/* * Given an IPv4 or IPv6 dotted string address, this converts it to a proper * allocated Curl_addrinfo struct and returns it. */ Curl_addrinfo *Curl_str2addr(char *address, int port) { struct in_addr in; if(Curl_inet_pton(AF_INET, address, &in) > 0) /* This is a dotted IP address 123.123.123.123-style */ return Curl_ip2addr(AF_INET, &in, address, port); #ifdef ENABLE_IPV6 else { struct in6_addr in6; if(Curl_inet_pton(AF_INET6, address, &in6) > 0) /* This is a dotted IPv6 address ::1-style */ return Curl_ip2addr(AF_INET6, &in6, address, port); } #endif return NULL; /* bad input format */ }
/* * Curl_getaddrinfo() - for Windows threading without ENABLE_IPV6. */ Curl_addrinfo *Curl_getaddrinfo(struct connectdata *conn, const char *hostname, int port, int *waitp) { struct hostent *h = NULL; struct SessionHandle *data = conn->data; in_addr_t in; *waitp = 0; /* don't wait, we act synchronously */ in = inet_addr(hostname); if (in != CURL_INADDR_NONE) /* This is a dotted IP address 123.123.123.123-style */ return Curl_ip2addr(in, hostname, port); /* fire up a new resolver thread! */ if (init_resolve_thread(conn, hostname, port, NULL)) { *waitp = TRUE; /* please wait for the response */ return NULL; } /* fall-back to blocking version */ infof(data, "init_resolve_thread() failed for %s; %s\n", hostname, Curl_strerror(conn, ERRNO)); h = gethostbyname(hostname); if (!h) { infof(data, "gethostbyname(2) failed for %s:%d; %s\n", hostname, port, Curl_strerror(conn, SOCKERRNO)); return NULL; } return Curl_he2ai(h, port); }
/* * Curl_getaddrinfo() - when using ares * * Returns name information about the given hostname and port number. If * successful, the 'hostent' is returned and the forth argument will point to * memory we need to free after use. That memory *MUST* be freed with * Curl_freeaddrinfo(), nothing else. */ Curl_addrinfo *Curl_getaddrinfo(struct connectdata *conn, char *hostname, int port, int *waitp) { char *bufp; struct SessionHandle *data = conn->data; in_addr_t in = inet_addr(hostname); *waitp = FALSE; if (in != CURL_INADDR_NONE) { /* This is a dotted IP address 123.123.123.123-style */ return Curl_ip2addr(in, hostname, port); } bufp = strdup(hostname); if(bufp) { Curl_safefree(conn->async.hostname); conn->async.hostname = bufp; conn->async.port = port; conn->async.done = FALSE; /* not done */ conn->async.status = 0; /* clear */ conn->async.dns = NULL; /* clear */ /* areschannel is already setup in the Curl_open() function */ ares_gethostbyname(data->state.areschannel, hostname, PF_INET, (ares_host_callback)Curl_addrinfo4_callback, conn); *waitp = TRUE; /* please wait for the response */ } return NULL; /* no struct yet */ }
/* * Curl_getaddrinfo() - for platforms without getaddrinfo */ Curl_addrinfo *Curl_resolver_getaddrinfo(struct connectdata *conn, const char *hostname, int port, int *waitp) { struct in_addr in; *waitp = 0; /* default to synchronous response */ if(Curl_inet_pton(AF_INET, hostname, &in) > 0) /* This is a dotted IP address 123.123.123.123-style */ return Curl_ip2addr(AF_INET, &in, hostname, port); /* fire up a new resolver thread! */ if(init_resolve_thread(conn, hostname, port, NULL)) { *waitp = 1; /* expect asynchronous response */ return NULL; } /* fall-back to blocking version */ return Curl_ipv4_resolve_r(hostname, port); }
