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|
#include "fitz.h"
#include "mupdf.h"
enum
{
PDF_CRYPT_NONE,
PDF_CRYPT_RC4,
PDF_CRYPT_AESV2,
PDF_CRYPT_AESV3,
PDF_CRYPT_UNKNOWN,
};
typedef struct pdf_crypt_filter_s pdf_crypt_filter;
struct pdf_crypt_filter_s
{
int method;
int length;
};
struct pdf_crypt_s
{
fz_obj *id;
int v;
int length;
fz_obj *cf;
pdf_crypt_filter stmf;
pdf_crypt_filter strf;
int r;
unsigned char o[48];
unsigned char u[48];
unsigned char oe[32];
unsigned char ue[32];
int p;
int encrypt_metadata;
unsigned char key[32]; /* decryption key generated from password */
};
static fz_error pdf_parse_crypt_filter(pdf_crypt_filter *cf, fz_obj *dict, char *name, int defaultlength);
/*
* Create crypt object for decrypting strings and streams
* given the Encryption and ID objects.
*/
fz_error
pdf_new_crypt(pdf_crypt **cryptp, fz_obj *dict, fz_obj *id)
{
pdf_crypt *crypt;
fz_error error;
fz_obj *obj;
crypt = fz_malloc(sizeof(pdf_crypt));
memset(crypt, 0x00, sizeof(pdf_crypt));
/* Common to all security handlers (PDF 1.7 table 3.18) */
obj = fz_dict_gets(dict, "Filter");
if (!fz_is_name(obj))
{
pdf_free_crypt(crypt);
return fz_throw("unspecified encryption handler");
}
if (strcmp(fz_to_name(obj), "Standard") != 0)
{
pdf_free_crypt(crypt);
return fz_throw("unknown encryption handler: '%s'", fz_to_name(obj));
}
crypt->v = 0;
obj = fz_dict_gets(dict, "V");
if (fz_is_int(obj))
crypt->v = fz_to_int(obj);
if (crypt->v != 1 && crypt->v != 2 && crypt->v != 4 && crypt->v != 5)
{
pdf_free_crypt(crypt);
return fz_throw("unknown encryption version");
}
crypt->length = 40;
if (crypt->v == 2 || crypt->v == 4)
{
obj = fz_dict_gets(dict, "Length");
if (fz_is_int(obj))
crypt->length = fz_to_int(obj);
/* work-around for pdf generators that assume length is in bytes */
if (crypt->length < 40)
crypt->length = crypt->length * 8;
if (crypt->length % 8 != 0)
{
pdf_free_crypt(crypt);
return fz_throw("invalid encryption key length");
}
if (crypt->length > 256)
{
pdf_free_crypt(crypt);
return fz_throw("invalid encryption key length");
}
}
if (crypt->v == 5)
crypt->length = 256;
if (crypt->v == 1 || crypt->v == 2)
{
crypt->stmf.method = PDF_CRYPT_RC4;
crypt->stmf.length = crypt->length;
crypt->strf.method = PDF_CRYPT_RC4;
crypt->strf.length = crypt->length;
}
if (crypt->v == 4 || crypt->v == 5)
{
crypt->stmf.method = PDF_CRYPT_NONE;
crypt->stmf.length = crypt->length;
crypt->strf.method = PDF_CRYPT_NONE;
crypt->strf.length = crypt->length;
obj = fz_dict_gets(dict, "CF");
if (fz_is_dict(obj))
{
crypt->cf = fz_keep_obj(obj);
}
else
{
crypt->cf = NULL;
}
obj = fz_dict_gets(dict, "StmF");
if (fz_is_name(obj))
{
error = pdf_parse_crypt_filter(&crypt->stmf, crypt->cf, fz_to_name(obj), crypt->length);
if (error)
{
pdf_free_crypt(crypt);
return fz_rethrow(error, "cannot parse stream crypt filter (%d %d R)", fz_to_num(obj), fz_to_gen(obj));
}
}
obj = fz_dict_gets(dict, "StrF");
if (fz_is_name(obj))
{
error = pdf_parse_crypt_filter(&crypt->strf, crypt->cf, fz_to_name(obj), crypt->length);
if (error)
{
pdf_free_crypt(crypt);
return fz_rethrow(error, "cannot parse string crypt filter (%d %d R)", fz_to_num(obj), fz_to_gen(obj));
}
}
/* in crypt revision 4, the crypt filter determines the key length */
if (crypt->strf.method != PDF_CRYPT_NONE)
crypt->length = crypt->stmf.length;
}
/* Standard security handler (PDF 1.7 table 3.19) */
obj = fz_dict_gets(dict, "R");
if (fz_is_int(obj))
