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Diffstat (limited to 'src/noscryptutil.c')
| -rw-r--r-- | src/noscryptutil.c | 910 |
1 files changed, 910 insertions, 0 deletions
diff --git a/src/noscryptutil.c b/src/noscryptutil.c new file mode 100644 index 0000000..4cee2c3 --- /dev/null +++ b/src/noscryptutil.c @@ -0,0 +1,910 @@ +/* +* Copyright (c) 2024 Vaughn Nugent +* +* Package: noscrypt +* File: noscryptutil.h +* +* This library is free software; you can redistribute it and/or +* modify it under the terms of the GNU Lesser General Public License +* as published by the Free Software Foundation; either version 2.1 +* of the License, or (at your option) any later version. +* +* This library is distributed in the hope that it will be useful, +* but WITHOUT ANY WARRANTY; without even the implied warranty of +* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +* Lesser General Public License for more details. +* +* You should have received a copy of the GNU Lesser General Public License +* along with noscrypt. If not, see http://www.gnu.org/licenses/. +*/ + + +#include <stdlib.h> + +#include "nc-util.h" +#include "nc-crypto.h" + +#include <noscryptutil.h> + +/* +* Validation macros +*/ + +#ifdef NC_EXTREME_COMPAT + #error "Utilities library must be disabled when using extreme compat mode" +#endif /* NC_EXTREME_COMPAT */ + +#define MIN_PADDING_SIZE 0x20u +#define NIP44_VERSION_SIZE 0x01u +#define NIP44_PT_LEN_SIZE sizeof(uint16_t) + +/* +* minimum size for a valid nip44 payload +* 1 byte version + 32 byte nonce + 32 byte mac + 2 byte ptSize + 32bytes minimum length +*/ +#define NIP44_MIN_PAYLOAD_SIZE (NIP44_VERSION_SIZE + 0x20 + 0x02 + 0x20 + 0x02) + +/* +* Max payload size is the maximum size of the encrypted message +* 1 byte version + 32 byte nonce + 32 byte mac + maximum ciphertext size +*/ +#define NIP44_MAX_PAYLOAD_SIZE (NIP44_VERSION_SIZE + 0x20 + 0x20 + NIP44_MAX_ENC_MESSAGE_SIZE) + +/* +* The minimum ciphertext size is the minimum padded size + the minimum +* size of the plaintext length field +*/ +#define NIP44_MIN_CIPHERTEXT_SIZE (MIN_PADDING_SIZE + NIP44_PT_LEN_SIZE) + + +#define _nc_mem_free(x) if(x != NULL) { free(x); x = NULL; } +#define _nc_mem_alloc(elements, size) calloc(elements, size); +#define ZERO_FILL ncCryptoSecureZero + +#ifndef NC_INPUT_VALIDATION_OFF + #define CHECK_INVALID_ARG(x, argPos) if(x == NULL) return NCResultWithArgPosition(E_INVALID_ARG, argPos); + #define CHECK_NULL_ARG(x, argPos) if(x == NULL) return NCResultWithArgPosition(E_NULL_PTR, argPos); + #define CHECK_ARG_RANGE(x, min, max, argPos) if(x < min || x > max) return NCResultWithArgPosition(E_ARGUMENT_OUT_OF_RANGE, argPos); + #define CHECK_ARG_IS(exp, argPos) if(!(exp)) return NCResultWithArgPosition(E_INVALID_ARG, argPos); +#else + /* empty macros */ + #define CHECK_INVALID_ARG(x) + #define CHECK_NULL_ARG(x, argPos) + #define CHECK_ARG_RANGE(x, min, max, argPos) + #define CHECK_ARG_IS(is, expected, argPos) +#endif /* !NC_DISABLE_INPUT_VALIDATION */ + +#ifdef _NC_IS_WINDOWS + + #include <math.h> + + /* performs a log2 on integer types */ + #define _math_int_log2(x) (uint32_t)log2((double)x) + +#else + /* + * GCC/clang does not expose