Convert asn1_ex_c2i() to CBS.

This allows us to make direct use of c2i_ASN1_OBJECT_cbs().

ok inoguchi@ tb@

3 files changed, 43 insertions, 24 deletions

diff --git a/src/lib/libcrypto/asn1/a_object.c b/src/lib/libcrypto/asn1/a_object.c
index c6e4c77f92..c695499b31 100644
--- a/src/lib/libcrypto/asn1/a_object.c
+++ b/src/lib/libcrypto/asn1/a_object.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: a_object.c,v 1.46 2022/04/10 12:42:33 inoguchi Exp $ */
+/* $OpenBSD: a_object.c,v 1.47 2022/04/23 18:47:08 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -529,9 +529,14 @@ c2i_ASN1_OBJECT_cbs(ASN1_OBJECT **out_aobj, CBS *content)
         size_t data_len;
         CBS cbs;
 
-        if (out_aobj == NULL || *out_aobj != NULL)
+        if (out_aobj == NULL)
                 goto err;
 
+        if (*out_aobj != NULL) {
+                ASN1_OBJECT_free(*out_aobj);
+                *out_aobj = NULL;
+        }
+
         /* Parse and validate OID encoding per X.690 8.19.2. */
         CBS_dup(content, &cbs);
         if (CBS_len(&cbs) == 0) {
diff --git a/src/lib/libcrypto/asn1/asn1_locl.h b/src/lib/libcrypto/asn1/asn1_locl.h
index 756e4070ba..d4ea3a9db8 100644
--- a/src/lib/libcrypto/asn1/asn1_locl.h
+++ b/src/lib/libcrypto/asn1/asn1_locl.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: asn1_locl.h,v 1.24 2022/03/26 14:47:58 jsing Exp $ */
+/* $OpenBSD: asn1_locl.h,v 1.25 2022/04/23 18:47:08 jsing Exp $ */
 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
  * project 2006.
  */
@@ -203,6 +203,7 @@ int asn1_tag2charwidth(int tag);
 
 int i2t_ASN1_OBJECT_internal(const ASN1_OBJECT *aobj, char *buf, int buf_len,
     int no_name);
+int c2i_ASN1_OBJECT_cbs(ASN1_OBJECT **out_aobj, CBS *content);
 ASN1_OBJECT *t2i_ASN1_OBJECT_internal(const char *oid);
 
 __END_HIDDEN_DECLS
diff --git a/src/lib/libcrypto/asn1/tasn_dec.c b/src/lib/libcrypto/asn1/tasn_dec.c
index d475c99676..76dceaabef 100644
--- a/src/lib/libcrypto/asn1/tasn_dec.c
+++ b/src/lib/libcrypto/asn1/tasn_dec.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: tasn_dec.c,v 1.49 2022/03/13 14:58:14 jsing Exp $ */
+/* $OpenBSD: tasn_dec.c,v 1.50 2022/04/23 18:47:08 jsing Exp $ */
 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
  * project 2000.
  */
@@ -95,8 +95,8 @@ static int asn1_template_noexp_d2i(ASN1_VALUE **val, const unsigned char **in,
 static int asn1_d2i_ex_primitive(ASN1_VALUE **pval, const unsigned char **in,
     long len, const ASN1_ITEM *it, int tag, int aclass, char opt,
     ASN1_TLC *ctx);
-static int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *content, int len,
-    int utype, const ASN1_ITEM *it);
+static int asn1_ex_c2i(ASN1_VALUE **pval, CBS *content, int utype,
+    const ASN1_ITEM *it);
 
 static void
 asn1_tlc_invalidate(ASN1_TLC *ctx)
@@ -669,6 +669,7 @@ asn1_d2i_ex_primitive(ASN1_VALUE **pval, const unsigned char **in, long inlen,
         const unsigned char *content = NULL;
         uint8_t *data = NULL;
         size_t data_len = 0;
+        CBS cbs;
         CBB cbb;
         long len;
 
@@ -771,7 +772,10 @@ asn1_d2i_ex_primitive(ASN1_VALUE **pval, const unsigned char **in, long inlen,
         }
 
         /* We now have content length and type: translate into a structure */
-        if (!asn1_ex_c2i(pval, content, len, utype, it))
+        if (len < 0)
+                goto err;
+        CBS_init(&cbs, content, len);
+        if (!asn1_ex_c2i(pval, &cbs, utype, it))
                 goto err;
 
