diff options
Diffstat (limited to 'source4/auth/kerberos/kerberos.c')
| -rw-r--r-- | source4/auth/kerberos/kerberos.c | 672 |
1 files changed, 0 insertions, 672 deletions
diff --git a/source4/auth/kerberos/kerberos.c b/source4/auth/kerberos/kerberos.c index 8c82ae780e..31e0c71c55 100644 --- a/source4/auth/kerberos/kerberos.c +++ b/source4/auth/kerberos/kerberos.c @@ -167,677 +167,5 @@ kerb_prompter(krb5_context ctx, void *data, return 0; } -/* - simulate a kinit, putting the tgt in the given credentials cache. - If cache_name == NULL place in default cache location. - - Orignally by remus@snapserver.com -*/ -int kerberos_kinit_password(const char *principal, - const char *password, - int time_offset, - time_t *expire_time, - const char *cache_name, - time_t *kdc_time) -{ - int code; - krb5_context ctx = NULL; - krb5_ccache cc = NULL; - - if ((code = krb5_init_context(&ctx))) - return code; - - if (time_offset != 0) { - krb5_set_real_time(ctx, time(NULL) + time_offset, 0); - } - - if ((code = krb5_cc_resolve(ctx, cache_name ? - cache_name : krb5_cc_default_name(ctx), &cc))) { - krb5_free_context(ctx); - return code; - } - - code = kerberos_kinit_password_cc(ctx, cc, principal, password, expire_time, kdc_time); - - krb5_cc_close(ctx, cc); - krb5_free_context(ctx); - - return code; -} - -/* run kinit to setup our ccache */ -int ads_kinit_password(struct ads_struct *ads) -{ - char *s; - int ret; - - if (asprintf(&s, "%s@%s", ads->auth.user_name, ads->auth.realm) == -1) { - return KRB5_CC_NOMEM; - } - - if (!ads->auth.password) { - return KRB5_LIBOS_CANTREADPWD; - } - - ret = kerberos_kinit_password(s, ads->auth.password, ads->auth.time_offset, - &ads->auth.expire, NULL, NULL); - - if (ret) { - DEBUG(0,("kerberos_kinit_password %s failed: %s\n", - s, error_message(ret))); - } - free(s); - return ret; -} - -int ads_kdestroy(const char *cc_name) -{ - krb5_error_code code; - krb5_context ctx = NULL; - krb5_ccache cc = NULL; - - if ((code = krb5_init_context (&ctx))) { - DEBUG(3, ("ads_kdestroy: kdb5_init_context failed: %s\n", - error_message(code))); - return code; - } - - if (!cc_name) { - if ((code = krb5_cc_default(ctx, &cc))) { - krb5_free_context(ctx); - return code; - } - } else { - if ((code = krb5_cc_resolve(ctx, cc_name, &cc))) { - DEBUG(3, ("ads_kdestroy: krb5_cc_resolve failed: %s\n", - error_message(code))); - krb5_free_context(ctx); - return code; - } - } - - if ((code = krb5_cc_destroy (ctx, cc))) { - DEBUG(3, ("ads_kdestroy: krb5_cc_destroy failed: %s\n", - error_message(code))); - } - - krb5_free_context (ctx); - return code; -} - -/************************************************************************ - Routine to fetch the salting principal for a service. Active - Directory may use a non-obvious principal name to generate the salt - when it determines the key to use for encrypting tickets for a service, - and hopefully we detected that when we joined the domain. - ************************************************************************/ - -static char *kerberos_secrets_fetch_salting_principal(const char *service, int enctype) -{ - char *ret = NULL; - -#if 0 - asprintf(&key, "%s/%s/enctype=%d", SECRETS_SALTING_PRINCIPAL, service, enctype); - if (!key) { - return NULL; - } - ret = (char *)secrets_fetch(key, NULL); - SAFE_FREE(key); -#endif - return ret; -} - -/************************************************************************ - Routine to get the salting principal for this service. Active - Directory may use a non-obvious principal name to generate the salt - when it determines the key to use for encrypting tickets for a service, - and hopefully we detected that when we joined the domain. - Caller must free if return is not null. - ************************************************************************/ - -krb5_principal kerberos_fetch_salt_princ_for_host_princ(krb5_context context, - krb5_principal host_princ, - int enctype) -{ - char *unparsed_name = NULL, *salt_princ_s = NULL; - krb5_principal ret_princ = NULL; - - if (krb5_unparse_name(context, host_princ, &unparsed_name) != 0) { - return (krb5_principal)NULL; - } - - if ((salt_princ_s = kerberos_secrets_fetch_salting_principal(unparsed_name, enctype)) == NULL) { - krb5_free_unparsed_name(context, unparsed_name); - return (krb5_principal)NULL; - } - - if (krb5_parse_name(context, salt_princ_s, &ret_princ) != 0) { - krb5_free_unparsed_name(context, unparsed_name); - SAFE_FREE(salt_princ_s); - return (krb5_principal)NULL; - } - krb5_free_unparsed_name(context, unparsed_name); - SAFE_FREE(salt_princ_s); - return ret_princ; -} - -/************************************************************************ - Routine to set the salting principal for this service. Active - Directory may use a non-obvious principal name to generate the salt - when it determines the key to use for encrypting tickets for a service, - and hopefully we detected that when we joined the domain. - Setting principal to NULL deletes this entry. - ************************************************************************/ - - BOOL kerberos_secrets_store_salting_principal(const char *service, - int enctype, - const char *principal) -{ - char *key = NULL; - BOOL ret = False; - krb5_context context = NULL; - krb5_principal princ = NULL; - char *princ_s = NULL; - char *unparsed_name = NULL; - - krb5_init_context(&context); - if (!context) { - return False; - } - if (strchr_m(service, '@')) { - asprintf(&princ_s, "%s", service); - } else { - asprintf(&princ_s, "%s@%s", service, lp_realm()); - } - - if (krb5_parse_name(context, princ_s, &princ) != 0) { - goto out; - - } - if (krb5_unparse_name(context, princ, &unparsed_name) != 0) { - goto out; - } - - asprintf(&key, "%s/%s/enctype=%d", SECRETS_SALTING_PRINCIPAL, unparsed_name, enctype); - if (!key) { - goto out; - } - -#if 0 - if ((principal != NULL) && (strlen(principal) > 0)) { - ret = secrets_store(key, principal, strlen(principal) + 1); - } else { - ret = secrets_delete(key); - } -#endif - - out: - - SAFE_FREE(key); - SAFE_FREE(princ_s); - - if (unparsed_name) { - krb5_free_unparsed_name(context, unparsed_name); - } - if (context) { - krb5_free_context(context); - } - - return ret; -} - -/************************************************************************ - Routine to get initial credentials as a service ticket for the local machine. - Returns a buffer initialized with krb5_mk_req_extended. - ************************************************************************/ - -static krb5_error_code get_service_ticket(krb5_context ctx, - krb5_ccache ccache, - const char *service_principal, - int enctype, - krb5_data *p_outbuf) -{ - krb5_creds creds, *new_creds = NULL; - char *service_s = NULL; - char *machine_account = NULL, *password = NULL; - krb5_data in_data; - krb5_auth_context auth_context = NULL; - krb5_error_code err = 0; - - ZERO_STRUCT(creds); - - asprintf(&machine_account, "%s$@%s", lp_netbios_name(), lp_realm()); - if (machine_account == NULL) { - goto out; - } - password = secrets_fetch_machine_password(lp_workgroup()); - if (password == NULL) { - goto out; - } - if ((err = kerberos_kinit_password(machine_account, password, 0, NULL, LIBADS_CCACHE_NAME, NULL)) != 0) { - DEBUG(0,("get_service_ticket: kerberos_kinit_password %s@%s failed: %s\n", - machine_account, - lp_realm(), - error_message(err))); - goto out; - } - - /* Ok - the above call has gotten a TGT. Now we need to get a service - ticket to ourselves. */ - - /* Set up the enctype and client and server principal fields for krb5_get_credentials. */ - kerberos_set_creds_enctype(&creds, enctype); - - if ((err = krb5_cc_get_principal(ctx, ccache, &creds.client))) { - DEBUG(3, ("get_service_ticket: krb5_cc_get_principal failed: %s\n", - error_message(err))); - goto out; - } - - if (strchr_m(service_principal, '@')) { - asprintf(&service_s, "%s", service_principal); - } else { - asprintf(&service_s, "%s@%s", service_principal, lp_realm()); - } - - if ((err = krb5_parse_name(ctx, service_s, &creds.server))) { - DEBUG(0,("get_service_ticket: krb5_parse_name %s failed: %s\n", - service_s, error_message(err))); - goto out; - } - - if ((err = krb5_get_credentials(ctx, 0, ccache, &creds, &new_creds))) { - DEBUG(5,("get_service_ticket: