Add meshlink_set_canonical_address().

This introduces the concept of a canonical address for a node, which is
its "official" address/port. It is only set manually, and never updated
or removed when other addresses have been discovered for this node.

Also, this changed meshlink_add_address(mesh, address) to be equivalent to
meshlink_set_canonical_address(mesh, meshlink_get_self(mesh), address, NULL).
While not strictly equivalent to the old behaviour, it matches the
documented intent of this function.

diff --git a/src/meshlink++.h b/src/meshlink++.h
index 83eafdfa15c26e852b5417445388953c779889f2..4cea8cfa206334e07b9b106b7941ce15daeeb4da 100644 (file)
--- a/src/meshlink++.h
+++ b/src/meshlink++.h
@@ -360,6 +360,42 @@ public:
                return meshlink_verify(handle, source, data, len, signature, siglen);
        }
 
+       /// Set the canonical Address for a node.
+       /** This function sets the canonical Address for a node.
+        *  This address is stored permanently until it is changed by another call to this function,
+        *  unlike other addresses associated with a node,
+        *  such as those added with meshlink_hint_address() or addresses discovered at runtime.
+        *
+        *  If a canonical Address is set for the local node,
+        *  it will be used for the hostname part of generated invitation URLs.
+        *
+        *  @param node         A pointer to a meshlink_node_t describing the node.
+        *  @param address      A nul-terminated C string containing the address, which can be either in numeric format or a hostname.
+        *  @param port         A nul-terminated C string containing the port, which can be either in numeric or symbolic format.
+        *                      If it is NULL, the listening port's number will be used.
+        *
+        *  @return             This function returns true if the address was added, false otherwise.
+        */
+       bool set_canonical_address(node *node, const char *address, const char *port = NULL) {
+               return meshlink_set_canonical_address(handle, node, address, port);
+       }
+
+       /// Set the canonical Address for the local node.
+       /** This function sets the canonical Address for the local node.
+        *  This address is stored permanently until it is changed by another call to this function,
+        *  unlike other addresses associated with a node,
+        *  such as those added with meshlink_hint_address() or addresses discovered at runtime.
+        *
+        *  @param address      A nul-terminated C string containing the address, which can be either in numeric format or a hostname.
+        *  @param port         A nul-terminated C string containing the port, which can be either in numeric or symbolic format.
+        *                      If it is NULL, the listening port's number will be used.
+        *
+        *  @return             This function returns true if the address was added, false otherwise.
+        */
+       bool set_canonical_address(const char *address, const char *port = NULL) {
+               return meshlink_set_canonical_address(handle, get_self(), address, port);
+       }
+
        /// Add an Address for the local node.
        /** This function adds an Address for the local node, which will be used for invitation URLs.
         *

diff --git a/src/meshlink.c b/src/meshlink.c
index 1de54e916dab53abaa5f85a3db8739783fa3d3f1..f6121a1ea67f589335f271a7b3edd39568ca8435 100644 (file)
--- a/src/meshlink.c
+++ b/src/meshlink.c
@@ -59,6 +59,7 @@ const var_t variables[] = {
        {"ConnectTo", VAR_SERVER | VAR_MULTIPLE | VAR_SAFE},
        {"Name", VAR_SERVER},
        /* Host configuration */
+       {"CanonicalAddress", VAR_HOST},
        {"Address", VAR_HOST | VAR_MULTIPLE},
        {"ECDSAPublicKey", VAR_HOST},
        {"Port", VAR_HOST},
@@ -96,6 +97,7 @@ static int rstrip(char *value) {
 
 static void scan_for_hostname(const char *filename, char **hostname, char **port) {
        char line[4096];
+       bool canonical = false;
 
        if(!filename || (*hostname && *port)) {
                return;
@@ -135,25 +137,33 @@ static void scan_for_hostname(const char *filename, char **hostname, char **port
 
                p += strspn(p, "\t ");
                p[strcspn(p, "\t ")] = 0;
-               // p is now pointing to the port
-
-               // Check that the hostname is a symbolic name (it's not a numeric IPv4 or IPv6 address)
-               if(!q[strspn(q, "0123456789.")] || strchr(q, ':')) {
-                       continue;
-               }
+               // p is now pointing to the port, if present
 
                if(!*port && !strcasecmp(line, "Port")) {
                        *port = xstrdup(q);
-               } else if(!*hostname && !strcasecmp(line, "Address")) {
+               } else if(!canonical && !*hostname && !strcasecmp(line, "Address")) {
+                       // Check that the hostname is a symbolic name (it's not a numeric IPv4 or IPv6 address)
+                       if(!q[strspn(q, "0123456789.")] || strchr(q, ':')) {
+                               continue;
+                       }
+
                        *hostname = xstrdup(q);
 
