-/*
+/*
* rsa.c RSA Public and Private key generation functions,
* RSA encrypt and decrypt functions.
*
- * Author: Pekka Riikonen <priikone@poseidon.pspt.fi>
+ * Author: Pekka Riikonen <priikone@silcnet.org>
*
- * Copyright (C) 1997 - 2001 Pekka Riikonen
+ * Copyright (C) 1997 - 2003 Pekka Riikonen
*
* 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
* Decryption:
* m = c ^ d mod n
*
- * The SSH's (Secure Shell), PGP's (Pretty Good Privacy) and RSAREF
- * Toolkit were used as reference when coding this implementation. They
+ * Supports CRT (Chinese Remainder Theorem) for private key operations.
+ *
+ * The SSH's (Secure Shell), PGP's (Pretty Good Privacy) and RSAREF
+ * Toolkit were used as reference when coding this implementation. They
* all were a big help for me.
*
- * I also suggest reading Bruce Schneier's; Applied Cryptography, Second
- * Edition, John Wiley & Sons, Inc. 1996. This book deals about RSA and
+ * I also suggest reading Bruce Schneier's; Applied Cryptography, Second
+ * Edition, John Wiley & Sons, Inc. 1996. This book deals about RSA and
* everything else too about cryptography.
*
*/
o Sat Mar 16 18:27:19 EET 2002 Pekka
- Use the SilcRng sent as argument to SILC_PKCS_API_INIT in prime
+ Use the SilcRng sent as argument to SILC_PKCS_API_INIT in prime
generation.
o Sat Sep 26 19:59:48 EEST 2002 Pekka
SilcMPInt p, q;
bool found = FALSE;
+ if (keylen < 768 || keylen > 16384)
+ return FALSE;
+
printf("Generating RSA Public and Private keys, might take a while...\n");
silc_mp_init(&p);
while (!found) {
printf("Finding p: ");
silc_math_gen_prime(&p, prime_bits, TRUE, rng);
-
+
printf("\nFinding q: ");
silc_math_gen_prime(&q, prime_bits, TRUE, rng);
silc_mp_uninit(&p);
silc_mp_uninit(&q);
-
+
printf("\nKeys generated successfully.\n");
return TRUE;
SILC_PKCS_API_GET_PRIVATE_KEY(rsa)
{
RsaKey *key = (RsaKey *)context;
- unsigned char *e, *n, *d, *ret;
- SilcUInt32 e_len, n_len, d_len;
- unsigned char tmp[4];
+ SilcBuffer buf;
+ unsigned char *e, *n, *d, *ret, *dp = NULL, *dq = NULL;
+ unsigned char *pq = NULL, *qp = NULL, *p = NULL, *q = NULL;
+ SilcUInt32 e_len, n_len, d_len, dp_len, dq_len, pq_len, qp_len, p_len, q_len;
+ SilcUInt32 len = 0;
e = silc_mp_mp2bin(&key->e, 0, &e_len);
n = silc_mp_mp2bin(&key->n, (key->bits + 7) / 8, &n_len);
d = silc_mp_mp2bin(&key->d, 0, &d_len);
+ if (key->crt) {
+ dp = silc_mp_mp2bin(&key->dP, 0, &dp_len);
+ dq = silc_mp_mp2bin(&key->dQ, 0, &dq_len);
+ pq = silc_mp_mp2bin(&key->pQ, 0, &pq_len);
