v0.0.5

7 files changed, 389 insertions, 93 deletions

diff --git a/src/osfp.c b/src/osfp.c
index 87685ba..c629d57 100644
--- a/src/osfp.c
+++ b/src/osfp.c
@@ -33,24 +33,18 @@ static struct osfp_result *osfp_result_build(struct osfp_os_class_score *os_clas
             likely_score = tmp_score;
             likely_os_class = i;
         }
-        result->detail.scores[i] = tmp_score;
+        result->details[i].score = tmp_score;
         sum_score += tmp_score;
     }
 
     if (sum_score) {
         for (i = 0; i < OSFP_OS_CLASS_MAX; i++) {
-            result->detail.possibility[i] = OSFP_PERCENTILE * result->detail.scores[i] / sum_score;
+            result->details[i].possibility = OSFP_PERCENTILE * result->details[i].score / sum_score;
         }
     }
 
-    result->likely_score = likely_score;
-    result->likely_os_class = likely_os_class;
-    result->likely_possibility = result->detail.possibility[likely_os_class];
-
     if (likely_score < OSFP_LOWEST_SCORE_LIMIT) {
-        result->likely_os_class = OSFP_OS_CLASS_OTHERS;
-        result->likely_score = 0;
-        result->likely_possibility = 0;
+        likely_os_class = OSFP_OS_CLASS_OTHERS;
     } else {
         for (i = 0; i < OSFP_OS_CLASS_MAX; i++) {
             if (likely_os_class == i) {
@@ -62,15 +56,15 @@ static struct osfp_result *osfp_result_build(struct osfp_os_class_score *os_clas
                 } else if (likely_os_class == OSFP_OS_CLASS_MAC_OS && i == OSFP_OS_CLASS_IOS) {
                     continue;
                 } else {
-                    result->likely_os_class = OSFP_OS_CLASS_UNKNOWN;
-                    result->likely_score = 0;
-                    result->likely_possibility = 0;
+                    likely_os_class = OSFP_OS_CLASS_UNKNOWN;
                     break;
                 }
             }
         }
     }
 
+    result->likely_os_class = likely_os_class;
+
     return result;
 exit:
     return NULL;
@@ -95,6 +89,7 @@ const char *osfp_result_os_name_get(struct osfp_result *result)
 char *osfp_result_score_detail_export(struct osfp_result *result)
 {
     int i;
+    char *result_str = NULL;
     cJSON *root = NULL;
     cJSON *array;
     cJSON *os_score;
@@ -104,6 +99,7 @@ char *osfp_result_score_detail_export(struct osfp_result *result)
     }
 
     if (result->json_str != NULL) {
+        result_str = result->json_str;
         goto exit;
     }
 
@@ -115,37 +111,35 @@ char *osfp_result_score_detail_export(struct osfp_result *result)
     os_score = cJSON_AddObjectToObject(root, "likely");
     if (os_score) {
         cJSON_AddStringToObject(os_score, "name", osfp_os_class_id_to_name(result->likely_os_class));
-        cJSON_AddNumberToObject(os_score, "score", result->likely_score);
-        //cJSON_AddNumberToObject(os_score, "possibility", result->likely_possibility);
+        cJSON_AddNumberToObject(os_score, "score", result->details[result->likely_os_class].score);
+        //cJSON_AddNumberToObject(os_score, "possibility", result->details[result->likely_os_class].possibility);
     }
 
-    array = cJSON_AddArrayToObject(root, "detail");
+    array = cJSON_AddArrayToObject(root, "details");
     if (array) {
         for (i = OSFP_OS_CLASS_WINDOWS; i < OSFP_OS_CLASS_OTHERS; i++) {
             os_score = cJSON_CreateObject();
             if (os_score) {
                 cJSON_AddStringToObject(os_score, "name", osfp_os_class_id_to_name(i));
-                cJSON_AddNumberToObject(os_score, "score", result->detail.scores[i]);
-                //cJSON_AddNumberToObject(os_score, "possibility", result->detail.possibility[i]);
+                cJSON_AddNumberToObject(os_score, "score", result->details[i].score);
+                //cJSON_AddNumberToObject(os_score, "possibility", result->details[i].possibility);
                 cJSON_AddItemToArray(array, os_score);
             }
         }
     }
 
-    result->json_str = malloc(OSFP_DEFAULT_RESULT_BUFLEN_MAX);
-    if (result->json_str == NULL) {
+    result_str = cJSON_Print(root);
+    if (result_str == NULL) {
         goto exit;
     }
 
