sdhcp

commit d64b498944cd8ca265e167f130992dff5b744e68
parent 2a32d2ca9330dbf0c660827daf2da3d3e657697d
Author: Hiltjo Posthuma <hiltjo@codemadness.org>
Date:   Mon, 27 Apr 2015 22:59:41 +0200

code-style, remove debug.c, config.mk: default c99

Diffstat:
M
TODO
 | 
5
+----
M
config.mk
 | 
5
++---
D
debug.c
 | 
148
-------------------------------------------------------------------------------
M
sdhcp.c
 | 
90
++++++++++++++++++++++++++++++++++---------------------------------------------
M
util/eprintf.c
 | 
14
++++++--------

5 files changed, 48 insertions(+), 214 deletions(-)
diff --git a/TODO b/TODO
@@ -2,9 +2,6 @@ TODO:
 [ ] manual check memcpy bounds.
 [ ] add flag (-s?) to probe a specific DHCP server, not broadcast?
     probably skip in run() Init: etc stages.
-[ ] sane default value for client-id and test it.
-[ ] add new options to man page (-d, -i).
-[ ] update LICENSE.
 [ ] replace unsigned char ip[4] and so on from function declarations.
 [?] ipv6 support ?
 
@@ -20,7 +17,6 @@ Changed (for now):
 	- typos:
 		- sdhcp.c: interface typo.
 		- sdhcp.1: shdcp typo.
-	- make exit([01]), EXIT_SUCCESS or EXIT_FAILURE.
 	- replace write() for stdout messages with fprintf()
 	- replace die() with eprintf().
 	- makefile:
@@ -33,6 +29,7 @@ Changed (for now):
 		  "vaio".
 		- add -d flag, don't update /etc/resolv.conf.
 		- add -i flag, don't set ip.
+		- add -f flag, run in foreground.
 		- add -e flag, run program, this has the following variables set:
 		  $SERVER, DHCP ip.
 		  $DNS, DNS ip.
diff --git a/config.mk b/config.mk
@@ -6,8 +6,7 @@ DESTDIR   =
 MANPREFIX = $(PREFIX)/share/man
 
