Check that we have enough padding characters.

[openssl.git] / crypto / evp / digest.c

diff --git a/crypto/evp/digest.c b/crypto/evp/digest.c
index 0b1af6f3c6c2ff7ba18501554aa2550cd431ae2e..aee8127d00574c5d34ce88a2e59498fcf6a1b8f5 100644 (file)
--- a/crypto/evp/digest.c
+++ b/crypto/evp/digest.c
@@ -1,4 +1,3 @@
-/* crypto/evp/digest.c */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -113,9 +112,7 @@
 #include "internal/cryptlib.h"
 #include <openssl/objects.h>
 #include <openssl/evp.h>
-#ifndef OPENSSL_NO_ENGINE
-# include <openssl/engine.h>
-#endif
+#include <openssl/engine.h>
 #include "internal/evp_int.h"
 #include "evp_locl.h"
 
@@ -138,12 +135,7 @@ int EVP_MD_CTX_reset(EVP_MD_CTX *ctx)
     }
     EVP_PKEY_CTX_free(ctx->pctx);
 #ifndef OPENSSL_NO_ENGINE
-    if (ctx->engine)
-        /*
-         * The EVP_MD we used belongs to an ENGINE, release the functional
-         * reference we held for this reason.
-         */
-        ENGINE_finish(ctx->engine);
+    ENGINE_finish(ctx->engine);
 #endif
     memset(ctx, 0, sizeof(*ctx));
 
@@ -175,7 +167,7 @@ int EVP_DigestInit_ex(EVP_MD_CTX *ctx, const EVP_MD *type, ENGINE *impl)
      * Whether it's nice or not, "Inits" can be used on "Final"'d contexts so
      * this context may already have an ENGINE! Try to avoid releasing the
      * previous handle, re-querying for an ENGINE, and having a
-     * reinitialisation, when it may all be unecessary.
+     * reinitialisation, when it may all be unnecessary.
      */
     if (ctx->engine && ctx->digest && (!type ||
                                        (type
@@ -188,21 +180,21 @@ int EVP_DigestInit_ex(EVP_MD_CTX *ctx, const EVP_MD *type, ENGINE *impl)
          * previous check attempted to avoid this if the same ENGINE and
          * EVP_MD could be used).
          */
-        if (ctx->engine)
-            ENGINE_finish(ctx->engine);
-        if (impl) {
+        ENGINE_finish(ctx->engine);
+        if (impl != NULL) {
             if (!ENGINE_init(impl)) {
                 EVPerr(EVP_F_EVP_DIGESTINIT_EX, EVP_R_INITIALIZATION_ERROR);
                 return 0;
             }
-        } else
+        } else {
             /* Ask if an ENGINE is reserved for this job */
             impl = ENGINE_get_digest_engine(type->type);
-        if (impl) {
+        }
+        if (impl != NULL) {
             /* There's an ENGINE for this job ... (apparently) */
             const EVP_MD *d = ENGINE_get_digest(impl, type->type);
-            if (!d) {
-                /* Same comment from evp_enc.c */
+
+            if (d == NULL) {
                 EVPerr(EVP_F_EVP_DIGESTINIT_EX, EVP_R_INITIALIZATION_ERROR);
                 ENGINE_finish(impl);
                 return 0;
@@ -225,12 +217,14 @@ int EVP_DigestInit_ex(EVP_MD_CTX *ctx, const EVP_MD *type, ENGINE *impl)
     }
 #endif
     if (ctx->digest != type) {
-        if (ctx->digest && ctx->digest->ctx_size)
+        if (ctx->digest && ctx->digest->ctx_size) {
             OPENSSL_free(ctx->md_data);
+            ctx->md_data = NULL;
+        }
         ctx->digest = type;
         if (!(ctx->flags & EVP_MD_CTX_FLAG_NO_INIT) && type->ctx_size) {
             ctx->update = type->update;
-            ctx->md_data = OPENSSL_malloc(type->ctx_size);
+            ctx->md_data = OPENSSL_zalloc(type->ctx_size);
             if (ctx->md_data == NULL) {
                 EVPerr(EVP_F_EVP_DIGESTINIT_EX, ERR_R_MALLOC_FAILURE);
                 return 0;
@@ -312,6 +306,13 @@ int EVP_MD_CTX_copy_ex(EVP_MD_CTX *out, const EVP_MD_CTX *in)
     EVP_MD_CTX_reset(out);
     memcpy(out, in, sizeof(*out));
 
+    /* Null these variables, since they are getting fixed up
+     * properly below.  Anything else may cause a memleak and/or
+     * double free if any of the memory allocations below fail
+     */
+    out->md_data = NULL;
+    out->pctx = NULL;
+
     if (in->md_data && out->digest->ctx_size) {
         if (tmp_buf)
             out->md_data = tmp_buf;
@@ -345,7 +346,7 @@ int EVP_Digest(const void *data, size_t count,
                unsigned char *md, unsigned int *size, const EVP_MD *type,
                ENGINE *impl)
 {
-    EVP_MD_CTX *ctx = EVP_MD_CTX_create();
+    EVP_MD_CTX *ctx = EVP_MD_CTX_new();
     int ret;
 
     if (ctx == NULL)
@@ -354,7 +355,7 @@ int EVP_Digest(const void *data, size_t count,
     ret = EVP_DigestInit_ex(ctx, type, impl)
         && EVP_DigestUpdate(ctx, data, count)
         && EVP_DigestFinal_ex(ctx, md, size);
-    EVP_MD_CTX_destroy(ctx);
+    EVP_MD_CTX_free(ctx);
 
     return ret;
 }