-    if (!cJSON_PrintPreallocated(root, result->json_str, OSFP_DEFAULT_RESULT_BUFLEN_MAX, 1)) {
-        goto exit;
-    }
+    result->json_str = result_str;
 
 exit:
     if (root) {
         cJSON_Delete(root);
     }
-    return result->json_str;
+    return result_str;
 }
 
 void osfp_result_free(struct osfp_result *result)
@@ -220,6 +214,37 @@ exit:
     return NULL;
 }
 
+struct osfp_result *osfp_json_identify(struct osfp_db *db, const char *json_str)
+{
+    int ret = OSFP_EINVAL;
+    struct osfp_fingerprint fp;
+    struct osfp_os_class_score os_class_score;
+    struct osfp_result *result;
+
+    if (db == NULL) {
+        goto exit;
+    }
+
+    ret = osfp_fingerprint_from_json(&fp, json_str);
+    if (ret != 0) {
+        goto exit;
+    }
+
+    ret = osfp_score_db_score(db->score_db, 0, &fp, &os_class_score);
+    if (ret != 0) {
+        goto exit;
+    }
+
+    result = osfp_result_build(&os_class_score);
+    if (result == NULL) {
+        goto exit;
+    }
+
+    return result;
+exit:
+    return NULL;
+}
+
 struct osfp_db *osfp_db_new(const char *db_json_file)
 {
     int ret;
diff --git a/src/osfp.h b/src/osfp.h
index 0a4c7e6..660a687 100644
--- a/src/osfp.h
+++ b/src/osfp.h
@@ -8,6 +8,9 @@
 #include <linux/ipv6.h>
 #include <linux/tcp.h>
 
+/**
+ * @brief 定义操作系统类别的名称常量。
+ */
 #define OSFP_OS_CLASS_NAME_UNKNOWN   "Unknown"
 #define OSFP_OS_CLASS_NAME_WINDOWS   "Windows"
 #define OSFP_OS_CLASS_NAME_LINUX     "Linux"
@@ -16,45 +19,112 @@
 #define OSFP_OS_CLASS_NAME_ANDROID   "Android"
 #define OSFP_OS_CLASS_NAME_OTHERS    "Others"
 
+/**
+ * @brief 枚举表示不同的操作系统类别。
+ */
 enum osfp_os_class_id {
-    OSFP_OS_CLASS_UNKNOWN,
-    OSFP_OS_CLASS_WINDOWS,
-    OSFP_OS_CLASS_LINUX,
-    OSFP_OS_CLASS_MAC_OS,
-    OSFP_OS_CLASS_IOS,
-    OSFP_OS_CLASS_ANDROID,
-    OSFP_OS_CLASS_OTHERS,
+    OSFP_OS_CLASS_UNKNOWN,      // 未知
+    OSFP_OS_CLASS_WINDOWS,      // Windows
+    OSFP_OS_CLASS_LINUX,        // Linux
+    OSFP_OS_CLASS_MAC_OS,       // Mac OS
+    OSFP_OS_CLASS_IOS,          // iOS
+    OSFP_OS_CLASS_ANDROID,      // Android
+    OSFP_OS_CLASS_OTHERS,       // 其他
     OSFP_OS_CLASS_MAX,
 };
 
-struct osfp_os_result_detail {
-    unsigned int scores[OSFP_OS_CLASS_MAX];
-    unsigned int possibility[OSFP_OS_CLASS_MAX];
+/**
+ * @brief 结构体用于 osfp_result 中的详细结果。
+ */
+struct osfp_result_detail {
+    unsigned int score;         // 得分
+    unsigned int possibility;   // 可能性
 };
 
+/**
+ * @brief 结构体用于表示操作系统识别结果。
+ */
 struct osfp_result {
-    char *json_str;
-
-    enum osfp_os_class_id   likely_os_class;
-    unsigned int            likely_score;
-    unsigned int            likely_possibility;
-
-    struct osfp_os_result_detail detail;
+    char *json_str;                              // JSON 字符串
+    enum osfp_os_class_id likely_os_class;        // 最可能的操作系统类别
+    struct osfp_result_detail details[OSFP_OS_CLASS_MAX];   // 详细结果数组
 };
 
