-/*
- * Copyright (C) 2011 Andre Noll <maan@tuebingen.mpg.de>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
+/* Copyright (C) 2011 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
/** \file gcrypt.c Libgrcypt-based encryption/decryption routines. */
}
/*
- * This is called at the beginning of every program that uses libgcrypt. We
- * don't have to initialize any random seed here, but we must initialize the
- * gcrypt library. This task is performed by gcry_check_version() which can
- * also check that the gcrypt library version is at least the minimal required
- * version.
+ * This is called at the beginning of every program that uses libgcrypt. The
+ * call to gcry_check_version() initializes the gcrypt library and checks that
+ * we have at least the minimal required version.
*/
void init_random_seed_or_die(void)
{
const char *req_ver = "1.5.0";
+ int seed;
- if (gcry_check_version(req_ver))
- return;
- PARA_EMERG_LOG("fatal: need at least libgcrypt-%s, have: %s\n",
- req_ver, gcry_check_version(NULL));
- exit(EXIT_FAILURE);
+ if (!gcry_check_version(req_ver)) {
+ PARA_EMERG_LOG("fatal: need at least libgcrypt-%s, have: %s\n",
+ req_ver, gcry_check_version(NULL));
+ exit(EXIT_FAILURE);
+ }
+ get_random_bytes_or_die((unsigned char *)&seed, sizeof(seed));
+ srandom(seed);
}
/** S-expression for the public part of an RSA key. */
return ret;
}
-static int get_ssh_public_key(unsigned char *data, int size, gcry_sexp_t *result)
+int get_public_key(const char *key_file, struct asymmetric_key **result)
{
+ unsigned char *blob, *p, *end;
int ret;
gcry_error_t gret;
- unsigned char *blob = NULL, *p, *end;
size_t nr_scanned, erroff, decoded_size;
- gcry_mpi_t e = NULL, n = NULL;
+ gcry_mpi_t e, n;
+ gcry_sexp_t sexp;
+ struct asymmetric_key *key;
- PARA_DEBUG_LOG("decoding %d byte public rsa-ssh key\n", size);
- ret = uudecode((char *)data, size, (char **)&blob, &decoded_size);
+ ret = decode_ssh_key(key_file, &blob, &decoded_size);
if (ret < 0)
- goto free_blob;
- end = blob + decoded_size;
- dump_buffer("decoded key", blob, decoded_size);
- ret = check_ssh_key_header(blob, decoded_size);
- if (ret < 0)
- goto free_blob;
+ return ret;
p = blob + ret;
- ret = -E_SSH_PARSE;
- if (p >= end)
- goto free_blob;
+ end = blob + decoded_size;
PARA_DEBUG_LOG("scanning modulus and public exponent\n");
gret = gcry_mpi_scan(&e, GCRYMPI_FMT_SSH, p, end - p, &nr_scanned);
if (gret) {
goto free_blob;
}
PARA_DEBUG_LOG("scanned e (%zu bytes)\n", nr_scanned);
-// gcry_mpi_aprint(GCRYMPI_FMT_HEX, &buf, NULL, rsa_e);
-// PARA_CRIT_LOG("e: %s\n", buf);
p += nr_scanned;
if (p >= end)
goto release_e;
goto release_e;
}
PARA_DEBUG_LOG("scanned n (%zu bytes)\n", nr_scanned);
-// gcry_mpi_aprint(GCRYMPI_FMT_HEX, &buf, NULL, rsa_n);
-// PARA_CRIT_LOG("n: %s\n", buf);
- gret = gcry_sexp_build(result, &erroff, RSA_PUBKEY_SEXP, n, e);
+ gret = gcry_sexp_build(&sexp, &erroff, RSA_PUBKEY_SEXP, n, e);
if (gret) {
PARA_ERROR_LOG("offset %zu: %s\n", erroff,
gcry_strerror(gcry_err_code(gret)));
}
ret = nr_scanned / 32 * 32;
PARA_INFO_LOG("successfully read %d bit ssh public key\n", ret * 8);
+ key = para_malloc(sizeof(*key));
+ key->num_bytes = ret;
+ key->sexp = sexp;
+ *result = key;
release_n:
gcry_mpi_release(n);
release_e:
return ret;
}
-int get_public_key(const char *key_file, struct asymmetric_key **result)
-{
- int ret, ret2;
- void *map;
- size_t map_size;
- unsigned char *start, *end;
- gcry_sexp_t sexp;
- struct asymmetric_key *key;
-
- ret = mmap_full_file(key_file, O_RDONLY, &map, &map_size, NULL);
- if (ret < 0)
- return ret;
- ret = is_ssh_rsa_key(map, map_size);
- if (!ret) {
- para_munmap(map, map_size);
- return -E_SSH_PARSE;
- }
- start = map + ret;
- end = map + map_size;
- ret = -E_SSH_PARSE;
- if (start >= end)
- goto unmap;
- ret = get_ssh_public_key(start, end - start, &sexp);
- if (ret < 0)
- goto unmap;
- key = para_malloc(sizeof(*key));
- key->num_bytes = ret;
- key->sexp = sexp;
- *result = key;
-unmap:
- ret2 = para_munmap(map, map_size);
- if (ret >= 0 && ret2 < 0)
- ret = ret2;
- return ret;
-}
-
void free_public_key(struct asymmetric_key *key)
{
if (!key)
gcry_cipher_hd_t handle;
};
-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)
{
gcry_error_t gret;
struct stream_cipher *sc = para_malloc(sizeof(*sc));
- if (use_aes) {
- assert(len >= 2 * AES_CRT128_BLOCK_SIZE);
- gret = gcry_cipher_open(&sc->handle, GCRY_CIPHER_AES128,
- GCRY_CIPHER_MODE_CTR, 0);
- assert(gret == 0);
- gret = gcry_cipher_setkey(sc->handle, data,
- AES_CRT128_BLOCK_SIZE);
- assert(gret == 0);
- gret = gcry_cipher_setctr(sc->handle,
- data + AES_CRT128_BLOCK_SIZE, AES_CRT128_BLOCK_SIZE);
- assert(gret == 0);
- return sc;
- }
- gret = gcry_cipher_open(&sc->handle, GCRY_CIPHER_ARCFOUR,
- GCRY_CIPHER_MODE_STREAM, 0);
- if (gret) {
- PARA_ERROR_LOG("%s\n", gcrypt_strerror(gret));
- free(sc);
- return NULL;
- }
- gret = gcry_cipher_setkey(sc->handle, data, (size_t)len);
+ assert(len >= 2 * AES_CRT128_BLOCK_SIZE);
+ gret = gcry_cipher_open(&sc->handle, GCRY_CIPHER_AES128,
+ GCRY_CIPHER_MODE_CTR, 0);
+ assert(gret == 0);
+ gret = gcry_cipher_setkey(sc->handle, data,
+ AES_CRT128_BLOCK_SIZE);
+ assert(gret == 0);
+ gret = gcry_cipher_setctr(sc->handle,
+ data + AES_CRT128_BLOCK_SIZE, AES_CRT128_BLOCK_SIZE);
assert(gret == 0);
return sc;
}