X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/feb50f848364f748a2d5f31f9e65d50df37a0bcf..01cd3621f1ded1d0ec5cb55a87bcc3d735d59422:/print-mptcp.c diff --git a/print-mptcp.c b/print-mptcp.c index 17be82fa..8cca477e 100644 --- a/print-mptcp.c +++ b/print-mptcp.c @@ -32,81 +32,203 @@ * SUCH DAMAGE. */ +/* \summary: Multipath TCP (MPTCP) printer */ + +/* specification: RFC 6824 */ + #ifdef HAVE_CONFIG_H #include "config.h" #endif -#include +#include -#include -#include - -#include "interface.h" +#include "netdissect.h" #include "extract.h" #include "addrtoname.h" -#include "ipproto.h" -#include "mptcp.h" #include "tcp.h" -static int dummy_print(const u_char *opt _U_, u_int opt_len _U_, u_char flags _U_) +#define MPTCP_SUB_CAPABLE 0x0 +#define MPTCP_SUB_JOIN 0x1 +#define MPTCP_SUB_DSS 0x2 +#define MPTCP_SUB_ADD_ADDR 0x3 +#define MPTCP_SUB_REMOVE_ADDR 0x4 +#define MPTCP_SUB_PRIO 0x5 +#define MPTCP_SUB_FAIL 0x6 +#define MPTCP_SUB_FCLOSE 0x7 + +struct mptcp_option { + uint8_t kind; + uint8_t len; + uint8_t sub_etc; /* subtype upper 4 bits, other stuff lower 4 bits */ +}; + +#define MPTCP_OPT_SUBTYPE(sub_etc) (((sub_etc) >> 4) & 0xF) + +struct mp_capable { + uint8_t kind; + uint8_t len; + uint8_t sub_ver; + uint8_t flags; + uint8_t sender_key[8]; + uint8_t receiver_key[8]; +}; + +#define MP_CAPABLE_OPT_VERSION(sub_ver) (((sub_ver) >> 0) & 0xF) +#define MP_CAPABLE_C 0x80 +#define MP_CAPABLE_S 0x01 + +struct mp_join { + uint8_t kind; + uint8_t len; + uint8_t sub_b; + uint8_t addr_id; + union { + struct { + uint8_t token[4]; + uint8_t nonce[4]; + } syn; + struct { + uint8_t mac[8]; + uint8_t nonce[4]; + } synack; + struct { + uint8_t mac[20]; + } ack; + } u; +}; + +#define MP_JOIN_B 0x01 + +struct mp_dss { + uint8_t kind; + uint8_t len; + uint8_t sub; + uint8_t flags; +}; + +#define MP_DSS_F 0x10 +#define MP_DSS_m 0x08 +#define MP_DSS_M 0x04 +#define MP_DSS_a 0x02 +#define MP_DSS_A 0x01 + +struct mp_add_addr { + uint8_t kind; + uint8_t len; + uint8_t sub_ipver; + uint8_t addr_id; + union { + struct { + uint8_t addr[4]; + uint8_t port[2]; + } v4; + struct { + uint8_t addr[16]; + uint8_t port[2]; + } v6; + } u; +}; + +#define MP_ADD_ADDR_IPVER(sub_ipver) (((sub_ipver) >> 0) & 0xF) + +struct mp_remove_addr { + uint8_t kind; + uint8_t len; + uint8_t sub; + /* list of addr_id */ + uint8_t addrs_id; +}; + +struct mp_fail { + uint8_t kind; + uint8_t len; + uint8_t sub; + uint8_t resv; + uint8_t data_seq[8]; +}; + +struct mp_close { + uint8_t kind; + uint8_t len; + uint8_t sub; + uint8_t rsv; + uint8_t key[8]; +}; + +struct mp_prio { + uint8_t kind; + uint8_t len; + uint8_t sub_b; + uint8_t addr_id; +}; + +#define MP_PRIO_B 0x01 + +static int +dummy_print(netdissect_options *ndo _U_, + const u_char *opt _U_, u_int opt_len _U_, u_char flags _U_) { return 1; } -static int mp_capable_print(const u_char *opt, u_int opt_len, u_char flags) +static int +mp_capable_print(netdissect_options *ndo, + const u_char *opt, u_int opt_len, u_char flags) { - struct mp_capable *mpc = (struct mp_capable *) opt; + const struct mp_capable *mpc = (const struct mp_capable *) opt; - if (!(opt_len == 12 && flags & TH_SYN) && + if (!(opt_len == 12 && (flags & TH_SYN)) && !