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-rw-r--r--src/ip6.c350
1 files changed, 350 insertions, 0 deletions
diff --git a/src/ip6.c b/src/ip6.c
new file mode 100644
index 0000000..a5a60fd
--- /dev/null
+++ b/src/ip6.c
@@ -0,0 +1,350 @@
+#include "fmt.h"
+#include "byte.h"
+#include "scan.h"
+#include "ip.h"
+#include "str.h"
+
+/**
+ * @file ip6.c
+ * @authors djb, fefe, feh
+ * @ref ucspi-tcp, ucspi-tcp6
+ * @brief handling of IPv6 addresses
+ */
+
+/**
+ * @brief ip6_fmt
+ * convert IPv6 address to compactified IPv6 address string
+ * @param input: IPv6 char array
+ * output: pointer to IPv6 address string
+ * @return int length of address (ok > 0)
+ */
+unsigned int ip6_fmt(char *s,char ip[16])
+{
+ unsigned int len;
+ unsigned int i;
+ unsigned int temp, temp0;
+ unsigned int compressing;
+ unsigned int compressed;
+ int j;
+
+ len = 0;
+ compressing = 0;
+ compressed = 0;
+
+ for (j = 0; j < 16; j += 2) {
+ if (j == 12 && ip6_isv4mapped(ip)) {
+ len += ip4_fmt(s,ip+12);
+ break;
+ }
+
+ temp = ((unsigned long) (unsigned char) ip[j] << 8) +
+ (unsigned long) (unsigned char) ip[j+1];
+
+ temp0 = 0;
+ if (!compressing && j < 16)
+ temp0 = ((unsigned long) (unsigned char) ip[j+2] << 8) +
+ (unsigned long) (unsigned char) ip[j+3];
+
+ if (temp == 0 && temp0 == 0 && !compressed) {
+ if (!compressing) {
+ compressing = 1;
+ if (j == 0) {
+ if (s) *s++ = ':';
+ ++len;
+ }
+ }
+ } else {
+ if (compressing) {
+ compressing = 0;
+ ++compressed;
+ if (s) *s++ = ':';
+ ++len;
+ }
+ i = fmt_xlong(s,temp);
+ len += i;
+ if (s) s += i;
+ if (j < 14) {
+ if (s) *s++ = ':';
+ ++len;
+ }
+ }
+ }
+ if (compressing) { *s++ = ':'; ++len; }
+
+ return len;
+}
+
+/**
+ * @brief ip6_fmt_flat
+ * convert IPv6 address to IPv6 address string
+ * @param input: IPv6 char array
+ * output: pointer to IPv6 address string
+ * @return int length of address (ok > 0)
+ */
+unsigned int ip6_fmt_flat(char *s,char ip[16])
+{
+ int i;
+ for (i = 0; i < 16; i++) {
+ *s++ = tohex((unsigned char)ip[i] >> 4);
+ *s++ = tohex((unsigned char)ip[i] & 15);
+ }
+ return 32;
+}
+
+/**
+ * @brief ia6_fmt
+ * convert IPv6 address to inverse DNS nibble format
+ * 1.2.3.4.5.6.7.8.9.a.b.c.d.e.f.1.2.3.4.5.6.7.8.9.a.b.c.d.e.f.ip6.arpa
+ * @param input: IPv6 char array
+ * output: pointer to IPv6 address string
+ * @return int length of address
+ */
+unsigned int ia6_fmt(char *s,char ip[16])
+{
+ unsigned int i;
+ unsigned int len;
+ int j;
+
+ static char data[] = "0123456789abcdef";
+ len = 0;
+
+ for (j = 15; j >= 0; j--) {
+ i = fmt_str(s,&data[ip[j] & 0x0f]); len += i; if (s) s += i;
+ i = fmt_str(s,"."); len += i; if (s) s += i;
+ i = fmt_str(s,&data[ip[j] >> 4 & 0x0f]); len += i; if (s) s += i;
+ i = fmt_str(s,"."); len += i; if (s) s += i;
+ }
+ i = fmt_str(s,"ip6.arpa."); len += i; if (s) s += i;
+
+ return len;
+}
+
+/**
+ * @brief ip6_scan_flat
+ * convert IPv6 address string to IPv6 address array
+ * @param input: pointer to IPv6 address string
+ * output: IPv6 char array
+ * @return int length of address (ok > 0)
+ */
+unsigned int ip6_scan_flat(const char *s,char ip[16])
+{
+ int i, tmp;
+
+ for (i = 0; i < 16; i++) {
+ 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;
+}
+
+/**
+ * @brief ip6_scan
+ * parse compactified IPv6 address string and convert to IPv6 address array
+ * @param input: pointer to IPv6 address string
+ * output: IPv6 char array
+ * @return int length of ip6_address/ip
+ */
+unsigned int ip6_scan(const char *s,char ip[16])
+{
+ unsigned int i, j;
+ unsigned int len = 0;
+ unsigned long u;
+
+ char suffix[16];