crypt->r = fz_to_int(obj);
else
{
pdf_free_crypt(crypt);
return fz_throw("encryption dictionary missing revision value");
}
obj = fz_dict_gets(dict, "O");
if (fz_is_string(obj) && fz_to_str_len(obj) == 32)
memcpy(crypt->o, fz_to_str_buf(obj), 32);
/* /O and /U are supposed to be 48 bytes long for revision 5, they're often longer, though */
else if (crypt->r == 5 && fz_is_string(obj) && fz_to_str_len(obj) >= 48)
memcpy(crypt->o, fz_to_str_buf(obj), 48);
else
{
pdf_free_crypt(crypt);
return fz_throw("encryption dictionary missing owner password");
}
obj = fz_dict_gets(dict, "U");
if (fz_is_string(obj) && fz_to_str_len(obj) == 32)
memcpy(crypt->u, fz_to_str_buf(obj), 32);
else if (fz_is_string(obj) && fz_to_str_len(obj) >= 48 && crypt->r == 5)
memcpy(crypt->u, fz_to_str_buf(obj), 48);
else if (fz_is_string(obj) && fz_to_str_len(obj) < 32)
{
fz_warn("encryption password key too short (%d)", fz_to_str_len(obj));
memcpy(crypt->u, fz_to_str_buf(obj), fz_to_str_len(obj));
}
else
{
pdf_free_crypt(crypt);
return fz_throw("encryption dictionary missing user password");
}
obj = fz_dict_gets(dict, "P");
if (fz_is_int(obj))
crypt->p = fz_to_int(obj);
else
{
pdf_free_crypt(crypt);
return fz_throw("encryption dictionary missing permissions value");
}
if (crypt->r == 5)
{
obj = fz_dict_gets(dict, "OE");
if (!fz_is_string(obj) || fz_to_str_len(obj) != 32)
{
pdf_free_crypt(crypt);
return fz_throw("encryption dictionary missing owner encryption key");
}
memcpy(crypt->oe, fz_to_str_buf(obj), 32);
obj = fz_dict_gets(dict, "UE");
if (!fz_is_string(obj) || fz_to_str_len(obj) != 32)
{
pdf_free_crypt(crypt);
return fz_throw("encryption dictionary missing user encryption key");
}
memcpy(crypt->ue, fz_to_str_buf(obj), 32);
}
crypt->encrypt_metadata = 1;
obj = fz_dict_gets(dict, "EncryptMetadata");
if (fz_is_bool(obj))
crypt->encrypt_metadata = fz_to_bool(obj);
/* Extract file identifier string */
if (fz_is_array(id) && fz_array_len(id) == 2)
{
obj = fz_array_get(id, 0);
if (fz_is_string(obj))
crypt->id = fz_keep_obj(obj);
}
else
fz_warn("missing file identifier, may not be able to do decryption");
*cryptp = crypt;
return fz_okay;
}
void
pdf_free_crypt(pdf_crypt *crypt)
{
if (crypt->id) fz_drop_obj(crypt->id);
if (crypt->cf) fz_drop_obj(crypt->cf);
fz_free(crypt);
}
/*
* Parse a CF dictionary entry (PDF 1.7 table 3.22)
*/
static fz_error
pdf_parse_crypt_filter(pdf_crypt_filter *cf, fz_obj *cf_obj, char *name, int defaultlength)
{
fz_obj *obj;
fz_obj *dict;
int is_identity = (strcmp(name, "Identity") == 0);
int is_stdcf = (!is_identity && (strcmp(name, "StdCF") == 0));
if (!is_identity && !is_stdcf)
{
return fz_throw("Crypt Filter not Identity or StdCF (%d %d R)", fz_to_num(cf_obj), fz_to_gen(cf_obj));
}
cf->method = PDF_CRYPT_NONE;
cf->length = defaultlength;
if (cf_obj == NULL)
{
cf->method = (is_identity ? PDF_CRYPT_NONE : PDF_CRYPT_RC4);
return fz_okay;
}
dict = fz_dict_gets(cf_obj, name);
if (!fz_is_dict(dict))
{
return fz_throw("cannot parse crypt filter (%d %d R)", fz_to_num(cf_obj), fz_to_gen(cf_obj));
}
obj = fz_dict_gets(dict, "CFM");
if (fz_is_name(obj))
{
if (!strcmp(fz_to_name(obj), "None"))
cf->method = PDF_CRYPT_NONE;
else if (!strcmp(fz_to_name(obj), "V2"))
cf->method = PDF_CRYPT_RC4;
else if (!strcmp(fz_to_name(obj), "AESV2"))
cf->method = PDF_CRYPT_AESV2;
else if (!strcmp(fz_to_name(obj), "AESV3"))
cf->method = PDF_CRYPT_AESV3;
else
