/* * Message Digests Module * * Provides commands to calculate a message digest using a specified hash algorithm. * * Copyright (C) 2023 Brian O'Hagan * */ #include "tlsInt.h" #include "tclOpts.h" #include <tcl.h> #include <stdio.h> #include <string.h> #include <openssl/evp.h> /* Constants */ const char *hex = "0123456789ABCDEF"; /* Macros */ #define BUFFER_SIZE 65536 #define BIN_FORMAT 0 #define HEX_FORMAT 1 #define CHAN_EOF 0x10 /* * This structure describes the per-instance state of an SSL channel. * * The SSL processing context is maintained here, in the ClientData */ typedef struct DigestState { Tcl_Channel self; /* This socket channel */ Tcl_TimerToken timer; /* Timer for read events */ int flags; /* Chan config flags */ int watchMask; /* Current WatchProc mask */ int mode; /* Current mode of parent channel */ int format; /* Output format */ Tcl_Interp *interp; /* Current interpreter */ EVP_MD_CTX *ctx; /* MD Context */ HMAC_CTX *hctx; /* HMAC Context */ Tcl_Command token; /* Command token */ } DigestState; /* *------------------------------------------------------------------- * * Tls_DigestNew -- * * This function creates a digest state structure * * Returns: * Digest structure pointer * * Side effects: * Creates structure * *------------------------------------------------------------------- */ DigestState *Tls_DigestNew(Tcl_Interp *interp, int format) { DigestState *statePtr = NULL; statePtr = (DigestState *) ckalloc((unsigned) sizeof(DigestState)); if (statePtr != NULL) { memset(statePtr, 0, sizeof(DigestState)); statePtr->self = NULL; /* This socket channel */ statePtr->timer = NULL; /* Timer to flush data */ statePtr->flags = 0; /* Chan config flags */ statePtr->watchMask = 0; /* Current WatchProc mask */ statePtr->mode = 0; /* Current mode of parent channel */ statePtr->format = format; /* Output format */ statePtr->interp = interp; /* Current interpreter */ statePtr->ctx = NULL; /* MD Context */ statePtr->hctx = NULL; /* HMAC Context */ } return statePtr; } /* *------------------------------------------------------------------- * * Tls_DigestFree -- * * This function removes a digest state structure * * Returns: * Nothing * * Side effects: * Removes structure * *------------------------------------------------------------------- */ void Tls_DigestFree(DigestState *statePtr) { if (statePtr == (DigestState *) NULL) return; if (statePtr->ctx != (EVP_MD_CTX *) NULL) { EVP_MD_CTX_free(statePtr->ctx); } if (statePtr->hctx != (HMAC_CTX *) NULL) { HMAC_CTX_free(statePtr->hctx); } ckfree(statePtr); } /*******************************************************************/ /* *------------------------------------------------------------------- * * Tls_DigestInit -- * * Initialize a hash function * * Returns: * TCL_OK if successful or TCL_ERROR for failure with result set * to error message. * * Side effects: * No result or error message * *------------------------------------------------------------------- */ int Tls_DigestInit(Tcl_Interp *interp, DigestState *statePtr, const EVP_MD *md, Tcl_Obj *keyObj) { int key_len, res; const unsigned char *key; /* Create message digest context */ if (keyObj == NULL) { statePtr->ctx = EVP_MD_CTX_new(); res = (statePtr->ctx != NULL); } else { statePtr->hctx = HMAC_CTX_new(); res = (statePtr->hctx != NULL); } if (!res) { Tcl_AppendResult(interp, "Create digest context failed: ", REASON(), NULL); return TCL_ERROR; } /* Initialize hash function */ if (keyObj == NULL) { res = EVP_DigestInit_ex(statePtr->ctx, md, NULL); } else { key = Tcl_GetByteArrayFromObj(keyObj, &key_len); res = HMAC_Init_ex(statePtr->hctx, (const void *) key, key_len, md, NULL); } if (!res) { Tcl_AppendResult(interp, "Initialize digest failed: ", REASON(), NULL); return TCL_ERROR; } return TCL_OK; } /* *------------------------------------------------------------------- * * Tls_DigestUpdate -- * * Update a hash function * * Returns: * 1 if successful or 