+ qp = silc_mp_mp2bin(&key->qP, 0, &qp_len);
+ p = silc_mp_mp2bin(&key->p, 0, &p_len);
+ q = silc_mp_mp2bin(&key->q, 0, &q_len);
+ len = dp_len + 4 + dq_len + 4 + pq_len + 4 + qp_len + 4 + p_len + 4 +
+ q_len + 4;
+ }
- *ret_len = e_len + 4 + n_len + 4 + d_len + 4;
- ret = silc_calloc(*ret_len, sizeof(unsigned char));
-
- /* Put the length of the e. */
- SILC_PUT32_MSB(e_len, tmp);
- memcpy(ret, tmp, 4);
-
- /* Put the e. */
- memcpy(ret + 4, e, e_len);
-
- /* Put the length of the n. */
- SILC_PUT32_MSB(n_len, tmp);
- memcpy(ret + 4 + e_len, tmp, 4);
-
- /* Put the n. */
- memcpy(ret + 4 + e_len + 4, n, n_len);
-
- /* Put the length of the d. */
- SILC_PUT32_MSB(d_len, tmp);
- memcpy(ret + 4 + e_len + 4 + n_len, tmp, 4);
-
- /* Put the n. */
- memcpy(ret + 4 + e_len + 4 + n_len + 4, d, d_len);
+ buf = silc_buffer_alloc_size(e_len + 4 + n_len + 4 + d_len + 4 + len);
+ len = silc_buffer_format(buf,
+ SILC_STR_UI_INT(e_len),
+ SILC_STR_UI_XNSTRING(e, e_len),
+ SILC_STR_UI_INT(n_len),
+ SILC_STR_UI_XNSTRING(n, n_len),
+ SILC_STR_UI_INT(d_len),
+ SILC_STR_UI_XNSTRING(d, d_len),
+ SILC_STR_END);
+
+ if (key->crt) {
+ silc_buffer_pull(buf, len);
+ silc_buffer_format(buf,
+ SILC_STR_UI_INT(dp_len),
+ SILC_STR_UI_XNSTRING(dp, dp_len),
+ SILC_STR_UI_INT(dq_len),
+ SILC_STR_UI_XNSTRING(dq, dq_len),
+ SILC_STR_UI_INT(pq_len),
+ SILC_STR_UI_XNSTRING(pq, pq_len),
+ SILC_STR_UI_INT(qp_len),
+ SILC_STR_UI_XNSTRING(qp, qp_len),
+ SILC_STR_UI_INT(p_len),
+ SILC_STR_UI_XNSTRING(p, p_len),
+ SILC_STR_UI_INT(q_len),
+ SILC_STR_UI_XNSTRING(q, q_len),
+ SILC_STR_END);
+ silc_buffer_push(buf, len);
+
+ memset(dp, 0, dp_len);
+ memset(dq, 0, dq_len);
+ memset(pq, 0, pq_len);
+ memset(qp, 0, qp_len);
+ memset(p, 0, p_len);
+ memset(q, 0, q_len);
+ silc_free(dp);
+ silc_free(dq);
+ silc_free(pq);
+ silc_free(qp);
+ silc_free(p);
+ silc_free(q);
+ }
- memset(e, 0, e_len);
- memset(n, 0, n_len);
memset(d, 0, d_len);
silc_free(e);
silc_free(n);
silc_free(d);
+ ret = silc_buffer_steal(buf, ret_len);
+ silc_buffer_free(buf);
return ret;
}
SILC_PKCS_API_SET_PRIVATE_KEY(rsa)
{
RsaKey *key = (RsaKey *)context;
- unsigned char tmp[4];
- SilcUInt32 e_len, n_len, d_len;
+ SilcBufferStruct k;
+ unsigned char *tmp;
+ SilcUInt32 len;
if (key->prv_set) {
silc_mp_uninit(&key->d);
if (key_len < 4)
return FALSE;
+ silc_buffer_set(&k, key_data, key_len);
+
silc_mp_init(&key->e);
silc_mp_init(&key->n);
silc_mp_init(&key->d);
+ key->prv_set = TRUE;