(opt_len == 20 && (flags & (TH_SYN | TH_ACK)) == TH_ACK)) return 0; if (MP_CAPABLE_OPT_VERSION(mpc->sub_ver) != 0) { - printf(" Unknown Version (%d)", MP_CAPABLE_OPT_VERSION(mpc->sub_ver)); + ND_PRINT((ndo, " Unknown Version (%d)", MP_CAPABLE_OPT_VERSION(mpc->sub_ver))); return 1; } if (mpc->flags & MP_CAPABLE_C) - printf(" csum"); - printf(" {0x%" PRIx64, EXTRACT_64BITS(mpc->sender_key)); + ND_PRINT((ndo, " csum")); + ND_PRINT((ndo, " {0x%" PRIx64, EXTRACT_BE_64BITS(mpc->sender_key))); if (opt_len == 20) /* ACK */ - printf(",0x%" PRIx64, EXTRACT_64BITS(mpc->receiver_key)); - printf("}"); + ND_PRINT((ndo, ",0x%" PRIx64, EXTRACT_BE_64BITS(mpc->receiver_key))); + ND_PRINT((ndo, "}")); return 1; } -static int mp_join_print(const u_char *opt, u_int opt_len, u_char flags) +static int +mp_join_print(netdissect_options *ndo, + const u_char *opt, u_int opt_len, u_char flags) { - struct mp_join *mpj = (struct mp_join *) opt; + const struct mp_join *mpj = (const struct mp_join *) opt; - if (!(opt_len == 12 && flags & TH_SYN) && + if (!(opt_len == 12 && (flags & TH_SYN)) && !(opt_len == 16 && (flags & (TH_SYN | TH_ACK)) == (TH_SYN | TH_ACK)) && - !(opt_len == 24 && flags & TH_ACK)) + !(opt_len == 24 && (flags & TH_ACK))) return 0; if (opt_len != 24) { if (mpj->sub_b & MP_JOIN_B) - printf(" backup"); - printf(" id %u", mpj->addr_id); + ND_PRINT((ndo, " backup")); + ND_PRINT((ndo, " id %u", mpj->addr_id)); } switch (opt_len) { case 12: /* SYN */ - printf(" token 0x%x" " nonce 0x%x", - EXTRACT_32BITS(mpj->u.syn.token), - EXTRACT_32BITS(mpj->u.syn.nonce)); + ND_PRINT((ndo, " token 0x%x" " nonce 0x%x", + EXTRACT_BE_32BITS(mpj->u.syn.token), + EXTRACT_BE_32BITS(mpj->u.syn.nonce))); break; case 16: /* SYN/ACK */ - printf(" hmac 0x%" PRIx64 " nonce 0x%x", - EXTRACT_64BITS(mpj->u.synack.mac), - EXTRACT_32BITS(mpj->u.synack.nonce)); + ND_PRINT((ndo, " hmac 0x%" PRIx64 " nonce 0x%x", + EXTRACT_BE_64BITS(mpj->u.synack.mac), + EXTRACT_BE_32BITS(mpj->u.synack.nonce))); break; case 24: {/* ACK */ size_t i; - printf(" hmac 0x"); + ND_PRINT((ndo, " hmac 0x")); for (i = 0; i < sizeof(mpj->u.ack.mac); ++i) - printf("%02x", mpj->u.ack.mac[i]); + ND_PRINT((ndo, "%02x", mpj->u.ack.mac[i])); } default: break; @@ -114,99 +236,117 @@ static int mp_join_print(const u_char *opt, u_int opt_len, u_char flags) return 1; } -static u_int mp_dss_len(struct mp_dss *m, int csum) +static int +mp_dss_print(netdissect_options *ndo, + const u_char *opt, u_int opt_len, u_char flags) { - u_int len; + const struct mp_dss *mdss = (const struct mp_dss *) opt; - len = 4; - if (m->flags & MP_DSS_A) { - /* Ack present - 4 or 8 octets */ - len += (m->flags & MP_DSS_a) ? 8 : 4; - } - if (m->flags & MP_DSS_M) { - /* - * Data Sequence Number (DSN), Subflow Sequence Number (SSN), - * Data-Level Length present, and Checksum possibly present. - * All but the Checksum are 10 bytes if the m flag is - * clear (4-byte DSN) and 14 bytes if the m flag is set - * (8-byte DSN). - */ - len += (m->flags & MP_DSS_m) ? 