log2 so we can use the __builtin_clz + * to find leading zeros of an integer and subtract that from 31 + * (bit positions) for int32 + */ + static _nc_fn_inline uint32_t _math_int_log2(uint32_t val) + { + DEBUG_ASSERT(val < UINT32_MAX); + + return 31 - __builtin_clz(val); + } +#endif + +/* Currently were on nip44 version 2 */ +static const uint8_t Nip44VersionValue[1] = { 0x02u }; + +struct cipher_buffer_state { + + cspan_t input; + span_t output; + + cspan_t actualOutput; +}; + +struct nc_util_enc_struct { + + uint32_t _flags; + + NCEncryptionArgs encArgs; + + struct cipher_buffer_state buffer; +}; + +static _nc_fn_inline span_t _ncUtilAllocSpan(uint32_t count, size_t size) +{ + span_t span; + +#if SIZE_MAX < UINT32_MAX + + if (count > SIZE_MAX) + { + return span; + } + +#endif + + span.data = _nc_mem_alloc((size_t)count, size); + span.size = (uint32_t)count; + + return span; +} + +static _nc_fn_inline void _ncUtilZeroSpan(span_t span) +{ + ZERO_FILL(span.data, span.size); +} + +static _nc_fn_inline void _ncUtilFreeSpan(span_t span) +{ + _nc_mem_free(span.data); +} + +static _nc_fn_inline uint32_t _calcNip44PtPadding(uint32_t plaintextSize) +{ + uint32_t chunk, nextPower, factor; + + /* + * Taken from https://github.com/nostr-protocol/nips/blob/master/44.md + * + * I believe the idea is to add consisten padding for some better + * disgusing of the plainText data. + */ + + if (plaintextSize <= MIN_PADDING_SIZE) + { + return MIN_PADDING_SIZE; + } + + /* Safe to subtract because pt > 0 */ + nextPower = _math_int_log2(plaintextSize - 1); + + nextPower += 1u; + + nextPower = 1 << nextPower; + + if (nextPower <= 256u) + { + chunk = 32u; + } + else + { + chunk = nextPower / 8u; + } + + factor = plaintextSize - 1; + + factor /= chunk; + + factor += 1; + + return chunk * factor; +} + +static _nc_fn_inline uint32_t _calcNip44TotalOutSize(uint32_t inputSize) +{ + uint32_t bufferSize; + + /* + * Buffer size for nip44 is calculated as follows: + * 1 byte for the version + * 32 bytes for the nonce + * 2 bytes for the length of the plainText + * ... padding size + * 32 bytes for the MAC + */ + + bufferSize = NIP44_VERSION_SIZE; + + bufferSize += NC_ENCRYPTION_NONCE_SIZE; + + bufferSize += NIP44_PT_LEN_SIZE; + + bufferSize += _calcNip44PtPadding(inputSize); + + bufferSize += NC_ENCRYPTION_MAC_SIZE; + + return bufferSize; +} + +static _nc_fn_inline span_t _nip44GetMacData(span_t payload) +{ + DEBUG_ASSERT(payload.size > NIP44_VERSION_SIZE + NC_ENCRYPTION_MAC_SIZE); + + /* + * The nip44 mac is computed over the nonce+encrypted ciphertext + * + * the ciphertext is the entire message buffer, so it includes + * version, nonce, data, padding, and mac space available. + * + * This function will return a span that points to the nonce+data + * segment of the buffer for mac computation. + * + * The nonce sits directly after the version byte, ct is after, + * and the remaining 32 bytes are for the mac. So that means + * macData = ct.size - version.size + mac.size + */ + + return ncSpanSlice( + payload, + NIP44_VERSION_SIZE, + payload.size - (NIP44_VERSION_SIZE + NC_ENCRYPTION_MAC_SIZE) + ); +} + +static _nc_fn_inline span_t _nip44GetMacOutput(span_t