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-rw-r--r--Build/source/texk/dvipdf-x/xsrc/pdfencrypt.c539
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diff --git a/Build/source/texk/dvipdf-x/xsrc/pdfencrypt.c b/Build/source/texk/dvipdf-x/xsrc/pdfencrypt.c
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+++ /dev/null
@@ -1,539 +0,0 @@
-/*
-
- This is dvipdfmx, an eXtended version of dvipdfm by Mark A. Wicks.
-
- Copyright (C) 2002-2012 by Jin-Hwan Cho and Shunsaku Hirata,
- the dvipdfmx project team.
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
-*/
-
-#if HAVE_CONFIG_H
-#include "config.h"
-#endif
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <time.h>
-
-#ifdef WIN32
-#include <conio.h>
-#define getch _getch
-#else /* !WIN32 */
-#include <unistd.h>
-#endif /* WIN32 */
-
-#include "system.h"
-#include "mem.h"
-#include "error.h"
-#include "pdfobj.h"
-#include "dpxcrypt.h"
-
-#include "pdfencrypt.h"
-
-#define MAX_KEY_LEN 16
-#define MAX_STR_LEN 32
-
-static unsigned char algorithm, revision, key_size;
-static unsigned long permission;
-
-static unsigned char key_data[MAX_KEY_LEN], id_string[MAX_KEY_LEN];
-static unsigned char opwd_string[MAX_STR_LEN], upwd_string[MAX_STR_LEN];
-
-static unsigned long current_label = 0;
-static unsigned current_generation = 0;
-
-static ARC4_KEY key;
-static MD5_CONTEXT md5_ctx;
-
-static unsigned char md5_buf[MAX_KEY_LEN], key_buf[MAX_KEY_LEN];
-static unsigned char in_buf[MAX_STR_LEN], out_buf[MAX_STR_LEN];
-
-static const unsigned char padding_string[MAX_STR_LEN] = {
- 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 char owner_passwd[MAX_PWD_LEN], user_passwd[MAX_PWD_LEN];
-
-static unsigned char verbose = 0;
-
-void pdf_enc_set_verbose (void)
-{
- if (verbose < 255) verbose++;
-}
-
-#define PRODUCER "%s-%s, Copyright \251 2002-2010 by Jin-Hwan Cho, Matthias Franz, and Shunsaku Hirata"
-void pdf_enc_compute_id_string (char *dviname, char *pdfname)
-{
- char *date_string, *producer;
- time_t current_time;
- struct tm *bd_time;
-
- MD5_init(&md5_ctx);
-
- date_string = NEW (15, char);
- time(&current_time);
- bd_time = localtime(&current_time);
- sprintf (date_string, "%04d%02d%02d%02d%02d%02d",
- bd_time -> tm_year+1900, bd_time -> tm_mon+1, bd_time -> tm_mday,
- bd_time -> tm_hour, bd_time -> tm_min, bd_time -> tm_sec);
- MD5_write(&md5_ctx, (unsigned char *)date_string, strlen(date_string));
- RELEASE (date_string);
-
- producer = NEW (strlen(PRODUCER)+strlen("xdvipdfmx")+strlen(VERSION), char);
- sprintf(producer, PRODUCER, "xdvipdfmx", VERSION);
- MD5_write(&md5_ctx, (unsigned char *)producer, strlen(producer));
- RELEASE (producer);
-
- if (dviname)
- MD5_write(&md5_ctx, (unsigned char *)dviname, strlen(dviname));
- if (pdfname)
- MD5_write(&md5_ctx, (unsigned char *)pdfname, strlen(pdfname));
- MD5_final(id_string, &md5_ctx);
-}
-
-static void passwd_padding (unsigned char *src, unsigned char *dst)
-{
- register int len = strlen((char *)src);
-
- if (len > MAX_STR_LEN)
- len = MAX_STR_LEN;
-
- memcpy(dst, src, len);
- memcpy(dst+len, padding_string, MAX_STR_LEN-len);
-}
-
-static void compute_owner_password (void)
-{
- register unsigned char i, j;
- /*
- * Algorithm 3.3 Computing the encryption dictionary's O (owner password)
- * value
- *
- * 1. Pad or truncate the owner password string as described in step 1
- * of Algorithm 3.2. If there is no owner password, use the user
- * password instead. (See implementation note 17 in Appendix H.)
