net: Split resolving out of CSubNet

1 files changed, 58 insertions, 36 deletions

diff --git a/src/netbase.cpp b/src/netbase.cpp
index 2e7a4f758a..52badcd98f 100644
--- a/src/netbase.cpp
+++ b/src/netbase.cpp
@@ -1214,63 +1214,85 @@ CSubNet::CSubNet():
     memset(netmask, 0, sizeof(netmask));
 }
 
-CSubNet::CSubNet(const std::string &strSubnet)
+CSubNet::CSubNet(const CNetAddr &addr, int32_t mask)
 {
-    size_t slash = strSubnet.find_last_of('/');
-    std::vector<CNetAddr> vIP;
+    valid = true;
+    network = addr;
+    // Default to /32 (IPv4) or /128 (IPv6), i.e. match single address
+    memset(netmask, 255, sizeof(netmask));
 
+    // IPv4 addresses start at offset 12, and first 12 bytes must match, so just offset n
+    const int astartofs = network.IsIPv4() ? 12 : 0;
+
+    int32_t n = mask;
+    if(n >= 0 && n <= (128 - astartofs*8)) // Only valid if in range of bits of address
+    {
+        n += astartofs*8;
+        // Clear bits [n..127]
+        for (; n < 128; ++n)
+            netmask[n>>3] &= ~(1<<(7-(n&7)));
+    } else
+        valid = false;
+
+    // Normalize network according to netmask
+    for(int x=0; x<16; ++x)
+        network.ip[x] &= netmask[x];
+}
+
+CSubNet::CSubNet(const CNetAddr &addr, const CNetAddr &mask)
+{
     valid = true;
+    network = addr;
     // Default to /32 (IPv4) or /128 (IPv6), i.e. match single address
     memset(netmask, 255, sizeof(netmask));
 
+    // IPv4 addresses start at offset 12, and first 12 bytes must match, so just offset n
+    const int astartofs = network.IsIPv4() ? 12 : 0;
+
+    for(int x=astartofs; x<16; ++x)
+        netmask[x] = mask.ip[x];
+
+    // Normalize network according to netmask
+    for(int x=0; x<16; ++x)
+        network.ip[x] &= netmask[x];
+}
+
+
+bool LookupSubNet(const char* pszName, CSubNet& ret)
+{
+    std::string strSubnet(pszName);
+    size_t slash = strSubnet.find_last_of('/');
+    std::vector<CNetAddr> vIP;
+
     std::string strAddress = strSubnet.substr(0, slash);
     if (LookupHost(strAddress.c_str(), vIP, 1, false))
     {
-        network = vIP[0];
+        CNetAddr network = vIP[0];
         if (slash != strSubnet.npos)
         {
             std::string strNetmask = strSubnet.substr(slash + 1);
             int32_t n;
             // IPv4 addresses start at offset 12, and first 12 bytes must match, so just offset n
-            const int astartofs = network.IsIPv4() ? 12 : 0;
-            if (ParseInt32(strNetmask, &n)) // If valid number, assume /24 symtex
-            {
-                if(n >= 0 && n <= (128 - astartofs*8)) // Only valid if in range of bits of address
-                {
-                    n += astartofs*8;
-                    // Clear bits [n..127]
-                    for (; n < 128; ++n)
-                        netmask[n>>3] &= ~(1<<(7-(n&7)));
-                }
-                else
-                {
-                    valid = false;
-                }
+            if (ParseInt32(strNetmask, &n)) { // If valid number, assume /24 syntax
+                ret = CSubNet(network, n);
+                return ret.IsValid();
             }
             else // If not a valid number, try full netmask syntax
             {
-                if (LookupHost(strNetmask.c_str(), vIP, 1, false)) // Never allow lookup for netmask
-                {
-                    // Copy only the *last* four bytes in case of IPv4, the rest of the mask should stay 1's as
-                    // we don't want pchIPv4 to be part of the mask.
-                    for(int x=astartofs; x<16; ++x)
-                        netmask[x] = vIP[0].ip[x];
-                }
-                else
-                {
-                    valid = false;
+                // Never allow lookup for netmask
+                if (LookupHost(strNetmask.c_str(), vIP, 1, false)) {
+                    ret = CSubNet(network, vIP[0]);
+                    return ret.IsValid();
                 }
             }
         }
+        else
+        {
+            ret = CSubNet(network);
+            return ret.IsValid();
+        }
     }
-    else
-    {
-        valid = false;
-    }
-
-    // Normalize network according to netmask
-    for(int x=0; x<16; ++x)
-        network.ip[x] &= netmask[x];
+    return false;
 }
 
 CSubNet::CSubNet(const CNetAddr &addr):