code-style, remove debug.c, config.mk: default c99 - sdhcp - simple dhcp client
(HTM) git clone git://git.codemadness.org/sdhcp
(DIR) Log
(DIR) Files
(DIR) Refs
(DIR) LICENSE
---
(DIR) commit d64b498944cd8ca265e167f130992dff5b744e68
(DIR) parent 2a32d2ca9330dbf0c660827daf2da3d3e657697d
(HTM) 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(-)
---
(DIR) 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.
(DIR) 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 =
(DIR) 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;
- }
-}
(DIR) 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;
}
(DIR) 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);