- */
- passwd_padding((unsigned char *)(strlen(owner_passwd) > 0 ? owner_passwd : user_passwd), in_buf);
- /*
- * 2. Initialize the MD5 hash function and pass the result of step 1
- * as input to this function.
- */
- MD5_init(&md5_ctx);
- MD5_write(&md5_ctx, in_buf, MAX_STR_LEN);
- MD5_final(md5_buf, &md5_ctx);
- /*
- * 3. (Revision 3 only) Do the following 50 times: Take the output
- * from the previous MD5 hash and pass it as input into a new
- * MD5 hash.
- */
- if (revision == 3)
- for (i = 0; i < 50; i++) {
- /*
- * NOTE: We truncate each MD5 hash as in the following step.
- * Otherwise Adobe Reader won't decrypt the PDF file.
- */
- MD5_init(&md5_ctx);
- MD5_write(&md5_ctx, md5_buf, key_size);
- MD5_final(md5_buf, &md5_ctx);
- }
- /*
- * 4. Create an RC4 encryption key using the first n bytes of the output
- * from the final MD5 hash, where n is always 5 for revision 2 but
- * for revision 3 depends on the value of the encryption dictionary's
- * Length entry.
- */
- ARC4_set_key(&key, key_size, md5_buf);
- /*
- * 5. Pad or truncate the user password string as described in step 1
- * of Algorithm 3.2.
- */
- passwd_padding((unsigned char *)user_passwd, in_buf);
- /*
- * 6. Encrypt the result of step 5, using an RC4 encryption function
- * with the encryption key obtained in step 4.
- */
- ARC4(&key, MAX_STR_LEN, in_buf, out_buf);
- /*
- * 7. (Revision 3 only) Do the following 19 times: Take the output
- * from the previous invocation of the RC4 function and pass it
- * as input to a new invocation of the function; use an encryption
- * key generated by taking each byte of the encryption key obtained
- * in step 4 and performing an XOR (exclusive or) operation between
- * that byte and the single-byte value of the iteration counter
- * (from 1 to 19).
- */
- if (revision == 3)
- for (i = 1; i <= 19; i++) {
- memcpy(in_buf, out_buf, MAX_STR_LEN);
- for (j = 0; j < key_size; j++)
- key_buf[j] = md5_buf[j] ^ i;
- ARC4_set_key(&key, key_size, key_buf);
- ARC4(&key, MAX_STR_LEN, in_buf, out_buf);
- }
- /*
- * 8. Store the output from the final invocation of the RC4 function
- * as the value of the O entry in the encryption dictionary.
- */
- memcpy(opwd_string, out_buf, MAX_STR_LEN);
-}
-
-static void compute_encryption_key (unsigned char *pwd)
-{
- register unsigned char i;
- /*
- * Algorithm 3.2 Computing an encryption key
- *
- * 1. Pad or truncate the password string to exactly 32 bytes. If the
- * password string is more than 32 bytes long, use only its first
- * 32 bytes; if it is less than 32 bytes long, pad it by appending
- * the required number of additional bytes from the beginning of
- * the following padding string:
- *
- * < 28 BF 4E 5E 4E 75 8A 41 64 00 4E 56 FF FA 01 08
- * 2E 2E 00 B6 D0 68 3E 80 2F 0C A9 FE 64 53 69 7A >
- *
- * That is, if the password string is n bytes long, append the
- * first 32 - n bytes of the padding string to the end of the
- * password string. If the password string is empty (zero-length),
- * meaning there is no user password, substitute the entire
- * padding string in its place.
- */
- passwd_padding(pwd, in_buf);
- /*
- * 2. Initialize the MD5 hash function and pass the result of step 1
- * as input to this fuction.
