From 1c475ecb575367a6b3f9328b0f643ad636155341 Mon Sep 17 00:00:00 2001
From: Guus Sliepen <guus@tinc-vpn.org>
Date: Sat, 6 Oct 2018 23:31:05 +0200
Subject: [PATCH] Fix all warnings when compiling with -Wall -W -pedantic.

---
 src/buffer.c                          |  12 +--
 src/buffer.h                          |  14 +--
 src/chacha-poly1305/chacha-poly1305.c |   9 +-
 src/conf.c                            |   4 +-
 src/dummy_device.c                    |   2 +
 src/ed25519/ecdsa.c                   |   4 +-
 src/ed25519/ecdsagen.c                |   3 +-
 src/event.c                           |   2 +
 src/fsck.c                            |   2 +
 src/ifconfig.c                        |   4 +-
 src/info.c                            |   4 +
 src/invitation.c                      |  35 ++++--
 src/invitation.h                      |   1 -
 src/linux/device.c                    |   4 +-
 src/logger.c                          |   5 +-
 src/meta.c                            |  23 ++--
 src/meta.h                            |   6 +-
 src/multicast_device.c                |   2 +-
 src/net.c                             |   2 +-
 src/net.h                             |   6 +-
 src/net_packet.c                      |  42 ++++----
 src/net_setup.c                       |   4 +-
 src/net_socket.c                      |   3 +
 src/netutl.c                          |   2 +-
 src/node.c                            |   6 +-
 src/openssl/crypto.c                  |   4 +-
 src/openssl/prf.c                     |   4 +-
 src/openssl/rsa.c                     |   8 +-
 src/openssl/rsagen.c                  |   2 +
 src/protocol.c                        |   5 +-
 src/protocol_auth.c                   |   6 +-
 src/protocol_edge.c                   |   2 +-
 src/protocol_key.c                    |  13 ++-
 src/protocol_misc.c                   |   4 +
 src/protocol_subnet.c                 |   4 +-
 src/route.c                           |   1 +
 src/splay_tree.c                      |   2 +-
 src/sptps.c                           |  21 +++-
 src/sptps_keypair.c                   |   4 +
 src/sptps_test.c                      |  14 ++-
 src/subnet_parse.c                    |   2 +-
 src/tincctl.c                         | 150 ++++++++++++++++----------
 src/top.c                             |   2 +-
 src/upnp.c                            |   2 +
 src/utils.c                           |  22 ++--
 src/utils.h                           |  10 +-
 46 files changed, 303 insertions(+), 180 deletions(-)

diff --git a/src/buffer.c b/src/buffer.c
index a9e79aa9..60adec86 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -22,7 +22,7 @@
 #include "buffer.h"
 #include "xalloc.h"
 
-void buffer_compact(buffer_t *buffer, int maxsize) {
+void buffer_compact(buffer_t *buffer, uint32_t maxsize) {
 	if(buffer->len >= maxsize || buffer->offset / 7 > buffer->len / 8) {
 		memmove(buffer->data, buffer->data + buffer->offset, buffer->len - buffer->offset);
 		buffer->len -= buffer->offset;
@@ -32,7 +32,7 @@ void buffer_compact(buffer_t *buffer, int maxsize) {
 
 // Make sure we can add size bytes to the buffer, and return a pointer to the start of those bytes.
 
-char *buffer_prepare(buffer_t *buffer, int size) {
+char *buffer_prepare(buffer_t *buffer, uint32_t size) {
 	if(!buffer->data) {
 		buffer->maxlen = size;
 		buffer->data = xmalloc(size);
@@ -58,13 +58,13 @@ char *buffer_prepare(buffer_t *buffer, int size) {
 
 // Copy data into the buffer.
 
-void buffer_add(buffer_t *buffer, const char *data, int size) {
+void buffer_add(buffer_t *buffer, const char *data, uint32_t size) {
 	memcpy(buffer_prepare(buffer, size), data, size);
 }
 
 // Remove given number of bytes from the buffer, return a pointer to the start of them.
 
-static char *buffer_consume(buffer_t *buffer, int size) {
+static char *buffer_consume(buffer_t *buffer, uint32_t size) {
 	char *start = buffer->data + buffer->offset;
 
 	buffer->offset += size;
@@ -86,14 +86,14 @@ char *buffer_readline(buffer_t *buffer) {
 		return NULL;
 	}
 
-	int len = newline + 1 - (buffer->data + buffer->offset);
+	uint32_t len = newline + 1 - (buffer->data + buffer->offset);
 	*newline = 0;
 	return buffer_consume(buffer, len);
 }
 
 // Check if we have enough bytes in the buffer, and if so, return a pointer to the start of them.
 
-char *buffer_read(buffer_t *buffer, int size) {
+char *buffer_read(buffer_t *buffer, uint32_t size) {
 	if(buffer->len - buffer->offset < size) {
 		return NULL;
 	}
diff --git a/src/buffer.h b/src/buffer.h
index 53522b69..b25c8adc 100644
--- a/src/buffer.h
+++ b/src/buffer.h
@@ -3,16 +3,16 @@
 
 typedef struct buffer_t {
 	char *data;
-	int maxlen;
-	int len;
-	int offset;
+	uint32_t maxlen;
+	uint32_t len;
+	uint32_t offset;
 } buffer_t;
 
-extern void buffer_compact(buffer_t *buffer, int maxsize);
-extern char *buffer_prepare(buffer_t *buffer, int size);
-extern void buffer_add(buffer_t *buffer, const char *data, int size);
+extern void buffer_compact(buffer_t *buffer, uint32_t maxsize);
+extern char *buffer_prepare(buffer_t *buffer, uint32_t size);
+extern void buffer_add(buffer_t *buffer, const char *data, uint32_t size);
 extern char *buffer_readline(buffer_t *buffer);
-extern char *buffer_read(buffer_t *buffer, int size);
+extern char *buffer_read(buffer_t *buffer, uint32_t size);
 extern void buffer_clear(buffer_t *buffer);
 
 #endif
diff --git a/src/chacha-poly1305/chacha-poly1305.c b/src/chacha-poly1305/chacha-poly1305.c
index b5dab4e4..a74c5024 100644
--- a/src/chacha-poly1305/chacha-poly1305.c
+++ b/src/chacha-poly1305/chacha-poly1305.c
@@ -20,7 +20,8 @@ void chacha_poly1305_exit(chacha_poly1305_ctx_t *ctx) {
 	free(ctx);
 }
 
-bool chacha_poly1305_set_key(chacha_poly1305_ctx_t *ctx, const void *key) {
+bool chacha_poly1305_set_key(chacha_poly1305_ctx_t *ctx, const void *vkey) {
+	const uint8_t *key = vkey;
 	chacha_keysetup(&ctx->main_ctx, key, 256);
 	chacha_keysetup(&ctx->header_ctx, key + 32, 256);
 	return true;
@@ -39,10 +40,11 @@ static void put_u64(void *vp, uint64_t v) {
 	p[7] = (uint8_t) v & 0xff;
 }
 
-bool chacha_poly1305_encrypt(chacha_poly1305_ctx_t *ctx, uint64_t seqnr, const void *indata, size_t inlen, void *outdata, size_t *outlen) {
+bool chacha_poly1305_encrypt(chacha_poly1305_ctx_t *ctx, uint64_t seqnr, const void *indata, size_t inlen, void *voutdata, size_t *outlen) {
 	uint8_t seqbuf[8];
 	const uint8_t one[8] = { 1, 0, 0, 0, 0, 0, 0, 0 };      /* NB little-endian */
 	uint8_t poly_key[POLY1305_KEYLEN];
+	uint8_t *outdata = voutdata;
 
 	/*
 	 * Run ChaCha20 once to generate the Poly1305 key. The IV is the
@@ -66,10 +68,11 @@ bool chacha_poly1305_encrypt(chacha_poly1305_ctx_t *ctx, uint64_t seqnr, const v
 	return true;
 }
 
-bool chacha_poly1305_decrypt(chacha_poly1305_ctx_t *ctx, uint64_t seqnr, const void *indata, size_t inlen, void *outdata, size_t *outlen) {
+bool chacha_poly1305_decrypt(chacha_poly1305_ctx_t *ctx, uint64_t seqnr, const void *vindata, size_t inlen, void *outdata, size_t *outlen) {
 	uint8_t seqbuf[8];
 	const uint8_t one[8] = { 1, 0, 0, 0, 0, 0, 0, 0 };      /* NB little-endian */
 	uint8_t expected_tag[POLY1305_TAGLEN], poly_key[POLY1305_KEYLEN];
+	const uint8_t *indata = vindata;
 
 	/*
 	 * Run ChaCha20 once to generate the Poly1305 key. The IV is the
diff --git a/src/conf.c b/src/conf.c
index 57065701..0b84ad71 100644
--- a/src/conf.c
+++ b/src/conf.c
@@ -203,7 +203,7 @@ bool get_config_address(const config_t *cfg, struct addrinfo **result) {
 }
 
 bool get_config_subnet(const config_t *cfg, subnet_t **result) {
-	subnet_t subnet = {NULL};
+	subnet_t subnet = {0};
 
 	if(!cfg) {
 		return false;
@@ -433,7 +433,7 @@ bool read_server_config(void) {
 
 				// And we try to read the ones that end with ".conf"
 				if(l > 5 && !strcmp(".conf", & ep->d_name[ l - 5 ])) {
-					if(snprintf(fname, sizeof(fname), "%s" SLASH "%s", dname, ep->d_name) >= sizeof(fname)) {
+					if((size_t)snprintf(fname, sizeof(fname), "%s" SLASH "%s", dname, ep->d_name) >= sizeof(fname)) {
 						logger(DEBUG_ALWAYS, LOG_ERR, "Pathname too long: %s/%s", dname, ep->d_name);
 						return false;
 					}
diff --git a/src/dummy_device.c b/src/dummy_device.c
index 80232e1e..15f0654f 100644
--- a/src/dummy_device.c
+++ b/src/dummy_device.c
@@ -37,10 +37,12 @@ static void close_device(void) {
 }
 
 static bool read_packet(vpn_packet_t *packet) {
+	(void)packet;
 	return false;
 }
 
 static bool write_packet(vpn_packet_t *packet) {
+	(void)packet;
 	return true;
 }
 
diff --git a/src/ed25519/ecdsa.c b/src/ed25519/ecdsa.c
index 79532c8f..4bd71556 100644
--- a/src/ed25519/ecdsa.c
+++ b/src/ed25519/ecdsa.c
@@ -63,10 +63,11 @@ char *ecdsa_get_base64_public_key(ecdsa_t *ecdsa) {
 
