cregit-Linux how code gets into the kernel

Release 4.7 net/ipv6/netfilter/ip6t_rt.c

/* Kernel module to match ROUTING parameters. */

/* (C) 2001-2002 Andras Kis-Szabo <kisza@sch.bme.hu>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/ipv6.h>
#include <linux/types.h>
#include <net/checksum.h>
#include <net/ipv6.h>

#include <asm/byteorder.h>

#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
#include <linux/netfilter_ipv6/ip6t_rt.h>

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Xtables: IPv6 Routing Header match");
MODULE_AUTHOR("Andras Kis-Szabo <kisza@sch.bme.hu>");

/* Returns 1 if the id is matched by the range, 0 otherwise */

static inline bool segsleft_match(u_int32_t min, u_int32_t max, u_int32_t id, bool invert) { bool r; pr_debug("segsleft_match:%c 0x%x <= 0x%x <= 0x%x\n", invert ? '!' : ' ', min, id, max); r = (id >= min && id <= max) ^ invert; pr_debug(" result %s\n", r ? "PASS" : "FAILED"); return r; }

Contributors

PersonTokensPropCommitsCommitProp
harald welteharald welte6191.04%125.00%
jan engelhardtjan engelhardt45.97%250.00%
patrick mchardypatrick mchardy22.99%125.00%
Total67100.00%4100.00%


static bool rt_mt6(const struct sk_buff *skb, struct xt_action_param *par) { struct ipv6_rt_hdr _route; const struct ipv6_rt_hdr *rh; const struct ip6t_rt *rtinfo = par->matchinfo; unsigned int temp; unsigned int ptr = 0; unsigned int hdrlen = 0; bool ret = false; struct in6_addr _addr; const struct in6_addr *ap; int err; err = ipv6_find_hdr(skb, &ptr, NEXTHDR_ROUTING, NULL, NULL); if (err < 0) { if (err != -ENOENT) par->hotdrop = true; return false; } rh = skb_header_pointer(skb, ptr, sizeof(_route), &_route); if (rh == NULL) { par->hotdrop = true; return false; } hdrlen = ipv6_optlen(rh); if (skb->len - ptr < hdrlen) { /* Pcket smaller than its length field */ return false; } pr_debug("IPv6 RT LEN %u %u ", hdrlen, rh->hdrlen); pr_debug("TYPE %04X ", rh->type); pr_debug("SGS_LEFT %u %02X\n", rh->segments_left, rh->segments_left); pr_debug("IPv6 RT segsleft %02X ", segsleft_match(rtinfo->segsleft[0], rtinfo->segsleft[1], rh->segments_left, !!(rtinfo->invflags & IP6T_RT_INV_SGS))); pr_debug("type %02X %02X %02X ", rtinfo->rt_type, rh->type, (!(rtinfo->flags & IP6T_RT_TYP) || ((rtinfo->rt_type == rh->type) ^ !!(rtinfo->invflags & IP6T_RT_INV_TYP)))); pr_debug("len %02X %04X %02X ", rtinfo->hdrlen, hdrlen, !(rtinfo->flags & IP6T_RT_LEN) || ((rtinfo->hdrlen == hdrlen) ^ !!(rtinfo->invflags & IP6T_RT_INV_LEN))); pr_debug("res %02X %02X %02X ", rtinfo->flags & IP6T_RT_RES, ((const struct rt0_hdr *)rh)->reserved, !((rtinfo->flags & IP6T_RT_RES) && (((const struct rt0_hdr *)rh)->reserved))); ret = (rh != NULL) && (segsleft_match(rtinfo->segsleft[0], rtinfo->segsleft[1], rh->segments_left, !!(rtinfo->invflags & IP6T_RT_INV_SGS))) && (!(rtinfo->flags & IP6T_RT_LEN) || ((rtinfo->hdrlen == hdrlen) ^ !!(rtinfo->invflags & IP6T_RT_INV_LEN))) && (!(rtinfo->flags & IP6T_RT_TYP) || ((rtinfo->rt_type == rh->type) ^ !!(rtinfo->invflags & IP6T_RT_INV_TYP))); if (ret && (rtinfo->flags & IP6T_RT_RES)) { const u_int32_t *rp; u_int32_t _reserved; rp = skb_header_pointer(skb, ptr + offsetof(struct rt0_hdr, reserved), sizeof(_reserved), &_reserved); ret = (*rp == 0); } pr_debug("#%d ", rtinfo->addrnr); if (!(rtinfo->flags & IP6T_RT_FST)) { return ret; } else if (rtinfo->flags & IP6T_RT_FST_NSTRICT) { pr_debug("Not strict "); if (rtinfo->addrnr > (unsigned int)((hdrlen - 8) / 16)) { pr_debug("There isn't enough space\n"); return false; } else { unsigned int i = 0; pr_debug("#%d ", rtinfo->addrnr); for (temp = 0; temp < (unsigned int)((hdrlen - 8) / 16); temp++) { ap = skb_header_pointer(skb, ptr + sizeof(struct rt0_hdr) + temp * sizeof(_addr), sizeof(_addr), &_addr); BUG_ON(ap == NULL); if (ipv6_addr_equal(ap, &rtinfo->addrs[i])) { pr_debug("i=%d temp=%d;\n", i, temp); i++; } if (i == rtinfo->addrnr) break; } pr_debug("i=%d #%d\n", i, rtinfo->addrnr); if (i == rtinfo->addrnr) return ret; else return false; } } else { pr_debug("Strict "); if (rtinfo->addrnr > (unsigned int)((hdrlen - 8) / 16)) { pr_debug("There isn't enough space\n"); return false; } else { pr_debug("#%d ", rtinfo->addrnr); for (temp = 0; temp < rtinfo->addrnr; temp++) { ap = skb_header_pointer(skb, ptr + sizeof(struct rt0_hdr) + temp * sizeof(_addr), sizeof(_addr), &_addr); BUG_ON(ap == NULL); if (!ipv6_addr_equal(ap, &rtinfo->addrs[temp])) break; } pr_debug("temp=%d #%d\n", temp, rtinfo->addrnr); if (temp == rtinfo->addrnr && temp == (unsigned int)((hdrlen - 8) / 16)) return ret; else return false; } } return false; }