fz_throw("unknown encryption method: %s", fz_to_name(obj));
}
obj = fz_dict_gets(dict, "Length");
if (fz_is_int(obj))
cf->length = fz_to_int(obj);
/* the length for crypt filters is supposed to be in bytes not bits */
if (cf->length < 40)
cf->length = cf->length * 8;
if ((cf->length % 8) != 0)
return fz_throw("invalid key length: %d", cf->length);
return fz_okay;
}
/*
* Compute an encryption key (PDF 1.7 algorithm 3.2)
*/
static const unsigned char padding[32] =
{
0x28, 0xbf, 0x4e, 0x5e, 0x4e, 0x75, 0x8a, 0x41,
0x64, 0x00, 0x4e, 0x56, 0xff, 0xfa, 0x01, 0x08,
0x2e, 0x2e, 0x00, 0xb6, 0xd0, 0x68, 0x3e, 0x80,
0x2f, 0x0c, 0xa9, 0xfe, 0x64, 0x53, 0x69, 0x7a
};
static void
pdf_compute_encryption_key(pdf_crypt *crypt, unsigned char *password, int pwlen, unsigned char *key)
{
unsigned char buf[32];
unsigned int p;
int i, n;
fz_md5 md5;
n = crypt->length / 8;
/* Step 1 - copy and pad password string */
if (pwlen > 32)
pwlen = 32;
memcpy(buf, password, pwlen);
memcpy(buf + pwlen, padding, 32 - pwlen);
/* Step 2 - init md5 and pass value of step 1 */
fz_md5_init(&md5);
fz_md5_update(&md5, buf, 32);
/* Step 3 - pass O value */
fz_md5_update(&md5, crypt->o, 32);
/* Step 4 - pass P value as unsigned int, low-order byte first */
p = (unsigned int) crypt->p;
buf[0] = (p) & 0xFF;
buf[1] = (p >> 8) & 0xFF;
buf[2] = (p >> 16) & 0xFF;
buf[3] = (p >> 24) & 0xFF;
fz_md5_update(&md5, buf, 4);
/* Step 5 - pass first element of ID array */
fz_md5_update(&md5, (unsigned char *)fz_to_str_buf(crypt->id), fz_to_str_len(crypt->id));
/* Step 6 (revision 4 or greater) - if metadata is not encrypted pass 0xFFFFFFFF */
if (crypt->r >= 4)
{
if (!crypt->encrypt_metadata)
{
buf[0] = 0xFF;
buf[1] = 0xFF;
buf[2] = 0xFF;
buf[3] = 0xFF;
fz_md5_update(&md5, buf, 4);
}
}
/* Step 7 - finish the hash */
fz_md5_final(&md5, buf);
/* Step 8 (revision 3 or greater) - do some voodoo 50 times */
if (crypt->r >= 3)
{
for (i = 0; i < 50; i++)
{
fz_md5_init(&md5);
fz_md5_update(&md5, buf, n);
fz_md5_final(&md5, buf);
}
}
/* Step 9 - the key is the first 'n' bytes of the result */
memcpy(key, buf, n);
}
/*
* Compute an encryption key (PDF 1.7 ExtensionLevel 3 algorithm 3.2a)
*/
static void
pdf_compute_encryption_key_r5(pdf_crypt *crypt, unsigned char *password, int pwlen, int ownerkey, unsigned char *validationkey)
{
unsigned char buffer[128 + 8 + 48];
fz_sha256 sha256;
fz_aes aes;
/* Step 2 - truncate UTF-8 password to 127 characters */
if (pwlen > 127)
pwlen = 127;
/* Step 3/4 - test password against owner/user key and compute encryption key */
memcpy(buffer, password, pwlen);
if (ownerkey)
{
memcpy(buffer + pwlen, crypt->o + 32, 8);
memcpy(buffer + pwlen + 8, crypt->u, 48);
}
else
memcpy(buffer + pwlen, crypt->u + 32, 8);
fz_sha256_init(&sha256);
fz_sha256_update(&sha256, buffer, pwlen + 8 + (ownerkey ? 48 : 0));
fz_sha256_final(&sha256, validationkey);
/* Step 3.5/4.5 - compute file encryption key from OE/UE */
memcpy(buffer + pwlen, crypt->u + 40, 8);
fz_sha256_init(&sha256);
fz_sha256_update(&sha256, buffer, pwlen + 8);
fz_sha256_final(&sha256, buffer);
// clear password buffer and use it as iv
memset(buffer + 32, 0, sizeof(buffer) - 32);
aes_setkey_dec(&aes, buffer, crypt->length);
aes_crypt_cbc(&aes, AES_DECRYPT, 32, buffer + 32, ownerkey ? crypt->oe : crypt->ue, crypt->key);
}
/*
* Computing the user password (PDF 1.7 algorithm 3.4 and 3.5)
* Also save the generated key for decrypting objects and streams in crypt->key.
