Replace assert() and OPENSSL_assert() calls with proper error return paths.

Careful review, feedback & ok doug@ jsing@

1 files changed, 31 insertions, 14 deletions

diff --git a/src/lib/libcrypto/evp/evp_enc.c b/src/lib/libcrypto/evp/evp_enc.c
index 49ceacefad..42ccfceec9 100644
--- a/src/lib/libcrypto/evp/evp_enc.c
+++ b/src/lib/libcrypto/evp/evp_enc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: evp_enc.c,v 1.25 2014/10/22 13:02:04 jsing Exp $ */
+/* $OpenBSD: evp_enc.c,v 1.26 2015/02/10 09:52:35 miod Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -140,10 +140,6 @@ EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl,
                         const EVP_CIPHER *c =
                             ENGINE_get_cipher(impl, cipher->nid);
                         if (!c) {
-                                /* One positive side-effect of US's export
-                                 * control history, is that we should at least
-                                 * be able to avoid using US mispellings of
-                                 * "initialisation"? */
                                 EVPerr(EVP_F_EVP_CIPHERINIT_EX,
                                     EVP_R_INITIALIZATION_ERROR);
                                 return 0;
@@ -186,9 +182,12 @@ EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl,
 skip_to_init:
 #endif
         /* we assume block size is a power of 2 in *cryptUpdate */
-        OPENSSL_assert(ctx->cipher->block_size == 1 ||
-            ctx->cipher->block_size == 8 ||
-            ctx->cipher->block_size == 16);
+        if (ctx->cipher->block_size != 1 &&
+            ctx->cipher->block_size != 8 &&
+            ctx->cipher->block_size != 16) {
+                EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_BAD_BLOCK_LENGTH);
+                return 0;
+        }
 
         if (!(EVP_CIPHER_CTX_flags(ctx) & EVP_CIPH_CUSTOM_IV)) {
                 switch (EVP_CIPHER_CTX_mode(ctx)) {
@@ -205,8 +204,12 @@ skip_to_init:
 
                 case EVP_CIPH_CBC_MODE:
 
-                        OPENSSL_assert(EVP_CIPHER_CTX_iv_length(ctx) <=
-                            (int)sizeof(ctx->iv));
+                        if ((size_t)EVP_CIPHER_CTX_iv_length(ctx) >
+                            sizeof(ctx->iv)) {
+                                EVPerr(EVP_F_EVP_CIPHERINIT_EX,
+                                    EVP_R_IV_TOO_LARGE);
+                                return 0;
+                        }
                         if (iv)
                                 memcpy(ctx->oiv, iv,
                                     EVP_CIPHER_CTX_iv_length(ctx));
@@ -325,7 +328,11 @@ EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
         }
         i = ctx->buf_len;
         bl = ctx->cipher->block_size;
-        OPENSSL_assert(bl <= (int)sizeof(ctx->buf));
+        if ((size_t)bl > sizeof(ctx->buf)) {
+                EVPerr(EVP_F_EVP_ENCRYPTUPDATE, EVP_R_BAD_BLOCK_LENGTH);
+                *outl = 0;
+                return 0;
+        }
         if (i != 0) {
                 if (i + inl < bl) {
                         memcpy(&(ctx->buf[i]), in, inl);
@@ -383,7 +390,10 @@ EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
         }
 
         b = ctx->cipher->block_size;
-        OPENSSL_assert(b <= sizeof ctx->buf);
+        if (b > sizeof ctx->buf) {
+                EVPerr(EVP_F_EVP_ENCRYPTFINAL_EX, EVP_R_BAD_BLOCK_LENGTH);
+                return 0;
+        }
         if (b == 1) {
                 *outl = 0;
                 return 1;
@@ -437,7 +447,10 @@ EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
                 return EVP_EncryptUpdate(ctx, out, outl, in, inl);
 
         b = ctx->cipher->block_size;
-        OPENSSL_assert(b <= sizeof ctx->final);
+        if (b > sizeof ctx->final) {
+                EVPerr(EVP_F_EVP_DECRYPTUPDATE, EVP_R_BAD_BLOCK_LENGTH);
+                return 0;
+        }
 
         if (ctx->final_used) {
                 memcpy(out, ctx->final, b);
@@ -506,7 +519,11 @@ EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
                             EVP_R_WRONG_FINAL_BLOCK_LENGTH);
                         return (0);
                 }
-                OPENSSL_assert(b <= sizeof ctx->final);
+                if (b > sizeof ctx->final) {
+                        EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,
+                            EVP_R_BAD_BLOCK_LENGTH);
+                        return 0;
+                }
                 n = ctx->final[b - 1];
                 if (n == 0 || n > (int)b) {
                         EVPerr(EVP_F_EVP_DECRYPTFINAL_EX, EVP_R_BAD_DECRYPT);