0 for failure * * Side effects: * Adds buf to hash function * *------------------------------------------------------------------- */ int Tls_DigestUpdate(DigestState *statePtr, char *buf, size_t read) { int res; if (statePtr->ctx != NULL) { res = EVP_DigestUpdate(statePtr->ctx, buf, read); } else { res = HMAC_Update(statePtr->hctx, buf, read); } return res; } /* *------------------------------------------------------------------- * * Tls_DigestFinialize -- * * Finalize a hash function and generate a message digest * * Returns: * TCL_OK if successful or TCL_ERROR for failure with result set * to error message. * * Side effects: * Sets result to message digest for hash function or an error message. * *------------------------------------------------------------------- */ int Tls_DigestFinialize(Tcl_Interp *interp, DigestState *statePtr) { unsigned char md_buf[EVP_MAX_MD_SIZE]; unsigned int md_len; int res; /* Finalize hash function and calculate message digest */ if (statePtr->ctx != NULL) { res = EVP_DigestFinal_ex(statePtr->ctx, md_buf, &md_len); } else { res = HMAC_Final(statePtr->hctx, md_buf, &md_len); } if (!res) { Tcl_AppendResult(interp, "Finalize digest failed: ", REASON(), NULL); return TCL_ERROR; } /* Return message digest as either a binary or hex string */ if (statePtr->format == BIN_FORMAT) { Tcl_SetObjResult(interp, Tcl_NewByteArrayObj(md_buf, md_len)); } else { Tcl_Obj *resultObj = Tcl_NewObj(); unsigned char *ptr = Tcl_SetByteArrayLength(resultObj, md_len*2); for (unsigned int i = 0; i < md_len; i++) { *ptr++ = hex[(md_buf[i] >> 4) & 0x0F]; *ptr++ = hex[md_buf[i] & 0x0F]; } Tcl_SetObjResult(interp, resultObj); } return TCL_OK; } /*******************************************************************/ /* *------------------------------------------------------------------- * * Tls_DigestFile -- * * Return message digest for file using user specified hash function. * * Returns: * TCL_OK or TCL_ERROR * * Side effects: * Result is message digest or error message * *------------------------------------------------------------------- */ int Tls_DigestFile(Tcl_Interp *interp, Tcl_Obj *filename, const EVP_MD *md, int format, Tcl_Obj *keyObj) { DigestState *statePtr; Tcl_Channel chan = NULL; unsigned char buf[BUFFER_SIZE]; int res = TCL_OK, len; /* Open file channel */ chan = Tcl_FSOpenFileChannel(interp, filename, "rb", 0444); if (chan == (Tcl_Channel) NULL) { return TCL_ERROR; } /* Configure channel */ if (Tcl_SetChannelOption(interp, chan, "-translation", "binary") == TCL_ERROR) { res = TCL_ERROR; goto done; } Tcl_SetChannelBufferSize(chan, BUFFER_SIZE); /* Create struct */ if ((statePtr = Tls_DigestNew(interp, format)) == NULL) { res = TCL_ERROR; goto done; } /* Initialize hash function */ if ((res = Tls_DigestInit(interp, statePtr, md, keyObj)) != TCL_OK) { goto done; } /* Read file data and update hash function */ while (!Tcl_Eof(chan)) { len = Tcl_ReadRaw(chan, (char *) buf, BUFFER_SIZE); if (len > 0) { if (!Tls_DigestUpdate(statePtr, &buf[0], (size_t) len)) { Tcl_AppendResult(interp, "Update digest failed: ", REASON(), NULL); res = TCL_ERROR; goto done; } } } /* Finalize hash function and calculate message digest */ res = Tls_DigestFinialize(interp, statePtr); done: /* Close channel */ if (Tcl_Close(interp, chan) == TCL_ERROR) { chan = (Tcl_Channel) NULL; res = TCL_ERROR; goto done; } /* Clean-up */ Tls_DigestFree(statePtr); return res; } /*******************************************************************/ /* *------------------------------------------------------------------- * * DigestBlockModeProc -- * * This function is invoked by the generic IO level * to set blocking and nonblocking modes. * * Returns: * 0 if successful or POSIX error code if failed. * * Side effects: * Sets the device into blocking or nonblocking mode. * Can call Tcl_SetChannelError. * *------------------------------------------------------------------- */ static int