diff --git a/src/common/backend/libpq/md5.cpp b/src/common/backend/libpq/md5.cpp
index 9b8072e0f..f5af86993 100644
--- a/src/common/backend/libpq/md5.cpp
+++ b/src/common/backend/libpq/md5.cpp
@@ -309,6 +309,7 @@ bool pg_md5_encrypt(const char* passwd, const char* salt, size_t salt_len, char*
 {
     size_t passwd_len = strlen(passwd);
     errno_t rc = EOK;
+    /* the length of salt and password is <= SIZE_MAX */
 #ifndef WIN32
     if (unlikely(passwd_len >= SIZE_MAX - salt_len)) {
         return false;
@@ -322,6 +323,7 @@ bool pg_md5_encrypt(const char* passwd, const char* salt, size_t salt_len, char*
     char* crypt_buf = (char*)malloc(passwd_len + salt_len + 1);
     bool ret = false;
 
+    /* the buffer is not exist */
     if (crypt_buf == NULL)
         return false;
 
diff --git a/src/common/backend/libpq/sha2.cpp b/src/common/backend/libpq/sha2.cpp
index 3b996ffe2..484b55c18 100644
--- a/src/common/backend/libpq/sha2.cpp
+++ b/src/common/backend/libpq/sha2.cpp
@@ -772,6 +772,15 @@ bool pg_sha256_encrypt_for_md5(const char* password, const char* salt, size_t sa
     return true;
 }
 
+/*
+ * @Description: calculate the encrypted password for GsSm3.
+ * @const char* password : the password need be encrypted.
+ * @const char* salt_s : the content fo the slat.
+ * @size_t salt_len : the length fo the slat.
+ * @char* buf : the buffer to store the encrypted key with GsSm3.
+ * @char* client_key_buf : the buffer to store the key of client.
+ * @int iteration_count : to record the number of the iteration.
+ */
 bool GsSm3Encrypt(
     const char* password, const char* salt_s, size_t salt_len, char* buf, char* client_key_buf, int iteration_count)
 {
@@ -799,6 +808,7 @@ bool GsSm3Encrypt(
     }
 
     password_len = strlen(password);
+    /* Tranform string(64Bytes) to binary(32Bytes) */
     sha_hex_to_bytes32(salt, (char*)salt_s);
     /* calculate k */
     pkcs_ret = PKCS5_PBKDF2_HMAC((char*)password,
diff --git a/src/gausskernel/optimizer/commands/user.cpp b/src/gausskernel/optimizer/commands/user.cpp
old mode 100755
new mode 100644
index 634d0976d..ae352ad88
--- a/src/gausskernel/optimizer/commands/user.cpp
+++ b/src/gausskernel/optimizer/commands/user.cpp
@@ -5911,6 +5911,7 @@ Datum calculate_encrypted_combined_password(const char* password, const char* ro
     errno_t rc = EOK;
 
     /* For PG ecological compatibility, we stored both sha256 and md5 password. */
+    /* the encrypted method of sha256 */
     if (!pg_sha256_encrypt(password,
             salt_string,
             strlen(salt_string),
@@ -5921,7 +5922,7 @@ Datum calculate_encrypted_combined_password(const char* password, const char* ro
         securec_check(rc, "\0", "\0");
         ereport(ERROR, (errcode(ERRCODE_INVALID_PASSWORD), errmsg("first stage encryption password failed")));
     }
-
+    /* the encrypted method of md5 */
     if (!pg_md5_encrypt(password, rolname, strlen(rolname), encrypted_md5_password)) {
         rc = memset_s(encrypted_md5_password, MD5_PASSWD_LEN + 1, 0, MD5_PASSWD_LEN + 1);
         securec_check(rc, "\0", "\0");
@@ -6052,6 +6053,7 @@ static Datum gs_calculate_encrypted_sm3_password(const char* password, const cha
 Datum calculate_encrypted_password(bool is_encrypted, const char* password, const char* rolname, 
                                    const char* salt_string)
 {
+    /* If the password is '\0' or not exist */
     if (password == NULL || password[0] == '\0') {
         ereport(ERROR, (errcode(ERRCODE_INVALID_PASSWORD), errmsg("The password could not be NULL.")));
     }
@@ -6059,6 +6061,7 @@ Datum calculate_encrypted_password(bool is_encrypted, const char* password, cons
     char encrypted_md5_password[MD5_PASSWD_LEN + 1] = {0};
     Datum datum_value;
 
+    /* If the password has encrypted */
     if (!is_encrypted || isPWDENCRYPTED(password)) {
         return CStringGetTextDatum(password);
     }
@@ -6068,6 +6071,7 @@ Datum calculate_encrypted_password(bool is_encrypted, const char* password, cons
      * if Password_encryption_type is 0, the encrypted password is md5.
      * if Password_encryption_type is 1, the encrypted password is sha256 + md5.
      * if Password_encryption_type is 2, the encrypted password is sha256.
+     * if Password_encryption_type is 3, the encrypted password is SM3.
      */
     if (u_sess->attr.attr_security.Password_encryption_type == 0) {
         if (!pg_md5_encrypt(password, rolname, strlen(rolname), encrypted_md5_password)) {