+                       if(*p) {
+                               free(*port);
+                               *port = xstrdup(p);
+                       }
+               } else if(!strcasecmp(line, "CanonicalAddress")) {
+                       *hostname = xstrdup(q);
+                       canonical = true;
+
                        if(*p) {
                                free(*port);
                                *port = xstrdup(p);
                        }
                }
 
-               if(*hostname && *port) {
+               if(canonical && *hostname && *port) {
                        break;
                }
        }
@@ -162,6 +172,10 @@ static void scan_for_hostname(const char *filename, char **hostname, char **port
 }
 
 static bool is_valid_hostname(const char *hostname) {
+       if(!*hostname) {
+               return false;
+       }
+
        for(const char *p = hostname; *p; p++) {
                if(!(isalnum(*p) || *p == '-' || *p == '.' || *p == ':')) {
                        return false;
@@ -171,6 +185,26 @@ static bool is_valid_hostname(const char *hostname) {
        return true;
 }
 
+static bool is_valid_port(const char *port) {
+       if(!*port) {
+               return false;
+       }
+
+       if(isdigit(*port)) {
+               char *end;
+               unsigned long int result = strtoul(port, &end, 10);
+               return result && result < 65536 && !*end;
+       }
+
+       for(const char *p = port; *p; p++) {
+               if(!(isalnum(*p) || *p == '-')) {
+                       return false;
+               }
+       }
+
+       return true;
+}
+
 static void set_timeout(int sock, int timeout) {
 #ifdef _WIN32
        DWORD tv = timeout;
@@ -1675,8 +1709,8 @@ static bool refresh_invitation_key(meshlink_handle_t *mesh) {
        return mesh->invitation_key;
 }
 
-bool meshlink_add_address(meshlink_handle_t *mesh, const char *address) {
-       if(!mesh || !address) {
+bool meshlink_set_canonical_address(meshlink_handle_t *mesh, meshlink_node_t *node, const char *address, const char *port) {
+       if(!mesh || !node || !address) {
                meshlink_errno = MESHLINK_EINVAL;
                return false;
        }
@@ -1687,15 +1721,32 @@ bool meshlink_add_address(meshlink_handle_t *mesh, const char *address) {
                return false;
        }
 
-       bool rval = false;
+       if(port && !is_valid_port(port)) {
+               logger(mesh, MESHLINK_DEBUG, "Invalid character in port: %s\n", address);
+               meshlink_errno = MESHLINK_EINVAL;
+               return false;
+       }
+
+       char *canonical_address;
+
+       if(port) {
+               xasprintf(&canonical_address, "%s %s", address, port);
+       } else {
+               canonical_address = xstrdup(address);
+       }
 
        pthread_mutex_lock(&(mesh->mesh_mutex));
-       rval = append_config_file(mesh, mesh->self->name, "Address", address);
+       bool rval = modify_config_file(mesh, node->name, "CanonicalAddress", canonical_address, 1);
        pthread_mutex_unlock(&(mesh->mesh_mutex));
 
+       free(canonical_address);
        return rval;
 }
 
+bool meshlink_add_address(meshlink_handle_t *mesh, const char *address) {
+       return meshlink_set_canonical_address(mesh, mesh->self, address, NULL);
+}
+
 bool meshlink_add_external_address(meshlink_handle_t *mesh) {
        if(!mesh) {
                meshlink_errno = MESHLINK_EINVAL;

diff --git a/src/meshlink.h b/src/meshlink.h
index c8b9870df9cb8c1c2b52492d1fbac968f359c539..26d0dfceda73af09b62bbb93565a928192823673 100644 (file)
--- a/src/meshlink.h
+++ b/src/meshlink.h
@@ -403,6 +403,25 @@ extern bool meshlink_sign(meshlink_handle_t *mesh, const void *data, size_t len,
  */
 extern bool meshlink_verify(meshlink_handle_t *mesh, meshlink_node_t *source, const void *data, size_t len, const void *signature, size_t siglen);
 
