X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=crypt.c;h=06ae6265010a946bd51a1e64b1c620f0e4c89fc3;hp=5b7029d32d1aa906b8d5dae49a0e965af9d1c87f;hb=698178774b857a8959fe70e360ae6ff755eacf8e;hpb=4a4d8f266a79275d7b2c902dc69b5ec8d46406b2 diff --git a/crypt.c b/crypt.c index 5b7029d3..06ae6265 100644 --- a/crypt.c +++ b/crypt.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2005-2011 Andre Noll + * Copyright (C) 2005 Andre Noll * * Licensed under the GPL v2. For licencing details see COPYING. */ @@ -7,7 +7,6 @@ /** \file crypt.c Openssl-based encryption/decryption routines. */ #include -#include #include #include #include @@ -16,6 +15,7 @@ #include #include #include +#include #include "para.h" #include "error.h" @@ -148,8 +148,7 @@ static int read_rsa_bignums(const unsigned char *blob, int blen, RSA **result) *result = rsa; return 1; fail: - if (rsa) - RSA_free(rsa); + RSA_free(rsa); return ret; } @@ -184,24 +183,25 @@ int get_asymmetric_key(const char *key_file, int private, 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; + goto out_unmap; blob_size = 2 * map_size; blob = para_malloc(blob_size); ret = uudecode(cp, blob, blob_size); if (ret < 0) - goto out; + goto out_unmap; decoded_size = ret; ret = check_ssh_key_header(blob, decoded_size); if (ret < 0) - goto out; + goto out_unmap; ret = read_rsa_bignums(blob + ret, decoded_size - ret, &key->rsa); if (ret < 0) - goto out; + goto out_unmap; ret = RSA_size(key->rsa); -out: +out_unmap: ret2 = para_munmap(map, map_size); if (ret >= 0 && ret2 < 0) ret = ret2; +out: if (ret < 0) { free(key); *result = NULL; @@ -261,18 +261,35 @@ int pub_encrypt(struct asymmetric_key *pub, unsigned char *inbuf, } struct stream_cipher { - RC4_KEY key; + bool use_aes; + union { + RC4_KEY rc4_key; + EVP_CIPHER_CTX *aes; + } context; }; -struct stream_cipher *sc_new(const unsigned char *data, int len) +struct stream_cipher *sc_new(const unsigned char *data, int len, + bool use_aes) { struct stream_cipher *sc = para_malloc(sizeof(*sc)); - RC4_set_key(&sc->key, len, data); + + 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); + sc->context.aes = EVP_CIPHER_CTX_new(); + EVP_EncryptInit_ex(sc->context.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->context.aes); free(sc); } @@ -283,38 +300,53 @@ void sc_free(struct stream_cipher *sc) */ #define RC4_ALIGN 8 -int sc_send_bin_buffer(struct stream_cipher_context *scc, char *buf, - size_t len) +static void rc4_crypt(RC4_KEY *key, struct iovec *src, struct iovec *dst) { - int ret; - unsigned char *tmp; - static unsigned char remainder[RC4_ALIGN]; - size_t l1 = ROUND_DOWN(len, RC4_ALIGN), l2 = ROUND_UP(len, RC4_ALIGN); - - assert(len); - tmp = para_malloc(l2); - RC4(&scc->send->key, l1, (const unsigned char *)buf, tmp); + 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) { - memcpy(remainder, buf + l1, len - l1); - RC4(&scc->send->key, len - l1, remainder, tmp + l1); + unsigned char remainder[RC4_ALIGN] = ""; + memcpy(remainder, src->iov_base + l1, len - l1); + RC4(key, len - l1, remainder, dst->iov_base + l1); } - ret = write_all(scc->fd, (char *)tmp, &len); - free(tmp); - return ret; + ((char *)dst->iov_base)[len] = '\0'; } -int sc_recv_bin_buffer(struct stream_cipher_context *scc, char *buf, - size_t size) +static void aes_ctr128_crypt(EVP_CIPHER_CTX *ctx, struct iovec *src, + struct iovec *dst) { - unsigned char *tmp = para_malloc(size); - ssize_t ret = recv(scc->fd, tmp, size, 0); - - if (ret > 0) - RC4(&scc->recv->key, ret, tmp, (unsigned char *)buf); - else if (ret < 0) - ret = -ERRNO_TO_PARA_ERROR(errno); - free(tmp); - return ret; + int ret, inlen = src->iov_len, outlen, tmplen; + + *dst = (typeof(*dst)) { + /* Add one for the terminating zero byte. */ + .iov_base = para_malloc(inlen + 1), + .iov_len = inlen + }; + 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); } void hash_function(const char *data, unsigned long len, unsigned char *hash)