// SPDX-License-Identifier: MIT

// This tests the test vectors published by NIST ACVP


#include <assert.h>
#include <errno.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>

#include <oqs/oqs.h>

#include "system_info.c"

#define RNDBYTES 32

#ifdef OQS_ENABLE_SIG_ml_dsa_44
extern int pqcrystals_ml_dsa_44_ref_signature_internal(uint8_t *sig,
        size_t *siglen,
        const uint8_t *m,
        size_t mlen,
        const uint8_t *pre,
        size_t prelen,
        const uint8_t rnd[RNDBYTES],
        const uint8_t *sk);

extern int pqcrystals_ml_dsa_44_ref_verify_internal(const uint8_t *sig,
        size_t siglen,
        const uint8_t *m,
        size_t mlen,
        const uint8_t *pre,
        size_t prelen,
        const uint8_t *pk);
#endif

#ifdef OQS_ENABLE_SIG_ml_dsa_65
extern int pqcrystals_ml_dsa_65_ref_signature_internal(uint8_t *sig,
        size_t *siglen,
        const uint8_t *m,
        size_t mlen,
        const uint8_t *pre,
        size_t prelen,
        const uint8_t rnd[RNDBYTES],
        const uint8_t *sk);

extern int pqcrystals_ml_dsa_65_ref_verify_internal(const uint8_t *sig,
        size_t siglen,
        const uint8_t *m,
        size_t mlen,
        const uint8_t *pre,
        size_t prelen,
        const uint8_t *pk);
#endif

#ifdef OQS_ENABLE_SIG_ml_dsa_87
extern int pqcrystals_ml_dsa_87_ref_signature_internal(uint8_t *sig,
        size_t *siglen,
        const uint8_t *m,
        size_t mlen,
        const uint8_t *pre,
        size_t prelen,
        const uint8_t rnd[RNDBYTES],
        const uint8_t *sk);

extern int pqcrystals_ml_dsa_87_ref_verify_internal(const uint8_t *sig,
        size_t siglen,
        const uint8_t *m,
        size_t mlen,
        const uint8_t *pre,
        size_t prelen,
        const uint8_t *pk);
#endif

struct {
	const uint8_t *pos;
} prng_state = {
	.pos = 0
};

static void fprintBstr(FILE *fp, const char *S, const uint8_t *A, size_t L) {
	size_t i;
	fprintf(fp, "%s", S);
	for (i = 0; i < L; i++) {
		fprintf(fp, "%02X", A[i]);
	}
	if (L == 0) {
		fprintf(fp, "00");
	}
	fprintf(fp, "\n");
}

static uint8_t hexCharToDecimal(char c) {
	if (c >= '0' && c <= '9') {
		return (uint8_t) (c - '0');
	} else if (c >= 'a' && c <= 'f') {
		return (uint8_t) (c - 'a' + 10);
	} else if (c >= 'A' && c <= 'F') {
		return (uint8_t) (c - 'A' + 10);
	} else {
		fprintf(stderr, "Invalid hex character: %c\n", c);
		return 0;
	}
}

static void hexStringToByteArray(const char *hexString, uint8_t *byteArray) {
	size_t len = strlen(hexString);

	if (len % 2 != 0) {
		fprintf(stderr, "Hex string must have an even number of characters\n");
		exit(EXIT_FAILURE);
	}

	for (size_t i = 0, j = 0; i < len; i += 2, j++) {
		byteArray[j] = (uint8_t) ((hexCharToDecimal(hexString[i]) << 4) | hexCharToDecimal(hexString[i + 1]));
	}
}

/* ML_DSA-specific functions */
static inline bool is_ml_dsa(const char *method_name) {
	return (0 == strcmp(method_name, OQS_SIG_alg_ml_dsa_44))
	       || (0 == strcmp(method_name, OQS_SIG_alg_ml_dsa_65))
	       || (0 == strcmp(method_name, OQS_SIG_alg_ml_dsa_87));
}

static void MLDSA_randombytes_init(const uint8_t *entropy_input, const uint8_t *personalization_string) {
	(void) personalization_string;
	prng_state.pos = entropy_input;
}

static void MLDSA_randombytes(uint8_t *random_array, size_t bytes_to_read) {
	memcpy(random_array, prng_state.pos, bytes_to_read);
	prng_state.pos += bytes_to_read;
}