+/**
+ * @brief 结构体用于表示操作系统指纹库。
+ */
 struct osfp_db {
-    char *db_json_path;
-    void *score_db;
+    char *db_json_path;   // 操作系统指纹库 JSON 文件路径
+    void *score_db;       // 分数数据库指针
 };
 
+/**
+ * @brief 创建一个新的操作系统指纹库。
+ * 
+ * @param db_json_path 操作系统指纹库 JSON 文件的路径。
+ * @return 指向新创建的操作系统指纹库的指针。
+ */
 struct osfp_db *osfp_db_new(const char *db_json_path);
+
+/**
+ * @brief 释放操作系统指纹库占用的内存。
+ * 
+ * @param db 指向要释放的操作系统指纹库的指针。
+ */
 void osfp_db_free(struct osfp_db *db);
 
+/**
+ * @brief 通过 IPv4 头部和 TCP 头部识别操作系统。
+ * 
+ * @param db 操作系统指纹库。
+ * @param l3_hdr 指向 IPv4 头部的指针。
+ * @param l4_hdr 指向 TCP 头部的指针。
+ * @param l4_hdr_len TCP 头部的长度（注意：包含TCP选项部分）。
+ * @return 指向操作系统识别结果的指针。
+ */
 struct osfp_result *osfp_ipv4_identify(struct osfp_db *db, struct iphdr* l3_hdr, struct tcphdr *l4_hdr, size_t l4_hdr_len);
+
+/**
+ * @brief 通过 IPv6 头部和 TCP 头部识别操作系统。
+ * 
+ * @param db 操作系统指纹库。
+ * @param l3_hdr 指向 IPv6 头部的指针。
+ * @param l4_hdr 指向 TCP 头部的指针。
+ * @param l4_hdr_len TCP 头部的长度（注意：包含TCP选项部分）。
+ * @return 指向操作系统识别结果的指针（注意：内存需要使用者释放）。
+ */
 struct osfp_result *osfp_ipv6_identify(struct osfp_db *db, struct ipv6hdr* l3_hdr, struct tcphdr *l4_hdr, size_t l4_hdr_len);
 
+/**
+ * @brief 通过 json 格式的指纹识别操作系统。
+ * 
+ * @param db 操作系统指纹库。
+ * @param json_str 指纹字符串。
+ * @return 指向操作系统识别结果的指针（注意：内存需要使用者释放）。
+ */
+struct osfp_result *osfp_json_identify(struct osfp_db *db, const char *json_str);
+
+/**
+ * @brief 获取操作系统识别结果的操作系统名称。
+ * 
+ * @param result 操作系统识别结果。
+ * @return 指向操作系统名称的常量字符指针（注意：这块内存将由osfp_result_free释放）。
+ */
 const char *osfp_result_os_name_get(struct osfp_result *result);
+
+/**
+ * @brief 导出操作系统识别结果的得分详情。
+ * 
+ * @param result 操作系统识别结果。
+ * @return 指向得分详情字符串的指针（注意：内存需要使用者释放）。
+ */
 char *osfp_result_score_detail_export(struct osfp_result *result);
+
+/**
+ * @brief 释放操作系统识别结果占用的内存。
+ * 
+ * @param result 操作系统识别结果。
+ */
 void osfp_result_free(struct osfp_result *result);
 
 #endif
diff --git a/src/osfp_common.h b/src/osfp_common.h
index 5d1d7bf..12d84a1 100644
--- a/src/osfp_common.h
+++ b/src/osfp_common.h
@@ -84,20 +84,6 @@
 #define OSFP_TCP_OPT_TFO_MIN_LEN                  4  /* kind, len, 2 bytes cookie: 4 */
 #define OSFP_TCP_OPT_TFO_MAX_LEN                  18 /* kind, len, 18 */
 
