sockaddr.c

Apache 2.0.63 is the current stable version of the 2.0 series, and is recommended over any previous

    defined(HAVE_GETHOSTBYADDR_R) && !defined(BEOS)
#ifdef GETHOSTBYNAME_R_HOSTENT_DATA
    struct hostent_data hd;
#else
    char tmp[GETHOSTBYNAME_BUFLEN];
#endif
    int hosterror;
    struct hostent hs, *hptr;

#if defined(GETHOSTBYNAME_R_HOSTENT_DATA)
    /* AIX, HP/UX, D/UX et alia */
    gethostbyaddr_r((char *)&sockaddr->sa.sin.sin_addr, 
                  sizeof(struct in_addr), AF_INET, &hs, &hd);
    hptr = &hs;
#else
#if defined(GETHOSTBYNAME_R_GLIBC2)
    /* Linux glibc2+ */
    gethostbyaddr_r((char *)&sockaddr->sa.sin.sin_addr, 
                    sizeof(struct in_addr), AF_INET,
                    &hs, tmp, GETHOSTBYNAME_BUFLEN - 1, &hptr, &hosterror);
#else
    /* Solaris, Irix et alia */
    hptr = gethostbyaddr_r((char *)&sockaddr->sa.sin.sin_addr, 
                           sizeof(struct in_addr), AF_INET,
                           &hs, tmp, GETHOSTBYNAME_BUFLEN, &hosterror);
#endif /* !defined(GETHOSTBYNAME_R_GLIBC2) */
    if (!hptr) {
        *hostname = NULL;
        return hosterror + APR_OS_START_SYSERR;
    }
#endif /* !defined(GETHOSTBYNAME_R_HOSTENT_DATA) */
#else
    struct hostent *hptr;
    hptr = gethostbyaddr((char *)&sockaddr->sa.sin.sin_addr, 
                         sizeof(struct in_addr), AF_INET);
#endif

    if (hptr) {
        *hostname = sockaddr->hostname = apr_pstrdup(sockaddr->pool, hptr->h_name);
        return APR_SUCCESS;
    }
    *hostname = NULL;
#if defined(WIN32)
    return apr_get_netos_error();
#elif defined(OS2)
    return h_errno;
#else
    return h_errno + APR_OS_START_SYSERR;
#endif
#endif
}

APR_DECLARE(apr_status_t) apr_getservbyname(apr_sockaddr_t *sockaddr,
                                            const char *servname)
{
    struct servent *se;

    if (servname == NULL)
        return APR_EINVAL;

    if ((se = getservbyname(servname, NULL)) != NULL){
        sockaddr->port = htons(se->s_port);
        sockaddr->servname = apr_pstrdup(sockaddr->pool, servname);
        sockaddr->sa.sin.sin_port = se->s_port;
        return APR_SUCCESS;
    }
    return errno;
}

#define V4MAPPED_EQUAL(a,b)                                   \
((a)->sa.sin.sin_family == AF_INET &&                         \
 (b)->sa.sin.sin_family == AF_INET6 &&                        \
 IN6_IS_ADDR_V4MAPPED((struct in6_addr *)(b)->ipaddr_ptr) &&  \
 !memcmp((a)->ipaddr_ptr,                                     \
         &((struct in6_addr *)(b)->ipaddr_ptr)->s6_addr[12],  \
         (a)->ipaddr_len))

APR_DECLARE(int) apr_sockaddr_equal(const apr_sockaddr_t *addr1,
                                    const apr_sockaddr_t *addr2)
{
    if (addr1->ipaddr_len == addr2->ipaddr_len &&
        !memcmp(addr1->ipaddr_ptr, addr2->ipaddr_ptr, addr1->ipaddr_len)) {
        return 1;
    }
#if APR_HAVE_IPV6
    if (V4MAPPED_EQUAL(addr1, addr2)) {
        return 1;
    }
    if (V4MAPPED_EQUAL(addr2, addr1)) {
        return 1;
    }
#endif
    return 0; /* not equal */
}

static apr_status_t parse_network(apr_ipsubnet_t *ipsub, const char *network)
{
    /* legacy syntax for ip addrs: a.b.c. ==> a.b.c.0/24 for example */
    int shift;
    char *s, *t;
    int octet;
    char buf[sizeof "255.255.255.255"];

    if (strlen(network) < sizeof buf) {
        strcpy(buf, network);
    }
    else {
        return APR_EBADIP;
    }