 // Read PEM ECDSA keys
 
-static bool read_pem(FILE *fp, const char *type, void *buf, size_t size) {
+static bool read_pem(FILE *fp, const char *type, void *vbuf, size_t size) {
 	char line[1024];
 	bool data = false;
 	size_t typelen = strlen(type);
+	char *buf = vbuf;
 
 	while(fgets(line, sizeof(line), fp)) {
 		if(!data) {
@@ -143,6 +144,7 @@ ecdsa_t *ecdsa_read_pem_private_key(FILE *fp) {
 }
 
 size_t ecdsa_size(ecdsa_t *ecdsa) {
+	(void)ecdsa;
 	return 64;
 }
 
diff --git a/src/ed25519/ecdsagen.c b/src/ed25519/ecdsagen.c
index 9a1de1e7..ede51367 100644
--- a/src/ed25519/ecdsagen.c
+++ b/src/ed25519/ecdsagen.c
@@ -46,9 +46,10 @@ ecdsa_t *ecdsa_generate(void) {
 
 // Write PEM ECDSA keys
 
-static bool write_pem(FILE *fp, const char *type, void *buf, size_t size) {
+static bool write_pem(FILE *fp, const char *type, void *vbuf, size_t size) {
 	fprintf(fp, "-----BEGIN %s-----\n", type);
 
+	char *buf = vbuf;
 	char base64[65];
 
 	while(size) {
diff --git a/src/event.c b/src/event.c
index 8c7de479..47adb181 100644
--- a/src/event.c
+++ b/src/event.c
@@ -237,6 +237,8 @@ static void signal_handler(int signum) {
 }
 
 static void signalio_handler(void *data, int flags) {
+	(void)data;
+	(void)flags;
 	unsigned char signum;
 
 	if(read(pipefd[0], &signum, 1) != 1) {
diff --git a/src/fsck.c b/src/fsck.c
index e17b46c5..e19f03ff 100644
--- a/src/fsck.c
+++ b/src/fsck.c
@@ -88,6 +88,8 @@ static int strtailcmp(const char *str, const char *tail) {
 }
 
 static void check_conffile(const char *fname, bool server) {
+	(void)server;
+
 	FILE *f = fopen(fname, "r");
 
 	if(!f) {
diff --git a/src/ifconfig.c b/src/ifconfig.c
index 3723c97a..4b47ad13 100644
--- a/src/ifconfig.c
+++ b/src/ifconfig.c
@@ -86,7 +86,7 @@ bool ifconfig_footer(FILE *out) {
 static subnet_t ipv4, ipv6;
 
 void ifconfig_address(FILE *out, const char *value) {
-	subnet_t address = {NULL};
+	subnet_t address = {0};
 	char address_str[MAXNETSTR];
 
 	if(!str2net(&address, value) || !net2str(address_str, sizeof(address_str), &address)) {
@@ -168,7 +168,7 @@ void ifconfig_address(FILE *out, const char *value) {
 }
 
 void ifconfig_route(FILE *out, const char *value) {
-	subnet_t subnet = {NULL}, gateway = {NULL};
+	subnet_t subnet = {0}, gateway = {0};
 	char subnet_str[MAXNETSTR] = "", gateway_str[MAXNETSTR] = "";
 	char *sep = strchr(value, ' ');
 
diff --git a/src/info.c b/src/info.c
index 562b5ff2..758c0d1f 100644
--- a/src/info.c
+++ b/src/info.c
@@ -28,10 +28,14 @@
 #include "xalloc.h"
 
 void logger(int level, int priority, const char *format, ...) {
+	(void)level;
+	(void)priority;
 	va_list ap;
+
 	va_start(ap, format);
 	vfprintf(stderr, format, ap);
 	va_end(ap);
+
 	fputc('\n', stderr);
 }
 
diff --git a/src/invitation.c b/src/invitation.c
index c3072cf2..500f2434 100644
--- a/src/invitation.c
+++ b/src/invitation.c
@@ -356,7 +356,7 @@ int cmd_invite(int argc, char *argv[]) {
 		char invname[PATH_MAX];
 		struct stat st;
 
-		if(snprintf(invname, sizeof(invname), "%s" SLASH "%s", filename, ent->d_name) >= sizeof(invname)) {
+		if((size_t)snprintf(invname, sizeof(invname), "%s" SLASH "%s", filename, ent->d_name) >= sizeof(invname)) {
 			fprintf(stderr, "Filename too long: %s" SLASH "%s\n", filename, ent->d_name);
 			continue;
 		}
@@ -555,7 +555,7 @@ static char *get_line(const char **data) {
 
 	static char line[1024];
 	const char *end = strchr(*data, '\n');
-	size_t len = end ? end - *data : strlen(*data);
+	size_t len = end ? (size_t)(end - *data) : strlen(*data);
 
 	if(len >= sizeof(line)) {
 		fprintf(stderr, "Maximum line length exceeded!\n");
@@ -635,7 +635,7 @@ static char *grep(const char *data, const char *var) {
 		return xstrdup(p);
 	}
 
-	if(e - p >= sizeof(value)) {
+	if((size_t)(e - p) >= sizeof(value)) {
 		fprintf(stderr, "Maximum line length exceeded!\n");
 		return NULL;
 	}
@@ -646,13 +646,18 @@ static char *grep(const char *data, const char *var) {
 }
 
 static bool finalize_join(void) {
-	const char *name = get_value(data, "Name");
+	const char *temp_name = get_value(data, "Name");
 
-	if(!name) {
+	if(!temp_name) {
 		fprintf(stderr, "No Name found in invitation!\n");
 		return false;
 	}
 
+	size_t len = strlen(temp_name);
+	char name[len + 1];
+	memcpy(name, temp_name, len);
+	name[len] = 0;
+
 	if(!check_id(name)) {
 		fprintf(stderr, "Invalid Name found in invitation!\n");
 		return false;
@@ -962,7 +967,7 @@ ask_netname:
 
 		char newbase[PATH_MAX];
 
-		if(snprintf(newbase, sizeof(newbase), CONFDIR SLASH "tinc" SLASH "%s", line) >= sizeof(newbase)) {
+		if((size_t)snprintf(newbase, sizeof(newbase), CONFDIR SLASH "tinc" SLASH "%s", line) >= sizeof(newbase)) {
 			fprintf(stderr, "Filename too long: " CONFDIR SLASH "tinc" SLASH "%s\n", line);
 			goto ask_netname;
 		}
@@ -1007,7 +1012,13 @@ ask_netname:
 				if(response == 'e') {
 					char *command;
 #ifndef HAVE_MINGW
-					xasprintf(&command, "\"%s\" \"%s\"", getenv("VISUAL") ? : getenv("EDITOR") ? : "vi", filename);
+					const char *editor = getenv("VISUAL");
+					if (!editor)
+						editor = getenv("EDITOR");
+					if (!editor)
+						editor = "vi";
+
+					xasprintf(&command, "\"%s\" \"%s\"", editor, filename);
 #else
 					xasprintf(&command, "edit \"%s\"", filename);
 #endif
@@ -1044,7 +1055,11 @@ ask_netname:
 }
 
 
-static bool invitation_send(void *handle, uint8_t type, const void *data, size_t len) {
+static bool invitation_send(void *handle, uint8_t type, const void *vdata, size_t len) {
+	(void)handle;
+	(void)type;
+	const char *data = vdata;
+
 	while(len) {
 		int result = send(sock, data, len, 0);
 
@@ -1062,6 +1077,8 @@ static bool invitation_send(void *handle, uint8_t type, const void *data, size_t
 }
 
 static bool invitation_receive(void *handle, uint8_t type, const void *msg, uint16_t len) {
+	(void)handle;
+
 	switch(type) {
 	case SPTPS_HANDSHAKE:
 		return sptps_send_record(&sptps, 0, cookie, sizeof(cookie));
@@ -1240,7 +1257,7 @@ next:
 	// Tell him we have an invitation, and give him our throw-away key.
 	int len = snprintf(line, sizeof(line), "0 ?%s %d.%d\n", b64key, PROT_MAJOR, PROT_MINOR);
 
-	if(len <= 0 || len >= sizeof(line)) {
+	if(len <= 0 || (size_t)len >= sizeof(line)) {
 		abort();
 	}
 
diff --git a/src/invitation.h b/src/invitation.h
index 621baab9..6517fe84 100644
--- a/src/invitation.h
+++ b/src/invitation.h
@@ -20,7 +20,6 @@
     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
 
-bool recvdata(int fd, char *data, size_t len);
 int cmd_invite(int argc, char *argv[]);
 int cmd_join(int argc, char *argv[]);
 
diff --git a/src/linux/device.c b/src/linux/device.c
index 0abafa9d..94e223f7 100644
--- a/src/linux/device.c
+++ b/src/linux/device.c
@@ -67,7 +67,7 @@ static bool setup_device(void) {
 	fcntl(device_fd, F_SETFD, FD_CLOEXEC);
 #endif
 
-	struct ifreq ifr = {{{0}}};
+	struct ifreq ifr = {0};
 
 	get_config_string(lookup_config(config_tree, "DeviceType"), &type);
 
@@ -119,7 +119,7 @@ static bool setup_device(void) {
 	logger(DEBUG_ALWAYS, LOG_INFO, "%s is a %s", device, device_info);
 
 	if(ifr.ifr_flags & IFF_TAP) {
-		struct ifreq ifr_mac = {{{0}}};
+		struct ifreq ifr_mac = {0};
 
 		if(!ioctl(device_fd, SIOCGIFHWADDR, &ifr_mac)) {
 			memcpy(mymac.x, ifr_mac.ifr_hwaddr.sa_data, ETH_ALEN);
diff --git a/src/logger.c b/src/logger.c
index bcadae11..062f7598 100644
--- a/src/logger.c
+++ b/src/logger.c
@@ -130,7 +130,7 @@ void logger(int level, int priority, const char *format, ...) {
 	message[sizeof(message) - 1] = 0;
 	va_end(ap);
 
