/**
* Converts a PEM encoded file into its binary form (RFC 1421, RFC 934)
*/
static status_t pem_to_bin(chunk_t *blob, bool *pgp)
{
typedef enum {
PEM_PRE = 0,
PEM_MSG = 1,
PEM_HEADER = 2,
PEM_BODY = 3,
PEM_POST = 4,
PEM_ABORT = 5
} state_t;
encryption_algorithm_t alg = ENCR_UNDEFINED;
size_t key_size = 0;
bool encrypted = FALSE;
state_t state = PEM_PRE;
chunk_t src = *blob;
chunk_t dst = *blob;
chunk_t line = chunk_empty;
chunk_t iv = chunk_empty;
u_char iv_buf[HASH_SIZE_MD5];
status_t status = NOT_FOUND;
enumerator_t *enumerator;
shared_key_t *shared;
dst.len = 0;
iv.ptr = iv_buf;
iv.len = 0;
while (fetchline(&src, &line))
{
if (state == PEM_PRE)
{
if (find_boundary("BEGIN", &line))
{
state = PEM_MSG;
}
continue;
}
else
{
if (find_boundary("END", &line))
{
state = PEM_POST;
break;
}
if (state == PEM_MSG)
{
state = PEM_HEADER;
if (memchr(line.ptr, ':', line.len) == NULL)
{
state = PEM_BODY;
}
}
if (state == PEM_HEADER)
{
err_t ugh = NULL;
chunk_t name = chunk_empty;
chunk_t value = chunk_empty;
/* an empty line separates HEADER and BODY */
if (line.len == 0)
{
state = PEM_BODY;
continue;
}
/* we are looking for a parameter: value pair */
DBG2(DBG_ASN, " %.*s", (int)line.len, line.ptr);
ugh = extract_parameter_value(&name, &value, &line);
if (ugh != NULL)
{
continue;
}
if (match("Proc-Type", &name) && *value.ptr == '4')
{
encrypted = TRUE;
}
else if (match("DEK-Info", &name))
{
chunk_t dek;
if (!extract_token(&dek, ',', &value))
{
dek = value;
}
if (match("DES-EDE3-CBC", &dek))
{
alg = ENCR_3DES;
key_size = 24;
}
else if (match("AES-128-CBC", &dek))
{
alg = ENCR_AES_CBC;
key_size = 16;
}
else if (match("AES-192-CBC", &dek))
{
alg = ENCR_AES_CBC;
key_size = 24;
}
else if (match("AES-256-CBC", &dek))
{
alg = ENCR_AES_CBC;
key_size = 32;
}
else
{
DBG1(DBG_ASN, " encryption algorithm '%.*s'"
" not supported", (int)dek.len, dek.ptr);
return NOT_SUPPORTED;
}
if (!eat_whitespace(&value) || value.len > 2*sizeof(iv_buf))
{
return PARSE_ERROR;
}
iv = chunk_from_hex(value, iv_buf);
}
}
else /* state is PEM_BODY */
{
chunk_t data;
/* remove any trailing whitespace */
if (!extract_token(&data ,' ', &line))
{
data = line;
}
/* check for PGP armor checksum */
if (*data.ptr == '=')
{
*pgp = TRUE;
data.ptr++;
data.len--;
DBG2(DBG_ASN, " armor checksum: %.*s", (int)data.len,
data.ptr);
continue;
}
if (blob->len - dst.len < data.len / 4 * 3)
{
state = PEM_ABORT;
}
data = chunk_from_base64(data, dst.ptr);
dst.ptr += data.len;
dst.len += data.len;
}
}
}
/* set length to size of binary blob */
blob->len = dst.len;
if (state != PEM_POST)
{
DBG1(DBG_LIB, " file coded in unknown format, discarded");
return PARSE_ERROR;
}
if (!encrypted)
{
return SUCCESS;
}
enumerator = lib->credmgr->create_shared_enumerator(lib->credmgr,
SHARED_PRIVATE_KEY_PASS, NULL, NULL);
while (enumerator->enumerate(enumerator, &shared, NULL, NULL))
{
chunk_t passphrase, chunk;
passphrase = shared->get_key(shared);
chunk = chunk_clone(*blob);
status = pem_decrypt(&chunk, alg, key_size, iv, passphrase);
if (status == SUCCESS)
{
