Declare return value of getstr() as const char* because the returned strings should not be modifiable. Similarly, neither pack_fixstr() nor pack_str32() should be able to modify strings they are given. Furthermore, getDomainString(), getClientIPString(), getClientNameString(), getSetupVarsArray(), insetupVarsArray(), and getSetupVarsBool() should never modify the strings they receive as arguments.

Signed-off-by: DL6ER <dl6er@dl6er.de>

api.c

@@ -418,8 +418,8 @@ void getTopClients(char *client_message, int *sock)
 		if(strcmp(getstr(clients[j].ippos), HIDDEN_CLIENT) == 0)
 			continue;
 
-		char *client_ip = getstr(clients[j].ippos);
+		const char *client_ip = getstr(clients[j].ippos);
-		char *client_name = getstr(clients[j].namepos);
+		const char *client_name = getstr(clients[j].namepos);
 
 		// Return this client if either
 		// - "withzero" option is set, and/or
@@ -450,12 +450,12 @@ void getTopClients(char *client_message, int *sock)
 void getForwardDestinations(char *client_message, int *sock)
 {
 	bool sort = true;
-	int i, temparray[counters->forwarded][2], totalqueries = 0;
+	int temparray[counters->forwarded][2], totalqueries = 0;
 
 	if(command(client_message, "unsorted"))
 		sort = false;
 
-	for(i=0; i < counters->forwarded; i++) {
+	for(int i = 0; i < counters->forwarded; i++) {
 		validate_access("forwarded", i, true, __LINE__, __FUNCTION__, __FILE__);
 		// If we want to print a sorted output, we fill the temporary array with
 		// the values we will use for sorting afterwards
@@ -474,10 +474,10 @@ void getForwardDestinations(char *client_message, int *sock)
 	totalqueries = counters->forwardedqueries + counters->cached + counters->blocked;
 
 	// Loop over available forward destinations
-	for(i=-2; i < min(counters->forwarded, 8); i++)
+	for(int i = -2; i < min(counters->forwarded, 8); i++)
 	{
-		char *ip, *name;
 		float percentage = 0.0f;
+		const char* ip, *name;
 
 		if(i == -2)
 		{
@@ -797,9 +797,9 @@ void getAllQueries(char *client_message, int *sock)
 
 		// Ask subroutine for domain. It may return "hidden" depending on
 		// the privacy settings at the time the query was made
-		char *domain = getDomainString(i);
+		const char *domain = getDomainString(i);
 		// Similarly for the client
-		char *client;
+		const char *client;
 		if(strlen(getstr(clients[queries[i].clientID].namepos)) > 0)
 			client = getClientNameString(i);
 		else
@@ -844,7 +844,7 @@ void getAllQueries(char *client_message, int *sock)
 
 void getRecentBlocked(char *client_message, int *sock)
 {
-	int i, num=1;
+	int num=1;
 
 	// Test for integer that specifies number of entries to be shown
 	if(sscanf(client_message, "%*[^(](%i)", &num) > 0) {
@@ -855,7 +855,7 @@ void getRecentBlocked(char *client_message, int *sock)
 
 	// Find most recently blocked query
 	int found = 0;
-	for(i = counters->queries - 1; i > 0 ; i--)
+	for(int i = counters->queries - 1; i > 0 ; i--)
 	{
 		validate_access("queries", i, true, __LINE__, __FUNCTION__, __FILE__);
 
@@ -867,7 +867,7 @@ void getRecentBlocked(char *client_message, int *sock)
 
 			// Ask subroutine for domain. It may return "hidden" depending on
 			// the privacy settings at the time the query was made
-			char *domain = getDomainString(i);
+			const char *domain = getDomainString(i);
 
 			if(istelnet[*sock])
 				ssend(*sock,"%s\n", domain);
@@ -1135,8 +1135,8 @@ void getClientNames(int *sock)
 		if(skipclient[i])
 			continue;
 
