Exemplo n.º 1
0
static krb5_error_code
parse_tgs_rep(krb5_context context,
	      krb5_tkt_creds_context ctx,
	      krb5_data *in,
	      krb5_creds *outcred)
{
    krb5_error_code ret;
    krb5_kdc_rep rep;
    size_t len;
    
    memset(&rep, 0, sizeof(rep));
    memset(outcred, 0, sizeof(*outcred));

    if (ctx->ccache->ops->tgt_rep) {
	return EINVAL;
    }

    if(decode_TGS_REP(in->data, in->length, &rep.kdc_rep, &len) == 0) {
	unsigned eflags = 0;
	
	ret = krb5_copy_principal(context,
				  ctx->next.client,
				  &outcred->client);
	if(ret)
	    return ret;
	ret = krb5_copy_principal(context,
				  ctx->next.server,
				  &outcred->server);
	if(ret)
	    return ret;
	/* this should go someplace else */
	outcred->times.endtime = ctx->in_cred->times.endtime;
	
	if (ctx->kdc_flags.b.constrained_delegation || ctx->impersonate_principal)
	    eflags |= EXTRACT_TICKET_ALLOW_CNAME_MISMATCH;
	
	ret = _krb5_extract_ticket(context,
				   &rep,
				   outcred,
				   &ctx->tgt.session,
				   0,
				   &ctx->tgt.addresses,
				   ctx->nonce,
				   eflags,
				   NULL,
				   _krb5_decrypt_tkt_with_subkey,
				   ctx->subkey);

    } else if(krb5_rd_error(context, in, &rep.error) == 0) {
	ret = krb5_error_from_rd_error(context, &rep.error, ctx->in_cred);
    } else {
	ret = KRB5KRB_AP_ERR_MSG_TYPE;
	krb5_clear_error_message(context);
    }
    krb5_free_kdc_rep(context, &rep);
    return ret;
}
Exemplo n.º 2
0
static krb5_error_code
get_cred_kdc(krb5_context context,
	     krb5_ccache id,
	     krb5_kdc_flags flags,
	     krb5_addresses *addresses,
	     krb5_creds *in_creds,
	     krb5_creds *krbtgt,
	     krb5_principal impersonate_principal,
	     Ticket *second_ticket,
	     krb5_creds *out_creds)
{
    TGS_REQ req;
    krb5_data enc;
    krb5_data resp;
    krb5_kdc_rep rep;
    KRB_ERROR error;
    krb5_error_code ret;
    unsigned nonce;
    krb5_keyblock *subkey = NULL;
    size_t len;
    Ticket second_ticket_data;
    METHOD_DATA padata;

    krb5_data_zero(&resp);
    krb5_data_zero(&enc);
    padata.val = NULL;
    padata.len = 0;

    krb5_generate_random_block(&nonce, sizeof(nonce));
    nonce &= 0xffffffff;

    if(flags.b.enc_tkt_in_skey && second_ticket == NULL){
	ret = decode_Ticket(in_creds->second_ticket.data,
			    in_creds->second_ticket.length,
			    &second_ticket_data, &len);
	if(ret)
	    return ret;
	second_ticket = &second_ticket_data;
    }


    if (impersonate_principal) {
	krb5_crypto crypto;
	PA_S4U2Self self;
	krb5_data data;
	void *buf;
	size_t size;

	self.name = impersonate_principal->name;
	self.realm = impersonate_principal->realm;
	self.auth = estrdup("Kerberos");
	
	ret = _krb5_s4u2self_to_checksumdata(context, &self, &data);
	if (ret) {
	    free(self.auth);
	    goto out;
	}

	ret = krb5_crypto_init(context, &krbtgt->session, 0, &crypto);
	if (ret) {
	    free(self.auth);
	    krb5_data_free(&data);
	    goto out;
	}

	ret = krb5_create_checksum(context,
				   crypto,
				   KRB5_KU_OTHER_CKSUM,
				   0,
				   data.data,
				   data.length,
				   &self.cksum);
	krb5_crypto_destroy(context, crypto);
	krb5_data_free(&data);
	if (ret) {
	    free(self.auth);
	    goto out;
	}