+/// Set the canonical Address for a node.
+/** This function sets the canonical Address for a node.
+ *  This address is stored permanently until it is changed by another call to this function,
+ *  unlike other addresses associated with a node,
+ *  such as those added with meshlink_hint_address() or addresses discovered at runtime.
+ *
+ *  If a canonical Address is set for the local node,
+ *  it will be used for the hostname part of generated invitation URLs.
+ *
+ *  @param mesh         A handle which represents an instance of MeshLink.
+ *  @param node         A pointer to a meshlink_node_t describing the node.
+ *  @param address      A nul-terminated C string containing the address, which can be either in numeric format or a hostname.
+ *  @param port         A nul-terminated C string containing the port, which can be either in numeric or symbolic format.
+ *                      If it is NULL, the listening port's number will be used.
+ *
+ *  @return             This function returns true if the address was added, false otherwise.
+ */
+extern bool meshlink_set_canonical_address(meshlink_handle_t *mesh, meshlink_node_t *node, const char *address, const char *port);
+
 /// Add an Address for the local node.
 /** This function adds an Address for the local node, which will be used for invitation URLs.
  *

diff --git a/src/net.h b/src/net.h
index 0ff313d0bdafd1d7f120082e46413629aad62ab0..04bd55a50a0a5ff42fc50d2f314738f32d6b58a6 100644 (file)
--- a/src/net.h
+++ b/src/net.h
@@ -60,12 +60,19 @@ typedef enum packet_type_t {
 
 typedef struct outgoing_t {
        char *name;
-       int timeout;
        struct splay_tree_t *config_tree;
+       int timeout;
+       enum {
+               OUTGOING_START,
+               OUTGOING_CANONICAL,
+               OUTGOING_RECENT,
+               OUTGOING_KNOWN,
+               OUTGOING_END,
+               OUTGOING_NO_KNOWN_ADDRESSES,
+       } state;
        struct config_t *cfg;
-       struct addrinfo *ai; // addresses from config files
+       struct addrinfo *ai;
        struct addrinfo *aip;
-       struct addrinfo *nai; // addresses known via other online nodes (use free_known_addresses())
        timeout_t ev;
        struct meshlink_handle *mesh;
 } outgoing_t;

diff --git a/src/net_socket.c b/src/net_socket.c
index 68bf98f4e57ea5570c553bdef87b7c5869c5a46c..01ef942983d610636866f0ffc9ad030114788f56 100644 (file)
--- a/src/net_socket.c
+++ b/src/net_socket.c
@@ -389,65 +389,139 @@ static void free_known_addresses(struct addrinfo *ai) {
        }
 }
 
-bool do_outgoing_connection(meshlink_handle_t *mesh, outgoing_t *outgoing) {
-       char *address, *port, *space;
-       struct addrinfo *proxyai = NULL;
-       int result;
+static bool get_recent(meshlink_handle_t *mesh, outgoing_t *outgoing) {
+       node_t *n = lookup_node(mesh, outgoing->name);
 
-begin:
+       if(!n) {
+               return false;
+       }
 
-       if(!outgoing->ai && !outgoing->nai) {
-               if(!outgoing->cfg) {
-                       logger(mesh, MESHLINK_ERROR, "Could not set up a meta connection to %s", outgoing->name);
-                       retry_outgoing(mesh, outgoing);
-                       return false;
+       outgoing->ai = get_known_addresses(n);
+       outgoing->aip = outgoing->ai;
+       return outgoing->aip;
+}
+
+static bool get_next_ai(meshlink_handle_t *mesh, outgoing_t *outgoing) {
+       if(!outgoing->ai) {
+               char *address = NULL;
+
+               if(get_config_string(outgoing->cfg, &address)) {
+                       char *port;
+                       char *space = strchr(address, ' ');
+
+                       if(space) {
+                               port = xstrdup(space + 1);
+                               *space = 0;
+                       } else {
+                               if(!get_config_string(lookup_config(outgoing->config_tree, "Port"), &port)) {
+                                       logger(mesh, MESHLINK_ERROR, "No Port known for %s", outgoing->name);
+                                       return false;
+                               }
+                       }
+
+                       outgoing->ai = str2addrinfo(address, port, SOCK_STREAM);
+                       free(port);
+                       free(address);
                }
 
