/*
* Information Commands Module
*
* Provides commands that return info related to the OpenSSL config and data.
*
* Copyright (C) 2023 Brian O'Hagan
*
*/
#include "tlsInt.h"
#include "tclOpts.h"
#include <openssl/crypto.h>
#include <openssl/ssl.h>
#include <openssl/safestack.h>
/*
* Valid SSL and TLS Protocol Versions
*/
static const char *protocols[] = {
"ssl2", "ssl3", "tls1", "tls1.1", "tls1.2", "tls1.3", NULL
};
enum protocol {
TLS_SSL2, TLS_SSL3, TLS_TLS1, TLS_TLS1_1, TLS_TLS1_2, TLS_TLS1_3, TLS_NONE
};
/*
*-------------------------------------------------------------------
*
* NamesCallback --
*
* Callback to add algorithm or method names to a TCL list object.
*
* Results:
* Append name to TCL list object.
*
* Side effects:
* None.
*
*-------------------------------------------------------------------
*/
void NamesCallback(const OBJ_NAME *obj, void *arg) {
Tcl_Obj *objPtr = (Tcl_Obj *) arg;
if (1 || !obj->alias) {
/* Filter out signed digests (a.k.a signature algorithms) */
if (strstr(obj->name, "rsa") == NULL && strstr(obj->name, "RSA") == NULL) {
Tcl_ListObjAppendElement(NULL, objPtr, Tcl_NewStringObj(obj->name,-1));
}
}
}
/*
*-------------------------------------------------------------------
*
* CiphersObjCmd --
*
* This procedure is invoked to process the "tls::ciphers" command
* to list available ciphers, based upon protocol selected.
*
* Results:
* A standard Tcl result list.
*
* Side effects:
* constructs and destroys SSL context (CTX)
*
*-------------------------------------------------------------------
*/
static int CiphersObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) {
Tcl_Obj *objPtr = NULL;
SSL_CTX *ctx = NULL;
SSL *ssl = NULL;
STACK_OF(SSL_CIPHER) *sk;
char *cp, buf[BUFSIZ];
int index, verbose = 0, use_supported = 0;
const SSL_METHOD *method;
dprintf("Called");
if ((objc < 1) || (objc > 4)) {
Tcl_WrongNumArgs(interp, 1, objv, "?protocol? ?verbose? ?supported?");
return TCL_ERROR;
}
if (objc == 1) {
/* List all ciphers */
Tcl_Obj *objPtr = Tcl_NewListObj(0, NULL);
#if OPENSSL_VERSION_NUMBER < 0x10100000L
OpenSSL_add_all_ciphers(); /* Make sure they're loaded */
#endif
OBJ_NAME_do_all(OBJ_NAME_TYPE_CIPHER_METH, NamesCallback, (void *) objPtr);
Tcl_ResetResult(interp);
Tcl_SetObjResult(interp, objPtr);
return TCL_OK;
} else if (Tcl_GetIndexFromObj(interp, objv[1], protocols, "protocol", 0, &index) != TCL_OK) {
return TCL_ERROR;
}
if ((objc > 2) && Tcl_GetBooleanFromObj(interp, objv[2], &verbose) != TCL_OK) {
return TCL_ERROR;
}
if ((objc > 3) && Tcl_GetBooleanFromObj(interp, objv[3], &use_supported) != TCL_OK) {
return TCL_ERROR;
}
ERR_clear_error();
switch ((enum protocol)index) {
case TLS_SSL2:
#if OPENSSL_VERSION_NUMBER >= 0x10100000L || defined(NO_SSL2) || defined(OPENSSL_NO_SSL2)
Tcl_AppendResult(interp, protocols[index], ": protocol not supported", NULL);
return TCL_ERROR;
#else
method = SSLv2_method(); break;
#endif
case TLS_SSL3:
#if defined(NO_SSL3) || defined(OPENSSL_NO_SSL3) || defined(OPENSSL_NO_SSL3_METHOD)