payload) +{ + DEBUG_ASSERT(payload.size > NC_ENCRYPTION_MAC_SIZE); + + /* + * Mac is the final 32 bytes of the ciphertext buffer + */ + return ncSpanSlice( + payload, + payload.size - NC_ENCRYPTION_MAC_SIZE, + NC_ENCRYPTION_MAC_SIZE + ); +} + +static _nc_fn_inline int _nip44ParseSegments( + cspan_t payload, + cspan_t* nonce, + cspan_t* mac, + cspan_t* macData, + cspan_t* cipherText +) +{ + if (payload.size < NIP44_MIN_PAYLOAD_SIZE) + { + return 0; + } + + /* slice after the version and before the mac segments */ + *nonce = ncSpanSliceC( + payload, + NIP44_VERSION_SIZE, + NC_ENCRYPTION_NONCE_SIZE + ); + + /* + * Mac is the final 32 bytes of the ciphertext buffer + */ + *mac = ncSpanSliceC( + payload, + payload.size - NC_ENCRYPTION_MAC_SIZE, + NC_ENCRYPTION_MAC_SIZE + ); + + /* + * The mac data is the nonce+ct segment of the buffer for mac computation. + */ + *macData = ncSpanSliceC( + payload, + NIP44_VERSION_SIZE, + payload.size - (NIP44_VERSION_SIZE + NC_ENCRYPTION_MAC_SIZE) + ); + + /* + * Ciphertext is after the nonce segment and before the mac segment + */ + *cipherText = ncSpanSliceC( + payload, + NIP44_VERSION_SIZE + NC_ENCRYPTION_NONCE_SIZE, + payload.size - (NIP44_VERSION_SIZE + NC_ENCRYPTION_NONCE_SIZE + NC_ENCRYPTION_MAC_SIZE) + ); + + return 1; +} + + +static _nc_fn_inline void _cipherPublishOutput(NCUtilCipherContext* buffer, uint32_t offset, uint32_t size) +{ + span_t slice; + + DEBUG_ASSERT(ncSpanIsValid(buffer->buffer.output)); + + if (size == 0) + { + ncSpanInitC(&buffer->buffer.actualOutput, NULL, 0); + } + else + { + /* use slice for debug guards */ + slice = ncSpanSlice(buffer->buffer.output, offset, size); + + /* init readonly span from mutable */ + ncSpanInitC( + &buffer->buffer.actualOutput, + ncSpanGetOffset(slice, 0), + ncSpanGetSize(slice) + ); + } +} + +/* +* I want the encryption/decyption functions to be indempodent +* meaning all mutations that happen can be repeated without +* side effects. IE no perminent state changes that can't be +* undone. +*/ + +static NCResult _nip44EncryptCompleteCore( + const NCContext* libContext, + const NCSecretKey* sk, + const NCPublicKey* pk, + NCUtilCipherContext* state +) +{ + + NCResult result; + cspan_t plainText; + span_t macData, macOutput, message; + uint32_t outPos; + uint8_t ptSize[NIP44_PT_LEN_SIZE]; + uint8_t hmacKeyOut[NC_ENCRYPTION_MAC_SIZE]; + NCEncryptionArgs encArgs; + + outPos = 0; + encArgs = state->encArgs; + message = state->buffer.output; + plainText = state->buffer.input; + + DEBUG_ASSERT(encArgs.version == NC_ENC_VERSION_NIP44); + + ZERO_FILL(hmacKeyOut, sizeof(hmacKeyOut)); + + /* Start by appending the version number */ + ncSpanAppend(message, &outPos, Nip44VersionValue, sizeof(Nip44VersionValue)); + + /* next is nonce data */ + ncSpanAppend(message, &outPos, encArgs.nonceData, NC_ENCRYPTION_NONCE_SIZE); + DEBUG_ASSERT(outPos == 1 + NC_ENCRYPTION_NONCE_SIZE); + + /* + * Assign the hmac key from the stack buffer. Since the args structure + * is copied, it won't leak the address to the stack buffer. + * + * Should always return success for nip44 because all properties are valid + * addresses. + */ + + result = NCSetEncryptionPropertyEx( + &encArgs, + NC_ENC_SET_NIP44_MAC_KEY, + hmacKeyOut, + sizeof(hmacKeyOut) + ); + + DEBUG_ASSERT(result == NC_SUCCESS); + + /* + * So this is the tricky part. The encryption operation appens directly + * on the ciphertext segment + * + * All current implementations allow overlapping input and output buffers + * so we can assign the pt segment on the encryption args + */ + + /* + * Since the message size and padding bytes will get encrypted, + * the buffer should currently point to the start of the encryption segment + * + * The size of the data to encrypt is the padded size plus the size of the + * plainText size field. + */ + + result = NCSetEncryptionData( + &encArgs, + ncSpanGetOffset(message, outPos), /* in place encryption */ + ncSpanGetOffset(message, outPos), + NIP44_PT_LEN_SIZE + _calcNip44PtPadding(plainText.size) /* Plaintext + pt size must be encrypted */ + ); + + DEBUG_ASSERT(result == NC_SUCCESS); + + /* big endian plaintext size */ + ptSize[0] = (uint8_t)(ncSpanGetSizeC(plainText) >> 8); + ptSize[1] = (uint8_t)(ncSpanGetSizeC(plainText) & 0xFF); + + /* + * Written position must point to the end of the padded ciphertext + * area which the plaintext is written to. + * + * The plaintext data will be encrypted in place. The encrypted + * data is the entired padded region containing the leading byte count + * the plaintext data, followed by zero padding. + */ + + ncSpanWrite(message, outPos, ptSize, sizeof(ptSize)); + + ncSpanWrite( + message, + outPos + NIP44_PT_LEN_SIZE, /* write pt directly after length */ + ncSpanGetOffsetC(plainText, 0), + ncSpanGetSizeC(plainText) + ); + + /* Move position pointer directly after final padding bytes */ + outPos += encArgs.dataSize; + + result = NCEncrypt(libContext, sk, pk, &encArgs); + + if (result != NC_SUCCESS) + { + return result; + } + + /* + MAC is computed over the nonce+encrypted data + this helper captures that data segment into a span + */ + + macData = _nip44GetMacData(message); + macOutput = _nip44GetMacOutput(message); + + result = NCComputeMac( + libContext, + hmacKeyOut, + ncSpanGetOffset(macData, 0), + ncSpanGetSize(macData), + ncSpanGetOffset(macOutput, 0) + ); + + if (result != NC_SUCCESS) + { + return result; + } + + outPos += NC_ENCRYPTION_MAC_SIZE; + + DEBUG_ASSERT2(outPos == message.size, "Buffer under/overflow detected"); + + /* publish all message bytes to output */ + _cipherPublishOutput(state, 0, outPos); + + /* zero hmac key before returning */ + ZERO_FILL(hmacKeyOut, sizeof(hmacKeyOut)); + + return NC_SUCCESS; +} + +static NCResult _nip44DecryptCompleteCore( + const NCContext* libContext, + const NCSecretKey* recvKey, + const NCPublicKey* sendKey, + NCUtilCipherContext* state +) +{ + NCResult result; + NCMacVerifyArgs macArgs; + NCEncryptionArgs encArgs; + cspan_t macData, macValue, nonce, payload, cipherText; + span_t output; + uint16_t ptSize; + + DEBUG_ASSERT(libContext && recvKey && sendKey && state); + DEBUG_ASSERT(state->encArgs.version == NC_ENC_VERSION_NIP44); + DEBUG_ASSERT(ncSpanGetSizeC(state->buffer.input) >= NIP44_MIN_PAYLOAD_SIZE); + + /* ensure decryption mode */ + DEBUG_ASSERT(state->_flags & NC_UTIL_CIPHER_MODE_DECRYPT); + + /* store local stack copy for safe mutation */ + encArgs = state->encArgs; + payload = state->buffer.input; + output = state->buffer.output; + + /* + * Copy the input buffer to the output buffer because the + * decryption happens in-place and needs a writable buffer + * + * After the operation is complete, we will assign the actual plaintext + * data to the actual output buffer + */ + + DEBUG_ASSERT2(ncSpanIsValid(output), "Output buffer was not allocated"); + + if (!