*/
static void
pdf_compute_user_password(pdf_crypt *crypt, unsigned char *password, int pwlen, unsigned char *output)
{
if (crypt->r == 2)
{
fz_arc4 arc4;
pdf_compute_encryption_key(crypt, password, pwlen, crypt->key);
fz_arc4_init(&arc4, crypt->key, crypt->length / 8);
fz_arc4_encrypt(&arc4, output, padding, 32);
}
if (crypt->r == 3 || crypt->r == 4)
{
unsigned char xor[32];
unsigned char digest[16];
fz_md5 md5;
fz_arc4 arc4;
int i, x, n;
n = crypt->length / 8;
pdf_compute_encryption_key(crypt, password, pwlen, crypt->key);
fz_md5_init(&md5);
fz_md5_update(&md5, padding, 32);
fz_md5_update(&md5, (unsigned char*)fz_to_str_buf(crypt->id), fz_to_str_len(crypt->id));
fz_md5_final(&md5, digest);
fz_arc4_init(&arc4, crypt->key, n);
fz_arc4_encrypt(&arc4, output, digest, 16);
for (x = 1; x <= 19; x++)
{
for (i = 0; i < n; i++)
xor[i] = crypt->key[i] ^ x;
fz_arc4_init(&arc4, xor, n);
fz_arc4_encrypt(&arc4, output, output, 16);
}
memcpy(output + 16, padding, 16);
}
if (crypt->r == 5)
{
pdf_compute_encryption_key_r5(crypt, password, pwlen, 0, output);
}
}
/*
* Authenticating the user password (PDF 1.7 algorithm 3.6
* and ExtensionLevel 3 algorithm 3.11)
* This also has the side effect of saving a key generated
* from the password for decrypting objects and streams.
*/
static int
pdf_authenticate_user_password(pdf_crypt *crypt, unsigned char *password, int pwlen)
{
unsigned char output[32];
pdf_compute_user_password(crypt, password, pwlen, output);
if (crypt->r == 2 || crypt->r == 5)
return memcmp(output, crypt->u, 32) == 0;
if (crypt->r == 3 || crypt->r == 4)
return memcmp(output, crypt->u, 16) == 0;
return 0;
}
/*
* Authenticating the owner password (PDF 1.7 algorithm 3.7
* and ExtensionLevel 3 algorithm 3.12)
* Generates the user password from the owner password
* and calls pdf_authenticate_user_password.
