
 	}
-	
+
 	last_out = uid;
 	return last_out;
 }
 
 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;
 
@@ -141,7 +192,10 @@ static gid_t match_gid(gid_t gid)
 		list = list->next;
 	}
 	
-	last_out = gid;
+	if (am_root || is_in_group(gid))
+		last_out = gid;
+	else
+		last_out = GID_NONE;
 	return last_out;
 }
 
@@ -223,7 +277,7 @@ 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);
 	}
 
@@ -241,7 +295,7 @@ 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;
@@ -253,12 +307,11 @@ 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 +321,13 @@ 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);
+			}
 		}
 	}
 
@@ -276,12 +335,11 @@ 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 +348,27 @@ 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 (!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);
-		}
+	 * 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 && (!am_root || flist->files[i]->gid != 0))
+			flist->files[i]->gid = match_gid(flist->files[i]->gid);
 	}
 }