-
-#define OSFP_WRITE_STRING_TO_BUF(ret, buf, size, off, ...) do {      \
-        ret = snprintf((char *)buf + off,                               \
-                          size - off,                                   \
-                          __VA_ARGS__);                                 \
-        if (ret >= 0) {                                                 \
-            if ( (off + ret) >= size) {                                 \
-                off = size - 1;                                         \
-            } else {                                                    \
-                off += ret;                                             \
-            }                                                           \
-        }                                                               \
-    } while (0)
-
 static inline unsigned long long osfp_rdtsc(void)
 {
 	union {
diff --git a/src/osfp_fingerprint.c b/src/osfp_fingerprint.c
index 8efb6ae..a4551d9 100644
--- a/src/osfp_fingerprint.c
+++ b/src/osfp_fingerprint.c
@@ -40,7 +40,7 @@ struct osfp_fingerprint_field fp_fields[OSFP_FIELD_MAX] = {
     {OSFP_FINGERPRINT_FIELD_NAME_TCP_FLAGS,               1, OSFP_FIELD_TYPE_UINT,    25,     NULL,    0},
     {OSFP_FINGERPRINT_FIELD_NAME_TCP_MSS,                 1, OSFP_FIELD_TYPE_UINT,    150,    NULL,    0},
     {OSFP_FINGERPRINT_FIELD_NAME_TCP_OPTIONS,             1, OSFP_FIELD_TYPE_STRING,  400,    NULL,    0},
-    {OSFP_FINGERPRINT_FIELD_NAME_TCP_OPTIONS_ORDERED,     1, OSFP_FIELD_TYPE_STRING,  250,    NULL,    0},
+    {OSFP_FINGERPRINT_FIELD_NAME_TCP_OPTIONS_ORDERED,     0, OSFP_FIELD_TYPE_STRING,  250,    NULL,    0},
     {OSFP_FINGERPRINT_FIELD_NAME_OS,                      0, OSFP_FIELD_TYPE_STRING,  0,      NULL,    0},
 };
 
@@ -134,6 +134,8 @@ int osfp_fingerprint_to_json_buf(struct osfp_fingerprint *fp, char *strbuf, unsi
         return 0;
     }
 
+    strbuf[0] = 0;
+
     root = cJSON_CreateObject();
     if (root == NULL) {
         return 0;
@@ -165,6 +167,61 @@ int osfp_fingerprint_to_json_buf(struct osfp_fingerprint *fp, char *strbuf, unsi
     return strlen(strbuf) + 1;
 }
 
+int osfp_fingerprint_from_json(struct osfp_fingerprint *fp, char *json_str)
+{
+    int ret, i;
+    cJSON *root;
+    cJSON *field;
+
+    void *value_ptr;
+    unsigned int value_len;
+
+    if (fp == NULL || json_str == NULL) {
+        goto exit;
+    }
+
+    memset(fp, 0, sizeof(struct osfp_fingerprint));
+
+    root = cJSON_Parse(json_str);
+    if (root == NULL) {
+        osfp_log_error("parse json: '%s'\n", json_str);
+        goto exit;
+    }
+
+    for (i = 0; i < OSFP_FIELD_OS; i++) {
+        if (!fp_fields[i].enabled) {
+            continue;
+        }
+    
+        field = cJSON_GetObjectItem(root, osfp_fingerprint_get_field_name(i));
+        if (field == NULL) {
+            goto exit;
+        }
+
+        switch (field->type) {
+            case cJSON_Number:
+                value_ptr = (void *)&field->valueint;
+                value_len = sizeof(field->valueint);
+                osfp_fingerprint_setup_field(fp, i, value_ptr, value_len);
+                break;
+            case cJSON_String:
+                value_ptr = (void *)field->valuestring;
+                value_len = strlen(field->valuestring) + 1;
+                osfp_fingerprint_setup_field(fp, i, value_ptr, value_len);
+                break;
+            case cJSON_NULL:
+                //printf("fingerprint parse error: %s\n%s\n", field->string, cJSON_Print(root));
+                break;
+            default:
+                goto exit;
+        }
+    }
+
+    return 0;
+exit:
+    return ret;
+}
+
 unsigned int osfp_fingerprint_get_field_enabled(enum osfp_field_id field_id)
 {
     return fp_fields[field_id].enabled;
@@ -175,7 +232,7 @@ unsigned int osfp_fingerprint_get_field_importance(enum osfp_field_id field_id)
     return fp_fields[field_id].importance;
 }
 
-char *osfp_fingerprint_get_field_name(enum osfp_field_id field_id)
+const char *osfp_fingerprint_get_field_name(enum osfp_field_id field_id)
 {
     return fp_fields[field_id].name;
 }
@@ -201,7 +258,7 @@ void osfp_fingerprint_setup_field(struct osfp_fingerprint *fp, enum osfp_field_i
     }
 }
 
-void osfp_fingerprinting_tcp_option(unsigned char *opt_data, unsigned int opt_len, struct osfp_fingerprint *fp)
+int osfp_fingerprinting_tcp_option(unsigned char *opt_data, unsigned int opt_len, struct osfp_fingerprint *fp)
 {
     int ret,i;
 
