diff --git a/include/ipmitool/helper.h b/include/ipmitool/helper.h
index 98cf459..4d0c785 100644
--- a/include/ipmitool/helper.h
+++ b/include/ipmitool/helper.h
@@ -86,7 +86,7 @@ int str2uchar(const char * str, uint8_t * uchr_ptr);
 int is_fru_id(const char *argv_ptr, uint8_t *fru_id_ptr);
 int is_ipmi_channel_num(const char *argv_ptr, uint8_t *channel_ptr);
 int is_ipmi_user_id(const char *argv_ptr, uint8_t *ipmi_uid_ptr);
-int is_ipmi_user_priv_limit(uint8_t priv_limit);
+int is_ipmi_user_priv_limit(const char *argv_ptr, uint8_t *ipmi_priv_limit_ptr);
 
 uint16_t str2val(const char * str, const struct valstr * vs);
 void print_valstr(const struct valstr * vs, const char * title, int loglevel);
diff --git a/lib/helper.c b/lib/helper.c
index 605f866..2a7ca4c 100644
--- a/lib/helper.c
+++ b/lib/helper.c
@@ -769,13 +769,25 @@ is_ipmi_user_id(const char *argv_ptr, uint8_t *ipmi_uid_ptr)
  * returns (-1) when Priv Limit is invalid
  */
 int
-is_ipmi_user_priv_limit(uint8_t priv_limit)
+is_ipmi_user_priv_limit(const char *argv_ptr, uint8_t *ipmi_priv_limit_ptr)
 {
-	if (0x00 < priv_limit && priv_limit < 0x06 || priv_limit == 0x0f) {
-		return 0;
-	} else {
+	if (!argv_ptr || !ipmi_priv_limit_ptr) {
+		lprintf(LOG_ERR,
+				"is_ipmi_user_priv_limit(): invalid argument(s).");
 		return (-1);
 	}
+	if ((str2uchar(argv_ptr, ipmi_priv_limit_ptr) != 0)
+			|| ((*ipmi_priv_limit_ptr < 0x01
+				|| *ipmi_priv_limit_ptr > 0x05)
+				&& *ipmi_priv_limit_ptr != 0x0F)) {
+		lprintf(LOG_ERR,
+				"Given Privilege Limit '%s' is invalid.",
+				argv_ptr);
+		lprintf(LOG_ERR,
+				"Privilege Limit is limited to <0x1..0x5> and <0xF>.");
+		return (-1);
+	}
+	return 0;
 }
 
 uint16_t
diff --git a/lib/ipmi_channel.c b/lib/ipmi_channel.c
index 450a958..8dcf595 100644
--- a/lib/ipmi_channel.c
+++ b/lib/ipmi_channel.c
@@ -452,13 +452,8 @@ ipmi_set_user_access(struct ipmi_intf * intf, int argc, char ** argv)
 		printf_channel_usage();
 		return 0;
 	}
-
-	if (str2uchar(argv[0], &channel) != 0) {
-		lprintf(LOG_ERR, "Numeric value expected, but '%s' given.", argv[0]);
-		return (-1);
-	}
-	if (str2uchar(argv[1], &userid) != 0) {
-		lprintf(LOG_ERR, "Numeric value expected, but '%s' given.", argv[1]);
+	if (is_ipmi_channel_num(argv[0], &channel) != 0
+			|| is_ipmi_user_id(argv[1], &userid) != 0) {
 		return (-1);
 	}
 