-	if(len > 0 && len < sizeof(message) - 1 && message[len - 1] == '\n') {
+	if(len > 0 && (size_t)len < sizeof(message) - 1 && message[len - 1] == '\n') {
 		message[len - 1] = 0;
 	}
 
@@ -138,13 +138,14 @@ void logger(int level, int priority, const char *format, ...) {
 }
 
 static void sptps_logger(sptps_t *s, int s_errno, const char *format, va_list ap) {
+	(void)s_errno;
 	char message[1024];
 	size_t msglen = sizeof(message);
 
 	int len = vsnprintf(message, msglen, format, ap);
 	message[sizeof(message) - 1] = 0;
 
-	if(len > 0 && len < sizeof(message) - 1) {
+	if(len > 0 && (size_t)len < sizeof(message) - 1) {
 		if(message[len - 1] == '\n') {
 			message[--len] = 0;
 		}
diff --git a/src/meta.c b/src/meta.c
index 5b47aa66..0089ac82 100644
--- a/src/meta.c
+++ b/src/meta.c
@@ -35,6 +35,7 @@
 #endif
 
 bool send_meta_sptps(void *handle, uint8_t type, const void *buffer, size_t length) {
+	(void)type;
 	connection_t *c = handle;
 
 	if(!c) {
@@ -48,13 +49,13 @@ bool send_meta_sptps(void *handle, uint8_t type, const void *buffer, size_t leng
 	return true;
 }
 
-bool send_meta(connection_t *c, const char *buffer, int length) {
+bool send_meta(connection_t *c, const char *buffer, size_t length) {
 	if(!c) {
 		logger(DEBUG_ALWAYS, LOG_ERR, "send_meta() called with NULL pointer!");
 		abort();
 	}
 
-	logger(DEBUG_META, LOG_DEBUG, "Sending %d bytes of metadata to %s (%s)", length,
+	logger(DEBUG_META, LOG_DEBUG, "Sending %lu bytes of metadata to %s (%s)", (unsigned long)length,
 	       c->name, c->hostname);
 
 	if(c->protocol_minor >= 2) {
@@ -92,13 +93,13 @@ bool send_meta(connection_t *c, const char *buffer, int length) {
 	return true;
 }
 
-void send_meta_raw(connection_t *c, const char *buffer, int length) {
+void send_meta_raw(connection_t *c, const char *buffer, size_t length) {
 	if(!c) {
 		logger(DEBUG_ALWAYS, LOG_ERR, "send_meta() called with NULL pointer!");
 		abort();
 	}
 
-	logger(DEBUG_META, LOG_DEBUG, "Sending %d bytes of raw metadata to %s (%s)", length,
+	logger(DEBUG_META, LOG_DEBUG, "Sending %lu bytes of raw metadata to %s (%s)", (unsigned long)length,
 	       c->name, c->hostname);
 
 	buffer_add(&c->outbuf, buffer, length);
@@ -106,7 +107,7 @@ void send_meta_raw(connection_t *c, const char *buffer, int length) {
 	io_set(&c->io, IO_READ | IO_WRITE);
 }
 
-void broadcast_meta(connection_t *from, const char *buffer, int length) {
+void broadcast_meta(connection_t *from, const char *buffer, size_t length) {
 	for list_each(connection_t, c, connection_list)
 		if(c != from && c->edge) {
 			send_meta(c, buffer, length);
@@ -158,7 +159,7 @@ bool receive_meta_sptps(void *handle, uint8_t type, const void *vdata, uint16_t
 }
 
 bool receive_meta(connection_t *c) {
-	int inlen;
+	ssize_t inlen;
 	char inbuf[MAXBUFSIZE];
 	char *bufp = inbuf, *endp;
 
@@ -197,7 +198,7 @@ bool receive_meta(connection_t *c) {
 		/* Are we receiving a SPTPS packet? */
 
 		if(c->sptpslen) {
-			int len = MIN(inlen, c->sptpslen - c->inbuf.len);
+			ssize_t len = MIN(inlen, c->sptpslen - c->inbuf.len);
 			buffer_add(&c->inbuf, bufp, len);
 
 			char *sptpspacket = buffer_read(&c->inbuf, c->sptpslen);
@@ -218,7 +219,7 @@ bool receive_meta(connection_t *c) {
 		}
 
 		if(c->protocol_minor >= 2) {
-			int len = sptps_receive_data(&c->sptps, bufp, inlen);
+			size_t len = sptps_receive_data(&c->sptps, bufp, inlen);
 
 			if(!len) {
 				return false;
@@ -247,8 +248,8 @@ bool receive_meta(connection_t *c) {
 			return false;
 #else
 
-			if(inlen > c->inbudget) {
-				logger(DEBUG_META, LOG_ERR, "yte limit exceeded for decryption from %s (%s)", c->name, c->hostname);
+			if((size_t)inlen > c->inbudget) {
+				logger(DEBUG_META, LOG_ERR, "Byte limit exceeded for decryption from %s (%s)", c->name, c->hostname);
 				return false;
 			} else {
 				c->inbudget -= inlen;
@@ -256,7 +257,7 @@ bool receive_meta(connection_t *c) {
 
 			size_t outlen = inlen;
 
-			if(!cipher_decrypt(c->incipher, bufp, inlen, buffer_prepare(&c->inbuf, inlen), &outlen, false) || inlen != outlen) {
+			if(!cipher_decrypt(c->incipher, bufp, inlen, buffer_prepare(&c->inbuf, inlen), &outlen, false) || (size_t)inlen != outlen) {
 				logger(DEBUG_ALWAYS, LOG_ERR, "Error while decrypting metadata from %s (%s)",
 				       c->name, c->hostname);
 				return false;
diff --git a/src/meta.h b/src/meta.h
index 1c134ff1..dcf2419b 100644
--- a/src/meta.h
+++ b/src/meta.h
@@ -23,11 +23,11 @@
 
 #include "connection.h"
 
-extern bool send_meta(struct connection_t *c, const char *buffer, int length);
-extern void send_meta_raw(struct connection_t *c, const char *buffer, int length);
+extern bool send_meta(struct connection_t *c, const char *buffer, size_t length);
+extern void send_meta_raw(struct connection_t *c, const char *buffer, size_t length);
 extern bool send_meta_sptps(void *handle, uint8_t type, const void *data, size_t length);
 extern bool receive_meta_sptps(void *handle, uint8_t type, const void *data, uint16_t length);
-extern void broadcast_meta(struct connection_t *from, const char *buffer, int length);
+extern void broadcast_meta(struct connection_t *from, const char *buffer, size_t length);
 extern bool receive_meta(struct connection_t *c);
 
 #endif
diff --git a/src/multicast_device.c b/src/multicast_device.c
index 99f26ca9..e9607f0d 100644
--- a/src/multicast_device.c
+++ b/src/multicast_device.c
@@ -32,7 +32,7 @@
 static const char *device_info = "multicast socket";
 
 static struct addrinfo *ai = NULL;
-static mac_t ignore_src = {{0}};
+static mac_t ignore_src = {0};
 
 static bool setup_device(void) {
 	char *host = NULL;
diff --git a/src/net.c b/src/net.c
index e9aed34c..75838e00 100644
--- a/src/net.c
+++ b/src/net.c
@@ -95,7 +95,7 @@ void purge(void) {
 /* Put a misbehaving connection in the tarpit */
 void tarpit(int fd) {
 	static int pits[10] = {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1};
-	static int next_pit = 0;
+	static unsigned int next_pit = 0;
 
 	if(pits[next_pit] != -1) {
 		closesocket(pits[next_pit]);
diff --git a/src/net.h b/src/net.h
index aaf29b6f..8a74d859 100644
--- a/src/net.h
+++ b/src/net.h
@@ -56,7 +56,7 @@ typedef struct node_id_t {
 	uint8_t x[6];
 } node_id_t;
 
-typedef short length_t;
+typedef uint16_t length_t;
 typedef uint32_t seqno_t;
 
 #define AF_UNKNOWN 255
@@ -190,8 +190,8 @@ extern int setup_vpn_in_socket(const sockaddr_t *sa);
 extern bool send_sptps_data(node_t *to, node_t *from, int type, const void *data, size_t len);
 extern bool receive_sptps_record(void *handle, uint8_t type, const void *data, uint16_t len);
 extern void send_packet(struct node_t *n, vpn_packet_t *packet);
-extern void receive_tcppacket(struct connection_t *c, const char *buffer, int length);
-extern bool receive_tcppacket_sptps(struct connection_t *c, const char *buffer, int length);
+extern void receive_tcppacket(struct connection_t *c, const char *buffer, size_t length);
+extern bool receive_tcppacket_sptps(struct connection_t *c, const char *buffer, size_t length);
 extern void broadcast_packet(const struct node_t *n, vpn_packet_t *packet);
 extern char *get_name(void);
 extern void device_enable(void);
diff --git a/src/net_packet.c b/src/net_packet.c
index a516b4a9..6b40f2ad 100644
--- a/src/net_packet.c
+++ b/src/net_packet.c
@@ -216,7 +216,7 @@ static length_t compress_packet(uint8_t *dest, const uint8_t *source, length_t l
 		lzo1x_1_compress(source, len, dest, &lzolen, lzo_wrkmem);
 		return lzolen;
 #else
-		return -1;
+		return 0;
 #endif
 	} else if(level < 10) {
 #ifdef HAVE_ZLIB
@@ -226,18 +226,18 @@ static length_t compress_packet(uint8_t *dest, const uint8_t *source, length_t l
 			return destlen;
 		} else
 #endif
-			return -1;
+			return 0;
 	} else {
 #ifdef HAVE_LZO
 		lzo_uint lzolen = MAXSIZE;
 		lzo1x_999_compress(source, len, dest, &lzolen, lzo_wrkmem);
 		return lzolen;
 #else
-		return -1;
+		return 0;
 #endif
 	}
 
-	return -1;
+	return 0;
 }
 
 static length_t uncompress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level) {
@@ -252,7 +252,7 @@ static length_t uncompress_packet(uint8_t *dest, const uint8_t *source, length_t
 			return lzolen;
 		} else
 #endif
-			return -1;
+			return 0;
 	}
 
