/*
cipher.c -- Symmetric block cipher handling
- Copyright (C) 2007 Guus Sliepen <guus@tinc-vpn.org>
+ Copyright (C) 2007-2012 Guus Sliepen <guus@tinc-vpn.org>
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
{NULL, GCRY_CIPHER_BLOWFISH, GCRY_CIPHER_MODE_CFB, 93},
{NULL, GCRY_CIPHER_BLOWFISH, GCRY_CIPHER_MODE_OFB, 94},
- {NULL, GCRY_CIPHER_AES, GCRY_CIPHER_MODE_ECB, 418},
- {"aes", GCRY_CIPHER_AES, GCRY_CIPHER_MODE_CBC, 419},
- {NULL, GCRY_CIPHER_AES, GCRY_CIPHER_MODE_CFB, 421},
- {NULL, GCRY_CIPHER_AES, GCRY_CIPHER_MODE_OFB, 420},
+ {"aes-128-ecb", GCRY_CIPHER_AES, GCRY_CIPHER_MODE_ECB, 418},
+ {"aes-128-cbc", GCRY_CIPHER_AES, GCRY_CIPHER_MODE_CBC, 419},
+ {"aes-128-cfb", GCRY_CIPHER_AES, GCRY_CIPHER_MODE_CFB, 421},
+ {"aes-128-ofb", GCRY_CIPHER_AES, GCRY_CIPHER_MODE_OFB, 420},
- {NULL, GCRY_CIPHER_AES192, GCRY_CIPHER_MODE_ECB, 422},
- {"aes192", GCRY_CIPHER_AES192, GCRY_CIPHER_MODE_CBC, 423},
- {NULL, GCRY_CIPHER_AES192, GCRY_CIPHER_MODE_CFB, 425},
- {NULL, GCRY_CIPHER_AES192, GCRY_CIPHER_MODE_OFB, 424},
+ {"aes-192-ecb", GCRY_CIPHER_AES192, GCRY_CIPHER_MODE_ECB, 422},
+ {"aes-192-cbc", GCRY_CIPHER_AES192, GCRY_CIPHER_MODE_CBC, 423},
+ {"aes-192-cfb", GCRY_CIPHER_AES192, GCRY_CIPHER_MODE_CFB, 425},
+ {"aes-192-ofb", GCRY_CIPHER_AES192, GCRY_CIPHER_MODE_OFB, 424},
- {NULL, GCRY_CIPHER_AES256, GCRY_CIPHER_MODE_ECB, 426},
- {"aes256", GCRY_CIPHER_AES256, GCRY_CIPHER_MODE_CBC, 427},
- {NULL, GCRY_CIPHER_AES256, GCRY_CIPHER_MODE_CFB, 429},
- {NULL, GCRY_CIPHER_AES256, GCRY_CIPHER_MODE_OFB, 428},
+ {"aes-256-ecb", GCRY_CIPHER_AES256, GCRY_CIPHER_MODE_ECB, 426},
+ {"aes-256-cbc", GCRY_CIPHER_AES256, GCRY_CIPHER_MODE_CBC, 427},
+ {"aes-256-cfb", GCRY_CIPHER_AES256, GCRY_CIPHER_MODE_CFB, 429},
+ {"aes-256-ofb", GCRY_CIPHER_AES256, GCRY_CIPHER_MODE_OFB, 428},
};
static bool nametocipher(const char *name, int *algo, int *mode) {
size_t i;
- for(i = 0; i < sizeof ciphertable / sizeof *ciphertable; i++) {
+ for(i = 0; i < sizeof(ciphertable) / sizeof(*ciphertable); i++) {
if(ciphertable[i].name && !strcasecmp(name, ciphertable[i].name)) {
*algo = ciphertable[i].algo;
*mode = ciphertable[i].mode;
static bool nidtocipher(int nid, int *algo, int *mode) {
size_t i;
- for(i = 0; i < sizeof ciphertable / sizeof *ciphertable; i++) {
+ for(i = 0; i < sizeof(ciphertable) / sizeof(*ciphertable); i++) {
if(nid == ciphertable[i].nid) {
*algo = ciphertable[i].algo;
*mode = ciphertable[i].mode;
static bool ciphertonid(int algo, int mode, int *nid) {
size_t i;
- for(i = 0; i < sizeof ciphertable / sizeof *ciphertable; i++) {
+ for(i = 0; i < sizeof(ciphertable) / sizeof(*ciphertable); i++) {
if(algo == ciphertable[i].algo && mode == ciphertable[i].mode) {
*nid = ciphertable[i].nid;
return true;
gcry_error_t err;
if(!ciphertonid(algo, mode, &cipher->nid)) {
- logger(LOG_DEBUG, "Cipher %d mode %d has no corresponding nid!", algo, mode);
+ logger(DEBUG_ALWAYS, LOG_DEBUG, "Cipher %d mode %d has no corresponding nid!", algo, mode);
return false;
}
if((err = gcry_cipher_open(&cipher->handle, algo, mode, 0))) {
- logger(LOG_DEBUG, "Unable to intialise cipher %d mode %d: %s", algo, mode, gcry_strerror(err));
+ logger(DEBUG_ALWAYS, LOG_DEBUG, "Unable to initialise cipher %d mode %d: %s", algo, mode, gcry_strerror(err));
return false;
}
int algo, mode;
if(!nametocipher(name, &algo, &mode)) {
- logger(LOG_DEBUG, "Unknown cipher name '%s'!", name);
+ logger(DEBUG_ALWAYS, LOG_DEBUG, "Unknown cipher name '%s'!", name);
return false;
}
int algo, mode;
if(!nidtocipher(nid, &algo, &mode)) {
- logger(LOG_DEBUG, "Unknown cipher ID %d!", nid);
+ logger(DEBUG_ALWAYS, LOG_DEBUG, "Unknown cipher ID %d!", nid);
return false;
}
cipher->handle = NULL;
}
- if(cipher->key) {
- free(cipher->key);
- cipher->key = NULL;
- }
+ free(cipher->key);
+
+ memset(cipher, 0, sizeof(*cipher));
}
size_t cipher_keylength(const cipher_t *cipher) {
+ if(!cipher) {
+ return 0;
+ }
+