Contributors

PersonTokensPropCommitsCommitProp
harald welteharald welte67173.33%15.88%
yasuyuki kozakaiyasuyuki kozakai15216.61%317.65%
patrick mchardypatrick mchardy404.37%317.65%
jan engelhardtjan engelhardt363.93%741.18%
brian haleybrian haley90.98%15.88%
hans schillstromhans schillstrom40.44%15.88%
hideaki yoshifujihideaki yoshifuji30.33%15.88%
Total915100.00%17100.00%


static int rt_mt6_check(const struct xt_mtchk_param *par) { const struct ip6t_rt *rtinfo = par->matchinfo; if (rtinfo->invflags & ~IP6T_RT_INV_MASK) { pr_debug("unknown flags %X\n", rtinfo->invflags); return -EINVAL; } if ((rtinfo->flags & (IP6T_RT_RES | IP6T_RT_FST_MASK)) && (!(rtinfo->flags & IP6T_RT_TYP) || (rtinfo->rt_type != 0) || (rtinfo->invflags & IP6T_RT_INV_TYP))) { pr_debug("`--rt-type 0' required before `--rt-0-*'"); return -EINVAL; } return 0; }

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PersonTokensPropCommitsCommitProp
harald welteharald welte8584.16%112.50%
jan engelhardtjan engelhardt1211.88%562.50%
patrick mchardypatrick mchardy43.96%225.00%
Total101100.00%8100.00%

static struct xt_match rt_mt6_reg __read_mostly = { .name = "rt", .family = NFPROTO_IPV6, .match = rt_mt6, .matchsize = sizeof(struct ip6t_rt), .checkentry = rt_mt6_check, .me = THIS_MODULE, };
static int __init rt_mt6_init(void) { return xt_register_match(&rt_mt6_reg); }

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harald welteharald welte1381.25%133.33%
jan engelhardtjan engelhardt318.75%266.67%
Total16100.00%3100.00%


static void __exit rt_mt6_exit(void) { xt_unregister_match(&rt_mt6_reg); }

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harald welteharald welte1280.00%133.33%
jan engelhardtjan engelhardt320.00%266.67%
Total15100.00%3100.00%

module_init(rt_mt6_init); module_exit(rt_mt6_exit);

Overall Contributors

PersonTokensPropCommitsCommitProp
harald welteharald welte90474.04%26.90%
yasuyuki kozakaiyasuyuki kozakai15212.45%310.34%
jan engelhardtjan engelhardt806.55%1448.28%
patrick mchardypatrick mchardy564.59%620.69%
art haasart haas131.06%13.45%
brian haleybrian haley90.74%13.45%
hans schillstromhans schillstrom40.33%13.45%
hideaki yoshifujihideaki yoshifuji30.25%13.45%
Total1221100.00%29100.00%
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