static void MLDSA_randombytes_free(void) {
	prng_state.pos = 0;
}

static OQS_STATUS sig_kg_vector(const char *method_name,
                                uint8_t *prng_output_stream,
                                const uint8_t *kg_pk, const uint8_t *kg_sk) {
	uint8_t *entropy_input;
	FILE *fh = NULL;
	OQS_SIG *sig = NULL;
	uint8_t *public_key = NULL;
	uint8_t *secret_key = NULL;
	OQS_STATUS rc, ret = OQS_ERROR;

	void (*randombytes_init)(const uint8_t *, const uint8_t *) = NULL;
	void (*randombytes_free)(void) = NULL;

	sig = OQS_SIG_new(method_name);
	if (sig == NULL) {
		printf("[vectors_sig] %s was not enabled at compile-time.\n", method_name);
		goto algo_not_enabled;
	}

	if (is_ml_dsa(method_name)) {
		OQS_randombytes_custom_algorithm(&MLDSA_randombytes);
		randombytes_init = &MLDSA_randombytes_init;
		randombytes_free = &MLDSA_randombytes_free;
		entropy_input = (uint8_t *) prng_output_stream;
	} else {
		// Only ML-DSA supported
		goto err;
	}

	randombytes_init(entropy_input, NULL);

	fh = stdout;

	public_key = OQS_MEM_malloc(sig->length_public_key);
	secret_key = OQS_MEM_malloc(sig->length_secret_key);
	if ((public_key == NULL) || (secret_key == NULL)) {
		fprintf(stderr, "[vectors_sig] %s ERROR: OQS_MEM_malloc failed!\n", method_name);
		goto err;
	}

	if ((prng_output_stream == NULL) || (kg_pk == NULL) || (kg_sk == NULL)) {
		fprintf(stderr, "[vectors_sig] %s ERROR: inputs NULL!\n", method_name);
		goto err;
	}

	rc = OQS_SIG_keypair(sig, public_key, secret_key);
	if (rc) {
		fprintf(stderr, "[vectors_sig] %s ERROR: OQS_SIG_keypair failed!\n", method_name);
		goto err;
	}
	fprintBstr(fh, "pk: ", public_key, sig->length_public_key);
	fprintBstr(fh, "sk: ", secret_key, sig->length_secret_key);

	if (!memcmp(public_key, kg_pk, sig->length_public_key) && !memcmp(secret_key, kg_sk, sig->length_secret_key)) {
		ret = OQS_SUCCESS;
	} else {
		ret = OQS_ERROR;
		fprintf(stderr, "[vectors_sig] %s ERROR: public key or private key doesn't match!\n", method_name);
	}
	goto cleanup;

err:
	ret = OQS_ERROR;
	goto cleanup;

algo_not_enabled:
	ret = OQS_SUCCESS;

cleanup:
	if (sig != NULL) {
		OQS_MEM_secure_free(secret_key, sig->length_secret_key);
	}
	if (randombytes_free != NULL) {
		randombytes_free();
	}
	OQS_MEM_insecure_free(public_key);
	OQS_SIG_free(sig);
	return ret;
}

#if defined(OQS_ENABLE_SIG_ml_dsa_44) || defined(OQS_ENABLE_SIG_ml_dsa_65) || defined(OQS_ENABLE_SIG_ml_dsa_87)
static int sig_ver_vector(const char *method_name,
                          const uint8_t *sigVer_pk_bytes,
                          const uint8_t *sigVer_msg_bytes,
                          size_t msgLen,
                          const uint8_t *sigVer_sig_bytes, int testPassed) {

	FILE *fh = NULL;
	OQS_SIG *sig = NULL;
	int rc = -1, ret = -1;

	sig = OQS_SIG_new(method_name);
	if (sig == NULL) {
		printf("[vectors_sig] %s was not enabled at compile-time.\n", method_name);
		goto algo_not_enabled;
	}

	fh = stdout;

	if ((sigVer_pk_bytes == NULL) || (sigVer_msg_bytes == NULL) || (sigVer_sig_bytes == NULL)) {
		fprintf(stderr, "[vectors_sig] %s ERROR: inputs NULL!\n", method_name);
		goto err;
	}

