Safari and getaddrinfo interposing

我写了一个小型动态库，用于插入对getaddrinfo和connect的调用。 我使用 Firefox 和 Safari 上的DYLD_INSERT_LIBRARIES插入此库来劫持 www.apple.com 请求并将它们发送到 www.microsoft.com。 该代码在 Firefox 上有效，但是当 Safari 调用我的插入函数时，它会忽略重定向。

我想知道是否有人深入了解为什么 Safari 忽略重定向，以及是否有办法，也许通过 addrinfo 标志，让 Safari 像 Firefox 一样运行。 我的代码清单如下。

// -*- mode: c++ -*-
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <dlfcn.h>
#include <dns_sd.h>
#include <cstdio>
#include <cstdlib>
#include <cstdarg>
#include <cstring>
#include <string>
typedef int (*connect_type) (int, struct sockaddr const*, socklen_t);
typedef int (*getaddrinfo_type)(
        const char*, const char*, struct addrinfo const*, addrinfo**);
connect_type     real_connect     = 0;
getaddrinfo_type real_getaddrinfo = 0;
int
do_getaddrinfo_impl(const char* nodename, const char* servname,
                    struct addrinfo const* hints, struct addrinfo** ppai) 
{
    int result = real_getaddrinfo (nodename, servname, hints, ppai);
    if(result != 0) {
        fprintf(stderr, "! real_getaddrinfo error on %s: %sn", nodename, gai_strerror(result));
    }
    return result;
}
int
do_getaddrinfo(const char* nodename, const char* servname,
               struct addrinfo const* hints, struct addrinfo** ppai) 
{
    if (0 == nodename) {
        return do_getaddrinfo_impl(nodename, servname, hints, ppai);
    }
    if (hints->ai_family == AF_INET6) {
        printf ("# do_getaddrinfo : IPv6 resolutionn");
        return do_getaddrinfo_impl(nodename, servname, hints, ppai);
    }
    if (   hints->ai_flags & AI_PASSIVE 
        || hints->ai_flags & AI_CANONNAME 
        || hints->ai_flags & AI_NUMERICHOST 
        || hints->ai_flags & AI_NUMERICSERV) {
        printf ("# do_getaddrinfo : unsupported resolution flagsn");
        return do_getaddrinfo_impl (nodename, servname, hints, ppai);
    }
    if ((hints->ai_flags & AI_V4MAPPED) && !(hints->ai_flags & AI_ALL)) {
        printf ("# do_getaddrinfo : unsupported IPv6-mappingn");
        return do_getaddrinfo_impl (nodename, servname, hints, ppai);
    }
    // redirect requests for www.apple.com to microsoft at 65.55.57.80 (0x41373950)
    if(0 == strcmp(nodename, "www.apple.com")) {
        addrinfo* pai = (addrinfo*)calloc (1, sizeof (addrinfo));
        pai->ai_flags    = hints->ai_flags;
        pai->ai_family   = AF_INET;
        pai->ai_socktype = hints->ai_socktype;
        pai->ai_protocol = IPPROTO_TCP;
        pai->ai_addrlen  = sizeof (sockaddr_in);
        sockaddr* psa = reinterpret_cast< sockaddr* > (
            calloc (1, sizeof (sockaddr)));
        sockaddr_in& sain = reinterpret_cast< sockaddr_in& > (*psa);
#if !defined (POS_NO_SIN_LEN)
        sain.sin_len = sizeof *psa;
#endif // POS_NO_SIN_LEN
        sain.sin_family = AF_INET;
        sain.sin_addr.s_addr = htonl(0x41373950);
        pai->ai_addr = psa;
        pai->ai_canonname = 0;
        pai->ai_next = 0;
        *ppai = pai;
        return 0;
    }
    else {
        return do_getaddrinfo_impl(nodename, servname, hints, ppai);
    }
}
////////////////////////////////////////////////////////////////////////
extern "C" {
int
fake_getaddrinfo(const char* nodename, const char* servname,
                 struct addrinfo const* hints, struct addrinfo** ppai)
{
    if (real_getaddrinfo == 0)
        real_getaddrinfo = &getaddrinfo;
    return do_getaddrinfo (nodename, servname, hints, ppai);
}
int
fake_connect (int s, sockaddr const* ptr, socklen_t len)
{
    if (real_connect == 0)
        real_connect = &connect;
    return do_connect (s, ptr, len);
}
__attribute__((used)) static struct {
    void const *a, *b; 
} arr [] __attribute__ ((section ("__DATA, __interpose"))) = {
    { (void*)fake_connect, (void*)connect },
    { (void*)fake_getaddrinfo, (void*)getaddrinfo }
};
} // extern "C"