 #ifdef HAVE_ZLIB
@@ -275,13 +275,13 @@ static length_t uncompress_packet(uint8_t *dest, const uint8_t *source, length_t
 		if(inflate(&stream, Z_FINISH) == Z_STREAM_END) {
 			return stream.total_out;
 		} else {
-			return -1;
+			return 0;
 		}
 	}
 
 #endif
 
-	return -1;
+	return 0;
 }
 
 /* VPN packet I/O */
@@ -305,7 +305,7 @@ static bool try_mac(node_t *n, const vpn_packet_t *inpkt) {
 	return false;
 #else
 
-	if(!n->status.validkey_in || !digest_active(n->indigest) || inpkt->len < sizeof(seqno_t) + digest_length(n->indigest)) {
+	if(!n->status.validkey_in || !digest_active(n->indigest) || (size_t)inpkt->len < sizeof(seqno_t) + digest_length(n->indigest)) {
 		return false;
 	}
 
@@ -364,7 +364,7 @@ static bool receive_udppacket(node_t *n, vpn_packet_t *inpkt) {
 
 	/* Check packet length */
 
-	if(inpkt->len < sizeof(seqno_t) + digest_length(n->indigest)) {
+	if((size_t)inpkt->len < sizeof(seqno_t) + digest_length(n->indigest)) {
 		logger(DEBUG_TRAFFIC, LOG_DEBUG, "Got too short packet from %s (%s)",
 		       n->name, n->hostname);
 		return false;
@@ -426,7 +426,7 @@ static bool receive_udppacket(node_t *n, vpn_packet_t *inpkt) {
 					return false;
 				}
 			} else {
-				for(int i = n->received_seqno + 1; i < seqno; i++) {
+				for(seqno_t i = n->received_seqno + 1; i < seqno; i++) {
 					n->late[(i / 8) % replaywin] |= 1 << i % 8;
 				}
 			}
@@ -453,7 +453,7 @@ static bool receive_udppacket(node_t *n, vpn_packet_t *inpkt) {
 	if(n->incompression) {
 		vpn_packet_t *outpkt = pkt[nextpkt++];
 
-		if((outpkt->len = uncompress_packet(DATA(outpkt), DATA(inpkt), inpkt->len, n->incompression)) < 0) {
+		if(!(outpkt->len = uncompress_packet(DATA(outpkt), DATA(inpkt), inpkt->len, n->incompression))) {
 			logger(DEBUG_TRAFFIC, LOG_ERR, "Error while uncompressing packet from %s (%s)",
 			       n->name, n->hostname);
 			return false;
@@ -484,7 +484,7 @@ static bool receive_udppacket(node_t *n, vpn_packet_t *inpkt) {
 #endif
 }
 
-void receive_tcppacket(connection_t *c, const char *buffer, int len) {
+void receive_tcppacket(connection_t *c, const char *buffer, size_t len) {
 	vpn_packet_t outpkt;
 	outpkt.offset = DEFAULT_PACKET_OFFSET;
 
@@ -505,7 +505,7 @@ void receive_tcppacket(connection_t *c, const char *buffer, int len) {
 	receive_packet(c->node, &outpkt);
 }
 
-bool receive_tcppacket_sptps(connection_t *c, const char *data, int len) {
+bool receive_tcppacket_sptps(connection_t *c, const char *data, size_t len) {
 	if(len < sizeof(node_id_t) + sizeof(node_id_t)) {
 		logger(DEBUG_PROTOCOL, LOG_ERR, "Got too short TCP SPTPS packet from %s (%s)", c->name, c->hostname);
 		return false;
@@ -596,9 +596,9 @@ static void send_sptps_packet(node_t *n, vpn_packet_t *origpkt) {
 
 	if(n->outcompression) {
 		outpkt.offset = 0;
-		int len = compress_packet(DATA(&outpkt) + offset, DATA(origpkt) + offset, origpkt->len - offset, n->outcompression);
+		length_t len = compress_packet(DATA(&outpkt) + offset, DATA(origpkt) + offset, origpkt->len - offset, n->outcompression);
 
-		if(len < 0) {
+		if(!len) {
 			logger(DEBUG_TRAFFIC, LOG_ERR, "Error while compressing packet to %s (%s)", n->name, n->hostname);
 		} else if(len < origpkt->len - offset) {
 			outpkt.len = len + offset;
@@ -753,7 +753,7 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) {
 	if(n->outcompression) {
 		outpkt = pkt[nextpkt++];
 
-		if((outpkt->len = compress_packet(DATA(outpkt), DATA(inpkt), inpkt->len, n->outcompression)) < 0) {
+		if(!(outpkt->len = compress_packet(DATA(outpkt), DATA(inpkt), inpkt->len, n->outcompression))) {
 			logger(DEBUG_TRAFFIC, LOG_ERR, "Error while compressing packet to %s (%s)",
 			       n->name, n->hostname);
 			return;
@@ -907,7 +907,7 @@ bool send_sptps_data(node_t *to, node_t *from, int type, const void *data, size_
 	if(relay_supported) {
 		if(direct) {
 			/* Inform the recipient that this packet was sent directly. */
-			node_id_t nullid = {{0}};
+			node_id_t nullid = {0};
 			memcpy(buf_ptr, &nullid, sizeof(nullid));
 			buf_ptr += sizeof(nullid);
 		} else {
@@ -1017,7 +1017,7 @@ bool receive_sptps_record(void *handle, uint8_t type, const void *data, uint16_t
 	if(type & PKT_COMPRESSED) {
 		length_t ulen = uncompress_packet(DATA(&inpkt) + offset, (const uint8_t *)data, len, from->incompression);
 
-		if(ulen < 0) {
+		if(!ulen) {
 			return false;
 		} else {
 			inpkt.len = ulen + offset;
@@ -1609,7 +1609,7 @@ static node_t *try_harder(const sockaddr_t *from, const vpn_packet_t *pkt) {
 
 static void handle_incoming_vpn_packet(listen_socket_t *ls, vpn_packet_t *pkt, sockaddr_t *addr) {
 	char *hostname;
-	node_id_t nullid = {{0}};
+	node_id_t nullid = {0};
 	node_t *from, *to;
 	bool direct = false;
 
@@ -1726,6 +1726,8 @@ skip_harder:
 }
 
 void handle_incoming_vpn_data(void *data, int flags) {
+	(void)data;
+	(void)flags;
 	listen_socket_t *ls = data;
 
 #ifdef HAVE_RECVMMSG
@@ -1795,6 +1797,8 @@ void handle_incoming_vpn_data(void *data, int flags) {
 }
 
 void handle_device_data(void *data, int flags) {
+	(void)data;
+	(void)flags;
 	vpn_packet_t packet;
 	packet.offset = DEFAULT_PACKET_OFFSET;
 	packet.priority = 0;
diff --git a/src/net_setup.c b/src/net_setup.c
index d48c2299..ed69808d 100644
--- a/src/net_setup.c
+++ b/src/net_setup.c
@@ -215,7 +215,7 @@ static bool read_ecdsa_private_key(void) {
 		logger(DEBUG_ALWAYS, LOG_ERR, "Error reading Ed25519 private key file `%s': %s", fname, strerror(errno));
 
 		if(errno == ENOENT) {
-			logger(DEBUG_ALWAYS, LOG_INFO, "Create an Ed25519 keypair with `tinc -n %s generate-ed25519-keys'.", netname ? : ".");
+			logger(DEBUG_ALWAYS, LOG_INFO, "Create an Ed25519 keypair with `tinc -n %s generate-ed25519-keys'.", netname ? netname : ".");
 		}
 
 		free(fname);
@@ -307,7 +307,7 @@ static bool read_rsa_private_key(void) {
 		       fname, strerror(errno));
 
 		if(errno == ENOENT) {
-			logger(DEBUG_ALWAYS, LOG_INFO, "Create an RSA keypair with `tinc -n %s generate-rsa-keys'.", netname ? : ".");
+			logger(DEBUG_ALWAYS, LOG_INFO, "Create an RSA keypair with `tinc -n %s generate-rsa-keys'.", netname ? netname : ".");
 		}
 
 		free(fname);
diff --git a/src/net_socket.c b/src/net_socket.c
index 75b20ec9..dcf8372c 100644
--- a/src/net_socket.c
+++ b/src/net_socket.c
@@ -624,6 +624,7 @@ begin:
 }
 
 void setup_outgoing_connection(outgoing_t *outgoing, bool verbose) {
+	(void)verbose;
 	timeout_del(&outgoing->ev);
 
 	node_t *n = outgoing->node;
@@ -655,6 +656,7 @@ remove:
   new connection
 */
 void handle_new_meta_connection(void *data, int flags) {
+	(void)flags;
 	listen_socket_t *l = data;
 	connection_t *c;
 	sockaddr_t sa;
@@ -747,6 +749,7 @@ void handle_new_meta_connection(void *data, int flags) {
   accept a new UNIX socket connection
 */
 void handle_new_unix_connection(void *data, int flags) {
+	(void)flags;
 	io_t *io = data;
 	connection_t *c;
 	sockaddr_t sa;
diff --git a/src/netutl.c b/src/netutl.c
index 4e58911c..2916e9ae 100644
--- a/src/netutl.c
+++ b/src/netutl.c
@@ -54,7 +54,7 @@ struct addrinfo *str2addrinfo(const char *address, const char *service, int sock
 
 sockaddr_t str2sockaddr(const char *address, const char *port) {
 	struct addrinfo *ai, hint = {0};
-	sockaddr_t result = {{0}};
+	sockaddr_t result = {0};
 	int err;
 
 	hint.ai_family = AF_UNSPEC;
diff --git a/src/node.c b/src/node.c
index 4ec5d353..b5e033c1 100644
--- a/src/node.c
+++ b/src/node.c
@@ -152,7 +152,7 @@ void node_del(node_t *n) {
 }
 
 node_t *lookup_node(char *name) {
-	node_t n = {NULL};
+	node_t n = {0};
 
 	n.name = name;
 
