+++ /dev/null
-/*
- * PKCS #1 (RSA Encryption)
- * Copyright (c) 2006-2009, Jouni Malinen <j@w1.fi>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * Alternatively, this software may be distributed under the terms of BSD
- * license.
- *
- * See README and COPYING for more details.
- */
-
-#include "includes.h"
-
-#include "common.h"
-#include "rsa.h"
-#include "pkcs1.h"
-
-
-static int pkcs1_generate_encryption_block(u8 block_type, size_t modlen,
- const u8 *in, size_t inlen,
- u8 *out, size_t *outlen)
-{
- size_t ps_len;
- u8 *pos;
-
- /*
- * PKCS #1 v1.5, 8.1:
- *
- * EB = 00 || BT || PS || 00 || D
- * BT = 00 or 01 for private-key operation; 02 for public-key operation
- * PS = k-3-||D||; at least eight octets
- * (BT=0: PS=0x00, BT=1: PS=0xff, BT=2: PS=pseudorandom non-zero)
- * k = length of modulus in octets (modlen)
- */
-
- if (modlen < 12 || modlen > *outlen || inlen > modlen - 11) {
- wpa_printf(MSG_DEBUG, "PKCS #1: %s - Invalid buffer "
- "lengths (modlen=%lu outlen=%lu inlen=%lu)",
- __func__, (unsigned long) modlen,
- (unsigned long) *outlen,
- (unsigned long) inlen);
- return -1;
- }
-
- pos = out;
- *pos++ = 0x00;
- *pos++ = block_type; /* BT */
- ps_len = modlen - inlen - 3;
- switch (block_type) {
- case 0:
- os_memset(pos, 0x00, ps_len);
- pos += ps_len;
- break;
- case 1:
- os_memset(pos, 0xff, ps_len);
- pos += ps_len;
- break;
- case 2:
- if (os_get_random(pos, ps_len) < 0) {
- wpa_printf(MSG_DEBUG, "PKCS #1: %s - Failed to get "
- "random data for PS", __func__);
- return -1;
- }
- while (ps_len--) {
- if (*pos == 0x00)
- *pos = 0x01;
- pos++;
- }
- break;
- default:
- wpa_printf(MSG_DEBUG, "PKCS #1: %s - Unsupported block type "
- "%d", __func__, block_type);
- return -1;
- }
- *pos++ = 0x00;
- os_memcpy(pos, in, inlen); /* D */
-
- return 0;
-}
-
-
-int pkcs1_encrypt(int block_type, struct crypto_rsa_key *key,
- int use_private, const u8 *in, size_t inlen,
- u8 *out, size_t *outlen)
-{
- size_t modlen;
-
- modlen = crypto_rsa_get_modulus_len(key);
-
- if (pkcs1_generate_encryption_block(block_type, modlen, in, inlen,
- out, outlen) < 0)
- return -1;
-
- return crypto_rsa_exptmod(out, modlen, out, outlen, key, use_private);
-}
-
-
-int pkcs1_v15_private_key_decrypt(struct crypto_rsa_key *key,
- const u8 *in, size_t inlen,
- u8 *out, size_t *outlen)
-{
- int res;
- u8 *pos, *end;
-
- res = crypto_rsa_exptmod(in, inlen, out, outlen, key, 1);
- if (res)
- return res;
-
- if (*outlen < 2 || out[0] != 0 || out[1] != 2)
- return -1;
-
- /* Skip PS (pseudorandom non-zero octets) */
- pos = out + 2;
- end = out + *outlen;
- while (*pos && pos < end)
- pos++;
- if (pos == end)
- return -1;
- pos++;
-
- *outlen -= pos - out;
-
- /* Strip PKCS #1 header */
- os_memmove(out, pos, *outlen);
-
- return 0;
-}
-
-
-int pkcs1_decrypt_public_key(struct crypto_rsa_key *key,
- const u8 *crypt, size_t crypt_len,
- u8 *plain, size_t *plain_len)
-{
- size_t len;
- u8 *pos;
-
- len = *plain_len;
- if (crypto_rsa_exptmod(crypt, crypt_len, plain, &len, key, 0) < 0)
- return -1;
-
- /*
- * PKCS #1 v1.5, 8.1:
- *
- * EB = 00 || BT || PS || 00 || D
- * BT = 00 or 01
- * PS = k-3-||D|| times (00 if BT=00) or (FF if BT=01)
- * k = length of modulus in octets
- */
-
- if (len < 3 + 8 + 16 /* min hash len */ ||
- plain[0] != 0x00 || (plain[1] != 0x00 && plain[1] != 0x01)) {
- wpa_printf(MSG_INFO, "LibTomCrypt: Invalid signature EB "
- "structure");
- return -1;
- }
-
- pos = plain + 3;
- if (plain[1] == 0x00) {
- /* BT = 00 */
- if (plain[2] != 0x00) {
- wpa_printf(MSG_INFO, "LibTomCrypt: Invalid signature "
- "PS (BT=00)");
- return -1;
- }
- while (pos + 1 < plain + len && *pos == 0x00 && pos[1] == 0x00)
- pos++;
- } else {
- /* BT = 01 */
- if (plain[2] != 0xff) {
- wpa_printf(MSG_INFO, "LibTomCrypt: Invalid signature "
- "PS (BT=01)");
- return -1;
- }
- while (pos < plain + len && *pos == 0xff)
- pos++;
- }
-
- if (pos - plain - 2 < 8) {
- /* PKCS #1 v1.5, 8.1: At least eight octets long PS */
- wpa_printf(MSG_INFO, "LibTomCrypt: Too short signature "
- "padding");
- return -1;
- }
-
- if (pos + 16 /* min hash len */ >= plain + len || *pos != 0x00) {
- wpa_printf(MSG_INFO, "LibTomCrypt: Invalid signature EB "
- "structure (2)");
- return -1;
- }
- pos++;
- len -= pos - plain;
-
- /* Strip PKCS #1 header */
- os_memmove(plain, pos, len);
- *plain_len = len;
-
- return 0;
-}
projects / mech_eap.git / blobdiff