@@ -218,6 +275,10 @@ void osfp_fingerprinting_tcp_option(unsigned char *opt_data, unsigned int opt_le
     unsigned int ordered_offset = 0;
     unsigned int ordered_maxoffset = sizeof(options_ordered) - 1;
 
+    if (opt_data == NULL || opt_len == 0 || fp == NULL) {
+        goto exit;
+    }
+
     tcp_opt_cnt = decode_tcp_options(tcp_opts, OSFP_TCP_OPTMAX, opt_data, opt_len);
 
     for (i = 0; i < tcp_opt_cnt && offset < maxoffset && ordered_offset < ordered_maxoffset; i++) {
@@ -290,7 +351,9 @@ void osfp_fingerprinting_tcp_option(unsigned char *opt_data, unsigned int opt_le
     osfp_fingerprint_setup_field(fp, OSFP_FIELD_TCP_OPTIONS, options, strlen(options) + 1);
     osfp_fingerprint_setup_field(fp, OSFP_FIELD_TCP_OPTIONS_ORDERED, options_ordered, strlen(options_ordered) + 1);
 
-    return;
+    return 0;
+exit:
+    return -1;
 }
 
 int osfp_fingerprinting_tcp(struct tcphdr *tcph, unsigned int tcph_len, struct osfp_fingerprint *fp)
@@ -406,27 +469,27 @@ exit:
 }
 
 #ifdef UNITTEST
-int test_osfp_fingerprinting(void)
+int test_osfp_fingerprinting_ipv4(void)
 {
     int ret;
     char iph[] = {
-      0x45, 0x00, 0x00, 0x34, 0x51, 0xc4, 0x40, 0x00,
-      0x80, 0x06, 0xe7, 0x27, 0xc0, 0xa8, 0x73, 0x08,
-      0x6a, 0xb9, 0x23, 0x6e
+        0x45, 0x00, 0x00, 0x34, 0x51, 0xc4, 0x40, 0x00,
+        0x80, 0x06, 0xe7, 0x27, 0xc0, 0xa8, 0x73, 0x08,
+        0x6a, 0xb9, 0x23, 0x6e
     };
 
     char tcph[] = {
-      0xc1, 0xbd, 0x00, 0x50, 0x3d, 0x58, 0x51, 0x60,
-      0x00, 0x00, 0x00, 0x00, 0x80, 0x02, 0x20, 0x00,
-      0x3d, 0x3a, 0x00, 0x00, 0x02, 0x04, 0x04, 0xec,
-      0x01, 0x03, 0x03, 0x08, 0x01, 0x01, 0x04, 0x02
+        0xc1, 0xbd, 0x00, 0x50, 0x3d, 0x58, 0x51, 0x60,
+        0x00, 0x00, 0x00, 0x00, 0x80, 0x02, 0x20, 0x00,
+        0x3d, 0x3a, 0x00, 0x00, 0x02, 0x04, 0x04, 0xec,
+        0x01, 0x03, 0x03, 0x08, 0x01, 0x01, 0x04, 0x02
     };
 
     char str_buf[2048] = "";
-    const char *target_buf = "{\"ip_id\":1,\"ip_tos\":0,\"ip_total_length\":52,\"ip_ttl\":128,\"tcp_off\":32,\"tcp_timestamp\":null,\"tcp_timestamp_echo_reply\":null,\"tcp_window_scaling\":8,\"tcp_window_size\":8192,\"tcp_flags\":2,\"tcp_mss\":1260,\"tcp_options\":\"M1260,N,W8,N,N,S,\",\"tcp_options_ordered\":\"MNWNNS\",\"os\":\"OSFP_UNKNOWN\"}";
+    const char *target = "{\"ip_id\":1,\"ip_tos\":0,\"ip_total_length\":52,\"ip_ttl\":128,\"tcp_off\":32,\"tcp_timestamp\":null,\"tcp_timestamp_echo_reply\":null,\"tcp_window_scaling\":8,\"tcp_window_size\":8192,\"tcp_flags\":2,\"tcp_mss\":1260,\"tcp_options\":\"M1260,N,W8,N,N,S,\",\"tcp_options_ordered\":\"MNWNNS\",\"os\":\"OSFP_UNKNOWN\"}";
     struct osfp_fingerprint fp = {0};
 
