/*      $OpenBSD: test_sshbuf_getput_fuzz.c,v 1.7 2026/03/06 06:57:33 dtucker Exp $ */
/*
 * Regress test for sshbuf.h buffer API
 *
 * Placed in the public domain
 */

#include <sys/types.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>

#include <openssl/bn.h>
#include <openssl/ec.h>
#include <openssl/objects.h>

#include "test_helper.h"
#include "ssherr.h"
#include "sshbuf.h"

void sshbuf_getput_fuzz_tests(void);

static void
attempt_parse_blob(u_char *blob, size_t len)
{
        struct sshbuf *p1;
        BIGNUM *bn;
        EC_KEY *eck;
        u_char *s;
        size_t l;
        uint8_t u8;
        uint16_t u16;
        uint32_t u32;
        uint64_t u64;

        p1 = sshbuf_new();
        ASSERT_PTR_NE(p1, NULL);
        ASSERT_INT_EQ(sshbuf_put(p1, blob, len), 0);
        ASSERT_INT_EQ(sshbuf_get_u8(p1, &u8), 0);
        ASSERT_INT_EQ(sshbuf_get_u16(p1, &u16), 0);
        ASSERT_INT_EQ(sshbuf_get_u32(p1, &u32), 0);
        ASSERT_INT_EQ(sshbuf_get_u64(p1, &u64), 0);
        if (sshbuf_get_string(p1, &s, &l) == 0) {
                bzero(s, l);
                free(s);
        }
        bn = NULL;
        ASSERT_INT_EQ(sshbuf_get_bignum2(p1, &bn), 0);
        BN_clear_free(bn);
        eck = EC_KEY_new_by_curve_name(NID_X9_62_prime256v1);
        ASSERT_PTR_NE(eck, NULL);
        ASSERT_INT_EQ(sshbuf_get_eckey(p1, eck), 0);
        EC_KEY_free(eck);
        sshbuf_free(p1);
}


static void
onerror(void *fuzz)
{
        fprintf(stderr, "Failed during fuzz:\n");
        fuzz_dump((struct fuzz *)fuzz);
}

void
sshbuf_getput_fuzz_tests(void)
{
        u_char blob[] = {
                /* u8 */
                0xd0,
                /* u16 */
                0xc0, 0xde,
                /* u32 */
                0xfa, 0xce, 0xde, 0xad,
                /* u64 */
                0xfe, 0xed, 0xac, 0x1d, 0x1f, 0x1c, 0xbe, 0xef,
                /* string */
                0x00, 0x00, 0x00, 0x09,
                'O', ' ', 'G', 'o', 'r', 'g', 'o', 'n', '!',
                /* bignum2 */
                0x00, 0x00, 0x00, 0x14,
                0x00,
                0xf0, 0xe0, 0xd0, 0xc0, 0xb0, 0xa0, 0x90, 0x80,
                0x70, 0x60, 0x50, 0x40, 0x30, 0x20, 0x10, 0x00,
                0x7f, 0xff, 0x11,
                /* EC point (NIST-256 curve) */
                0x00, 0x00, 0x00, 0x41,
                0x04,
                0x0c, 0x82, 0x80, 0x04, 0x83, 0x9d, 0x01, 0x06,
                0xaa, 0x59, 0x57, 0x52, 0x16, 0x19, 0x13, 0x57,
                0x34, 0xb4, 0x51, 0x45, 0x9d, 0xad, 0xb5, 0x86,
                0x67, 0x7e, 0xf9, 0xdf, 0x55, 0x78, 0x49, 0x99,
                0x4d, 0x19, 0x6b, 0x50, 0xf0, 0xb4, 0xe9, 0x4b,
                0x3c, 0x73, 0xe3, 0xa9, 0xd4, 0xcd, 0x9d, 0xf2,
                0xc8, 0xf9, 0xa3, 0x5e, 0x42, 0xbd, 0xd0, 0x47,
                0x55, 0x0f, 0x69, 0xd8, 0x0e, 0xc2, 0x3c, 0xd4,
        };
        struct fuzz *fuzz;
        u_int fuzzers = FUZZ_1_BIT_FLIP | FUZZ_2_BIT_FLIP |
            FUZZ_1_BYTE_FLIP | FUZZ_2_BYTE_FLIP |
            FUZZ_TRUNCATE_START | FUZZ_TRUNCATE_END;

        if (test_is_fast())
                fuzzers &= ~(FUZZ_2_BYTE_FLIP|FUZZ_2_BIT_FLIP);

        TEST_START("fuzz blob parsing");
        fuzz = fuzz_begin(fuzzers, blob, sizeof(blob));
        TEST_ONERROR(onerror, fuzz);
        for(; !fuzz_done(fuzz); fuzz_next(fuzz))
                attempt_parse_blob(blob, sizeof(blob));
        fuzz_cleanup(fuzz);
        TEST_DONE();
        TEST_ONERROR(NULL, NULL);
}