*/
static int
pdf_authenticate_owner_password(pdf_crypt *crypt, unsigned char *ownerpass, int pwlen)
{
unsigned char pwbuf[32];
unsigned char key[32];
unsigned char xor[32];
unsigned char userpass[32];
int i, n, x;
fz_md5 md5;
fz_arc4 arc4;
if (crypt->r == 5)
{
/* PDF 1.7 ExtensionLevel 3 algorithm 3.12 */
pdf_compute_encryption_key_r5(crypt, ownerpass, pwlen, 1, key);
return !memcmp(key, crypt->o, 32);
}
n = crypt->length / 8;
/* Step 1 -- steps 1 to 4 of PDF 1.7 algorithm 3.3 */
/* copy and pad password string */
if (pwlen > 32)
pwlen = 32;
memcpy(pwbuf, ownerpass, pwlen);
memcpy(pwbuf + pwlen, padding, 32 - pwlen);
/* take md5 hash of padded password */
fz_md5_init(&md5);
fz_md5_update(&md5, pwbuf, 32);
fz_md5_final(&md5, key);
/* do some voodoo 50 times (Revision 3 or greater) */
if (crypt->r >= 3)
{
for (i = 0; i < 50; i++)
{
fz_md5_init(&md5);
fz_md5_update(&md5, key, 16);
fz_md5_final(&md5, key);
}
}
/* Step 2 (Revision 2) */
if (crypt->r == 2)
{
fz_arc4_init(&arc4, key, n);
fz_arc4_encrypt(&arc4, userpass, crypt->o, 32);
}
/* Step 2 (Revision 3 or greater) */
if (crypt->r >= 3)
{
memcpy(userpass, crypt->o, 32);
for (x = 0; x < 20; x++)
{
for (i = 0; i < n; i++)
xor[i] = key[i] ^ (19 - x);
fz_arc4_init(&arc4, xor, n);
fz_arc4_encrypt(&arc4, userpass, userpass, 32);
}
}
return pdf_authenticate_user_password(crypt, userpass, 32);
}
int
pdf_authenticate_password(pdf_xref *xref, char *password)
{
if (xref->crypt)
{
if (pdf_authenticate_user_password(xref->crypt, (unsigned char *)password, strlen(password)))
return 1;
if (pdf_authenticate_owner_password(xref->crypt, (unsigned char *)password, strlen(password)))
return 1;
return 0;
}
return 1;
}
int
pdf_needs_password(pdf_xref *xref)
{
if (!xref->crypt)
return 0;
if (pdf_authenticate_password(xref, ""))
return 0;
return 1;
}
int
pdf_has_permission(pdf_xref *xref, int p)
{
if (!xref->crypt)
return 1;
return xref->crypt->p & p;
}
unsigned char *
pdf_get_crypt_key(pdf_xref *xref)
{
if (xref->crypt)
return xref->crypt->key;
return NULL;
}
int
pdf_get_crypt_revision(pdf_xref *xref)
{
if (xref->crypt)
return xref->crypt->v;
return 0;
}
char *
pdf_get_crypt_method(pdf_xref *xref)
{
if (xref->crypt)
{
switch (xref->crypt->strf.method)
{
case PDF_CRYPT_NONE: return "None";
case PDF_CRYPT_RC4: return "RC4";
case PDF_CRYPT_AESV2: return "AES";
case PDF_CRYPT_AESV3: return "AES";
case PDF_CRYPT_UNKNOWN: return "Unknown";
}
}
return "None";
}
int
pdf_get_crypt_length(pdf_xref *xref)
{
if (xref->crypt)
return xref->crypt->length;
return 0;
}
/*
* PDF 1.7 algorithm 3.1 and ExtensionLevel 3 algorithm 3.1a
*
* Using the global encryption key that was generated from the
* password, create a new key that is used to decrypt indivual
* objects and streams. This key is based on the object and
* generation numbers.
*/
static int
pdf_compute_object_key(pdf_crypt *crypt, pdf_crypt_filter *cf, int num, int gen, unsigned char *key)
{
fz_md5 md5;
unsigned char message[5];
if (cf->method == PDF_CRYPT_AESV3)
{
memcpy(key, crypt->key, crypt->length / 8);
return crypt->length / 8;
}
fz_md5_init(&md5);
fz_md5_update(&md5, crypt->key, crypt->length / 8);
message[0] = (num) & 0xFF;
message[1] = (num >> 8) & 0xFF;
message[2] = (num >> 16) & 0xFF;
message[3] = (gen) & 0xFF;
message[4] = (gen >> 8) & 0xFF;
fz_md5_update(&md5, message, 5);
if (cf->method == PDF_CRYPT_AESV2)
fz_md5_update(&md5, (unsigned char *)"sAlT", 4);
fz_md5_final(&md5, key);
if (crypt->length / 8 + 5 > 16)
return 16;
return crypt->length / 8 + 5;
}
/*
* PDF 1.7 algorithm 3.1 and ExtensionLevel 3 algorithm 3.1a
*
* Decrypt all strings in obj modifying the data in-place.