-    ret = osfp_fingerprinting(iph, tcph, &fp);
+    ret = osfp_fingerprinting(iph, tcph, 32, &fp, 4);
     if (ret != 0) {
         goto exit;
     }
@@ -436,7 +499,87 @@ int test_osfp_fingerprinting(void)
         goto exit;
     }
 
-    if (0 != memcmp(str_buf, target_buf, strlen(target_buf))) {
+    if (0 != memcmp(str_buf, target, strlen(target))) {
+        goto exit;
+    }
+
+    return 0;
+exit:
+    return ret;
+}
+
+int test_osfp_fingerprinting_ipv6(void)
+{
+    int ret;
+    char iph[] = {
+        0x45, 0x00, 0x00, 0x34, 0x51, 0xc4, 0x40, 0x00,
+        0x80, 0x06, 0xe7, 0x27, 0xc0, 0xa8, 0x73, 0x08,
+        0x6a, 0xb9, 0x23, 0x6e
+    };
+
+    char tcph[] = {
+        0xc1, 0xbd, 0x00, 0x50, 0x3d, 0x58, 0x51, 0x60,
+        0x00, 0x00, 0x00, 0x00, 0x80, 0x02, 0x20, 0x00,
+        0x3d, 0x3a, 0x00, 0x00, 0x02, 0x04, 0x04, 0xec,
+        0x01, 0x03, 0x03, 0x08, 0x01, 0x01, 0x04, 0x02
+    };
+
+    char str_buf[2048] = "";
+    const char *target = "{\"ip_id\":1,\"ip_tos\":0,\"ip_total_length\":52,\"ip_ttl\":128,\"tcp_off\":32,\"tcp_timestamp\":null,\"tcp_timestamp_echo_reply\":null,\"tcp_window_scaling\":8,\"tcp_window_size\":8192,\"tcp_flags\":2,\"tcp_mss\":1260,\"tcp_options\":\"M1260,N,W8,N,N,S,\",\"tcp_options_ordered\":\"MNWNNS\",\"os\":\"OSFP_UNKNOWN\"}";
+    struct osfp_fingerprint fp = {0};
+
+    ret = osfp_fingerprinting(iph, tcph, 32, &fp, 4);
+    if (ret != 0) {
+        goto exit;
+    }
+
+    ret = osfp_fingerprint_to_json_buf(&fp, str_buf, 2048, 0);
+    if (ret <= 0) {
+        goto exit;
+    }
+
+    if (0 != memcmp(str_buf, target, strlen(target))) {
+        goto exit;
+    }
+
+    return 0;
+exit:
+    return ret;
+}
+
+int test_osfp_fingerprinting_tcp_option(void)
+{
+    int ret;
+    char tcp_opt[] = {
+        0x02, 0x04, 0x04, 0xec,0x01, 0x03, 0x03, 0x08,
+        0x01, 0x01, 0x04, 0x02
+    };
+
+    char str_buf[2048] = "";
+    const char *target_options = "M1260,N,W8,N,N,S,";
+    const char *target_options_ordered = "MNWNNS";
+
+    struct osfp_fingerprint fp = {0};
+
+    ret = osfp_fingerprinting_tcp_option((unsigned char *)tcp_opt, 12, &fp);
+    if (ret != 0) {
+        goto exit;
+    }
+
+    if (fp.fields[OSFP_FIELD_TCP_OPTIONS].value_len != strlen(target_options) + 1)
+    {
+        goto exit;
+    }
+
+    if (0 != memcmp(fp.fields[OSFP_FIELD_TCP_OPTIONS].value, target_options, strlen(target_options) + 1)) {
+        goto exit;
+    }
+
+    if (fp.fields[OSFP_FIELD_TCP_OPTIONS_ORDERED].value_len != strlen(target_options_ordered) + 1) {
+        goto exit;
+    }
+
+    if (0 != memcmp(fp.fields[OSFP_FIELD_TCP_OPTIONS_ORDERED].value, target_options_ordered, strlen(target_options_ordered) + 1)) {
         goto exit;
     }
 
diff --git a/src/osfp_fingerprint.h b/src/osfp_fingerprint.h
index b8838c0..d7c39c8 100644
--- a/src/osfp_fingerprint.h
+++ b/src/osfp_fingerprint.h
@@ -29,7 +29,7 @@ enum osfp_field_type {
 };
 
 struct osfp_fingerprint_field {
-    char            *name;
+    const char      *name;
     unsigned int    enabled;
     unsigned int    type;
     unsigned int    importance;
@@ -43,21 +43,24 @@ struct osfp_fingerprint {
     unsigned int                value_buffer_used;
 };
 
