diff options
Diffstat (limited to 'transaction.go')
| -rw-r--r-- | transaction.go | 62 |
1 files changed, 59 insertions, 3 deletions
diff --git a/transaction.go b/transaction.go index 31a6dbc..96bff63 100644 --- a/transaction.go +++ b/transaction.go @@ -1,11 +1,21 @@ // Package pam provides a wrapper for the PAM application API. package pam +//#cgo CFLAGS: -Wall -std=c99 +//#cgo LDFLAGS: -lpam +// //#include <security/pam_appl.h> //#include <stdlib.h> //#include <stdint.h> -//#cgo CFLAGS: -Wall -std=c99 -//#cgo LDFLAGS: -lpam +// +//#ifdef PAM_BINARY_PROMPT +//#define BINARY_PROMPT_IS_SUPPORTED 1 +//#else +//#include <limits.h> +//#define PAM_BINARY_PROMPT INT_MAX +//#define BINARY_PROMPT_IS_SUPPORTED 0 +//#endif +// //void init_pam_conv(struct pam_conv *conv, uintptr_t); //int pam_start_confdir(const char *service_name, const char *user, const struct pam_conv *pam_conversation, const char *confdir, pam_handle_t **pamh) __attribute__ ((weak)); //int check_pam_start_confdir(void); @@ -36,6 +46,9 @@ const ( // TextInfo indicates the conversation handler should display some // text. TextInfo = C.PAM_TEXT_INFO + // BinaryPrompt indicates the conversation handler that should implement + // the private binary protocol + BinaryPrompt = C.PAM_BINARY_PROMPT ) // ConversationHandler is an interface for objects that can be used as @@ -47,6 +60,23 @@ type ConversationHandler interface { RespondPAM(Style, string) (string, error) } +// BinaryPointer exposes the type used for the data in a binary conversation +// it represents a pointer to data that is produced by the module and that +// must be parsed depending on the protocol in use +type BinaryPointer unsafe.Pointer + +// BinaryConversationHandler is an interface for objects that can be used as +// conversation callbacks during PAM authentication if binary protocol is going +// to be supported. +type BinaryConversationHandler interface { + ConversationHandler + // RespondPAMBinary receives a pointer to the binary message. It's up to + // the receiver to parse it according to the protocol specifications. + // The function can return a byte array that will passed as pointer back + // to the module. + RespondPAMBinary(BinaryPointer) ([]byte, error) +} + // ConversationFunc is an adapter to allow the use of ordinary functions as // conversation callbacks. type ConversationFunc func(Style, string) (string, error) @@ -57,14 +87,29 @@ func (f ConversationFunc) RespondPAM(s Style, msg string) (string, error) { } // cbPAMConv is a wrapper for the conversation callback function. +// //export cbPAMConv func cbPAMConv(s C.int, msg *C.char, c C.uintptr_t) (*C.char, C.int) { var r string var err error v := cgo.Handle(c).Value() + style := Style(s) switch cb := v.(type) { + case BinaryConversationHandler: + if style == BinaryPrompt { + bytes, err := cb.RespondPAMBinary(BinaryPointer(msg)) + if err != nil { + return nil, C.PAM_CONV_ERR + } + return (*C.char)(C.CBytes(bytes)), C.PAM_SUCCESS + } else { + r, err = cb.RespondPAM(style, C.GoString(msg)) + } case ConversationHandler: - r, err = cb.RespondPAM(Style(s), C.GoString(msg)) + if style == BinaryPrompt { + return nil, C.PAM_AUTHINFO_UNAVAIL + } + r, err = cb.RespondPAM(style, C.GoString(msg)) } if err != nil { return nil, C.PAM_CONV_ERR @@ -117,6 +162,12 @@ func StartConfDir(service, user string, handler ConversationHandler, confDir str } func start(service, user string, handler ConversationHandler, confDir string) (*Transaction, error) { + switch handler.(type) { + case BinaryConversationHandler: + if !CheckPamHasBinaryProtocol() { + return nil, errors.New("BinaryConversationHandler() was used, but it is not supported by this platform") + } + } t := &Transaction{ conv: &C.struct_pam_conv{}, c: cgo.NewHandle(handler), @@ -339,3 +390,8 @@ func (t *Transaction) GetEnvList() (map[string]string, error) { func CheckPamHasStartConfdir() bool { return C.check_pam_start_confdir() == 0 } + +// CheckPamHasBinaryProtocol return if pam on system supports PAM_BINARY_PROMPT +func CheckPamHasBinaryProtocol() bool { + return C.BINARY_PROMPT_IS_SUPPORTED != 0 +} |