net: add mac_pton() for parsing MAC address

mac_pton() parses MAC address in form XX:XX:XX:XX:XX:XX and only in that form.

mac_pton() doesn't dirty result until it's sure string representation is valid.

mac_pton() doesn't care about characters _after_ last octet,
it's up to caller to deal with it.

mac_pton() diverges from 0/-E return value convention.
Target usage:

	if (!mac_pton(str, whatever->mac))
		return -EINVAL;
	/* ->mac being u8 [ETH_ALEN] is filled at this point. */
	/* optionally check str[3 * ETH_ALEN - 1] for termination */

Use mac_pton() in pktgen and netconsole for start.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Alexey Dobriyan 2011-05-07 23:00:07 +00:00 committed by David S. Miller
parent 99f823f98f
commit 4940fc889e
5 changed files with 38 additions and 86 deletions

View File

@ -429,8 +429,6 @@ static ssize_t store_remote_mac(struct netconsole_target *nt,
size_t count)
{
u8 remote_mac[ETH_ALEN];
char *p = (char *) buf;
int i;
if (nt->enabled) {
printk(KERN_ERR "netconsole: target (%s) is enabled, "
@ -439,23 +437,13 @@ static ssize_t store_remote_mac(struct netconsole_target *nt,
return -EINVAL;
}
for (i = 0; i < ETH_ALEN - 1; i++) {
remote_mac[i] = simple_strtoul(p, &p, 16);
if (*p != ':')
goto invalid;
p++;
}
remote_mac[ETH_ALEN - 1] = simple_strtoul(p, &p, 16);
if (*p && (*p != '\n'))
goto invalid;
if (!mac_pton(buf, remote_mac))
return -EINVAL;
if (buf[3 * ETH_ALEN - 1] && buf[3 * ETH_ALEN - 1] != '\n')
return -EINVAL;
memcpy(nt->np.remote_mac, remote_mac, ETH_ALEN);
return strnlen(buf, count);
invalid:
printk(KERN_ERR "netconsole: invalid input\n");
return -EINVAL;
}
/*

View File

@ -136,6 +136,7 @@ int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr);
extern struct ctl_table ether_table[];
#endif
int mac_pton(const char *s, u8 *mac);
extern ssize_t sysfs_format_mac(char *buf, const unsigned char *addr, int len);
#endif

View File

@ -698,32 +698,8 @@ int netpoll_parse_options(struct netpoll *np, char *opt)
if (*cur != 0) {
/* MAC address */
if ((delim = strchr(cur, ':')) == NULL)
if (!mac_pton(cur, np->remote_mac))
goto parse_failed;
*delim = 0;
np->remote_mac[0] = simple_strtol(cur, NULL, 16);
cur = delim + 1;
if ((delim = strchr(cur, ':')) == NULL)
goto parse_failed;
*delim = 0;
np->remote_mac[1] = simple_strtol(cur, NULL, 16);
cur = delim + 1;
if ((delim = strchr(cur, ':')) == NULL)
goto parse_failed;
*delim = 0;
np->remote_mac[2] = simple_strtol(cur, NULL, 16);
cur = delim + 1;
if ((delim = strchr(cur, ':')) == NULL)
goto parse_failed;
*delim = 0;
np->remote_mac[3] = simple_strtol(cur, NULL, 16);
cur = delim + 1;
if ((delim = strchr(cur, ':')) == NULL)
goto parse_failed;
*delim = 0;
np->remote_mac[4] = simple_strtol(cur, NULL, 16);
cur = delim + 1;
np->remote_mac[5] = simple_strtol(cur, NULL, 16);
}
netpoll_print_options(np);

View File

@ -1420,11 +1420,6 @@ static ssize_t pktgen_if_write(struct file *file,
return count;
}
if (!strcmp(name, "dst_mac")) {
char *v = valstr;
unsigned char old_dmac[ETH_ALEN];
unsigned char *m = pkt_dev->dst_mac;
memcpy(old_dmac, pkt_dev->dst_mac, ETH_ALEN);
len = strn_len(&user_buffer[i], sizeof(valstr) - 1);
if (len < 0)
return len;
@ -1432,35 +1427,16 @@ static ssize_t pktgen_if_write(struct file *file,
memset(valstr, 0, sizeof(valstr));
if (copy_from_user(valstr, &user_buffer[i], len))
return -EFAULT;
i += len;
for (*m = 0; *v && m < pkt_dev->dst_mac + 6; v++) {
int value;
value = hex_to_bin(*v);
if (value >= 0)
*m = *m * 16 + value;
if (*v == ':') {
m++;
*m = 0;
}
}
if (!mac_pton(valstr, pkt_dev->dst_mac))
return -EINVAL;
/* Set up Dest MAC */
if (compare_ether_addr(old_dmac, pkt_dev->dst_mac))
memcpy(&(pkt_dev->hh[0]), pkt_dev->dst_mac, ETH_ALEN);
memcpy(&pkt_dev->hh[0], pkt_dev->dst_mac, ETH_ALEN);
sprintf(pg_result, "OK: dstmac");
sprintf(pg_result, "OK: dstmac %pM", pkt_dev->dst_mac);
return count;
}
if (!strcmp(name, "src_mac")) {
char *v = valstr;
unsigned char old_smac[ETH_ALEN];
unsigned char *m = pkt_dev->src_mac;
memcpy(old_smac, pkt_dev->src_mac, ETH_ALEN);
len = strn_len(&user_buffer[i], sizeof(valstr) - 1);
if (len < 0)
return len;
@ -1468,26 +1444,13 @@ static ssize_t pktgen_if_write(struct file *file,
memset(valstr, 0, sizeof(valstr));
if (copy_from_user(valstr, &user_buffer[i], len))
return -EFAULT;
i += len;
for (*m = 0; *v && m < pkt_dev->src_mac + 6; v++) {
int value;
value = hex_to_bin(*v);
if (value >= 0)
*m = *m * 16 + value;
if (*v == ':') {
m++;
*m = 0;
}
}
if (!mac_pton(valstr, pkt_dev->src_mac))
return -EINVAL;
/* Set up Src MAC */
if (compare_ether_addr(old_smac, pkt_dev->src_mac))
memcpy(&(pkt_dev->hh[6]), pkt_dev->src_mac, ETH_ALEN);
memcpy(&pkt_dev->hh[6], pkt_dev->src_mac, ETH_ALEN);
sprintf(pg_result, "OK: srcmac");
sprintf(pg_result, "OK: srcmac %pM", pkt_dev->src_mac);
return count;
}

View File

@ -296,3 +296,27 @@ void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb,
csum_unfold(*sum)));
}
EXPORT_SYMBOL(inet_proto_csum_replace4);
int mac_pton(const char *s, u8 *mac)
{
int i;
/* XX:XX:XX:XX:XX:XX */
if (strlen(s) < 3 * ETH_ALEN - 1)
return 0;
/* Don't dirty result unless string is valid MAC. */
for (i = 0; i < ETH_ALEN; i++) {
if (!strchr("0123456789abcdefABCDEF", s[i * 3]))
return 0;
if (!strchr("0123456789abcdefABCDEF", s[i * 3 + 1]))
return 0;
if (i != ETH_ALEN - 1 && s[i * 3 + 2] != ':')
return 0;
}
for (i = 0; i < ETH_ALEN; i++) {
mac[i] = (hex_to_bin(s[i * 3]) << 4) | hex_to_bin(s[i * 3 + 1]);
}
return 1;
}
EXPORT_SYMBOL(mac_pton);