krb5_get_credentials for %s enctype %d failed: %s\n", - service_s, enctype, error_message(err))); - goto out; - } - - memset(&in_data, '\0', sizeof(in_data)); - if ((err = krb5_mk_req_extended(ctx, &auth_context, 0, &in_data, - new_creds, p_outbuf)) != 0) { - DEBUG(0,("get_service_ticket: krb5_mk_req_extended failed: %s\n", - error_message(err))); - goto out; - } - - out: - - if (auth_context) { - krb5_auth_con_free(ctx, auth_context); - } - if (new_creds) { - krb5_free_creds(ctx, new_creds); - } - if (creds.server) { - krb5_free_principal(ctx, creds.server); - } - if (creds.client) { - krb5_free_principal(ctx, creds.client); - } - - SAFE_FREE(service_s); - SAFE_FREE(password); - SAFE_FREE(machine_account); - return err; -} - -/************************************************************************ - Check if the machine password can be used in conjunction with the salting_principal - to generate a key which will successfully decrypt the AP_REQ already - gotten as a message to the local machine. - ************************************************************************/ - -static BOOL verify_service_password(krb5_context ctx, - int enctype, - const char *salting_principal, - krb5_data *in_data) -{ - BOOL ret = False; - krb5_principal salting_kprinc = NULL; - krb5_ticket *ticket = NULL; - krb5_keyblock key; - krb5_data passdata; - char *salting_s = NULL; - char *password = NULL; - krb5_auth_context auth_context = NULL; - krb5_error_code err; - - memset(&passdata, '\0', sizeof(passdata)); - memset(&key, '\0', sizeof(key)); - - password = secrets_fetch_machine_password(lp_workgroup()); - if (password == NULL) { - goto out; - } - - if (strchr_m(salting_principal, '@')) { - asprintf(&salting_s, "%s", salting_principal); - } else { - asprintf(&salting_s, "%s@%s", salting_principal, lp_realm()); - } - - if ((err = krb5_parse_name(ctx, salting_s, &salting_kprinc))) { - DEBUG(0,("verify_service_password: krb5_parse_name %s failed: %s\n", - salting_s, error_message(err))); - goto out; - } - - passdata.length = strlen(password); - passdata.data = (char*)password; - if ((err = create_kerberos_key_from_string_direct(ctx, salting_kprinc, &passdata, &key, enctype))) { - DEBUG(0,("verify_service_password: create_kerberos_key_from_string %d failed: %s\n", - enctype, error_message(err))); - goto out; - } - - if ((err = krb5_auth_con_init(ctx, &auth_context)) != 0) { - DEBUG(0,("verify_service_password: krb5_auth_con_init failed %s\n", error_message(err))); - goto out; - } - - if ((err = krb5_auth_con_setuseruserkey(ctx, auth_context, &key)) != 0) { - DEBUG(0,("verify_service_password: krb5_auth_con_setuseruserkey failed %s\n", error_message(err))); - goto out; - } - - if (!(err = krb5_rd_req(ctx, &auth_context, in_data, NULL, NULL, NULL, &ticket))) { - DEBUG(10,("verify_service_password: decrypted message with enctype %u salt %s!\n", - (unsigned int)enctype, salting_s)); - ret = True; - } - - out: - - memset(&passdata, 0, sizeof(passdata)); - krb5_free_keyblock_contents(ctx, &key); - if (ticket != NULL) { - krb5_free_ticket(ctx, ticket); - } - if (salting_kprinc) { - krb5_free_principal(ctx, salting_kprinc); - } - SAFE_FREE(salting_s); - SAFE_FREE(password); - return ret; -} -/************************************************************************ - * - * From the current draft of kerberos-clarifications: - * - * It is not possible to reliably generate a user's key given a pass - * phrase without contacting the KDC, since it will not be known - * whether alternate salt or parameter values are required. - * - * And because our server has a password, we have this exact problem. We - * make multiple guesses as to which principal name provides the salt which - * the KDC is using. - * - ************************************************************************/ - -static void kerberos_derive_salting_principal_for_enctype(const char *service_principal, - krb5_context ctx, - krb5_ccache ccache, - krb5_enctype enctype, - krb5_enctype *enctypes) -{ - char *salting_principals[3] = {NULL, NULL, NULL}, *second_principal = NULL; - krb5_error_code err = 0; - krb5_data outbuf; - int i, j; - - memset(&outbuf, '\0', sizeof(outbuf)); - - /* Check that the service_principal is useful. */ - if ((service_principal == NULL) || (strlen(service_principal) == 0)) { - return; - } - - /* Generate our first guess -- the principal as-given. */ - asprintf(&salting_principals[0], "%s", service_principal); - if ((salting_principals[0] == NULL) || (strlen(salting_principals[0]) == 0)) { - return; - } - - /* Generate our second guess -- the computer's principal, as Win2k3. */ - asprintf(&second_principal, "host/%s.