/* rsa.c Author: Tatu Ylonen Copyright (c) 1995 Tatu Ylonen , Espoo, Finland All rights reserved Created: Fri Mar 3 22:07:06 1995 ylo Description of the RSA algorithm can be found e.g. from the following sources: Bruce Schneier: Applied Cryptography. John Wiley & Sons, 1994. Jennifer Seberry and Josed Pieprzyk: Cryptography: An Introduction to Computer Security. Prentice-Hall, 1989. Man Young Rhee: Cryptography and Secure Data Communications. McGraw-Hill, 1994. R. Rivest, A. Shamir, and L. M. Adleman: Cryptographic Communications System and Method. US Patent 4,405,829, 1983. Hans Riesel: Prime Numbers and Computer Methods for Factorization. Birkhauser, 1994. The RSA Frequently Asked Questions document by RSA Data Security, Inc., 1995. RSA in 3 lines of perl by Adam Back , 1995, as included below: gone - had to be deleted - what a pity */ #include "includes.h" RCSID("\$Id: rsa.c,v 1.1 1999/10/27 03:42:44 damien Exp \$"); #include "rsa.h" #include "ssh.h" #include "xmalloc.h" int rsa_verbose = 1; int rsa_alive() { RSA *key; key = RSA_generate_key(32, 3, NULL, NULL); if (key == NULL) return (0); RSA_free(key); return (1); } /* Generates RSA public and private keys. This initializes the data structures; they should be freed with rsa_clear_private_key and rsa_clear_public_key. */ void rsa_generate_key(RSA *prv, RSA *pub, unsigned int bits) { RSA *key; if (rsa_verbose) { printf("Generating RSA keys: "); fflush(stdout); } key = RSA_generate_key(bits, 35, NULL, NULL); assert(key != NULL); /* Copy public key parameters */ pub->n = BN_new(); BN_copy(pub->n, key->n); pub->e = BN_new(); BN_copy(pub->e, key->e); /* Copy private key parameters */ prv->n = BN_new(); BN_copy(prv->n, key->n); prv->e = BN_new(); BN_copy(prv->e, key->e); prv->d = BN_new(); BN_copy(prv->d, key->d); prv->p = BN_new(); BN_copy(prv->p, key->p); prv->q = BN_new(); BN_copy(prv->q, key->q); prv->dmp1 = BN_new(); BN_copy(prv->dmp1, key->dmp1); prv->dmq1 = BN_new(); BN_copy(prv->dmq1, key->dmq1); prv->iqmp = BN_new(); BN_copy(prv->iqmp, key->iqmp); RSA_free(key); if (rsa_verbose) printf("Key generation complete.\n"); } void rsa_public_encrypt(BIGNUM *out, BIGNUM *in, RSA* key) { char *inbuf, *outbuf; int len; if (BN_num_bits(key->e) < 2 || !BN_is_odd(key->e)) fatal("rsa_public_encrypt() exponent too small or not odd"); len = BN_num_bytes(key->n); outbuf = xmalloc(len); len = BN_num_bytes(in); inbuf = xmalloc(len); BN_bn2bin(in, inbuf); if ((len = RSA_public_encrypt(len, inbuf, outbuf, key, RSA_PKCS1_PADDING)) <= 0) fatal("rsa_public_encrypt() failed"); BN_bin2bn(outbuf, len, out); xfree(outbuf); xfree(inbuf); } void rsa_private_decrypt(BIGNUM *out, BIGNUM *in, RSA *key) { char *inbuf, *outbuf; int len; len = BN_num_bytes(key->n); outbuf = xmalloc(len); len = BN_num_bytes(in); inbuf = xmalloc(len); BN_bn2bin(in, inbuf); if ((len = RSA_private_decrypt(len, inbuf, outbuf, key, RSA_SSLV23_PADDING)) <= 0) fatal("rsa_private_decrypt() failed"); BN_bin2bn(outbuf, len, out); xfree(outbuf); xfree(inbuf); } /* Set whether to output verbose messages during key generation. */ void rsa_set_verbose(int verbose) { rsa_verbose = verbose; }