From 4940fc889e1e63667a15243028ddcd84d471cd8e Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Sat, 7 May 2011 23:00:07 +0000 Subject: [PATCH] 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 Signed-off-by: David S. Miller --- drivers/net/netconsole.c | 20 +++------------ include/linux/if_ether.h | 1 + net/core/netpoll.c | 26 +------------------- net/core/pktgen.c | 53 ++++++---------------------------------- net/core/utils.c | 24 ++++++++++++++++++ 5 files changed, 38 insertions(+), 86 deletions(-) diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c index 62fdbaa1fb60..a83e101440fd 100644 --- a/drivers/net/netconsole.c +++ b/drivers/net/netconsole.c @@ -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; } /* diff --git a/include/linux/if_ether.h b/include/linux/if_ether.h index be69043d2896..0f1325d98295 100644 --- a/include/linux/if_ether.h +++ b/include/linux/if_ether.h @@ -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 diff --git a/net/core/netpoll.c b/net/core/netpoll.c index 46d9c3a4de2f..2d7d6d473781 100644 --- a/net/core/netpoll.c +++ b/net/core/netpoll.c @@ -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); diff --git a/net/core/pktgen.c b/net/core/pktgen.c index d41d88b53e18..379270f14771 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c @@ -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; } diff --git a/net/core/utils.c b/net/core/utils.c index 5fea0ab21902..2012bc797f9c 100644 --- a/net/core/utils.c +++ b/net/core/utils.c @@ -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); -- GitLab