* Recurse through arrays and dictionaries, but do not follow
* indirect references.
*/
static void
pdf_crypt_obj_imp(pdf_crypt *crypt, fz_obj *obj, unsigned char *key, int keylen)
{
unsigned char *s;
int i, n;
if (fz_is_indirect(obj))
return;
if (fz_is_string(obj))
{
s = (unsigned char *) fz_to_str_buf(obj);
n = fz_to_str_len(obj);
if (crypt->strf.method == PDF_CRYPT_RC4)
{
fz_arc4 arc4;
fz_arc4_init(&arc4, key, keylen);
fz_arc4_encrypt(&arc4, s, s, n);
}
if (crypt->strf.method == PDF_CRYPT_AESV2 || crypt->strf.method == PDF_CRYPT_AESV3)
{
if (n & 15 || n < 32)
fz_warn("invalid string length for aes encryption");
else
{
unsigned char iv[16];
fz_aes aes;
memcpy(iv, s, 16);
aes_setkey_dec(&aes, key, keylen * 8);
aes_crypt_cbc(&aes, AES_DECRYPT, n - 16, iv, s + 16, s);
/* delete space used for iv and padding bytes at end */
if (s[n - 17] < 1 || s[n - 17] > 16)
fz_warn("aes padding out of range");
else
fz_set_str_len(obj, n - 16 - s[n - 17]);
}
}
}
else if (fz_is_array(obj))
{
n = fz_array_len(obj);
for (i = 0; i < n; i++)
{
pdf_crypt_obj_imp(crypt, fz_array_get(obj, i), key, keylen);
}
}
else if (fz_is_dict(obj))
{
n = fz_dict_len(obj);
for (i = 0; i < n; i++)
{
pdf_crypt_obj_imp(crypt, fz_dict_get_val(obj, i), key, keylen);
}
}
}
void
pdf_crypt_obj(pdf_crypt *crypt, fz_obj *obj, int num, int gen)
{
unsigned char key[32];
int len;
len = pdf_compute_object_key(crypt, &crypt->strf, num, gen, key);
pdf_crypt_obj_imp(crypt, obj, key, len);
}
/*
* PDF 1.7 algorithm 3.1 and ExtensionLevel 3 algorithm 3.1a
*
* Create filter suitable for de/encrypting a stream.
*/
static fz_stream *
pdf_open_crypt_imp(fz_stream *chain, pdf_crypt *crypt, pdf_crypt_filter *stmf, int num, int gen)
{
unsigned char key[32];
int len;
len = pdf_compute_object_key(crypt, stmf, num, gen, key);
if (stmf->method == PDF_CRYPT_RC4)
return fz_open_arc4(chain, key, len);
if (stmf->method == PDF_CRYPT_AESV2 || stmf->method == PDF_CRYPT_AESV3)
return fz_open_aesd(chain, key, len);
return fz_open_copy(chain);
}
fz_stream *
pdf_open_crypt(fz_stream *chain, pdf_crypt *crypt, int num, int gen)
{
return pdf_open_crypt_imp(chain, crypt, &crypt->stmf, num, gen);
}
fz_stream *
pdf_open_crypt_with_filter(fz_stream *chain, pdf_crypt *crypt, char *name, int num, int gen)
{
fz_error error;
pdf_crypt_filter cf;
if (strcmp(name, "Identity"))
{
error = pdf_parse_crypt_filter(&cf, crypt->cf, name, crypt->length);
if (error)
fz_catch(error, "cannot parse crypt filter (%d %d R)", num, gen);
else
return pdf_open_crypt_imp(chain, crypt, &cf, num, gen);
}
return chain;
}
void pdf_debug_crypt(pdf_crypt *crypt)
{
int i;
printf("crypt {\n");
printf("\tv=%d length=%d\n", crypt->v, crypt->length);
printf("\tstmf method=%d length=%d\n", crypt->stmf.method, crypt->stmf.length);
printf("\tstrf method=%d length=%d\n", crypt->strf.method, crypt->strf.length);
printf("\tr=%d\n", crypt->r);
printf("\to=<");
for (i = 0; i < 32; i++)
printf("%02X", crypt->o[i]);
printf(">\n");
printf("\tu=<");
for (i = 0; i < 32; i++)
printf("%02X", crypt->u[i]);
printf(">\n");
printf("}\n");
}
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