diff options
Diffstat (limited to 'tc/m_skbmod.c')
| -rw-r--r-- | tc/m_skbmod.c | 234 |
1 files changed, 234 insertions, 0 deletions
diff --git a/tc/m_skbmod.c b/tc/m_skbmod.c new file mode 100644 index 0000000..b1c8d00 --- /dev/null +++ b/tc/m_skbmod.c @@ -0,0 +1,234 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * m_skbmod.c skb modifier action module + * + * Authors: J Hadi Salim (jhs@mojatatu.com) + */ + +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <fcntl.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <arpa/inet.h> +#include <string.h> +#include <linux/netdevice.h> + +#include "rt_names.h" +#include "utils.h" +#include "tc_util.h" +#include <linux/tc_act/tc_skbmod.h> + +static void skbmod_explain(void) +{ + fprintf(stderr, + "Usage:... skbmod { set <SETTABLE> | swap <SWAPPABLE> | ecn } [CONTROL] [index INDEX]\n" + "where SETTABLE is: [dmac DMAC] [smac SMAC] [etype ETYPE]\n" + "where SWAPPABLE is: \"mac\" to swap mac addresses\n" + "\tDMAC := 6 byte Destination MAC address\n" + "\tSMAC := optional 6 byte Source MAC address\n" + "\tETYPE := optional 16 bit ethertype\n" + "\tCONTROL := reclassify | pipe | drop | continue | ok |\n" + "\t goto chain <CHAIN_INDEX>\n" + "\tINDEX := skbmod index value to use\n"); +} + +static void skbmod_usage(void) +{ + skbmod_explain(); + exit(-1); +} + +static int parse_skbmod(struct action_util *a, int *argc_p, char ***argv_p, + int tca_id, struct nlmsghdr *n) +{ + int argc = *argc_p; + char **argv = *argv_p; + int ok = 0; + struct tc_skbmod p; + struct rtattr *tail; + char dbuf[ETH_ALEN]; + char sbuf[ETH_ALEN]; + __u16 skbmod_etype = 0; + char *daddr = NULL; + char *saddr = NULL; + + memset(&p, 0, sizeof(p)); + + if (argc <= 0) + return -1; + + while (argc > 0) { + if (matches(*argv, "skbmod") == 0) { + NEXT_ARG(); + continue; + } else if (matches(*argv, "swap") == 0) { + NEXT_ARG(); + continue; + } else if (matches(*argv, "mac") == 0) { + p.flags |= SKBMOD_F_SWAPMAC; + ok += 1; + } else if (matches(*argv, "set") == 0) { + NEXT_ARG(); + continue; + } else if (matches(*argv, "etype") == 0) { + NEXT_ARG(); + if (get_u16(&skbmod_etype, *argv, 0)) + invarg("ethertype is invalid", *argv); + fprintf(stderr, "skbmod etype 0x%x\n", skbmod_etype); + p.flags |= SKBMOD_F_ETYPE; + ok += 1; + } else if (matches(*argv, "dmac") == 0) { + NEXT_ARG(); + daddr = *argv; + if (sscanf(daddr, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", + dbuf, dbuf + 1, dbuf + 2, + dbuf + 3, dbuf + 4, dbuf + 5) != 6) { + fprintf(stderr, "Invalid dst mac address %s\n", + daddr); + return -1; + } + p.flags |= SKBMOD_F_DMAC; + fprintf(stderr, "dst MAC address <%s>\n", daddr); + ok += 1; + + } else if (matches(*argv, "smac") == 0) { + NEXT_ARG(); + saddr = *argv; + if (sscanf(saddr, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", + sbuf, sbuf + 1, sbuf + 2, + sbuf + 3, sbuf + 4, sbuf + 5) != 6) { + fprintf(stderr, "Invalid smac address %s\n", + saddr); + return -1; + } + p.flags |= SKBMOD_F_SMAC; + fprintf(stderr, "src MAC address <%s>\n", saddr); + ok += 1; + } else if (matches(*argv, "ecn") == 0) { + p.flags |= SKBMOD_F_ECN; + ok += 1; + } else if (matches(*argv, "help") == 0) { + skbmod_usage(); + } else { + break; + } + + argc--; + argv++; + } + + parse_action_control_dflt(&argc, &argv, &p.action, false, TC_ACT_PIPE); + + if (argc) { + if (matches(*argv, "index") == 0) { + NEXT_ARG(); + if (get_u32(&p.index, *argv, 0)) { + fprintf(stderr, "skbmod: Illegal \"index\"\n"); + return -1; + } + ok++; + argc--; + argv++; + } + } + + if (!ok) { + fprintf(stderr, "skbmod requires at least one option\n"); + skbmod_usage(); + } + + tail = addattr_nest(n, MAX_MSG, tca_id); + addattr_l(n, MAX_MSG, TCA_SKBMOD_PARMS, &p, sizeof(p)); + + if (daddr) + addattr_l(n, MAX_MSG, TCA_SKBMOD_DMAC, dbuf, ETH_ALEN); + if (skbmod_etype) + addattr16(n, MAX_MSG, TCA_SKBMOD_ETYPE, skbmod_etype); + if (saddr) + addattr_l(n, MAX_MSG, TCA_SKBMOD_SMAC, sbuf, ETH_ALEN); + + addattr_nest_end(n, tail); + + *argc_p = argc; + *argv_p = argv; + return 0; +} + +static int print_skbmod(struct action_util *au, FILE *f, struct rtattr *arg) +{ + struct tc_skbmod *p; + struct rtattr *tb[TCA_SKBMOD_MAX + 1]; + __u16 skbmod_etype = 0; + int has_optional = 0; + SPRINT_BUF(b1); + SPRINT_BUF(b2); + + if (arg == NULL) + return 0; + + parse_rtattr_nested(tb, TCA_SKBMOD_MAX, arg); + + if (tb[TCA_SKBMOD_PARMS] == NULL) { + fprintf(stderr, "Missing skbmod parameters\n"); + return -1; + } + + p = RTA_DATA(tb[TCA_SKBMOD_PARMS]); + + fprintf(f, "skbmod "); + print_action_control(f, "", p->action, " "); + + if (tb[TCA_SKBMOD_ETYPE]) { + skbmod_etype = rta_getattr_u16(tb[TCA_SKBMOD_ETYPE]); + has_optional = 1; + fprintf(f, "set etype 0x%X ", skbmod_etype); + } + + if (has_optional) + fprintf(f, "\n\t "); + + if (tb[TCA_SKBMOD_DMAC]) { + has_optional = 1; + fprintf(f, "set dmac %s ", + ll_addr_n2a(RTA_DATA(tb[TCA_SKBMOD_DMAC]), + RTA_PAYLOAD(tb[TCA_SKBMOD_DMAC]), 0, b1, + sizeof(b1))); + + } + + if (tb[TCA_SKBMOD_SMAC]) { + has_optional = 1; + fprintf(f, "set smac %s ", + ll_addr_n2a(RTA_DATA(tb[TCA_SKBMOD_SMAC]), + RTA_PAYLOAD(tb[TCA_SKBMOD_SMAC]), 0, b2, + sizeof(b2))); + } + + if (p->flags & SKBMOD_F_SWAPMAC) + fprintf(f, "swap mac "); + + if (p->flags & SKBMOD_F_ECN) + fprintf(f, "ecn "); + + fprintf(f, "\n\t index %u ref %d bind %d", p->index, p->refcnt, + p->bindcnt); + if (show_stats) { + if (tb[TCA_SKBMOD_TM]) { + struct tcf_t *tm = RTA_DATA(tb[TCA_SKBMOD_TM]); + + print_tm(f, tm); + } + } + + fprintf(f, "\n"); + + return 0; +} + +struct action_util skbmod_action_util = { + .id = "skbmod", + .parse_aopt = parse_skbmod, + .print_aopt = print_skbmod, +}; |