DigestBlockModeProc(ClientData clientData, int mode) { DigestState *statePtr = (DigestState *) clientData; if (mode == TCL_MODE_NONBLOCKING) { statePtr->flags |= TLS_TCL_ASYNC; } else { statePtr->flags &= ~(TLS_TCL_ASYNC); } return 0; } /* *------------------------------------------------------------------- * * DigestCloseProc -- * * This function is invoked by the generic IO level to perform * channel-type-specific cleanup when channel is closed. All * queued output is flushed prior to calling this function. * * Returns: * 0 if successful or POSIX error code if failed. * * Side effects: * Writes digest to output and closes the channel. Stores error * messages in interp result. * *------------------------------------------------------------------- */ int DigestCloseProc(ClientData clientData, Tcl_Interp *interp) { DigestState *statePtr = (DigestState *) clientData; /* Cancel active timer, if any */ if (statePtr->timer != (Tcl_TimerToken) NULL) { Tcl_DeleteTimerHandler(statePtr->timer); statePtr->timer = (Tcl_TimerToken) NULL; } /* Clean-up */ Tls_DigestFree(statePtr); return 0; } /* * Same as DigestCloseProc but with individual read and write close control */ static int DigestClose2Proc(ClientData instanceData, Tcl_Interp *interp, int flags) { if ((flags & (TCL_CLOSE_READ | TCL_CLOSE_WRITE)) == 0) { return DigestCloseProc(instanceData, interp); } return EINVAL; } /* *---------------------------------------------------------------------- * * DigestInputProc -- * * Called by the generic IO system to read data from transform and * place in buf. * * Returns: * Total bytes read or -1 for an error along with a POSIX error * code in errorCodePtr. Use EAGAIN for nonblocking and no data. * * Side effects: * Read data from transform and write to buf * *---------------------------------------------------------------------- */ int DigestInputProc(ClientData clientData, char *buf, int toRead, int *errorCodePtr) { DigestState *statePtr = (DigestState *) clientData; Tcl_Channel parent; int read, res; *errorCodePtr = 0; if (toRead <= 0 || statePtr->self == (Tcl_Channel) NULL) { return 0; } /* Get bytes from underlying channel */ parent = Tcl_GetStackedChannel(statePtr->self); read = Tcl_ReadRaw(parent, buf, toRead); /* Update hash function */ if (read > 0) { if (!Tls_DigestUpdate(statePtr, buf, (size_t) read)) { Tcl_SetChannelError(statePtr->self, Tcl_ObjPrintf("Digest update failed: %s", REASON())); *errorCodePtr = EINVAL; return -1; } /* This is correct */ read = -1; *errorCodePtr = EAGAIN; } else if (read < 0) { /* Error */ *errorCodePtr = Tcl_GetErrno(); } else if (!(statePtr->flags & CHAN_EOF)) { /* EOF */ *errorCodePtr = 0; unsigned char md_buf[EVP_MAX_MD_SIZE]; unsigned int md_len = 0; /* Finalize hash function and calculate message digest */ if (statePtr->ctx != NULL) { res = EVP_DigestFinal_ex(statePtr->ctx, md_buf, &md_len); } else { res = HMAC_Final(statePtr->hctx, md_buf, &md_len); } if (!res) { *errorCodePtr = EINVAL; /* Write message digest to output channel as byte array or hex string */ } else if (md_len > 0) { if (statePtr->format == BIN_FORMAT && toRead >= (int) md_len) { read = md_len; memcpy(buf, md_buf, read); } else if(statePtr->format == HEX_FORMAT && toRead >= (int) (md_len*2)) { unsigned char hex_buf[EVP_MAX_MD_SIZE*2]; unsigned char *ptr = hex_buf; for (unsigned int i = 0; i < md_len; i++) { *ptr++ = hex[(md_buf[i] >> 4) & 0x0F]; *ptr++ = hex[md_buf[i] & 0x0F]; } read = md_len*2; memcpy(buf, hex_buf, read); } } statePtr->flags |= CHAN_EOF; } return read; } /* *---------------------------------------------------------------------- * * DigestOutputProc -- * * Called by the generic IO system to write data in buf to transform. * * Returns: * Total bytes written or -1 for an error along with a POSIX error * code in errorCodePtr. Use EAGAIN for nonblocking and can't write data. * * Side effects: * Get data from buf and update digest * *---------------------------------------------------------------------- */ int DigestOutputProc(ClientData clientData, const char *buf, int toWrite, int *errorCodePtr) { DigestState *statePtr = (DigestState *) clientData; *errorCodePtr = 0; if (toWrite <= 0 || statePtr->self == (Tcl_Channel) NULL) { return 0; } /* Update hash function */ if (toWrite > 0 && !Tls_DigestUpdate(statePtr, buf, (size_t) toWrite)) { Tcl_SetChannelError(statePtr->self, Tcl_ObjPrintf("Digest update failed: %s", REASON())); *errorCodePtr = EINVAL; return -1; } return toWrite; } /* *---------------------------------------------------------------------- * * DigestSetOptionProc -- * * Called by the generic IO system to set channel option name to value. * * Returns: * TCL_OK if successful or TCL_ERROR if failed along with an error * message in interp and Tcl_SetErrno. * * Side effects: * Updates channel option to new value. * *---------------------------------------------------------------------- */ static int DigestSetOptionProc(ClientData clientData, Tcl_Interp *interp, const char *optionName, const char *optionValue) { DigestState *statePtr = (DigestState *) clientData; Tcl_Channel parent; Tcl_DriverSetOptionProc *setOptionProc; if (statePtr->self == (Tcl_Channel) NULL) { return TCL_ERROR; } /* Delegate options downstream */ parent = Tcl_GetStackedChannel(statePtr->self); setOptionProc = Tcl_ChannelSetOptionProc(Tcl_GetChannelType(parent)); if (setOptionProc != NULL) { return (*setOptionProc)(Tcl_GetChannelInstanceData(parent), interp, optionName, optionValue); } else { Tcl_SetErrno(EINVAL); return Tcl_BadChannelOption(interp, optionName, NULL); } } /* *---------------------------------------------------------------------- * * DigestGetOptionProc -- * * Called by the generic IO system to get channel option name's value. * * Returns: * TCL_OK if successful or TCL_ERROR if failed along with an error * message in interp and Tcl_SetErrno. * * Side effects: * Sets result to option's value * *---------------------------------------------------------------------- */ static int DigestGetOptionProc(ClientData clientData, Tcl_Interp *interp, const char *optionName, Tcl_DString *optionValue) { DigestState *statePtr = (DigestState *) clientData; Tcl_Channel parent; Tcl_DriverGetOptionProc *getOptionProc; if (statePtr->self == (Tcl_Channel) NULL) { return TCL_ERROR; } /* Delegate options downstream */ parent = Tcl_GetStackedChannel(statePtr->self); getOptionProc = Tcl_ChannelGetOptionProc(Tcl_GetChannelType(parent)); if (getOptionProc != NULL) { return (*getOptionProc)(Tcl_GetChannelInstanceData(parent), interp, optionName, optionValue); } else if (optionName == (char*) NULL) { /* Request is query for all options, this is ok. */ return TCL_OK; } else { Tcl_SetErrno(EINVAL); return Tcl_BadChannelOption(interp, optionName, NULL); } } /* *---------------------------------------------------------------------- * * DigestTimerHandler -- * * Called by the notifier via timer to flush out pending input data. * * Returns: * Nothing * * Side effects: * May call Tcl_NotifyChannel * *---------------------------------------------------------------------- */ static void DigestTimerHandler(ClientData clientData) { DigestState *statePtr = (DigestState *) clientData; if (statePtr->self == (Tcl_Channel) NULL) { return; } /* Clear timer token */ statePtr->timer = (Tcl_TimerToken) NULL; /* Fire event if there is pending data, skip otherwise */ if ((statePtr->watchMask & TCL_READABLE) && (Tcl_InputBuffered(statePtr->self) > 0)) { Tcl_NotifyChannel(statePtr->self, TCL_READABLE); } } /* *---------------------------------------------------------------------- * * DigestWatchProc -- * * Initialize the notifier to watch for events from this channel. * * Returns: * Nothing * * Side effects: * Configure notifier so future events on the channel will be seen by Tcl. * *---------------------------------------------------------------------- */ #define