Date: Wed, 28 Feb 2001 20:12:34 -0800 From: Dima Dorfman <dima@unixfreak.org> To: audit@freebsd.org Subject: Propagating the nodump flag Message-ID: <20010301041234.9F3D63E09@bazooka.unixfreak.org>
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Some time ago, on -arch, phk proposed that the nodump flag should be propagated if it's set on a directory (see 'inheriting the "nodump" flag ?' around Dec. 2000). This was generally considered a good idea, however, the patch to the kernel he proposed was thought an ugly hack. In addition, jeroen pointed out that NetBSD had implemented this functionality the Right Way(tm), in dump(8). Attached below is a port of NetBSD's patch to FreeBSD's dump(8). The patch is probably more complex than it should have been due to dump's obscure tree-walker. For the technical details of what it does, see: http://lists.openresources.com/NetBSD/tech-kern/msg00453.html (note that the patch there is not identical to the one below, and should not be used; the reference is provided for its excellent technical explanation of the patch). I've been using this on two of my hosts for a while, and it works as expected. Given the additional fact that NetBSD has had this for almost two years, and that the patch below looks very similar to the one they applied, I doubt it significantly breaks anything. Comments? Reviews? Thanks in advance Dima Dorfman dima@unixfreak.org Index: traverse.c =================================================================== RCS file: /st/src/FreeBSD/src/sbin/dump/traverse.c,v retrieving revision 1.11 diff -u -r1.11 traverse.c --- traverse.c 2000/04/14 06:14:59 1.11 +++ traverse.c 2001/02/20 01:39:06 @@ -74,9 +74,11 @@ typedef long fsizeT; #endif -static int dirindir __P((ino_t ino, daddr_t blkno, int level, long *size)); +static int dirindir __P((ino_t ino, daddr_t blkno, int level, long *size, + long *tapesize, int nodump)); static void dmpindir __P((ino_t ino, daddr_t blk, int level, fsizeT *size)); -static int searchdir __P((ino_t ino, daddr_t blkno, long size, long filesize)); +static int searchdir __P((ino_t ino, daddr_t blkno, long size, long filesize, + long *tapesize, int nodump)); /* * This is an estimation of the number of TP_BSIZE blocks in the file. @@ -152,10 +154,14 @@ dp = getino(ino); if ((mode = (dp->di_mode & IFMT)) == 0) continue; - SETINO(ino, usedinomap); + /* + * All dirs go in dumpdirmap; only inodes that are to + * be dumped go in usedinomap and dumpinomap, however. + */ if (mode == IFDIR) SETINO(ino, dumpdirmap); if (WANTTODUMP(dp)) { + SETINO(ino, usedinomap); SETINO(ino, dumpinomap); if (mode != IFREG && mode != IFDIR && mode != IFLNK) *tapesize += 1; @@ -192,9 +198,10 @@ long *tapesize; { register struct dinode *dp; - register int i, isdir; + register int i, isdir, nodump; register char *map; register ino_t ino; + struct dinode di; long filesize; int ret, change = 0; @@ -204,24 +211,34 @@ isdir = *map++; else isdir >>= 1; - if ((isdir & 1) == 0 || TSTINO(ino, dumpinomap)) + /* + * If a directory has been removed from usedinomap, it + * either has the nodump flag set, or has inherited + * it. Although a directory can't be in dumpinomap if + * it isn't in usedinomap, we have to go through it to + * propagate the nodump flag. + */ + nodump = (TSTINO(ino, usedinomap) == 0); + if ((isdir & 1) == 0 || (TSTINO(ino, dumpinomap) && !nodump)) continue; dp = getino(ino); - filesize = dp->di_size; + di = *dp; /* inode buf may change in searchdir(). */ + filesize = di.di_size; for (ret = 0, i = 0; filesize > 0 && i < NDADDR; i++) { - if (dp->di_db[i] != 0) - ret |= searchdir(ino, dp->di_db[i], + if (di.di_db[i] != 0) + ret |= searchdir(ino, di.di_db[i], (long)dblksize(sblock, dp, i), - filesize); + filesize, tapesize, nodump); if (ret & HASDUMPEDFILE) filesize = 0; else filesize -= sblock->fs_bsize; } for (i = 0; filesize > 0 && i < NIADDR; i++) { - if (dp->di_ib[i] == 0) + if (di.di_ib[i] == 0) continue; - ret |= dirindir(ino, dp->di_ib[i], i, &filesize); + ret |= dirindir(ino, di.di_ib[i], i, &filesize, + tapesize, nodump); } if (ret & HASDUMPEDFILE) { SETINO(ino, dumpinomap); @@ -229,12 +246,15 @@ change = 1; continue; } - if ((ret & HASSUBDIRS) == 0) { + if (nodump) { + if (ret & HASSUBDIRS) + change = 1; /* subdirs inherit nodump */ + CLRINO(ino, dumpdirmap); + } else if ((ret & HASSUBDIRS) == 0) if (!TSTINO(ino, dumpinomap)) { CLRINO(ino, dumpdirmap); change = 1; } - } } return (change); } @@ -245,11 +265,13 @@ * require the directory to be dumped. */ static int -dirindir(ino, blkno, ind_level, filesize) +dirindir(ino, blkno, ind_level, filesize, tapesize, nodump) ino_t ino; daddr_t blkno; int ind_level; long *filesize; + long *tapesize; + int nodump; { int ret = 0; register int i; @@ -261,7 +283,7 @@ blkno = idblk[i]; if (blkno != 0) ret |= searchdir(ino, blkno, sblock->fs_bsize, - *filesize); + *filesize, tapesize, nodump); if (ret & HASDUMPEDFILE) *filesize = 0; else @@ -273,7 +295,8 @@ for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) { blkno = idblk[i]; if (blkno != 0) - ret |= dirindir(ino, blkno, ind_level, filesize); + ret |= dirindir(ino, blkno, ind_level, filesize, + tapesize, nodump); } return (ret); } @@ -284,13 +307,16 @@ * contains any subdirectories. */ static int -searchdir(ino, blkno, size, filesize) +searchdir(ino, blkno, size, filesize, tapesize, nodump) ino_t ino; daddr_t blkno; register long size; long filesize; + long *tapesize; + int nodump; { register struct direct *dp; + register struct dinode *ip; register long loc, ret = 0; char dblk[MAXBSIZE]; @@ -311,16 +337,30 @@ continue; if (dp->d_name[1] == '.' && dp->d_name[2] == '\0') continue; - } - if (TSTINO(dp->d_ino, dumpinomap)) { - ret |= HASDUMPEDFILE; - if (ret & HASSUBDIRS) - break; } - if (TSTINO(dp->d_ino, dumpdirmap)) { - ret |= HASSUBDIRS; - if (ret & HASDUMPEDFILE) - break; + if (nodump) { + ip = getino(dp->d_ino); + if (TSTINO(dp->d_ino, dumpinomap)) { + CLRINO(dp->d_ino, dumpinomap); + CLRINO(dp->d_ino, usedinomap); + *tapesize -= blockest(ip); + } + /* Add back to dumpdirmap to propagate nodump. */ + if ((ip->di_mode & IFMT) == IFDIR) { + SETINO(dp->d_ino, dumpdirmap); + ret |= HASSUBDIRS; + } + } else { + if (TSTINO(dp->d_ino, dumpinomap)) { + ret |= HASDUMPEDFILE; + if (ret & HASSUBDIRS) + break; + } + if (TSTINO(dp->d_ino, dumpdirmap)) { + ret |= HASSUBDIRS; + if (ret & HASDUMPEDFILE) + break; + } } } return (ret); To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-audit" in the body of the message
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