ng_ipv6_addr: add string to address conversion function

sys/include/net/ng_ipv6/addr.h

@@ -520,6 +520,23 @@ static inline void ng_ipv6_addr_set_solicited_nodes(ng_ipv6_addr_t *out,
 char *ng_ipv6_addr_to_str(char *result, const ng_ipv6_addr_t *addr,
                           uint8_t result_len);
 
+/**
+ * @brief   Converts an IPv6 address string representation to a byte-represented
+ *          IPv6 address
+ *
+ * @see <a href="https://tools.ietf.org/html/rfc5952">
+ *          RFC 5952
+ *      </a>
+ *
+ * @param[in] result    The resulting byte representation
+ * @param[in] addr      An IPv6 address string representation
+ *
+ * @return  @p result, on success
+ * @return  NULL, if @p addr was malformed
+ * @return  NULL, if @p result or @p addr was NULL
+ */
+ng_ipv6_addr_t *ng_ipv6_addr_from_str(ng_ipv6_addr_t *result, const char *addr);
+
 #ifdef __cplusplus
 }
 #endif

sys/net/network_layer/ng_ipv6/addr/ng_ipv6_addr_from_str.c

@@ -0,0 +1,203 @@
+/*
+ * Copyright (c) 1996 by Internet Software Consortium.
+ * Copyright (c) 2015 by Martine Lenders <mlenders@inf.fu-berlin.de>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
+ * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
+ * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+ * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
+ * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
+ * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
+ * SOFTWARE.
+ */
+
+/**
+ * @ingroup     net_ipv6_addr
+ * @{
+ *
+ * @file
+ *
+ * @author      Paul Vixie
+ * @author      Martine Lenders <mlenders@inf.fu-berlin.de>
+ */
+
+#include <inttypes.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "byteorder.h"
+#include "net/ng_ipv6/addr.h"
+
+#define DEC     "0123456789"
+#define HEX_L   "0123456789abcdef"
+#define HEX_U   "0123456789ABCDEF"
+
+/* XXX: move this to IPv4 when we have it */
+/* based on inet_pton4() by Paul Vixie */
+static network_uint32_t *ipv4_addr_from_str(network_uint32_t *result,
+        const char *addr)
+{
+    uint8_t saw_digit, octets, ch;
+    uint8_t tmp[sizeof(network_uint32_t)], *tp;
+
+    saw_digit = 0;
+    octets = 0;
+    *(tp = tmp) = 0;
+
+    while ((ch = *addr++) != '\0') {
+        const char *pch;
+
+        if ((pch = strchr(DEC, ch)) != NULL) {
+            uint16_t new = *tp * 10 + (uint16_t)(pch - DEC);
+
+            if (new > 255) {
+                return NULL;
+            }
+
+            *tp = new;
+
+            if (!saw_digit) {
+                if (++octets > 4) {
+                    return NULL;
+                }
+
+                saw_digit = 1;
+            }
+        }
+        else if (ch == '.' && saw_digit) {
+            if (octets == 4) {
+                return NULL;
+            }
+
+            *++tp = 0;
+            saw_digit = 0;
+        }
+        else {
+            return NULL;
+        }
+    }
+
+    if (octets < 4) {
+        return NULL;
+    }
+
+    memcpy(result, tmp, sizeof(network_uint32_t));
+    return result;
+}
+
+/* based on inet_pton6() by Paul Vixie */
+ng_ipv6_addr_t *ng_ipv6_addr_from_str(ng_ipv6_addr_t *result, const char *addr)
+{
+    uint8_t *colonp = 0;
+    const char *curtok = addr;
+    uint32_t val = 0;
+    char ch;
+    uint8_t saw_xdigit = 0;
+    uint8_t i = 0;
+
+    if ((result == NULL) || (addr == NULL)) {
+        return NULL;
+    }
+
+    ng_ipv6_addr_set_unspecified(result);
+
+    /* Leading :: requires some special handling. */
+    if (*addr == ':') {
+        if (*++addr != ':') {
+            return NULL;
+        }
+    }
+
+    while ((ch = *addr++) != '\0') {
+        const char *pch;
+        const char *xdigits;
+
+        if ((pch = strchr((xdigits = HEX_L), ch)) == NULL) {
+            pch = strchr((xdigits = HEX_U), ch);
+        }
+
+        if (pch != NULL) {
+            val <<= 4;
+            val |= (pch - xdigits);
+
+            if (val > 0xffff) {
+                return NULL;
+            }
+
+            saw_xdigit = 1;
+            continue;
+        }
+
+        if (ch == ':') {
+            curtok = addr;
+
+            if (!saw_xdigit) {
+                if (colonp != NULL) {
+                    return NULL;
+                }
+
+                colonp = &(result->u8[i]);
+                continue;
+            }
+
+            if (i > sizeof(ng_ipv6_addr_t)) {
+                return NULL;
+            }
+
+            result->u8[i++] = (uint8_t)(val >> 8) & 0xff;
+            result->u8[i++] = (uint8_t) val & 0xff;
+            saw_xdigit = 0;
+            val = 0;
+            continue;
+        }
+
+        if (ch == '.' && (i <= sizeof(ng_ipv6_addr_t)) &&
+            ipv4_addr_from_str((network_uint32_t *)(&(result->u8[i])),
+                               curtok) != NULL) {
+            i += sizeof(network_uint32_t);
+            saw_xdigit = 0;
+            break;  /* '\0' was seen by ipv4_addr_from_str(). */
+        }
+
+        return NULL;
+    }
+
+    if (saw_xdigit) {
+        if (i + sizeof(uint16_t) > sizeof(ng_ipv6_addr_t)) {
+            return NULL;
+        }
+
+        result->u8[i++] = (uint8_t)(val >> 8) & 0xff;
+        result->u8[i++] = (uint8_t) val & 0xff;
+    }
+
+    if (colonp != NULL) {
+        /*
+         * Since some memmove()'s erroneously fail to handle
+         * overlapping regions, we'll do the shift by hand.
+         */
+        const int32_t n = &(result->u8[i++]) - colonp;
+
+        for (int32_t j = 1; j <= n; j++) {
+            result->u8[sizeof(ng_ipv6_addr_t) - j] = colonp[n - j];
+            colonp[n - j] = 0;
+        }
+
+        i = sizeof(ng_ipv6_addr_t);
+    }
+
+    if (i != sizeof(ng_ipv6_addr_t)) {
+        return NULL;
+    }
+
+    return result;
+}
+
+/**
+ * @}
+ */