+ int prefixlen = 0;
+ int suffixlen = 0;
+
+ /* Always return IPv4 as IPv4-mapped IPv6 address */
+ if ((i = ip4_scan(s,ip+12))) {
+ for (len = 0; len < 12; ++len)
+ ip[len] = V4mappedprefix[len];
+ return i;
+ if (byte_equal(ip+12,4,V4localnet)) {
+ byte_copy(ip,16,V6localnet);
+ return 16;
+ }
+ }
+ byte_zero(ip,16);
+
+ for (;;) {
+ if (*s == ':') {
+ len++;
+ if (s[1] == ':') { /* Found "::", skip to part 2 */
+ s += 2; len++;
+ break;
+ }
+ s++;
+ }
+ i = scan_xlong((char *)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((char *)s,&u);
+ if (!i) {
+ len--;
+ break;
+ }
+
+ if (suffixlen + prefixlen <= 12 && s[i] == '.') {
+ 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;
+}
+
+/**
+ * @brief ip6_scanbracket
+ * parse IPv6 string address enclosed in brackets
+ * @param input: pointer to IPv6 address string
+ * output: IPv6 char array
+ * @return int length of ip_address (ok > 0)
+ */
+unsigned int ip6_scanbracket(const char *s,char ip[16])
+{
+ unsigned int len;
+
+ if (*s != '[') return 0;
+ len = ip6_scan(s + 1,ip);
+ if (!len) return 0;
+ if (s[len + 1] != ']') return 0;
+ return len + 2;
+}
+
+/**
+ * @brief ip6_ifscan
+ * parse compactified IPv6 address string
+ * concatinated with the interface name: fe80::1%eth0
+ * @param input: pointer to IPv6 address string
+ * output: IPv6 char array, stralloc interface_name
+ * @return int length of ip6_address/ip
+ */
+unsigned int ip6_ifscan(char *s,char ip[16],stralloc *ifname)
+{
+ int i;
+ int j = 0;
+ int k = 0;
+ if (!stralloc_copys(ifname,"0")) return 0;
+
+ if ((j = str_chr(s,'%'))) {
+ if ((i = str_chr(s+j+1,' '))) k = i;
+ else if ((i = str_chr(s+j+1,'\n'))) k = i;
+ else if ((i = str_chr(s+j+1,'\t'))) k = i;
+ if (k) s[j+k+1] = '\0'; /* input might contain trailing chars */
+ if (!stralloc_copys(ifname,s+j+1)) return 0;
+ s[j] = 0;
+ }
+ if (!stralloc_0(ifname)) return 0;
+
+ return ip6_scan(s,ip);
+}
+
+/**
+ * @brief ip6_cidr
+ * parse compactified IPv6 address string
+ * concatinated with the prefix length: fe80::1/64
+ * @param input: pointer to IPv6 address string
+ * output: IPv6 char array, long plen
+ * @return int length of ip6_address/ip
+ */
+unsigned int ip6_cidr(char *s,char ip[16],unsigned long *plen)
+{
+ unsigned int j = 0;
+ *plen = 128UL;
+
+ j = str_chr(s,'/');
+ if (s[j] == '/') {
+ s[j] = 0;
+ j = scan_ulong(s+j+1,plen);
+ }
+ return ip6_scan((const char *)s,ip);
+}
+
+/**
+ * @brief ip6_bytestring
+ * parse IPv6 address and represent as char string with length prefix
+ * @param input: IPv6 char array, prefix length
+ * output: pointer to stralloc bit string;
+ * @return n: number of bytes, if ok; -1: memory shortage
+ */
+unsigned int ip6_bytestring(stralloc *ipstring,char ip[16],int prefix)
+{
+ int i, j, n = 0;
+ unsigned char lowbyte, highbyte;
+
+ if (!stralloc_readyplus(ipstring,128)) return -1;
+ if (!stralloc_copys(ipstring,"")) return -1;
+
+ for (i = 0; i < 16; i++) {
+ lowbyte = (unsigned char) (ip[i]) & 0x0f;
+ highbyte = (unsigned char) (ip[i] >> 4) & 0x0f;
+
+ for (j = 3; j >= 0; j--) {
+ if (highbyte & (1 << j)) {
+ n++;
+ if (!stralloc_cats(ipstring,"1")) return -1;
+ } else {
+ n++;
+ if (!stralloc_cats(ipstring,"0")) return -1;
+ }
+ prefix--;
+ if (!prefix) goto DONE;
+ }
+ for (j = 3; j >= 0; j--) {
+ if (lowbyte & (1 << j)) {
+ n++;
+ if (!stralloc_cats(ipstring,"1")) return -1;
+ } else {
+ n++;
+ if (!stralloc_cats(ipstring,"0")) return -1;
+ }
+ prefix--;
+ if (!prefix) goto DONE;
+ }
+ }
+
+DONE:
+ if (!stralloc_0(ipstring)) return -1;
+
+ return n;
+}
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