ZIP_FOPEN_ENCRYPTED(3)

ZIP_FOPEN_ENCRYPTED(3) | Library Functions Manual | ZIP_FOPEN_ENCRYPTED(3)

# NAME

`zip_fopen_encrypted`, `zip_fopen_index_encrypted` — open encrypted file in zip archive for reading

# LIBRARY

libzip (-lzip)

# SYNOPSIS

`#include <zip.h>`

zip_file_t *
`zip_fopen_encrypted`(zip_t *archive, const char *fname, zip_flags_t flags, const char *password);

zip_file_t *
`zip_fopen_index_encrypted`(zip_t *archive, zip_uint64_t index, zip_flags_t flags, const char *password);

# DESCRIPTION

The `zip_fopen_encrypted`() function opens the encrypted file name fname in archive using the password given in the password argument. If password is `NULL` or the empty string, the default password is used (see zip_set_default_password(3)). The flags argument are the same as for zip_fopen(3).

The `zip_fopen_index_encrypted`() function opens the file at position index, see zip_fopen_index(3). These functions are called automatically by zip_fopen(3); you only need to call them if you want to specify a non-default password (see zip_set_default_password(3)).

# RETURN VALUES

Upon successful completion, a struct zip_file pointer is returned. Otherwise, `NULL` is returned and the error code in archive is set to indicate the error.

# ERRORS

[`ZIP_ER_NOPASSWD`]
  No password was provided.

The function `zip_fopen_encrypted`() may also fail and set zip_err for any of the errors specified for the routine zip_fopen(3).

The function `zip_fopen_index_encrypted`() may also fail and set zip_err for any of the errors specified for the routine zip_fopen_index(3).

# SEE ALSO

libzip(3), zip_fclose(3), zip_fopen(3), zip_fread(3), zip_get_num_entries(3), zip_name_locate(3)

# HISTORY

`zip_fopen_encrypted`() and `zip_fopen_index_encrypted`() were added in libzip 1.0.

# AUTHORS

Dieter Baron <dillo@nih.at> and Thomas Klausner <wiz@gatalith.at>

# CAVEATS

The zip file format provides very limited possibility for password verification (a short hash of is compared against one byte in the zip archive). For this reason, reading a file while using an incorrect password may immediately fail with `ZIP_ER_WRONGPASSWD`, but if the mismatch is not detected, a zlib error may be returned later instead. Since zlib errors can also be caused by broken compressed data, there is no way to make sure if the password was incorrect or if it was correct, but the compressed data was invalid.

September 15, 2020 | NiH