diff --git a/ChangeLog b/ChangeLog
index 0fe3ea709..3b11f4e38 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -7,7 +7,7 @@ Features
    * Added support for GeneralizedTime in X509 parsing
    * Added cert_app program to allow easy reading and
      printing of X509 certificates from file or SSL
-	 connection.
+     connection.
 
 Changes
    * Added const correctness for main code base
@@ -16,11 +16,13 @@ Changes
    * Changed symmetric cipher functions to
      identical interface (returning int result values)
    * Changed ARC4 to use seperate input/output buffer
+   * Added reset function for HMAC context as speed-up
+     for specific use-cases
 
 Bug fixes
    * Fixed bug resulting in failure to send the last
      certificate in the chain in ssl_write_certificate() and
-	 ssl_write_certificate_request() (found by fatbob)
+     ssl_write_certificate_request() (found by fatbob)
    * Added small fixes for compiler warnings on a Mac
      (found by Frank de Brabander)
    * Fixed algorithmic bug in mpi_is_prime() (found by
diff --git a/include/polarssl/md2.h b/include/polarssl/md2.h
index 37eef0a3a..71040eb8d 100644
--- a/include/polarssl/md2.h
+++ b/include/polarssl/md2.h
@@ -112,6 +112,13 @@ void md2_hmac_update( md2_context *ctx, const unsigned char *input, int ilen );
  */
 void md2_hmac_finish( md2_context *ctx, unsigned char output[16] );
 
+/**
+ * \brief          MD2 HMAC context reset
+ *
+ * \param ctx      HMAC context to be reset
+ */
+void md2_hmac_reset( md2_context *ctx );
+
 /**
  * \brief          Output = HMAC-MD2( hmac key, input buffer )
  *
diff --git a/include/polarssl/md4.h b/include/polarssl/md4.h
index c590736bf..24b90ec66 100644
--- a/include/polarssl/md4.h
+++ b/include/polarssl/md4.h
@@ -111,6 +111,13 @@ void md4_hmac_update( md4_context *ctx, const unsigned char *input, int ilen );
  */
 void md4_hmac_finish( md4_context *ctx, unsigned char output[16] );
 
+/**
+ * \brief          MD4 HMAC context reset
+ *
+ * \param ctx      HMAC context to be reset
+ */
+void md4_hmac_reset( md4_context *ctx );
+
 /**
  * \brief          Output = HMAC-MD4( hmac key, input buffer )
  *
diff --git a/include/polarssl/md5.h b/include/polarssl/md5.h
index 2f62ed1d5..ac28a0b41 100644
--- a/include/polarssl/md5.h
+++ b/include/polarssl/md5.h
@@ -113,6 +113,13 @@ void md5_hmac_update( md5_context *ctx,
  */
 void md5_hmac_finish( md5_context *ctx, unsigned char output[16] );
 
+/**
+ * \brief          MD5 HMAC context reset
+ *
+ * \param ctx      HMAC context to be reset
+ */
+void md5_hmac_reset( md5_context *ctx );
+
 /**
  * \brief          Output = HMAC-MD5( hmac key, input buffer )
  *
diff --git a/include/polarssl/sha1.h b/include/polarssl/sha1.h
index ec084500a..060f7203c 100644
--- a/include/polarssl/sha1.h
+++ b/include/polarssl/sha1.h
@@ -111,6 +111,13 @@ void sha1_hmac_update( sha1_context *ctx, const unsigned char *input, int ilen )
  */
 void sha1_hmac_finish( sha1_context *ctx, unsigned char output[20] );
 
+/**
+ * \brief          SHA-1 HMAC context reset
+ *
+ * \param ctx      HMAC context to be reset
+ */
+void sha1_hmac_reset( sha1_context *ctx );
+
 /**
  * \brief          Output = HMAC-SHA-1( hmac key, input buffer )
  *
diff --git a/include/polarssl/sha2.h b/include/polarssl/sha2.h
index 8b65e9f67..d9f3855ea 100644
--- a/include/polarssl/sha2.h
+++ b/include/polarssl/sha2.h
@@ -118,6 +118,13 @@ void sha2_hmac_update( sha2_context *ctx, const unsigned char *input, int ilen )
  */
 void sha2_hmac_finish( sha2_context *ctx, unsigned char output[32] );
 
+/**
+ * \brief          SHA-256 HMAC context reset
+ *
+ * \param ctx      HMAC context to be reset
+ */
+void sha2_hmac_reset( sha2_context *ctx );
+
 /**
  * \brief          Output = HMAC-SHA-256( hmac key, input buffer )
  *
diff --git a/include/polarssl/sha4.h b/include/polarssl/sha4.h
index 3a14c9164..eb35f04e7 100644
--- a/include/polarssl/sha4.h
+++ b/include/polarssl/sha4.h
@@ -126,6 +126,13 @@ void sha4_hmac_update( sha4_context *ctx, const unsigned char *input, int ilen )
  */
 void sha4_hmac_finish( sha4_context *ctx, unsigned char output[64] );
 