Tcl_AppendResult(interp, protocols[index], ": protocol not supported", NULL);
return TCL_ERROR;
#else
method = SSLv3_method(); break;
#endif
case TLS_TLS1:
#if defined(NO_TLS1) || defined(OPENSSL_NO_TLS1) || defined(OPENSSL_NO_TLS1_METHOD)
Tcl_AppendResult(interp, protocols[index], ": protocol not supported", NULL);
return TCL_ERROR;
#else
method = TLSv1_method(); break;
#endif
case TLS_TLS1_1:
#if defined(NO_TLS1_1) || defined(OPENSSL_NO_TLS1_1) || defined(OPENSSL_NO_TLS1_1_METHOD)
Tcl_AppendResult(interp, protocols[index], ": protocol not supported", NULL);
return TCL_ERROR;
#else
method = TLSv1_1_method(); break;
#endif
case TLS_TLS1_2:
#if defined(NO_TLS1_2) || defined(OPENSSL_NO_TLS1_2) || defined(OPENSSL_NO_TLS1_2_METHOD)
Tcl_AppendResult(interp, protocols[index], ": protocol not supported", NULL);
return TCL_ERROR;
#else
method = TLSv1_2_method(); break;
#endif
case TLS_TLS1_3:
#if defined(NO_TLS1_3) || defined(OPENSSL_NO_TLS1_3)
Tcl_AppendResult(interp, protocols[index], ": protocol not supported", NULL);
return TCL_ERROR;
#else
method = TLS_method();
SSL_CTX_set_min_proto_version(ctx, TLS1_3_VERSION);
SSL_CTX_set_max_proto_version(ctx, TLS1_3_VERSION);
break;
#endif
default:
method = TLS_method();
break;
}
ctx = SSL_CTX_new(method);
if (ctx == NULL) {
Tcl_AppendResult(interp, REASON(), NULL);
return TCL_ERROR;
}
ssl = SSL_new(ctx);
if (ssl == NULL) {
Tcl_AppendResult(interp, REASON(), NULL);
SSL_CTX_free(ctx);
return TCL_ERROR;
}
/* Use list and order as would be sent in a ClientHello or all available ciphers */
if (use_supported) {
sk = SSL_get1_supported_ciphers(ssl);
} else {
sk = SSL_get_ciphers(ssl);
}
if (sk != NULL) {
if (!verbose) {
objPtr = Tcl_NewListObj(0, NULL);
for (int i = 0; i < sk_SSL_CIPHER_num(sk); i++) {
const SSL_CIPHER *c = sk_SSL_CIPHER_value(sk, i);
if (c == NULL) continue;
/* cipher name or (NONE) */
cp = SSL_CIPHER_get_name(c);
if (cp == NULL) break;
Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj(cp, -1));
}
} else {
objPtr = Tcl_NewStringObj("",0);
for (int i = 0; i < sk_SSL_CIPHER_num(sk); i++) {
/* uint32_t id;*/
const SSL_CIPHER *c = sk_SSL_CIPHER_value(sk, i);
if (c == NULL) continue;
/* Get OpenSSL-specific ID, not IANA ID */
/*id = SSL_CIPHER_get_id(c);*/
/* TLS protocol two-byte id */
/*id = SSL_CIPHER_get_protocol_id(c);*/
/* Standard RFC name of cipher or (NONE) */
/*const char *nm = SSL_CIPHER_standard_name(c);
if (nm == NULL) {nm = "UNKNOWN";}*/
/* textual description of the cipher */
if (SSL_CIPHER_description(c, buf, sizeof(buf)) != NULL) {
Tcl_AppendToObj(objPtr, buf, (Tcl_Size) strlen(buf));
} else {
Tcl_AppendToObj(objPtr, "UNKNOWN\n", 8);
}
}
}
if (use_supported) {
sk_SSL_CIPHER_free(sk);
}
}
SSL_free(ssl);
SSL_CTX_free(ctx);
Tcl_SetObjResult(interp, objPtr);
return TCL_OK;
clientData = clientData;
}
/*
*-------------------------------------------------------------------
*
* DigestsObjCmd --
*
* Return a list of all valid hash algorithms or message digests.
*
* Results:
* A standard Tcl list.
*
* Side effects:
* None.
