/* acl.c - routines to parse and check acl's */ /* $OpenLDAP$ */ /* * Copyright 1998-1999 The OpenLDAP Foundation, All Rights Reserved. * COPYING RESTRICTIONS APPLY, see COPYRIGHT file */ #include "portable.h" #include #include #include #include #include "slap.h" #ifdef SLAPD_ACI_ENABLED int aci_access_allowed (struct berval *aci, char *attr, Backend *be, Entry *e, Operation *op, int access, char *edn, regmatch_t *matches); #endif static int regex_matches(char *pat, char *str, char *buf, regmatch_t *matches); static void string_expand(char *newbuf, int bufsiz, char *pattern, char *match, regmatch_t *matches); /* * access_allowed - check whether op->o_ndn is allowed the requested access * to entry e, attribute attr, value val. if val is null, access to * the whole attribute is assumed (all values). this routine finds * the applicable acl and calls acl_access_allowed() to make the * decision. * * returns 0 access NOT allowed * 1 access allowed */ int access_allowed( Backend *be, Connection *conn, Operation *op, Entry *e, char *attr, struct berval *val, int access ) { int rc; AccessControl *a; char *edn; regmatch_t matches[MAXREMATCHES]; int i; int n; if ( be == NULL ) { return( 0 ); } edn = e->e_ndn; Debug( LDAP_DEBUG_ACL, "\n=> access_allowed: entry (%s) attr (%s)\n", e->e_dn, attr, 0 ); /* the lastmod attributes are ignored by ACL checking */ if ( oc_check_no_usermod_attr( attr ) ) { Debug( LDAP_DEBUG_ACL, "Operational attribute: %s access allowed\n", attr, 0, 0 ); return(1); } memset(matches, 0, sizeof(matches)); a = acl_get_applicable( be, op, e, attr, MAXREMATCHES, matches ); if (a) { for (i = 0; i < MAXREMATCHES && matches[i].rm_so > 0; i++) { Debug( LDAP_DEBUG_ARGS, "=> match[%d]: %d %d ", i, (int)matches[i].rm_so, (int)matches[i].rm_eo ); if( matches[i].rm_so <= matches[0].rm_eo ) { for ( n = matches[i].rm_so; n < matches[i].rm_eo; n++) { Debug( LDAP_DEBUG_ARGS, "%c", edn[n], 0, 0 ); } } Debug( LDAP_DEBUG_ARGS, "\n", 0, 0, 0 ); } } rc = acl_access_allowed( a, attr, be, conn, e, val, op, access, edn, matches ); Debug( LDAP_DEBUG_ACL, "\n=> access_allowed: exit (%s) attr (%s)\n", e->e_dn, attr, 0); return( rc ); } /* * acl_get_applicable - return the acl applicable to entry e, attribute * attr. the acl returned is suitable for use in subsequent calls to * acl_access_allowed(). */ AccessControl * acl_get_applicable( Backend *be, Operation *op, Entry *e, char *attr, int nmatch, regmatch_t *matches ) { int i; AccessControl *a; char *edn; Debug( LDAP_DEBUG_ACL, "\n=> acl_get: entry (%s) attr (%s)\n", e->e_dn, attr, 0 ); if ( be_isroot( be, op->o_ndn ) ) { Debug( LDAP_DEBUG_ACL, "<= acl_get: no acl applicable to database root\n", 0, 0, 0 ); return( NULL ); } edn = e->e_ndn; Debug( LDAP_DEBUG_ARGS, "=> acl_get: edn %s\n", edn, 0, 0 ); /* check for a backend-specific acl that matches the entry */ for ( i = 1, a = be->be_acl; a != NULL; a = a->acl_next, i++ ) { if (a->acl_dn_pat != NULL) { Debug( LDAP_DEBUG_TRACE, "=> dnpat: [%d] %s nsub: %d\n", i, a->acl_dn_pat, (int) a->acl_dn_re.re_nsub); if (regexec(&a->acl_dn_re, edn, nmatch, matches, 0)) { continue; } else { Debug( LDAP_DEBUG_TRACE, "=> acl_get:[%d] backend ACL match\n", i, 0, 0); } } if ( a->acl_filter != NULL ) { if ( test_filter( NULL, NULL, NULL, e, a->acl_filter ) != 0 ) { continue; } } Debug( LDAP_DEBUG_ARGS, "=> acl_get: [%d] check attr %s\n", i, attr, 0); if ( attr == NULL || a->acl_attrs == NULL || charray_inlist( a->acl_attrs, attr ) ) { Debug( LDAP_DEBUG_ACL, "<= acl_get: [%d] backend acl %s attr: %s\n", i, e->e_dn, attr ); return( a ); } matches[0].rm_so = matches[0].rm_eo = -1; } /* check for a global acl that matches the entry */ for ( i = 1, a = global_acl; a != NULL; a = a->acl_next, i++ ) { if (a->acl_dn_pat != NULL) { Debug( LDAP_DEBUG_TRACE, "=> dn pat: [%d] %s nsub: %d\n", i, a->acl_dn_pat, (int) a->acl_dn_re.re_nsub); if (regexec(&a->acl_dn_re, edn, nmatch, matches, 0)) { continue; } else { Debug( LDAP_DEBUG_TRACE, "=> acl_get: [%d] global ACL match\n", i, 0, 0); } } if ( a->acl_filter != NULL ) { if ( test_filter( NULL, NULL, NULL, e, a->acl_filter ) != 0 ) { continue; } } Debug( LDAP_DEBUG_ARGS, "=> acl_get: [%d] check attr\n", i, 0, 0); if ( attr == NULL || a->acl_attrs == NULL || charray_inlist( a->acl_attrs, attr ) ) { Debug( LDAP_DEBUG_ACL, "<= acl_get: [%d] global acl %s attr: %s\n", i, e->e_dn, attr ); return( a ); } matches[0].rm_so = matches[0].rm_eo = -1; } Debug( LDAP_DEBUG_ACL, "<= acl_get: no match\n", 0, 0, 0 ); return( NULL ); } /* * acl_access_allowed - check whether the given acl allows dn the * requested access to entry e, attribute attr, value val. if val * is null, access to the whole attribute is assumed (all values). * * returns 0 access NOT allowed * 1 access allowed */ int acl_access_allowed( AccessControl *a, char *attr, Backend *be, Connection *conn, Entry *e, struct berval *val, Operation *op, int access, char *edn, regmatch_t *matches ) { int i; Access *b; int default_access; Debug( LDAP_DEBUG_ACL, "\n=> acl_access_allowed: %s access to entry \"%s\"\n", access2str( access ), e->e_dn, 0 ); Debug( LDAP_DEBUG_ACL, "\n=> acl_access_allowed: %s access to value \"%s\" by \"%s\"\n", access2str( access ), val ? val->bv_val : "any", op->o_ndn ? op->o_ndn : "" ); if ( be_isroot( be, op->o_ndn ) ) { Debug( LDAP_DEBUG_ACL, "<= acl_access_allowed: granted to database root\n", 0, 0, 0 ); return( 1 ); } default_access = be->be_dfltaccess ? be->be_dfltaccess : global_default_access; if ( a == NULL ) { Debug( LDAP_DEBUG_ACL, "<= acl_access_allowed: %s by default (no matching to)\n", default_access >= access ? "granted" : "denied", 0, 0 ); return( default_access >= access ); } for ( i = 1, b = a->acl_access; b != NULL; b = b->a_next, i++ ) { /* AND clauses */ if ( b->a_dn_pat != NULL ) { Debug( LDAP_DEBUG_TRACE, "<= check a_dn_pat: %s\n", b->a_dn_pat, 0, 0); /* * if access applies to the entry itself, and the * user is bound as somebody in the same namespace as * the entry, OR the given dn matches the dn pattern */ if ( strcasecmp( b->a_dn_pat, "anonymous" ) == 0 ) { if (op->o_ndn != NULL && op->o_ndn[0] != '\0' ) { continue; } } else if ( strcasecmp( b->a_dn_pat, "self" ) == 0 ) { if( op->o_ndn == NULL || op->o_ndn[0] == '\0' ) { continue; } if ( e->e_dn == NULL || strcmp( edn, op->o_ndn ) != 0 ) { continue; } } else if ( strcmp( b->a_dn_pat, ".*" ) != 0 && !regex_matches( b->a_dn_pat, op->o_ndn, edn, matches ) ) { continue; } } if ( b->a_sockurl_pat != NULL ) { Debug( LDAP_DEBUG_ARGS, "<= check a_sockurl_pat: %s\n", b->a_sockurl_pat, 0, 0 ); if ( strcmp( b->a_sockurl_pat, ".