	if (!strcmp(method_name, "ML-DSA-44")) {
#ifdef OQS_ENABLE_SIG_ml_dsa_44
		rc = pqcrystals_ml_dsa_44_ref_verify_internal(sigVer_sig_bytes, sig->length_signature, sigVer_msg_bytes, msgLen, NULL, 0, sigVer_pk_bytes);
#endif
	} else if (!strcmp(method_name, "ML-DSA-65")) {
#ifdef OQS_ENABLE_SIG_ml_dsa_65
		rc = pqcrystals_ml_dsa_65_ref_verify_internal(sigVer_sig_bytes, sig->length_signature, sigVer_msg_bytes, msgLen, NULL, 0, sigVer_pk_bytes);
#endif
	} else if (!strcmp(method_name, "ML-DSA-87")) {
#ifdef OQS_ENABLE_SIG_ml_dsa_87
		rc = pqcrystals_ml_dsa_87_ref_verify_internal(sigVer_sig_bytes, sig->length_signature, sigVer_msg_bytes, msgLen, NULL, 0, sigVer_pk_bytes);
#endif
	} else {
		goto err;
	}
	if ((!rc) != testPassed) {
		fprintf(stderr, "[vectors_sig] %s ERROR: ml_dsa_verify_internal failed!\n", method_name);
		goto err;
	} else {
		ret = EXIT_SUCCESS;
	}


	fprintBstr(fh, "testPassed: ", (const uint8_t *)&testPassed, 1);

	goto cleanup;

err:
	ret = EXIT_FAILURE;
	goto cleanup;

algo_not_enabled:
	ret = EXIT_SUCCESS;

cleanup:
	OQS_SIG_free(sig);
	return ret;

}

static int sig_gen_vector(const char *method_name,
                          uint8_t *prng_output_stream,
                          const uint8_t *sigGen_sk, const uint8_t *sigGen_msg, size_t sigGen_msgLen, const uint8_t *sigGen_sig) {

	FILE *fh = NULL;
	uint8_t *signature = NULL;
	OQS_SIG *sig = NULL;
	int rc = -1, ret = -1;
	size_t sigLen;

	sig = OQS_SIG_new(method_name);
	if (sig == NULL) {
		printf("[vectors_sig] %s was not enabled at compile-time.\n", method_name);
		goto algo_not_enabled;
	}

	sigLen = sig->length_signature;

	fh = stdout;

	signature = OQS_MEM_malloc(sigLen);

	if (signature == NULL) {
		fprintf(stderr, "[vectors_sig] %s ERROR: OQS_MEM_malloc failed!\n", method_name);
		goto err;
	}

	if ((prng_output_stream == NULL) || (sigGen_sk == NULL) || (sigGen_msg == NULL) || (sigGen_sig == NULL)) {
		fprintf(stderr, "[vectors_sig] %s ERROR: inputs NULL!\n", method_name);
		goto err;
	}

	if (!strcmp(method_name, "ML-DSA-44")) {
#ifdef OQS_ENABLE_SIG_ml_dsa_44
		rc = pqcrystals_ml_dsa_44_ref_signature_internal(signature, &sigLen, sigGen_msg, sigGen_msgLen, NULL, 0, prng_output_stream, sigGen_sk);
#endif
	} else if (!strcmp(method_name, "ML-DSA-65")) {
#ifdef OQS_ENABLE_SIG_ml_dsa_65
		rc = pqcrystals_ml_dsa_65_ref_signature_internal(signature, &sigLen, sigGen_msg, sigGen_msgLen, NULL, 0, prng_output_stream, sigGen_sk);
#endif
	} else if (!strcmp(method_name, "ML-DSA-87")) {
#ifdef OQS_ENABLE_SIG_ml_dsa_87
		rc = pqcrystals_ml_dsa_87_ref_signature_internal(signature, &sigLen, sigGen_msg, sigGen_msgLen, NULL, 0, prng_output_stream, sigGen_sk);
#endif
	} else {
		goto err;
	}

	if (rc) {
		fprintf(stderr, "[vectors_sig] %s ERROR: ml_dsa_sign_internal failed!\n", method_name);
		goto err;
	}
	fprintBstr(fh, "signature: ", signature, sig->length_signature);

	if (!memcmp(signature, sigGen_sig, sigLen)) {
		ret = EXIT_SUCCESS;
	} else {
		ret = EXIT_FAILURE;
		fprintf(stderr, "[vectors_sig] %s ERROR: signature doesn't match!\n", method_name);
	}
	goto cleanup;

err:
	ret = EXIT_FAILURE;
	goto cleanup;

algo_not_enabled:
	ret = EXIT_SUCCESS;

cleanup:
	OQS_MEM_insecure_free(signature);
	OQS_SIG_free(sig);
	return ret;
}
#endif



int main(int argc, char **argv) {
	OQS_STATUS rc = OQS_SUCCESS;
	bool valid_args = true;