_nip44ParseSegments(payload, &nonce, &macValue, &macData, &cipherText)) + { + return E_CIPHER_INVALID_FORMAT; + } + + /* Verify mac if the user allowed it */ + if ((state->_flags & NC_UTIL_CIPHER_MAC_NO_VERIFY) == 0) + { + DEBUG_ASSERT(ncSpanGetSizeC(macValue) == NC_ENCRYPTION_MAC_SIZE); + DEBUG_ASSERT(ncSpanGetSizeC(macData) > NC_ENCRYPTION_NONCE_SIZE + MIN_PADDING_SIZE); + + /* Assign the mac data to the mac verify args */ + macArgs.mac32 = ncSpanGetOffsetC(macValue, 0); + macArgs.nonce32 = ncSpanGetOffsetC(nonce, 0); + + /* message for verifying a mac in nip44 is the nonce+ciphertext */ + macArgs.payload = ncSpanGetOffsetC(macData, 0); + macArgs.payloadSize = ncSpanGetSizeC(macData); + + /* Verify the mac */ + result = NCVerifyMac(libContext, recvKey, sendKey, &macArgs); + + /* When the mac is invlaid */ + if (result == E_OPERATION_FAILED) + { + return E_CIPHER_MAC_INVALID; + } + /* argument errors */ + else if (result != NC_SUCCESS) + { + return result; + } + } + + /* + * manually assign nonce because it's a constant pointer which + * is not allowed when calling setproperty + */ + encArgs.nonceData = ncSpanGetOffsetC(nonce, 0); + + DEBUG_ASSERT2(cipherText.size >= MIN_PADDING_SIZE, "Cipertext segment was parsed incorrectly. Too small"); + + result = NCSetEncryptionData( + &encArgs, + ncSpanGetOffsetC(cipherText, 0), + ncSpanGetOffset(output, 0), /*decrypt ciphertext and write directly to the output buffer */ + ncSpanGetSizeC(cipherText) + ); + + DEBUG_ASSERT(result == NC_SUCCESS); + + /* + * If decryption was successful, the data should be written + * directly to the output buffer + */ + result = NCDecrypt(libContext, recvKey, sendKey, &encArgs); + + if (result != NC_SUCCESS) + { + return result; + } + + /* + * Parse CT length and assign the output buffer. + * + * PT size is stored at the beginning of the ciphertext + * segment and is 2 bytes in size, big endian. + */ + + ptSize = (uint16_t)(output.data[0] << 8 | output.data[1]); + + /* + * If the PT is corrupted or set maliciously, it can overrun + * the current buffer. The PT size must be less than the + * ciphertext size. + */ + if (!ncSpanIsValidRange(output, NIP44_PT_LEN_SIZE, ptSize)) + { + return E_OPERATION_FAILED; + } + + /* + * actual output span should now point to the decrypted plaintext + * data segment + */ + _cipherPublishOutput(state, NIP44_PT_LEN_SIZE, ptSize); + + DEBUG_ASSERT(ncSpanGetSizeC(state->buffer.actualOutput) < cipherText.size); + + return NC_SUCCESS; +} + +NC_EXPORT NCResult NC_CC NCUtilGetEncryptionPaddedSize(uint32_t encVersion, uint32_t plaintextSize) +{ + switch (encVersion) + { + default: + return E_VERSION_NOT_SUPPORTED; + + case NC_ENC_VERSION_NIP04: + return plaintextSize; + + case NC_ENC_VERSION_NIP44: + + /* + * Ensure the plaintext size if a nip44 message does not exceed the maximum size + */ + CHECK_ARG_IS(plaintextSize - 1 <= NIP44_MAX_ENC_MESSAGE_SIZE, 1); + + return (NCResult)(_calcNip44PtPadding(plaintextSize)); + } +} + +NC_EXPORT NCResult NC_CC NCUtilGetEncryptionBufferSize(uint32_t encVersion, uint32_t plaintextSize) +{ + + switch (encVersion) + { + default: + return E_VERSION_NOT_SUPPORTED; + + /* + * NIP-04 simply uses AES to 1:1 encrypt the plainText + * to ciphertext. + */ + case NC_ENC_VERSION_NIP04: + return plaintextSize; + + case NC_ENC_VERSION_NIP44: + return (NCResult)(_calcNip44TotalOutSize(plaintextSize)); + } +} + + +NC_EXPORT NCUtilCipherContext* NC_CC NCUtilCipherAlloc(uint32_t encVersion, uint32_t flags) +{ + NCUtilCipherContext* encCtx; + + /* + * Alloc context on heap + */ + encCtx = (NCUtilCipherContext*)_nc_mem_alloc(1, sizeof(NCUtilCipherContext)); + + if (encCtx != NULL) + { + encCtx->encArgs.version = encVersion; + encCtx->_flags = flags; + } + + return encCtx; +} + +NC_EXPORT void NC_CC NCUtilCipherFree(NCUtilCipherContext* encCtx) +{ + if (!encCtx) + { + return; + } + + /* + * If zero on free flag is set, we can zero all output memory + * before returning the buffer back to the heap + */ + if ((encCtx->_flags & NC_UTIL_CIPHER_ZERO_ON_FREE) > 0 && ncSpanIsValid(encCtx->buffer.output)) + { + _ncUtilZeroSpan(encCtx->buffer.output); + } + + /* Free output buffers (null buffers are allowed) */ + _ncUtilFreeSpan(encCtx->buffer.output); + + /* context can be released */ + _nc_mem_free(encCtx); +} + +NC_EXPORT NCResult NC_CC NCUtilCipherInit( + NCUtilCipherContext* encCtx, + const uint8_t* inputData, + uint32_t inputSize +) +{ + NCResult outputSize; + + CHECK_NULL_ARG(encCtx, 0); + CHECK_NULL_ARG(inputData, 1); + + if ((encCtx->_flags & NC_UTIL_CIPHER_MODE_DECRYPT) > 0) + { + /* + * Validate the input data for proper format for + * the current state version + */ + switch (encCtx->encArgs.version) + { + case NC_ENC_VERSION_NIP44: + { + if (inputSize < NIP44_MIN_PAYLOAD_SIZE) + { + return E_CIPHER_BAD_INPUT_SIZE; + } + + if (inputSize > NIP44_MAX_PAYLOAD_SIZE) + { + return E_CIPHER_BAD_INPUT_SIZE; + } + + /* Ensure the first byte is a valid version */ + if (inputData[0] != Nip44VersionValue[0]) + { + return E_VERSION_NOT_SUPPORTED; + } + + break; + } + default: + return E_VERSION_NOT_SUPPORTED; + } + + /* + * Alloc a the output buffer to be the same size as the input + * data for decryption because the output will always be equal + * or smaller than the input data. This is an over-alloc but + * that should be fine + */ + + outputSize = inputSize; + } + else + { + /* + * Calculate the correct output size to store the encryption + * data for the given state version + */ + outputSize = NCUtilGetEncryptionBufferSize(encCtx->encArgs.version, inputSize); + + if (outputSize < 0) + { + return E_CIPHER_BAD_INPUT_SIZE; + } + } + + DEBUG_ASSERT(outputSize > 0); + + /* + * If the buffer was previously allocated, the reuseable flag + * must be set to allow the buffer to be re-used for another + * operation. + */ + + if (ncSpanIsValid(encCtx->buffer.output)) + { + CHECK_ARG_IS((encCtx->_flags & NC_UTIL_CIPHER_REUSEABLE) > 