-               get_config_string(outgoing->cfg, &address);
+               outgoing->aip = outgoing->ai;
+       } else {
+               outgoing->aip = outgoing->aip->ai_next;
+       }
+
+       return outgoing->aip;
+}
 
-               space = strchr(address, ' ');
+static bool get_next_cfg(meshlink_handle_t *mesh, outgoing_t *outgoing, char *variable) {
+       (void)mesh;
 
-               if(space) {
-                       port = xstrdup(space + 1);
-                       *space = 0;
-               } else {
-                       // TODO: Only allow Address statements?
-                       if(!get_config_string(lookup_config(outgoing->config_tree, "Port"), &port)) {
-                               logger(mesh, MESHLINK_ERROR, "No Port known for %s", outgoing->name);
-                               retry_outgoing(mesh, outgoing);
-                               return false;
+       if(!outgoing->cfg) {
+               outgoing->cfg = lookup_config(outgoing->config_tree, variable);
+       } else {
+               outgoing->cfg = lookup_config_next(outgoing->config_tree, outgoing->cfg);
+       }
+
+       return outgoing->cfg;
+}
+
+static bool get_next_outgoing_address(meshlink_handle_t *mesh, outgoing_t *outgoing) {
+       bool start = false;
+
+       if(outgoing->state == OUTGOING_START) {
+               start = true;
+               outgoing->state = OUTGOING_CANONICAL;
+       }
+
+       if(outgoing->state == OUTGOING_CANONICAL) {
+               if(outgoing->aip || get_next_cfg(mesh, outgoing, "CanonicalAddress")) {
+                       if(get_next_ai(mesh, outgoing)) {
+                               return true;
+                       } else {
+                               freeaddrinfo(outgoing->ai);
+                               outgoing->ai = NULL;
+                               outgoing->aip = NULL;
                        }
                }
 
-               outgoing->ai = str2addrinfo(address, port, SOCK_STREAM);
-               free(address);
-               free(port);
-
-               outgoing->aip = outgoing->ai;
-               outgoing->cfg = lookup_config_next(outgoing->config_tree, outgoing->cfg);
+               outgoing->state = OUTGOING_RECENT;
        }
 
-       if(!outgoing->aip) {
-               if(outgoing->ai) {
-                       freeaddrinfo(outgoing->ai);
+       if(outgoing->state == OUTGOING_RECENT) {
+               if(outgoing->aip || get_next_cfg(mesh, outgoing, "Address")) {
+                       if(get_next_ai(mesh, outgoing)) {
+                               return true;
+                       } else {
+                               freeaddrinfo(outgoing->ai);
+                               outgoing->ai = NULL;
+                               outgoing->aip = NULL;
+                       }
                }
 
-               outgoing->ai = NULL;
+               outgoing->state = OUTGOING_KNOWN;
+       }
 
-               if(outgoing->nai) {
-                       free_known_addresses(outgoing->nai);
+       if(outgoing->state == OUTGOING_KNOWN) {
+               if(outgoing->aip || get_recent(mesh, outgoing)) {
+                       if(get_next_ai(mesh, outgoing)) {
+                               return true;
+                       } else {
+                               free_known_addresses(outgoing->ai);
+                               outgoing->ai = NULL;
+                               outgoing->aip = NULL;
+                       }
                }
 
-               outgoing->nai = NULL;
+               outgoing->state = OUTGOING_END;
+       }
 