return cipher->keylen + cipher->blklen;
}
+uint64_t cipher_budget(const cipher_t *cipher) {
+ if(!cipher) {
+ return UINT64_MAX; // NULL cipher
+ }
+
+ size_t ivlen = cipher->blklen;
+ size_t blklen = cipher->blklen;
+
+ size_t len = blklen > 1
+ ? blklen
+ : ivlen > 1 ? ivlen : 8;
+ size_t bits = len * 4 - 1;
+
+ return bits < 64
+ ? UINT64_C(1) << bits
+ : UINT64_MAX;
+}
+
+size_t cipher_blocksize(const cipher_t *cipher) {
+ if(!cipher || !cipher->blklen) {
+ return 1;
+ }
+
+ return cipher->blklen;
+}
+
void cipher_get_key(const cipher_t *cipher, void *key) {
memcpy(key, cipher->key, cipher->keylen + cipher->blklen);
}
}
bool cipher_set_key_from_rsa(cipher_t *cipher, void *key, size_t len, bool encrypt) {
- memcpy(cipher->key, key + len - cipher->keylen, cipher->keylen + cipher->blklen);
- memcpy(cipher->key + cipher->keylen, key + len - cipher->keylen - cipher->blklen, cipher->blklen);
-
+ memcpy(cipher->key,
+ key + len - cipher->keylen,
+ cipher->keylen);
gcry_cipher_setkey(cipher->handle, cipher->key, cipher->keylen);
+
+ memcpy(cipher->key + cipher->keylen,
+ key + len - cipher->blklen - cipher->keylen,
+ cipher->blklen);
gcry_cipher_setiv(cipher->handle, cipher->key + cipher->keylen, cipher->blklen);
return true;
uint8_t pad[cipher->blklen];
if(cipher->padding) {
- if(!oneshot)
+ if(!oneshot) {
+ return false;
+ }
+
+ size_t reqlen = ((inlen + cipher->blklen) / cipher->blklen) * cipher->blklen;
+
+ if(*outlen < reqlen) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Error while encrypting: not enough room for padding");
return false;
+ }
- size_t reqlen = ((inlen + 8) / cipher->blklen) * cipher->blklen;
uint8_t padbyte = reqlen - inlen;
inlen = reqlen - cipher->blklen;
for(int i = 0; i < cipher->blklen; i++)
- if(i < cipher->blklen - padbyte)
+ if(i < cipher->blklen - padbyte) {
pad[i] = ((uint8_t *)indata)[inlen + i];
- else
+ } else {
pad[i] = padbyte;
+ }
}
-
+
+ if(oneshot) {
+ gcry_cipher_setiv(cipher->handle, cipher->key + cipher->keylen, cipher->blklen);
+ }
+
if((err = gcry_cipher_encrypt(cipher->handle, outdata, *outlen, indata, inlen))) {
- logger(LOG_ERR, "Error while encrypting: %s", gcry_strerror(err));
+ logger(DEBUG_ALWAYS, LOG_ERR, "Error while encrypting: %s", gcry_strerror(err));
return false;
}
if(cipher->padding) {
if((err = gcry_cipher_encrypt(cipher->handle, outdata + inlen, cipher->blklen, pad, cipher->blklen))) {
- logger(LOG_ERR, "Error while encrypting: %s", gcry_strerror(err));
+ logger(DEBUG_ALWAYS, LOG_ERR, "Error while encrypting: %s", gcry_strerror(err));
return false;
}
bool cipher_decrypt(cipher_t *cipher, const void *indata, size_t inlen, void *outdata, size_t *outlen, bool oneshot) {
gcry_error_t err;
+ if(oneshot) {
+ gcry_cipher_setiv(cipher->handle, cipher->key + cipher->keylen, cipher->blklen);
+ }
+
if((err = gcry_cipher_decrypt(cipher->handle, outdata, *outlen, indata, inlen))) {
- logger(LOG_ERR, "Error while decrypting: %s", gcry_strerror(err));
+ logger(DEBUG_ALWAYS, LOG_ERR, "Error while decrypting: %s", gcry_strerror(err));
return false;
}
if(cipher->padding) {
- if(!oneshot)
+ if(!oneshot) {
return false;
+ }
uint8_t padbyte = ((uint8_t *)outdata)[inlen - 1];
if(padbyte == 0 || padbyte > cipher->blklen || padbyte > inlen) {
- logger(LOG_ERR, "Error while decrypting: invalid padding");
+ logger(DEBUG_ALWAYS, LOG_ERR, "Error while decrypting: invalid padding");
return false;
}
size_t origlen = inlen - padbyte;
- for(int i = inlen - 1; i >= origlen; i--)
+ for(size_t i = inlen - 1; i >= origlen; i--)
if(((uint8_t *)outdata)[i] != padbyte) {
- logger(LOG_ERR, "Error while decrypting: invalid padding");
+ logger(DEBUG_ALWAYS, LOG_ERR, "Error while decrypting: invalid padding");
return false;
}
*outlen = origlen;
+ } else {
+ *outlen = inlen;
}
return true;
}
int cipher_get_nid(const cipher_t *cipher) {
+ if(!cipher || !cipher->nid) {
+ return 0;
+ }
+
return cipher->nid;
}
projects / tinc / blobdiff