+ key->pub_set = TRUE;
- memcpy(tmp, key_data, 4);
- SILC_GET32_MSB(e_len, tmp);
- if (e_len + 4 > key_len) {
- silc_mp_uninit(&key->e);
- silc_mp_uninit(&key->n);
- silc_mp_uninit(&key->d);
- return FALSE;
- }
-
- silc_mp_bin2mp(key_data + 4, e_len, &key->e);
-
- if (key_len < e_len + 4 + 4) {
- silc_mp_uninit(&key->e);
- silc_mp_uninit(&key->n);
- silc_mp_uninit(&key->d);
- return FALSE;
- }
-
- memcpy(tmp, key_data + 4 + e_len, 4);
- SILC_GET32_MSB(n_len, tmp);
- if (e_len + 4 + n_len + 4 > key_len) {
- silc_mp_uninit(&key->e);
- silc_mp_uninit(&key->n);
- silc_mp_uninit(&key->d);
- return FALSE;
- }
-
- silc_mp_bin2mp(key_data + 4 + e_len + 4, n_len, &key->n);
-
- if (key_len < e_len + 4 + n_len + 4 + 4) {
- silc_mp_uninit(&key->e);
- silc_mp_uninit(&key->n);
- silc_mp_uninit(&key->d);
- return FALSE;
- }
-
- memcpy(tmp, key_data + 4 + e_len + 4 + n_len, 4);
- SILC_GET32_MSB(d_len, tmp);
- if (e_len + 4 + n_len + 4 + d_len + 4 > key_len) {
- silc_mp_uninit(&key->e);
- silc_mp_uninit(&key->n);
- silc_mp_uninit(&key->d);
- return FALSE;
+ /* Get e */
+ if (silc_buffer_unformat(&k,
+ SILC_STR_UI_INT(&len),
+ SILC_STR_END) < 0)
+ goto err;
+ silc_buffer_pull(&k, 4);
+ if (silc_buffer_unformat(&k,
+ SILC_STR_UI_XNSTRING(&tmp, len),
+ SILC_STR_END) < 0)
+ goto err;
+ silc_mp_bin2mp(tmp, len, &key->e);
+ silc_buffer_pull(&k, len);
+
+ /* Get n */
+ if (silc_buffer_unformat(&k,
+ SILC_STR_UI_INT(&len),
+ SILC_STR_END) < 0)
+ goto err;
+ silc_buffer_pull(&k, 4);
+ if (silc_buffer_unformat(&k,
+ SILC_STR_UI_XNSTRING(&tmp, len),
+ SILC_STR_END) < 0)
+ goto err;
+ silc_mp_bin2mp(tmp, len, &key->n);
+ silc_buffer_pull(&k, len);
+
+ /* Get d */
+ if (silc_buffer_unformat(&k,
+ SILC_STR_UI_INT(&len),
+ SILC_STR_END) < 0)
+ goto err;
+ silc_buffer_pull(&k, 4);
+ if (silc_buffer_unformat(&k,
+ SILC_STR_UI_XNSTRING(&tmp, len),
+ SILC_STR_END) < 0)
+ goto err;
+ silc_mp_bin2mp(tmp, len, &key->d);
+ silc_buffer_pull(&k, len);
+
+ /* Get optimized d for CRT, if present. */
+ if (k.len > 4) {
+ key->crt = TRUE;
+ silc_mp_init(&key->dP);
+ silc_mp_init(&key->dQ);
+ silc_mp_init(&key->pQ);
+ silc_mp_init(&key->qP);
+ silc_mp_init(&key->p);
+ silc_mp_init(&key->q);
+
+ /* Get dP */
+ if (silc_buffer_unformat(&k,
+ SILC_STR_UI_INT(&len),
+ SILC_STR_END) < 0)
+ goto err;
+ silc_buffer_pull(&k, 4);
+ if (silc_buffer_unformat(&k,
+ SILC_STR_UI_XNSTRING(&tmp, len),
+ SILC_STR_END) < 0)
+ goto err;
+ silc_mp_bin2mp(tmp, len, &key->dP);
+ silc_buffer_pull(&k, len);
