/* * Copyright (c) 1995, 1996, 1997 Kungliga Tekniska Högskolan * (Royal Institute of Technology, Stockholm, Sweden). * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the Kungliga Tekniska * Högskolan and its contributors. * * 4. Neither the name of the Institute nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include "kafs_locl.h" RCSID("$Id: afskrb.c,v 1.6 1997/05/26 17:38:24 bg Exp $"); #define AUTH_SUPERUSER "afs" /* * Here only ASCII characters are relevant. */ #define IsAsciiLower(c) ('a' <= (c) && (c) <= 'z') #define ToAsciiUpper(c) ((c) - 'a' + 'A') static void foldup(char *a, const char *b) { for (; *b; a++, b++) if (IsAsciiLower(*b)) *a = ToAsciiUpper(*b); else *a = *b; *a = '\0'; } static int get_cred(const char *princ, const char *inst, const char *krealm, CREDENTIALS *c, KTEXT_ST *tkt) { int k_errno = krb_get_cred((char*)princ, (char*)inst, (char*)krealm, c); if (k_errno != KSUCCESS) { k_errno = krb_mk_req(tkt, (char*)princ, (char*)inst, (char*)krealm, 0); if (k_errno == KSUCCESS) k_errno = krb_get_cred((char*)princ, (char*)inst, (char*)krealm, c); } return k_errno; } /* Convert a string to a 32 bit ip number in network byte order. Return 0 on error */ static u_int32_t ip_aton(char *ip) { u_int32_t addr; unsigned int a, b, c, d; if(sscanf(ip, "%u.%u.%u.%u", &a, &b, &c, &d) != 4) return 0; if((a | b | c | d) > 255) return 0; addr = (a << 24) | (b << 16) | (c << 8) | d; addr = htonl(addr); return addr; } /* Try to get a db-server for an AFS cell from a AFSDB record */ static int dns_find_cell(const char *cell, char *dbserver) { struct dns_reply *r; int ok = -1; r = dns_lookup(cell, "afsdb"); if(r){ struct resource_record *rr = r->head; while(rr){ if(rr->type == T_AFSDB && rr->u.afsdb->preference == 1){ strncpy(dbserver, rr->u.afsdb->domain, MaxHostNameLen); dbserver[MaxHostNameLen - 1] = 0; ok = 0; break; } rr = rr->next; } dns_free_data(r); } return ok; } /* Find the realm associated with cell. Do this by opening /usr/vice/etc/CellServDB and getting the realm-of-host for the first VL-server for the cell. This does not work when the VL-server is living in one cell, but the cell it is serving is living in another cell. */ static char* realm_of_cell(const char *cell) { FILE *F; char buf[1024]; u_int32_t addr; struct hostent *hp; char *realm = NULL; if((F = fopen(_PATH_CELLSERVDB, "r"))){ while(fgets(buf, sizeof(buf), F)){ if(buf[0] != '>') continue; if(strncmp(buf + 1, cell, strlen(cell)) == 0){ if(fgets(buf, sizeof(buf), F) == NULL) break; addr = ip_aton(buf); if(addr == 0) break; hp = gethostbyaddr((char*)&addr, 4, AF_INET); if(hp == NULL) break; strncpy (buf, hp->h_name, sizeof(buf)); buf[sizeof(buf) - 1] = '\0'; realm = krb_realmofhost(buf); break; } } fclose(F); } if(realm == NULL){ if(dns_find_cell(cell, buf) == 0) realm = krb_realmofhost(buf); } return realm; } /* * Get tokens for all cells[] */ static int k_afslog_cells(char *cells[], int max, const char *krealm, uid_t uid) { int err = KSUCCESS; int i; for(i = 0; i < max; i++) err = k_afsklog_uid(cells[i], krealm, uid); return err; } /* * Try to find the cells we should try to klog to in "file". */ static void k_find_cells(char *file, char *cells[], int size, int *index) { FILE *f; char cell[64]; int i; f = fopen(file, "r"); if (f == NULL) return; while (*index < size && fgets(cell, sizeof(cell), f)) { char *nl = strchr(cell, '\n'); if (nl) *nl = 0; for(i = 0; i < *index; i++) if(strcmp(cells[i], cell) == 0) break; if(i == *index) cells[(*index)++] = strdup(cell); } fclose(f); } static int k_afsklog_all_local_cells(const char *krealm, uid_t uid) { int err; char *cells[32]; /* XXX */ int num_cells = sizeof(cells) / sizeof(cells[0]); int index = 0; char *p; if ((p = getenv("HOME"))) { char home[MaxPathLen]; if (k_concat(home, sizeof(home), p, "/.TheseCells", NULL) == 0) k_find_cells(home, cells, num_cells, &index); } k_find_cells(_PATH_THESECELLS, cells, num_cells, &index); k_find_cells(_PATH_THISCELL, cells, num_cells, &index); err = k_afslog_cells(cells, index, krealm, uid); while(index > 0) free(cells[--index]); return err; } int k_afsklog_uid(const char *cell, const char *krealm, uid_t uid) { int k_errno; CREDENTIALS c; KTEXT_ST ticket; char realm[REALM_SZ]; char *vl_realm; /* realm of vl-server */ char *lrealm; /* local realm */ char CELL[64]; if (cell == 0 || cell[0] == 0) return k_afsklog_all_local_cells (krealm, uid); foldup(CELL, cell); k_errno = krb_get_lrealm(realm , 0); if(k_errno == KSUCCESS && (krealm == NULL || strcmp(krealm, realm))) lrealm = realm; else lrealm = NULL; /* We're about to find the the realm that holds the key for afs in * the specified cell. The problem is that null-instance * afs-principals are common and that hitting the wrong realm might * yield the wrong afs key. The following assumptions were made. * * Any realm passed to us is preferred. * * If there is a realm with the same name as the cell, it is most * likely the correct realm to talk to. * * In most (maybe even all) cases the database servers of the cell * will live in the realm we are looking for. * * Try the local realm, but if the previous cases fail, this is * really a long shot. * */ /* comments on the ordering of these tests */ /* If the user passes a realm, she probably knows something we don't * know and we should try afs@krealm (otherwise we're talking with a * blondino and she might as well have it.) */ k_errno = -1; if(krealm){ k_errno = get_cred(AUTH_SUPERUSER, cell, krealm, &c, &ticket); if(k_errno) k_errno = get_cred(AUTH_SUPERUSER, "", krealm, &c, &ticket); } if(k_errno) k_errno = get_cred(AUTH_SUPERUSER, cell, CELL, &c, &ticket); if(k_errno) k_errno = get_cred(AUTH_SUPERUSER, "", CELL, &c, &ticket); /* this might work in some conditions */ if(k_errno && (vl_realm = realm_of_cell(cell))){ k_errno = get_cred(AUTH_SUPERUSER, cell, vl_realm, &c, &ticket); if(k_errno) k_errno = get_cred(AUTH_SUPERUSER, "", vl_realm, &c, &ticket); } if(k_errno && lrealm){ k_errno = get_cred(AUTH_SUPERUSER, cell, lrealm, &c, &ticket); #if 0 /* this is most likely never right anyway, but won't fail */ if(k_errno) k_errno = get_cred(AUTH_SUPERUSER, "", lrealm, &c, &ticket); #endif } if (k_errno == KSUCCESS) { struct ViceIoctl parms; struct ClearToken ct; int32_t sizeof_x; char buf[2048], *t; /* * Build a struct ClearToken */ ct.AuthHandle = c.kvno; memcpy (ct.HandShakeKey, c.session, sizeof(c.session)); ct.ViceId = uid; /* is this always valid? */ ct.BeginTimestamp = 1 + c.issue_date; ct.EndTimestamp = krb_life_to_time(c.issue_date, c.lifetime); #define ODD(x) ((x) & 1) /* If we don't know the numerical ID lifetime should be even? */ if (uid == 0 && ODD(ct.EndTimestamp - ct.BeginTimestamp)) ct.BeginTimestamp--; t = buf; /* * length of secret token followed by secret token */ sizeof_x = c.ticket_st.length; memcpy(t, &sizeof_x, sizeof(sizeof_x)); t += sizeof(sizeof_x); memcpy(t, c.ticket_st.dat, sizeof_x); t += sizeof_x; /* * length of clear token followed by clear token */ sizeof_x = sizeof(ct); memcpy(t, &sizeof_x, sizeof(sizeof_x)); t += sizeof(sizeof_x); memcpy(t, &ct, sizeof_x); t += sizeof_x; /* * do *not* mark as primary cell */ sizeof_x = 0; memcpy(t, &sizeof_x, sizeof(sizeof_x)); t += sizeof(sizeof_x); /* * follow with cell name */ sizeof_x = strlen(cell) + 1; memcpy(t, cell, sizeof_x); t += sizeof_x; /* * Build argument block */ parms.in = buf; parms.in_size = t - buf; parms.out = 0; parms.out_size = 0; k_pioctl(0, VIOCSETTOK, &parms, 0); } return k_errno; } int k_afsklog(const char *cell, const char *krealm) { return k_afsklog_uid (cell, krealm, getuid()); }