/*
 * 模块名称：SHA-256 主机侧单元测试
 * 模块功能：在 PC 上对 App/util/sha256.c 做离线验证（FIPS 180-4 标准向量 +
 *           流式等价 + sha256_hex_eq 边界）。
 *
 * 被测对象：真实源文件 ../../../App/util/sha256.c（以 #include 原样纳入，
 *           保证测的是生产代码而非副本；本模块零平台依赖，无需任何桩）。
 *
 * 为什么要主机侧单测（而不是只靠台架）：
 *   sha256 是 FTP 鉴权的 pwd_hash 校验地基——哈希算错的后果是
 *   "正确口令被拒 / 错误口令放行"这类静默语义错误，板端只看到 530/230，
 *   看不出哪一步坏；标准向量在主机侧毫秒级钉死。
 *
 * 覆盖点：
 *   TC-SHA256-001 FIPS 180-4 向量：空串
 *   TC-SHA256-002 FIPS 180-4 向量："abc"
 *   TC-SHA256-003 FIPS 180-4 向量：56 字节（补位跨分组边界）
 *   TC-SHA256-004 FIPS 180-4 向量：1,000,000 × 'a'（流式，长度字段进第二分组）
 *   TC-SHA256-005 流式任意切分与一次性计算等价（逐字节喂入）
 *   TC-SHA256-006 hex_eq：小写匹配 / 大写匹配
 *   TC-SHA256-007 hex_eq：内容不等 / 非法字符 / 长度 63/65 / NULL → 全 0
 *   TC-SHA256-008 默认口令哈希钉值：SHA256("adminadmin") = FTP_CFG_DEF_HASH 同源值
 *
 * 通过：全部 TC PASS（main 返回 0）。
 * 入口：int main(void)，返回 0=PASS / 1=FAIL（由 run 脚本判读）。
 *
 * 创建日期：2026-10-11
 */

#include <stdio.h>
#include <string.h>

/* 生产源文件原样纳入（零平台依赖，直接编） */
#include "sha256.c"

/* ===================== 断言框架 ===================== */

static int s_total;
static int s_passed;
static int s_failed;

#define CHECK(cond, name) do { \
    s_total++; \
    if (cond) { s_passed++; printf("  PASS %s\n", name); } \
    else { s_failed++; printf("  FAIL %s (line %d)\n", name, __LINE__); } \
} while (0)

/* 摘要 → hex 小写串（仅测试用，允许栈上 sprintf） */
static void digest_to_hex(const uint8_t d[SHA256_DIGEST_SIZE], char out[65])
{
    static const char hexd[] = "0123456789abcdef";

    for (int i = 0; i < 32; i++) {
        out[2 * i]     = hexd[(d[i] >> 4) & 0xF];
        out[2 * i + 1] = hexd[d[i] & 0xF];
    }
    out[64] = '\0';
}

static int hex_eq_vector(const uint8_t d[SHA256_DIGEST_SIZE], const char *want)
{
    char got[65];

    digest_to_hex(d, got);
    return strcmp(got, want) == 0;
}

/* ===================== TC-SHA256-001..004：标准向量 ===================== */

static void tc_vectors(void)
{
    uint8_t d[SHA256_DIGEST_SIZE];

    sha256_calc("", 0u, d);
    CHECK(hex_eq_vector(d, "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"),
          "TC-SHA256-001 empty-string vector");

    sha256_calc("abc", 3u, d);
    CHECK(hex_eq_vector(d, "ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad"),
          "TC-SHA256-002 \"abc\" vector");

    sha256_calc("abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq", 56u, d);
    CHECK(hex_eq_vector(d, "248d6a61d20638b8e5c026930c3e6039a33ce45964ff2167f6ecedd419db06c1"),
          "TC-SHA256-003 56-byte vector (padding crosses block)");

    {
        sha256_ctx_t ctx;

        sha256_init(&ctx);
        for (int i = 0; i < 1000000; i++) {
            sha256_update(&ctx, "a", 1u);
        }
        sha256_final(&ctx, d);
    }
    CHECK(hex_eq_vector(d, "cdc76e5c9914fb9281a1c7e284d73e67f1809a48a497200e046d39ccc7112cd0"),
          "TC-SHA256-004 1e6 x 'a' vector (streaming)");
}