+
+ /* Get dQ */
+ if (silc_buffer_unformat(&k,
+ SILC_STR_UI_INT(&len),
+ SILC_STR_END) < 0)
+ goto err;
+ silc_buffer_pull(&k, 4);
+ if (silc_buffer_unformat(&k,
+ SILC_STR_UI_XNSTRING(&tmp, len),
+ SILC_STR_END) < 0)
+ goto err;
+ silc_mp_bin2mp(tmp, len, &key->dQ);
+ silc_buffer_pull(&k, len);
+
+ /* Get pQ */
+ if (silc_buffer_unformat(&k,
+ SILC_STR_UI_INT(&len),
+ SILC_STR_END) < 0)
+ goto err;
+ silc_buffer_pull(&k, 4);
+ if (silc_buffer_unformat(&k,
+ SILC_STR_UI_XNSTRING(&tmp, len),
+ SILC_STR_END) < 0)
+ goto err;
+ silc_mp_bin2mp(tmp, len, &key->pQ);
+ silc_buffer_pull(&k, len);
+
+ /* Get qP */
+ if (silc_buffer_unformat(&k,
+ SILC_STR_UI_INT(&len),
+ SILC_STR_END) < 0)
+ goto err;
+ silc_buffer_pull(&k, 4);
+ if (silc_buffer_unformat(&k,
+ SILC_STR_UI_XNSTRING(&tmp, len),
+ SILC_STR_END) < 0)
+ goto err;
+ silc_mp_bin2mp(tmp, len, &key->qP);
+ silc_buffer_pull(&k, len);
+
+ /* Get p */
+ if (silc_buffer_unformat(&k,
+ SILC_STR_UI_INT(&len),
+ SILC_STR_END) < 0)
+ goto err;
+ silc_buffer_pull(&k, 4);
+ if (silc_buffer_unformat(&k,
+ SILC_STR_UI_XNSTRING(&tmp, len),
+ SILC_STR_END) < 0)
+ goto err;
+ silc_mp_bin2mp(tmp, len, &key->p);
+ silc_buffer_pull(&k, len);
+
+ /* Get q */
+ if (silc_buffer_unformat(&k,
+ SILC_STR_UI_INT(&len),
+ SILC_STR_END) < 0)
+ goto err;
+ silc_buffer_pull(&k, 4);
+ if (silc_buffer_unformat(&k,
+ SILC_STR_UI_XNSTRING(&tmp, len),
+ SILC_STR_END) < 0)
+ goto err;
+ silc_mp_bin2mp(tmp, len, &key->q);
+ silc_buffer_pull(&k, len);
}
- silc_mp_bin2mp(key_data + 4 + e_len + 4 + n_len + 4, d_len, &key->d);
-
key->bits = silc_mp_sizeinbase(&key->n, 2);
- key->prv_set = TRUE;
- key->pub_set = TRUE;
-
return key->bits;
+
+ err:
+ rsa_clear_keys(key);
+ return FALSE;
}
SILC_PKCS_API_CONTEXT_LEN(rsa)
return sizeof(RsaKey);
}
+/* Raw RSA routines */
+
SILC_PKCS_API_ENCRYPT(rsa)
{
RsaKey *key = (RsaKey *)context;
silc_mp_bin2mp(src, src_len, &mp_tmp);
/* Encrypt */
- rsa_en_de_crypt(&mp_dst, &mp_tmp, &key->e, &key->n);
-
+ rsa_public_operation(key, &mp_tmp, &mp_dst);
+
tmplen = (key->bits + 7) / 8;
/* Format the MP int back into data */
silc_mp_bin2mp(src, src_len, &mp_tmp);
/* Decrypt */
- rsa_en_de_crypt(&mp_dst, &mp_tmp, &key->d, &key->n);
+ rsa_private_operation(key, &mp_tmp, &mp_dst);
tmplen = (key->bits + 7) / 8;
silc_mp_bin2mp(src, src_len, &mp_tmp);
/* Sign */
- rsa_en_de_crypt(&mp_dst, &mp_tmp, &key->d, &key->n);
+ rsa_private_operation(key, &mp_tmp, &mp_dst);
tmplen = (key->bits + 7) / 8;
