-/*
- * Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
+/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
/** \file crypt.c Openssl-based encryption/decryption routines. */
#include <sys/socket.h>
#include <openssl/rand.h>
#include <openssl/err.h>
-#include <openssl/rc4.h>
#include <openssl/pem.h>
#include <openssl/sha.h>
#include <openssl/bn.h>
#include "crypt.h"
#include "fd.h"
#include "crypt_backend.h"
+#include "base64.h"
+#include "portable_io.h"
struct asymmetric_key {
RSA *rsa;
srandom(seed);
}
-static EVP_PKEY *load_key(const char *file, int private)
-{
- BIO *key;
- EVP_PKEY *pkey = NULL;
- int ret = check_key_file(file, private);
-
- if (ret < 0) {
- PARA_ERROR_LOG("%s\n", para_strerror(-ret));
- return NULL;
- }
- key = BIO_new(BIO_s_file());
- if (!key)
- return NULL;
- if (BIO_read_filename(key, file) > 0) {
- if (private == LOAD_PRIVATE_KEY)
- pkey = PEM_read_bio_PrivateKey(key, NULL, NULL, NULL);
- else
- pkey = PEM_read_bio_PUBKEY(key, NULL, NULL, NULL);
- }
- BIO_free(key);
- return pkey;
-}
-
-static int get_openssl_key(const char *key_file, RSA **rsa, int private)
+static int get_private_key(const char *path, RSA **rsa)
{
- EVP_PKEY *key = load_key(key_file, private);
-
- if (!key)
- return (private == LOAD_PRIVATE_KEY)? -E_PRIVATE_KEY
- : -E_PUBLIC_KEY;
- *rsa = EVP_PKEY_get1_RSA(key);
- EVP_PKEY_free(key);
- if (!*rsa)
- return -E_RSA;
- return RSA_size(*rsa);
+ EVP_PKEY *pkey;
+ BIO *bio = BIO_new(BIO_s_file());
+
+ *rsa = NULL;
+ if (!bio)
+ return -E_PRIVATE_KEY;
+ if (BIO_read_filename(bio, path) <= 0)
+ goto bio_free;
+ pkey = PEM_read_bio_PrivateKey(bio, NULL, NULL, NULL);
+ if (!pkey)
+ goto bio_free;
+ *rsa = EVP_PKEY_get1_RSA(pkey);
+ EVP_PKEY_free(pkey);
+bio_free:
+ BIO_free(bio);
+ return *rsa? RSA_size(*rsa) : -E_PRIVATE_KEY;
}
/*
return -E_BIGNUM;
if (p + 4 > end)
return -E_BIGNUM;
- bnsize = read_ssh_u32(p);
+ bnsize = read_u32_be(p);
PARA_DEBUG_LOG("bnsize: %u\n", bnsize);
p += 4;
if (p + bnsize < p)
{
int ret;
RSA *rsa;
+ BIGNUM *n, *e;
const unsigned char *p = blob, *end = blob + blen;
rsa = RSA_new();
if (!rsa)
return -E_BIGNUM;
- ret = read_bignum(p, end - p, &rsa->e);
+ ret = read_bignum(p, end - p, &e);
if (ret < 0)
goto fail;
p += ret;
- ret = read_bignum(p, end - p, &rsa->n);
+ ret = read_bignum(p, end - p, &n);
if (ret < 0)
goto fail;
+#ifdef HAVE_RSA_SET0_KEY
+ RSA_set0_key(rsa, n, e, NULL);
+#else
+ rsa->n = n;
+ rsa->e = e;
+#endif
*result = rsa;
return 1;
fail:
return ret;
}
-int get_asymmetric_key(const char *key_file, int private,
- struct asymmetric_key **result)
+int get_public_key(const char *key_file, struct asymmetric_key **result)
{
struct asymmetric_key *key = NULL;
void *map = NULL;
unsigned char *blob = NULL;
- size_t map_size, blob_size, decoded_size;
+ size_t map_size, encoded_size, decoded_size;
int ret, ret2;
char *cp;
key = para_malloc(sizeof(*key));
- if (private) {
- ret = get_openssl_key(key_file, &key->rsa, LOAD_PRIVATE_KEY);
- goto out;
- }
ret = mmap_full_file(key_file, O_RDONLY, &map, &map_size, NULL);
if (ret < 0)
goto out;
ret = is_ssh_rsa_key(map, map_size);
if (!ret) {
- ret = para_munmap(map, map_size);
- map = NULL;
- if (ret < 0)
- goto out;
- ret = get_openssl_key(key_file, &key->rsa, LOAD_PUBLIC_KEY);
- goto out;
+ para_munmap(map, map_size);
+ return -E_SSH_PARSE;
}
cp = map + ret;
+ encoded_size = map_size - ret;
PARA_INFO_LOG("decoding public rsa-ssh key %s\n", key_file);
- ret = -ERRNO_TO_PARA_ERROR(EOVERFLOW);
- if (map_size > INT_MAX / 4)
- goto out_unmap;
- blob_size = 2 * map_size;
- blob = para_malloc(blob_size);
- ret = uudecode(cp, blob, blob_size);
+ ret = uudecode(cp, encoded_size, (char **)&blob, &decoded_size);
if (ret < 0)
goto out_unmap;
- decoded_size = ret;
ret = check_ssh_key_header(blob, decoded_size);
if (ret < 0)
goto out_unmap;
return ret;
}
-void free_asymmetric_key(struct asymmetric_key *key)
+void free_public_key(struct asymmetric_key *key)
{
if (!key)
return;
struct asymmetric_key *priv;
int ret;
+ ret = check_private_key_file(key_file);
+ if (ret < 0)
+ return ret;
if (inlen < 0)
return -E_RSA;
- ret = get_asymmetric_key(key_file, LOAD_PRIVATE_KEY, &priv);
- if (ret < 0)
+ priv = para_malloc(sizeof(*priv));
+ ret = get_private_key(key_file, &priv->rsa);
+ if (ret < 0) {
+ free(priv);
return ret;
+ }
/*
* RSA is vulnerable to timing attacks. Generate a random blinding
* factor to protect against this kind of attack.