 CC        = cc
-#CC       = musl-gcc
 LD        = $(CC)
 CPPFLAGS  = -D_BSD_SOURCE
-CFLAGS    = -g -Wall -Wextra -O0 -ansi $(CPPFLAGS)
-LDFLAGS   = -g
+CFLAGS    = -Wall -Wextra -pedantic -std=c99 $(CPPFLAGS)
+LDFLAGS   =
diff --git a/debug.c b/debug.c
@@ -1,148 +0,0 @@
-#include <stdarg.h>
-
-void bpdump(unsigned char *p, int n);
-
-unsigned short
-nhgets(unsigned char c[2])
-{
-	return ((c[0] << 8) + c[1]) & 0xffff;
-}
-
-unsigned long
-nhgetl(unsigned char c[4])
-{
-	return (nhgets(c) << 16) + nhgets(c + 2);
-}
-
-char *
-ipstr(unsigned char *ip)
-{
-	char * ch = malloc(3 * 4 + 3 + 10);
-	sprintf(ch, "%d.%d.%d.%d", ip[0], ip[1], ip[2], ip[3]);
-	return ch;
-}
-
-#if 0
-void
-dbgprintf(char *str, ...)
-{
-	va_list ap;
-	va_start(ap, str);
-	vfprintf(stderr, str, ap);
-	va_end(ap);
-}
-#endif
-
-void
-bpdump(unsigned char *p, int n)
-{
-	int len, i, code;
-	Bootp *bp;
-	unsigned char type;
-	char *types[] = {
-		"discover", "offer", "request",
-		"decline", "ack", "nak", "release", "inform"
-	};
-	/* Udphdr *up; */
-
-	bp = (Bootp*)p;
-	/* up = (Udphdr*)bp->udphdr; */
-
-	if(n < bp->magic - p) {
-		fprintf(stderr, "dhcpclient: short bootp packet");
-		return;
-	}
-
-	optget(bp, &type, ODtype, sizeof type);
-	fprintf(stderr, "DHCP%s\n", types[type - 1]);
-	/* fprintf(stderr, "laddr=%I lport=%d raddr=%I rport=%d\n", up->laddr,
-	nhgets(up->lport), up->raddr, nhgets(up->rport)); */
-	fprintf(stderr, "op = %d htype = %d hlen = %d hops = %d\n", *bp->op, *bp->htype,
-	        *bp->hlen, *bp->hops);
-	fprintf(stderr, "xid = %x secs = %d flags = %x\n", nhgetl(bp->xid),
-	        nhgets(bp->secs), nhgets(bp->flags));
-	fprintf(stderr, "ciaddr = %s, yiaddr = %s, siaddr = %s, giaddr = %s\n",
-	        ipstr(bp->ciaddr), ipstr(bp->yiaddr), ipstr(bp->siaddr), ipstr(bp->giaddr));
-	fprintf(stderr, "chaddr =");
-	for(i=0; i<15; i++)
-		fprintf(stderr, "%.2x:", bp->chaddr[i]);
-	fprintf(stderr, "%.2x\n", bp->chaddr[15]);
-	fprintf(stderr, "sname = %s\n", bp->sname);
-	fprintf(stderr, "file = %s\n", bp->file);
-
-	n -= bp->magic - p;
-	p = bp->magic;
-
-	if(n < 4)
-		return;
-	if(memcmp(magic, p, 4) != 0)
-		fprintf(stderr, "dhcpclient: bad opt magic %#x %#x %#x %#x\n",
-		        p[0], p[1], p[2], p[3]);
-	p += 4;
-	n -= 4;
-
-	while(n > 0) {
-		code = *p++;
-		n--;
-		if(code == OBpad)
-			continue;
-		if(code == OBend)
-			break;
-		if(n == 0) {
-			fprintf(stderr, " bad option: %d", code);
-			return;
-		}
-		len = *p++;
-		n--;
-		if(len > n) {
-			fprintf(stderr, " bad option: %d", code);
-			return;
-		}
-		switch(code) {
-		case ODtype:
-			fprintf(stderr, "DHCP type %d\n", p[0]);
-			break;
-		case ODclientid:
-			fprintf(stderr, "client id=");
-			for(i = 0; i<len; i++)
-				fprintf(stderr, "%x ", p[i]);
-			fprintf(stderr, "\n");
-			break;
-		case ODlease:
-			fprintf(stderr, "lease=%d sec\n", nhgetl(p));
-			break;
-		case ODserverid:
-			fprintf(stderr, "server id=%s\n", ipstr(p));
-			break;
-		case OBmask:
-			fprintf(stderr, "mask=%s\n", ipstr(p));
-			break;
-		case OBrouter:
-			fprintf(stderr, "router=%s\n", ipstr(p));
-			break;
-		case ODipaddr:
-			fprintf(stderr, "ip addr=%s\n", ipstr(p));
-			break;
-		case OBdnsserver:
-			fprintf(stderr, "dns=%s\n", ipstr(p));
-			break;
-		case OBbaddr:
-			fprintf(stderr, "broadcast=%s\n", ipstr(p));
-			break;
-		case ODrenewaltime:
-			fprintf(stderr, "renew time=%d sec\n", nhgetl(p));
-			break;
-		case ODrebindingtime:
-			fprintf(stderr, "rebind time=%d sec\n", nhgetl(p));
-			break;
-		default:
-			fprintf(stderr, "unknown option %d\n", code);
-			for(i = 0; i<len; i++)
-				fprintf(stderr, "%x ", p[i]);
-			fprintf(stderr, "\n");
-			break;
-		}
-		p += len;
-		n -= len;
-	}
-}
diff --git a/sdhcp.c b/sdhcp.c
@@ -108,7 +108,7 @@ hnput(unsigned char *dst, unsigned long long src, size_t n)
 {
 	unsigned int i;
 
-	for(i = 0; n--; i++)
+	for (i = 0; n--; i++)
 		dst[i] = (src >> (n * 8)) & 0xff;
 }
 
@@ -120,6 +120,7 @@ iptoaddr(struct sockaddr *ifaddr, unsigned char ip[4], int port)
 	in->sin_family = AF_INET;
 	in->sin_port = htons(port);
 	memcpy(&(in->sin_addr), ip, sizeof in->sin_addr);
+
 	return ifaddr;
 }
 
@@ -132,8 +133,9 @@ udpsend(unsigned char ip[4], int fd, void *data, size_t n)
 	ssize_t sent;
 
 	iptoaddr(&addr, ip, 67); /* bootp server */
-	if((sent = sendto(fd, data, n, 0, &addr, addrlen)) == -1)
+	if ((sent = sendto(fd, data, n, 0, &addr, addrlen)) == -1)
 		eprintf("sendto:");
+
 	return sent;
 }
 
@@ -146,8 +148,9 @@ udprecv(unsigned char ip[4], int fd, void *data, size_t n)
 	ssize_t r;
 
 	iptoaddr(&addr, ip, 68); /* bootp client */
-	if((r = recvfrom(fd, data, n, 0, &addr, &addrlen)) == -1)
+	if ((r = recvfrom(fd, data, n, 0, &addr, &addrlen)) == -1)
 		eprintf("recvfrom:");
+
 	return r;
 }
 