@@ -213,14 +213,14 @@ bool dump_nodes(connection_t *c) {
 
 		id[sizeof(id) - 1] = 0;
 		send_request(c, "%d %d %s %s %s %d %d %d %d %x %x %s %s %d %d %d %d %ld %d %"PRIu64" %"PRIu64" %"PRIu64" %"PRIu64, CONTROL, REQ_DUMP_NODES,
-		             n->name, id, n->hostname ? : "unknown port unknown",
+		             n->name, id, n->hostname ? n->hostname : "unknown port unknown",
 #ifdef DISABLE_LEGACY
 		             0, 0, 0,
 #else
 		             cipher_get_nid(n->outcipher), digest_get_nid(n->outdigest), (int)digest_length(n->outdigest),
 #endif
 		             n->outcompression, n->options, bitfield_to_int(&n->status, sizeof(n->status)),
-		             n->nexthop ? n->nexthop->name : "-", n->via ? n->via->name ? : "-" : "-", n->distance,
+		             n->nexthop ? n->nexthop->name : "-", n->via && n->via->name ? n->via->name : "-", n->distance,
 		             n->mtu, n->minmtu, n->maxmtu, (long)n->last_state_change, n->udp_ping_rtt,
 		             n->in_packets, n->in_bytes, n->out_packets, n->out_bytes);
 	}
diff --git a/src/openssl/crypto.c b/src/openssl/crypto.c
index 6894d876..e594e73a 100644
--- a/src/openssl/crypto.c
+++ b/src/openssl/crypto.c
@@ -46,7 +46,9 @@ static void random_exit(void) {
 	close(random_fd);
 }
 
-void randomize(void *out, size_t outlen) {
+void randomize(void *vout, size_t outlen) {
+	char *out = vout;
+
 	while(outlen) {
 		size_t len = read(random_fd, out, outlen);
 
diff --git a/src/openssl/prf.c b/src/openssl/prf.c
index d87c5c68..37af2ef5 100644
--- a/src/openssl/prf.c
+++ b/src/openssl/prf.c
@@ -29,7 +29,7 @@
    We use SHA512 instead of MD5 and SHA1.
  */
 
-static bool prf_xor(int nid, const char *secret, size_t secretlen, char *seed, size_t seedlen, char *out, ssize_t outlen) {
+static bool prf_xor(int nid, const char *secret, size_t secretlen, char *seed, size_t seedlen, char *out, size_t outlen) {
 	digest_t *digest = digest_open_by_nid(nid, -1);
 
 	if(!digest) {
@@ -67,7 +67,7 @@ static bool prf_xor(int nid, const char *secret, size_t secretlen, char *seed, s
 		}
 
 		/* XOR the results of the outer HMAC into the out buffer */
-		for(int i = 0; i < len && i < outlen; i++) {
+		for(size_t i = 0; i < len && i < outlen; i++) {
 			*out++ ^= hash[i];
 		}
 
diff --git a/src/openssl/rsa.c b/src/openssl/rsa.c
index e1ae4f61..0e811722 100644
--- a/src/openssl/rsa.c
+++ b/src/openssl/rsa.c
@@ -46,7 +46,7 @@ rsa_t *rsa_set_hex_public_key(char *n, char *e) {
 	BIGNUM *bn_n = NULL;
 	BIGNUM *bn_e = NULL;
 
-	if(BN_hex2bn(&bn_n, n) != strlen(n) || BN_hex2bn(&bn_e, e) != strlen(e)) {
+	if((size_t)BN_hex2bn(&bn_n, n) != strlen(n) || (size_t)BN_hex2bn(&bn_e, e) != strlen(e)) {
 		BN_free(bn_e);
 		BN_free(bn_n);
 		return false;
@@ -68,7 +68,7 @@ rsa_t *rsa_set_hex_private_key(char *n, char *e, char *d) {
 	BIGNUM *bn_e = NULL;
 	BIGNUM *bn_d = NULL;
 
-	if(BN_hex2bn(&bn_n, n) != strlen(n) || BN_hex2bn(&bn_e, e) != strlen(e) || BN_hex2bn(&bn_d, d) != strlen(d)) {
+	if((size_t)BN_hex2bn(&bn_n, n) != strlen(n) || (size_t)BN_hex2bn(&bn_e, e) != strlen(e) || (size_t)BN_hex2bn(&bn_d, d) != strlen(d)) {
 		BN_free(bn_d);
 		BN_free(bn_e);
 		BN_free(bn_n);
@@ -118,7 +118,7 @@ size_t rsa_size(rsa_t *rsa) {
 }
 
 bool rsa_public_encrypt(rsa_t *rsa, void *in, size_t len, void *out) {
-	if(RSA_public_encrypt(len, in, out, rsa, RSA_NO_PADDING) == len) {
+	if((size_t)RSA_public_encrypt(len, in, out, rsa, RSA_NO_PADDING) == len) {
 		return true;
 	}
 
@@ -127,7 +127,7 @@ bool rsa_public_encrypt(rsa_t *rsa, void *in, size_t len, void *out) {
 }
 
 bool rsa_private_decrypt(rsa_t *rsa, void *in, size_t len, void *out) {
-	if(RSA_private_decrypt(len, in, out, rsa, RSA_NO_PADDING) == len) {
+	if((size_t)RSA_private_decrypt(len, in, out, rsa, RSA_NO_PADDING) == len) {
 		return true;
 	}
 
diff --git a/src/openssl/rsagen.c b/src/openssl/rsagen.c
index c8546971..79127f68 100644
--- a/src/openssl/rsagen.c
+++ b/src/openssl/rsagen.c
@@ -32,6 +32,8 @@ typedef RSA rsa_t;
 /* This function prettyprints the key generation process */
 
 static int indicator(int a, int b, BN_GENCB *cb) {
+	(void)cb;
+
 	switch(a) {
 	case 0:
 		fprintf(stderr, ".");
diff --git a/src/protocol.c b/src/protocol.c
index c7dd8fb4..1ca24e57 100644
--- a/src/protocol.c
+++ b/src/protocol.c
@@ -76,7 +76,7 @@ bool send_request(connection_t *c, const char *format, ...) {
 	request[sizeof(request) - 1] = 0;
 	va_end(args);
 
-	if(len < 0 || len > sizeof(request) - 1) {
+	if(len < 0 || (size_t)len > sizeof(request) - 1) {
 		logger(DEBUG_ALWAYS, LOG_ERR, "Output buffer overflow while sending request to %s (%s)",
 		       c->name, c->hostname);
 		return false;
@@ -175,6 +175,7 @@ static void free_past_request(past_request_t *r) {
 static timeout_t past_request_timeout;
 
 static void age_past_requests(void *data) {
+	(void)data;
 	int left = 0, deleted = 0;
 
 	for splay_each(past_request_t, p, past_request_tree) {
@@ -196,7 +197,7 @@ static void age_past_requests(void *data) {
 }
 
 bool seen_request(const char *request) {
-	past_request_t *new, p = {NULL};
+	past_request_t *new, p = {0};
 
 	p.request = request;
 
diff --git a/src/protocol_auth.c b/src/protocol_auth.c
index 9d61ab8f..eb1754c1 100644
--- a/src/protocol_auth.c
+++ b/src/protocol_auth.c
@@ -176,6 +176,8 @@ bool send_id(connection_t *c) {
 }
 
 static bool finalize_invitation(connection_t *c, const char *data, uint16_t len) {
+	(void)len;
+
 	if(strchr(data, '\n')) {
 		logger(DEBUG_ALWAYS, LOG_ERR, "Received invalid key from invited node %s (%s)!\n", c->name, c->hostname);
 		return false;
@@ -606,7 +608,7 @@ bool metakey_h(connection_t *c, const char *request) {
 
 	/* Convert the challenge from hexadecimal back to binary */
 
-	int inlen = hex2bin(hexkey, enckey, sizeof(enckey));
+	size_t inlen = hex2bin(hexkey, enckey, sizeof(enckey));
 
 	/* Check if the length of the meta key is all right */
 
@@ -762,7 +764,7 @@ bool chal_reply_h(connection_t *c, const char *request) {
 
 	/* Convert the hash to binary format */
 
-	int inlen = hex2bin(hishash, hishash, sizeof(hishash));
+	size_t inlen = hex2bin(hishash, hishash, sizeof(hishash));
 
 	/* Check if the length of the hash is all right */
 
diff --git a/src/protocol_edge.c b/src/protocol_edge.c
index 9fd301f2..d650c36f 100644
--- a/src/protocol_edge.c
+++ b/src/protocol_edge.c
@@ -70,7 +70,7 @@ bool add_edge_h(connection_t *c, const char *request) {
 	char to_port[MAX_STRING_SIZE];
 	char address_local[MAX_STRING_SIZE];
 	char port_local[MAX_STRING_SIZE];
-	sockaddr_t address, local_address = {{0}};
+	sockaddr_t address, local_address = {0};
 	uint32_t options;
 	int weight;
 
diff --git a/src/protocol_key.c b/src/protocol_key.c
index a0a18462..58a3bd20 100644
--- a/src/protocol_key.c
+++ b/src/protocol_key.c
@@ -100,10 +100,13 @@ static bool send_sptps_data_myself(void *handle, uint8_t type, const void *data,
 }
 
 static bool send_initial_sptps_data(void *handle, uint8_t type, const void *data, size_t len) {
+	(void)type;
 	node_t *to = handle;
 	to->sptps.send_data = send_sptps_data_myself;
 	char buf[len * 4 / 3 + 5];
+
 	b64encode(data, buf, len);
+
 	return send_request(to->nexthop->connection, "%d %s %s %d %s", REQ_KEY, myself->name, to->name, REQ_KEY, buf);
 }
 