         *in = p;
@@ -784,25 +788,31 @@ asn1_d2i_ex_primitive(ASN1_VALUE **pval, const unsigned char **in, long inlen,
         return ret;
 }
 
-/* Translate ASN1 content octets into a structure */
-
+/* Translate ASN.1 content octets into a structure. */
 static int
-asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *content, int len, int utype,
-    const ASN1_ITEM *it)
+asn1_ex_c2i(ASN1_VALUE **pval, CBS *content, int utype, const ASN1_ITEM *it)
 {
         ASN1_VALUE **opval = NULL;
         ASN1_STRING *stmp;
         ASN1_TYPE *typ = NULL;
         ASN1_INTEGER **tint;
+        ASN1_BOOLEAN *tbool;
+        const uint8_t *p;
+        uint8_t u8val;
         int ret = 0;
 
+        if (CBS_len(content) > INT_MAX)
+                return 0;
+
         if (it->funcs != NULL) {
                 const ASN1_PRIMITIVE_FUNCS *pf = it->funcs;
                 char free_content = 0;
 
                 if (pf->prim_c2i == NULL)
                         return 0;
-                return pf->prim_c2i(pval, content, len, utype, &free_content, it);
+
+                return pf->prim_c2i(pval, CBS_data(content), CBS_len(content),
+                    utype, &free_content, it);
         }
 
         /* If ANY type clear type and set pointer to internal value */
@@ -822,12 +832,12 @@ asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *content, int len, int utype,
         }
         switch (utype) {
         case V_ASN1_OBJECT:
-                if (!c2i_ASN1_OBJECT((ASN1_OBJECT **)pval, &content, len))
+                if (!c2i_ASN1_OBJECT_cbs((ASN1_OBJECT **)pval, content))
                         goto err;
                 break;
 
         case V_ASN1_NULL:
-                if (len) {
+                if (CBS_len(content) != 0) {
                         ASN1error(ASN1_R_NULL_IS_WRONG_LENGTH);
                         goto err;
                 }
@@ -835,25 +845,28 @@ asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *content, int len, int utype,
                 break;
 
         case V_ASN1_BOOLEAN:
-                if (len != 1) {
+                tbool = (ASN1_BOOLEAN *)pval;
+                if (CBS_len(content) != 1) {
                         ASN1error(ASN1_R_BOOLEAN_IS_WRONG_LENGTH);
                         goto err;
-                } else {
-                        ASN1_BOOLEAN *tbool;
-                        tbool = (ASN1_BOOLEAN *)pval;
-                        *tbool = *content;
                 }
+                if (!CBS_get_u8(content, &u8val))
+                        goto err;
+                *tbool = u8val;
                 break;
 
         case V_ASN1_BIT_STRING:
-                if (!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &content, len))
+                p = CBS_data(content);
+                if (!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &p,
+                    CBS_len(content)))
                         goto err;
                 break;
 
         case V_ASN1_INTEGER:
         case V_ASN1_ENUMERATED:
                 tint = (ASN1_INTEGER **)pval;
-                if (!c2i_ASN1_INTEGER(tint, &content, len))
+                p = CBS_data(content);
+                if (!c2i_ASN1_INTEGER(tint, &p, CBS_len(content)))
                         goto err;
                 /* Fixup type to match the expected form */
                 (*tint)->type = utype | ((*tint)->type & V_ASN1_NEG);
@@ -877,11 +890,11 @@ asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *content, int len, int utype,
         case V_ASN1_SET:
         case V_ASN1_SEQUENCE:
         default:
-                if (utype == V_ASN1_BMPSTRING && (len & 1)) {
+                if (utype == V_ASN1_BMPSTRING && (CBS_len(content) & 1)) {
                         ASN1error(ASN1_R_BMPSTRING_IS_WRONG_LENGTH);
                         goto err;
                 }
-                if (utype == V_ASN1_UNIVERSALSTRING && (len & 3)) {
+                if (utype == V_ASN1_UNIVERSALSTRING && (CBS_len(content) & 3)) {
                         ASN1error(ASN1_R_UNIVERSALSTRING_IS_WRONG_LENGTH);
                         goto err;
                 }
@@ -896,7 +909,7 @@ asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *content, int len, int utype,
                         stmp = (ASN1_STRING *)*pval;
                         stmp->type = utype;
                 }
-                if (!ASN1_STRING_set(stmp, content, len)) {
+                if (!ASN1_STRING_set(stmp, CBS_data(content), CBS_len(content))) {
                         ASN1_STRING_free(stmp);
                         *pval = NULL;
                         goto err;