X-Git-Url: https://www.tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fopenssl%2Fcipher.c;h=5172d82e69b81c3cd439f8d48b263e4b44345f55;hb=9b2eaebdf6eb46321403bfc6af1145d051d3bbdc;hp=553b4adb4e2a6fc823ab51753283806a6336e01d;hpb=70a1a5594af5d4e6a364186b42ba4e34c676009b;p=tinc diff --git a/src/openssl/cipher.c b/src/openssl/cipher.c index 553b4adb..5172d82e 100644 --- a/src/openssl/cipher.c +++ b/src/openssl/cipher.c @@ -1,6 +1,6 @@ /* cipher.c -- Symmetric block cipher handling - Copyright (C) 2007-2012 Guus Sliepen + Copyright (C) 2007-2013 Guus Sliepen 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 @@ -17,60 +17,74 @@ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ -#include "system.h" +#include "../system.h" #include #include +#include -#include "cipher.h" -#include "logger.h" -#include "xalloc.h" +#include "../cipher.h" +#include "../logger.h" +#include "../xalloc.h" + +struct cipher { + EVP_CIPHER_CTX ctx; + const EVP_CIPHER *cipher; + struct cipher_counter *counter; +}; typedef struct cipher_counter { - unsigned char counter[EVP_MAX_IV_LENGTH]; - unsigned char block[EVP_MAX_IV_LENGTH]; + unsigned char counter[CIPHER_MAX_IV_SIZE]; + unsigned char block[CIPHER_MAX_IV_SIZE]; int n; } cipher_counter_t; -static bool cipher_open(cipher_t *cipher) { +static cipher_t *cipher_open(const EVP_CIPHER *evp_cipher) { + cipher_t *cipher = xzalloc(sizeof *cipher); + cipher->cipher = evp_cipher; EVP_CIPHER_CTX_init(&cipher->ctx); - return true; + return cipher; } -bool cipher_open_by_name(cipher_t *cipher, const char *name) { - cipher->cipher = EVP_get_cipherbyname(name); - - if(cipher->cipher) - return cipher_open(cipher); +cipher_t *cipher_open_by_name(const char *name) { + const EVP_CIPHER *evp_cipher = EVP_get_cipherbyname(name); + if(!evp_cipher) { + logger(DEBUG_ALWAYS, LOG_ERR, "Unknown cipher name '%s'!", name); + return NULL; + } - logger(DEBUG_ALWAYS, LOG_ERR, "Unknown cipher name '%s'!", name); - return false; + return cipher_open(evp_cipher); } -bool cipher_open_by_nid(cipher_t *cipher, int nid) { - cipher->cipher = EVP_get_cipherbynid(nid); - - if(cipher->cipher) - return cipher_open(cipher); +cipher_t *cipher_open_by_nid(int nid) { + const EVP_CIPHER *evp_cipher = EVP_get_cipherbynid(nid); + if(!evp_cipher) { + logger(DEBUG_ALWAYS, LOG_ERR, "Unknown cipher nid %d!", nid); + return NULL; + } - logger(DEBUG_ALWAYS, LOG_ERR, "Unknown cipher nid %d!", nid); - return false; + return cipher_open(evp_cipher); } -bool cipher_open_blowfish_ofb(cipher_t *cipher) { - cipher->cipher = EVP_bf_ofb(); - return cipher_open(cipher); +cipher_t *cipher_open_blowfish_ofb(void) { + return cipher_open(EVP_bf_ofb()); } void cipher_close(cipher_t *cipher) { + if(!cipher) + return; + EVP_CIPHER_CTX_cleanup(&cipher->ctx); free(cipher->counter); - cipher->counter = NULL; + free(cipher); } size_t cipher_keylength(const cipher_t *cipher) { - return cipher->cipher->key_len + cipher->cipher->block_size; + if(!cipher || !cipher->cipher) + return 0; + + return cipher->cipher->key_len + cipher->cipher->iv_len; } bool cipher_set_key(cipher_t *cipher, void *key, bool encrypt) { @@ -104,13 +118,12 @@ bool cipher_set_key_from_rsa(cipher_t *cipher, void *key, size_t len, bool encry } bool cipher_set_counter(cipher_t *cipher, const void *counter, size_t len) { - if(len > cipher->cipher->block_size - 4) { + if(len > cipher->cipher->iv_len - 4) { logger(DEBUG_ALWAYS, LOG_ERR, "Counter too long"); - abort(); + return false; } - memcpy(cipher->counter->counter + cipher->cipher->block_size - len, counter, len); - memset(cipher->counter->counter, 0, 4); + memcpy(cipher->counter->counter, counter, len); cipher->counter->n = 0; return true; @@ -124,45 +137,100 @@ bool cipher_set_counter_key(cipher_t *cipher, void *key) { } if(!cipher->counter) - cipher->counter = xmalloc_and_zero(sizeof *cipher->counter); + cipher->counter = xzalloc(sizeof *cipher->counter); else cipher->counter->n = 0; - memcpy(cipher->counter->counter, (unsigned char *)key + cipher->cipher->key_len, cipher->cipher->block_size); + memcpy(cipher->counter->counter, (unsigned char *)key + cipher->cipher->key_len, cipher->cipher->iv_len); return true; } -bool cipher_counter_xor(cipher_t *cipher, const void *indata, size_t inlen, void *outdata) { - if(!cipher->counter) { - logger(DEBUG_ALWAYS, LOG_ERR, "Counter not initialized"); +bool cipher_gcm_encrypt_start(cipher_t *cipher, const void *indata, size_t inlen, void *outdata, size_t *outlen) { + int len = 0; + if(!EVP_EncryptInit_ex(&cipher->ctx, NULL, NULL, NULL, cipher->counter->counter) + || (inlen && !EVP_EncryptUpdate(&cipher->ctx, (unsigned char *)outdata, &len, (unsigned char *)indata, inlen))) { + logger(DEBUG_ALWAYS, LOG_ERR, "Error while encrypting: %s", ERR_error_string(ERR_get_error(), NULL)); return false; } + if(outlen) + *outlen = len; + return true; +} - const unsigned char *in = indata; - unsigned char *out = outdata; - - while(inlen--) { - // Encrypt the new counter value if we need it - if(!cipher->counter->n) { - int len; - if(!EVP_EncryptUpdate(&cipher->ctx, cipher->counter->block, &len, cipher->counter->counter, cipher->cipher->block_size)) { - logger(DEBUG_ALWAYS, LOG_ERR, "Error while encrypting: %s", ERR_error_string(ERR_get_error(), NULL)); - return false; - } - - // Increase the counter value - for(int i = 0; i < cipher->cipher->block_size; i++) - if(++cipher->counter->counter[i]) - break; - } +bool cipher_gcm_encrypt_finish(cipher_t *cipher, const void *indata, size_t inlen, void *outdata, size_t *outlen) { + int len = 0, pad = 0; + if((inlen && !EVP_EncryptUpdate(&cipher->ctx, (unsigned char *)outdata, &len, (unsigned char *)indata, inlen)) + || !EVP_EncryptFinal(&cipher->ctx, (unsigned char *)outdata + len, &pad)) { + logger(DEBUG_ALWAYS, LOG_ERR, "Error while encrypting: %s", ERR_error_string(ERR_get_error(), NULL)); + return false; + } + EVP_CIPHER_CTX_ctrl(&cipher->ctx, EVP_CTRL_GCM_GET_TAG, 16, (unsigned char *)outdata + len + pad); + if(outlen) + *outlen = len + pad + 16; + return true; +} + +bool cipher_gcm_encrypt(cipher_t *cipher, const void *indata, size_t inlen, void *outdata, size_t *outlen) { + int len = 0, pad = 