diff --git a/include/polarssl/rsa.h b/include/polarssl/rsa.h
new file mode 100644
index 0000000..9a8a5dc
--- /dev/null
+++ b/include/polarssl/rsa.h
@@ -0,0 +1,274 @@
+/**
+ * \file rsa.h
+ */
+#ifndef XYSSL_RSA_H
+#define XYSSL_RSA_H
+
+#include "xyssl/bignum.h"
+
+#define XYSSL_ERR_RSA_BAD_INPUT_DATA                    -0x0400
+#define XYSSL_ERR_RSA_INVALID_PADDING                   -0x0410
+#define XYSSL_ERR_RSA_KEY_GEN_FAILED                    -0x0420
+#define XYSSL_ERR_RSA_KEY_CHECK_FAILED                  -0x0430
+#define XYSSL_ERR_RSA_PUBLIC_FAILED                     -0x0440
+#define XYSSL_ERR_RSA_PRIVATE_FAILED                    -0x0450
+#define XYSSL_ERR_RSA_VERIFY_FAILED                     -0x0460
+
+/*
+ * PKCS#1 constants
+ */
+#define RSA_RAW         0
+#define RSA_MD2         2
+#define RSA_MD4         3
+#define RSA_MD5         4
+#define RSA_SHA1        5
+#define RSA_SHA256      6
+
+#define RSA_PUBLIC      0
+#define RSA_PRIVATE     1
+
+#define RSA_PKCS_V15    0
+#define RSA_PKCS_V21    1
+
+#define RSA_SIGN        1
+#define RSA_CRYPT       2
+
+/*
+ * DigestInfo ::= SEQUENCE {
+ *   digestAlgorithm DigestAlgorithmIdentifier,
+ *   digest Digest }
+ *
+ * DigestAlgorithmIdentifier ::= AlgorithmIdentifier
+ *
+ * Digest ::= OCTET STRING
+ */
+#define ASN1_HASH_MDX                       \
+    "\x30\x20\x30\x0C\x06\x08\x2A\x86\x48"  \
+    "\x86\xF7\x0D\x02\x00\x05\x00\x04\x10"
+
+#define ASN1_HASH_SHA1                      \
+    "\x30\x21\x30\x09\x06\x05\x2B\x0E\x03"  \
+    "\x02\x1A\x05\x00\x04\x14"
+
+/**
+ * \brief          RSA context structure
+ */
+typedef struct
+{
+    int ver;                    /*!<  always 0          */
+    int len;                    /*!<  size(N) in chars  */
+
+    mpi N;                      /*!<  public modulus    */
+    mpi E;                      /*!<  public exponent   */
+
+    mpi D;                      /*!<  private exponent  */
+    mpi P;                      /*!<  1st prime factor  */
+    mpi Q;                      /*!<  2nd prime factor  */
+    mpi DP;                     /*!<  D % (P - 1)       */
+    mpi DQ;                     /*!<  D % (Q - 1)       */
+    mpi QP;                     /*!<  1 / (Q % P)       */
+
+    mpi RN;                     /*!<  cached R^2 mod N  */
+    mpi RP;                     /*!<  cached R^2 mod P  */
+    mpi RQ;                     /*!<  cached R^2 mod Q  */
+
+    int padding;                /*!<  1.5 or OAEP/PSS   */
+    int hash_id;                /*!<  hash identifier   */
+    int (*f_rng)(void *);       /*!<  RNG function      */
+    void *p_rng;                /*!<  RNG parameter     */
+}
+rsa_context;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * \brief          Initialize an RSA context
+ *
+ * \param ctx      RSA context to be initialized
+ * \param padding  RSA_PKCS_V15 or RSA_PKCS_V21
+ * \param hash_id  RSA_PKCS_V21 hash identifier
+ * \param f_rng    RNG function
+ * \param p_rng    RNG parameter
+ *
+ * \note           The hash_id parameter is actually ignored
+ *                 when using RSA_PKCS_V15 padding.
+ *
+ * \note           Currently (xyssl-0.8), RSA_PKCS_V21 padding
+ *                 is not supported.
+ */
+void rsa_init( rsa_context *ctx,
+               int padding,
+               int hash_id,
+               int (*f_rng)(void *),
+               void *p_rng );
+
+/**
+ * \brief          Generate an RSA keypair
+ *
+ * \param ctx      RSA context that will hold the key
+ * \param nbits    size of the public key in bits
+ * \param exponent public exponent (e.g., 65537)
+ *
+ * \note           rsa_init() must be called beforehand to setup
+ *                 the RSA context (especially f_rng and p_rng).