-               goto begin;
+       if(start) {
+               outgoing->state = OUTGOING_NO_KNOWN_ADDRESSES;
+       }
+
+       return false;
+}
+
+bool do_outgoing_connection(meshlink_handle_t *mesh, outgoing_t *outgoing) {
+       struct addrinfo *proxyai = NULL;
+       int result;
+
+begin:
+
+       if(!get_next_outgoing_address(mesh, outgoing)) {
+               if(outgoing->state == OUTGOING_NO_KNOWN_ADDRESSES) {
+                       logger(mesh, MESHLINK_ERROR, "No known addresses for %s", outgoing->name);
+               } else {
+                       logger(mesh, MESHLINK_ERROR, "Could not set up a meta connection to %s", outgoing->name);
+                       retry_outgoing(mesh, outgoing);
+               }
+
+               return false;
        }
 
        connection_t *c = new_connection();
        c->outgoing = outgoing;
 
        memcpy(&c->address, outgoing->aip->ai_addr, outgoing->aip->ai_addrlen);
-       outgoing->aip = outgoing->aip->ai_next;
 
        char *hostname = sockaddr2hostname(&c->address);
 
@@ -537,28 +611,28 @@ void setup_outgoing_connection(meshlink_handle_t *mesh, outgoing_t *outgoing) {
                return;
        }
 
+
+       if(outgoing->ai) {
+               if(outgoing->state == OUTGOING_KNOWN) {
+                       free_known_addresses(outgoing->ai);
+               } else {
+                       freeaddrinfo(outgoing->ai);
+               }
+       }
+
+       outgoing->cfg = NULL;
+
        exit_configuration(&outgoing->config_tree); // discard old configuration if present
        init_configuration(&outgoing->config_tree);
        read_host_config(mesh, outgoing->config_tree, outgoing->name);
-       outgoing->cfg = lookup_config(outgoing->config_tree, "Address");
-
        get_config_bool(lookup_config(outgoing->config_tree, "blacklisted"), &blacklisted);
 
+       outgoing->state = OUTGOING_START;
+
        if(blacklisted) {
                return;
        }
 
-       if(!outgoing->cfg) {
-               if(n) {
-                       outgoing->aip = outgoing->nai = get_known_addresses(n);
-               }
-
-               if(!outgoing->nai) {
-                       logger(mesh, MESHLINK_ERROR, "No address known for %s", outgoing->name);
-                       return;
-               }
-       }
-
        do_outgoing_connection(mesh, outgoing);
 }
 
@@ -670,11 +744,11 @@ static void free_outgoing(outgoing_t *outgoing) {
        timeout_del(&mesh->loop, &outgoing->ev);
 
        if(outgoing->ai) {
-               freeaddrinfo(outgoing->ai);
-       }
-
-       if(outgoing->nai) {
-               free_known_addresses(outgoing->nai);
+               if(outgoing->state == OUTGOING_KNOWN) {
+                       free_known_addresses(outgoing->ai);
+               } else {
+                       freeaddrinfo(outgoing->ai);
+               }
        }
 
        if(outgoing->config_tree) {

diff --git a/test/trio.c b/test/trio.c
index 2cb14bd301af273c37c9948a6efc58cd80be96c8..c82821f1caf9dfb174f49066e79dc6a42f311de5 100644 (file)
--- a/test/trio.c
+++ b/test/trio.c
@@ -59,6 +59,8 @@ int main() {
                mesh[i] = meshlink_open(path, name[i], "trio", DEV_CLASS_BACKBONE);
                assert(mesh[i]);
 
+               meshlink_add_address(mesh[i], "localhost");
+
                data[i] = meshlink_export(mesh[i]);
                assert(data[i]);
        }
@@ -81,7 +83,7 @@ int main() {
        // start the nodes
 
        for(int i = 0; i < 3; i++) {
-               meshlink_start(mesh[i]);
+               assert(meshlink_start(mesh[i]));
        }
 
        // the nodes should now learn about each other
@@ -122,7 +124,7 @@ int main() {
        meshlink_set_log_cb(mesh[1], MESHLINK_DEBUG, log_cb);
 
        for(int i = 1; i < 3; i++) {
-               meshlink_start(mesh[i]);
+               assert(meshlink_start(mesh[i]));
        }
 
        assert(meshlink_get_node(mesh[1], name[2]));