silc_mp_bin2mp(signature, signature_len, &mp_tmp2);
/* Verify */
- rsa_en_de_crypt(&mp_dst, &mp_tmp2, &key->e, &key->n);
+ rsa_public_operation(key, &mp_tmp2, &mp_dst);
/* Format the data into MP int */
silc_mp_bin2mp(data, data_len, &mp_tmp);
return ret;
}
+
+/* PKCS#1 RSA routines */
+
+SILC_PKCS_API_ENCRYPT(pkcs1)
+{
+ RsaKey *key = (RsaKey *)context;
+ SilcMPInt mp_tmp;
+ SilcMPInt mp_dst;
+ unsigned char padded[2048 + 1];
+ SilcUInt32 len = (key->bits + 7) / 8;
+
+ if (sizeof(padded) < len)
+ return FALSE;
+
+ /* Pad data */
+ if (!silc_pkcs1_encode(SILC_PKCS1_BT_PUB, src, src_len,
+ padded, len, NULL))
+ return FALSE;
+
+ silc_mp_init(&mp_tmp);
+ silc_mp_init(&mp_dst);
+
+ /* Data to MP */
+ silc_mp_bin2mp(padded, len, &mp_tmp);
+
+ /* Encrypt */
+ rsa_public_operation(key, &mp_tmp, &mp_dst);
+
+ /* MP to data */
+ silc_mp_mp2bin_noalloc(&mp_dst, dst, len);
+ *dst_len = len;
+
+ memset(padded, 0, sizeof(padded));
+ silc_mp_uninit(&mp_tmp);
+ silc_mp_uninit(&mp_dst);
+
+ return TRUE;
+}
+
+SILC_PKCS_API_DECRYPT(pkcs1)
+{
+ RsaKey *key = (RsaKey *)context;
+ SilcMPInt mp_tmp;
+ SilcMPInt mp_dst;
+ unsigned char *padded, unpadded[2048 + 1];
+ SilcUInt32 padded_len;
+
+ silc_mp_init(&mp_tmp);
+ silc_mp_init(&mp_dst);
+
+ /* Data to MP */
+ silc_mp_bin2mp(src, src_len, &mp_tmp);
+
+ /* Decrypt */
+ rsa_private_operation(key, &mp_tmp, &mp_dst);
+
+ /* MP to data */
+ padded = silc_mp_mp2bin(&mp_dst, (key->bits + 7) / 8, &padded_len);
+
+ /* Unpad data */
+ if (!silc_pkcs1_decode(SILC_PKCS1_BT_PUB, padded, padded_len,
+ unpadded, sizeof(unpadded), dst_len)) {
+ memset(padded, 0, padded_len);
+ silc_free(padded);
+ silc_mp_uninit(&mp_tmp);
+ silc_mp_uninit(&mp_dst);
+ return FALSE;
+ }
+
+ /* Copy to destination */
+ memcpy(dst, unpadded, *dst_len);
+
+ memset(padded, 0, padded_len);
+ memset(unpadded, 0, sizeof(unpadded));
+ silc_free(padded);
+ silc_mp_uninit(&mp_tmp);
+ silc_mp_uninit(&mp_dst);
+
+ return TRUE;
+}
+
+SILC_PKCS_API_SIGN(pkcs1)
+{
+ RsaKey *key = (RsaKey *)context;
+ SilcMPInt mp_tmp;
+ SilcMPInt mp_dst;
+ unsigned char padded[2048 + 1];
+ SilcUInt32 len = (key->bits + 7) / 8;
+
+ if (sizeof(padded) < len)
+ return FALSE;
+
+ /* Pad data */
+ if (!silc_pkcs1_encode(SILC_PKCS1_BT_PRV1, src, src_len,
+ padded, len, NULL))
+ return FALSE;
+
+ silc_mp_init(&mp_tmp);
+ silc_mp_init(&mp_dst);
+
+ /* Data to MP */
+ silc_mp_bin2mp(padded, len, &mp_tmp);
+
+ /* Sign */
+ rsa_private_operation(key, &mp_tmp, &mp_dst);
