iscsi-scstd: Limit temporary variables to their processing blocks

Move per-address socket variables, parameter-format cursors, netmask
fragments, iSNS read results and Base64 words into the loops or branches
that use them. Preserve operation order and values carried between
iterations. Compute the full initiator name immediately before the kernel
access check instead of nesting the helper call inside that check. Keep
the name buffer, access-check inputs and call order unchanged.

The initiator-name extraction is a readability change found during
source review of the nested call, separate from the variableScope report.

Cppcheck reports variableScope:

  The scope of the variable 'sock' can be reduced.

iscsi-scst/usr/chap.c

@@ -189,7 +189,7 @@ static inline void encode_hex_string(u8 *intnum, long length, char *string)
 /* Base64 encoding, taken from UNH iSCSI "IntegerToBase64String()" */
 static void encode_base64_string(u8 *intnum, long length, char *string)
 {
-	int count, octets, strptr, delta;
+	int count, strptr, delta;
 	static const char base64code[] = { 'A', 'B', 'C', 'D', 'E', 'F', 'G',
 					   'H', 'I', 'J', 'K', 'L', 'M', 'N',
 					   'O', 'P', 'Q', 'R', 'S', 'T', 'U',
@@ -208,6 +208,8 @@ static void encode_base64_string(u8 *intnum, long length, char *string)
 	strptr = 0;
 
 	while ((delta = (length - count)) > 2) {
+		int octets;
+
 		octets = (intnum[count] << 16) | (intnum[count + 1] << 8) | intnum[count + 2];
 		string[strptr] = base64code[(octets & 0xfc0000) >> 18];
 		string[strptr + 1] = base64code[(octets & 0x03f000) >> 12];

iscsi-scst/usr/config.c

@@ -605,7 +605,7 @@ typedef union {
 static int netmask_match_v6(const struct sockaddr_in6 *sa1,
 			    const struct sockaddr_in6 *sa2, uint32_t mbit)
 {
-	uint16_t mask, a1[8], a2[8];
+	uint16_t a1[8], a2[8];
 	int i;
 
 	for (i = 0; i < 8; i++) {
@@ -618,6 +618,8 @@ static int netmask_match_v6(const struct sockaddr_in6 *sa1,
 			return 0;
 
 	if (mbit % 16) {
+		uint16_t mask;
+
 		mask = ~((1 << (16 - (mbit % 16))) - 1);
 		if ((mask & a1[mbit / 16]) ^ (mask & a2[mbit / 16]))
 			return 0;
@@ -1074,11 +1076,11 @@ static int config_isns_load(const char *config)
 {
 	char buf[BUFSIZE];
 	int offset = 0;
-	char *p, *q;
 
 	while (config_gets(buf, sizeof(buf), config, &offset)) {
-		q = buf;
-		p = config_sep_string(&q);
+		char *q = buf;
+		const char *p = config_sep_string(&q);
+
 		if ((*p == '\0') || (*p == '#'))
 			continue;
 		if (!strcasecmp(p, ISCSI_ISNS_SERVER_ATTR_NAME)) {

iscsi-scst/usr/iscsi_adm.c

@@ -247,8 +247,8 @@ out_close:
 
 static void show_iscsi_params(int type, struct iscsi_param *param)
 {
-	int i, nr, len;
-	char buf[1024], *p;
+	int i, nr;
+	char buf[1024];
 	struct iscsi_key *keys;
 
 	if (type == key_session) {
@@ -260,6 +260,9 @@ static void show_iscsi_params(int type, struct iscsi_param *param)
 	}
 
 	for (i = 0; i < nr; i++) {
+		int len;
+		char *p;
+
 		memset(buf, 0, sizeof(buf));
 		iscsi_strscpy(buf, keys[i].name, sizeof(buf));
 		len = strlen(buf);

iscsi-scst/usr/iscsi_scstd.c

@@ -103,7 +103,7 @@ static void create_listen_socket(struct pollfd *array)
 {
 	struct addrinfo hints, *res, *res0;
 	char servname[64];
-	int i, k, sock, opt, rc;
+	int i, k, opt;
 
 	memset(servname, 0, sizeof(servname));
 	snprintf(servname, sizeof(servname), "%d", server_port);
@@ -115,6 +115,7 @@ static void create_listen_socket(struct pollfd *array)
 	i = 0;
 	for (k = 0; k < ADDR_MAX; k++) {
 		char *server_address;
+		int rc;
 
 		server_address = server_addresses[k];
 		if (k > 0 && server_address == NULL)
@@ -133,6 +134,8 @@ static void create_listen_socket(struct pollfd *array)
 		}
 
 		for (res = res0; res && i < LISTEN_MAX; res = res->ai_next) {
+			int sock;
+
 			sock = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
 			if (sock < 0) {
 				log_error("Unable to create server socket (%s) %d %d %d!",
@@ -242,8 +245,7 @@ static void create_iser_listen_socket(struct pollfd *array)
 {
 	struct addrinfo hints, *res, *res0;
 	char servname[64];
-	char *server_address;
-	int rc, i, k;
+	int i, k;
 	int iser_fd;
 	struct isert_addr_info info;
 
@@ -271,6 +273,9 @@ static void create_iser_listen_socket(struct pollfd *array)
 
 	i = 0;
 	for (k = 0; k < ADDR_MAX; k++) {
+		char *server_address;
+		int rc;
+
 		server_address = server_addresses[k];
 
 		if (k > 0 && server_address == NULL)

iscsi-scst/usr/isns.c

@@ -680,9 +680,9 @@ out:
 
 static int recv_hdr(int fd, struct isns_io *rx, struct isns_hdr *hdr)
 {
-	int err;
-
 	if (rx->offset < sizeof(*hdr)) {
+		int err;
+
 		err = read(fd, rx->buf + rx->offset,
 			   sizeof(*hdr) - rx->offset);
 		if (err < 0) {

iscsi-scst/usr/target.c

@@ -164,10 +164,10 @@ int target_portal_allowed(struct target *target,
 			goto out;
 	}
 
-	res = kernel_initiator_allowed(target->tid,
-		iscsi_make_full_initiator_name(target->per_portal_acl,
-			initiator_name, target_portal,
-			full_initiator_name, sizeof(full_initiator_name)));
+	initiator_name = iscsi_make_full_initiator_name(target->per_portal_acl,
+						     initiator_name, target_portal,
+						     full_initiator_name, sizeof(full_initiator_name));
+	res = kernel_initiator_allowed(target->tid, initiator_name);
 	if (res < 0)
 		res = 0; /* false */