READ_DELAY 5 void DigestWatchProc(ClientData clientData, int mask) { DigestState *statePtr = (DigestState *) clientData; Tcl_Channel parent; Tcl_DriverWatchProc *watchProc; if (statePtr->self == (Tcl_Channel) NULL) { return; } /* Store OR-ed combination of TCL_READABLE, TCL_WRITABLE and TCL_EXCEPTION */ statePtr->watchMask = mask; /* Propagate mask info to parent channel */ parent = Tcl_GetStackedChannel(statePtr->self); watchProc = Tcl_ChannelWatchProc(Tcl_GetChannelType(parent)); watchProc(Tcl_GetChannelInstanceData(parent), mask); /* Remove pending timer */ if (statePtr->timer != (Tcl_TimerToken) NULL) { Tcl_DeleteTimerHandler(statePtr->timer); statePtr->timer = (Tcl_TimerToken) NULL; } /* If there is data pending, set new timer to call Tcl_NotifyChannel */ if ((mask & TCL_READABLE) && (Tcl_InputBuffered(statePtr->self) > 0)) { statePtr->timer = Tcl_CreateTimerHandler(READ_DELAY, DigestTimerHandler, (ClientData) statePtr); } } /* *---------------------------------------------------------------------- * * DigestGetHandleProc -- * * Called from Tcl_GetChannelHandle to retrieve OS specific file handle * from inside this channel. Not used for transformations? * * Returns: * TCL_OK for success or TCL_ERROR for error or if not supported. If * direction is TCL_READABLE, sets handlePtr to the handle used for * input, or if TCL_WRITABLE sets to the handle used for output. * * Side effects: * None * *---------------------------------------------------------------------- */ int DigestGetHandleProc(ClientData clientData, int direction, ClientData *handlePtr) { DigestState *statePtr = (DigestState *) clientData; if (statePtr->self == (Tcl_Channel) NULL) { return TCL_ERROR; } return Tcl_GetChannelHandle(Tcl_GetStackedChannel(statePtr->self), direction, handlePtr); } /* *---------------------------------------------------------------------- * * DigestNotifyProc -- * * Called by Tcl to inform us of activity on the underlying channel. * * Returns: * Unchanged interestMask which is an OR-ed combination of TCL_READABLE or TCL_WRITABLE * * Side effects: * Cancels any pending timer. * *---------------------------------------------------------------------- */ int DigestNotifyProc(ClientData clientData, int interestMask) { DigestState *statePtr = (DigestState *) clientData; /* Skip timer event as redundant */ if (statePtr->timer != (Tcl_TimerToken) NULL) { Tcl_DeleteTimerHandler(statePtr->timer); statePtr->timer = (Tcl_TimerToken) NULL; } return interestMask; } /* * * Channel type structure definition for digest transformations. * */ static const Tcl_ChannelType digestChannelType = { "digest", /* Type name */ TCL_CHANNEL_VERSION_5, /* v5 channel */ DigestCloseProc, /* Close proc */ DigestInputProc, /* Input proc */ DigestOutputProc, /* Output proc */ NULL, /* Seek proc */ DigestSetOptionProc, /* Set option proc */ DigestGetOptionProc, /* Get option proc */ DigestWatchProc, /* Initialize notifier */ DigestGetHandleProc, /* Get OS handles out of channel */ DigestClose2Proc, /* close2proc */ DigestBlockModeProc, /* Set blocking/nonblocking mode*/ NULL, /* Flush proc */ DigestNotifyProc, /* Handling of events bubbling up */ NULL, /* Wide seek proc */ NULL, /* Thread action */ NULL /* Truncate */ }; /* *---------------------------------------------------------------------- * * Tls_DigestChannel -- * * Create a stacked channel for a message digest transformation. * * Returns: * TCL_OK or TCL_ERROR * * Side effects: * Adds transform to channel and sets result to channel name or error message. * *---------------------------------------------------------------------- */ static int Tls_DigestChannel(Tcl_Interp *interp, const char *channel, const EVP_MD *md, int format, Tcl_Obj *keyObj) { int mode; /* OR-ed combination of TCL_READABLE and TCL_WRITABLE */ Tcl_Channel chan; DigestState *statePtr; EVP_MD_CTX *ctx = (EVP_MD_CTX *) NULL; HMAC_CTX *hctx = (HMAC_CTX *) NULL; /* Validate args */ if (channel == (const char *) NULL || md == (const EVP_MD *) NULL) { return TCL_ERROR; } chan = Tcl_GetChannel(interp, channel, &mode); if (chan == (Tcl_Channel) NULL) { return TCL_ERROR; } /* Make sure to operate on the topmost channel */ chan = Tcl_GetTopChannel(chan); /* Create struct */ if ((statePtr = Tls_DigestNew(interp, format)) == NULL) { Tcl_AppendResult(interp, "Initialize digest error: memory allocation failure", (char *) NULL); return TCL_ERROR; } statePtr->self = chan; statePtr->mode = mode; /* Initialize hash function */ if (Tls_DigestInit(interp, statePtr, md, keyObj) != TCL_OK) { return TCL_ERROR; } /* Configure channel */ Tcl_SetChannelOption(interp, chan, "-translation", "binary"); if (Tcl_GetChannelBufferSize(chan) < EVP_MAX_MD_SIZE * 2) { Tcl_SetChannelBufferSize(chan, EVP_MAX_MD_SIZE * 2); } /* Stack channel */ statePtr->self = Tcl_StackChannel(interp, &digestChannelType, (ClientData) statePtr, mode, chan); if (statePtr->self == (Tcl_Channel) NULL) { Tls_DigestFree(statePtr); return TCL_ERROR; } Tcl_SetResult(interp, (char *) Tcl_GetChannelName(chan), TCL_VOLATILE); return TCL_OK; } /* *---------------------------------------------------------------------- * * Unstack Channel -- * * This function is invoked to process the "unstack" TCL command. * See the user documentation for details on what it does. * * Returns: * TCL_OK or TCL_ERROR * * Side effects: * Removes transform from channel or sets result to error message. * *---------------------------------------------------------------------- */ static int UnstackObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) { Tcl_Channel chan; int mode; /* OR-ed combination of TCL_READABLE and TCL_WRITABLE */ if (objc != 2) { Tcl_WrongNumArgs(interp, 1, objv, "channel"); return TCL_ERROR; } /* Get channel */ chan = Tcl_GetChannel(interp, Tcl_GetStringFromObj(objv[1], NULL), &mode); if (chan == (Tcl_Channel) NULL) { return TCL_ERROR; } /* Make sure to operate on the topmost channel */ chan = Tcl_GetTopChannel(chan); /* Check if digest channel */ if (Tcl_GetChannelType(chan) != &digestChannelType) { Tcl_AppendResult(interp, "bad channel \"", Tcl_GetChannelName(chan), "\": not a digest channel", NULL); Tcl_SetErrorCode(interp, "TLS", "UNSTACK", "CHANNEL", "INVALID", (char *) NULL); return TCL_ERROR; } /* Pop transform from channel, leaves error info in interp result */ if (Tcl_UnstackChannel(interp, chan) == TCL_ERROR) { return TCL_ERROR; } return TCL_OK; clientData = clientData; } /*******************************************************************/ static const char *instance_fns [] = { "finalize", "update", NULL }; /* *------------------------------------------------------------------- * * InstanceObjCmd -- * * Handler for digest accumulator command instances. * * Returns: * TCL_OK or TCL_ERROR * * Side effects: * Adds data to hash or returns message digest * *------------------------------------------------------------------- */ int InstanceObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) { DigestState *statePtr = (DigestState *) clientData; int fn, len = 0; char *buf = NULL; if (objc < 2 || objc > 3) { Tcl_WrongNumArgs(interp, 1, objv, "function ?data?"); return TCL_ERROR; } /* Function */ if (Tcl_GetIndexFromObj(interp, objv[1], instance_fns, "function", 0, &fn) != TCL_OK) { return TCL_ERROR; } /* Do function */ if (fn) { /* Update hash function */ if (objc == 3) { buf = Tcl_GetByteArrayFromObj(objv[2], &len); } else { Tcl_WrongNumArgs(interp, 1, objv, "update data"); return TCL_ERROR; } if (!Tls_DigestUpdate(statePtr, buf, (size_t) len)) { Tcl_SetObjResult(interp, Tcl_ObjPrintf("Digest update failed: %s", REASON())); return TCL_ERROR; } } else { /* Finalize hash function and calculate message digest */ if (Tls_DigestFinialize(interp, statePtr) != TCL_OK) { Tcl_SetObjResult(interp, Tcl_ObjPrintf("Digest finalize failed: %s", REASON())); return TCL_ERROR; } Tcl_DeleteCommandFromToken(interp, statePtr->token); } return