+/**
+ * \file rsa.h
+ *
+ * Based on XySSL: Copyright (C) 2006-2008 Christophe Devine
+ *
+ * Copyright (C) 2009 Paul Bakker <polarssl_maintainer at polarssl dot org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+/* $Cambridge: exim/src/src/pdkim/rsa.h,v 1.2 2009/06/10 07:34:05 tom Exp $ */
+
+#ifndef POLARSSL_RSA_H
+#define POLARSSL_RSA_H
+
+#include "bignum.h"
+
+#define POLARSSL_ERR_RSA_BAD_INPUT_DATA -0x0400
+#define POLARSSL_ERR_RSA_INVALID_PADDING -0x0410
+#define POLARSSL_ERR_RSA_KEY_GEN_FAILED -0x0420
+#define POLARSSL_ERR_RSA_KEY_CHECK_FAILED -0x0430
+#define POLARSSL_ERR_RSA_PUBLIC_FAILED -0x0440
+#define POLARSSL_ERR_RSA_PRIVATE_FAILED -0x0450
+#define POLARSSL_ERR_RSA_VERIFY_FAILED -0x0460
+#define POLARSSL_ERR_RSA_OUTPUT_TO_LARGE -0x0470
+
+#define POLARSSL_ERR_ASN1_OUT_OF_DATA -0x0014
+#define POLARSSL_ERR_ASN1_UNEXPECTED_TAG -0x0016
+#define POLARSSL_ERR_ASN1_INVALID_LENGTH -0x0018
+#define POLARSSL_ERR_ASN1_LENGTH_MISMATCH -0x001A
+#define POLARSSL_ERR_ASN1_INVALID_DATA -0x001C
+
+#define POLARSSL_ERR_X509_FEATURE_UNAVAILABLE -0x0020
+#define POLARSSL_ERR_X509_CERT_INVALID_PEM -0x0040
+#define POLARSSL_ERR_X509_CERT_INVALID_FORMAT -0x0060
+#define POLARSSL_ERR_X509_CERT_INVALID_VERSION -0x0080
+#define POLARSSL_ERR_X509_CERT_INVALID_SERIAL -0x00A0
+#define POLARSSL_ERR_X509_CERT_INVALID_ALG -0x00C0
+#define POLARSSL_ERR_X509_CERT_INVALID_NAME -0x00E0
+#define POLARSSL_ERR_X509_CERT_INVALID_DATE -0x0100
+#define POLARSSL_ERR_X509_CERT_INVALID_PUBKEY -0x0120
+#define POLARSSL_ERR_X509_CERT_INVALID_SIGNATURE -0x0140
+#define POLARSSL_ERR_X509_CERT_INVALID_EXTENSIONS -0x0160
+#define POLARSSL_ERR_X509_CERT_UNKNOWN_VERSION -0x0180
+#define POLARSSL_ERR_X509_CERT_UNKNOWN_SIG_ALG -0x01A0
+#define POLARSSL_ERR_X509_CERT_UNKNOWN_PK_ALG -0x01C0
+#define POLARSSL_ERR_X509_CERT_SIG_MISMATCH -0x01E0
+#define POLARSSL_ERR_X509_CERT_VERIFY_FAILED -0x0200
+#define POLARSSL_ERR_X509_KEY_INVALID_PEM -0x0220
+#define POLARSSL_ERR_X509_KEY_INVALID_VERSION -0x0240
+#define POLARSSL_ERR_X509_KEY_INVALID_FORMAT -0x0260
+#define POLARSSL_ERR_X509_KEY_INVALID_ENC_IV -0x0280
+#define POLARSSL_ERR_X509_KEY_UNKNOWN_ENC_ALG -0x02A0
+#define POLARSSL_ERR_X509_KEY_PASSWORD_REQUIRED -0x02C0
+#define POLARSSL_ERR_X509_KEY_PASSWORD_MISMATCH -0x02E0
+#define POLARSSL_ERR_X509_POINT_ERROR -0x0300
+#define POLARSSL_ERR_X509_VALUE_TO_LENGTH -0x0320
+
+/*
+ * DER constants
+ */
+#define ASN1_BOOLEAN 0x01
+#define ASN1_INTEGER 0x02
+#define ASN1_BIT_STRING 0x03
+#define ASN1_OCTET_STRING 0x04
+#define ASN1_NULL 0x05
+#define ASN1_OID 0x06
+#define ASN1_UTF8_STRING 0x0C
+#define ASN1_SEQUENCE 0x10
+#define ASN1_SET 0x11
+#define ASN1_PRINTABLE_STRING 0x13
+#define ASN1_T61_STRING 0x14
+#define ASN1_IA5_STRING 0x16
+#define ASN1_UTC_TIME 0x17
+#define ASN1_UNIVERSAL_STRING 0x1C
+#define ASN1_BMP_STRING 0x1E
+#define ASN1_PRIMITIVE 0x00
+#define ASN1_CONSTRUCTED 0x20
+#define ASN1_CONTEXT_SPECIFIC 0x80
+
+/*
+ * 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"
+
+#define ASN1_HASH_SHA256 \
+ "\x30\x31\x30\x0d\x06\x09\x60\x86\x48" \
+ "\x01\x65\x03\x04\x02\x01\x05\x00\x04" \
+ "\x20"
+
+/**
+ * \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 POLARSSL_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 POLARSSL_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 POLARSSL_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 POLARSSL_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 POLARSSL_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 POLARSSL_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
+ * \param output_max_len maximum length of the output buffer
+ *
+ * \return 0 if successful, or an POLARSSL_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) otherwise
+ * an error is thrown.
+ */
+int rsa_pkcs1_decrypt( rsa_context *ctx,
+ int mode, int *olen,
+ unsigned char *input,
+ unsigned char *output,
+ int output_max_len);
+
+/**
+ * \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 POLARSSL_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 POLARSSL_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 );
+
+int rsa_parse_public_key( rsa_context *rsa, unsigned char *buf, int buflen );
+
+int rsa_parse_key( rsa_context *rsa, unsigned char *buf, int buflen,
+ unsigned char *pwd, int pwdlen );
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* rsa.h */