r20640: Commit part 2/2

Update Heimdal to match current lorikeet-heimdal.  This includes
integrated PAC hooks, so Samba doesn't have to handle this any more.

This also brings in the PKINIT code, hence so many new files.

Andrew Bartlett
(This used to be commit 351f7040f7bb73b9a60b22b564686f7c2f98a729)

1 files changed, 370 insertions, 0 deletions

diff --git a/source4/heimdal/kdc/kx509.c b/source4/heimdal/kdc/kx509.c
new file mode 100644
index 0000000000..d817338f73
--- /dev/null
+++ b/source4/heimdal/kdc/kx509.c
@@ -0,0 +1,370 @@
+/*
+ * Copyright (c) 2006 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. 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 "kdc_locl.h"
+#include <hex.h>
+
+RCSID("$Id: kx509.c,v 1.1 2006/12/28 21:03:53 lha Exp $");
+
+/*
+ *
+ */
+
+krb5_error_code
+_kdc_try_kx509_request(void *ptr, size_t len, Kx509Request *req, size_t *size)
+{
+    if (len < 4)
+	return -1;
+    if (memcmp("\x00\x00\x02\x00", ptr, 4) != 0)
+	return -1;
+    return decode_Kx509Request(((unsigned char *)ptr) + 4, len - 4, req, size);
+}
+
+/*
+ *
+ */
+
+static const char version_2_0[4] = {0 , 0, 2, 0};
+
+static krb5_error_code
+verify_req_hash(krb5_context context, 
+		const Kx509Request *req,
+		krb5_keyblock *key)
+{
+    unsigned char digest[SHA_DIGEST_LENGTH];
+    HMAC_CTX ctx;
+    
+    if (req->pk_hash.length != sizeof(digest)) {
+	krb5_set_error_string(context, "pk-hash have wrong length: %lu",
+			      (unsigned long)req->pk_hash.length);
+	return KRB5KDC_ERR_PREAUTH_FAILED;
+    }
+
+    HMAC_CTX_init(&ctx);
+    HMAC_Init_ex(&ctx, 
+		 key->keyvalue.data, key->keyvalue.length, 
+		 EVP_sha1(), NULL);
+    if (sizeof(digest) != HMAC_size(&ctx))
+	krb5_abortx(context, "runtime error, hmac buffer wrong size in kx509");
+    HMAC_Update(&ctx, version_2_0, sizeof(version_2_0));
+    HMAC_Update(&ctx, req->pk_key.data, req->pk_key.length);
+    HMAC_Final(&ctx, digest, 0);
+    HMAC_CTX_cleanup(&ctx);
+
+    if (memcmp(req->pk_hash.data, digest, sizeof(digest)) != 0) {
+	krb5_set_error_string(context, "pk-hash is not correct");
+	return KRB5KDC_ERR_PREAUTH_FAILED;
+    }
+    return 0;
+}
+
+static krb5_error_code
+calculate_reply_hash(krb5_context context,
+		     krb5_keyblock *key,
+		     Kx509Response *rep)
+{
+    HMAC_CTX ctx;
+    
+    HMAC_CTX_init(&ctx);
+
+    HMAC_Init_ex(&ctx, 
+		 key->keyvalue.data, key->keyvalue.length, 
+		 EVP_sha1(), NULL);
+    rep->hash->length = HMAC_size(&ctx);
+    rep->hash->data = malloc(rep->hash->length);
+    if (rep->hash->data == NULL) {
+	HMAC_CTX_cleanup(&ctx);
+	krb5_set_error_string(context, "out of memory");
+	return ENOMEM;
+    }
+
+    HMAC_Update(&ctx, version_2_0, sizeof(version_2_0));
+    if (rep->error_code) {
+	int32_t t = *rep->error_code;
+	do {
+	    unsigned char p = (t & 0xff);
+	    HMAC_Update(&ctx, &p, 1);
+	    t >>= 8;
+	} while (t);
+    }
+    if (rep->certificate)
+	HMAC_Update(&ctx, rep->certificate->data, rep->certificate->length);
