looper/subprojects/mpg123/src/resolver.c
2024-09-28 10:31:18 -07:00

340 lines
8.4 KiB
C

/*
resolver.c: TCP network stuff, for IPv4 and IPv6
Oh, and also some URL parsing... extracting host name and such.
copyright 2008-2023 by the mpg123 project - free software under the terms of the LGPL 2.1
see COPYING and AUTHORS files in distribution or http://mpg123.org
initially written Thomas Orgis (based on httpget.c)
The idea is to have everything involving the game between URLs and IPs/connections separated here.
I begin with the outsourcing of IPv4 stuff, then make the stuff generic.
*/
/* Newer glibc is strict about this: getaddrinfo() stuff needs POSIX2K. */
#define _POSIX_C_SOURCE 200112L
#include "mpg123app.h"
#ifdef NETWORK
#include "common/true.h"
#include "resolver.h"
#if !defined (WANT_WIN32_SOCKETS)
#include <netdb.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>
#if defined (IPV6) && defined (__OS2__)
#include <libcx/net.h>
#endif
#endif
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#include <unistd.h>
#include "common/debug.h"
int split_url(mpg123_string *url, mpg123_string *auth, mpg123_string *host, mpg123_string *port, mpg123_string *path)
{
size_t pos = 0; /* current position in input URL */
size_t pos2 = 0; /* another position in input URL */
#ifdef IPV6
size_t pos3 = 0; /* yet another (for IPv6 port) */
#endif
char *part = NULL; /* a part of url we work on */
int ret = TRUE; /* return code */
/* Zeroing the output strings; not freeing to avoid unnecessary mallocs. */
if(auth) auth->fill = 0;
if(host) host->fill = 0;
if(port) port->fill = 0;
if(path) path->fill = 0;
if(!url || !url->fill || url->p[url->fill-1] != 0)
{
error("URL string is not good! (Programmer's fault!?)");
return FALSE;
}
if (!(strncmp(url->p+pos, "http://", 7)))
pos += 7; /* Drop protocol. */
/* Extract user[:passwd]@... */
if( (part = strchr(url->p+pos,'@')) )
{
size_t i;
size_t partlen = part - url->p - pos;
int have_auth = TRUE;
/* User names or passwords don't have "/" in them (?), the "@" wasn't for real if we find such. */
for(i=0;i<partlen;i++)
{
if(url->p[pos+i] == '/' )
{
have_auth = FALSE;
break;
}
}
if(have_auth)
{
if(auth != NULL && !mpg123_set_substring(auth, url->p, pos, partlen))
{
error("Cannot set auth string (out of mem?).");
return FALSE;
}
pos += partlen+1; /* Continuing after the "@". */
}
}
/* Extract host name or IP. */
#ifdef IPV6
if(url->p[pos] == '[')
{ /* It's possibly an IPv6 url in [ ] */
++pos;
if( (part = strchr(url->p+pos,']')) != NULL)
{
pos2 = part-url->p;
pos3 = pos2+1; /* : after ] */
}
else { error("Malformed IPv6 URL!"); return FALSE; }
}
else
{
#endif
for(pos2=pos; pos2 < url->fill-1; ++pos2)
{
char a = url->p[pos2];
if( a == ':' || a == '/') break;
}
#ifdef IPV6
pos3 = pos2;
}
#endif
/* At pos2 there is now either a delimiter or the end. */
debug4("hostname between %lu and %lu, %lu chars of %s", (unsigned long)pos, (unsigned long)pos2, (unsigned long)(pos2-pos), url->p + pos);
if(host != NULL && !mpg123_set_substring(host, url->p, pos, pos2-pos))
{
error("Cannot set host string (out of mem?).");
return FALSE;
}
#ifdef IPV6
pos = pos3; /* Look after ], if present. */
#else
pos = pos2;
#endif
/* Now for the port... */
if(url->p[pos] == ':')
{
pos += 1; /* We begin _after_ the ":". */
for(pos2=pos; pos2 < url->fill-1; ++pos2)
if( url->p[pos2] == '/' ) break;
/* Check for port being numbers? Not sure if that's needed. */
if(port) ret = mpg123_set_substring(port, url->p, pos, pos2-pos);
pos = pos2;
}
else if(port) ret = mpg123_set_string(port, "80");
if(!ret)
{
error("Cannot set port string (out of mem?).");
return FALSE;
}
/* Now only the path is left.