	OQS_init();

	size_t msgLen;

	char *prng_output_stream = NULL;
	char *kg_pk;
	char *kg_sk;

	char *sigGen_sk;
	char *sigGen_msg;
	char *sigGen_sig;

	char *sigVer_pk;
	char *sigVer_msg;
	char *sigVer_sig;

	uint8_t *prng_output_stream_bytes = NULL;
	uint8_t *kg_pk_bytes = NULL;
	uint8_t *kg_sk_bytes = NULL;

	uint8_t *sigGen_sk_bytes = NULL;
	uint8_t *sigGen_msg_bytes = NULL;
	uint8_t *sigGen_sig_bytes = NULL;


	uint8_t *sigVer_pk_bytes = NULL;
	uint8_t *sigVer_msg_bytes = NULL;
	uint8_t *sigVer_sig_bytes = NULL;

	OQS_SIG *sig = NULL;

	if (argc < 3) {
		valid_args = false;
		goto err;
	}

	char *alg_name = argv[1];
	char *test_name = argv[2];

	sig = OQS_SIG_new(alg_name);

	if (sig == NULL) {
		printf("[vectors_sig] %s was not enabled at compile-time.\n", alg_name);
		goto err;
	}

	if (!strcmp(test_name, "keyGen")) {
		if (argc != 6) {
			valid_args = false;
			goto err;
		}
		prng_output_stream = argv[3];
		kg_pk = argv[4];
		kg_sk = argv[5];

		if (strlen(prng_output_stream) != 2 * RNDBYTES ||
		        strlen(kg_pk) != 2 * sig->length_public_key ||
		        strlen(kg_sk) != 2 * sig->length_secret_key) {
			printf("lengths bad\n");
			goto err;
		}

		prng_output_stream_bytes = OQS_MEM_malloc(strlen(prng_output_stream) / 2);
		kg_pk_bytes = OQS_MEM_malloc(sig->length_public_key);
		kg_sk_bytes = OQS_MEM_malloc(sig->length_secret_key);

		if ((prng_output_stream_bytes == NULL) || (kg_pk_bytes == NULL) || (kg_sk_bytes == NULL)) {
			fprintf(stderr, "[vectors_sig] ERROR: OQS_MEM_malloc failed!\n");
			goto err;
		}

		hexStringToByteArray(prng_output_stream, prng_output_stream_bytes);
		hexStringToByteArray(kg_pk, kg_pk_bytes);
		hexStringToByteArray(kg_sk, kg_sk_bytes);


		rc = sig_kg_vector(alg_name, prng_output_stream_bytes, kg_pk_bytes, kg_sk_bytes);

	} else if (!strcmp(test_name, "sigGen_det") || !strcmp(test_name, "sigGen_rnd")) {
		int randomized = !strcmp(test_name, "sigGen_rnd");
		if (argc != 6 + randomized) {
			valid_args = false;
			goto err;
		}
		sigGen_sk = argv[3];
		sigGen_msg = argv[4];
		sigGen_sig = argv[5];

		if (randomized) {
			prng_output_stream = argv[6];
			if (strlen(prng_output_stream) != 2 * RNDBYTES) {
				printf("lengths bad\n");
				goto err;
			}
			prng_output_stream_bytes = OQS_MEM_malloc(strlen(prng_output_stream) / 2);
			if (prng_output_stream_bytes == NULL) {
				fprintf(stderr, "[vectors_sig] ERROR: OQS_MEM_malloc failed!\n");
				goto err;
			}
		}

		if ( strlen(sigGen_msg) % 2 != 0 ||
		        strlen(sigGen_sig) != 2 * sig->length_signature) {
			printf("lengths bad\n");
			goto err;
		}

		msgLen = strlen(sigGen_msg) / 2;

		sigGen_sk_bytes = OQS_MEM_malloc(sig->length_secret_key);
		sigGen_msg_bytes = OQS_MEM_malloc(msgLen);
		sigGen_sig_bytes = OQS_MEM_malloc(sig->length_signature);

