diff options
Diffstat (limited to 'src/libstddjb/ip6_scan.c')
| -rw-r--r-- | src/libstddjb/ip6_scan.c | 96 |
1 files changed, 74 insertions, 22 deletions
diff --git a/src/libstddjb/ip6_scan.c b/src/libstddjb/ip6_scan.c index b0e5b56..d2cdad6 100644 --- a/src/libstddjb/ip6_scan.c +++ b/src/libstddjb/ip6_scan.c @@ -1,37 +1,89 @@ /* ISC license. */ -#include <errno.h> +#include <stdint.h> #include <skalibs/uint16.h> #include <skalibs/fmtscan.h> + +/* IPv6 scanner + +class | 0 1 2 3 +st\ev | other hex : . + +START | m +00 | X LIMB COLON1 X + +COLON1 | p +01 | X X NEW X + +NEW | m +02 | END LIMB X X + +LIMB | h h +03 | END LIMB COLON V4 + +COLON | m p +04 | X LIMB NEW X + + +END = 05 +V4 = 06 +X = 07 + +0x10 m mark +0x20 p set doublecolon pos +0x40 h scan hex, next limb + +*/ + size_t ip6_scan (char const *s, char *ip6) { - static unsigned char const class[256] = "2222222222222222222222222222222222222222222222220000000000122222200000022222222222222222222222222000000222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222" ; - static unsigned char const table[5][3] = { "\024#\005", "\024\"\005", "\024\005\006", "\005\002\005", "\024\t\016" } ; - uint16_t tmp[8] = { 0, 0, 0, 0, 0, 0, 0, 0 } ; - size_t i = 0 ; - unsigned int pos = 8, j = 0, state = 0 ; + static unsigned char const class[256] = "0000000000000000000000000000000000000000000000301111111111200000011111100000000000000000000000000111111000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" ; + static uint8_t const table[5][4] = + { + { 0x07, 0x13, 0x01, 0x07 }, + { 0x07, 0x07, 0x22, 0x07 }, + { 0x05, 0x13, 0x07, 0x07 }, + { 0x45, 0x03, 0x44, 0x06 }, + { 0x07, 0x13, 0x22, 0x07 } + } ; + size_t i = 0, mark = 0 ; + uint16_t limb[8] = { 0, 0, 0, 0, 0, 0, 0, 0 } ; + uint8_t pos = 8, j = 0, state = 0 ; - while (state < 5) + for (; state < 0x05 ; i++) { - unsigned char c = table[state][class[(unsigned char)s[i]] - '0'] ; - state = c & 7 ; - if (c & 0x20) { if (pos < 8) state = 5 ; else pos = j ; } - if (c & 0x10) + uint8_t c = table[state][class[(unsigned char)s[i]] - '0'] ; + state = c & 0x07 ; + if (c & 0x10) mark = i ; + if (c & 0x20) { if (pos < 8) state = 0x07 ; else pos = j ; } + if (c & 0x40) + if (j >= 8 || uint16_xscan(s + mark, limb + j++) != i - mark) state = 0x07 ; + } + + switch (state) + { + case 0x05: + if (pos == 8 && j < 8 || (pos < 8 && j > 6)) return 0 ; + i-- ; + break ; + case 0x06: { - if (tmp[j] & 0xf000) state = 5 ; - else tmp[j] = (tmp[j] << 4) + fmtscan_num(s[i], 16) ; + uint32_t ip4 ; + if (pos == 8 && j != 6 || (pos < 8 && j > 4)) return 0 ; + i = ip4_scanu32(s + mark, &ip4) ; + if (!i) return 0 ; + limb[j++] = ip4 >> 16 ; + limb[j++] = ip4 & 0xffff ; + i += mark ; + break ; } - if (c & 0x08) if ((++j > 7) && (state < 5)) state = 5 ; - i++ ; + default : return 0 ; } - if (((pos < 8) && (j > 6)) || ((pos == 8) && (j < 8))) state = 5 ; - if (state == 5) return (errno = EINVAL, 0) ; - for (state = j ; state > pos ; state--) tmp[state - j + 7] = tmp[state - 1] ; - for (; state < pos + 8 - j ; state++) tmp[state] = 0 ; - - for (j = 0 ; j < 8 ; j++) uint16_pack_big(ip6 + (j<<1), tmp[j]) ; - return i - 1 ; + for (state = j ; state > pos ; state--) limb[state - j + 7] = limb[state - 1] ; + for (; state < pos + 8 - j ; state++) limb[state] = 0 ; + for (j = 0 ; j < 8 ; j++) uint16_pack_big(ip6 + (j<<1), limb[j]) ; + return i ; } |