If there is no path at all, assume "/" */
if(path) ret = url->p[pos] == 0
? mpg123_set_string(path, "/")
: mpg123_set_substring(path, url->p, pos, url->fill-1-pos);
if(!ret) error("Cannot set path string (out of mem?)");
return ret;
}
/* Switch between blocking and non-blocking mode. */
#if !defined (WANT_WIN32_SOCKETS)
static void nonblock(int sock)
{
int flags = fcntl(sock, F_GETFL);
flags |= O_NONBLOCK;
fcntl(sock, F_SETFL, flags);
}
static void block(int sock)
{
int flags = fcntl(sock, F_GETFL);
flags &= ~O_NONBLOCK;
fcntl(sock, F_SETFL, flags);
}
/* If we want a timeout, connect non-blocking and wait for that long... */
static int timeout_connect(int sockfd, const struct sockaddr *serv_addr, socklen_t addrlen)
{
if(param.timeout > 0)
{
int err;
nonblock(sockfd);
err = connect(sockfd, serv_addr, addrlen);
if(err == 0)
{
debug("immediately successful");
block(sockfd);
return 0;
}
else if(errno == EINPROGRESS)
{
struct timeval tv;
fd_set fds;
tv.tv_sec = param.timeout;
tv.tv_usec = 0;
debug("in progress, waiting...");
FD_ZERO(&fds);
FD_SET(sockfd, &fds);
err = select(sockfd+1, NULL, &fds, NULL, &tv);
if(err > 0)
{
socklen_t len = sizeof(err);
if( (getsockopt(sockfd, SOL_SOCKET, SO_ERROR, &err, &len) == 0)
&& (err == 0) )
{
debug("non-blocking connect has been successful");
block(sockfd);
return 0;
}
else
{
error1("connection error: %s", strerror(err));
return -1;
}
}
else if(err == 0)
{
error("connection timed out");
return -1;
}
else
{
error1("error from select(): %s", INT123_strerror(errno));
return -1;
}
}
else
{
error1("connection failed: %s", INT123_strerror(errno));
return err;
}
}
else
{
if(connect(sockfd, serv_addr, addrlen))
{
error1("connection failed: %s", INT123_strerror(errno));
return -1;
}
else return 0; /* _good_ */
}
}
/* So, this then is the only routine that should know about IPv4 or v6 in future. */
int open_connection(mpg123_string *host, mpg123_string *port)
{
#ifndef IPV6 /* The legacy code for IPv4. No real change to keep all compatibility. */
#ifndef INADDR_NONE
#define INADDR_NONE 0xffffffff
#endif
struct sockaddr_in server;
struct hostent *myhostent;
struct in_addr myaddr;
int isip = 1;
char *cptr = host->p;
int sock = -1;
if(param.verbose>1) fprintf(stderr, "Note: Attempting old-style connection to %s\n", host->p);
/* Resolve to IP; parse port number. */
while(*cptr) /* Iterate over characters of hostname, check if it's an IP or name. */
{
if ((*cptr < '0' || *cptr > '9') && *cptr != '.')
{
isip = 0;
break;
}
cptr++;
}
if(!isip)
{ /* Name lookup. */
if (!(myhostent = gethostbyname(host->p))) return -1;
memcpy (&myaddr, myhostent->h_addr_list[0], sizeof(myaddr));
server.sin_addr.s_addr = myaddr.s_addr;
}
else /* Just use the IP. */
if((server.sin_addr.s_addr = inet_addr(host->p)) == INADDR_NONE)
return -1;
server.sin_port = htons(atoi(port->p));
server.sin_family = AF_INET;
if((sock = socket(PF_INET, SOCK_STREAM, 6)) < 0)
{
error1("Cannot create socket: %s", INT123_strerror(errno));
return -1;
}
if(timeout_connect(sock, (struct sockaddr *)&server, sizeof(server)))
return -1;
#else /* Host lookup and connection in a protocol independent manner. */
struct addrinfo hints;
struct addrinfo *addr, *addrlist;
int ret, sock = -1;
if(param.verbose>1) fprintf(stderr, "Note: Attempting new-style connection to %s\n", host->p);
memset(&hints, 0, sizeof(struct addrinfo));
hints.ai_family = AF_UNSPEC; /* We accept both IPv4 and IPv6 ... and perhaps IPv8;-) */
hints.ai_socktype = SOCK_STREAM;
hints.ai_flags = 0;
#ifdef HAVE_GAI_ADDRCONFIG
hints.ai_flags |= AI_ADDRCONFIG; /* Only ask for addresses that we have configured interfaces for. */
#endif
ret = getaddrinfo(host->p, port->p, &hints, &addrlist);
if(ret != 0)
{
error3("Resolving %s:%s: %s", host->p, port->p, gai_strerror(ret));
return -1;
}
addr = addrlist;
while(addr != NULL)
{
sock = socket(addr->ai_family, addr->ai_socktype, addr->ai_protocol);
if(sock >= 0)
{
if(timeout_connect(sock, addr->ai_addr, addr->ai_addrlen) == 0)
break;
close(sock);
sock=-1;
}
addr=addr->ai_next;
}
if(sock < 0) error2("Cannot resolve/connect to %s:%s!", host->p, port->p);
freeaddrinfo(addrlist);
#endif
return sock; /* Hopefully, that's an open socket to talk with. */
}
#endif /* !defined (WANT_WIN32_SOCKETS) */
#else /* NETWORK */
void resolver_dummy_without_sense()
{
/* Some compilers don't like empty source files. */
}
#endif