-char *osfp_fingerprint_get_field_name(enum osfp_field_id field_id);
+int osfp_fingerprint_to_json_buf(struct osfp_fingerprint *fp, char *strbuf, unsigned int buf_len, unsigned int format);
+
+void osfp_fingerprint_setup_field(struct osfp_fingerprint *fp, enum osfp_field_id field_id, void *value, unsigned int len);
+
+const char *osfp_fingerprint_get_field_name(enum osfp_field_id field_id);
 unsigned int osfp_fingerprint_get_field_enabled(enum osfp_field_id field_id);
 unsigned int osfp_fingerprint_get_field_importance(enum osfp_field_id field_id);
 unsigned int osfp_fingerprint_get_field_type(enum osfp_field_id field_id);
 
-int osfp_fingerprint_to_json_buf(struct osfp_fingerprint *fp, char *strbuf, unsigned int buf_len, unsigned int format);
-void osfp_fingerprint_setup_field(struct osfp_fingerprint *fp, enum osfp_field_id field_id, void *value, unsigned int len);
-
-void osfp_fingerprinting_tcp_option(unsigned char *pkt, unsigned int pktlen, struct osfp_fingerprint *fp);
+int osfp_fingerprinting_tcp_option(unsigned char *pkt, unsigned int pktlen, struct osfp_fingerprint *fp);
 int osfp_fingerprinting_tcp(struct tcphdr *tcph, unsigned int tcph_len, struct osfp_fingerprint *fp);
 int osfp_fingerprinting_ipv4(struct iphdr *iph, struct osfp_fingerprint *fp);
 int osfp_fingerprinting_ipv6(struct ipv6hdr *iph, struct osfp_fingerprint *fp);
 int osfp_fingerprinting(unsigned char *iph, unsigned char *tcph, unsigned int tcph_len, struct osfp_fingerprint *fp, unsigned int ip_version);
 
 #ifdef UNITTEST
-int test_osfp_fingerprinting(void);
+int test_osfp_fingerprinting_ipv4(void);
+int test_osfp_fingerprinting_ipv6(void);
+int test_osfp_fingerprinting_tcp_option(void);
 #endif
 #endif
diff --git a/src/osfp_score_db.c b/src/osfp_score_db.c
index c5f5d1f..2e38cde 100644
--- a/src/osfp_score_db.c
+++ b/src/osfp_score_db.c
@@ -192,15 +192,6 @@ void osfp_score_db_hash_destroy(void *data) {
     }
 }
 
-struct osfp_os_class_score *osfp_score_db_filed_match(struct osfp_field_score_db *db, void *value, unsigned int len)
-{
-    if (db == NULL || value == NULL || len == 0) {
-        return NULL;
-    }
-
-    return  db->match(db->data, value, len);
-}
-
 char *osfp_score_db_read_file(char *fp_file)
 {
     int ret = -1;
@@ -343,7 +334,7 @@ exit:
 
 int osfp_score_db_load(struct osfp_score_db *score_db, char *fp_file)
 {
-    int ret = OSFP_EINVAL, i;
+    int ret = OSFP_EINVAL, i, count;
     char *file_buffer;
     cJSON *root = NULL;
     cJSON *entry;
@@ -367,9 +358,9 @@ int osfp_score_db_load(struct osfp_score_db *score_db, char *fp_file)
         goto exit;
     }
 
-    score_db->entry_count = cJSON_GetArraySize(root);
+    count = cJSON_GetArraySize(root);
 
-    for (i = 0; i < score_db->entry_count; i++) {
+    for (i = 0; i < count; i++) {
         entry = cJSON_GetArrayItem(root, i);
         if (entry) {
             ret = osfp_score_db_load_entry(score_db, entry);
@@ -377,7 +368,7 @@ int osfp_score_db_load(struct osfp_score_db *score_db, char *fp_file)
                 osfp_log_debug("json entry load failed.\n%s\n", cJSON_Print(entry));
                 continue;
             }
-        } 
+        }
     }
 
     for (i = 0; i < OSFP_FIELD_MAX; i++) {
@@ -437,7 +428,7 @@ int osfp_score_db_score(struct osfp_score_db *score_db, unsigned int flags, stru
             continue;
         }
 
