1 files changed, 67 insertions, 11 deletions

diff --git a/src/lib/libcrypto/asn1/tasn_dec.c b/src/lib/libcrypto/asn1/tasn_dec.c
index 2426cb6253..c22501fc63 100644
--- a/src/lib/libcrypto/asn1/tasn_dec.c
+++ b/src/lib/libcrypto/asn1/tasn_dec.c
@@ -66,6 +66,7 @@
 #include <openssl/err.h>
 
 static int asn1_check_eoc(unsigned char **in, long len);
+static int asn1_find_end(unsigned char **in, long len, char inf);
 static int asn1_collect(BUF_MEM *buf, unsigned char **in, long len, char inf, int tag, int aclass);
 static int collect_data(BUF_MEM *buf, unsigned char **p, long plen);
 static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass, char *inf, char *cst,
@@ -644,7 +645,7 @@ static int asn1_d2i_ex_primitive(ASN1_VALUE **pval, unsigned char **in, long inl
                 cont = *in;
                 /* If indefinite length constructed find the real end */
                 if(inf) {
-                        if(!asn1_collect(NULL, &p, plen, inf, -1, -1)) goto err;
+                        if(!asn1_find_end(&p, plen, inf)) goto err;
                         len = p - cont;
                 } else {
                         len = p - cont + plen;
@@ -807,12 +808,66 @@ int asn1_ex_c2i(ASN1_VALUE **pval, unsigned char *cont, int len, int utype, char
         return ret;
 }
 
+/* This function finds the end of an ASN1 structure when passed its maximum
+ * length, whether it is indefinite length and a pointer to the content.
+ * This is more efficient than calling asn1_collect because it does not
+ * recurse on each indefinite length header.
+ */
+
+static int asn1_find_end(unsigned char **in, long len, char inf)
+        {
+        int expected_eoc;
+        long plen;
+        unsigned char *p = *in, *q;
+        /* If not indefinite length constructed just add length */
+        if (inf == 0)
+                {
+                *in += len;
+                return 1;
+                }
+        expected_eoc = 1;
+        /* Indefinite length constructed form. Find the end when enough EOCs
+         * are found. If more indefinite length constructed headers
+         * are encountered increment the expected eoc count otherwise justi
+         * skip to the end of the data.
+         */
+        while (len > 0)
+                {
+                if(asn1_check_eoc(&p, len))
+                        {
+                        expected_eoc--;
+                        if (expected_eoc == 0)
+                                break;
+                        len -= 2;
+                        continue;
+                        }
+                q = p;
+                /* Just read in a header: only care about the length */
+                if(!asn1_check_tlen(&plen, NULL, NULL, &inf, NULL, &p, len,
+                                -1, 0, 0, NULL))
+                        {
+                        ASN1err(ASN1_F_ASN1_FIND_END, ERR_R_NESTED_ASN1_ERROR);
+                        return 0;
+                        }
+                if (inf)
+                        expected_eoc++;
+                else
+                        p += plen;
+                len -= p - q;
+                }
+        if (expected_eoc)
+                {
+                ASN1err(ASN1_F_ASN1_FIND_END, ASN1_R_MISSING_EOC);
+                return 0;
+                }
+        *in = p;
+        return 1;
+        }
+
 /* This function collects the asn1 data from a constructred string
  * type into a buffer. The values of 'in' and 'len' should refer
  * to the contents of the constructed type and 'inf' should be set
- * if it is indefinite length. If 'buf' is NULL then we just want
- * to find the end of the current structure: useful for indefinite
- * length constructed stuff.
+ * if it is indefinite length.
  */
 
 static int asn1_collect(BUF_MEM *buf, unsigned char **in, long len, char inf, int tag, int aclass)
@@ -822,11 +877,6 @@ static int asn1_collect(BUF_MEM *buf, unsigned char **in, long len, char inf, in
         char cst, ininf;
         p = *in;
         inf &= 1;
-        /* If no buffer and not indefinite length constructed just pass over the encoded data */
-        if(!buf && !inf) {
-                *in += len;
-                return 1;
-        }
         while(len > 0) {
                 q = p;
                 /* Check for EOC */
@@ -845,9 +895,15 @@ static int asn1_collect(BUF_MEM *buf, unsigned char **in, long len, char inf, in
                 }
                 /* If indefinite length constructed update max length */
                 if(cst) {
-                        if(!asn1_collect(buf, &p, plen, ininf, tag, aclass)) return 0;
+#ifdef OPENSSL_ALLOW_NESTED_ASN1_STRINGS
+                        if (!asn1_collect(buf, &p, plen, ininf, tag, aclass))
+                                return 0;
+#else
+                        ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_NESTED_ASN1_STRING);
+                        return 0;
+#endif
                 } else {
-                        if(!collect_data(buf, &p, plen)) return 0;
+                        if(plen && !collect_data(buf, &p, plen)) return 0;
                 }
                 len -= p - q;
         }