TCL_OK; } /* *------------------------------------------------------------------- * * InstanceDelCallback -- * * Callback to clean-up when digest instance command is deleted. * * Returns: * Nothing * * Side effects: * Destroys struct * *------------------------------------------------------------------- */ void InstanceDelCallback(ClientData clientData) { DigestState *statePtr = (DigestState *) clientData; /* Clean-up */ Tls_DigestFree(statePtr); } /* *------------------------------------------------------------------- * * Tls_DigestInstance -- * * Create command to allow user to add data to hash function. * * Returns: * TCL_OK or TCL_ERROR * * Side effects: * Creates command or error message * *------------------------------------------------------------------- */ int Tls_DigestInstance(Tcl_Interp *interp, Tcl_Obj *cmdObj, const EVP_MD *md, int format, Tcl_Obj *keyObj) { DigestState *statePtr; char *cmdName = Tcl_GetStringFromObj(cmdObj, NULL); /* Create struct */ if ((statePtr = Tls_DigestNew(interp, format)) == NULL) { Tcl_AppendResult(interp, "Initialize digest error: memory allocation failure", (char *) NULL); return TCL_ERROR; } /* Initialize hash function */ if (Tls_DigestInit(interp, statePtr, md, keyObj) != TCL_OK) { return TCL_ERROR; } /* Create instance command */ statePtr->token = Tcl_CreateObjCommand(interp, cmdName, InstanceObjCmd, (ClientData) statePtr, InstanceDelCallback); /* Return command name */ Tcl_SetObjResult(interp, cmdObj); return TCL_OK; } /*******************************************************************/ /* *------------------------------------------------------------------- * * Tls_DigestData -- * * Calculate message digest using hash function. * * Returns: * TCL_OK or TCL_ERROR * * Side effects: * Sets result to message digest or error message * *------------------------------------------------------------------- */ int Tls_DigestData(Tcl_Interp *interp, int objc, Tcl_Obj *const objv[], const EVP_MD *md, int format, Tcl_Obj *keyObj) { char *data; int len, res; unsigned int md_len; unsigned char md_buf[EVP_MAX_MD_SIZE]; if (objc != 2) { Tcl_WrongNumArgs(interp, 1, objv, "data"); return TCL_ERROR; } /* Get data */ data = Tcl_GetByteArrayFromObj(objv[1], &len); if (data == NULL || len == 0) { Tcl_SetResult(interp, "No data", NULL); return TCL_ERROR; } /* Calculate digest based on hash function */ if (keyObj == (Tcl_Obj *) NULL) { res = EVP_Digest(data, (size_t) len, md_buf, &md_len, md, NULL); } else { unsigned char *key, *hmac = NULL; int key_len; key = Tcl_GetByteArrayFromObj(keyObj, &key_len); hmac = HMAC(md, (const void *) key, key_len, (const unsigned char *) data, (size_t) len, md_buf, &md_len); res = (hmac != NULL); } /* Output digest to result per format (bin or hex) */ if (res) { if (format == BIN_FORMAT) { Tcl_SetObjResult(interp, Tcl_NewByteArrayObj(md_buf, md_len)); } else { Tcl_Obj *resultObj = Tcl_NewObj(); unsigned char *ptr = Tcl_SetByteArrayLength(resultObj, md_len*2); for (unsigned int i = 0; i < md_len; i++) { *ptr++ = hex[(md_buf[i] >> 4) & 0x0F]; *ptr++ = hex[md_buf[i] & 0x0F]; } Tcl_SetObjResult(interp, resultObj); } } else { Tcl_AppendResult(interp, "Hash calculation error:", REASON(), (char *) NULL); return TCL_ERROR; } return TCL_OK; } /*******************************************************************/ /* *------------------------------------------------------------------- * * DigestObjCmd -- * * Return message digest using user specified hash function. * * Returns: * TCL_OK or TCL_ERROR * * Side effects: * Sets result to message digest or error message * *------------------------------------------------------------------- */ static int DigestObjCmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) { int idx, len, format = HEX_FORMAT, key_len = 0, data_len = 0, res = TCL_ERROR; const char *digestname, *channel = NULL; Tcl_Obj *cmdObj = NULL, *dataObj = NULL, *fileObj = NULL, *keyObj = NULL; unsigned char *key = NULL; const EVP_MD *md; Tcl_ResetResult(interp); if (objc < 3 || objc > 7) { Tcl_WrongNumArgs(interp, 1, objv, "type ?