/** * \file rsa.h */ #ifndef POLARSSL_RSA_H #define POLARSSL_RSA_H #include "polarssl/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 /* * 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 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 * * \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_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 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 ); /** * \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 */