*" ) != 0 && !regex_matches( b->a_sockurl_pat, conn->c_listener_url, edn, matches ) ) { continue; } } if ( b->a_domain_pat != NULL ) { Debug( LDAP_DEBUG_ARGS, "<= check a_domain_pat: %s\n", b->a_domain_pat, 0, 0 ); if ( strcmp( b->a_domain_pat, ".*" ) != 0 && !regex_matches( b->a_domain_pat, conn->c_peer_domain, edn, matches ) ) { continue; } } if ( b->a_peername_pat != NULL ) { Debug( LDAP_DEBUG_ARGS, "<= check a_peername_path: %s\n", b->a_peername_pat, 0, 0 ); if ( strcmp( b->a_peername_pat, ".*" ) != 0 && !regex_matches( b->a_peername_pat, conn->c_peer_name, edn, matches ) ) { continue; } } if ( b->a_sockname_pat != NULL ) { Debug( LDAP_DEBUG_ARGS, "<= check a_sockname_path: %s\n", b->a_sockname_pat, 0, 0 ); if ( strcmp( b->a_sockname_pat, ".*" ) != 0 && !regex_matches( b->a_sockname_pat, conn->c_sock_name, edn, matches ) ) { continue; } } if ( b->a_dn_at != NULL && op->o_ndn != NULL ) { Attribute *at; struct berval bv; Debug( LDAP_DEBUG_ARGS, "<= check a_dn_at: %s\n", b->a_dn_at, 0, 0); bv.bv_val = op->o_ndn; bv.bv_len = strlen( bv.bv_val ); /* see if asker is listed in dnattr */ if ( (at = attr_find( e->e_attrs, b->a_dn_at )) != NULL && value_find( at->a_vals, &bv, at->a_syntax, 3 ) == 0 ) { if ( ACL_IS_SELF(b->a_access) && (val == NULL || value_cmp( &bv, val, at->a_syntax, 2 )) ) { continue; } /* asker not listed in dnattr - check for self access */ } else if ( ! ACL_IS_SELF(b->a_access) || val == NULL || value_cmp( &bv, val, at->a_syntax, 2 ) != 0 ) { continue; } } if ( b->a_group_pat != NULL && op->o_ndn != NULL ) { char buf[1024]; /* b->a_group is an unexpanded entry name, expanded it should be an * entry with objectclass group* and we test to see if odn is one of * the values in the attribute group */ /* see if asker is listed in dnattr */ string_expand(buf, sizeof(buf), b->a_group_pat, edn, matches); if ( dn_normalize(buf) == NULL ) { /* did not expand to a valid dn */ continue; } if (backend_group(be, e, buf, op->o_ndn, b->a_group_oc, b->a_group_at) != 0) { continue; } } #ifdef SLAPD_ACI_ENABLED if ( b->a_aci_at != NULL ) { Attribute *at; /* this case works different from the others above. * since aci's themselves give permissions, we need * to first check b->a_access, the ACL's access level. */ if( op->o_ndn == NULL || op->o_ndn[0] == '\0' ) { continue; } if ( e->e_dn == NULL ) { continue; } /* first check if the right being requested is * higher than allowed by the ACL clause. */ if ( ! ACL_GRANT( b->a_access, access ) ) { continue; } /* get the aci attribute */ at = attr_find( e->e_attrs, b->a_aci_at ); if ( at == NULL ) { continue; } /* the aci is an multi-valued attribute. The * rights are determined by OR'ing the individual * rights given by the acis. */ for ( i = 0; at->a_vals[i] != NULL; i++ ) { if ( aci_access_allowed( at->a_vals[i], attr, be, e, op, access, edn, matches ) ) { Debug( LDAP_DEBUG_ACL, "<= acl_access_allowed: matched by clause #%d access granted\n", i, 0, 0 ); return(1); } } continue; } #endif Debug( LDAP_DEBUG_ACL, "<= acl_access_allowed: matched by clause #%d access %s\n", i, ACL_GRANT(b->a_access, access) ? "granted" : "denied", 0 ); return