- */
- MD5_init(&md5_ctx);
- MD5_write(&md5_ctx, in_buf, MAX_STR_LEN);
- /*
- * 3. Pass the value of the encryption dictionary's O entry to the
- * MD5 hash function. (Algorithm 3.3 shows how the O value is
- * computed.)
- */
- MD5_write(&md5_ctx, opwd_string, MAX_STR_LEN);
- /*
- * 4. Treat the value of the P entry as an unsigned 4-byte integer
- * and pass these bytes to the MD5 hash function, low-order byte
- * first.
- */
- in_buf[0] = (unsigned char)(permission) & 0xFF;
- in_buf[1] = (unsigned char)(permission >> 8) & 0xFF;
- in_buf[2] = (unsigned char)(permission >> 16) & 0xFF;
- in_buf[3] = (unsigned char)(permission >> 24) & 0xFF;
- MD5_write(&md5_ctx, in_buf, 4);
- /*
- * 5. Pass the first element of the file's file identifier array
- * (the value of the ID entry in the document's trailer dictionary;
- * see Table 3.12 on page 68) to the MD5 hash function and
- * finish the hash.
- */
- MD5_write(&md5_ctx, id_string, MAX_KEY_LEN);
- MD5_final(md5_buf, &md5_ctx);
- /*
- * 6. (Revision 3 only) Do the following 50 times; Take the output from
- * the previous MD5 hash and pass it as input into a new MD5 hash.
- */
- if (revision == 3)
- for (i = 0; i < 50; i++) {
- /*
- * NOTE: We truncate each MD5 hash as in the following step.
- * Otherwise Adobe Reader won't decrypt the PDF file.
- */
- MD5_init(&md5_ctx);
- MD5_write(&md5_ctx, md5_buf, key_size);
- MD5_final(md5_buf, &md5_ctx);
- }
- /*
- * 7. Set the encryption key to the first n bytes of the output from
- * the final MD5 hash, where n is always 5 for revision 2 but for
- * revision 3 depends on the value of the encryption dictionary's
- * Length entry.
- */
- memcpy(key_data, md5_buf, key_size);
-}
-
-static void compute_user_password (void)
-{
- register unsigned char i, j;
- /*
- * Algorithm 3.4 Computing the encryption dictionary's U (user password)
- * value (Revision 2)
- *
- * 1. Create an encryption key based on the user password string, as
- * described in Algorithm 3.2.
- *
- * 2. Encrypt the 32-byte padding string shown in step 1 of Algorithm
- * 3.2, using an RC4 encryption fuction with the encryption key from
- * the preceeding step.
- *
- * 3. Store the result of step 2 as the value of the U entry in the
- * encryption dictionary.
- */
- /*
- * Algorithm 3.5 Computing the encryption dictionary's U (user password)
- * value (Revision 3)
- *
- * 1. Create an encryption key based on the user password string, as
- * described in Algorithm 3.2.
- *
- * 2. Initialize the MD5 hash function and pass the 32-byte padding
- * string shown in step 1 of Algorithm 3.2 as input to this function.
- *
- * 3. Pass the first element of the file's file identifier array (the
- * value of the ID entry in the document's trailer dictionary; see
- * Table 3.12 on page 68) to the hash function and finish the hash.
- *
- * 4. Encrypt the 16-byte result of the hash, using an RC4 encryption
- * function with the encryption key from step 1.
- *
- * 5. Do the following 19 times: Take the output from the previous
- * invocation of the RC4 function and pass it as input to a new
- * invocation of the function; use an encryption key generated by
- * taking each byte of the original encryption key (obtained in
- * step 1) and performing an XOR (exclusive or) operation between
- * that byte and the single-byte value of the iteration counter
- * (from 1 to 19).
- *
- * 6. Append 16 bytes of arbitrary padding to the output from the
- * final invocation of the RC4 function and store the 32-byte
- * result as the value of the U entry in the encryption dictionary.