    /* parse components */
    s = buf;
    ipsub->sub[0] = 0;
    ipsub->mask[0] = 0;
    shift = 24;
    while (*s) {
        t = s;
        if (!apr_isdigit(*t)) {
            return APR_EBADIP;
        }
        while (apr_isdigit(*t)) {
            ++t;
        }
        if (*t == '.') {
            *t++ = 0;
        }
        else if (*t) {
            return APR_EBADIP;
        }
        if (shift < 0) {
            return APR_EBADIP;
        }
        octet = atoi(s);
        if (octet < 0 || octet > 255) {
            return APR_EBADIP;
        }
        ipsub->sub[0] |= octet << shift;
        ipsub->mask[0] |= 0xFFUL << shift;
        s = t;
        shift -= 8;
    }
    ipsub->sub[0] = ntohl(ipsub->sub[0]);
    ipsub->mask[0] = ntohl(ipsub->mask[0]);
    ipsub->family = AF_INET;
    return APR_SUCCESS;
}

/* return values:
 * APR_EINVAL     not an IP address; caller should see if it is something else
 * APR_BADIP      IP address portion is is not valid
 * APR_BADMASK    mask portion is not valid
 */

static apr_status_t parse_ip(apr_ipsubnet_t *ipsub, const char *ipstr, int network_allowed)
{
    /* supported flavors of IP:
     *
     * . IPv6 numeric address string (e.g., "fe80::1")
     * 
     *   IMPORTANT: Don't store IPv4-mapped IPv6 address as an IPv6 address.
     *
     * . IPv4 numeric address string (e.g., "127.0.0.1")
     *
     * . IPv4 network string (e.g., "9.67")
     *
     *   IMPORTANT: This network form is only allowed if network_allowed is on.
     */
    int rc;

#if APR_HAVE_IPV6
    rc = apr_inet_pton(AF_INET6, ipstr, ipsub->sub);
    if (rc == 1) {
        if (IN6_IS_ADDR_V4MAPPED((struct in6_addr *)ipsub->sub)) {
            /* apr_ipsubnet_test() assumes that we don't create IPv4-mapped IPv6
             * addresses; this of course forces the user to specify IPv4 addresses
             * in a.b.c.d style instead of ::ffff:a.b.c.d style.
             */
            return APR_EBADIP;
        }
        ipsub->family = AF_INET6;
    }
    else
#endif
    {
        rc = apr_inet_pton(AF_INET, ipstr, ipsub->sub);
        if (rc == 1) {
            ipsub->family = AF_INET;
        }
    }
    if (rc != 1) {
        if (network_allowed) {
            return parse_network(ipsub, ipstr);
        }
        else {
            return APR_EBADIP;
        }
    }
    return APR_SUCCESS;
}

static int looks_like_ip(const char *ipstr)
{
    if (strchr(ipstr, ':')) {
        /* definitely not a hostname; assume it is intended to be an IPv6 address */
        return 1;
    }

    /* simple IPv4 address string check */
    while ((*ipstr == '.') || apr_isdigit(*ipstr))
        ipstr++;
    return (*ipstr == '\0');
}

static void fix_subnet(apr_ipsubnet_t *ipsub)
{
    /* in case caller specified more bits in network address than are
     * valid according to the mask, turn off the extra bits
     */
    int i;

    for (i = 0; i < sizeof ipsub->mask / sizeof(apr_int32_t); i++) {
        ipsub->sub[i] &= ipsub->mask[i];
    }
}