-bin|-hex? ?-key hmac_key? [-channel chan | -command cmdName | -file filename | ?-data? data]"); return TCL_ERROR; } /* Get digest */ digestname = Tcl_GetStringFromObj(objv[1], &len); if (digestname == NULL || (md = EVP_get_digestbyname(digestname)) == NULL) { Tcl_AppendResult(interp, "Invalid digest type \"", digestname, "\"", NULL); return TCL_ERROR; } /* Optimal case for blob of data */ if (objc == 3) { return Tls_DigestData(interp, --objc, ++objv, md, format, NULL); } /* Get options */ for (idx = 2; idx < objc-1; idx++) { char *opt = Tcl_GetStringFromObj(objv[idx], NULL); if (opt[0] != '-') break; OPTFLAG("-bin", format, BIN_FORMAT); OPTFLAG("-binary", format, BIN_FORMAT); OPTFLAG("-hex", format, HEX_FORMAT); OPTFLAG("-hexadecimal", format, HEX_FORMAT); OPTOBJ("-data", dataObj); OPTSTR("-chan", channel); OPTSTR("-channel", channel); OPTOBJ("-command", cmdObj); OPTOBJ("-file", fileObj); OPTOBJ("-filename", fileObj); OPTOBJ("-key", keyObj); OPTBAD("option", "-bin, -channel, -command, -data, -file, -filename, -hex, or -key"); return TCL_ERROR; } /* If no option for last arg, then its the data */ if (idx < objc) { dataObj = objv[idx]; } /* Calc digest on file, stacked channel, or data blob */ if (fileObj != NULL) { res = Tls_DigestFile(interp, fileObj, md, format, keyObj); } else if (channel != NULL) { res = Tls_DigestChannel(interp, channel, md, format, keyObj); } else if (cmdObj != NULL) { res = Tls_DigestInstance(interp, cmdObj, md, format, keyObj); } else if (dataObj != NULL) { Tcl_Obj *objs[2]; objs[0] = NULL; objs[1] = dataObj; res = Tls_DigestData(interp, 2, objs, md, format, keyObj); } return res; } /* *------------------------------------------------------------------- * * Message Digest Convenience Commands -- * * Convenience commands for message digests. * * Returns: * TCL_OK or TCL_ERROR * * Side effects: * Sets result to message digest or error message * *------------------------------------------------------------------- */ int DigestMD4Cmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) { return Tls_DigestData(interp, objc, objv, EVP_md4(), HEX_FORMAT, NULL); } int DigestMD5Cmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) { return Tls_DigestData(interp, objc, objv, EVP_md5(), HEX_FORMAT, NULL); } int DigestSHA1Cmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) { return Tls_DigestData(interp, objc, objv, EVP_sha1(), HEX_FORMAT, NULL); } int DigestSHA256Cmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) { return Tls_DigestData(interp, objc, objv, EVP_sha256(), HEX_FORMAT, NULL); } int DigestSHA512Cmd(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]) { return Tls_DigestData(interp, objc, objv, EVP_sha512(), HEX_FORMAT, NULL); } /* *------------------------------------------------------------------- * * Tls_DigestCommands -- * * Create digest commands * * Returns: * TCL_OK or TCL_ERROR * * Side effects: * Creates commands * *------------------------------------------------------------------- */ int Tls_DigestCommands(Tcl_Interp *interp) { Tcl_CreateObjCommand(interp, "tls::digest", DigestObjCmd, (ClientData) 0, (Tcl_CmdDeleteProc *) NULL); Tcl_CreateObjCommand(interp, "tls::md4", DigestMD4Cmd, (ClientData) 0, (Tcl_CmdDeleteProc *) NULL); Tcl_CreateObjCommand(interp, "tls::md5", DigestMD5Cmd, (ClientData) 0, (Tcl_CmdDeleteProc *) NULL); Tcl_CreateObjCommand(interp, "tls::sha1", DigestSHA1Cmd, (ClientData) 0, (Tcl_CmdDeleteProc *) NULL); Tcl_CreateObjCommand(interp, "tls::sha256", DigestSHA256Cmd, (ClientData) 0, (Tcl_CmdDeleteProc *) NULL); Tcl_CreateObjCommand(interp, "tls::sha512", DigestSHA512Cmd, (ClientData) 0, (Tcl_CmdDeleteProc *) NULL); Tcl_CreateObjCommand(interp, "tls::unstack", UnstackObjCmd, (ClientData) 0, (Tcl_CmdDeleteProc *) NULL); return TCL_OK; }