OpenSystemsDevelopment / qpdf

Commit 4635a59e65c859b5aac7b08f5780c6f0a679b948

Authored by m-holger
1 parent 11266b14

Remove redundant `compute_U_UE_value_V5`, `compute_O_OE_value_V5`, and `compute_… 

…Perms_value_V5` methods; inline their logic into `setV5EncryptionParameters` to simplify encryption data processing.
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Showing 2 changed files with 14 additions and 53 deletions
include/qpdf/QPDF.hh
  View file @4635a59
@@ -532,21 +532,9 @@ class QPDF @@ -532,21 +532,9 @@ class QPDF
532 532
533 std::string hash_V5( 533 std::string hash_V5(
534 std::string const& password, std::string const& salt, std::string const& udata) const; 534 std::string const& password, std::string const& salt, std::string const& udata) const;
535 - std::string compute_Perms_value_V5(std::string const& encryption_key) const;  
536 std::string 535 std::string
537 compute_O_value(std::string const& user_password, std::string const& owner_password) const; 536 compute_O_value(std::string const& user_password, std::string const& owner_password) const;
538 std::string compute_U_value(std::string const& user_password) const; 537 std::string compute_U_value(std::string const& user_password) const;
539 - void compute_O_OE_value_V5(  
540 - std::string const& owner_password,  
541 - std::string const& encryption_key,  
542 - std::string const& U,  
543 - std::string& O,  
544 - std::string& OE) const;  
545 - void compute_U_UE_value_V5(  
546 - std::string const& user_password,  
547 - std::string const& encryption_key,  
548 - std::string& U,  
549 - std::string& UE) const;  
550 std::string compute_encryption_key_from_password(std::string const& password) const; 538 std::string compute_encryption_key_from_password(std::string const& password) const;
551 std::string recover_encryption_key_with_password(std::string const& password) const; 539 std::string recover_encryption_key_with_password(std::string const& password) const;
552 bool check_owner_password_V4( 540 bool check_owner_password_V4(
libqpdf/QPDF_encryption.cc
  View file @4635a59
@@ -612,37 +612,6 @@ QPDF::EncryptionData::recover_encryption_key_with_password(std::string const& pa @@ -612,37 +612,6 @@ QPDF::EncryptionData::recover_encryption_key_with_password(std::string const& pa
612 return recover_encryption_key_with_password(password, disregard); 612 return recover_encryption_key_with_password(password, disregard);
613 } 613 }
614 614
615 -void  
616 -QPDF::EncryptionData::compute_U_UE_value_V5(  
617 - std::string const& user_password,  
618 - std::string const& encryption_key,  
619 - std::string& out_U,  
620 - std::string& out_UE) const  
621 -{  
622 - // Algorithm 3.8 from the PDF 1.7 extension level 3  
623 - auto validation_salt = util::random_string(8);  
624 - auto key_salt = util::random_string(8);  
625 - out_U = hash_V5(user_password, validation_salt, "").append(validation_salt).append(key_salt);  
626 - auto intermediate_key = hash_V5(user_password, key_salt, "");  
627 - out_UE = process_with_aes(intermediate_key, true, encryption_key);  
628 -}  
629 -  
630 -void  
631 -QPDF::EncryptionData::compute_O_OE_value_V5(  
632 - std::string const& owner_password,  
633 - std::string const& encryption_key,  
634 - std::string const& in_U,  
635 - std::string& out_O,  
636 - std::string& out_OE) const  
637 -{  
638 - // Algorithm 3.9 from the PDF 1.7 extension level 3  
639 - auto validation_salt = util::random_string(8);  
640 - auto key_salt = util::random_string(8);  
641 - out_O = hash_V5(owner_password, validation_salt, in_U) + validation_salt + key_salt;  
642 - std::string intermediate_key = hash_V5(owner_password, key_salt, in_U);  
643 - out_OE = process_with_aes(intermediate_key, true, encryption_key);  
644 -}  
645 -  
646 std::string 615 std::string
647 QPDF::EncryptionData::compute_Perms_value_V5_clear() const 616 QPDF::EncryptionData::compute_Perms_value_V5_clear() const
648 { 617 {
@@ -661,13 +630,6 @@ QPDF::EncryptionData::compute_Perms_value_V5_clear() const @@ -661,13 +630,6 @@ QPDF::EncryptionData::compute_Perms_value_V5_clear() const
661 } 630 }
662 631
663 std::string 632 std::string
664 -QPDF::EncryptionData::compute_Perms_value_V5(std::string const& encryption_key) const  
665 -{  
666 - // Algorithm 3.10 from the PDF 1.7 extension level 3  
667 - return process_with_aes(encryption_key, true, compute_Perms_value_V5_clear());  
668 -}  
669 -  
670 -std::string  
671 QPDF::EncryptionData::recover_encryption_key_with_password( 633 QPDF::EncryptionData::recover_encryption_key_with_password(
672 std::string const& password, bool& perms_valid) const 634 std::string const& password, bool& perms_valid) const
673 { 635 {
@@ -1207,9 +1169,20 @@ QPDF::EncryptionData::compute_encryption_parameters_V5( @@ -1207,9 +1169,20 @@ QPDF::EncryptionData::compute_encryption_parameters_V5(
1207 std::string& out_Perms) 1169 std::string& out_Perms)
1208 { 1170 {
1209 out_encryption_key = util::random_string(key_bytes); 1171 out_encryption_key = util::random_string(key_bytes);
1210 - compute_U_UE_value_V5(user_password, out_encryption_key, out_U, out_UE);  
1211 - compute_O_OE_value_V5(owner_password, out_encryption_key, out_U, out_O, out_OE);  
1212 - out_Perms = compute_Perms_value_V5(out_encryption_key); 1172 + // Algorithm 8 from the PDF 2.0
  1173 + auto validation_salt = util::random_string(8);
  1174 + auto key_salt = util::random_string(8);
  1175 + out_U = hash_V5(user_password, validation_salt, "").append(validation_salt).append(key_salt);
  1176 + auto intermediate_key = hash_V5(user_password, key_salt, "");
  1177 + out_UE = process_with_aes(intermediate_key, true, out_encryption_key);
  1178 + // Algorithm 9 from the PDF 2.0
  1179 + validation_salt = util::random_string(8);
  1180 + key_salt = util::random_string(8);
  1181 + out_O = hash_V5(owner_password, validation_salt, out_U) + validation_salt + key_salt;
  1182 + intermediate_key = hash_V5(owner_password, key_salt, out_U);
  1183 + out_OE = process_with_aes(intermediate_key, true, out_encryption_key);
  1184 + // Algorithm 10 from the PDF 2.0
  1185 + out_Perms = process_with_aes(out_encryption_key, true, compute_Perms_value_V5_clear());
1213 setV5EncryptionParameters(out_O, out_OE, out_U, out_UE, out_Perms); 1186 setV5EncryptionParameters(out_O, out_OE, out_U, out_UE, out_Perms);
1214 } 1187 }
1215 1188