+
+ /* MP to data */
+ silc_mp_mp2bin_noalloc(&mp_dst, dst, len);
+ *dst_len = len;
+
+ memset(padded, 0, sizeof(padded));
+ silc_mp_uninit(&mp_tmp);
+ silc_mp_uninit(&mp_dst);
+
+ return TRUE;
+}
+
+SILC_PKCS_API_VERIFY(pkcs1)
+{
+ RsaKey *key = (RsaKey *)context;
+ int ret = TRUE;
+ SilcMPInt mp_tmp2;
+ SilcMPInt mp_dst;
+ unsigned char *verify, unpadded[2048 + 1];
+ SilcUInt32 verify_len, len = (key->bits + 7) / 8;
+
+ silc_mp_init(&mp_tmp2);
+ silc_mp_init(&mp_dst);
+
+ /* Format the signature into MP int */
+ silc_mp_bin2mp(signature, signature_len, &mp_tmp2);
+
+ /* Verify */
+ rsa_public_operation(key, &mp_tmp2, &mp_dst);
+
+ /* MP to data */
+ verify = silc_mp_mp2bin(&mp_dst, len, &verify_len);
+
+ /* Unpad data */
+ if (!silc_pkcs1_decode(SILC_PKCS1_BT_PRV1, verify, verify_len,
+ unpadded, sizeof(unpadded), &len)) {
+ memset(verify, 0, verify_len);
+ silc_free(verify);
+ silc_mp_uninit(&mp_tmp2);
+ silc_mp_uninit(&mp_dst);
+ return FALSE;
+ }
+
+ /* Compare */
+ if (memcmp(data, unpadded, len))
+ ret = FALSE;
+
+ memset(verify, 0, verify_len);
+ memset(unpadded, 0, sizeof(unpadded));
+ silc_free(verify);
+ silc_mp_uninit(&mp_tmp2);
+ silc_mp_uninit(&mp_dst);
+
+ return ret;
+}
+
/* Generates RSA public and private keys. Primes p and q that are used
to compute the modulus n has to be generated before calling this. They
are then sent as argument for the function. */
-void rsa_generate_keys(RsaKey *key, SilcUInt32 bits,
+bool rsa_generate_keys(RsaKey *key, SilcUInt32 bits,
SilcMPInt *p, SilcMPInt *q)
{
SilcMPInt phi, hlp;
SilcMPInt div, lcm;
SilcMPInt pm1, qm1;
-
+
/* Initialize variables */
silc_mp_init(&key->n);
silc_mp_init(&key->e);
silc_mp_init(&key->d);
+ silc_mp_init(&key->dP);
+ silc_mp_init(&key->dQ);
+ silc_mp_init(&key->pQ);
+ silc_mp_init(&key->qP);
silc_mp_init(&phi);
silc_mp_init(&hlp);
silc_mp_init(&div);
/* Compute modulus, n = p * q */
silc_mp_mul(&key->n, p, q);
-
+
/* phi = (p - 1) * (q - 1) */
silc_mp_sub_ui(&pm1, p, 1);
silc_mp_sub_ui(&qm1, q, 1);
silc_mp_mul(&phi, &pm1, &qm1);
-
+
/* Set e, the public exponent. We try to use same public exponent
- for all keys. Also, to make encryption faster we use small
+ for all keys. Also, to make encryption faster we use small
number. */
silc_mp_set_ui(&key->e, 65533);
retry_e:
/* See if e is relatively prime to phi. gcd == greates common divisor,
if gcd equals 1 they are relatively prime. */
silc_mp_gcd(&hlp, &key->e, &phi);
- if((silc_mp_cmp_ui(&hlp, 1)) > 0) {