-		char *client_ip = getstr(clients[i].ippos);
+		const char *client_ip = getstr(clients[i].ippos);
-		char *client_name = getstr(clients[i].namepos);
+		const char *client_name = getstr(clients[i].namepos);
 
 		if(istelnet[*sock])
 			ssend(*sock, "%s %s\n", client_name, client_ip);
@@ -1177,7 +1177,7 @@ void getUnknownQueries(int *sock)
 		validate_access("clients", queries[i].clientID, true, __LINE__, __FUNCTION__, __FILE__);
 
 
-		char *client = getstr(clients[queries[i].clientID].ippos);
+		const char *client = getstr(clients[queries[i].clientID].ippos);
 
 		if(istelnet[*sock])
 			ssend(*sock, "%li %i %i %s %s %s %i %s\n", queries[i].timestamp, i, queries[i].id, type, getstr(domains[queries[i].domainID].domainpos), client, queries[i].status, queries[i].complete ? "true" : "false");

api.h

@@ -39,6 +39,6 @@ void pack_uint64(int sock, uint64_t value);
 void pack_int32(int sock, int32_t value);
 void pack_int64(int sock, int64_t value);
 void pack_float(int sock, float value);
-bool pack_fixstr(int sock, char *string);
+bool pack_fixstr(int sock, const char *string);
-bool pack_str32(int sock, char *string);
+bool pack_str32(int sock, const char *string);
 void pack_map16_start(int sock, uint16_t length);

database.c

@@ -490,11 +490,11 @@ void save_to_DB(void)
 		sqlite3_bind_int(stmt, 3, queries[i].status);
 
 		// DOMAIN
-		char *domain = getDomainString(i);
+		const char *domain = getDomainString(i);
 		sqlite3_bind_text(stmt, 4, domain, -1, SQLITE_TRANSIENT);
 
 		// CLIENT
-		char *client = getClientIPString(i);
+		const char *client = getClientIPString(i);
 		sqlite3_bind_text(stmt, 5, client, -1, SQLITE_TRANSIENT);
 
 		// FORWARD

datastructure.c

@@ -181,7 +181,7 @@ bool isValidIPv6(const char *addr)
 
 // Privacy-level sensitive subroutine that returns the domain name
 // only when appropriate for the requested query
-char *getDomainString(int queryID)
+const char *getDomainString(int queryID)
 {
 	if(queries[queryID].privacylevel < PRIVACY_HIDE_DOMAINS)
 	{
@@ -194,7 +194,7 @@ char *getDomainString(int queryID)
 
 // Privacy-level sensitive subroutine that returns the client IP
 // only when appropriate for the requested query
-char *getClientIPString(int queryID)
+const char *getClientIPString(int queryID)
 {
 	if(queries[queryID].privacylevel < PRIVACY_HIDE_DOMAINS_CLIENTS)
 	{
@@ -207,7 +207,7 @@ char *getClientIPString(int queryID)
 
 // Privacy-level sensitive subroutine that returns the client host name
 // only when appropriate for the requested query
-char *getClientNameString(int queryID)
+const char *getClientNameString(int queryID)
 {
 	if(queries[queryID].privacylevel < PRIVACY_HIDE_DOMAINS_CLIENTS)
 	{

msgpack.c

@@ -75,7 +75,7 @@ void pack_float(int sock, float value) {
 }
 
 // Return true if successful
-bool pack_fixstr(int sock, char *string) {
+bool pack_fixstr(int sock, const char *string) {
 	// Make sure that the length is less than 32
 	size_t length = strlen(string);
 
@@ -86,13 +86,13 @@ bool pack_fixstr(int sock, char *string) {
 
 	uint8_t format = (uint8_t) (0xA0 | length);
 	swrite(sock, &format, sizeof(format));
-	swrite(sock, string, length);
+	swrite(sock, (char*)string, length);
 
 	return true;
 }
 
 // Return true if successful
-bool pack_str32(int sock, char *string) {
+bool pack_str32(int sock, const char *string) {
 	// Make sure that the length is less than 4294967296
 	size_t length = strlen(string);
 