/* ===================== TC-SHA256-005：流式等价 ===================== */

static void tc_stream_equiv(void)
{
    static const char msg[] = "the quick brown fox jumps over the lazy dog";
    uint8_t d1[SHA256_DIGEST_SIZE];
    uint8_t d2[SHA256_DIGEST_SIZE];
    sha256_ctx_t ctx;

    sha256_calc(msg, strlen(msg), d1);
    sha256_init(&ctx);
    for (size_t i = 0; i < strlen(msg); i++) {
        sha256_update(&ctx, &msg[i], 1u);
    }
    sha256_final(&ctx, d2);
    CHECK(memcmp(d1, d2, sizeof(d1)) == 0, "TC-SHA256-005 byte-by-byte feed equals one-shot");
}

/* ===================== TC-SHA256-006..007：hex_eq ===================== */

static void tc_hex_eq(void)
{
    uint8_t d[SHA256_DIGEST_SIZE];
    char lower[65];
    char upper[65];
    char shortv[65];
    char longv[66];

    sha256_calc("adminadmin", 10u, d);
    digest_to_hex(d, lower);
    for (int i = 0; i < 64; i++) {
        upper[i] = (char)((lower[i] >= 'a') ? (lower[i] - 32) : lower[i]);
    }
    upper[64] = '\0';

    CHECK(sha256_hex_eq(d, lower) == 1, "TC-SHA256-006a lowercase hex matches");
    CHECK(sha256_hex_eq(d, upper) == 1, "TC-SHA256-006b uppercase hex matches (case-insensitive)");

    lower[63] = (char)((lower[63] == '0') ? '1' : '0');
    CHECK(sha256_hex_eq(d, lower) == 0, "TC-SHA256-007a content mismatch -> 0");
    lower[63] = (char)((lower[63] == '0') ? '1' : '0');   /* 还原 */

    {
        char bad[65];

        memcpy(bad, lower, 64);
        bad[64] = '\0';
        bad[10] = 'g';
        CHECK(sha256_hex_eq(d, bad) == 0, "TC-SHA256-007b invalid hex char -> 0");
    }

    memcpy(shortv, lower, 63);
    shortv[63] = '\0';
    CHECK(sha256_hex_eq(d, shortv) == 0, "TC-SHA256-007c length 63 -> 0");

    memcpy(longv, lower, 64);
    longv[64] = 'a';
    longv[65] = '\0';
    CHECK(sha256_hex_eq(d, longv) == 0, "TC-SHA256-007d length 65 -> 0");

    CHECK(sha256_hex_eq(d, NULL) == 0, "TC-SHA256-007e NULL -> 0");
}

/* ===================== TC-SHA256-008：默认口令哈希钉值 ===================== */

static void tc_default_hash(void)
{
    uint8_t d[SHA256_DIGEST_SIZE];

    /* 与 ftp_cfg.h FTP_CFG_DEF_HASH 同源钉值（两处若漂移本测试立刻红） */
    sha256_calc("adminadmin", 10u, d);
    CHECK(sha256_hex_eq(d, "d82494f05d6917ba02f7aaa29689ccb444bb73f20380876cb05d1f37537b7892") == 1,
          "TC-SHA256-008 SHA256(\"adminadmin\") = factory default pwd_hash");
}

/* ===================== main ===================== */

int main(void)
{
    printf("=== SHA-256 Tests ===\n");

    printf("-- FIPS 180-4 vectors --\n");
    tc_vectors();
    printf("-- streaming equivalence --\n");
    tc_stream_equiv();
    printf("-- hex_eq --\n");
    tc_hex_eq();
    printf("-- default password hash --\n");
    tc_default_hash();

    printf("\n=== SHA-256 Tests: %d/%d PASSED (failed=%d) ===\n",
           s_passed, s_total, s_failed);
    return (s_failed == 0) ? 0 : 1;
}