@@ -131,6 +134,8 @@ bool send_req_key(node_t *to) {
 /* REQ_KEY is overloaded to allow arbitrary requests to be routed between two nodes. */
 
 static bool req_key_ext_h(connection_t *c, const char *request, node_t *from, node_t *to, int reqno) {
+	(void)c;
+
 	/* If this is a SPTPS packet, see if sending UDP info helps.
 	   Note that we only do this if we're the destination or the static relay;
 	   otherwise every hop would initiate its own UDP info message, resulting in elevated chatter. */
@@ -227,7 +232,7 @@ static bool req_key_ext_h(connection_t *c, const char *request, node_t *from, no
 		}
 
 		char buf[MAX_STRING_SIZE];
-		int len;
+		size_t len;
 
 		if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, buf) != 1 || !(len = b64decode(buf, buf, strlen(buf)))) {
 			logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "REQ_SPTPS_START", from->name, from->hostname, "invalid SPTPS data");
@@ -466,7 +471,7 @@ bool ans_key_h(connection_t *c, const char *request) {
 
 	if(from->status.sptps) {
 		char buf[strlen(key)];
-		int len = b64decode(key, buf, strlen(key));
+		size_t len = b64decode(key, buf, strlen(key));
 
 		if(!len || !sptps_receive_data(&from->sptps, buf, len)) {
 			/* Uh-oh. It might be that the tunnel is stuck in some corrupted state,
@@ -519,14 +524,14 @@ bool ans_key_h(connection_t *c, const char *request) {
 		from->outdigest = NULL;
 	}
 
-	if(maclength != digest_length(from->outdigest)) {
+	if((size_t)maclength != digest_length(from->outdigest)) {
 		logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses bogus MAC length!", from->name, from->hostname);
 		return false;
 	}
 
 	/* Process key */
 
-	int keylen = hex2bin(key, key, sizeof(key));
+	size_t keylen = hex2bin(key, key, sizeof(key));
 
 	if(keylen != (from->outcipher ? cipher_keylength(from->outcipher) : 1)) {
 		logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses wrong keylength!", from->name, from->hostname);
diff --git a/src/protocol_misc.c b/src/protocol_misc.c
index d808d73f..a4fcd6f7 100644
--- a/src/protocol_misc.c
+++ b/src/protocol_misc.c
@@ -44,6 +44,8 @@ bool send_termreq(connection_t *c) {
 }
 
 bool termreq_h(connection_t *c, const char *request) {
+	(void)c;
+	(void)request;
 	return false;
 }
 
@@ -55,6 +57,7 @@ bool send_ping(connection_t *c) {
 }
 
 bool ping_h(connection_t *c, const char *request) {
+	(void)request;
 	return send_pong(c);
 }
 
@@ -63,6 +66,7 @@ bool send_pong(connection_t *c) {
 }
 
 bool pong_h(connection_t *c, const char *request) {
+	(void)request;
 	c->status.pinged = false;
 
 	/* Successful connection, reset timeout if this is an outgoing connection. */
diff --git a/src/protocol_subnet.c b/src/protocol_subnet.c
index 3e82e473..53afb8a4 100644
--- a/src/protocol_subnet.c
+++ b/src/protocol_subnet.c
@@ -46,7 +46,7 @@ bool add_subnet_h(connection_t *c, const char *request) {
 	char subnetstr[MAX_STRING_SIZE];
 	char name[MAX_STRING_SIZE];
 	node_t *owner;
-	subnet_t s = {NULL}, *new, *old;
+	subnet_t s = {0}, *new, *old;
 
 	if(sscanf(request, "%*d %*x " MAX_STRING " " MAX_STRING, name, subnetstr) != 2) {
 		logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "ADD_SUBNET", c->name,
@@ -162,7 +162,7 @@ bool del_subnet_h(connection_t *c, const char *request) {
 	char subnetstr[MAX_STRING_SIZE];
 	char name[MAX_STRING_SIZE];
 	node_t *owner;
-	subnet_t s = {NULL}, *find;
+	subnet_t s = {0}, *find;
 
 	if(sscanf(request, "%*d %*x " MAX_STRING " " MAX_STRING, name, subnetstr) != 2) {
 		logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "DEL_SUBNET", c->name,
diff --git a/src/route.c b/src/route.c
index 4d712795..3beb2f41 100644
--- a/src/route.c
+++ b/src/route.c
@@ -495,6 +495,7 @@ static void clamp_mss(const node_t *source, const node_t *via, vpn_packet_t *pac
 }
 
 static void age_subnets(void *data) {
+	(void)data;
 	bool left = false;
 
 	for splay_each(subnet_t, s, myself->subnet_tree) {
diff --git a/src/splay_tree.c b/src/splay_tree.c
index ee855192..4d973732 100644
--- a/src/splay_tree.c
+++ b/src/splay_tree.c
@@ -25,7 +25,7 @@
 /* Splay operation */
 
 static splay_node_t *splay_top_down(splay_tree_t *tree, const void *data, int *result) {
-	splay_node_t left = {NULL}, right = {NULL};
+	splay_node_t left = {0}, right = {0};
 	splay_node_t *leftbottom = &left, *rightbottom = &right, *child, *grandchild;
 	splay_node_t *root = tree->root;
 	int c;
diff --git a/src/sptps.c b/src/sptps.c
index 82e913eb..eeaf833e 100644
--- a/src/sptps.c
+++ b/src/sptps.c
@@ -51,9 +51,16 @@ unsigned int sptps_replaywin = 16;
 */
 
 void sptps_log_quiet(sptps_t *s, int s_errno, const char *format, va_list ap) {
+	(void)s;
+	(void)s_errno;
+	(void)format;
+	(void)ap;
 }
 
 void sptps_log_stderr(sptps_t *s, int s_errno, const char *format, va_list ap) {
+	(void)s;
+	(void)s_errno;
+
 	vfprintf(stderr, format, ap);
 	fputc('\n', stderr);
 }
@@ -62,6 +69,9 @@ void (*sptps_log)(sptps_t *s, int s_errno, const char *format, va_list ap) = spt
 
 // Log an error message.
 static bool error(sptps_t *s, int s_errno, const char *format, ...) {
+	(void)s;
+	(void)s_errno;
+
 	if(format) {
 		va_list ap;
 		va_start(ap, format);
@@ -244,6 +254,8 @@ static bool send_ack(sptps_t *s) {
 
 // Receive an ACKnowledgement record.
 static bool receive_ack(sptps_t *s, const char *data, uint16_t len) {
+	(void)data;
+
 	if(len) {
 		return error(s, EIO, "Invalid ACK record length");
 	}
@@ -381,6 +393,7 @@ static bool receive_handshake(sptps_t *s, const char *data, uint16_t len) {
 			return false;
 		}
 
+	// Fall through
 	case SPTPS_KEX:
 
 		// We have sent our KEX request, we expect our peer to sent one as well.
@@ -466,7 +479,7 @@ static bool sptps_check_seqno(sptps_t *s, uint32_t seqno, bool update_state) {
 				}
 			} else if(update_state) {
 				// We missed some packets. Mark them in the bitmap as being late.
-				for(int i = s->inseqno; i < seqno; i++) {
+				for(uint32_t i = s->inseqno; i < seqno; i++) {
 					s->late[(i / 8) % s->replaywin] |= 1 << i % 8;
 				}
 			}
@@ -495,11 +508,12 @@ static bool sptps_check_seqno(sptps_t *s, uint32_t seqno, bool update_state) {
 }
 
 // Check datagram for valid HMAC
-bool sptps_verify_datagram(sptps_t *s, const void *data, size_t len) {
+bool sptps_verify_datagram(sptps_t *s, const void *vdata, size_t len) {
 	if(!s->instate || len < 21) {
 		return error(s, EIO, "Received short packet");
 	}
 
+	const char *data = vdata;
 	uint32_t seqno;
 	memcpy(&seqno, data, 4);
 	seqno = ntohl(seqno);
@@ -584,7 +598,8 @@ static bool sptps_receive_data_datagram(sptps_t *s, const char *data, size_t len
 }
 
 // Receive incoming data. Check if it contains a complete record, if so, handle it.
-size_t sptps_receive_data(sptps_t *s, const void *data, size_t len) {
+size_t sptps_receive_data(sptps_t *s, const void *vdata, size_t len) {
+	const char *data = vdata;
 	size_t total_read = 0;
 
 	if(!s->state) {
diff --git a/src/sptps_keypair.c b/src/sptps_keypair.c
index 1bf2da01..51a94eeb 100644
--- a/src/sptps_keypair.c
+++ b/src/sptps_keypair.c
@@ -28,10 +28,14 @@
 static char *program_name;
 
 void logger(int level, int priority, const char *format, ...) {
+	(void)level;
+	(void)priority;
 	va_list ap;
+
 	va_start(ap, format);
 	vfprintf(stderr, format, ap);
 	va_end(ap);
+
 	fputc('\n', stderr);
 }
 
diff --git a/src/sptps_test.c b/src/sptps_test.c
index 0f75c242..4ff701ef 100644
--- a/src/sptps_test.c
+++ b/src/sptps_test.c
@@ -32,12 +32,20 @@
 
 // Symbols necessary to link with logger.o
 bool send_request(void *c, const char *msg, ...) {
+	(void)c;
+	(void)msg;
 	return false;
 }
+
 struct list_t *connection_list = NULL;
+
 bool send_meta(void *c, const char *msg, int len) {
+	(void)c;
+	(void)msg;
+	(void)len;
 	return false;
 }
+
 char *logfilename = NULL;
 bool do_detach = false;
 struct timeval now;
@@ -51,6 +59,7 @@ static int out = 1;
 static int addressfamily = AF_UNSPEC;
 
 static bool send_data(void *handle, uint8_t type, const void *data, size_t len) {
+	(void)type;
 	char hex[len * 2 + 1];
 	bin2hex(data, hex, len);
 
@@ -60,7 +69,7 @@ static bool send_data(void *handle, uint8_t type, const void *data, size_t len)
 
 	const int *sock = handle;
 
-	if(send(*sock, data, len, 0) != len) {
+	if((size_t)send(*sock, data, len, 0) != len) {
 		return false;
 	}
 