memcpy(blob->ptr, chunk.ptr, chunk.len);
blob->len = chunk.len;
}
free(chunk.ptr);
if (status != INVALID_ARG)
{ /* try again only if passphrase invalid */
break;
}
}
enumerator->destroy(enumerator);
return status;
}
/* Converts a PEM encoded file into its binary form
*
* RFC 1421 Privacy Enhancement for Electronic Mail, February 1993
* RFC 934 Message Encapsulation, January 1985
*/
err_t pem_to_bin(chunk_t *blob, chunk_t *passphrase, bool *pgp)
{
typedef enum {
PEM_PRE = 0,
PEM_MSG = 1,
PEM_HEADER = 2,
PEM_BODY = 3,
PEM_POST = 4,
PEM_ABORT = 5
} state_t;
encryption_algorithm_t alg = ENCR_UNDEFINED;
size_t key_size = 0;
bool encrypted = FALSE;
state_t state = PEM_PRE;
chunk_t src = *blob;
chunk_t dst = *blob;
chunk_t line = CHUNK_INITIALIZER;
chunk_t iv = CHUNK_INITIALIZER;
u_char iv_buf[16]; /* MD5 digest size */
/* zero size of converted blob */
dst.len = 0;
/* zero size of IV */
iv.ptr = iv_buf;
iv.len = 0;
pem_init_logger();
while (fetchline(&src, &line))
{
if (state == PEM_PRE)
{
if (find_boundary("BEGIN", &line))
{
state = PEM_MSG;
}
continue;
}
else
{
if (find_boundary("END", &line))
{
state = PEM_POST;
break;
}
if (state == PEM_MSG)
{
state = (memchr(line.ptr, ':', line.len) == NULL) ? PEM_BODY : PEM_HEADER;
}
if (state == PEM_HEADER)
{
err_t ugh = NULL;
chunk_t name = CHUNK_INITIALIZER;
chunk_t value = CHUNK_INITIALIZER;
/* an empty line separates HEADER and BODY */
if (line.len == 0)
{
state = PEM_BODY;
continue;
}
/* we are looking for a parameter: value pair */
logger->log(logger, CONTROL|LEVEL2, " %.*s", (int)line.len, line.ptr);
ugh = extract_parameter_value(&name, &value, &line);
if (ugh != NULL)
continue;
if (match("Proc-Type", &name) && *value.ptr == '4')
encrypted = TRUE;
else if (match("DEK-Info", &name))
{
size_t len = 0;
chunk_t dek;
if (!extract_token(&dek, ',', &value))
dek = value;
/* we support DES-EDE3-CBC encrypted files, only */
if (match("DES-EDE3-CBC", &dek))
{
alg = ENCR_3DES;
key_size = 24;
}
else if (match("AES-128-CBC", &dek))
{
alg = ENCR_AES_CBC;
key_size = 16;
}
else if (match("AES-192-CBC", &dek))
{
alg = ENCR_AES_CBC;
key_size = 24;
}
else if (match("AES-256-CBC", &dek))
{
alg = ENCR_AES_CBC;
key_size = 32;
}
else
{
return "encryption algorithm not supported";
}
eat_whitespace(&value);
ugh = ttodata(value.ptr, value.len, 16, iv.ptr, 16, &len);
if (ugh)
return "error in IV";
iv.len = len;
}
}
else /* state is PEM_BODY */
{
const char *ugh = NULL;
size_t len = 0;
chunk_t data;
/* remove any trailing whitespace */
if (!extract_token(&data ,' ', &line))
{
data = line;
}
/* check for PGP armor checksum */
if (*data.ptr == '=')
{
*pgp = TRUE;
data.ptr++;
data.len--;
logger->log(logger, CONTROL|LEVEL2, " Armor checksum: %.*s",
(int)data.len, data.ptr);
continue;
}
ugh = ttodata(data.ptr, data.len, 64, dst.ptr, blob->len - dst.len, &len);
if (ugh)
{
state = PEM_ABORT;
break;
}
else
{
dst.ptr += len;
dst.len += len;
}
}
}
}
/* set length to size of binary blob */
blob->len = dst.len;
if (state != PEM_POST)
return "file coded in unknown format, discarded";