	ASN1_MALLOC_ENCODE(PA_S4U2Self, buf, len, &self, &size, ret);
	free(self.auth);
	free_Checksum(&self.cksum);
	if (ret)
	    goto out;
	if (len != size)
	    krb5_abortx(context, "internal asn1 error");
	
	ret = krb5_padata_add(context, &padata, KRB5_PADATA_FOR_USER, buf, len);
	if (ret)
	    goto out;
    }

    ret = init_tgs_req (context,
			id,
			addresses,
			flags,
			second_ticket,
			in_creds,
			krbtgt,
			nonce,
			&padata,
			&subkey,
			&req);
    if (ret)
	goto out;

    ASN1_MALLOC_ENCODE(TGS_REQ, enc.data, enc.length, &req, &len, ret);
    if (ret)
	goto out;
    if(enc.length != len)
	krb5_abortx(context, "internal error in ASN.1 encoder");

    /* don't free addresses */
    req.req_body.addresses = NULL;
    free_TGS_REQ(&req);

    /*
     * Send and receive
     */
    {
	krb5_sendto_ctx stctx;
	ret = krb5_sendto_ctx_alloc(context, &stctx);
	if (ret)
	    return ret;
	krb5_sendto_ctx_set_func(stctx, _krb5_kdc_retry, NULL);

	ret = krb5_sendto_context (context, stctx, &enc,
				   krbtgt->server->name.name_string.val[1],
				   &resp);
	krb5_sendto_ctx_free(context, stctx);
    }
    if(ret)
	goto out;

    memset(&rep, 0, sizeof(rep));
    if(decode_TGS_REP(resp.data, resp.length, &rep.kdc_rep, &len) == 0) {
	unsigned eflags = 0;

	ret = krb5_copy_principal(context,
				  in_creds->client,
				  &out_creds->client);
	if(ret)
	    goto out2;
	ret = krb5_copy_principal(context,
				  in_creds->server,
				  &out_creds->server);
	if(ret)
	    goto out2;
	/* this should go someplace else */
	out_creds->times.endtime = in_creds->times.endtime;

	/* XXX should do better testing */
	if (flags.b.constrained_delegation || impersonate_principal)
	    eflags |= EXTRACT_TICKET_ALLOW_CNAME_MISMATCH;

	ret = _krb5_extract_ticket(context,
				   &rep,
				   out_creds,
				   &krbtgt->session,
				   NULL,
				   0,
				   &krbtgt->addresses,
				   nonce,
				   eflags,
				   decrypt_tkt_with_subkey,
				   subkey);
    out2:
	krb5_free_kdc_rep(context, &rep);
    } else if(krb5_rd_error(context, &resp, &error) == 0) {
	ret = krb5_error_from_rd_error(context, &error, in_creds);
	krb5_free_error_contents(context, &error);
    } else if(resp.length > 0 && ((char*)resp.data)[0] == 4) {
	ret = KRB5KRB_AP_ERR_V4_REPLY;
	krb5_clear_error_message(context);
    } else {
	ret = KRB5KRB_AP_ERR_MSG_TYPE;
	krb5_clear_error_message(context);
    }

out:
    if (second_ticket == &second_ticket_data)
	free_Ticket(&second_ticket_data);
    free_METHOD_DATA(&padata);
    krb5_data_free(&resp);
    krb5_data_free(&enc);
    if(subkey)
	krb5_free_keyblock(context, subkey);
    return ret;

