C crypt（）在md5模式下无法正常工作？

Question

I'm using the crypt() function for the first time in c. I'm just running some initial tests, so none of this is actually going to be used, the constant salt value in particular. :)

I run the following code:

crypt(password, "$1$k7de83ka7");

From my understanding of the crypt docs, this provided salt value should specify that crypt() run in MD5 mode, which will produce a hash of the format "$1$". The $1$ specifies the value was hashed with MD5. That's how I understand it should work.

However, when I test the above code, the value returned is "$1ciFuWRySk3A", so it seems to be missing one of the '$' chars. Am I doing something wrong to cause this problem?

Answer 1

crypt(password, "$1$k7de83ka7");

I don't think you're calling crypt correctly, from the man page:

If salt is a character string starting with the characters "$id$" followed by a string terminated by "$" : $id$salt$encrypted

Then id identifies the encryption method.

And you shouldn't expect it to return a string containing $ (not necessarily)

On success, a pointer to the encrypted password is returned. On error, NULL is returned.