ACL_GRANT(b->a_access, access ); } Debug( LDAP_DEBUG_ACL, "<= acl_access_allowed: %s by default (no matching by)\n", default_access >= access ? "granted" : "denied", 0, 0 ); return( default_access >= access ); } /* * acl_check_modlist - check access control on the given entry to see if * it allows the given modifications by the user associated with op. * returns LDAP_SUCCESS mods allowed ok * anything else mods not allowed - return is an error * code indicating the problem */ int acl_check_modlist( Backend *be, Connection *conn, Operation *op, Entry *e, LDAPModList *mlist ) { int i; AccessControl *a; char *edn = e->e_ndn; for ( ; mlist != NULL; mlist = mlist->ml_next ) { regmatch_t matches[MAXREMATCHES]; /* the lastmod attributes are ignored by ACL checking */ if ( oc_check_no_usermod_attr( mlist->ml_type ) ) { Debug( LDAP_DEBUG_ACL, "Operational attribute: %s access allowed\n", mlist->ml_type, 0, 0 ); continue; } a = acl_get_applicable( be, op, e, mlist->ml_type, MAXREMATCHES, matches ); switch ( mlist->ml_op & ~LDAP_MOD_BVALUES ) { case LDAP_MOD_REPLACE: case LDAP_MOD_ADD: if ( mlist->ml_bvalues == NULL ) { break; } for ( i = 0; mlist->ml_bvalues[i] != NULL; i++ ) { if ( ! acl_access_allowed( a, mlist->ml_type, be, conn, e, mlist->ml_bvalues[i], op, ACL_WRITE, edn, matches) ) { return( LDAP_INSUFFICIENT_ACCESS ); } } break; case LDAP_MOD_DELETE: if ( mlist->ml_bvalues == NULL ) { if ( ! acl_access_allowed( a, mlist->ml_type, be, conn, e, NULL, op, ACL_WRITE, edn, matches) ) { return( LDAP_INSUFFICIENT_ACCESS ); } break; } for ( i = 0; mlist->ml_bvalues[i] != NULL; i++ ) { if ( ! acl_access_allowed( a, mlist->ml_type, be, conn, e, mlist->ml_bvalues[i], op, ACL_WRITE, edn, matches) ) { return( LDAP_INSUFFICIENT_ACCESS ); } } break; } } return( LDAP_SUCCESS ); } #ifdef SLAPD_ACI_ENABLED static char * aci_bvstrdup (struct berval *bv) { char *s; s = (char *)ch_malloc(bv->bv_len + 1); if (s != NULL) { memcpy(s, bv->bv_val, bv->bv_len); s[bv->bv_len] = 0; } return(s); } static int aci_strbvcmp (char *s, struct berval *bv) { int res, len; res = strncasecmp( s, bv->bv_val, bv->bv_len ); if (res) return(res); len = strlen(s); if (len > bv->bv_len) return(1); if (len < bv->bv_len) return(-1); return(0); } static int aci_get_part (struct berval *list, int ix, char sep, struct berval *bv) { int len; char *p; if (bv) { bv->bv_len = 0; bv->bv_val = NULL; } len = list->bv_len; p = list->bv_val; while (len >= 0 && --ix >= 0) { while (--len >= 0 && *p++ != sep) ; } while (len >= 0 && *p == ' ') { len--; p++; } if (len < 0) return(-1); if (!bv) return(0); bv->bv_val = p; while (--len >= 0 && *p != sep) { bv->bv_len++; p++; } while (bv->bv_len > 0 && *--p == ' ') bv->bv_len--; return(bv->bv_len); } static int aci_list_has_right (struct berval *list, int access, int action) { struct berval bv; int i, right; for (i = 0; aci_get_part(list, i, ',', &bv) >= 0; i++) { if (bv.bv_len <= 0) continue; switch (*bv.bv_val) { case 'c': right = ACL_COMPARE; break; case 's': /* **** NOTE: draft-ietf-ldapext-aci-model-0.3.txt defines * the right 's' to mean "set", but in the examples states * that the right 's' means "search". The latter definition * is used here. */ right = ACL_SEARCH; break; case 'r': right = ACL_READ; break; case 'w': right = ACL_WRITE; break; case 'x': /* **** NOTE: draft-ietf-ldapext-aci-model-0.3.txt does not * define any equivalent to the AUTH right, so I've just used * 'x' for now. */ right = ACL_AUTH; break; default: right = 0; break; } #ifdef SLAPD_ACI_DISCRETE_RIGHTS if (right & access) { return(action); } #else if (action != 0) { /* check granted */ if (ACL_GRANT(right, access)) return(1); } else { /* check denied */ if (right <= access) return(1); } #endif } #ifdef SLAPD_ACI_DISCRETE_RIGHTS return(!action); #else return(0); #endif } static int aci_list_has_attr (struct berval *list, char *attr) { struct berval bv; int i; for (i = 0; aci_get_part(list, i, ',', &bv) >= 0; i++) { if (aci_strbvcmp(attr, &bv) == 0) { return(1); } } return(0); } static int aci_list_has_attr_right (struct berval *list, char *attr, int access, int action) { struct berval bv; int i, found; /* loop through each rights/attr pair, skip first part (action) */ found = -1; for (i = 1; aci_get_part(list, i + 1, ';', &bv) >= 0; i += 2) { if (aci_list_has_attr(&bv, attr) == 0) continue; found = 0; if (aci_get_part(list, i, ';', &bv) < 0) continue; if (aci_list_has_right(&bv, access, action) != 0) return(1); } return(found); } static int aci_list_has_permission (struct berval *list, char *attr, int access) { struct berval perm, actn; int i, action, specific, general; if (attr == NULL || *attr == 0 || strcasecmp(attr, "entry") == 0) { attr = "[entry]"; } /* loop through each permissions clause */ for (i = 0; aci_get_part(list, i, '$', &perm) >= 0; i++) { if (aci_get_part(&perm, 0, ';', &actn) < 0) continue; if (aci_strbvcmp( "grant", &actn ) == 0) { action = 1; } else if (aci_strbvcmp( "deny", &actn ) == 0) { action = 0; } else { continue; } specific = aci_list_has_attr_right(&perm, attr, access, action); if (specific >= 0) return(specific); general = aci_list_has_attr_right(&perm, "[all]", access, action); if (general >= 0) return(general); } return(0); } static int aci_group_member ( struct berval *subj, char *grpoc, char *grpat, Backend *be, Entry *e, Operation *op, char *edn, regmatch_t *matches ) { struct berval bv; char *subjdn, *grpdn; int rc = 0; /* format of string is "group/objectClassValue/groupAttrName" */ if (aci_get_part(subj, 0, '/', &bv) < 0) return(0); subjdn = aci_bvstrdup(&bv); if (subjdn == NULL) return(0); if (aci_get_part(subj, 1, '/', &bv) < 0) grpoc = ch_strdup(grpoc); else grpoc = aci_bvstrdup(&bv); if (aci_get_part(subj, 2, '/', &bv) < 0) grpat = ch_strdup(grpat); else grpat = aci_bvstrdup(&bv); grpdn = (char *)ch_malloc(1024); if (grpoc != NULL && grpat != NULL && grpdn != NULL) { string_expand(grpdn, 1024, subjdn, edn, matches); if ( dn_normalize(grpdn) != NULL ) { rc = (backend_group(be, e, grpdn, op->o_ndn, grpoc, grpat) == 0); } ch_free(grpdn); } if (grpat != NULL) ch_free(grpat); if (grpoc != NULL) ch_free(grpoc); ch_free(subjdn); return(rc); } int aci_access_allowed ( struct berval *aci, char *attr, Backend *be, Entry *e, Operation *op, int access, char *edn, regmatch_t *matches ) { struct berval bv, perms, sdn; char *subjdn; int rc; Debug( LDAP_DEBUG_ACL, "\n=> aci_access_allowed: %s access to entry \"%s\"\n", access2str( access ), e->e_dn, 0 ); Debug( LDAP_DEBUG_ACL, "\n=> aci_access_allowed: %s access to attribute \"%s\" by \"%s\"\n", access2str( access ), attr, op->o_ndn ? op->o_ndn : "" ); /* parse an aci of the form: oid#scope#action;rights;attr;rights;attr$action;rights;attr;rights;attr#dnType#subjectDN See draft-ietf-ldapext-aci-model-0.3.txt section 9.1 for a full description of the format for this attribute. For now, this routine only supports scope=entry. */ /* check that the aci has all 5 components */ if (aci_get_part(aci, 4, '#', NULL) < 0) return(0); /* check that the scope is "entry" */ if (aci_get_part(aci, 1, '#', &bv) < 0 || aci_strbvcmp( "entry", &bv ) != 0) { return(0); } /* get the list of permissions clauses, bail if empty */ if (aci_get_part(aci, 2, '#', &perms) <= 0) return(0); /* check if any permissions allow desired access */ if (aci_list_has_permission(&perms, attr, access) == 0) return(0); /* see if we have a DN match */ if (aci_get_part(aci, 3, '#', &bv) < 0) return(0); if (aci_get_part(aci, 4, '#', &sdn) < 0) return(0); if (aci_strbvcmp( "access-id", &bv ) == 0) { subjdn = aci_bvstrdup(&sdn); if (subjdn == NULL) return(0); rc = 0; if ( dn_normalize(subjdn) != NULL ) rc = (strcasecmp(op->o_ndn, subjdn) == 0); ch_free(subjdn); return(rc); } if (aci_strbvcmp( "self", &bv ) == 0) { return(strcasecmp(op->o_ndn, edn) == 0); } if (aci_strbvcmp( "group", &bv ) == 0) { return(aci_group_member(&sdn, "groupOfNames", "member", be, e, op, edn, matches)); } if (aci_strbvcmp( "role", &bv ) == 0) { return(aci_group_member(&sdn, "organizationalRole", "roleOccupant", be, e, op, edn, matches)); } return(0); } #endif /* SLAPD_ACI_ENABLED */ static void string_expand( char *newbuf, int bufsiz, char *pat, char *match, regmatch_t *matches) { int size; char *sp; char *dp; int flag; size = 0; newbuf[0] = '\0'; flag = 0; for ( dp = newbuf, sp = pat; size < bufsiz && *sp ; sp++) { /* did we previously see a $ */ if (flag) { if (*sp == '$') { *dp++ = '$'; size++; } else if (*sp >= '0' && *sp <= '9' ) { int n; int i; int l; n = *sp - '0'; *dp = '\0'; i = matches[n].rm_so; l = matches[n].rm_eo; for ( ; size < 512 && i < l; size++, i++ ) { *dp++ = match[i]; size++; } *dp = '\0'; } flag = 0; } else { if (*sp == '$') { flag = 1; } else { *dp++ = *sp; size++; } } } *dp = '\0'; Debug( LDAP_DEBUG_TRACE, "=> string_expand: pattern: %s\n", pat, 0, 0 ); Debug( LDAP_DEBUG_TRACE, "=> string_expand: expanded: %s\n", newbuf, 0, 0 ); } static int regex_matches( char *pat, /* pattern to expand and match against */ char *str, /* string to match against pattern */ char *buf, /* buffer with $N expansion variables */ regmatch_t *matches /* offsets in buffer for $N expansion variables */ ) { regex_t re; char newbuf[512]; int rc; if(str == NULL) str = ""; string_expand(newbuf, sizeof(newbuf), pat, buf, matches); if (( rc = regcomp(&re, newbuf, REG_EXTENDED|REG_ICASE))) { char error[512]; regerror(rc, &re, error, sizeof(error)); Debug( LDAP_DEBUG_TRACE, "compile( \"%s\", \"%s\") failed %s\n", pat, str, error ); return( 0 ); } rc = regexec(&re, str, 0, NULL, 0); regfree( &re ); Debug( LDAP_DEBUG_TRACE, "=> regex_matches: string: %s\n", str, 0, 0 ); Debug( LDAP_DEBUG_TRACE, "=> regex_matches: rc: %d %s\n", rc, !rc ? "matches" : "no matches", 0 ); return( !rc ); }