Initial revision
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+/*
+
+rsa.c
+
+Author: Tatu Ylonen <ylo@cs.hut.fi>
+
+Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, 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 <aba@atlax.ex.ac.uk>, 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;
+}