Initial QSfera import

Server/vendor/github.com/amoghe/go-crypt/crypt.go

@@ -0,0 +1,59 @@
+// +build freebsd netbsd
+
+// Package crypt provides wrappers around functions available in crypt.h
+//
+// It wraps around the GNU specific extension (crypt) when the reentrant version
+// (crypt_r) is unavailable. The non-reentrant version is guarded by a global lock
+// so as to be safely callable from concurrent goroutines.
+package crypt
+
+import (
+	"sync"
+	"unsafe"
+)
+
+/*
+#cgo LDFLAGS: -lcrypt
+#define _GNU_SOURCE
+#include <stdlib.h>
+#include <unistd.h>
+*/
+import "C"
+
+var (
+	mu sync.Mutex
+)
+
+// Crypt provides a wrapper around the glibc crypt() function.
+// For the meaning of the arguments, refer to the README.
+func Crypt(pass, salt string) (string, error) {
+	c_pass := C.CString(pass)
+	defer C.free(unsafe.Pointer(c_pass))
+
+	c_salt := C.CString(salt)
+	defer C.free(unsafe.Pointer(c_salt))
+
+	mu.Lock()
+	c_enc, err := C.crypt(c_pass, c_salt)
+	mu.Unlock()
+
+	if c_enc == nil {
+		return "", err
+	}
+	defer C.free(unsafe.Pointer(c_enc))
+
+	// From the crypt(3) man-page. Upon error, crypt_r writes an invalid
+	// hashed passphrase to the output field of their data argument, and
+	// crypt writes an invalid hash to its static storage area. This
+	// string will be shorter than 13 characters, will begin with a ‘*’,
+	// and will not compare equal to setting.
+	hash := C.GoString(c_enc)
+	if len(hash) > 0 && hash[0] == '*' {
+		return "", err
+	}
+
+	// Return nil error if the string is non-nil.
+	// As per the errno.h manpage, functions are allowed to set errno
+	// on success. Caller should ignore errno on success.
+	return C.GoString(c_enc), err
+}