salfter/infnoise
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

fix buffer size for multiplier mode

Browse Source
This commit is contained in:
Manuel Domke
2018-08-11 23:16:50 +02:00
parent 2534f78730
commit 8a930f2783
3 changed files with 41 additions and 25 deletions
Download Patch File Download Diff File Expand all files Collapse all files

48
software/libinfnoise.c
View File

@@ -25,6 +25,7 @@
uint8_t keccakState[KeccakPermutationSizeInBytes];
bool initInfnoise(struct infnoise_context *context, char *serial, bool keccak, bool debug) {
context->message="";
prepareOutputBuffer();
// initialize health check
@@ -45,6 +46,7 @@ bool initInfnoise(struct infnoise_context *context, char *serial, bool keccak, b
if (keccak) {
KeccakInitialize();
KeccakInitializeState(keccakState);
//fprintf(stderr, "debug: keccak init: %s\n", context->message);
}
// let healthcheck collect some data
@@ -97,6 +99,7 @@ uint32_t extractBytes(uint8_t *bytes, uint8_t *inBuf, char **message, bool *erro
if (!inmHealthCheckAddBit(evenBit, oddBit, even)) {
*message = "Health check of Infinite Noise Multiplier failed!";
*errorFlag = true;
fprintf(stderr, "Error: %s\n", *message);
return 0;
}
}
@@ -111,12 +114,12 @@ uint32_t extractBytes(uint8_t *bytes, uint8_t *inBuf, char **message, bool *erro
// outputMultiplier is 0, we output only as many bits as we measure in entropy.
// This allows a user to generate hundreds of MiB per second if needed, for use
// as cryptographic keys.
uint32_t processBytes(uint8_t *bytes, uint8_t *result, uint32_t entropy,
uint32_t processBytes(uint8_t *bytes, uint8_t *result, uint32_t *entropy,
bool raw, uint32_t outputMultiplier, char **message, bool *errorFlag) {
//Use the lower of the measured entropy and the provable lower bound on
//average entropy.
if (entropy > inmExpectedEntropyPerBit * BUFLEN / INM_ACCURACY) {
entropy = inmExpectedEntropyPerBit * BUFLEN / INM_ACCURACY;
if (*entropy > inmExpectedEntropyPerBit * BUFLEN / INM_ACCURACY) {
*entropy = inmExpectedEntropyPerBit * BUFLEN / INM_ACCURACY;
}
if (raw) {
// In raw mode, we just output raw data from the INM.
@@ -134,21 +137,22 @@ uint32_t processBytes(uint8_t *bytes, uint8_t *result, uint32_t entropy,
// gets a snapshot of the keccak state. BUFLEN must be a multiple of 64, since
// Keccak-1600 uses 64-bit "lanes".
KeccakAbsorb(keccakState, bytes, BUFLEN / 64u);
uint8_t dataOut[16u * 8u]; // ???
if (outputMultiplier == 0u) {
uint8_t dataOut[*entropy/8u]; // ???
// Output all the bytes of entropy we have
KeccakExtract(keccakState, dataOut, (entropy + 63u) / 64u);
KeccakExtract(keccakState, dataOut, (*entropy + 63u) / 64u);
if (result != NULL) {
memcpy(result, dataOut, entropy / 8u * sizeof(uint8_t));
memcpy(result, dataOut, *entropy / 8u * sizeof(uint8_t));
}
return entropy / 8u;
return *entropy / 8u;
}
// Output 256*outputMultipler bits.
uint32_t numBits = outputMultiplier * 256u;
uint32_t bytesWritten = 0u;
uint8_t dataOut[outputMultiplier * 32u]; // ???
while (numBits > 0u) {
// Write up to 1024 bits at a time.
uint32_t bytesToWrite = 1024u / 8u;
@@ -156,30 +160,34 @@ uint32_t processBytes(uint8_t *bytes, uint8_t *result, uint32_t entropy,
bytesToWrite = numBits / 8u;
}
KeccakExtract(keccakState, dataOut, bytesToWrite / 8u);
uint32_t entropyThisTime = entropy;
uint32_t entropyThisTime = *entropy;
if (entropyThisTime > 8u * bytesToWrite) {
entropyThisTime = 8u * bytesToWrite;
}
memcpy(result + bytesWritten, dataOut, bytesToWrite * sizeof(uint8_t)); // ?
// memcpy(result + bytesWritten, dataOut, bytesToWrite * sizeof(uint8_t)); // ?
// alternative: loop through dataOut and append array elements to result..
// if (result != NULL) {
// for (uint32_t i = 0; i < bytesToWrite; i++) {
// result[bytesWritten + i] = dataOut[i];
// }
// }
if (result != NULL) {
for (uint32_t i = 0; i < bytesToWrite; i++) {
result[bytesWritten + i] = dataOut[i];
}
}
//fprintf(stderr, "bytesWritten: %ul\n", bytesWritten);
//fprintf(stderr, "entropy: %ul\n", *entropy);
bytesWritten += bytesToWrite;
numBits -= bytesToWrite * 8u;
entropy -= entropyThisTime;
*entropy -= entropyThisTime;
if (numBits > 0u) {
KeccakPermutation(keccakState);
}
}
if (bytesWritten != outputMultiplier * (256u / 8u)) {
*message = "Internal error outputting bytes";
//fprintf(stderr, "ERROR: %ul", bytesWritten);
*errorFlag = true;
return 0;
}
//fprintf(stderr, "bytesWritten_end: %ul\n", bytesWritten);
return bytesWritten;
}
@@ -339,6 +347,7 @@ uint32_t readData(struct infnoise_context *context, uint8_t *result, bool raw, u
if (ftdi_read_data(&context->ftdic, inBuf, BUFLEN) != BUFLEN) {
context->message = "USB read failed";
context->errorFlag = true;
return 0;
}
struct timespec end;
@@ -347,10 +356,13 @@ uint32_t readData(struct infnoise_context *context, uint8_t *result, bool raw, u
if (us <= MAX_MICROSEC_FOR_SAMPLES) {
uint8_t bytes[BUFLEN / 8u];
context->entropyThisTime = extractBytes(bytes, inBuf, &context->message, &context->errorFlag);
if (context->errorFlag) {
//fprintf(stderr, "ERROR1: %ul\n", context->entropyThisTime);
return 0;
}
// call health check and return bytes if OK
if (inmHealthCheckOkToUseData() && inmEntropyOnTarget(context->entropyThisTime, BUFLEN)) {
return processBytes(bytes, result, context->entropyThisTime, raw, outputMultiplier, &context->message,
return processBytes(bytes, result, &context->entropyThisTime, raw, outputMultiplier, &context->message,
&context->errorFlag);
}
}