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authorHenryk Plötz <henryk@ploetzli.ch>2014-10-03 20:04:14 +0200
committerHenryk Plötz <henryk@ploetzli.ch>2014-10-03 20:04:14 +0200
commitc44d8b51ffb5a413f8bbdbd9991bbc573853e397 (patch)
treee7f2e644de620879f610c909c405cbc4e44d6062 /ip6_scan.c
parent0e5b2871ca6456b01d4bf037a6e68badf1ff1a41 (diff)
downloadtinydnssec-c44d8b51ffb5a413f8bbdbd9991bbc573853e397.tar.gz
tinydnssec-c44d8b51ffb5a413f8bbdbd9991bbc573853e397.tar.bz2
Apply patch djbdns-1.05-test27.diff.bz2
Source was http://www.fefe.de/dns/djbdns-1.05-test27.diff.bz2, SHA1 f0380ec1866f49c0bcf6369a923ac0a4a5095da8
Diffstat (limited to 'ip6_scan.c')
-rw-r--r--ip6_scan.c115
1 files changed, 115 insertions, 0 deletions
diff --git a/ip6_scan.c b/ip6_scan.c
new file mode 100644
index 0000000..f355d46
--- /dev/null
+++ b/ip6_scan.c
@@ -0,0 +1,115 @@
+#include "scan.h"
+#include "ip4.h"
+#include "ip6.h"
+#include "byte.h"
+
+/*
+ * IPv6 addresses are really ugly to parse.
+ * Syntax: (h = hex digit)
+ * 1. hhhh:hhhh:hhhh:hhhh:hhhh:hhhh:hhhh:hhhh
+ * 2. any number of 0000 may be abbreviated as "::", but only once
+ * 3. The last two words may be written as IPv4 address
+ */
+
+unsigned int ip6_scan(const char *s,char ip[16])
+{
+ unsigned int i;
+ unsigned int len=0;
+ unsigned long u;
+
+ char suffix[16];
+ int prefixlen=0;
+ int suffixlen=0;
+
+ if ((i=ip4_scan(s,ip+12))) {
+ const char *c=V4mappedprefix;
+ if (byte_equal(ip+12,4,V6any)) c=V6any;
+ for (len=0; len<12; ++len) ip[len]=c[len];
+ return i;
+ }
+ for (i=0; i<16; i++) ip[i]=0;
+ for (;;) {
+ if (*s == ':') {
+ len++;
+ if (s[1] == ':') { /* Found "::", skip to part 2 */
+ s+=2;
+ len++;
+ break;
+ }
+ s++;
+ }
+ i = scan_xlong(s,&u);
+ if (!i) return 0;
+ if (prefixlen==12 && s[i]=='.') {
+ /* the last 4 bytes may be written as IPv4 address */
+ i=ip4_scan(s,ip+12);
+ if (i)
+ return i+len;
+ else
+ return 0;
+ }
+ ip[prefixlen++] = (u >> 8);
+ ip[prefixlen++] = (u & 255);
+ s += i; len += i;
+ if (prefixlen==16)
+ return len;
+ }
+
+/* part 2, after "::" */
+ for (;;) {
+ if (*s == ':') {
+ if (suffixlen==0)
+ break;
+ s++;
+ len++;
+ } else if (suffixlen!=0)
+ break;
+ i = scan_xlong(s,&u);
+ if (!i) {
+ len--;
+ break;
+ }
+ if (suffixlen+prefixlen<=12 && s[i]=='.') {
+ int j=ip4_scan(s,suffix+suffixlen);
+ if (j) {
+ suffixlen+=4;
+ len+=j;
+ break;
+ } else
+ prefixlen=12-suffixlen; /* make end-of-loop test true */
+ }
+ suffix[suffixlen++] = (u >> 8);
+ suffix[suffixlen++] = (u & 255);
+ s += i; len += i;
+ if (prefixlen+suffixlen==16)
+ break;
+ }
+ for (i=0; i<suffixlen; i++)
+ ip[16-suffixlen+i] = suffix[i];
+ return len;
+}
+
+static long int fromhex(unsigned char c) {
+ if (c>='0' && c<='9')
+ return c-'0';
+ else if (c>='A' && c<='F')
+ return c-'A'+10;
+ else if (c>='a' && c<='f')
+ return c-'a'+10;
+ return -1;
+}
+
+unsigned int ip6_scan_flat(const char *s,char ip[16])
+{
+ int i;
+ for (i=0; i<16; i++) {
+ int tmp;
+ tmp=fromhex(*s++);
+ if (tmp<0) return 0;
+ ip[i]=tmp << 4;
+ tmp=fromhex(*s++);
+ if (tmp<0) return 0;
+ ip[i]+=tmp;
+ }
+ return 32;
+}