@@ -68,6 +77,7 @@ static bool send_data(void *handle, uint8_t type, const void *data, size_t len)
 }
 
 static bool receive_record(void *handle, uint8_t type, const void *data, uint16_t len) {
+	(void)handle;
 	if(verbose) {
 		fprintf(stderr, "Received type %d record of %u bytes:\n", type, len);
 	}
@@ -404,7 +414,7 @@ int main(int argc, char *argv[]) {
 				if(len > 1) {
 					sptps_send_record(&s, 0, buf, len);
 				}
-			} else if(!sptps_send_record(&s, buf[0] == '!' ? 1 : 0, buf, (len == 1 && buf[0] == '\n') ? 0 : buf[0] == '*' ? sizeof(buf) : len)) {
+			} else if(!sptps_send_record(&s, buf[0] == '!' ? 1 : 0, buf, (len == 1 && buf[0] == '\n') ? 0 : buf[0] == '*' ? sizeof(buf) : (size_t)len)) {
 				return 1;
 			}
 		}
diff --git a/src/subnet_parse.c b/src/subnet_parse.c
index 88513f68..d5b84eb6 100644
--- a/src/subnet_parse.c
+++ b/src/subnet_parse.c
@@ -371,7 +371,7 @@ bool str2net(subnet_t *subnet, const char *subnetstr) {
 
 bool net2str(char *netstr, int len, const subnet_t *subnet) {
 	if(!netstr || !subnet) {
-		logger(DEBUG_ALWAYS, LOG_ERR, "net2str() was called with netstr=%p, subnet=%p!", netstr, subnet);
+		logger(DEBUG_ALWAYS, LOG_ERR, "net2str() was called with netstr=%p, subnet=%p!", (void *)netstr, (void *)subnet);
 		return false;
 	}
 
diff --git a/src/tincctl.c b/src/tincctl.c
index 4f6660a9..93c5b320 100644
--- a/src/tincctl.c
+++ b/src/tincctl.c
@@ -388,7 +388,7 @@ ask_filename:
 		/* The directory is a relative path or a filename. */
 		getcwd(directory, sizeof(directory));
 
-		if(snprintf(buf2, sizeof(buf2), "%s" SLASH "%s", directory, filename) >= sizeof(buf2)) {
+		if((size_t)snprintf(buf2, sizeof(buf2), "%s" SLASH "%s", directory, filename) >= sizeof(buf2)) {
 			fprintf(stderr, "Filename too long: %s" SLASH "%s\n", directory, filename);
 
 			if(ask && tty) {
@@ -577,7 +577,7 @@ bool recvline(int fd, char *line, size_t len) {
 		blen += result;
 	}
 
-	if(newline - buffer >= len) {
+	if((size_t)(newline - buffer) >= len) {
 		return false;
 	}
 
@@ -591,11 +591,7 @@ bool recvline(int fd, char *line, size_t len) {
 	return true;
 }
 
-bool recvdata(int fd, char *data, size_t len) {
-	if(len == -1) {
-		len = blen;
-	}
-
+static bool recvdata(int fd, char *data, size_t len) {
 	while(blen < len) {
 		int result = recv(fd, buffer + blen, sizeof(buffer) - blen, 0);
 
@@ -618,7 +614,7 @@ bool recvdata(int fd, char *data, size_t len) {
 bool sendline(int fd, char *format, ...) {
 	static char buffer[4096];
 	char *p = buffer;
-	int blen = 0;
+	int blen;
 	va_list ap;
 
 	va_start(ap, format);
@@ -626,7 +622,7 @@ bool sendline(int fd, char *format, ...) {
 	buffer[sizeof(buffer) - 1] = 0;
 	va_end(ap);
 
-	if(blen < 1 || blen >= sizeof(buffer)) {
+	if(blen < 1 || (size_t)blen >= sizeof(buffer)) {
 		return false;
 	}
 
@@ -649,7 +645,7 @@ bool sendline(int fd, char *format, ...) {
 	return true;
 }
 
-static void pcap(int fd, FILE *out, int snaplen) {
+static void pcap(int fd, FILE *out, uint32_t snaplen) {
 	sendline(fd, "%d %d %d", CONTROL, REQ_PCAP, snaplen);
 	char data[9018];
 
@@ -665,7 +661,7 @@ static void pcap(int fd, FILE *out, int snaplen) {
 		0xa1b2c3d4,
 		2, 4,
 		0, 0,
-		snaplen ? : sizeof(data),
+		snaplen ? snaplen : sizeof(data),
 		1,
 	};
 
@@ -688,7 +684,7 @@ static void pcap(int fd, FILE *out, int snaplen) {
 		int n = sscanf(line, "%d %d %d", &code, &req, &len);
 		gettimeofday(&tv, NULL);
 
-		if(n != 3 || code != CONTROL || req != REQ_PCAP || len < 0 || len > sizeof(data)) {
+		if(n != 3 || code != CONTROL || req != REQ_PCAP || len < 0 || (size_t)len > sizeof(data)) {
 			break;
 		}
 
@@ -715,7 +711,7 @@ static void logcontrol(int fd, FILE *out, int level) {
 		int code, req, len;
 		int n = sscanf(line, "%d %d %d", &code, &req, &len);
 
-		if(n != 3 || code != CONTROL || req != REQ_LOG || len < 0 || len > sizeof(data)) {
+		if(n != 3 || code != CONTROL || req != REQ_LOG || len < 0 || (size_t)len > sizeof(data)) {
 			break;
 		}
 
@@ -1080,6 +1076,8 @@ static int cmd_start(int argc, char *argv[]) {
 }
 
 static int cmd_stop(int argc, char *argv[]) {
+	(void)argv;
+
 	if(argc > 1) {
 		fprintf(stderr, "Too many arguments!\n");
 		return 1;
@@ -1128,6 +1126,8 @@ static int cmd_restart(int argc, char *argv[]) {
 }
 
 static int cmd_reload(int argc, char *argv[]) {
+	(void)argv;
+
 	if(argc > 1) {
 		fprintf(stderr, "Too many arguments!\n");
 		return 1;
@@ -1176,7 +1176,7 @@ static int dump_invitations(void) {
 
 		char fname[PATH_MAX];
 
-		if(snprintf(fname, sizeof(fname), "%s" SLASH "%s", dname, ent->d_name) >= sizeof(fname)) {
+		if((size_t)snprintf(fname, sizeof(fname), "%s" SLASH "%s", dname, ent->d_name) >= sizeof(fname)) {
 			fprintf(stderr, "Filename too long: %s" SLASH "%s\n", dname, ent->d_name);
 			continue;
 		}
@@ -1421,6 +1421,8 @@ static int cmd_dump(int argc, char *argv[]) {
 }
 
 static int cmd_purge(int argc, char *argv[]) {
+	(void)argv;
+
 	if(argc > 1) {
 		fprintf(stderr, "Too many arguments!\n");
 		return 1;
@@ -1465,6 +1467,8 @@ static int cmd_debug(int argc, char *argv[]) {
 }
 
 static int cmd_retry(int argc, char *argv[]) {
+	(void)argv;
+
 	if(argc > 1) {
 		fprintf(stderr, "Too many arguments!\n");
 		return 1;
@@ -1535,6 +1539,8 @@ static int cmd_disconnect(int argc, char *argv[]) {
 }
 
 static int cmd_top(int argc, char *argv[]) {
+	(void)argv;
+
 	if(argc > 1) {
 		fprintf(stderr, "Too many arguments!\n");
 		return 1;
@@ -1570,6 +1576,8 @@ static int cmd_pcap(int argc, char *argv[]) {
 
 #ifdef SIGINT
 static void sigint_handler(int sig) {
+	(void)sig;
+
 	fprintf(stderr, "\n");
 	shutdown(fd, SHUT_RDWR);
 }
@@ -1601,6 +1609,8 @@ static int cmd_log(int argc, char *argv[]) {
 }
 
 static int cmd_pid(int argc, char *argv[]) {
+	(void)argv;
+
 	if(argc > 1) {
 		fprintf(stderr, "Too many arguments!\n");
 		return 1;
@@ -1949,7 +1959,7 @@ static int cmd_config(int argc, char *argv[]) {
 	FILE *tf = NULL;
 
 	if(action >= -1) {
-		if(snprintf(tmpfile, sizeof(tmpfile), "%s.config.tmp", filename) >= sizeof(tmpfile)) {
+		if((size_t)snprintf(tmpfile, sizeof(tmpfile), "%s.config.tmp", filename) >= sizeof(tmpfile)) {
 			fprintf(stderr, "Filename too long: %s.config.tmp\n", filename);
 			return 1;
 		}
@@ -2336,6 +2346,8 @@ static int cmd_generate_rsa_keys(int argc, char *argv[]) {
 #endif
 
 static int cmd_generate_ed25519_keys(int argc, char *argv[]) {
+	(void)argv;
+
 	if(argc > 1) {
 		fprintf(stderr, "Too many arguments!\n");
 		return 1;
@@ -2349,11 +2361,16 @@ static int cmd_generate_ed25519_keys(int argc, char *argv[]) {
 }
 
 static int cmd_help(int argc, char *argv[]) {
+	(void)argc;
+	(void)argv;
+
 	usage(false);
 	return 0;
 }
 
 static int cmd_version(int argc, char *argv[]) {
+	(void)argv;
+
 	if(argc > 1) {
 		fprintf(stderr, "Too many arguments!\n");
 		return 1;
@@ -2422,7 +2439,13 @@ static int cmd_edit(int argc, char *argv[]) {
 
 	char *command;
 #ifndef HAVE_MINGW
-	xasprintf(&command, "\"%s\" \"%s\"", getenv("VISUAL") ? : getenv("EDITOR") ? : "vi", filename);
+	const char *editor = getenv("VISUAL");
+	if (!editor)
+		editor = getenv("EDITOR");
+	if (!editor)
+		editor = "vi";
+
+	xasprintf(&command, "\"%s\" \"%s\"", editor, filename);
 #else
 	xasprintf(&command, "edit \"%s\"", filename);
 #endif
@@ -2471,6 +2494,8 @@ static int export(const char *name, FILE *out) {
 }
 
 static int cmd_export(int argc, char *argv[]) {
+	(void)argv;
+
 	if(argc > 1) {
 		fprintf(stderr, "Too many arguments!\n");
 		return 1;
@@ -2493,6 +2518,8 @@ static int cmd_export(int argc, char *argv[]) {
 }
 
 static int cmd_export_all(int argc, char *argv[]) {
+	(void)argv;
+
 	if(argc > 1) {
 		fprintf(stderr, "Too many arguments!\n");
 		return 1;
@@ -2533,6 +2560,8 @@ static int cmd_export_all(int argc, char *argv[]) {
 }
 
 static int cmd_import(int argc, char *argv[]) {
+	(void)argv;
+
 	if(argc > 1) {
 		fprintf(stderr, "Too many arguments!\n");
 		return 1;
@@ -2560,7 +2589,7 @@ static int cmd_import(int argc, char *argv[]) {
 				fclose(out);
 			}
 