+    if (rep->e_text)
+	HMAC_Update(&ctx, *rep->e_text, strlen(*rep->e_text));
+
+    HMAC_Final(&ctx, rep->hash->data, 0);
+    HMAC_CTX_cleanup(&ctx);
+
+    return 0;
+}
+
+/*
+ * Build a certifate for `principal´ that will expire at `endtime´.
+ */
+
+static krb5_error_code
+build_certificate(krb5_context context, 
+		  krb5_kdc_configuration *config,
+		  const krb5_data *key,
+		  time_t endtime,
+		  krb5_principal principal,
+		  krb5_data *certificate)
+{
+    /* XXX write code here to generate certificates */
+    FILE *in, *out;
+    krb5_error_code ret;
+    const char *program;
+    char *str, *strkey;
+    char tstr[64];
+    pid_t pid;
+
+    snprintf(tstr, sizeof(tstr), "%lu", (unsigned long)endtime);
+
+    ret = base64_encode(key->data, key->length, &strkey);
+    if (ret < 0) {
+	krb5_set_error_string(context, "failed to base64 encode key");
+	return ENOMEM;
+    }
+
+    program = krb5_config_get_string(context,
+				     NULL,
+				     "kdc",
+				     "kx509_cert_program",
+				     NULL);
+    if (program == NULL) {
+	free(strkey);
+	krb5_set_error_string(context, "no certificate program configured");
+	return ENOENT;
+    }
+
+    ret = krb5_unparse_name(context, principal, &str);
+    if (ret) {
+	free(strkey);
+	return ret;
+    }
+
+    pid = pipe_execv(&in, &out, NULL, program, str, tstr, NULL);
+    free(str);
+    if (pid <= 0) {
+	free(strkey);
+	krb5_set_error_string(context, 
+			      "Failed to run the cert program %s",
+			      program);
+	return ret;
+    }
+    fprintf(in, "%s\n", strkey);
+    fclose(in);
+    free(strkey);
+
+    {
+	unsigned buf[1024 * 10];
+	size_t len;
+
+	len = fread(buf, 1, sizeof(buf), out);
+	fclose(out);
+	if(len == 0) {
+	    krb5_set_error_string(context, 
+				  "Certificate program returned no data");
+	    return KRB5KDC_ERR_PREAUTH_FAILED;
+	}
+	ret = krb5_data_copy(certificate, buf, len);
+	if (ret) {
+	    krb5_set_error_string(context, "Failed To copy certificate");
+	    return ret;
+	}
+    }
+    kill(pid, SIGKILL);
+    waitpid(pid, NULL, 0);
+    return 0;
+}
+
+/*
+ *
+ */
+
+krb5_error_code
+_kdc_do_kx509(krb5_context context, 
+	      krb5_kdc_configuration *config,
+	      const Kx509Request *req, krb5_data *reply,
+	      const char *from, struct sockaddr *addr)
+{
+    krb5_error_code ret;
+    krb5_ticket *ticket = NULL;
+    krb5_flags ap_req_options;
+    krb5_auth_context ac = NULL;
+    krb5_keytab id = NULL;
+    krb5_principal sprincipal = NULL, cprincipal = NULL;
+    char *cname = NULL;
+    Kx509Response rep;
+    size_t size;
+    krb5_keyblock *key = NULL;
+
+    krb5_data_zero(reply);
+    memset(&rep, 0, sizeof(rep));
+
+    if(!config->enable_kx509) {
+	kdc_log(context, config, 0, 
+		"Rejected kx509 request (disabled) from %s", from);
+	return KRB5KDC_ERR_POLICY;
+    }
+
+    kdc_log(context, config, 0, "Kx509 request from %s", from);
+
+    ret = krb5_kt_resolve(context, "HDB:", &id);
+    if (ret) {