14 : 10; - - /* - * The Checksum is present only if negotiated. - */ - if (csum) - len += 2; - } - return len; -} - -static int mp_dss_print(const u_char *opt, u_int opt_len, u_char flags) -{ - struct mp_dss *mdss = (struct mp_dss *) opt; + /* We need the flags, at a minimum. */ + if (opt_len < 4) + return 0; - if ((opt_len != mp_dss_len(mdss, 1) && - opt_len != mp_dss_len(mdss, 0)) || flags & TH_SYN) + if (flags & TH_SYN) return 0; if (mdss->flags & MP_DSS_F) - printf(" fin"); + ND_PRINT((ndo, " fin")); opt += 4; + opt_len -= 4; if (mdss->flags & MP_DSS_A) { - printf(" ack "); + /* Ack present */ + ND_PRINT((ndo, " ack ")); + /* + * If the a flag is set, we have an 8-byte ack; if it's + * clear, we have a 4-byte ack. + */ if (mdss->flags & MP_DSS_a) { - printf("%" PRIu64, EXTRACT_64BITS(opt)); + if (opt_len < 8) + return 0; + ND_PRINT((ndo, "%" PRIu64, EXTRACT_BE_64BITS(opt))); opt += 8; + opt_len -= 8; } else { - printf("%u", EXTRACT_32BITS(opt)); + if (opt_len < 4) + return 0; + ND_PRINT((ndo, "%u", EXTRACT_BE_32BITS(opt))); opt += 4; + opt_len -= 4; } } if (mdss->flags & MP_DSS_M) { - printf(" seq "); + /* + * Data Sequence Number (DSN), Subflow Sequence Number (SSN), + * Data-Level Length present, and Checksum possibly present. + */ + ND_PRINT((ndo, " seq ")); + /* + * If the m flag is set, we have an 8-byte NDS; if it's clear, + * we have a 4-byte DSN. + */ if (mdss->flags & MP_DSS_m) { - printf("%" PRIu64, EXTRACT_64BITS(opt)); + if (opt_len < 8) + return 0; + ND_PRINT((ndo, "%" PRIu64, EXTRACT_BE_64BITS(opt))); opt += 8; + opt_len -= 8; } else { - printf("%u", EXTRACT_32BITS(opt)); + if (opt_len < 4) + return 0; + ND_PRINT((ndo, "%u", EXTRACT_BE_32BITS(opt))); opt += 4; + opt_len -= 4; } - printf(" subseq %u", EXTRACT_32BITS(opt)); + if (opt_len < 4) + return 0; + ND_PRINT((ndo, " subseq %u", EXTRACT_BE_32BITS(opt))); opt += 4; - printf(" len %u", EXTRACT_16BITS(opt)); + opt_len -= 4; + if (opt_len < 2) + return 0; + ND_PRINT((ndo, " len %u", EXTRACT_BE_16BITS(opt))); opt += 2; + opt_len -= 2; - if (opt_len == mp_dss_len(mdss, 1)) - printf(" csum 0x%x", EXTRACT_16BITS(opt)); + /* + * The Checksum is present only if negotiated. + * If there are at least 2 bytes left, process the next 2 + * bytes as the Checksum. + */ + if (opt_len >= 2) { + ND_PRINT((ndo, " csum 0x%x", EXTRACT_BE_16BITS(opt))); + opt_len -= 2; + } } + if (opt_len != 0) + return 0; return 1; } -static int add_addr_print(const u_char *opt, u_int opt_len, u_char flags _U_) +static int +add_addr_print(netdissect_options *ndo, + const u_char *opt, u_int opt_len, u_char flags _U_) { - struct mp_add_addr *add_addr = (struct mp_add_addr *) opt; + const struct mp_add_addr *add_addr = (const struct mp_add_addr *) opt; u_int ipver = MP_ADD_ADDR_IPVER(add_addr->sub_ipver); if (!((opt_len == 8 || opt_len == 10) && ipver == 4) && !((opt_len == 20 || opt_len == 22) && ipver == 6)) return 0; - printf(" id %u", add_addr->addr_id); + ND_PRINT((ndo, " id %u", add_addr->addr_id)); switch (ipver) { case 4: - printf(" %s", ipaddr_string(add_addr->u.v4.addr)); + ND_PRINT((ndo, " %s", ipaddr_string(ndo, add_addr->u.v4.addr))); if (opt_len == 10) - printf(":%u", EXTRACT_16BITS(add_addr->u.v4.port)); + ND_PRINT((ndo, ":%u", EXTRACT_BE_16BITS(add_addr->u.v4.port))); break; case 6: -#ifdef INET6 - printf(" %s", ip6addr_string(add_addr->u.v6.addr)); -#endif + ND_PRINT((ndo, " %s", ip6addr_string(ndo, add_addr->u.v6.addr))); if (opt_len == 22) - printf(":%u", EXTRACT_16BITS(add_addr->u.v6.port)); + ND_PRINT((ndo, ":%u", EXTRACT_BE_16BITS(add_addr->u.v6.port))); break; default: return 0; @@ -215,59 +355,69 @@ static int add_addr_print(const u_char *opt, u_int opt_len, u_char flags _U_) return 1; } -static int remove_addr_print(const u_char *opt, u_int opt_len, u_char flags _U_) +static int +remove_addr_print(netdissect_options *ndo, + const u_char *opt, u_int opt_len, u_char flags _U_) { - struct mp_remove_addr *remove_addr = (struct mp_remove_addr *) opt; - u_int8_t *addr_id = &remove_addr->addrs_id; + const struct mp_remove_addr *remove_addr = (const struct mp_remove_addr *) opt; + const uint8_t *addr_id = &remove_addr->addrs_id; if (opt_len < 4) return 0; opt_len -= 3; - printf(" id"); - while (opt_len--) - printf(" %u", *addr_id++); + ND_PRINT((ndo, " id")); + while (opt_len--) { + ND_PRINT((ndo, " %u", EXTRACT_8BITS(addr_id))); + addr_id++; + } return 1; } -static int mp_prio_print(const u_char *opt, u_int opt_len, u_char flags _U_) +static int +mp_prio_print(netdissect_options *ndo, + const u_char *opt, u_int opt_len, u_char flags _U_) { - struct mp_prio *mpp = (struct mp_prio *) opt; + const struct mp_prio *mpp = (const struct mp_prio *) opt; if (opt_len != 3 && opt_len != 4) return 0; if (mpp->sub_b & MP_PRIO_B) - printf(" backup"); + ND_PRINT((ndo, " backup")); else - printf(" non-backup"); + ND_PRINT((ndo, " non-backup")); if (opt_len == 4) - printf(" id %u", mpp->addr_id); + ND_PRINT((ndo, " id %u", mpp->addr_id)); return 1; } -static int mp_fail_print(const u_char *opt, u_int opt_len, u_char flags _U_) +static int +mp_fail_print(netdissect_options *ndo, + const u_char *opt, u_int opt_len, u_char flags _U_) { if (opt_len != 12) return 0; - printf(" seq %" PRIu64, EXTRACT_64BITS(opt + 4)); + ND_PRINT((ndo, " seq %" PRIu64, EXTRACT_BE_64BITS(opt + 4))); return 1; } -static int mp_fast_close_print(const u_char *opt, u_int opt_len, u_char flags _U_) +static int +mp_fast_close_print(netdissect_options *ndo, + const u_char *opt, u_int opt_len, u_char flags _U_) { if (opt_len != 12) return 0; - printf(" key 0x%" PRIx64, EXTRACT_64BITS(opt + 4)); + ND_PRINT((ndo, " key 0x%" PRIx64, EXTRACT_BE_64BITS(opt + 4))); return 1; } -static struct { +static const struct { const char *name; - int (*print)(const u_char *, u_int, u_char); + int (*print)(netdissect_options *, const u_char *, u_int, u_char); } mptcp_options[] = { { "capable", mp_capable_print}, { "join", mp_join_print }, @@ -280,17 +430,19 @@ static struct { { "unknown", dummy_print }, }; -int mptcp_print(const u_char *cp, u_int len, u_char flags) +int +mptcp_print(netdissect_options *ndo, + const u_char *cp, u_int len, u_char flags) { - struct mptcp_option *opt; + const struct mptcp_option *opt; u_int subtype; if (len < 3) return 0; - opt = (struct mptcp_option *) cp; + opt = (const struct mptcp_option *) cp; subtype = min(MPTCP_OPT_SUBTYPE(opt->sub_etc), MPTCP_SUB_FCLOSE + 1); - printf(" %s", mptcp_options[subtype].name); - return mptcp_options[subtype].print(cp, len, flags); + ND_PRINT((ndo, " %s", mptcp_options[subtype].name)); + return mptcp_options[subtype].print(ndo, cp, len, flags); }