From 6c2b657bfe6991224c665bc4c8e93fdcad8262b7 Mon Sep 17 00:00:00 2001
From: Michael Rash <mbr@cipherdyne.org>
Date: Thu, 21 Feb 2013 22:44:33 -0500
Subject: [PATCH] [libfko] free dynamically allocated resources for multiple
 libfko fcn calls

---
 lib/fko_decode.c     | 25 ++++++++++++++++++++++++-
 lib/fko_encryption.c |  3 +++
 lib/fko_funcs.c      |  9 ++++++---
 lib/fko_hmac.c       |  3 +++
 4 files changed, 36 insertions(+), 4 deletions(-)

diff --git a/lib/fko_decode.c b/lib/fko_decode.c
index fc5a5ecf..5b1da332 100644
--- a/lib/fko_decode.c
+++ b/lib/fko_decode.c
@@ -98,6 +98,9 @@ fko_decode_spa_data(fko_ctx_t ctx)
     if (ctx->encoded_msg_len - t_size < 0)
         return(FKO_ERROR_INVALID_DATA);
 
+    if(ctx->digest != NULL)
+        free(ctx->digest);
+
     /* Copy the digest into the context and terminate the encoded data
      * at that point so the original digest is not part of the
      * encoded string.
@@ -142,7 +145,6 @@ fko_decode_spa_data(fko_ctx_t ctx)
         case FKO_DIGEST_SHA512:
             sha512_base64(tbuf, (unsigned char*)ctx->encoded_msg, ctx->encoded_msg_len);
             break;
-
     }
 
     /* We give up here if the computed digest does not match the
@@ -166,6 +168,9 @@ fko_decode_spa_data(fko_ctx_t ctx)
         return(FKO_ERROR_INVALID_DATA);
     }
 
+    if(ctx->rand_val != NULL)
+        free(ctx->rand_val);
+
     ctx->rand_val = calloc(1, FKO_RAND_VAL_SIZE+1);
     if(ctx->rand_val == NULL)
     {
@@ -192,6 +197,9 @@ fko_decode_spa_data(fko_ctx_t ctx)
 
     strlcpy(tbuf, ndx, t_size+1);
 
+    if(ctx->username != NULL)
+        free(ctx->username);
+
     ctx->username = malloc(t_size+1); /* Yes, more than we need */
     if(ctx->username == NULL)
     {
@@ -250,6 +258,9 @@ fko_decode_spa_data(fko_ctx_t ctx)
         return(FKO_ERROR_INVALID_DATA);
     }
 
+    if(ctx->version != NULL)
+        free(ctx->version);
+
     ctx->version = malloc(t_size+1);
     if(ctx->version == NULL)
     {
@@ -301,6 +312,9 @@ fko_decode_spa_data(fko_ctx_t ctx)
 
     strlcpy(tbuf, ndx, t_size+1);
 
+    if(ctx->message != NULL)
+        free(ctx->message);
+
     ctx->message = malloc(t_size+1); /* Yes, more than we need */
     if(ctx->message == NULL)
     {
@@ -357,6 +371,9 @@ fko_decode_spa_data(fko_ctx_t ctx)
 
         strlcpy(tbuf, ndx, t_size+1);
 
+        if(ctx->nat_access != NULL)
+            free(ctx->nat_access);
+
         ctx->nat_access = malloc(t_size+1); /* Yes, more than we need */
         if(ctx->nat_access == NULL)
         {
@@ -398,6 +415,9 @@ fko_decode_spa_data(fko_ctx_t ctx)
         {
             strlcpy(tbuf, ndx, t_size+1);
 
+            if(ctx->server_auth != NULL)
+                free(ctx->server_auth);
+
             ctx->server_auth = malloc(t_size+1); /* Yes, more than we need */
             if(ctx->server_auth == NULL)
             {
@@ -442,6 +462,9 @@ fko_decode_spa_data(fko_ctx_t ctx)
             */
             strlcpy(tbuf, ndx, t_size+1);
 
+            if(ctx->server_auth != NULL)
+                free(ctx->server_auth);
+
             ctx->server_auth = malloc(t_size+1); /* Yes, more than we need */
             if(ctx->server_auth == NULL)
             {
diff --git a/lib/fko_encryption.c b/lib/fko_encryption.c
index 19ef1d3c..0a7d1e6b 100644
--- a/lib/fko_encryption.c
+++ b/lib/fko_encryption.c
@@ -149,6 +149,9 @@ _rijndael_decrypt(fko_ctx_t ctx,
         return(FKO_ERROR_INVALID_DATA);
     }
 
+    if(ctx->encoded_msg != NULL)
+        free(ctx->encoded_msg);
+
     /* Create a bucket for the plaintext data and decrypt the message
      * data into it.
     */
diff --git a/lib/fko_funcs.c b/lib/fko_funcs.c
index 15df6cdb..d7237005 100644
--- a/lib/fko_funcs.c
+++ b/lib/fko_funcs.c
@@ -160,9 +160,6 @@ fko_new(fko_ctx_t *r_ctx)
 
     FKO_SET_CTX_INITIALIZED(ctx);
 
-    if(r_ctx != NULL)
-        fko_destroy(*r_ctx);
-
     *r_ctx = ctx;
 
     return(FKO_SUCCESS);
@@ -194,6 +191,9 @@ fko_new_with_data(fko_ctx_t *r_ctx, const char * const enc_msg,
         return(FKO_ERROR_INVALID_DATA);
     }
 
+    if(ctx->encrypted_msg != NULL)
+        free(ctx->encrypted_msg);
+
     /* First, add the data to the context.
     */
     ctx->encrypted_msg     = strdup(enc_msg);
@@ -492,6 +492,9 @@ fko_set_spa_data(fko_ctx_t ctx, const char * const enc_msg)
     if(! is_valid_encoded_msg_len(enc_msg_len))
         return(FKO_ERROR_INVALID_DATA);
 
+    if(ctx->encrypted_msg != NULL)
+        free(ctx->encrypted_msg);
+
     /* First, add the data to the context.
     */
     ctx->encrypted_msg = strdup(enc_msg);
diff --git a/lib/fko_hmac.c b/lib/fko_hmac.c
index 9be7f470..32809385 100644
--- a/lib/fko_hmac.c
+++ b/lib/fko_hmac.c
@@ -166,6 +166,9 @@ int fko_calculate_hmac(fko_ctx_t ctx,
     b64_encode(hmac, hmac_base64, SHA256_DIGEST_LEN);
     strip_b64_eq(hmac_base64);
 
+    if(ctx->msg_hmac != NULL)
+        free(ctx->msg_hmac);
+
     ctx->msg_hmac     = strdup(hmac_base64);
     ctx->msg_hmac_len = strnlen(ctx->msg_hmac, SHA512_DIGEST_STR_LEN);