/* be sure not to store any IPv4 address as a v4-mapped IPv6 address */
APR_DECLARE(apr_status_t) apr_ipsubnet_create(apr_ipsubnet_t **ipsub, const char *ipstr, 
                                              const char *mask_or_numbits, apr_pool_t *p)
{
    apr_status_t rv;
    char *endptr;
    long bits, maxbits = 32;

    /* filter out stuff which doesn't look remotely like an IP address; this helps 
     * callers like mod_access which have a syntax allowing hostname or IP address;
     * APR_EINVAL tells the caller that it was probably not intended to be an IP
     * address
     */
    if (!looks_like_ip(ipstr)) {
        return APR_EINVAL;
    }

    *ipsub = apr_pcalloc(p, sizeof(apr_ipsubnet_t));

    /* assume ipstr is an individual IP address, not a subnet */
    memset((*ipsub)->mask, 0xFF, sizeof (*ipsub)->mask);

    rv = parse_ip(*ipsub, ipstr, mask_or_numbits == NULL);
    if (rv != APR_SUCCESS) {
        return rv;
    }

    if (mask_or_numbits) {
#if APR_HAVE_IPV6
        if ((*ipsub)->family == AF_INET6) {
            maxbits = 128;
        }
#endif
        bits = strtol(mask_or_numbits, &endptr, 10);
        if (*endptr == '\0' && bits > 0 && bits <= maxbits) {
            /* valid num-bits string; fill in mask appropriately */
            int cur_entry = 0;
            apr_int32_t cur_bit_value;

            memset((*ipsub)->mask, 0, sizeof (*ipsub)->mask);
            while (bits > 32) {
                (*ipsub)->mask[cur_entry] = 0xFFFFFFFF; /* all 32 bits */
                bits -= 32;
                ++cur_entry;
            }
            cur_bit_value = 0x80000000;
            while (bits) {
                (*ipsub)->mask[cur_entry] |= cur_bit_value;
                --bits;
                cur_bit_value /= 2;
            }
            (*ipsub)->mask[cur_entry] = htonl((*ipsub)->mask[cur_entry]);
        }
        else if (apr_inet_pton(AF_INET, mask_or_numbits, (*ipsub)->mask) == 1 &&
            (*ipsub)->family == AF_INET) {
            /* valid IPv4 netmask */
        }
        else {
            return APR_EBADMASK;
        }
    }

    fix_subnet(*ipsub);

    return APR_SUCCESS;
}

APR_DECLARE(int) apr_ipsubnet_test(apr_ipsubnet_t *ipsub, apr_sockaddr_t *sa)
{
#if APR_HAVE_IPV6
    /* XXX This line will segv on Win32 build with APR_HAVE_IPV6,
     * but without the IPV6 drivers installed.
     */
    if (sa->sa.sin.sin_family == AF_INET) {
        if (ipsub->family == AF_INET &&
            ((sa->sa.sin.sin_addr.s_addr & ipsub->mask[0]) == ipsub->sub[0])) {
            return 1;
        }
    }
    else if (IN6_IS_ADDR_V4MAPPED((struct in6_addr *)sa->ipaddr_ptr)) {
        if (ipsub->family == AF_INET &&
            (((apr_uint32_t *)sa->ipaddr_ptr)[3] & ipsub->mask[0]) == ipsub->sub[0]) {
            return 1;
        }
    }
    else {
        apr_uint32_t *addr = (apr_uint32_t *)sa->ipaddr_ptr;

        if ((addr[0] & ipsub->mask[0]) == ipsub->sub[0] &&
            (addr[1] & ipsub->mask[1]) == ipsub->sub[1] &&
            (addr[2] & ipsub->mask[2]) == ipsub->sub[2] &&
            (addr[3] & ipsub->mask[3]) == ipsub->sub[3]) {
            return 1;
        }
    }
#else
    if ((sa->sa.sin.sin_addr.s_addr & ipsub->mask[0]) == ipsub->sub[0]) {
        return 1;
    }
#endif /* APR_HAVE_IPV6 */
    return 0; /* no match */
}