HPDF_GetInfoAttr (HPDF_Doc pdf,
HPDF_InfoType type)
{
const char *ret = NULL;
HPDF_Dict info = GetInfo (pdf);
HPDF_PTRACE((" HPDF_GetInfoAttr\n"));
if (info)
ret = HPDF_Info_GetInfoAttr (info, type);
else
HPDF_CheckError (&pdf->error);
return ret;
}
void
HPDF_EncryptDict_CreateID (HPDF_EncryptDict dict,
HPDF_Dict info,
HPDF_Xref xref)
{
HPDF_MD5_CTX ctx;
HPDF_Encrypt attr = (HPDF_Encrypt)dict->attr;
/* use the result of 'time' function to get random value.
* when debugging, 'time' value is ignored.
*/
#ifndef HPDF_DEBUG
time_t t = HPDF_TIME (NULL);
#endif /* HPDF_DEBUG */
HPDF_MD5Init (&ctx);
#ifndef HPDF_DEBUG
HPDF_MD5Update(&ctx, (HPDF_BYTE *)&t, sizeof(t));
/* create File Identifier from elements of Into dictionary. */
if (info) {
const char *s;
HPDF_UINT len;
/* Author */
s = HPDF_Info_GetInfoAttr (info, HPDF_INFO_AUTHOR);
if ((len = HPDF_StrLen (s, -1)) > 0)
HPDF_MD5Update(&ctx, (const HPDF_BYTE *)s, len);
/* Creator */
s = HPDF_Info_GetInfoAttr (info, HPDF_INFO_CREATOR);
if ((len = HPDF_StrLen (s, -1)) > 0)
HPDF_MD5Update(&ctx, (const HPDF_BYTE *)s, len);
/* Producer */
s = HPDF_Info_GetInfoAttr (info, HPDF_INFO_PRODUCER);
if ((len = HPDF_StrLen (s, -1)) > 0)
HPDF_MD5Update(&ctx, (const HPDF_BYTE *)s, len);
/* Title */
s = HPDF_Info_GetInfoAttr (info, HPDF_INFO_TITLE);
if ((len = HPDF_StrLen (s, -1)) > 0)
HPDF_MD5Update(&ctx, (const HPDF_BYTE *)s, len);
/* Subject */
s = HPDF_Info_GetInfoAttr (info, HPDF_INFO_SUBJECT);
if ((len = HPDF_StrLen (s, -1)) > 0)
HPDF_MD5Update(&ctx, (const HPDF_BYTE *)s, len);
/* Keywords */
s = HPDF_Info_GetInfoAttr (info, HPDF_INFO_KEYWORDS);
if ((len = HPDF_StrLen (s, -1)) > 0)
HPDF_MD5Update(&ctx, (const HPDF_BYTE *)s, len);
HPDF_MD5Update(&ctx, (const HPDF_BYTE *)&(xref->entries->count),
sizeof(HPDF_UINT32));
}
#endif
HPDF_MD5Final(attr->encrypt_id, &ctx);
}
