Add checks to X509_NAME_oneline()

Sanity check field lengths and sums to avoid potential overflows and reject
excessively large X509_NAME structures.

Issue reported by Guido Vranken.

Reviewed-by: Matt Caswell <matt@openssl.org>
(cherry picked from commit 9b08619cb45e75541809b1154c90e1a00450e537)

Conflicts:
	crypto/x509/x509.h
	crypto/x509/x509_err.c

diff --git a/crypto/x509/x509.h b/crypto/x509/x509.h
index a4911741005e55c047ec9f5173737c236e7a5b29..bd600de43107edbc1a63129330b7c63d27a261de 100644 (file)
--- a/crypto/x509/x509.h
+++ b/crypto/x509/x509.h
@@ -1281,6 +1281,7 @@ void ERR_load_X509_strings(void);
 # define X509_R_LOADING_CERT_DIR                          103
 # define X509_R_LOADING_DEFAULTS                          104
 # define X509_R_METHOD_NOT_SUPPORTED                      124
+# define X509_R_NAME_TOO_LONG                             134
 # define X509_R_NO_CERT_SET_FOR_US_TO_VERIFY              105
 # define X509_R_PUBLIC_KEY_DECODE_ERROR                   125
 # define X509_R_PUBLIC_KEY_ENCODE_ERROR                   126

diff --git a/crypto/x509/x509_err.c b/crypto/x509/x509_err.c
index 61a19f74109b0d6315a80b1468e26ab6b9fb0f57..a2b8b7fc358fe08df7de64f73da5c81d0485655b 100644 (file)
--- a/crypto/x509/x509_err.c
+++ b/crypto/x509/x509_err.c
@@ -145,6 +145,7 @@ static ERR_STRING_DATA X509_str_reasons[] = {
     {ERR_REASON(X509_R_LOADING_CERT_DIR), "loading cert dir"},
     {ERR_REASON(X509_R_LOADING_DEFAULTS), "loading defaults"},
     {ERR_REASON(X509_R_METHOD_NOT_SUPPORTED), "method not supported"},
+    {ERR_REASON(X509_R_NAME_TOO_LONG), "name too long"},
     {ERR_REASON(X509_R_NO_CERT_SET_FOR_US_TO_VERIFY),
      "no cert set for us to verify"},
     {ERR_REASON(X509_R_PUBLIC_KEY_DECODE_ERROR), "public key decode error"},

diff --git a/crypto/x509/x509_obj.c b/crypto/x509/x509_obj.c
index 500c9dfa543bb8cc9bd1ab44d0974aa38ff72b36..f7daac25e9d2435fce82880cfa4dbcb75eef750c 100644 (file)
--- a/crypto/x509/x509_obj.c
+++ b/crypto/x509/x509_obj.c
@@ -63,6 +63,13 @@
 #include <openssl/x509.h>
 #include <openssl/buffer.h>
 
+/*
+ * Limit to ensure we don't overflow: much greater than
+ * anything enountered in practice.
+ */
+
+#define NAME_ONELINE_MAX    (1024 * 1024)
+
 char *X509_NAME_oneline(X509_NAME *a, char *buf, int len)
 {
     X509_NAME_ENTRY *ne;
@@ -112,6 +119,10 @@ char *X509_NAME_oneline(X509_NAME *a, char *buf, int len)
 
         type = ne->value->type;
         num = ne->value->length;
+        if (num > NAME_ONELINE_MAX) {
+            X509err(X509_F_X509_NAME_ONELINE, X509_R_NAME_TOO_LONG);
+            goto end;
+        }
         q = ne->value->data;
 #ifdef CHARSET_EBCDIC
         if (type == V_ASN1_GENERALSTRING ||
@@ -156,6 +167,10 @@ char *X509_NAME_oneline(X509_NAME *a, char *buf, int len)
 
         lold = l;
         l += 1 + l1 + 1 + l2;
+        if (l > NAME_ONELINE_MAX) {
+            X509err(X509_F_X509_NAME_ONELINE, X509_R_NAME_TOO_LONG);
+            goto end;
+        }
         if (b != NULL) {
             if (!BUF_MEM_grow(b, l + 1))
                 goto err;
@@ -208,7 +223,7 @@ char *X509_NAME_oneline(X509_NAME *a, char *buf, int len)
     return (p);
  err:
     X509err(X509_F_X509_NAME_ONELINE, ERR_R_MALLOC_FAILURE);
-    if (b != NULL)
-        BUF_MEM_free(b);
+ end:
+    BUF_MEM_free(b);
     return (NULL);
 }