+ *
+ * \return         0 if successful, or an XYSSL_ERR_RSA_XXX error code
+ */
+int rsa_gen_key( rsa_context *ctx, int nbits, int exponent );
+
+/**
+ * \brief          Check a public RSA key
+ *
+ * \param ctx      RSA context to be checked
+ *
+ * \return         0 if successful, or an XYSSL_ERR_RSA_XXX error code
+ */
+int rsa_check_pubkey( rsa_context *ctx );
+
+/**
+ * \brief          Check a private RSA key
+ *
+ * \param ctx      RSA context to be checked
+ *
+ * \return         0 if successful, or an XYSSL_ERR_RSA_XXX error code
+ */
+int rsa_check_privkey( rsa_context *ctx );
+
+/**
+ * \brief          Do an RSA public key operation
+ *
+ * \param ctx      RSA context
+ * \param input    input buffer
+ * \param output   output buffer
+ *
+ * \return         0 if successful, or an XYSSL_ERR_RSA_XXX error code
+ *
+ * \note           This function does NOT take care of message
+ *                 padding. Also, be sure to set input[0] = 0.
+ *
+ * \note           The input and output buffers must be large
+ *                 enough (eg. 128 bytes if RSA-1024 is used).
+ */
+int rsa_public( rsa_context *ctx,
+                unsigned char *input,
+                unsigned char *output );
+
+/**
+ * \brief          Do an RSA private key operation
+ *
+ * \param ctx      RSA context
+ * \param input    input buffer
+ * \param output   output buffer
+ *
+ * \return         0 if successful, or an XYSSL_ERR_RSA_XXX error code
+ *
+ * \note           The input and output buffers must be large
+ *                 enough (eg. 128 bytes if RSA-1024 is used).
+ */
+int rsa_private( rsa_context *ctx,
+                 unsigned char *input,
+                 unsigned char *output );
+
+/**
+ * \brief          Add the message padding, then do an RSA operation
+ *
+ * \param ctx      RSA context
+ * \param mode     RSA_PUBLIC or RSA_PRIVATE
+ * \param ilen     contains the the plaintext length
+ * \param input    buffer holding the data to be encrypted
+ * \param output   buffer that will hold the ciphertext
+ *
+ * \return         0 if successful, or an XYSSL_ERR_RSA_XXX error code
+ *
+ * \note           The output buffer must be as large as the size
+ *                 of ctx->N (eg. 128 bytes if RSA-1024 is used).
+ */
+int rsa_pkcs1_encrypt( rsa_context *ctx,
+                       int mode, int  ilen,
+                       unsigned char *input,
+                       unsigned char *output );
+
+/**
+ * \brief          Do an RSA operation, then remove the message padding
+ *
+ * \param ctx      RSA context
+ * \param mode     RSA_PUBLIC or RSA_PRIVATE
+ * \param input    buffer holding the encrypted data
+ * \param output   buffer that will hold the plaintext
+ * \param olen     will contain the plaintext length
+ *
+ * \return         0 if successful, or an XYSSL_ERR_RSA_XXX error code
+ *
+ * \note           The output buffer must be as large as the size
+ *                 of ctx->N (eg. 128 bytes if RSA-1024 is used).
+ */
+int rsa_pkcs1_decrypt( rsa_context *ctx,
+                       int mode, int *olen,
+                       unsigned char *input,
+                       unsigned char *output );
+
+/**
+ * \brief          Do a private RSA to sign a message digest
+ *
+ * \param ctx      RSA context
+ * \param mode     RSA_PUBLIC or RSA_PRIVATE
+ * \param hash_id  RSA_RAW, RSA_MD{2,4,5} or RSA_SHA{1,256}
+ * \param hashlen  message digest length (for RSA_RAW only)
+ * \param hash     buffer holding the message digest
+ * \param sig      buffer that will hold the ciphertext
+ *
+ * \return         0 if the signing operation was successful,
+ *                 or an XYSSL_ERR_RSA_XXX error code
+ *
+ * \note           The "sig" buffer must be as large as the size
+ *                 of ctx->N (eg. 128 bytes if RSA-1024 is used).
+ */
+int rsa_pkcs1_sign( rsa_context *ctx,
+                    int mode,
+                    int hash_id,
+                    int hashlen,
+                    unsigned char *hash,
+                    unsigned char *sig );
+
+/**
+ * \brief          Do a public RSA and check the message digest
+ *
+ * \param ctx      points to an RSA public key
+ * \param mode     RSA_PUBLIC or RSA_PRIVATE
+ * \param hash_id  RSA_RAW, RSA_MD{2,4,5} or RSA_SHA{1,256}
+ * \param hashlen  message digest length (for RSA_RAW only)
+ * \param hash     buffer holding the message digest
+ * \param sig      buffer holding the ciphertext
+ *
+ * \return         0 if the verify operation was successful,
+ *                 or an XYSSL_ERR_RSA_XXX error code
+ *
+ * \note           The "sig" buffer must be as large as the size
+ *                 of ctx->N (eg. 128 bytes if RSA-1024 is used).
+ */
+int rsa_pkcs1_verify( rsa_context *ctx,
+                      int mode,
+                      int hash_id,
+                      int hashlen,
+                      unsigned char *hash,
+                      unsigned char *sig );
+
+/**
+ * \brief          Free the components of an RSA key
+ */
+void rsa_free( rsa_context *ctx );
+
+/**
+ * \brief          Checkup routine
+ *
+ * \return         0 if successful, or 1 if the test failed
+ */
+int rsa_self_test( int verbose );
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* rsa.h */