diff options
Diffstat (limited to 'include/net/mld.h')
-rw-r--r-- | include/net/mld.h | 51 |
1 files changed, 43 insertions, 8 deletions
diff --git a/include/net/mld.h b/include/net/mld.h index 467143cd4e2f..faa1d161bf24 100644 --- a/include/net/mld.h +++ b/include/net/mld.h @@ -63,13 +63,48 @@ struct mld2_query { #define mld2q_mrc mld2q_hdr.icmp6_maxdelay #define mld2q_resv1 mld2q_hdr.icmp6_dataun.un_data16[1] -/* Max Response Code */ -#define MLDV2_MASK(value, nb) ((nb)>=32 ? (value) : ((1<<(nb))-1) & (value)) -#define MLDV2_EXP(thresh, nbmant, nbexp, value) \ - ((value) < (thresh) ? (value) : \ - ((MLDV2_MASK(value, nbmant) | (1<<(nbmant))) << \ - (MLDV2_MASK((value) >> (nbmant), nbexp) + (nbexp)))) - -#define MLDV2_MRC(value) MLDV2_EXP(0x8000, 12, 3, value) +/* RFC3810, 5.1.3. Maximum Response Code: + * + * If Maximum Response Code >= 32768, Maximum Response Code represents a + * floating-point value as follows: + * + * 0 1 2 3 4 5 6 7 8 9 A B C D E F + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + * |1| exp | mant | + * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + */ +#define MLDV2_MRC_EXP(value) (((value) >> 12) & 0x0007) +#define MLDV2_MRC_MAN(value) ((value) & 0x0fff) + +/* RFC3810, 5.1.9. QQIC (Querier's Query Interval Code): + * + * If QQIC >= 128, QQIC represents a floating-point value as follows: + * + * 0 1 2 3 4 5 6 7 + * +-+-+-+-+-+-+-+-+ + * |1| exp | mant | + * +-+-+-+-+-+-+-+-+ + */ +#define MLDV2_QQIC_EXP(value) (((value) >> 4) & 0x07) +#define MLDV2_QQIC_MAN(value) ((value) & 0x0f) + +static inline unsigned long mldv2_mrc(const struct mld2_query *mlh2) +{ + /* RFC3810, 5.1.3. Maximum Response Code */ + unsigned long ret, mc_mrc = ntohs(mlh2->mld2q_mrc); + + if (mc_mrc < 32768) { + ret = mc_mrc; + } else { + unsigned long mc_man, mc_exp; + + mc_exp = MLDV2_MRC_EXP(mc_mrc); + mc_man = MLDV2_MRC_MAN(mc_mrc); + + ret = (mc_man | 0x1000) << (mc_exp + 3); + } + + return ret; +} #endif |