slog2_obfuscate()
Obfuscate file and directory names by replacing some characters
Synopsis:
#include <sys/slog2.h>
int slog2_obfuscate( slog2_obf_t obf_type,
char obf_char,
uint32_t flags,
const char *input,
size_t size,
char *output );
Arguments:
- obf_type
- The type of input that needs to be obfuscated:
- SLOG2_OBF_FILEPATH ̵ the input is a filepath, which could include directory name(s), a file name, and an extension.
- obf_char
- The character to use for obfuscation.
If you set this to the null character (i.e., '\0'), then slog2_obfuscate() uses
slog2_hash()
to fill in the obfuscated characters.
Typical values used are
x
or a period. - flags
- Reserved for future use. Set this to 0.
- input
- A null-terminated input string (UTF-8) to be obfuscated (e.g., personally identifiable information, such as a file name).
- size
- The size of the output buffer.
- output
- A buffer where the function can store the resulting obfuscated string buffer. The string is null-terminated.
Library:
libslog2-extra
Use the -l slog2-extra option to qcc to link against this library.
Description:
The slog2_obfuscate() function creates an obfuscated version of a string by replacing portions of it with a given character.
The obfuscated output string length is truncated to size - 1 characters if the output buffer is smaller than the size required to store input.
When obf_char isn't the null character, the resulting obfuscated output string always produces the same output for a given string. When obf_char is the null character, the obfuscated output string value will be identical within a similar timeframe across all processes.
For file and directory names:
- Three- or four-character extensions aren't obfuscated.
- If the name is six characters or longer, then the first two characters and the last two characters (plus the file extension) are left unchanged.
- If the name is shorter than six characters, then the first and last character (plus file extension) are left unchanged.
For example (using .
as the replacement character):
| Before | After |
|---|---|
| dir/file.txt | d.r/f..e.txt |
| my_fav_dir/my_file.txt | my......ir/my...le.txt |
Because this function depends on the random number generator, make sure that /dev/random is running before you start slogger2.
Returns:
0 on success, or -1 if an error occurred.
Classification:
| Safety: | |
|---|---|
| Cancellation point | No |
| Signal handler | Yes |
| Thread | Yes |