@@ -163,7 +166,7 @@ setip(unsigned char ip[4], unsigned char mask[4], unsigned char gateway[4])
 
 	strlcpy(ifreq.ifr_name, ifname, IF_NAMESIZE);
 	iptoaddr(&(ifreq.ifr_addr), ip, 0);
-	if((fd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP)) == -1)
+	if ((fd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP)) == -1)
 		eprintf("can't set ip, socket:");
 	ioctl(fd, SIOCSIFADDR, &ifreq);
 	iptoaddr(&(ifreq.ifr_netmask), mask, 0);
@@ -186,9 +189,9 @@ cat(int dfd, char *src)
 	char buf[BUFSIZ];
 	int n, fd;
 
-	if((fd = open(src, O_RDONLY)) == -1)
+	if ((fd = open(src, O_RDONLY)) == -1)
 		return; /* can't read, but don't error out */
-	while((n = read(fd, buf, sizeof buf)) > 0)
+	while ((n = read(fd, buf, sizeof buf)) > 0)
 		write(dfd, buf, n);
 	close(fd);
 }
@@ -199,12 +202,12 @@ setdns(unsigned char dns[4])
 	char buf[128];
 	int fd;
 
-	if((fd = creat("/etc/resolv.conf", 0644)) == -1) {
+	if ((fd = creat("/etc/resolv.conf", 0644)) == -1) {
 		weprintf("can't change /etc/resolv.conf:");
 		return;
 	}
 	cat(fd, "/etc/resolv.conf.head");
-	if(snprintf(buf, sizeof(buf) - 1, "\nnameserver %d.%d.%d.%d\n",
+	if (snprintf(buf, sizeof(buf) - 1, "\nnameserver %d.%d.%d.%d\n",
 	         dns[0], dns[1], dns[2], dns[3]) > 0)
 		write(fd, buf, strlen(buf));
 	cat(fd, "/etc/resolv.conf.tail");
@@ -218,18 +221,18 @@ optget(Bootp *bp, void *data, int opt, int n)
 	unsigned char *top = ((unsigned char *)bp) + sizeof *bp;
 	int code, len;
 
-	while(p < top) {
+	while (p < top) {
 		code = *p++;
-		if(code == OBpad)
+		if (code == OBpad)
 			continue;
-		if(code == OBend || p == top)
+		if (code == OBend || p == top)
 			break;
 		len = *p++;
-		if(len > top - p)
+		if (len > top - p)
 			break;
-		if(code == opt) {
+		if (code == opt) {
 			memcpy(data, p, MIN(len, n));
-			return;
+			break;
 		}
 		p += len;
 	}
@@ -241,6 +244,7 @@ optput(unsigned char *p, int opt, unsigned char *data, size_t len)
 	*p++ = opt;
 	*p++ = (unsigned char)len;
 	memcpy(p, data, len);
+
 	return p + len;
 }
 
@@ -250,6 +254,7 @@ hnoptput(unsigned char *p, int opt, long long data, size_t len)
 	*p++ = opt;
 	*p++ = (unsigned char)len;
 	hnput(p, data, len);
+
 	return p + len;
 }
 
@@ -303,14 +308,15 @@ dhcprecv(void)
 	pfd.events = POLLIN;
 
 	memset(&bp, 0, sizeof bp);
-	if(poll(&pfd, 1, -1) == -1) {
-		if(errno != EINTR)
+	if (poll(&pfd, 1, -1) == -1) {
+		if (errno != EINTR)
 			eprintf("poll:");
 		else
 			return Timeout;
 	}
 	udprecv(IP(255, 255, 255, 255), sock, &bp, sizeof bp);
 	optget(&bp, &type, ODtype, sizeof type);
+
 	return type;
 }
 
@@ -319,11 +325,11 @@ acceptlease(void)
 {
 	char buf[128];
 
-	if(iflag == 1)
+	if (iflag)
 		setip(client, mask, router);
-	if(dflag == 1)
+	if (dflag)
 		setdns(dns);
-	if(*program) {
+	if (*program) {
 		snprintf(buf, sizeof(buf), "%d.%d.%d.%d", server[0], server[1], server[2], server[3]);
 		setenv("SERVER", buf, 1);
 		snprintf(buf, sizeof(buf), "%d.%d.%d.%d", client[0], client[1], client[2], client[3]);
@@ -344,20 +350,6 @@ run(void)
 {
 	int forked = 0;
 