if (ret <= 0)
ret = -E_DECRYPT;
out:
- free_asymmetric_key(priv);
+ RSA_free(priv->rsa);
+ free(priv);
return ret;
}
return ret < 0? -E_ENCRYPT : ret;
}
-struct aes_ctr_128_context {
- AES_KEY key;
- unsigned char ivec[AES_CRT128_BLOCK_SIZE];
- unsigned char ecount[AES_CRT128_BLOCK_SIZE];
- unsigned int num;
-};
-
struct stream_cipher {
- bool use_aes;
- union {
- RC4_KEY rc4_key;
- struct aes_ctr_128_context aes;
- } context;
+ EVP_CIPHER_CTX *aes;
};
-struct stream_cipher *sc_new(const unsigned char *data, int len,
- bool use_aes)
+struct stream_cipher *sc_new(const unsigned char *data, int len)
{
- int ret;
struct stream_cipher *sc = para_malloc(sizeof(*sc));
- struct aes_ctr_128_context *aes;
- sc->use_aes = use_aes;
- if (!use_aes) {
- RC4_set_key(&sc->context.rc4_key, len, data);
- return sc;
- }
assert(len >= 2 * AES_CRT128_BLOCK_SIZE);
- aes = &sc->context.aes;
- ret = AES_set_encrypt_key(data, AES_CRT128_BLOCK_SIZE * 8 /* bits */,
- &aes->key);
- assert(ret == 0);
- memcpy(aes->ivec, data + AES_CRT128_BLOCK_SIZE, AES_CRT128_BLOCK_SIZE);
- aes->num = 0;
+ sc->aes = EVP_CIPHER_CTX_new();
+ EVP_EncryptInit_ex(sc->aes, EVP_aes_128_ctr(), NULL, data,
+ data + AES_CRT128_BLOCK_SIZE);
return sc;
}
void sc_free(struct stream_cipher *sc)
{
+ if (!sc)
+ return;
+ EVP_CIPHER_CTX_free(sc->aes);
free(sc);
}
-/**
- * The RC4() implementation of openssl apparently reads and writes data in
- * blocks of 8 bytes. So we have to make sure our buffer sizes are a multiple
- * of this.
- */
-#define RC4_ALIGN 8
-
-static void rc4_crypt(RC4_KEY *key, struct iovec *src, struct iovec *dst)
-{
- size_t len = src->iov_len, l1, l2;
-
- assert(len > 0);
- assert(len < ((typeof(src->iov_len))-1) / 2);
- l1 = ROUND_DOWN(len, RC4_ALIGN);
- l2 = ROUND_UP(len, RC4_ALIGN);
-
- *dst = (typeof(*dst)) {
- /* Add one for the terminating zero byte. */
- .iov_base = para_malloc(l2 + 1),
- .iov_len = len
- };
- RC4(key, l1, src->iov_base, dst->iov_base);
- if (len > l1) {
- unsigned char remainder[RC4_ALIGN] = "";
- memcpy(remainder, src->iov_base + l1, len - l1);
- RC4(key, len - l1, remainder, dst->iov_base + l1);
- }
- ((char *)dst->iov_base)[len] = '\0';
-}
-
-static void aes_ctr128_crypt(struct aes_ctr_128_context *aes, struct iovec *src,
+static void aes_ctr128_crypt(EVP_CIPHER_CTX *ctx, struct iovec *src,
struct iovec *dst)
{
- size_t len = src->iov_len;
+ int ret, inlen = src->iov_len, outlen, tmplen;
*dst = (typeof(*dst)) {
/* Add one for the terminating zero byte. */
- .iov_base = para_malloc(len + 1),
- .iov_len = len
+ .iov_base = para_malloc(inlen + 1),
+ .iov_len = inlen
};
- AES_ctr128_encrypt(src->iov_base, dst->iov_base, len,
- &aes->key, aes->ivec, aes->ecount, &aes->num);
- ((char *)dst->iov_base)[len] = '\0';
+ ret = EVP_EncryptUpdate(ctx, dst->iov_base, &outlen, src->iov_base, inlen);
+ assert(ret != 0);
+ ret = EVP_EncryptFinal_ex(ctx, dst->iov_base + outlen, &tmplen);
+ assert(ret != 0);
+ outlen += tmplen;
+ ((char *)dst->iov_base)[outlen] = '\0';
+ dst->iov_len = outlen;
}
void sc_crypt(struct stream_cipher *sc, struct iovec *src, struct iovec *dst)
{
- if (sc->use_aes)
- return aes_ctr128_crypt(&sc->context.aes, src, dst);
- return rc4_crypt(&sc->context.rc4_key, src, dst);
+ return aes_ctr128_crypt(sc->aes, src, dst);
}
void hash_function(const char *data, unsigned long len, unsigned char *hash)