1 files changed, 40 insertions, 89 deletions

diff --git a/src/lib/libcrypto/asn1/asn1_old_lib.c b/src/lib/libcrypto/asn1/asn1_old_lib.c
index cc9a48f74c..958c15b30c 100644
--- a/src/lib/libcrypto/asn1/asn1_old_lib.c
+++ b/src/lib/libcrypto/asn1/asn1_old_lib.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: asn1_old_lib.c,v 1.1 2021/12/15 18:12:10 jsing Exp $ */
+/* $OpenBSD: asn1_old_lib.c,v 1.2 2021/12/25 07:04:03 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -63,7 +63,8 @@
 #include <openssl/asn1.h>
 #include <openssl/err.h>
 
-static int asn1_get_length(const unsigned char **pp, int *inf, long *rl, int max);
+#include "asn1_locl.h"
+
 static void asn1_put_length(unsigned char **pp, int length);
 
 static int
@@ -96,101 +97,51 @@ int
 ASN1_get_object(const unsigned char **pp, long *plength, int *ptag,
     int *pclass, long omax)
 {
-        int i, ret;
-        long l;
-        const unsigned char *p = *pp;
-        int tag, xclass, inf;
-        long max = omax;
-
-        if (!max)
-                goto err;
-        ret = (*p & V_ASN1_CONSTRUCTED);
-        xclass = (*p & V_ASN1_PRIVATE);
-        i = *p & V_ASN1_PRIMITIVE_TAG;
-        if (i == V_ASN1_PRIMITIVE_TAG) {                /* high-tag */
-                p++;
-                if (--max == 0)
-                        goto err;
-                l = 0;
-                while (*p & 0x80) {
-                        l <<= 7L;
-                        l |= *(p++) & 0x7f;
-                        if (--max == 0)
-                                goto err;
-                        if (l > (INT_MAX >> 7L))
-                                goto err;
-                }
-                l <<= 7L;
-                l |= *(p++) & 0x7f;
-                tag = (int)l;
-                if (--max == 0)
-                        goto err;
-        } else {
-                tag = i;
-                p++;
-                if (--max == 0)
-                        goto err;
+        int constructed, indefinite;
+        uint32_t tag_number, length;
+        uint8_t tag_class;
+        CBS cbs;
+        int ret = 0;
+
+        *pclass = 0;
+        *ptag = 0;
+        *plength = 0;
+
+        CBS_init(&cbs, *pp, omax);
+
+        if (!asn1_get_object_cbs(&cbs, 0, &tag_class, &constructed, &tag_number,
+            &indefinite, &length)) {
+                ASN1error(ASN1_R_HEADER_TOO_LONG);
+                return 0x80;
         }
-        *ptag = tag;
-        *pclass = xclass;
-        if (!asn1_get_length(&p, &inf, plength, (int)max))
-                goto err;
 
-        if (inf && !(ret & V_ASN1_CONSTRUCTED))
-                goto err;
+        if (tag_number > INT_MAX) {
+                ASN1error(ASN1_R_HEADER_TOO_LONG);
+                return 0x80;
+        }
 
-        if (*plength > (omax - (p - *pp))) {
+        /*
+         * API insanity ahead... in this case we add an error to the stack and
+         * signal an error by setting the 8th bit in the return value... but we
+         * still provide all of the decoded data.
+         */
+        if (length > CBS_len(&cbs)) {
                 ASN1error(ASN1_R_TOO_LONG);
-                /* Set this so that even if things are not long enough
-                 * the values are set correctly */
-                ret |= 0x80;
+                ret = 0x80;
         }
-        *pp = p;
-        return (ret | inf);
 
-err:
-        ASN1error(ASN1_R_HEADER_TOO_LONG);
-        return (0x80);
-}
+        *pclass = tag_class << 6;
+        *ptag = tag_number;
+        *plength = length;
 
-static int
-asn1_get_length(const unsigned char **pp, int *inf, long *rl, int max)
-{
-        const unsigned char *p = *pp;
-        unsigned long ret = 0;
-        unsigned int i;
+        *pp = CBS_data(&cbs);
 
-        if (max-- < 1)
-                return (0);
-        if (*p == 0x80) {
-                *inf = 1;
-                ret = 0;
-                p++;
-        } else {
-                *inf = 0;
-                i = *p & 0x7f;
-                if (*(p++) & 0x80) {
-                        if (max < (int)i)
-                                return (0);
-                        /* skip leading zeroes */
-                        while (i && *p == 0) {
-                                p++;
-                                i--;
-                        }
-                        if (i > sizeof(long))
-                                return 0;
-                        while (i-- > 0) {
-                                ret <<= 8L;
-                                ret |= *(p++);
-                        }
-                } else
-                        ret = i;
-        }
-        if (ret > LONG_MAX)
-                return 0;
-        *pp = p;
-        *rl = (long)ret;
-        return (1);
+        if (constructed)
+                ret |= 1 << 5;
+        if (indefinite)
+                ret |= 1;
+
+        return ret;
 }
 
 /* class 0 is constructed