- */
- compute_encryption_key((unsigned char *)user_passwd);
-
- switch (revision) {
- case 2:
- ARC4_set_key(&key, key_size, key_data);
- ARC4(&key, MAX_STR_LEN, padding_string, out_buf);
- break;
- case 3:
- MD5_init(&md5_ctx);
- MD5_write(&md5_ctx, padding_string, MAX_STR_LEN);
-
- MD5_write(&md5_ctx, id_string, MAX_KEY_LEN);
- MD5_final(md5_buf, &md5_ctx);
-
- ARC4_set_key(&key, key_size, key_data);
- ARC4(&key, MAX_KEY_LEN, md5_buf, out_buf);
-
- for (i = 1; i <= 19; i++) {
- memcpy(in_buf, out_buf, MAX_KEY_LEN);
- for (j = 0; j < key_size; j++)
- key_buf[j] = key_data[j] ^ i;
- ARC4_set_key(&key, key_size, key_buf);
- ARC4(&key, MAX_KEY_LEN, in_buf, out_buf);
- }
- break;
- default:
- ERROR("Invalid revision number.\n");
- }
-
- memcpy(upwd_string, out_buf, MAX_STR_LEN);
-}
-
-#ifdef WIN32
-static char *getpass (const char *prompt)
-{
- static char pwd_buf[128];
- size_t i;
-
- fputs(prompt, stderr);
- fflush(stderr);
- for (i = 0; i < sizeof(pwd_buf)-1; i++) {
- pwd_buf[i] = getch();
- if (pwd_buf[i] == '\r')
- break;
- fputs("*", stderr);
- fflush(stderr);
- }
- pwd_buf[i] = '\0';
- fputs("\n", stderr);
- return pwd_buf;
-}
-#endif
-
-void pdf_enc_set_passwd (unsigned bits, unsigned perm, const char *owner_pw, const char *user_pw)
-{
- char *retry_passwd;
-
- if (owner_pw) {
- strncpy(owner_passwd, owner_pw, MAX_PWD_LEN);
- } else
- while (1) {
- strncpy(owner_passwd, getpass("Owner password: "), MAX_PWD_LEN);
- retry_passwd = getpass("Re-enter owner password: ");
- if (!strncmp(owner_passwd, retry_passwd, MAX_PWD_LEN))
- break;
- fputs("Password is not identical.\nTry again.\n", stderr);
- fflush(stderr);
- }
-
- if (user_pw) {
- strncpy(user_passwd, user_pw, MAX_PWD_LEN);
- } else
- while (1) {
- strncpy(user_passwd, getpass("User password: "), MAX_PWD_LEN);
- retry_passwd = getpass("Re-enter user password: ");
- if (!strncmp(user_passwd, retry_passwd, MAX_PWD_LEN))
- break;
- fputs("Password is not identical.\nTry again.\n", stderr);
- fflush(stderr);
- }
-
- key_size = (unsigned char)(bits / 8);
- algorithm = (key_size == 5 ? 1 : 2);
- permission = (unsigned long)perm | 0x000000C0;
- revision = ((algorithm == 1 && permission < 0x100) ? 2 : 3);
- if (revision == 3)
- permission |= 0xFFFFF000;
-
- compute_owner_password();
- compute_user_password();
-}
-
-void pdf_encrypt_data (unsigned char *data, unsigned long len)
-{
- unsigned char *result;
-
- memcpy(in_buf, key_data, key_size);
- in_buf[key_size] = (unsigned char)(current_label) & 0xFF;
- in_buf[key_size+1] = (unsigned char)(current_label >> 8) & 0xFF;
- in_buf[key_size+2] = (unsigned char)(current_label >> 16) & 0xFF;
- in_buf[key_size+3] = (unsigned char)(current_generation) & 0xFF;
- in_buf[key_size+4] = (unsigned char)(current_generation >> 8) & 0xFF;
-
- MD5_init(&md5_ctx);
- MD5_write(&md5_ctx, in_buf, key_size+5);
- MD5_final(md5_buf, &md5_ctx);
-
- result = NEW (len, unsigned char);
- ARC4_set_key(&key, (key_size > 10 ? MAX_KEY_LEN : key_size+5), md5_buf);
- ARC4(&key, len, data, result);
- memcpy(data, result, len);
- RELEASE (result);
-}
-
-pdf_obj *pdf_encrypt_obj (void)
-{
- pdf_obj *doc_encrypt;
-
-#ifdef DEBUG
- fprintf (stderr, "(pdf_encrypt_obj)");
-#endif
-
- doc_encrypt = pdf_new_dict ();
-
- /* KEY : Filter
- * TYPE : name
- * VALUE: (Required) The name of the security handler for this document;
- * see below. Default value: Standard, for the built-in security
- * handler.
