krb5 commit: Add new internal pa-data helpers

https://github.com/krb5/krb5/commit/2d2222850200fd74790aaffcc5b5ce3dbfdb0017
commit 2d2222850200fd74790aaffcc5b5ce3dbfdb0017
Author: Greg Hudson <[email protected]>
Date:   Mon Jun 3 16:12:03 2019 -0400

    Add new internal pa-data helpers
    
    Add a new file with five new internal libkrb5 functions to help manage
    pa-data lists.  Move krb5int_find_pa_data() from fast.c into the new
    file and simplify it slightly.

 src/include/k5-int.h         |   26 ++++++++-
 src/lib/krb5/krb/Makefile.in |    3 +
 src/lib/krb5/krb/fast.c      |   17 ------
 src/lib/krb5/krb/padata.c    |  127 ++++++++++++++++++++++++++++++++++++++++++
 src/lib/krb5/libkrb5.exports |    5 ++
 5 files changed, 160 insertions(+), 18 deletions(-)

diff --git a/src/include/k5-int.h b/src/include/k5-int.h
index 7833d99..3bef20c 100644
--- a/src/include/k5-int.h
+++ b/src/include/k5-int.h
@@ -851,11 +851,35 @@ typedef struct _krb5_cammac {
     krb5_verifier_mac **other_verifiers;
 } krb5_cammac;
 
+void krb5_free_etype_info(krb5_context, krb5_etype_info);
+
 krb5_pa_data *
 krb5int_find_pa_data(krb5_context, krb5_pa_data *const *, krb5_preauthtype);
 /* Does not return a copy; original padata sequence responsible for freeing*/
 
-void krb5_free_etype_info(krb5_context, krb5_etype_info);
+/* Allocate a pa-data object with uninitialized contents of size len.  If len
+ * is 0, set the contents field to NULL. */
+krb5_error_code
+k5_alloc_pa_data(krb5_preauthtype pa_type, size_t len, krb5_pa_data **out);
+
+/* Free a single pa-data object. */
+void
+k5_free_pa_data_element(krb5_pa_data *pa);
+
+/* Without copying, add single element *pa to *list, reallocating as necessary.
+ * If *list is NULL, allocate a new list.  Set *pa to NULL on success. */
+krb5_error_code
+k5_add_pa_data_element(krb5_pa_data ***list, krb5_pa_data **pa);
+
+/* Without copying, add a pa-data element of type pa_type to *list with the
+ * contents in data.  Set *data to empty_data() on success. */
+krb5_error_code
+k5_add_pa_data_from_data(krb5_pa_data ***list, krb5_preauthtype pa_type,
+                         krb5_data *data);
+
+/* Add an empty pa-data element of type pa_type to *list. */
+krb5_error_code
+k5_add_empty_pa_data(krb5_pa_data ***list, krb5_preauthtype pa_type);
 
 #endif /* KRB5_PREAUTH__ */
 /*
diff --git a/src/lib/krb5/krb/Makefile.in b/src/lib/krb5/krb/Makefile.in
index 69b9101..7734a47 100644
--- a/src/lib/krb5/krb/Makefile.in
+++ b/src/lib/krb5/krb/Makefile.in
@@ -77,6 +77,7 @@ STLIBOBJS= \
 	mk_safe.o	\
 	pac.o		\
 	pac_sign.o	\
+	padata.o	\
 	parse.o		\
 	parse_host_string.o	\
 	plugin.o	\
@@ -190,6 +191,7 @@ OBJS=	$(OUTPRE)addr_comp.$(OBJEXT)	\
 	$(OUTPRE)mk_safe.$(OBJEXT)	\
 	$(OUTPRE)pac.$(OBJEXT)		\
 	$(OUTPRE)pac_sign.$(OBJEXT)	\
+	$(OUTPRE)padata.$(OBJEXT)	\
 	$(OUTPRE)parse.$(OBJEXT)	\
 	$(OUTPRE)parse_host_string.$(OBJEXT)	\
 	$(OUTPRE)plugin.$(OBJEXT)	\
@@ -303,6 +305,7 @@ SRCS=	$(srcdir)/addr_comp.c	\
 	$(srcdir)/mk_safe.c	\
 	$(srcdir)/pac.c		\
 	$(srcdir)/pac_sign.c	\
+	$(srcdir)/padata.c	\
 	$(srcdir)/parse.c	\
 	$(srcdir)/parse_host_string.c	\
 	$(srcdir)/plugin.c	\
diff --git a/src/lib/krb5/krb/fast.c b/src/lib/krb5/krb/fast.c
index 4f3e27e..62c9f08 100644
--- a/src/lib/krb5/krb/fast.c
+++ b/src/lib/krb5/krb/fast.c
@@ -618,23 +618,6 @@ krb5int_fast_free_state(krb5_context context,
     free(state);
 }
 