*
*-------------------------------------------------------------------
*/
int DigestsObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) {
Tcl_Obj *objPtr = Tcl_NewListObj(0, NULL);
#if OPENSSL_VERSION_NUMBER < 0x10100000L
OpenSSL_add_all_digests(); /* Make sure they're loaded */
#endif
OBJ_NAME_do_all(OBJ_NAME_TYPE_MD_METH, NamesCallback, (void *) objPtr);
Tcl_SetObjResult(interp, objPtr);
return TCL_OK;
clientData = clientData;
objc = objc;
objv = objv;
}
/*
*-------------------------------------------------------------------
*
* ProtocolsObjCmd --
*
* Return a list of the available or supported SSL/TLS protocols.
*
* Results:
* A standard Tcl list.
*
* Side effects:
* none
*
*-------------------------------------------------------------------
*/
static int
ProtocolsObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) {
Tcl_Obj *objPtr;
dprintf("Called");
if (objc != 1) {
Tcl_WrongNumArgs(interp, 1, objv, NULL);
return TCL_ERROR;
}
ERR_clear_error();
objPtr = Tcl_NewListObj(0, NULL);
#if OPENSSL_VERSION_NUMBER < 0x10100000L && !defined(NO_SSL2) && !defined(OPENSSL_NO_SSL2)
Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj(protocols[TLS_SSL2], -1));
#endif
#if !defined(NO_SSL3) && !defined(OPENSSL_NO_SSL3) && !defined(OPENSSL_NO_SSL3_METHOD)
Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj(protocols[TLS_SSL3], -1));
#endif
#if !defined(NO_TLS1) && !defined(OPENSSL_NO_TLS1) && !defined(OPENSSL_NO_TLS1_METHOD)
Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj(protocols[TLS_TLS1], -1));
#endif
#if !defined(NO_TLS1_1) && !defined(OPENSSL_NO_TLS1_1) && !defined(OPENSSL_NO_TLS1_1_METHOD)
Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj(protocols[TLS_TLS1_1], -1));
#endif
#if !defined(NO_TLS1_2) && !defined(OPENSSL_NO_TLS1_2) && !defined(OPENSSL_NO_TLS1_2_METHOD)
Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj(protocols[TLS_TLS1_2], -1));
#endif
#if !defined(NO_TLS1_3) && !defined(OPENSSL_NO_TLS1_3)
Tcl_ListObjAppendElement(interp, objPtr, Tcl_NewStringObj(protocols[TLS_TLS1_3], -1));
#endif
Tcl_SetObjResult(interp, objPtr);
return TCL_OK;
clientData = clientData;
}
/*
*-------------------------------------------------------------------
*
* VersionObjCmd --
*
* Return a string with the OpenSSL version info.
*
* Results:
* A standard Tcl result.
*
* Side effects:
* None.
*
*-------------------------------------------------------------------
*/
static int
VersionObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) {
Tcl_Obj *objPtr;
dprintf("Called");
objPtr = Tcl_NewStringObj(OPENSSL_VERSION_TEXT, -1);
Tcl_SetObjResult(interp, objPtr);
return TCL_OK;
clientData = clientData;
objc = objc;
objv = objv;
}
/*
*-------------------------------------------------------------------
*
* Tls_InfoCommands --
*
* Create info commands
*
* Returns:
* TCL_OK or TCL_ERROR
*
* Side effects:
* Creates commands
*
*-------------------------------------------------------------------
*/
int Tls_InfoCommands(Tcl_Interp *interp) {
Tcl_CreateObjCommand(interp, "tls::ciphers", CiphersObjCmd, (ClientData) 0, (Tcl_CmdDeleteProc *) NULL);
Tcl_CreateObjCommand(interp, "tls::digests", DigestsObjCmd, (ClientData) 0, (Tcl_CmdDeleteProc *) NULL);
Tcl_CreateObjCommand(interp, "tls::protocols", ProtocolsObjCmd, (ClientData) 0, (Tcl_CmdDeleteProc *) NULL);
Tcl_CreateObjCommand(interp, "tls::version", VersionObjCmd, (ClientData) 0, (Tcl_CmdDeleteProc *) NULL);
return TCL_OK;
}
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