@@ -815,7 +810,6 @@ ipmi_channel_main(struct ipmi_intf *intf, int argc, char **argv)
 	int retval = 0;
 	uint8_t channel;
 	uint8_t priv = 0;
-
 	if (argc < 1) {
 		lprintf(LOG_ERR, "Not enough parameters given.");
 		printf_channel_usage();
@@ -828,69 +822,56 @@ ipmi_channel_main(struct ipmi_intf *intf, int argc, char **argv)
 			printf_channel_usage();
 			return (-1);
 		}
-		/* TODO - validate channel and priv */
-		if (str2uchar(argv[1], &channel) != 0) {
-			lprintf(LOG_ERR, "Numeric value expected, but '%s' given.", argv[1]);
-			return (-1);
-		}
-		if (str2uchar(argv[2], &priv) != 0) {
-			lprintf(LOG_ERR, "Numeric value expected, but '%s' given.", argv[2]);
+		if (is_ipmi_channel_num(argv[1], &channel) != 0
+				|| is_ipmi_user_priv_limit(argv[2], &priv) != 0) {
 			return (-1);
 		}
 		retval = ipmi_get_channel_auth_cap(intf, channel, priv);
 	} else if (strncmp(argv[0], "getaccess", 10) == 0) {
-		uint8_t ch = 0;
-		uint8_t id = 0;
+		uint8_t user_id = 0;
 		if ((argc < 2) || (argc > 3)) {
 			printf_channel_usage();
 			return (-1);
 		}
-		/* TODO - validate channel and uid */
-		if (str2uchar(argv[1], &ch) != 0) {
-			lprintf(LOG_ERR, "Numeric value expected, but '%s' given.", argv[1]);
+		if (is_ipmi_channel_num(argv[1], &channel) != 0) {
 			return (-1);
 		}
 		if (argc == 3) {
-			if (str2uchar(argv[2], &id) != 0) {
-				lprintf(LOG_ERR, "Numeric value expected, but '%s' given.", argv[2]);
+			if (is_ipmi_user_id(argv[2], &user_id) != 0) {
 				return (-1);
 			}
 		}
-		retval = ipmi_get_user_access(intf, ch, id);
+		retval = ipmi_get_user_access(intf, channel, user_id);
 	} else if (strncmp(argv[0], "setaccess", 9) == 0) {
 		retval = ipmi_set_user_access(intf, argc-1, &(argv[1]));
 	} else if (strncmp(argv[0], "info", 4) == 0) {
-		uint8_t ch = 0xe;
+		channel = 0xE;
 		if (argc > 2) {
 			printf_channel_usage();
 			return (-1);
 		}
 		if (argc == 2) {
-			/* TODO - validate channel */
-			if (str2uchar(argv[1], &ch) != 0) {
-				lprintf(LOG_ERR, "Numeric value expected, but '%s' given.", argv[1]);
+			if (is_ipmi_channel_num(argv[1], &channel) != 0) {
 				return (-1);
 			}
 		}
-		retval = ipmi_get_channel_info(intf, ch);
+		retval = ipmi_get_channel_info(intf, channel);
 	} else if (strncmp(argv[0], "getciphers", 10) == 0) {
 		/* channel getciphers <ipmi|sol> [channel] */
-		uint8_t ch = 0xe;
+		channel = 0xE;
 		if ((argc < 2) || (argc > 3) ||
 		    (strncmp(argv[1], "ipmi", 4) && strncmp(argv[1], "sol",  3))) {
 			printf_channel_usage();
 			return (-1);
 		}
 		if (argc == 3) {
-			/* TODO - validate channel */
-			if (str2uchar(argv[2], &ch) != 0) {
-				lprintf(LOG_ERR, "Numeric value expected, but '%s' given.", argv[2]);
+			if (is_ipmi_channel_num(argv[1], &channel) != 0) {
 				return (-1);
 			}
 		}
 		retval = ipmi_get_channel_cipher_suites(intf,
 							argv[1], /* ipmi | sol */
-							ch);
+							channel);
 	} else {
 		printf("Invalid CHANNEL command: %s\n", argv[0]);
 		printf_channel_usage();
diff --git a/lib/ipmi_user.c b/lib/ipmi_user.c
index 635d36c..edc1f86 100644
--- a/lib/ipmi_user.c
+++ b/lib/ipmi_user.c
@@ -559,8 +559,7 @@ ipmi_user_summary(struct ipmi_intf *intf, int argc, char **argv)
 	if (argc == 1) {
 		channel = 0x0E; /* Ask about the current channel */
 	} else if (argc == 2) {
-		if (str2uchar(argv[1], &channel) != 0) {
-			lprintf(LOG_ERR, "Invalid channel: %s", argv[1]);
+		if (is_ipmi_channel_num(argv[1], &channel) != 0) {
 			return (-1);
 		}
 	} else {
@@ -578,8 +577,7 @@ ipmi_user_list(struct ipmi_intf *intf, int argc, char **argv)
 	if (argc == 1) {
 		channel = 0x0E; /* Ask about the current channel */
 	} else if (argc == 2) {
-		if (str2uchar(argv[1], &channel) != 0) {
-			lprintf(LOG_ERR, "Invalid channel: %s", argv[1]);
+		if (is_ipmi_channel_num(argv[1], &channel) != 0) {
 			return (-1);
 		}
 	} else {
@@ -640,18 +638,13 @@ ipmi_user_priv(struct ipmi_intf *intf, int argc, char **argv)
 		return (-1);
 	}
 	if (argc == 4) {
-		if (str2uchar(argv[3], &channel) != 0) {
-			lprintf(LOG_ERR, "Invalid channel: %s", argv[3]);
+		if (is_ipmi_channel_num(argv[3], &channel) != 0) {
 			return (-1);
 		}
 		channel = (channel & 0x0f);
 	}
-	if ((str2uchar(argv[2], &priv_level) != 0)
-			|| is_ipmi_user_priv_limit(priv_level) != 0) {
-		lprintf(LOG_ERR, "Invalid privilege level: %s", argv[2]);
-		return (-1);
-	}
-	if (is_ipmi_user_id(argv[1], &user_id)) {
+	if (is_ipmi_user_priv_limit(argv[2], &priv_level) != 0
+			&& is_ipmi_user_id(argv[1], &user_id)) {
 		return (-1);
 	}
 	priv_level = (priv_level & 0x0f);