Skip to content

Instantly share code, notes, and snippets.

@anr2me

anr2me/ios_IPAddress.c

Forked from codeswimmer/ios_IPAddress.c
Created January 28, 2022 21:33
Show Gist options
  • Save anr2me/d1dce573117e8af32e862a1bf3de613e to your computer and use it in GitHub Desktop.
Save anr2me/d1dce573117e8af32e862a1bf3de613e to your computer and use it in GitHub Desktop.
Download ZIP

Revisions

  1. @codeswimmer codeswimmer created this gist Jan 15, 2012.
    209 changes: 209 additions & 0 deletions ios_IPAddress.c
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,209 @@
    #include <stdio.h>
    #include <stdlib.h>
    #include <string.h>
    #include <unistd.h>
    #include <sys/ioctl.h>
    #include <sys/types.h>
    #include <sys/socket.h>
    #include <netinet/in.h>
    #include <netdb.h>
    #include <arpa/inet.h>
    #include <sys/sockio.h>
    #include <net/if.h>
    #include <errno.h>
    #include <net/if_dl.h>

    #include "GetAddresses.h"

    #define min(a,b) ((a) < (b) ? (a) : (b))
    #define max(a,b) ((a) > (b) ? (a) : (b))

    #define BUFFERSIZE 4000

    char *if_names[MAXADDRS];
    char *ip_names[MAXADDRS];
    char *hw_addrs[MAXADDRS];
    unsigned long ip_addrs[MAXADDRS];

    static int nextAddr = 0;

    void InitAddresses()
    {
    int i;
    for (i=0; i<MAXADDRS; ++i)
    {
    if_names[i] = ip_names[i] = hw_addrs[i] = NULL;
    ip_addrs[i] = 0;
    }
    }

    void FreeAddresses()
    {
    int i;
    for (i=0; i<MAXADDRS; ++i)
    {
    if (if_names[i] != 0) free(if_names[i]);
    if (ip_names[i] != 0) free(ip_names[i]);
    if (hw_addrs[i] != 0) free(hw_addrs[i]);
    ip_addrs[i] = 0;
    }
    InitAddresses();
    }

    void GetIPAddresses()
    {
    int i, len, flags;
    char buffer[BUFFERSIZE], *ptr, lastname[IFNAMSIZ], *cptr;
    struct ifconf ifc;
    struct ifreq *ifr, ifrcopy;
    struct sockaddr_in *sin;

    char temp[80];

    int sockfd;

    for (i=0; i<MAXADDRS; ++i)
    {
    if_names[i] = ip_names[i] = NULL;
    ip_addrs[i] = 0;
    }

    sockfd = socket(AF_INET, SOCK_DGRAM, 0);
    if (sockfd < 0)
    {
    perror("socket failed");
    return;
    }

    ifc.ifc_len = BUFFERSIZE;
    ifc.ifc_buf = buffer;

    if (ioctl(sockfd, SIOCGIFCONF, &ifc) < 0)
    {
    perror("ioctl error");
    return;
    }

    lastname[0] = 0;

    for (ptr = buffer; ptr < buffer + ifc.ifc_len; )
    {
    ifr = (struct ifreq *)ptr;
    len = max(sizeof(struct sockaddr), ifr->ifr_addr.sa_len);
    ptr += sizeof(ifr->ifr_name) + len; // for next one in buffer

    if (ifr->ifr_addr.sa_family != AF_INET)
    {
    continue; // ignore if not desired address family
    }

    if ((cptr = (char *)strchr(ifr->ifr_name, ':')) != NULL)
    {
    *cptr = 0; // replace colon will null
    }

    if (strncmp(lastname, ifr->ifr_name, IFNAMSIZ) == 0)
    {
    continue; /* already processed this interface */
    }

    memcpy(lastname, ifr->ifr_name, IFNAMSIZ);

    ifrcopy = *ifr;
    ioctl(sockfd, SIOCGIFFLAGS, &ifrcopy);
    flags = ifrcopy.ifr_flags;
    if ((flags & IFF_UP) == 0)
    {
    continue; // ignore if interface not up
    }

    if_names[nextAddr] = (char *)malloc(strlen(ifr->ifr_name)+1);
    if (if_names[nextAddr] == NULL)
    {
    return;
    }
    strcpy(if_names[nextAddr], ifr->ifr_name);

    sin = (struct sockaddr_in *)&ifr->ifr_addr;
    strcpy(temp, inet_ntoa(sin->sin_addr));

    ip_names[nextAddr] = (char *)malloc(strlen(temp)+1);
    if (ip_names[nextAddr] == NULL)
    {
    return;
    }
    strcpy(ip_names[nextAddr], temp);

    ip_addrs[nextAddr] = sin->sin_addr.s_addr;

    ++nextAddr;
    }

    close(sockfd);
    }

    void GetHWAddresses()
    {
    struct ifconf ifc;
    struct ifreq *ifr;
    int i, sockfd;
    char buffer[BUFFERSIZE], *cp, *cplim;
    char temp[80];

    for (i=0; i<MAXADDRS; ++i)
    {
    hw_addrs[i] = NULL;
    }

    sockfd = socket(AF_INET, SOCK_DGRAM, 0);
    if (sockfd < 0)
    {
    perror("socket failed");
    return;
    }

    ifc.ifc_len = BUFFERSIZE;
    ifc.ifc_buf = buffer;

    if (ioctl(sockfd, SIOCGIFCONF, (char *)&ifc) < 0)
    {
    perror("ioctl error");
    close(sockfd);
    return;
    }

    ifr = ifc.ifc_req;

    cplim = buffer + ifc.ifc_len;

    for (cp=buffer; cp < cplim; )
    {
    ifr = (struct ifreq *)cp;
    if (ifr->ifr_addr.sa_family == AF_LINK)
    {
    struct sockaddr_dl *sdl = (struct sockaddr_dl *)&ifr->ifr_addr;
    int a,b,c,d,e,f;
    int i;

    strcpy(temp, (char *)ether_ntoa(LLADDR(sdl)));
    sscanf(temp, "%x:%x:%x:%x:%x:%x", &a, &b, &c, &d, &e, &f);
    sprintf(temp, "%02X:%02X:%02X:%02X:%02X:%02X",a,b,c,d,e,f);

    for (i=0; i<MAXADDRS; ++i)
    {
    if ((if_names[i] != NULL) && (strcmp(ifr->ifr_name, if_names[i]) == 0))
    {
    if (hw_addrs[i] == NULL)
    {
    hw_addrs[i] = (char *)malloc(strlen(temp)+1);
    strcpy(hw_addrs[i], temp);
    break;
    }
    }
    }
    }
    cp += sizeof(ifr->ifr_name) + max(sizeof(ifr->ifr_addr), ifr->ifr_addr.sa_len);
    }

    close(sockfd);
    }
    13 changes: 13 additions & 0 deletions ios_IPAddress.h
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,13 @@
    #define MAXADDRS 32

    extern char *if_names[MAXADDRS];
    extern char *ip_names[MAXADDRS];
    extern char *hw_addrs[MAXADDRS];
    extern unsigned long ip_addrs[MAXADDRS];

    // Function prototypes

    void InitAddresses();
    void FreeAddresses();
    void GetIPAddresses();
    void GetHWAddresses();