-        os_class_score_matched = osfp_score_db_filed_match(field_score_db, field->value, field->value_len);
+        os_class_score_matched = field_score_db->match(field_score_db->data, field->value, field->value_len);
         if (os_class_score_matched == NULL) {
             continue;
         }
@@ -482,7 +473,6 @@ void osfp_score_db_debug_print(struct osfp_score_db *score_db)
         printf("field %s enabled: %u\n", osfp_fingerprint_get_field_name(i), score_db->field_score_dbs[i].enabled);
         printf("field %s type: %u\n", osfp_fingerprint_get_field_name(i), score_db->field_score_dbs[i].type);
         printf("field %s entry_count: %u\n", osfp_fingerprint_get_field_name(i), score_db->field_score_dbs[i].entry_count);
-        printf("field %s enabled: %u\n", osfp_fingerprint_get_field_name(i), score_db->field_score_dbs[i].data);
     }
 }
 
@@ -556,3 +546,77 @@ void osfp_score_db_destroy(struct osfp_score_db *score_db)
         free(score_db);
     }
 }
+
+#ifdef UNITTEST
+int test_osfp_score_db(void)
+{
+    int ret, i;
+    struct osfp_score_db *db;
+    const char *test_file_path = "./.fp.json";
+    const char *fingerprint_file_content = "["
+        "  {"
+        "    \"tcp_options\": \"M1432,S,T,N,W9,\","
+        "    \"tcp_options_ordered\": \"MSTNW\","
+        "    \"ip_total_length\": 60,"
+        "    \"tcp_off\": 10,"
+        "    \"tcp_window_scaling\": 9,"
+        "    \"tcp_window_size\": 65535,"
+        "    \"ip_ttl\": 64,"
+        "    \"ip_id\": 1,"
+        "    \"tcp_timestamp\": 1,"
+        "    \"tcp_timestamp_echo_reply\": 0,"
+        "    \"tcp_mss\": 1432,"
+        "    \"tcp_flags\": 2,"
+        "    \"ip_tos\": 0,"
+        "    \"os\": \"Android\""
+        "  }"
+        "]";
+
+    db = (void *)osfp_score_db_create();
+    if (db == NULL) {
+        goto exit;
+    }
+
+    FILE *fingerprint_file_ptr = fopen(test_file_path, "w");
+    if (fingerprint_file_ptr == NULL) {
+        goto exit;
+    }
+
+    fprintf(fingerprint_file_ptr, "%s", fingerprint_file_content);
+    fflush(fingerprint_file_ptr);
+    fclose(fingerprint_file_ptr);
+
+    ret = osfp_score_db_load(db, (char *)test_file_path);
+    remove(test_file_path);
+    if (ret != 0) {
+        goto exit;
+    }
+
+    if (db->entry_count != 1) {
+        goto exit;
+    }
+
+    if (db->os_class_entry_count[OSFP_OS_CLASS_ANDROID] != 1) {
+        goto exit;
+    }
+
+    for (i = 0; i < OSFP_FIELD_MAX; i++) {
+        if (db->field_score_dbs[i].enabled != osfp_fingerprint_get_field_enabled(i)) {
+            goto exit;
+        }
+        if (db->field_score_dbs[i].enabled && db->field_score_dbs[i].type != osfp_fingerprint_get_field_type(i)) {
+            goto exit;
+        }
+        if (db->field_score_dbs[i].enabled && db->field_score_dbs[i].entry_count != 1) {
+            goto exit;
+        }
+    }
+
+    osfp_score_db_destroy(db);
+
+    return 0;
+exit:
+    return -1;
+}
+
+#endif
diff --git a/src/osfp_score_db.h b/src/osfp_score_db.h
index cd72467..71b4704 100644
--- a/src/osfp_score_db.h
+++ b/src/osfp_score_db.h
@@ -28,6 +28,7 @@ struct osfp_score_db {
     struct osfp_field_score_db field_score_dbs[OSFP_FIELD_MAX];
 };
 
+char *osfp_score_db_read_file(char *fp_file);
 void osfp_score_db_debug_print(struct osfp_score_db *score_db);
 
 int osfp_score_db_load(struct osfp_score_db *score_db, char *fp_file);
@@ -36,4 +37,8 @@ int osfp_score_db_score(struct osfp_score_db *score_db, unsigned int flags, stru
 struct osfp_score_db *osfp_score_db_create(void);
 void osfp_score_db_destroy(struct osfp_score_db *score_db);
 
+#ifdef UNITTEST
+int test_osfp_score_db(void);
+#endif
+
 #endif