-			if(snprintf(filename, sizeof(filename), "%s" SLASH "%s", hosts_dir, name) >= sizeof(filename)) {
+			if((size_t)snprintf(filename, sizeof(filename), "%s" SLASH "%s", hosts_dir, name) >= sizeof(filename)) {
 				fprintf(stderr, "Filename too long: %s" SLASH "%s\n", hosts_dir, name);
 				return 1;
 			}
@@ -2612,11 +2641,11 @@ static int cmd_import(int argc, char *argv[]) {
 }
 
 static int cmd_exchange(int argc, char *argv[]) {
-	return cmd_export(argc, argv) ? : cmd_import(argc, argv);
+	return cmd_export(argc, argv) ? 1 : cmd_import(argc, argv);
 }
 
 static int cmd_exchange_all(int argc, char *argv[]) {
-	return cmd_export_all(argc, argv) ? : cmd_import(argc, argv);
+	return cmd_export_all(argc, argv) ? 1 : cmd_import(argc, argv);
 }
 
 static int switch_network(char *name) {
@@ -2694,6 +2723,8 @@ static int cmd_network(int argc, char *argv[]) {
 }
 
 static int cmd_fsck(int argc, char *argv[]) {
+	(void)argv;
+
 	if(argc > 1) {
 		fprintf(stderr, "Too many arguments!\n");
 		return 1;
@@ -2962,48 +2993,48 @@ static const struct {
 	int (*function)(int argc, char *argv[]);
 	bool hidden;
 } commands[] = {
-	{"start", cmd_start},
-	{"stop", cmd_stop},
-	{"restart", cmd_restart},
-	{"reload", cmd_reload},
-	{"dump", cmd_dump},
-	{"list", cmd_dump},
-	{"purge", cmd_purge},
-	{"debug", cmd_debug},
-	{"retry", cmd_retry},
-	{"connect", cmd_connect},
-	{"disconnect", cmd_disconnect},
-	{"top", cmd_top},
-	{"pcap", cmd_pcap},
-	{"log", cmd_log},
-	{"pid", cmd_pid},
+	{"start", cmd_start, false},
+	{"stop", cmd_stop, false},
+	{"restart", cmd_restart, false},
+	{"reload", cmd_reload, false},
+	{"dump", cmd_dump, false},
+	{"list", cmd_dump, false},
+	{"purge", cmd_purge, false},
+	{"debug", cmd_debug, false},
+	{"retry", cmd_retry, false},
+	{"connect", cmd_connect, false},
+	{"disconnect", cmd_disconnect, false},
+	{"top", cmd_top, false},
+	{"pcap", cmd_pcap, false},
+	{"log", cmd_log, false},
+	{"pid", cmd_pid, false},
 	{"config", cmd_config, true},
-	{"add", cmd_config},
-	{"del", cmd_config},
-	{"get", cmd_config},
-	{"set", cmd_config},
-	{"init", cmd_init},
-	{"generate-keys", cmd_generate_keys},
+	{"add", cmd_config, false},
+	{"del", cmd_config, false},
+	{"get", cmd_config, false},
+	{"set", cmd_config, false},
+	{"init", cmd_init, false},
+	{"generate-keys", cmd_generate_keys, false},
 #ifndef DISABLE_LEGACY
-	{"generate-rsa-keys", cmd_generate_rsa_keys},
+	{"generate-rsa-keys", cmd_generate_rsa_keys, false},
 #endif
-	{"generate-ed25519-keys", cmd_generate_ed25519_keys},
-	{"help", cmd_help},
-	{"version", cmd_version},
-	{"info", cmd_info},
-	{"edit", cmd_edit},
-	{"export", cmd_export},
-	{"export-all", cmd_export_all},
-	{"import", cmd_import},
-	{"exchange", cmd_exchange},
-	{"exchange-all", cmd_exchange_all},
-	{"invite", cmd_invite},
-	{"join", cmd_join},
-	{"network", cmd_network},
-	{"fsck", cmd_fsck},
-	{"sign", cmd_sign},
-	{"verify", cmd_verify},
-	{NULL, NULL},
+	{"generate-ed25519-keys", cmd_generate_ed25519_keys, false},
+	{"help", cmd_help, false},
+	{"version", cmd_version, false},
+	{"info", cmd_info, false},
+	{"edit", cmd_edit, false},
+	{"export", cmd_export, false},
+	{"export-all", cmd_export_all, false},
+	{"import", cmd_import, false},
+	{"exchange", cmd_exchange, false},
+	{"exchange-all", cmd_exchange_all, false},
+	{"invite", cmd_invite, false},
+	{"join", cmd_join, false},
+	{"network", cmd_network, false},
+	{"fsck", cmd_fsck, false},
+	{"sign", cmd_sign, false},
+	{"verify", cmd_verify, false},
+	{NULL, NULL, false},
 };
 
 #ifdef HAVE_READLINE
@@ -3121,10 +3152,13 @@ static char *complete_info(const char *text, int state) {
 }
 
 static char *complete_nothing(const char *text, int state) {
+	(void)text;
+	(void)state;
 	return NULL;
 }
 
 static char **completion(const char *text, int start, int end) {
+	(void)end;
 	char **matches = NULL;
 
 	if(!start) {
diff --git a/src/top.c b/src/top.c
index 792f2240..ab146195 100644
--- a/src/top.c
+++ b/src/top.c
@@ -239,7 +239,7 @@ static int sortfunc(const void *a, const void *b) {
 static void redraw(void) {
 	erase();
 
-	mvprintw(0, 0, "Tinc %-16s  Nodes: %4d  Sort: %-10s  %s", netname ? : "", node_list.count, sortname[sortmode], cumulative ? "Cumulative" : "Current");
+	mvprintw(0, 0, "Tinc %-16s  Nodes: %4d  Sort: %-10s  %s", netname ? netname : "", node_list.count, sortname[sortmode], cumulative ? "Cumulative" : "Current");
 	attrset(A_REVERSE);
 	mvprintw(2, 0, "Node                IN %s   IN %s   OUT %s  OUT %s", punit, bunit, punit, bunit);
 	chgat(-1, A_REVERSE, 0, NULL);
diff --git a/src/upnp.c b/src/upnp.c
index 5149714d..5e41d1b6 100644
--- a/src/upnp.c
+++ b/src/upnp.c
@@ -148,6 +148,8 @@ static void upnp_refresh() {
 }
 
 static void *upnp_thread(void *data) {
+	(void)data;
+
 	while(true) {
 		time_t start = time(NULL);
 		upnp_refresh();
diff --git a/src/utils.c b/src/utils.c
index 364ae430..857d47ed 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -53,9 +53,9 @@ static int charhex2bin(char c) {
 	}
 }
 
-int hex2bin(const char *src, void *vdst, int length) {
+size_t hex2bin(const char *src, void *vdst, size_t length) {
 	char *dst = vdst;
-	int i;
+	size_t i;
 
 	for(i = 0; i < length && isxdigit(src[i * 2]) && isxdigit(src[i * 2 + 1]); i++) {
 		dst[i] = charhex2bin(src[i * 2]) * 16 + charhex2bin(src[i * 2 + 1]);
@@ -64,10 +64,10 @@ int hex2bin(const char *src, void *vdst, int length) {
 	return i;
 }
 
-int bin2hex(const void *vsrc, char *dst, int length) {
+size_t bin2hex(const void *vsrc, char *dst, size_t length) {
 	const char *src = vsrc;
 
-	for(int i = length - 1; i >= 0; i--) {
+	for(size_t i = length; i-- > 0;) {
 		dst[i * 2 + 1] = hexadecimals[(unsigned char) src[i] & 15];
 		dst[i * 2] = hexadecimals[(unsigned char) src[i] >> 4];
 	}
@@ -76,8 +76,8 @@ int bin2hex(const void *vsrc, char *dst, int length) {
 	return length * 2;
 }
 
-int b64decode(const char *src, void *dst, int length) {
-	int i;
+size_t b64decode(const char *src, void *dst, size_t length) {
+	size_t i;
 	uint32_t triplet = 0;
 	unsigned char *udst = (unsigned char *)dst;
 
@@ -116,11 +116,11 @@ int b64decode(const char *src, void *dst, int length) {
 	}
 }
 
-static int b64encode_internal(const void *src, char *dst, int length, const char *alphabet) {
+static size_t b64encode_internal(const void *src, char *dst, size_t length, const char *alphabet) {
 	uint32_t triplet;
 	const unsigned char *usrc = (unsigned char *)src;
-	int si = length / 3 * 3;
-	int di = length / 3 * 4;
+	size_t si = length / 3 * 3;
+	size_t di = length / 3 * 4;
 
 	switch(length % 3) {
 	case 2:
@@ -165,11 +165,11 @@ static int b64encode_internal(const void *src, char *dst, int length, const char
 	return length;
 }
 
-int b64encode(const void *src, char *dst, int length) {
+size_t b64encode(const void *src, char *dst, size_t length) {
 	return b64encode_internal(src, dst, length, base64_original);
 }
 
-int b64encode_urlsafe(const void *src, char *dst, int length) {
+size_t b64encode_urlsafe(const void *src, char *dst, size_t length) {
 	return b64encode_internal(src, dst, length, base64_urlsafe);
 }
 
diff --git a/src/utils.h b/src/utils.h
index a0f64bb0..42851501 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -21,12 +21,12 @@
     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
 
-extern int hex2bin(const char *src, void *dst, int length);
-extern int bin2hex(const void *src, char *dst, int length);
+extern size_t hex2bin(const char *src, void *dst, size_t length);
+extern size_t bin2hex(const void *src, char *dst, size_t length);
 
-extern int b64encode(const void *src, char *dst, int length);
-extern int b64encode_urlsafe(const void *src, char *dst, int length);
-extern int b64decode(const char *src, void *dst, int length);
+extern size_t b64encode(const void *src, char *dst, size_t length);
+extern size_t b64encode_urlsafe(const void *src, char *dst, size_t length);
+extern size_t b64decode(const char *src, void *dst, size_t length);
 
 #ifdef HAVE_MINGW
 extern const char *winerror(int);
-- 
2.20.1