+ if ((silc_mp_cmp_ui(&hlp, 1)) > 0) {
silc_mp_add_ui(&key->e, &key->e, 2);
goto retry_e;
}
-
+
/* Find d, the private exponent, e ^ -1 mod lcm(phi). */
silc_mp_gcd(&div, &pm1, &qm1);
silc_mp_div(&lcm, &phi, &div);
silc_mp_modinv(&key->d, &key->e, &lcm);
-
+
+ /* Optimize d with CRT. We precompute as much as possible. */
+ silc_mp_mod(&key->dP, &key->d, &pm1);
+ silc_mp_mod(&key->dQ, &key->d, &qm1);
+ silc_mp_modinv(&key->pQ, p, q);
+ silc_mp_mul(&key->pQ, p, &key->pQ);
+ silc_mp_mod(&key->pQ, &key->pQ, &key->n);
+ silc_mp_modinv(&key->qP, q, p);
+ silc_mp_mul(&key->qP, q, &key->qP);
+ silc_mp_mod(&key->qP, &key->qP, &key->n);
+ silc_mp_set(&key->p, p);
+ silc_mp_set(&key->q, q);
+ key->crt = TRUE;
+
silc_mp_uninit(&phi);
silc_mp_uninit(&hlp);
silc_mp_uninit(&div);
silc_mp_uninit(&lcm);
silc_mp_uninit(&pm1);
silc_mp_uninit(&qm1);
+
+ return TRUE;
}
/* Clears whole key structure. */
-void rsa_clear_keys(RsaKey *key)
+bool rsa_clear_keys(RsaKey *key)
{
key->bits = 0;
if (key->pub_set) {
}
if (key->prv_set)
silc_mp_uninit(&key->d);
+ if (key->prv_set && key->crt) {
+ silc_mp_uninit(&key->dP);
+ silc_mp_uninit(&key->dQ);
+ silc_mp_uninit(&key->pQ);
+ silc_mp_uninit(&key->qP);
+ silc_mp_uninit(&key->p);
+ silc_mp_uninit(&key->q);
+ }
+ return TRUE;
}
-/* RSA encrypt/decrypt function. cm = ciphertext or plaintext,
- mc = plaintext or ciphertext, expo = public or private exponent,
- and modu = modulus.
+/* RSA public key operation */
- Encrypt: c = m ^ e mod n,
- Decrypt: m = c ^ d mod n
-*/
+bool rsa_public_operation(RsaKey *key, SilcMPInt *src, SilcMPInt *dst)
+{
+ /* dst = src ^ e mod n */
+ silc_mp_pow_mod(dst, src, &key->e, &key->n);
+ return TRUE;
+}
+
+/* RSA private key operation */
-void rsa_en_de_crypt(SilcMPInt *cm, SilcMPInt *mc,
- SilcMPInt *expo, SilcMPInt *modu)
+bool rsa_private_operation(RsaKey *key, SilcMPInt *src, SilcMPInt *dst)
{
- silc_mp_pow_mod(cm, mc, expo, modu);
+ if (!key->crt) {
+ /* dst = src ^ d mod n */
+ silc_mp_pow_mod(dst, src, &key->d, &key->n);
+ } else {
+ /* CRT */
+ SilcMPInt tmp;
+
+ silc_mp_init(&tmp);
+
+ /* dst = ((src ^ dP mod p) * qP) + ((src ^ dQ mod q) * pQ) mod n */
+ silc_mp_pow_mod(dst, src, &key->dP, &key->p);
+ silc_mp_mul(dst, dst, &key->qP);
+ silc_mp_pow_mod(&tmp, src, &key->dQ, &key->q);
+ silc_mp_mul(&tmp, &tmp, &key->pQ);
+ silc_mp_add(dst, dst, &tmp);
+ silc_mp_mod(dst, dst, &key->n);
+
+ silc_mp_uninit(&tmp);
+ }
+
+ return TRUE;
}
projects / silc.git / blobdiff