diff options
Diffstat (limited to 'networking/libiproute/ll_map.c')
| -rw-r--r-- | networking/libiproute/ll_map.c | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/networking/libiproute/ll_map.c b/networking/libiproute/ll_map.c new file mode 100644 index 0000000..eeae4e2 --- /dev/null +++ b/networking/libiproute/ll_map.c @@ -0,0 +1,200 @@ +/* vi: set sw=4 ts=4: */ +/* + * ll_map.c + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> + * + */ + +#include <net/if.h> /* struct ifreq and co. */ + +#include "libbb.h" +#include "libnetlink.h" +#include "ll_map.h" + +struct idxmap { + struct idxmap *next; + int index; + int type; + int alen; + unsigned flags; + unsigned char addr[8]; + char name[16]; +}; + +static struct idxmap *idxmap[16]; + +static struct idxmap *find_by_index(int idx) +{ + struct idxmap *im; + + for (im = idxmap[idx & 0xF]; im; im = im->next) + if (im->index == idx) + return im; + return NULL; +} + +int ll_remember_index(const struct sockaddr_nl *who UNUSED_PARAM, + struct nlmsghdr *n, + void *arg UNUSED_PARAM) +{ + int h; + struct ifinfomsg *ifi = NLMSG_DATA(n); + struct idxmap *im, **imp; + struct rtattr *tb[IFLA_MAX+1]; + + if (n->nlmsg_type != RTM_NEWLINK) + return 0; + + if (n->nlmsg_len < NLMSG_LENGTH(sizeof(ifi))) + return -1; + + memset(tb, 0, sizeof(tb)); + parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), IFLA_PAYLOAD(n)); + if (tb[IFLA_IFNAME] == NULL) + return 0; + + h = ifi->ifi_index & 0xF; + + for (imp = &idxmap[h]; (im = *imp) != NULL; imp = &im->next) + if (im->index == ifi->ifi_index) + goto found; + + im = xmalloc(sizeof(*im)); + im->next = *imp; + im->index = ifi->ifi_index; + *imp = im; + found: + im->type = ifi->ifi_type; + im->flags = ifi->ifi_flags; + if (tb[IFLA_ADDRESS]) { + int alen; + im->alen = alen = RTA_PAYLOAD(tb[IFLA_ADDRESS]); + if (alen > (int)sizeof(im->addr)) + alen = sizeof(im->addr); + memcpy(im->addr, RTA_DATA(tb[IFLA_ADDRESS]), alen); + } else { + im->alen = 0; + memset(im->addr, 0, sizeof(im->addr)); + } + strcpy(im->name, RTA_DATA(tb[IFLA_IFNAME])); + return 0; +} + +const char *ll_idx_n2a(int idx, char *buf) +{ + struct idxmap *im; + + if (idx == 0) + return "*"; + im = find_by_index(idx); + if (im) + return im->name; + snprintf(buf, 16, "if%d", idx); + return buf; +} + + +const char *ll_index_to_name(int idx) +{ + static char nbuf[16]; + + return ll_idx_n2a(idx, nbuf); +} + +#ifdef UNUSED +int ll_index_to_type(int idx) +{ + struct idxmap *im; + + if (idx == 0) + return -1; + im = find_by_index(idx); + if (im) + return im->type; + return -1; +} +#endif + +unsigned ll_index_to_flags(int idx) +{ + struct idxmap *im; + + if (idx == 0) + return 0; + im = find_by_index(idx); + if (im) + return im->flags; + return 0; +} + +int xll_name_to_index(const char *const name) +{ + int ret = 0; + int sock_fd; + +/* caching is not warranted - no users which repeatedly call it */ +#ifdef UNUSED + static char ncache[16]; + static int icache; + + struct idxmap *im; + int i; + + if (name == NULL) + goto out; + if (icache && strcmp(name, ncache) == 0) { + ret = icache; + goto out; + } + for (i = 0; i < 16; i++) { + for (im = idxmap[i]; im; im = im->next) { + if (strcmp(im->name, name) == 0) { + icache = im->index; + strcpy(ncache, name); + ret = im->index; + goto out; + } + } + } + /* We have not found the interface in our cache, but the kernel + * may still know about it. One reason is that we may be using + * module on-demand loading, which means that the kernel will + * load the module and make the interface exist only when + * we explicitely request it (check for dev_load() in net/core/dev.c). + * I can think of other similar scenario, but they are less common... + * Jean II */ +#endif + + sock_fd = socket(AF_INET, SOCK_DGRAM, 0); + if (sock_fd) { + struct ifreq ifr; + int tmp; + + strncpy(ifr.ifr_name, name, IFNAMSIZ); + ifr.ifr_ifindex = -1; + tmp = ioctl(sock_fd, SIOCGIFINDEX, &ifr); + close(sock_fd); + if (tmp >= 0) + /* In theory, we should redump the interface list + * to update our cache, this is left as an exercise + * to the reader... Jean II */ + ret = ifr.ifr_ifindex; + } +/* out:*/ + if (ret <= 0) + bb_error_msg_and_die("cannot find device \"%s\"", name); + return ret; +} + +int ll_init_map(struct rtnl_handle *rth) +{ + xrtnl_wilddump_request(rth, AF_UNSPEC, RTM_GETLINK); + xrtnl_dump_filter(rth, ll_remember_index, &idxmap); + return 0; +} |