@@ -105,7 +105,7 @@ bool pack_str32(int sock, char *string) {
 	swrite(sock, &format, sizeof(format));
 	uint32_t bigELength = htonl((uint32_t) length);
 	swrite(sock, &bigELength, sizeof(bigELength));
-	swrite(sock, string, length);
+	swrite(sock, (char*)string, length);
 
 	return true;
 }

networktable.c

@@ -123,7 +123,7 @@ void parse_arp_cache(void)
 		bool clientKnown = clientID >= 0;
 
 		// Get hostname of this client if the client is known
-		char *hostname = "";
+		const char *hostname = "";
 		if(clientKnown)
 		{
 			validate_access("clients", clientID, true, __LINE__, __FUNCTION__, __FILE__);

routines.h

@@ -30,9 +30,9 @@ int findDomainID(const char *domain);
 int findClientID(const char *client, bool addNew);
 bool isValidIPv4(const char *addr);
 bool isValidIPv6(const char *addr);
-char *getDomainString(int queryID);
+const char *getDomainString(int queryID);
-char *getClientIPString(int queryID);
+const char *getClientIPString(int queryID);
-char *getClientNameString(int queryID);
+const char *getClientNameString(int queryID);
 
 void close_telnet_socket(void);
 void close_unix_socket(void);
@@ -57,10 +57,10 @@ void check_blocking_status(void);
 
 void check_setupVarsconf(void);
 char * read_setupVarsconf(const char * key);
-void getSetupVarsArray(char * input);
+void getSetupVarsArray(const char * input);
 void clearSetupVarsArray(void);
-bool insetupVarsArray(char * str);
+bool insetupVarsArray(const char * str);
-bool getSetupVarsBool(char * input) __attribute__((pure));
+bool getSetupVarsBool(const char * input) __attribute__((pure));
 
 void parse_args(int argc, char* argv[]);
 
@@ -118,7 +118,7 @@ bool in_whitelist(char *domain) __attribute__((pure));
 bool init_shmem(void);
 void destroy_shmem(void);
 unsigned long long addstr(const char *str);
-char *getstr(unsigned long long pos);
+const char *getstr(unsigned long long pos);
 void *enlarge_shmem_struct(char type);
 
 /**

setupVars.c

@@ -133,9 +133,9 @@ char * read_setupVarsconf(const char * key)
 // setupVarsArray[1] = def
 // setupVarsArray[2] = ghi
 // setupVarsArray[3] = NULL
-void getSetupVarsArray(char * input)
+void getSetupVarsArray(const char * input)
 {
-	char * p = strtok(input, ",");
+	char * p = strtok((char*)input, ",");
 
 	/* split string and append tokens to 'res' */
 
@@ -182,16 +182,15 @@ void clearSetupVarsArray(void)
 	clearSetupVarsArray();
 */
 
-bool insetupVarsArray(char * str)
+bool insetupVarsArray(const char * str)
 {
-	int i;
 	// Check for possible NULL pointer
 	// (this is valid input, e.g. if clients[i].name is unspecified)
 	if(str == NULL)
 		return false;
 
 	// Loop over all entries in setupVarsArray
-	for (i = 0; i < setupVarsElements; ++i)
+	for (int i = 0; i < setupVarsElements; ++i)
 		if(setupVarsArray[i][0] == '*')
 		{
 			// Copying strlen-1 chars into buffer of size strlen: OK
@@ -221,7 +220,7 @@ bool insetupVarsArray(char * str)
 	return false;
 }
 
-bool __attribute__((pure)) getSetupVarsBool(char * input)
+bool __attribute__((pure)) getSetupVarsBool(const char * input)
 {
 	if((strcmp(input, "true")) == 0)
 		return true;

shmem.c

@@ -90,11 +90,11 @@ unsigned long long addstr(const char *str)
 	return (shmSettings->next_str_pos - (len + 1));
 }
 
-char *getstr(unsigned long long pos)
+const char *getstr(unsigned long long pos)
 {
 	// Only access the string memory if this memory region has already been set
 	if(pos < shmSettings->next_str_pos)
-		return &((char*)shm_strings.ptr)[pos];
+		return &((const char*)shm_strings.ptr)[pos];
 	else
 	{
 		logg("WARN: Tried to access %llu but next_str_pos is %u", pos, shmSettings->next_str_pos);