- */
- pdf_add_dict (doc_encrypt,
- pdf_new_name ("Filter"),
- pdf_new_name ("Standard"));
- /* KEY : V
- * TYPE : number
- * VALUE: (Optional but strongly recommended) A code specifying the
- * algorithm to be used in encrypting and decrypting the document:
- * 0 An algorithm that is undocumented and no longer supported,
- * and whose use is strongly discouraged.
- * 1 Algorithm 3.1 on page 73, with an encryption key length
- * of 40 bits; see below.
- * 2 (PDF 1.4) Algorithm 3.1 on page 73, but allowing encryption
- * key lengths greater than 40 bits.
- * 3 (PDF 1.4) An unpublished algorithm allowing encryption key
- * lengths ranging from 40 to 128 bits. (This algorithm is
- * unpublished as an export requirement of the U.S. Department
- * of Commerce.)
- * The default value if this entry is omitted is 0, but a value
- * of 1 or greater is strongly recommended.
- */
- pdf_add_dict (doc_encrypt,
- pdf_new_name ("V"),
- pdf_new_number (algorithm));
- /* KEY : Length
- * TYPE : integer
- * VALUE: (Optional; PDF 1.4; only if V is 2 or 3) The length of the
- * encryption key, in bits. The value must be a multiple of 8,
- * in the range 40 to 128. Default value: 40.
- */
- if (algorithm > 1)
- pdf_add_dict (doc_encrypt,
- pdf_new_name ("Length"),
- pdf_new_number (key_size * 8));
- /* KEY : R
- * TYPE : number
- * VALUE: (Required) A number specifying which revision of the standard
- * security handler should be used to interpret this dictionary.
- * The revison number should be 2 if the document is encrypted
- * with a V value less than 2; otherwise this value should be 3.
- */
- pdf_add_dict (doc_encrypt,
- pdf_new_name ("R"),
- pdf_new_number (revision));
- /* KEY : O
- * TYPE : string
- * VALUE: (Required) A 32-byte string, based on both the owner and
- * user passwords, that is used in computing the encryption
- * key and in determining whether a valid owner password was
- * entered.
- */
- pdf_add_dict (doc_encrypt,
- pdf_new_name ("O"),
- pdf_new_string (opwd_string, 32));
- /* KEY : U
- * TYPE : string
- * VALUE: (Required) A 32-byte string, based on the user password,
- * that is used in determining whether to prompt the user
- * for a password and, if so, whether a valid user or owner
- * password was entered.
- */
- pdf_add_dict (doc_encrypt,
- pdf_new_name ("U"),
- pdf_new_string (upwd_string, 32));
- /* KEY : P
- * TYPE : integer
- * VALUE: (Required) A set of flags specifying which operations are
- * permitted when the document is opened with user access.
- */
- pdf_add_dict (doc_encrypt,
- pdf_new_name ("P"),
- pdf_new_number (permission));
-
- return doc_encrypt;
-}
-
-pdf_obj *pdf_enc_id_array (void)
-{
- pdf_obj *id = pdf_new_array();
- pdf_add_array(id, pdf_new_string(id_string, MAX_KEY_LEN));
- pdf_add_array(id, pdf_new_string(id_string, MAX_KEY_LEN));
- return id;
-}
-
-void pdf_enc_set_label (unsigned long label)
-{
- current_label = label;
-}
-
-void pdf_enc_set_generation (unsigned generation)
-{
- current_generation = generation;
-}