+	kdc_log(context, config, 0, "Can't open database for digest");
+	goto out;
+    }
+
+    ret = krb5_rd_req(context, 
+		      &ac,
+		      &req->authenticator,
+		      NULL,
+		      id,
+		      &ap_req_options,
+		      &ticket);
+    if (ret)
+	goto out;
+
+    ret = krb5_ticket_get_client(context, ticket, &cprincipal);
+    if (ret)
+	goto out;
+
+    ret = krb5_unparse_name(context, cprincipal, &cname);
+    if (ret)
+	goto out;
+    
+    /* verify server principal */
+
+    ret = krb5_sname_to_principal(context, NULL, "kca_service",
+				  KRB5_NT_UNKNOWN, &sprincipal);
+    if (ret)
+	goto out;
+
+    {
+	krb5_principal principal = NULL;
+
+	ret = krb5_ticket_get_server(context, ticket, &principal);
+	if (ret)
+	    goto out;
+
+	ret = krb5_principal_compare(context, sprincipal, principal);
+	krb5_free_principal(context, principal);
+	if (ret != TRUE) {
+	    ret = KRB5KDC_ERR_SERVER_NOMATCH;
+	    krb5_set_error_string(context, 
+				  "User %s used wrong Kx509 service principal",
+				  cname);
+	    goto out;
+	}
+    }
+    
+    ret = krb5_auth_con_getkey(context, ac, &key);
+    if (ret || key == NULL) {
+	krb5_set_error_string(context, "Kx509 can't get session key");
+	goto out;
+    }
+    
+    ret = verify_req_hash(context, req, key);
+    if (ret)
+	goto out;
+
+    ALLOC(rep.certificate);
+    if (rep.certificate == NULL)
+	goto out;
+    krb5_data_zero(rep.certificate);
+    ALLOC(rep.hash);
+    if (rep.hash == NULL)
+	goto out;
+    krb5_data_zero(rep.hash);
+
+    ret = build_certificate(context, config, &req->pk_key, 
+			    krb5_ticket_get_endtime(context, ticket),
+			    cprincipal, rep.certificate);
+    if (ret)
+	goto out;
+
+    ret = calculate_reply_hash(context, key, &rep);
+    if (ret)
+	goto out;
+
+    /*
+     * Encode reply, [ version | Kx509Response ]
+     */
+
+    {
+	krb5_data data;
+
+	ASN1_MALLOC_ENCODE(Kx509Response, data.data, data.length, &rep,
+			   &size, ret);
+	if (ret) {
+	    krb5_set_error_string(context, "Failed to encode kx509 reply");
+	    goto out;
+	}
+	if (size != data.length)
+	    krb5_abortx(context, "ASN1 internal error");
+
+	ret = krb5_data_alloc(reply, data.length + sizeof(version_2_0));
+	if (ret) {
+	    free(data.data);
+	    goto out;
+	}
+	memcpy(reply->data, version_2_0, sizeof(version_2_0));
+	memcpy(((unsigned char *)reply->data) + sizeof(version_2_0),
+	       data.data, data.length);
+	free(data.data);
+    }
+
+    kdc_log(context, config, 0, "Successful Kx509 request for %s", cname);
+
+out:
+    if (ac)
+	krb5_auth_con_free(context, ac);
+    if (ret)
+	krb5_warn(context, ret, "Kx509 request from %s failed", from);
+    if (ticket)
+	krb5_free_ticket(context, ticket);
+    if (id)
+	krb5_kt_close(context, id);
+    if (sprincipal)
+	krb5_free_principal(context, sprincipal);
+    if (cprincipal)
+	krb5_free_principal(context, cprincipal);
+    if (key)
+	krb5_free_keyblock (context, key);
+    if (cname)
+	free(cname);
+    free_Kx509Response(&rep);
+
+    return 0;
+}