0; + if(!EVP_EncryptInit_ex(&cipher->ctx, NULL, NULL, NULL, cipher->counter->counter) || + !EVP_EncryptUpdate(&cipher->ctx, (unsigned char *)outdata, &len, (unsigned char *)indata, inlen) || + !EVP_EncryptFinal(&cipher->ctx, (unsigned char *)outdata + len, &pad)) { + logger(DEBUG_ALWAYS, LOG_ERR, "Error while encrypting: %s", ERR_error_string(ERR_get_error(), NULL)); + return false; + } + EVP_CIPHER_CTX_ctrl(&cipher->ctx, EVP_CTRL_GCM_GET_TAG, 16, (unsigned char *)outdata + len + pad); + if(outlen) + *outlen = len + pad + 16; + return true; +} - *out++ = *in++ ^ cipher->counter->counter[cipher->counter->n++]; +bool cipher_gcm_decrypt(cipher_t *cipher, const void *indata, size_t inlen, void *outdata, size_t *outlen) { + if(inlen < 16) + return false; - if(cipher->counter->n >= cipher->cipher->block_size) - cipher->counter->n = 0; + int len = 0, pad = 0; + if(!EVP_DecryptInit_ex(&cipher->ctx, NULL, NULL, NULL, cipher->counter->counter)) { + logger(DEBUG_ALWAYS, LOG_ERR, "Error while decrypting: %s", ERR_error_string(ERR_get_error(), NULL)); + return false; } + EVP_CIPHER_CTX_ctrl(&cipher->ctx, EVP_CTRL_GCM_SET_TAG, 16, (unsigned char *)indata + inlen - 16); + + if(!EVP_DecryptUpdate(&cipher->ctx, (unsigned char *)outdata, &len, (unsigned char *)indata, inlen - 16) || + !EVP_DecryptFinal(&cipher->ctx, (unsigned char *)outdata + len, &pad)) { + logger(DEBUG_ALWAYS, LOG_ERR, "Error while decrypting: %s", ERR_error_string(ERR_get_error(), NULL)); + return false; + } + if(outlen) + *outlen = len; + return true; +} + +bool cipher_gcm_decrypt_start(cipher_t *cipher, const void *indata, size_t inlen, void *outdata, size_t *outlen) { + int len = 0; + if(!EVP_DecryptInit_ex(&cipher->ctx, NULL, NULL, NULL, cipher->counter->counter) + || (inlen && !EVP_DecryptUpdate(&cipher->ctx, (unsigned char *)outdata, &len, (unsigned char *)indata, inlen))) { + logger(DEBUG_ALWAYS, LOG_ERR, "Error while decrypting: %s", ERR_error_string(ERR_get_error(), NULL)); + return false; + } + if(outlen) + *outlen = len; + return true; +} + +bool cipher_gcm_decrypt_finish(cipher_t *cipher, const void *indata, size_t inlen, void *outdata, size_t *outlen) { + if(inlen < 16) + return false; + + EVP_CIPHER_CTX_ctrl(&cipher->ctx, EVP_CTRL_GCM_SET_TAG, 16, (unsigned char *)indata + inlen - 16); + + int len = 0, pad = 0; + if((inlen > 16 && !EVP_DecryptUpdate(&cipher->ctx, (unsigned char *)outdata, &len, (unsigned char *)indata, inlen - 16)) + || !EVP_DecryptFinal(&cipher->ctx, (unsigned char *)outdata + len, &pad)) { + logger(DEBUG_ALWAYS, LOG_ERR, "Error while decrypting: %s", ERR_error_string(ERR_get_error(), NULL)); + return false; + } return true; } @@ -210,9 +278,12 @@ bool cipher_decrypt(cipher_t *cipher, const void *indata, size_t inlen, void *ou } int cipher_get_nid(const cipher_t *cipher) { - return cipher->cipher ? cipher->cipher->nid : 0; + if(!cipher || !cipher->cipher) + return 0; + + return cipher->cipher->nid; } bool cipher_active(const cipher_t *cipher) { - return cipher->cipher && cipher->cipher->nid != 0; + return cipher && cipher->cipher && cipher->cipher->nid != 0; }