Fix numerous log format issues

We had not declared function attributes that check the format syntax;
this led to a number of issues that remained undetected. Fixed.

file_encryption.c

@@ -298,7 +298,7 @@ struct decrypted_file_t read_encrypted_file(const char *filename, passphrase_cal
 		/* Check if the file is long enough to be an encrypted file */
 		const unsigned int encrypted_file_size = statbuf.st_size;
 		if (encrypted_file_size < sizeof(struct encrypted_file_t)) {
-			log_msg(LLVL_ERROR, "%s: too small to be encrypted file (%u bytes)", encrypted_file_size);
+			log_msg(LLVL_ERROR, "%s: too small to be encrypted file (%u bytes)", filename, encrypted_file_size);
 			result.success = false;
 			break;
 		}

keydb.c

@@ -184,7 +184,7 @@ bool keydb_del_host_by_name(struct keydb_t **keydb, const char *host_name) {
 
 	int host_index = keydb_get_host_index(old_keydb, host);
 	if (host_index < 0) {
-		log_msg(LLVL_FATAL, "Fatal error determining host index of \"%s\" for host \"%s\".", host_name);
+		log_msg(LLVL_FATAL, "Fatal error determining host index for hostname \"%s\".", host_name);
 		return false;
 	}
 
@@ -217,7 +217,7 @@ struct volume_entry_t* keydb_add_volume(struct host_entry_t *host, const char *d
 	memcpy(volume->volume_uuid, volume_uuid, 16);
 	strncpy(volume->devmapper_name, devmapper_name, sizeof(volume->devmapper_name) - 1);
 	if (!buffer_randomize(volume->luks_passphrase_raw, sizeof(volume->luks_passphrase_raw))) {
-		log_msg(LLVL_ERROR, "Failed to produce %d bytes of entropy for LUKS passphrase.", sizeof(volume->luks_passphrase_raw));
+		log_msg(LLVL_ERROR, "Failed to produce %ld bytes of entropy for LUKS passphrase.", sizeof(volume->luks_passphrase_raw));
 		return NULL;
 	}
 	host->volume_count++;
@@ -274,14 +274,14 @@ struct keydb_t* keydb_read(const char *filename) {
 
 	struct keydb_t *keydb = (struct keydb_t*)decrypted_file.data;
 	if (keydb->keydb_version != KEYDB_VERSION) {
-		log_msg(LLVL_ERROR, "keydb in %s could be read, but is of version %u (we expected %u).", keydb->keydb_version, KEYDB_VERSION);
+		log_msg(LLVL_ERROR, "keydb in %s could be read, but is of version %u (we expected %u).", filename, keydb->keydb_version, KEYDB_VERSION);
 		OPENSSL_cleanse(decrypted_file.data, decrypted_file.data_length);
 		free(decrypted_file.data);
 		return NULL;
 	}
 
 	if (decrypted_file.data_length != keydb_getsize(keydb)) {
-		log_msg(LLVL_ERROR, "keydb in %s could be read, but was %u bytes long (we expected %u).", decrypted_file.data_length, keydb_getsize(keydb));
+		log_msg(LLVL_ERROR, "keydb in %s could be read, but was %u bytes long (we expected %u).", filename, decrypted_file.data_length, keydb_getsize(keydb));
 		OPENSSL_cleanse(decrypted_file.data, decrypted_file.data_length);
 		free(decrypted_file.data);
 		return NULL;

log.c

@@ -57,7 +57,7 @@ bool should_log(enum loglvl_t level) {
 	return level <= current_loglvl;
 }
 
-void log_msg(enum loglvl_t level, const char *msg, ...) {
+void __attribute__ ((format (printf, 2, 3))) log_msg(enum loglvl_t level, const char *msg, ...) {
 	if (!should_log(level)) {
 		/* Suppress message */
 		return;
@@ -94,7 +94,7 @@ static int log_openssl_error_callback(const char *msg, size_t len, void *vlvlptr
 	truncate_crlf(msgcopy);
 
 	enum loglvl_t* levelptr = (enum loglvl_t*)vlvlptr;
-	log_msg(*levelptr, msgcopy);
+	log_msg(*levelptr, "%s", msgcopy);
 	return 0;
 }
 

log.h

@@ -38,7 +38,7 @@ enum loglvl_t {
 /*************** AUTO GENERATED SECTION FOLLOWS ***************/
 void log_setlvl(enum loglvl_t level);
 bool should_log(enum loglvl_t level);
-void log_msg(enum loglvl_t level, const char *msg, ...);
+void __attribute__ ((format (printf, 2, 3))) log_msg(enum loglvl_t level, const char *msg, ...);
 void log_libc(enum loglvl_t level, const char *msg, ...);
 void log_openssl(enum loglvl_t level, const char *msg, ...);
 /***************  AUTO GENERATED SECTION ENDS   ***************/

server.c

@@ -107,7 +107,7 @@ static int psk_server_callback(SSL *ssl, const unsigned char *identity, size_t i
 	struct client_thread_ctx_t *ctx = (struct client_thread_ctx_t*)SSL_get_app_data(ssl);
 
 	if (identity_len != ASCII_UUID_CHARACTER_COUNT) {
-		log_msg(LLVL_WARNING, "Received client identity of length %d, cannot be a UUID.", identity_len);
+		log_msg(LLVL_WARNING, "Received client identity of length %ld, cannot be a UUID.", identity_len);
 		return 0;
 	}
 
@@ -115,7 +115,7 @@ static int psk_server_callback(SSL *ssl, const unsigned char *identity, size_t i
 	memcpy(uuid_str, identity, ASCII_UUID_CHARACTER_COUNT);
 	uuid_str[ASCII_UUID_CHARACTER_COUNT] = 0;
 	if (!is_valid_uuid(uuid_str)) {
-		log_msg(LLVL_WARNING, "Received client identity of length %d, but not a valid UUID.", identity_len);
+		log_msg(LLVL_WARNING, "Received client identity of length %ld, but not a valid UUID.", identity_len);
 		return 0;
 	}
 
@@ -175,7 +175,7 @@ static void client_handler_thread(void *vctx) {
 				int txlen = SSL_write(ssl, &msgs, sizeof(msgs));
 				OPENSSL_cleanse(&msgs, sizeof(msgs));
 				if (txlen != (long)sizeof(msgs)) {
-					log_msg(LLVL_WARNING, "Tried to send message of %d bytes, but sent %d. Severing connection to client.", sizeof(msgs), txlen);
+					log_msg(LLVL_WARNING, "Tried to send message of %ld bytes, but sent %d. Severing connection to client.", sizeof(msgs), txlen);
 				}
 			} else {
 				log_msg(LLVL_FATAL, "Client connected, but no host set.");