-krb5_pa_data *
-krb5int_find_pa_data(krb5_context context, krb5_pa_data *const *padata,
-                     krb5_preauthtype pa_type)
-{
-    krb5_pa_data * const *tmppa;
-
-    if (padata == NULL)
-        return NULL;
-
-    for (tmppa = padata; *tmppa != NULL; tmppa++) {
-        if ((*tmppa)->pa_type == pa_type)
-            break;
-    }
-
-    return *tmppa;
-}
-
 /*
  * Implement FAST negotiation as specified in RFC 6806 section 11.  If
  * the encrypted part of rep sets the enc-pa-rep flag, look for and
diff --git a/src/lib/krb5/krb/padata.c b/src/lib/krb5/krb/padata.c
new file mode 100644
index 0000000..b307f8b
--- /dev/null
+++ b/src/lib/krb5/krb/padata.c
@@ -0,0 +1,127 @@
+/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
+/* lib/krb5/krb/padata.c - utility functions for krb5_pa_data lists */
+/*
+ * Copyright (C) 2019 by the Massachusetts Institute of Technology.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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
+ * COPYRIGHT HOLDER 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 "k5-int.h"
+
+krb5_pa_data *
+krb5int_find_pa_data(krb5_context context, krb5_pa_data *const *pa_list,
+                     krb5_preauthtype pa_type)
+{
+    krb5_pa_data *const *pa;
+
+    for (pa = pa_list; pa != NULL && *pa != NULL; pa++) {
+        if ((*pa)->pa_type == pa_type)
+            return *pa;
+    }
+    return NULL;
+}
+
+krb5_error_code
+k5_alloc_pa_data(krb5_preauthtype pa_type, size_t len, krb5_pa_data **out)
+{
+    krb5_pa_data *pa;
+    uint8_t *buf = NULL;
+
+    *out = NULL;
+    if (len > 0) {
+        buf = malloc(len);
+        if (buf == NULL)
+            return ENOMEM;
+    }
+    pa = malloc(sizeof(*pa));
+    if (pa == NULL) {
+        free(buf);
+        return ENOMEM;
+    }
+    pa->magic = KV5M_PA_DATA;
+    pa->pa_type = pa_type;
+    pa->length = len;
+    pa->contents = buf;
+    *out = pa;
+    return 0;
+}
+
+void
+k5_free_pa_data_element(krb5_pa_data *pa)
+{
+    if (pa != NULL) {
+        free(pa->contents);
+        free(pa);
+    }
+}
+
+krb5_error_code
+k5_add_pa_data_element(krb5_pa_data ***list, krb5_pa_data **pa)
+{
+    size_t count;
+    krb5_pa_data **newlist;
+
+    for (count = 0; *list != NULL && (*list)[count] != NULL; count++);
+
+    newlist = realloc(*list, (count + 2) * sizeof(*newlist));
+    if (newlist == NULL)
+        return ENOMEM;
+    newlist[count] = *pa;
+    newlist[count + 1] = NULL;
+    *pa = NULL;
+    *list = newlist;
+    return 0;
+}
+
+krb5_error_code
+k5_add_pa_data_from_data(krb5_pa_data ***list, krb5_preauthtype pa_type,
+                         krb5_data *data)
+{
+    krb5_error_code ret;
+    krb5_pa_data *pa;
+
+    ret = k5_alloc_pa_data(pa_type, 0, &pa);
+    if (ret)
+        return ret;
+    pa->contents = (uint8_t *)data->data;
+    pa->length = data->length;
+    ret = k5_add_pa_data_element(list, &pa);
+    if (ret) {
+        free(pa);
+        return ret;
+    }
+    *data = empty_data();
+    return 0;
+}
+
+krb5_error_code
+k5_add_empty_pa_data(krb5_pa_data ***list, krb5_preauthtype pa_type)
+{
+    krb5_data empty = empty_data();
+
+    return k5_add_pa_data_from_data(list, pa_type, &empty);
+}
diff --git a/src/lib/krb5/libkrb5.exports b/src/lib/krb5/libkrb5.exports
index a6d1389..1d124a0 100644
--- a/src/lib/krb5/libkrb5.exports
+++ b/src/lib/krb5/libkrb5.exports
@@ -117,6 +117,10 @@ initialize_krb5_error_table
 initialize_k5e1_error_table
 initialize_kv5m_error_table
 initialize_prof_error_table
+k5_add_empty_pa_data
+k5_add_pa_data_element
+k5_add_pa_data_from_data
+k5_alloc_pa_data
 k5_authind_decode
 k5_build_conf_principals
 k5_ccselect_free_context
@@ -129,6 +133,7 @@ k5_free_cammac
 k5_free_data_ptr_list
 k5_free_otp_tokeninfo
 k5_free_kkdcp_message
+k5_free_pa_data_element
 k5_free_pa_otp_challenge
 k5_free_pa_otp_req
 k5_free_secure_cookie