		if ((sigGen_sk_bytes == NULL) || (sigGen_msg_bytes == NULL) || (sigGen_sig_bytes == NULL)) {
			fprintf(stderr, "[vectors_sig] ERROR: OQS_MEM_malloc failed!\n");
			goto err;
		}

		if (randomized) {
			hexStringToByteArray(prng_output_stream, prng_output_stream_bytes);
		} else {
			prng_output_stream_bytes = OQS_MEM_malloc(RNDBYTES);
			memset(prng_output_stream_bytes, 0, RNDBYTES);
		}


		hexStringToByteArray(sigGen_sk, sigGen_sk_bytes);
		hexStringToByteArray(sigGen_msg, sigGen_msg_bytes);
		hexStringToByteArray(sigGen_sig, sigGen_sig_bytes);

#if defined(OQS_ENABLE_SIG_ml_dsa_44) || defined(OQS_ENABLE_SIG_ml_dsa_65) || defined(OQS_ENABLE_SIG_ml_dsa_87)
		rc = sig_gen_vector(alg_name, prng_output_stream_bytes, sigGen_sk_bytes, sigGen_msg_bytes, msgLen, sigGen_sig_bytes);
#else
		rc = EXIT_SUCCESS;
		goto cleanup;
#endif

	} else if (!strcmp(test_name, "sigVer")) {
		if (argc != 7) {
			valid_args = false;
			goto err;
		}
		sigVer_pk = argv[3];
		sigVer_msg = argv[4];
		sigVer_sig = argv[5];

		int sigVerPassed = atoi(argv[6]);

		if ( strlen(sigVer_msg) % 2 != 0 ||
		        strlen(sigVer_sig) != 2 * sig->length_signature ||
		        strlen(sigVer_pk) != 2 * sig->length_public_key ||
		        (sigVerPassed != 0 && sigVerPassed != 1)) {
			printf("lengths bad or incorrect verification status \n");
			goto err;
		}

		msgLen = strlen(sigVer_msg) / 2;

		sigVer_pk_bytes = OQS_MEM_malloc(sig->length_public_key);
		sigVer_msg_bytes = OQS_MEM_malloc(msgLen);
		sigVer_sig_bytes = OQS_MEM_malloc(sig->length_signature);

		if ((sigVer_pk_bytes == NULL) || (sigVer_msg_bytes == NULL) || (sigVer_sig_bytes == NULL)) {
			fprintf(stderr, "[vectors_sig] ERROR: OQS_MEM_malloc failed!\n");
			goto err;
		}

		hexStringToByteArray(sigVer_pk, sigVer_pk_bytes);
		hexStringToByteArray(sigVer_msg, sigVer_msg_bytes);
		hexStringToByteArray(sigVer_sig, sigVer_sig_bytes);

#if defined(OQS_ENABLE_SIG_ml_dsa_44) || defined(OQS_ENABLE_SIG_ml_dsa_65) || defined(OQS_ENABLE_SIG_ml_dsa_87)
		rc = sig_ver_vector(alg_name, sigVer_pk_bytes, sigVer_msg_bytes, msgLen, sigVer_sig_bytes, sigVerPassed);
#else
		rc = EXIT_SUCCESS;
		goto cleanup;
#endif

	} else {
		printf("[vectors_sig] %s only keyGen/sigGen/sigVer supported!\n", alg_name);
		goto err;
	}
	goto cleanup;

err:
	rc = EXIT_FAILURE;
	if (!valid_args) {
		fprintf(stderr, "Usage: vectors_sig algname testname [testargs]\n");
		fprintf(stderr, "\n");
		printf("\n");
		print_system_info();
	}

cleanup:
	OQS_MEM_insecure_free(prng_output_stream_bytes);
	OQS_MEM_insecure_free(kg_pk_bytes);
	OQS_MEM_insecure_free(kg_sk_bytes);
	OQS_MEM_insecure_free(sigVer_pk_bytes);
	OQS_MEM_insecure_free(sigVer_msg_bytes);
	OQS_MEM_insecure_free(sigVer_sig_bytes);
	OQS_MEM_insecure_free(sigGen_sk_bytes);
	OQS_MEM_insecure_free(sigGen_msg_bytes);
	OQS_MEM_insecure_free(sigGen_sig_bytes);
	OQS_SIG_free(sig);
	OQS_destroy();

	if (rc != EXIT_SUCCESS) {
		return EXIT_FAILURE;
	} else {
		return EXIT_SUCCESS;
	}
}