0, 0); + + /* + * if the existing buffer is large enough to hold the new + * data reuse it, otherwise free it and allocate a new buffer + */ + + if (outputSize <= encCtx->buffer.output.size) + { + _ncUtilZeroSpan(encCtx->buffer.output); + + goto AssignInputAndExit; + } + else + { + _ncUtilFreeSpan(encCtx->buffer.output); + } + } + + /* Alloc output buffer within the struct */ + encCtx->buffer.output = _ncUtilAllocSpan((uint32_t)outputSize, sizeof(uint8_t)); + + if (!ncSpanIsValid(encCtx->buffer.output)) + { + return E_OUT_OF_MEMORY; + } + +AssignInputAndExit: + + /* Confirm output was allocated */ + DEBUG_ASSERT(ncSpanIsValid(encCtx->buffer.output)); + + /* Assign the input data span to point to the assigned input data */ + ncSpanInitC(&encCtx->buffer.input, inputData, inputSize); + + return NC_SUCCESS; +} + +NC_EXPORT NCResult NC_CC NCUtilCipherGetFlags(const NCUtilCipherContext* ctx) +{ + CHECK_NULL_ARG(ctx, 0); + + return (NCResult)(ctx->_flags); +} + +NC_EXPORT NCResult NC_CC NCUtilCipherGetOutputSize(const NCUtilCipherContext* encCtx) +{ + CHECK_NULL_ARG(encCtx, 0); + + if (!ncSpanIsValidC(encCtx->buffer.actualOutput)) + { + return E_CIPHER_NO_OUTPUT; + } + + return (NCResult)(encCtx->buffer.actualOutput.size); +} + +NC_EXPORT NCResult NC_CC NCUtilCipherReadOutput( + const NCUtilCipherContext* encCtx, + uint8_t* output, + uint32_t outputSize +) +{ + CHECK_NULL_ARG(encCtx, 0); + CHECK_NULL_ARG(output, 1); + + if (!ncSpanIsValidC(encCtx->buffer.actualOutput)) + { + return E_CIPHER_NO_OUTPUT; + } + + /* Buffer must be as large as the output data */ + CHECK_ARG_RANGE(outputSize, encCtx->buffer.actualOutput.size, UINT32_MAX, 2); + + ncSpanReadC( + encCtx->buffer.actualOutput, + output, + outputSize + ); + + return (NCResult)encCtx->buffer.actualOutput.size; +} + +NC_EXPORT NCResult NCUtilCipherSetProperty( + NCUtilCipherContext* ctx, + uint32_t property, + uint8_t* value, + uint32_t valueLen +) +{ + CHECK_NULL_ARG(ctx, 0) + + /* All other arguments are verified */ + return NCSetEncryptionPropertyEx( + &ctx->encArgs, + property, + value, + valueLen + ); +} + +NC_EXPORT NCResult NC_CC NCUtilCipherUpdate( + NCUtilCipherContext* encCtx, + const NCContext* libContext, + const NCSecretKey* sk, + const NCPublicKey* pk +) +{ + CHECK_NULL_ARG(encCtx, 0); + CHECK_NULL_ARG(libContext, 1); + CHECK_NULL_ARG(sk, 2); + CHECK_NULL_ARG(pk, 3); + + /* Make sure input & output buffers have been assigned/allocated */ + if (!ncSpanIsValid(encCtx->buffer.output)) + { + return E_INVALID_CONTEXT; + } + if (!ncSpanIsValidC(encCtx->buffer.input)) + { + return E_INVALID_CONTEXT; + } + + /* Reset output data pointer incase it has been moved */ + _cipherPublishOutput(encCtx, 0, 0); + + switch (encCtx->encArgs.version) + { + case NC_ENC_VERSION_NIP44: + + if ((encCtx->_flags & NC_UTIL_CIPHER_MODE_DECRYPT) > 0) + { + return _nip44DecryptCompleteCore(libContext, sk, pk, encCtx); + } + else + { + /* Ensure the user manually specified a nonce buffer for encryption mode */ + if (!encCtx->encArgs.nonceData) + { + return E_CIPHER_BAD_NONCE; + } + + return _nip44EncryptCompleteCore(libContext, sk, pk, encCtx); + } + + default: + return E_VERSION_NOT_SUPPORTED; + } +} |