}
Exemplo n.º 3
0
static krb5_error_code
get_cred_kdc_usage(krb5_context context, 
		   krb5_ccache id, 
		   krb5_kdc_flags flags,
		   krb5_addresses *addresses, 
		   krb5_creds *in_creds, 
		   krb5_creds *krbtgt,
		   krb5_creds *out_creds,
		   krb5_key_usage usage)
{
    TGS_REQ req;
    krb5_data enc;
    krb5_data resp;
    krb5_kdc_rep rep;
    KRB_ERROR error;
    krb5_error_code ret;
    unsigned nonce;
    krb5_keyblock *subkey = NULL;
    size_t len;
    Ticket second_ticket;
    int send_to_kdc_flags = 0;
    
    krb5_data_zero(&resp);
    krb5_data_zero(&enc);

    krb5_generate_random_block(&nonce, sizeof(nonce));
    nonce &= 0xffffffff;
    
    if(flags.b.enc_tkt_in_skey){
	ret = decode_Ticket(in_creds->second_ticket.data, 
			    in_creds->second_ticket.length, 
			    &second_ticket, &len);
	if(ret)
	    return ret;
    }

    ret = init_tgs_req (context,
			id,
			addresses,
			flags,
			flags.b.enc_tkt_in_skey ? &second_ticket : NULL,
			in_creds,
			krbtgt,
			nonce,
			&subkey, 
			&req,
			usage);
    if(flags.b.enc_tkt_in_skey)
	free_Ticket(&second_ticket);
    if (ret)
	goto out;

    ASN1_MALLOC_ENCODE(TGS_REQ, enc.data, enc.length, &req, &len, ret);
    if (ret) 
	goto out;
    if(enc.length != len)
	krb5_abortx(context, "internal error in ASN.1 encoder");

    /* don't free addresses */
    req.req_body.addresses = NULL;
    free_TGS_REQ(&req);

    /*
     * Send and receive
     */
again:
    ret = krb5_sendto_kdc_flags (context, &enc, 
				 &krbtgt->server->name.name_string.val[1],
				 &resp,
				 send_to_kdc_flags);
    if(ret)
	goto out;

    memset(&rep, 0, sizeof(rep));
    if(decode_TGS_REP(resp.data, resp.length, &rep.kdc_rep, &len) == 0){
	ret = krb5_copy_principal(context, 
				  in_creds->client, 
				  &out_creds->client);
	if(ret)
	    goto out;
	ret = krb5_copy_principal(context, 
				  in_creds->server, 
				  &out_creds->server);
	if(ret)
	    goto out;
	/* this should go someplace else */
	out_creds->times.endtime = in_creds->times.endtime;

	ret = _krb5_extract_ticket(context,
				   &rep,
				   out_creds,
				   &krbtgt->session,
				   NULL,
				   KRB5_KU_TGS_REP_ENC_PART_SESSION,
				   &krbtgt->addresses,
				   nonce,
				   TRUE,
				   flags.b.request_anonymous,
				   decrypt_tkt_with_subkey,
				   subkey);
	krb5_free_kdc_rep(context, &rep);
    } else if(krb5_rd_error(context, &resp, &error) == 0) {
	ret = krb5_error_from_rd_error(context, &error, in_creds);
	krb5_free_error_contents(context, &error);

	if (ret == KRB5KRB_ERR_RESPONSE_TOO_BIG && !(send_to_kdc_flags & KRB5_KRBHST_FLAGS_LARGE_MSG)) {
	    send_to_kdc_flags |= KRB5_KRBHST_FLAGS_LARGE_MSG;
	    krb5_data_free(&resp);
	    goto again;
	}
    } else if(resp.data && ((char*)resp.data)[0] == 4) {
	ret = KRB5KRB_AP_ERR_V4_REPLY;
	krb5_clear_error_string(context);
    } else {
	ret = KRB5KRB_AP_ERR_MSG_TYPE;
	krb5_clear_error_string(context);
    }

out:
    krb5_data_free(&resp);
    krb5_data_free(&enc);
    if(subkey){
	krb5_free_keyblock_contents(context, subkey);
	free(subkey);
    }
    return ret;
    
}