return (encrypted)? pem_decrypt(blob, alg, key_size, &iv, passphrase) : NULL;
}
/**
* Converts a PEM encoded file into its binary form (RFC 1421, RFC 934)
*/
static status_t pem_to_bin(chunk_t *blob, chunk_t(*cb)(void*,int), void *cb_data,
bool *pgp)
{
typedef enum {
PEM_PRE = 0,
PEM_MSG = 1,
PEM_HEADER = 2,
PEM_BODY = 3,
PEM_POST = 4,
PEM_ABORT = 5
} state_t;
encryption_algorithm_t alg = ENCR_UNDEFINED;
size_t key_size = 0;
bool encrypted = FALSE;
state_t state = PEM_PRE;
chunk_t src = *blob;
chunk_t dst = *blob;
chunk_t line = chunk_empty;
chunk_t iv = chunk_empty;
chunk_t passphrase;
int try = 0;
u_char iv_buf[HASH_SIZE_MD5];
dst.len = 0;
iv.ptr = iv_buf;
iv.len = 0;
while (fetchline(&src, &line))
{
if (state == PEM_PRE)
{
if (find_boundary("BEGIN", &line))
{
state = PEM_MSG;
}
continue;
}
else
{
if (find_boundary("END", &line))
{
state = PEM_POST;
break;
}
if (state == PEM_MSG)
{
state = PEM_HEADER;
if (memchr(line.ptr, ':', line.len) == NULL)
{
state = PEM_BODY;
}
}
if (state == PEM_HEADER)
{
err_t ugh = NULL;
chunk_t name = chunk_empty;
chunk_t value = chunk_empty;
/* an empty line separates HEADER and BODY */
if (line.len == 0)
{
state = PEM_BODY;
continue;
}
/* we are looking for a parameter: value pair */
DBG2(DBG_LIB, " %.*s", (int)line.len, line.ptr);
ugh = extract_parameter_value(&name, &value, &line);
if (ugh != NULL)
{
continue;
}
if (match("Proc-Type", &name) && *value.ptr == '4')
{
encrypted = TRUE;
}
else if (match("DEK-Info", &name))
{
chunk_t dek;
if (!extract_token(&dek, ',', &value))
{
dek = value;
}
if (match("DES-EDE3-CBC", &dek))
{
alg = ENCR_3DES;
key_size = 24;
}
else if (match("AES-128-CBC", &dek))
{
alg = ENCR_AES_CBC;
key_size = 16;
}
else if (match("AES-192-CBC", &dek))
{
alg = ENCR_AES_CBC;
key_size = 24;
}
else if (match("AES-256-CBC", &dek))
{
alg = ENCR_AES_CBC;
key_size = 32;
}
else
{
DBG1(DBG_LIB, " encryption algorithm '%.*s'"
" not supported", dek.len, dek.ptr);
return NOT_SUPPORTED;
}
eat_whitespace(&value);
iv = chunk_from_hex(value, iv.ptr);
}
}
else /* state is PEM_BODY */
{
chunk_t data;
/* remove any trailing whitespace */
if (!extract_token(&data ,' ', &line))
{
data = line;
}
/* check for PGP armor checksum */
if (*data.ptr == '=')
{
*pgp = TRUE;
data.ptr++;
data.len--;
DBG2(DBG_LIB, " armor checksum: %.*s", (int)data.len,
data.ptr);
continue;
}
if (blob->len - dst.len < data.len / 4 * 3)
{
state = PEM_ABORT;
}
data = chunk_from_base64(data, dst.ptr);
dst.ptr += data.len;
dst.len += data.len;
}
}
}
/* set length to size of binary blob */
blob->len = dst.len;
if (state != PEM_POST)
{
DBG1(DBG_LIB, " file coded in unknown format, discarded");
return PARSE_ERROR;
}
if (!encrypted)
{
return SUCCESS;
}
if (!cb)
{
DBG1(DBG_LIB, " missing passphrase");
return INVALID_ARG;
}
while (TRUE)
{
passphrase = cb(cb_data, ++try);
if (!passphrase.len || !passphrase.ptr)
{
return INVALID_ARG;
}
switch (pem_decrypt(blob, alg, key_size, iv, passphrase))
{
case INVALID_ARG:
/* bad passphrase, retry */
continue;
case SUCCESS:
return SUCCESS;
default:
return FAILED;
}
}
}