+/**
+ * \brief          SHA-512 HMAC context reset
+ *
+ * \param ctx      HMAC context to be reset
+ */
+void sha4_hmac_reset( sha4_context *ctx );
+
 /**
  * \brief          Output = HMAC-SHA-512( hmac key, input buffer )
  *
diff --git a/library/md2.c b/library/md2.c
index 061ebbe34..3a0d1f5aa 100644
--- a/library/md2.c
+++ b/library/md2.c
@@ -260,6 +260,15 @@ void md2_hmac_finish( md2_context *ctx, unsigned char output[16] )
     memset( tmpbuf, 0, sizeof( tmpbuf ) );
 }
 
+/*
+ * MD2 HMAC context reset
+ */
+void md2_hmac_reset( md2_context *ctx )
+{
+    md2_starts( ctx );
+    md2_update( ctx, ctx->ipad, 64 );
+}
+
 /*
  * output = HMAC-MD2( hmac key, input buffer )
  */
diff --git a/library/md4.c b/library/md4.c
index 251e63f16..564a7f9ee 100644
--- a/library/md4.c
+++ b/library/md4.c
@@ -356,6 +356,15 @@ void md4_hmac_finish( md4_context *ctx, unsigned char output[16] )
     memset( tmpbuf, 0, sizeof( tmpbuf ) );
 }
 
+/*
+ * MD4 HMAC context reset
+ */
+void md4_hmac_reset( md4_context *ctx )
+{
+    md4_starts( ctx );
+    md4_update( ctx, ctx->ipad, 64 );
+}
+
 /*
  * output = HMAC-MD4( hmac key, input buffer )
  */
diff --git a/library/md5.c b/library/md5.c
index ca994b9c1..5ab33835b 100644
--- a/library/md5.c
+++ b/library/md5.c
@@ -375,6 +375,15 @@ void md5_hmac_finish( md5_context *ctx, unsigned char output[16] )
     memset( tmpbuf, 0, sizeof( tmpbuf ) );
 }
 
+/*
+ * MD5 HMAC context reset
+ */
+void md5_hmac_reset( md5_context *ctx )
+{
+    md5_starts( ctx );
+    md5_update( ctx, ctx->ipad, 64 );
+}
+
 /*
  * output = HMAC-MD5( hmac key, input buffer )
  */
diff --git a/library/sha1.c b/library/sha1.c
index f811131fc..7f8ec6342 100644
--- a/library/sha1.c
+++ b/library/sha1.c
@@ -410,6 +410,15 @@ void sha1_hmac_finish( sha1_context *ctx, unsigned char output[20] )
     memset( tmpbuf, 0, sizeof( tmpbuf ) );
 }
 
+/*
+ * SHA1 HMAC context reset
+ */
+void sha1_hmac_reset( sha1_context *ctx )
+{
+    sha1_starts( ctx );
+    sha1_update( ctx, ctx->ipad, 64 );
+}
+
 /*
  * output = HMAC-SHA-1( hmac key, input buffer )
  */
diff --git a/library/sha2.c b/library/sha2.c
index 87f02ea58..8f920ce44 100644
--- a/library/sha2.c
+++ b/library/sha2.c
@@ -417,6 +417,15 @@ void sha2_hmac_finish( sha2_context *ctx, unsigned char output[32] )
     memset( tmpbuf, 0, sizeof( tmpbuf ) );
 }
 
+/*
+ * SHA-256 HMAC context reset
+ */
+void sha2_hmac_reset( sha2_context *ctx )
+{
+    sha2_starts( ctx, ctx->is224 );
+    sha2_update( ctx, ctx->ipad, 64 );
+}
+
 /*
  * output = HMAC-SHA-256( hmac key, input buffer )
  */
diff --git a/library/sha4.c b/library/sha4.c
index c21454398..699cca7ae 100644
--- a/library/sha4.c
+++ b/library/sha4.c
@@ -416,6 +416,15 @@ void sha4_hmac_finish( sha4_context *ctx, unsigned char output[64] )
     memset( tmpbuf, 0, sizeof( tmpbuf ) );
 }
 
+/*
+ * SHA-512 HMAC context reset
+ */
+void sha4_hmac_reset( sha4_context *ctx )
+{
+    sha4_starts( ctx, ctx->is384 );
+    sha4_update( ctx, ctx->ipad, 128 );
+}
+
 /*
  * output = HMAC-SHA-512( hmac key, input buffer )
  */