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/**
* @file /magma/network/clients.c
*
* @brief Functions for handling network client connections.
*/
#include "magma.h"
/**
* @brief Get the status of a network client.
* @param client a pointer to the network client object to be queried.
* @return -1 on network errors, 0 for an unknown status, 1 for connected, and 2 for a graceful shutdown.
*/
int_t client_status(client_t *client) {
int_t result = -1;
if (client && client->sockd != -1) {
result = client->status;
}
// If the status is positive, and tls_status returns 0, we use the existing status state.
if (client && client->tls && client->status >= 0 && !tls_status(client->tls)) {
result = client->status;
}
// If the status is positive, and tcp_status returns 0, we use the existing status state.
else if (client && client->sockd != -1 && client->status >= 0 && !tcp_status(client->sockd)) {
result = client->status;
}
// We return -1 if the status is already negative, or connection is otherwise invalid.
else if (client) {
result = client->status = -1;
}
return result;
}
/**
* @brief Establish a TLS connection with a network client instance.
* @param client a pointer to the network client object to have its transport security upgraded.
* @return -1 on failure or 0 on success.
*/
int_t client_secure(client_t *client) {
if (!client) {
return -1;
}
else if (client->tls) {
return 0;
}
else if (!(client->tls = tls_client_alloc(client->sockd))) {
client->status = -1;
return -1;
}
client->status = 1;
return 0;
}
/**
* @brief Establish a network client connection to a remote host.
* @param host a pointer to a null-terminated string containing the hostname of the remote server.
* @param port the port number of the server to which the connection will be established.
* @return NULL on failure or a pointer to a newly initialized network client object for the connection upon success.
*/
client_t * client_connect(chr_t *host, uint32_t port) {
ip_t *ip = NULL;
chr_t service[20];
int_t sd = -1, ret;
client_t *result = NULL;
struct addrinfo hints, *info = NULL, *holder = NULL;
memset(&hints, 0, sizeof(struct addrinfo));
hints.ai_family = AF_UNSPEC; // IPv4 or IPv6
hints.ai_socktype = SOCK_STREAM; // TCP stream socket
hints.ai_flags = AI_NUMERICSERV; // Require a numeric service (aka port) number.
snprintf(service, 20, "%u", port);
// Resolve the hostname.
if ((ret = getaddrinfo(host, service, &hints, &info)) || !info || info->ai_socktype != SOCK_STREAM) {
#ifdef MAGMA_PEDANTIC
if (status()) log_pedantic("Unable to resolve the host %s:%u and create a client connection. { getaddrinfo = %i / errno = %s }", host,
port, ret, strerror_r(errno, MEMORYBUF(256), 256));
#endif
if (info) freeaddrinfo(info);
return NULL ;
}
// We need to loop through all addresses because we may get an multiple IP addresses, and some of
// those addresses may be invalid, or inaccessible. We use a disposable "holder" variable as the iterator,
// so we still call freeaddrinfo on the original info variable, otherwise we will create a memory leak.
holder = info;
while (holder) {
// Create a socket.
if ((sd = socket(holder->ai_family, holder->ai_socktype, holder->ai_protocol)) == -1) {
log_pedantic("Unable to create a socket connection with the host %s:%u. { socket = -1 / errno = %s }",
host, port, strerror_r(errno, MEMORYBUF(1024), 1024));
freeaddrinfo(info);
return NULL;
}
// Attempt a socket connection. If the connection is established, we'll store the IP information in a ip_t structure,
// and set the holder variable to NULL so the loop exits.
if (!(ret = connect(sd, holder->ai_addr, holder->ai_addrlen))) {
if (!(ip = mm_alloc(sizeof(ip_t)))) {
log_pedantic("Unable to store the IP information for the connected host.");
}
else if (holder->ai_addrlen == sizeof(struct sockaddr_in6) && holder->ai_family == AF_INET6) {
mm_copy(&(ip->ip6), &(((struct sockaddr_in6 *)holder->ai_addr)->sin6_addr), sizeof(struct in6_addr));
ip->family = AF_INET6;
}
else if (holder->ai_addrlen == sizeof(struct sockaddr_in) && holder->ai_family == AF_INET) {
mm_copy(&(ip->ip4), &(((struct sockaddr_in *)holder->ai_addr)->sin_addr), sizeof(struct in_addr));
ip->family = AF_INET;
}
else {
log_pedantic("Unrecognized peer address. { family = %i / length = %u }", holder->ai_family, holder->ai_addrlen);
mm_free(ip);
ip = NULL;
}
holder = NULL;
}
// Otherwise, if the connection attempt fails, close the socket descriptor, and if another address record exists, advance
// and try the next candidate.
else {
holder = holder->ai_next;
close(sd);
}
}
// Free the address info.
freeaddrinfo(info);
if (ret) {
log_pedantic("We were unable to connect with the host %s:%u. { connect = %i / errno = %s }",
host, port, ret, strerror_r(errno, MEMORYBUF(1024), 1024));
// close(sd);
return NULL;
}
else if (!(result = mm_alloc(sizeof(client_t))) || !(result->buffer = st_alloc(8192))) {
log_pedantic("Unable to allocate memory for the client connection context.");
mm_cleanup(result, ip);
close(sd);
return NULL;
}
result->ip = ip;
result->sockd = sd;
result->status = 1;
result->port = port;
result->line.length = 0;
result->line.opts = PLACER_T | JOINTED | STACK | FOREIGNDATA;
return result;
}
/**
* @brief Close a network client connection.
* @note If ssl is in use, this will also destroy the overlying ssl session.
* @return This function returns no value.
*/
void client_close(client_t *client) {
if (client) {
if (client->tls) {
tls_free(client->tls);
}
if (client->sockd != -1) {
close(client->sockd);
}
mm_cleanup(client->ip);
st_cleanup(client->buffer);
mm_free(client);
}
return;
}
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