%s", lp_netbios_name(), lp_realm()); - if (second_principal != NULL) { - strlower_m(second_principal); - asprintf(&salting_principals[1], "%s@%s", second_principal, lp_realm()); - SAFE_FREE(second_principal); - } - if ((salting_principals[1] == NULL) || (strlen(salting_principals[1]) == 0)) { - goto out; - } - - /* Generate our third guess -- the computer's principal, as Win2k. */ - asprintf(&second_principal, "HOST/%s", lp_netbios_name()); - if (second_principal != NULL) { - strlower_m(second_principal + 5); - asprintf(&salting_principals[2], "%s@%s", - second_principal, lp_realm()); - SAFE_FREE(second_principal); - } - if ((salting_principals[2] == NULL) || (strlen(salting_principals[2]) == 0)) { - goto out; - } - - /* Get a service ticket for ourselves into our memory ccache. */ - /* This will commonly fail if there is no principal by that name (and we're trying - many names). So don't print a debug 0 error. */ - - if ((err = get_service_ticket(ctx, ccache, service_principal, enctype, &outbuf)) != 0) { - DEBUG(3, ("verify_service_password: get_service_ticket failed: %s\n", - error_message(err))); - goto out; - } - - /* At this point we have a message to ourselves, salted only the KDC knows how. We - have to work out what that salting is. */ - - /* Try and find the correct salting principal. */ - for (i = 0; i < sizeof(salting_principals) / sizeof(salting_principals[i]); i++) { - if (verify_service_password(ctx, enctype, salting_principals[i], &outbuf)) { - break; - } - } - - /* If we failed to get a match, return. */ - if (i >= sizeof(salting_principals) / sizeof(salting_principals[i])) { - goto out; - } - - /* If we succeeded, store the principal for use for all enctypes which - * share the same cipher and string-to-key function. Doing this here - * allows servers which just pass a keytab to krb5_rd_req() to work - * correctly. */ - for (j = 0; enctypes[j] != 0; j++) { - if (enctype != enctypes[j]) { - /* If this enctype isn't compatible with the one which - * we used, skip it. */ - - if (!kerberos_compatible_enctypes(ctx, enctypes[j], enctype)) - continue; - } - /* If the principal which gives us the proper salt is the one - * which we would normally guess, don't bother noting anything - * in the secrets tdb. */ - if (strcmp(service_principal, salting_principals[i]) != 0) { - kerberos_secrets_store_salting_principal(service_principal, - enctypes[j], - salting_principals[i]); - } - } - - out : - - kerberos_free_data_contents(ctx, &outbuf); - SAFE_FREE(salting_principals[0]); - SAFE_FREE(salting_principals[1]); - SAFE_FREE(salting_principals[2]); - SAFE_FREE(second_principal); -} - -/************************************************************************ - Go through all the possible enctypes for this principal. - ************************************************************************/ - -static void kerberos_derive_salting_principal_direct(krb5_context context, - krb5_ccache ccache, - krb5_enctype *enctypes, - char *service_principal) -{ - int i; - - /* Try for each enctype separately, because the rules are - * different for different enctypes. */ - for (i = 0; enctypes[i] != 0; i++) { - /* Delete secrets entry first. */ - kerberos_secrets_store_salting_principal(service_principal, 0, NULL); -#ifdef ENCTYPE_ARCFOUR_HMAC - if (enctypes[i] == ENCTYPE_ARCFOUR_HMAC) { - /* Of course this'll always work, so just save - * ourselves the effort. */ - continue; - } -#endif - /* Try to figure out what's going on with this - * principal. */ - kerberos_derive_salting_principal_for_enctype(service_principal, - context, - ccache, - enctypes[i], - enctypes); - } -} - -/************************************************************************ - Wrapper function for the above. - ************************************************************************/ - -BOOL kerberos_derive_salting_principal(char *service_principal) -{ - krb5_context context = NULL; - krb5_enctype *enctypes = NULL; - krb5_ccache ccache = NULL; - krb5_error_code ret = 0; - - initialize_krb5_error_table(); - if ((ret = krb5_init_context(&context)) != 0) { - DEBUG(1,("kerberos_derive_cifs_salting_principals: krb5_init_context failed. %s\n", - error_message(ret))); - return False; - } - if ((ret = get_kerberos_allowed_etypes(context, &enctypes)) != 0) { - DEBUG(1,("kerberos_derive_cifs_salting_principals: get_kerberos_allowed_etypes failed. %s\n", - error_message(ret))); - goto out; - } - - if ((ret = krb5_cc_resolve(context, LIBADS_CCACHE_NAME, &ccache)) != 0) { - DEBUG(3, ("get_service_ticket: krb5_cc_resolve for %s failed: %s\n", - LIBADS_CCACHE_NAME, error_message(ret))); - goto out; - } - - kerberos_derive_salting_principal_direct(context, ccache, enctypes, service_principal); - - out: - if (enctypes) { - free_kerberos_etypes(context, enctypes); - } - if (ccache) { - krb5_cc_destroy(context, ccache); - } - if (context) { - krb5_free_context(context); - } - - return ret ? False : True; -} - -/************************************************************************ - Core function to try and determine what salt is being used for any keytab - keys. - ************************************************************************/ - -BOOL kerberos_derive_cifs_salting_principals(void) -{ - fstring my_fqdn; - char *service = NULL; - krb5_context context = NULL; - krb5_enctype *enctypes = NULL; - krb5_ccache ccache = NULL; - krb5_error_code ret = 0; - BOOL retval = False; - - initialize_krb5_error_table(); - if ((ret = krb5_init_context(&context)) != 0) { - DEBUG(1,("kerberos_derive_cifs_salting_principals: krb5_init_context failed. %s\n", - error_message(ret))); - return False; - } - if ((ret = get_kerberos_allowed_etypes(context, &enctypes)) != 0) { - DEBUG(1,("kerberos_derive_cifs_salting_principals: get_kerberos_allowed_etypes failed. %s\n", - error_message(ret))); - goto out; - } - - if ((ret = krb5_cc_resolve(context, LIBADS_CCACHE_NAME, &ccache)) != 0) { - DEBUG(3, ("get_service_ticket: krb5_cc_resolve for %s failed: %s\n", - LIBADS_CCACHE_NAME, error_message(ret))); - goto out; - } - - if (asprintf(&service, "%s$", lp_netbios_name()) != -1) { - strlower_m(service); - kerberos_derive_salting_principal_direct(context, ccache, enctypes, service); - SAFE_FREE(service); - } - if (asprintf(&service, "cifs/%s", lp_netbios_name()) != -1) { - strlower_m(service); - kerberos_derive_salting_principal_direct(context, ccache, enctypes, service); - SAFE_FREE(service); - } - if (asprintf(&service, "host/%s", lp_netbios_name()) != -1) { - strlower_m(service); - kerberos_derive_salting_principal_direct(context, ccache, enctypes, service); - SAFE_FREE(service); - } - if (asprintf(&service, "cifs/%s.%s", lp_netbios_name(), lp_realm()) != -1) { - strlower_m(service); - kerberos_derive_salting_principal_direct(context, ccache, enctypes, service); - SAFE_FREE(service); - } - if (asprintf(&service, "host/%s.%s", lp_netbios_name(), lp_realm()) != -1) { - strlower_m(service); - kerberos_derive_salting_principal_direct(context, ccache, enctypes, service); - SAFE_FREE(service); - } - name_to_fqdn(my_fqdn, lp_netbios_name()); - if (asprintf(&service, "cifs/%s", my_fqdn) != -1) { - strlower_m(service); - kerberos_derive_salting_principal_direct(context, ccache, enctypes, service); - SAFE_FREE(service); - } - if (asprintf(&service, "host/%s", my_fqdn) != -1) { - strlower_m(service); - kerberos_derive_salting_principal_direct(context, ccache, enctypes, service); - SAFE_FREE(service); - } - - retval = True; - - out: - if (enctypes) { - free_kerberos_etypes(context, enctypes); - } - if (ccache) { - krb5_cc_destroy(context, ccache); - } - if (context) { - krb5_free_context(context); - } - return retval; -} #endif |