/* * $Id: dbd_lookup.c,v 1.18 2010-01-19 14:57:11 franklahm Exp $ * * Copyright (C) Joerg Lenneis 2003 * Copyright (C) Frank Lahm 2009 * All Rights Reserved. See COPYING. */ /* CNID salvation spec: general rule: better safe then sorry, so we always delete CNIDs and assign new ones in case of a lookup mismatch. afpd also sends us the CNID found in the adouble file (for AFPVOL_CACHE volumes). In certain cases we can use this hint to determince the right CNID. The lines... Id Did T Dev Inode Name ============================ a b c d e name1 --> f g h i h name2 ...are the expected results of certain operations. (f) is the speced CNID, in some cases it's only intermediate as described in the text and is overridden by another spec. 1) UNIX rename (via mv) or inode reusage(!) ------------------------------------------- Name is possibly changed (rename case) but inode is the same. We should try to keep the CNID, but we cant, because inode reusage is probably much to frequent. rename: 15 2 f 1 1 file --> 15 x f 1 1 renamedfile inode reusage: 15 2 f 1 1 file --> 16 y f 1 1 inodereusagefile Result in dbd_lookup (-: not found, +: found): + devino - didname Possible solution: None. Delete old data, file gets new CNID in both cases (rename and inode). If we got a hint and hint matches the CNID from devino we keep it and update the record. 2) UNIX mv from one folder to another ---------------------------------------- Name is unchanged and inode stays the same, but DID is different. We should try to keep the CNID. 15 2 f 1 1 file --> 15 x f 1 1 file Result in dbd_lookup: + devino - didname Possible solution: strcmp names, if they match keep CNID. Unfortunately this also can't be distinguished from a new file with a reused inode. So me must assign a new CNID. If we got a hint and hint matches the CNID from devino we keep it and update the record. 3) Restore from backup ie change of inode number -- or emacs ------------------------------------------------------------ 15 2 f 1 1 file --> 15 2 f 1 2 file Result in dbd_lookup: - devino + didname Possible fixup solution: test-suite test235 tests and ensures that the CNID is _changed_. The reason for this is somewhat lost in time, but nevertheless we believe our test suite. Similar things happen with emas: emacs uses a backup file (file~). When saving because of inode reusage of the fs, both files most likely exchange inodes. 15 2 f 1 1 file 16 2 f 1 2 file~ --> this would be nice: 15 2 f 1 2 file 16 2 f 1 1 file~ --> but for the reasons described above we must implement 17 2 f 1 2 file 18 2 f 1 1 file~ Result in dbd_lookup for the emacs case: + devino --> CNID: 16 + didname -> CNID: 15 devino search and didname search result in different CNIDs !! Possible fixup solution: to be safe we must assign new CNIDs to both files. */ #ifdef HAVE_CONFIG_H #include "config.h" #endif /* HAVE_CONFIG_H */ #include #include #include #include #include #include #include #include "pack.h" #include "dbif.h" #include "dbd.h" /* * This returns the CNID corresponding to a particular file. It will also fix * up the database if there's a problem. */ int dbd_lookup(DBD *dbd, struct cnid_dbd_rqst *rqst, struct cnid_dbd_rply *rply, int roflag) { unsigned char *buf; DBT key, devdata, diddata; int devino = 1, didname = 1; int rc; cnid_t id_devino, id_didname; u_int32_t type_devino = (unsigned)-1; u_int32_t type_didname = (unsigned)-1; int update = 0; memset(&key, 0, sizeof(key)); memset(&diddata, 0, sizeof(diddata)); memset(&devdata, 0, sizeof(devdata)); rply->namelen = 0; rply->cnid = 0; LOG(log_maxdebug, logtype_cnid, "dbd_lookup(): START"); buf = pack_cnid_data(rqst); /* Look for a CNID. We have two options: dev/ino or did/name. If we only get a match in one of them, that means a file has moved. */ key.data = buf + CNID_DEVINO_OFS; key.size = CNID_DEVINO_LEN; if ((rc = dbif_get(dbd, DBIF_IDX_DEVINO, &key, &devdata, 0)) < 0) { LOG(log_error, logtype_cnid, "dbd_lookup: Unable to get CNID %u, name %s", ntohl(rqst->did), rqst->name); rply->result = CNID_DBD_RES_ERR_DB; return -1; } if (rc == 0) { devino = 0; } else { memcpy(&id_devino, devdata.data, sizeof(rply->cnid)); memcpy(&type_devino, (char *)devdata.data +CNID_TYPE_OFS, sizeof(type_devino)); type_devino = ntohl(type_devino); } key.data = buf + CNID_DID_OFS; key.size = CNID_DID_LEN + rqst->namelen + 1; if ((rc = dbif_get(dbd, DBIF_IDX_DIDNAME, &key, &diddata, 0)) < 0) { LOG(log_error, logtype_cnid, "dbd_lookup: Unable to get CNID %u, name %s", ntohl(rqst->did), rqst->name); rply->result = CNID_DBD_RES_ERR_DB; return -1; } if (rc == 0) { didname = 0; } else { memcpy(&id_didname, diddata.data, sizeof(rply->cnid)); memcpy(&type_didname, (char *)diddata.data +CNID_TYPE_OFS, sizeof(type_didname)); type_didname = ntohl(type_didname); } LOG(log_maxdebug, logtype_cnid, "dbd_lookup(name:'%s', did:%u, dev/ino:0x%llx/0x%llx) {devino: %u, didname: %u}", rqst->name, ntohl(rqst->did), (unsigned long long)rqst->dev, (unsigned long long)rqst->ino, devino, didname); /* Have we found anything at all ? */ if (!devino && !didname) { /* nothing found */ LOG(log_debug, logtype_cnid, "dbd_lookup: name: '%s', did: %u, dev/ino: 0x%llx/0x%llx is not in the CNID database", rqst->name, ntohl(rqst->did), (unsigned long long)rqst->dev, (unsigned long long)rqst->ino); rply->result = CNID_DBD_RES_NOTFOUND; return 1; } /* Check for type (file/dir) mismatch */ if ((devino && (type_devino != rqst->type)) || (didname && (type_didname != rqst->type))) { if (devino && (type_devino != rqst->type)) { /* one is a dir one is a file, remove from db */ LOG(log_debug, logtype_cnid, "dbd_lookup(name:'%s', did:%u, dev/ino:0x%llx/0x%llx): type mismatch for devino", rqst->name, ntohl(rqst->did), (unsigned long long)rqst->dev, (unsigned long long)rqst->ino); if (! roflag) { rqst->cnid = id_devino; rc = dbd_delete(dbd, rqst, rply, DBIF_CNID); rc += dbd_delete(dbd, rqst, rply, DBIF_IDX_DEVINO); rc += dbd_delete(dbd, rqst, rply, DBIF_IDX_DIDNAME); if (rc < 0) { LOG(log_error, logtype_cnid, "dbd_lookup(name:'%s', did:%u, dev/ino:0x%llx/0x%llx): error deleting type mismatch for devino", rqst->name, ntohl(rqst->did), (unsigned long long)rqst->dev, (unsigned long long)rqst->ino); return -1; } } } if (didname && (type_didname != rqst->type)) { /* same: one is a dir one is a file, remove from db */ LOG(log_debug, logtype_cnid, "dbd_lookup(name:'%s', did:%u, dev/ino:0x%llx/0x%llx): type mismatch for didname", rqst->name, ntohl(rqst->did), (unsigned long long)rqst->dev, (unsigned long long)rqst->ino); if (! roflag) { rqst->cnid = id_didname; rc = dbd_delete(dbd, rqst, rply, DBIF_CNID); rc += dbd_delete(dbd, rqst, rply, DBIF_IDX_DEVINO); rc += dbd_delete(dbd, rqst, rply, DBIF_IDX_DIDNAME); if (rc < 0) { LOG(log_error, logtype_cnid, "dbd_lookup(name:'%s', did:%u, dev/ino:0x%llx/0x%llx): error deleting type mismatch for didname", rqst->name, ntohl(rqst->did), (unsigned long long)rqst->dev, (unsigned long long)rqst->ino); return -1; } } } rply->result = CNID_DBD_RES_NOTFOUND; return 1; } if (devino && didname && id_devino == id_didname) { /* everything is fine */ LOG(log_debug, logtype_cnid, "dbd_lookup(DID:%u/'%s',0x%llx/0x%llx): Got CNID: %u", ntohl(rqst->did), rqst->name, (unsigned long long)rqst->dev, (unsigned long long)rqst->ino, htonl(id_didname)); rply->cnid = id_didname; rply->result = CNID_DBD_RES_OK; return 1; } if (devino && didname && id_devino != id_didname) { /* CNIDs don't match, something of a worst case, or possibly 3) emacs! */ LOG(log_debug, logtype_cnid, "dbd_lookup: CNID mismatch: (DID:%u/'%s') --> %u , (0x%llx/0x%llx) --> %u", ntohl(rqst->did), rqst->name, ntohl(id_didname), (unsigned long long)rqst->dev, (unsigned long long)rqst->ino, ntohl(id_devino)); if (! roflag) { rqst->cnid = id_devino; if (dbd_delete(dbd, rqst, rply, DBIF_CNID) < 0) return -1; rqst->cnid = id_didname; if (dbd_delete(dbd, rqst, rply, DBIF_CNID) < 0) return -1; } rply->result = CNID_DBD_RES_NOTFOUND; return 1; } if ( ! didname) { LOG(log_debug, logtype_cnid, "dbd_lookup(CNID hint: %u, DID:%u, \"%s\", 0x%llx/0x%llx): CNID resolve problem: server side rename oder reused inode", ntohl(rqst->cnid), ntohl(rqst->did), rqst->name, (unsigned long long)rqst->dev, (unsigned long long)rqst->ino); if (rqst->cnid == id_devino) { LOG(log_debug, logtype_cnid, "dbd_lookup: server side mv (with resource fork)"); update = 1; } else { if ( ! roflag) { rqst->cnid = id_devino; if (dbd_delete(dbd, rqst, rply, DBIF_CNID) < 0) return -1; } rply->result = CNID_DBD_RES_NOTFOUND; return 1; } } if ( ! devino) { LOG(log_debug, logtype_cnid, "dbd_lookup(DID:%u/'%s',0x%llx/0x%llx): CNID resolve problem: changed dev/ino", ntohl(rqst->did), rqst->name, (unsigned long long)rqst->dev, (unsigned long long)rqst->ino); if ( ! roflag) { rqst->cnid = id_didname; if (dbd_delete(dbd, rqst, rply, DBIF_CNID) < 0) return -1; } rply->result = CNID_DBD_RES_NOTFOUND; return 1; } /* This is also a catch all if we've forgot to catch some possibility with the preceding ifs*/ if (!update || roflag) { rply->result = CNID_DBD_RES_NOTFOUND; return 1; } /* Fix up the database */ rc = dbd_update(dbd, rqst, rply); if (rc >0) { rply->cnid = rqst->cnid; } LOG(log_debug, logtype_cnid, "dbd_lookup(DID:%u/'%s',0x%llx/0x%llx): Got CNID (needed update): %u", ntohl(rqst->did), rqst->name, (unsigned long long)rqst->dev, (unsigned long long)rqst->ino, ntohl(rply->cnid)); return rc; }