-#if 0
-InitReboot:
-	/* send DHCPrequest to old server */
-	dhcpsend(DHCPrequest, Broadcast);
-	goto Rebooting;
-Rebooting:
-	switch (dhcprecv()) {
-	case DHCPnak:
-		goto Init;
-	case DHCPack:
-		acceptoffer();
-		goto Bound;
-	}
-#endif
 Init:
 	dhcpsend(DHCPdiscover, Broadcast);
 	alarm(1);
@@ -384,20 +376,15 @@ Requesting:
 	switch(dhcprecv()) {
 	case DHCPoffer:
 		goto Requesting; /* ignore other offers. */
-#if 0
-	case DHCPack: /* (and you don't want it) ? */
-		dhcpsend(DHCPdecline, Unicast);
-		goto Init;
-#endif
 	case DHCPack:
 		acceptlease();
 		goto Bound;
 	}
 Bound:
 	fputs("Congrats! You should be on the 'net.\n", stdout);
-	if(!fflag && !forked) {
-		if(fork())
-			exit(EXIT_SUCCESS);
+	if (!fflag && !forked) {
+		if (fork())
+			exit(0);
 		forked = 1;
 	}
 	switch (dhcprecv()) {
@@ -441,13 +428,13 @@ void cleanexit(int unused)
 {
 	(void) unused;
 	dhcpsend(DHCPrelease, Unicast);
-	exit(EXIT_SUCCESS);
+	exit(0);
 }
 
 static void
 usage(void)
 {
-	eprintf("usage: sdhcp [-d] [-e program] [-f] [-i] [ifname] [clientid]\n");
+	eprintf("usage: %s [-d] [-e program] [-f] [-i] [ifname] [clientid]\n", argv0);
 }
 
 int
@@ -476,36 +463,37 @@ main(int argc, char *argv[])
 		break;
 	} ARGEND;
 
-	if(argc >= 1)
+	if (argc)
 		ifname = argv[0]; /* interface name */
-	if(argc >= 2)
+	if (argc >= 2)
 		cid = argv[1]; /* client-id */
 
 	memset(&ifreq, 0, sizeof(ifreq));
 	signal(SIGALRM, nop);
 	signal(SIGTERM, cleanexit);
 
-	if((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
+	if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
 		eprintf("socket:");
-	if(setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &bcast, sizeof bcast) == -1)
+	if (setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &bcast, sizeof bcast) == -1)
 		eprintf("setsockopt:");
 
 	strlcpy(ifreq.ifr_name, ifname, IF_NAMESIZE);
 	ioctl(sock, SIOCGIFINDEX, &ifreq);
-	if(setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, &ifreq, sizeof ifreq) == -1)
+	if (setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, &ifreq, sizeof ifreq) == -1)
 		eprintf("setsockopt:");
 	iptoaddr(&addr, IP(255, 255, 255, 255), 68);
-	if(bind(sock, (void*)&addr, sizeof addr) != 0)
+	if (bind(sock, (void*)&addr, sizeof addr) != 0)
 		eprintf("bind:");
 	ioctl(sock, SIOCGIFHWADDR, &ifreq);
 	memcpy(hwaddr, ifreq.ifr_hwaddr.sa_data, sizeof ifreq.ifr_hwaddr.sa_data);
 
-	if((rnd = open("/dev/urandom", O_RDONLY)) == -1)
+	if ((rnd = open("/dev/urandom", O_RDONLY)) == -1)
 		eprintf("can't open /dev/urandom to generate unique transaction identifier:");
 	read(rnd, xid, sizeof xid);
 	close(rnd);
 
 	starttime = time(NULL);
 	run();
-	return EXIT_SUCCESS;
+
+	return 0;
 }
diff --git a/util/eprintf.c b/util/eprintf.c
@@ -16,7 +16,7 @@ eprintf(const char *fmt, ...)
 	va_list ap;
 
 	va_start(ap, fmt);
-	venprintf(EXIT_FAILURE, fmt, ap);
+	venprintf(1, fmt, ap);
 	va_end(ap);
 }
 
@@ -33,13 +33,12 @@ enprintf(int status, const char *fmt, ...)
 void
 venprintf(int status, const char *fmt, va_list ap)
 {
-#ifdef DEBUG
-	fprintf(stderr, "%s: ", argv0);
-#endif
+	if (strncmp(fmt, "usage", strlen("usage")))
+		fprintf(stderr, "%s: ", argv0);
 
 	vfprintf(stderr, fmt, ap);
 
-	if(fmt[0] && fmt[strlen(fmt)-1] == ':') {
+	if (fmt[0] && fmt[strlen(fmt)-1] == ':') {
 		fputc(' ', stderr);
 		perror(NULL);
 	}
@@ -52,9 +51,8 @@ weprintf(const char *fmt, ...)
 {
 	va_list ap;
 
-#ifdef DEBUG
-	fprintf(stderr, "%s: ", argv0);
-#endif
+	if (strncmp(fmt, "usage", strlen("usage")))
+		fprintf(stderr, "%s: ", argv0);
 
 	va_start(ap, fmt);
 	vfprintf(stderr, fmt, ap);