/* * Curl_resolver_getaddrinfo() - when using ares * * Returns name information about the given hostname and port number. If * successful, the 'hostent' is returned and the forth argument will point to * memory we need to free after use. That memory *MUST* be freed with * Curl_freeaddrinfo(), nothing else. */ Curl_addrinfo *Curl_resolver_getaddrinfo(struct connectdata *conn, const char *hostname, int port, int *waitp) { char *bufp; struct SessionHandle *data = conn->data; struct in_addr in; int family = PF_INET; #ifdef ENABLE_IPV6 /* CURLRES_IPV6 */ struct in6_addr in6; #endif /* CURLRES_IPV6 */ *waitp = 0; /* default to synchronous response */ /* First check if this is an IPv4 address string */ if(Curl_inet_pton(AF_INET, hostname, &in) > 0) { /* This is a dotted IP address 123.123.123.123-style */ return Curl_ip2addr(AF_INET, &in, hostname, port); } #ifdef ENABLE_IPV6 /* CURLRES_IPV6 */ /* Otherwise, check if this is an IPv6 address string */ if(Curl_inet_pton (AF_INET6, hostname, &in6) > 0) /* This must be an IPv6 address literal. */ return Curl_ip2addr(AF_INET6, &in6, hostname, port); switch(conn->ip_version) { default: #if ARES_VERSION >= 0x010601 family = PF_UNSPEC; /* supported by c-ares since 1.6.1, so for older c-ares versions this just falls through and defaults to PF_INET */ break; #endif case CURL_IPRESOLVE_V4: family = PF_INET; break; case CURL_IPRESOLVE_V6: family = PF_INET6; break; } #endif /* CURLRES_IPV6 */ bufp = strdup(hostname); if(bufp) { struct ResolverResults *res = NULL; Curl_safefree(conn->async.hostname); conn->async.hostname = bufp; conn->async.port = port; conn->async.done = FALSE; /* not done */ conn->async.status = 0; /* clear */ conn->async.dns = NULL; /* clear */ res = calloc(sizeof(struct ResolverResults),1); if(!res) { Curl_safefree(conn->async.hostname); conn->async.hostname = NULL; return NULL; } conn->async.os_specific = res; /* initial status - failed */ res->last_status = ARES_ENOTFOUND; #ifdef ENABLE_IPV6 /* CURLRES_IPV6 */ if(family == PF_UNSPEC) { if(Curl_ipv6works()) { res->num_pending = 2; /* areschannel is already setup in the Curl_open() function */ ares_gethostbyname((ares_channel)data->state.resolver, hostname, PF_INET, query_completed_cb, conn); ares_gethostbyname((ares_channel)data->state.resolver, hostname, PF_INET6, query_completed_cb, conn); } else { res->num_pending = 1; /* areschannel is already setup in the Curl_open() function */ ares_gethostbyname((ares_channel)data->state.resolver, hostname, PF_INET, query_completed_cb, conn); } } else #endif /* CURLRES_IPV6 */ { res->num_pending = 1; /* areschannel is already setup in the Curl_open() function */ ares_gethostbyname((ares_channel)data->state.resolver, hostname, family, query_completed_cb, conn); } *waitp = 1; /* expect asynchronous response */ } return NULL; /* no struct yet */ }
/* * Curl_resolver_getaddrinfo() - for getaddrinfo */ Curl_addrinfo *Curl_resolver_getaddrinfo(struct connectdata *conn, const char *hostname, int port, int *waitp) { struct addrinfo hints; struct in_addr in; Curl_addrinfo *res; int error; char sbuf[12]; int pf = PF_INET; #ifdef CURLRES_IPV6 struct in6_addr in6; #endif /* CURLRES_IPV6 */ *waitp = 0; /* default to synchronous response */ #ifndef USE_RESOLVE_ON_IPS /* First check if this is an IPv4 address string */ if(Curl_inet_pton(AF_INET, hostname, &in) > 0) /* This is a dotted IP address 123.123.123.123-style */ return Curl_ip2addr(AF_INET, &in, hostname, port); #ifdef CURLRES_IPV6 /* check if this is an IPv6 address string */ if(Curl_inet_pton(AF_INET6, hostname, &in6) > 0) /* This is an IPv6 address literal */ return Curl_ip2addr(AF_INET6, &in6, hostname, port); #endif /* CURLRES_IPV6 */ #endif /* !USE_RESOLVE_ON_IPS */ #ifdef CURLRES_IPV6 /* * Check if a limited name resolve has been requested. */ switch(conn->ip_version) { case CURL_IPRESOLVE_V4: pf = PF_INET; break; case CURL_IPRESOLVE_V6: pf = PF_INET6; break; default: pf = PF_UNSPEC; break; } if((pf != PF_INET) && !Curl_ipv6works()) /* The stack seems to be a non-IPv6 one */ pf = PF_INET; #endif /* CURLRES_IPV6 */ memset(&hints, 0, sizeof(hints)); hints.ai_family = pf; hints.ai_socktype = conn->socktype; snprintf(sbuf, sizeof(sbuf), "%d", port); /* fire up a new resolver thread! */ if(init_resolve_thread(conn, hostname, port, &hints)) { *waitp = 1; /* expect asynchronous response */ return NULL; } /* fall-back to blocking version */ infof(conn->data, "init_resolve_thread() failed for %s; %s\n", hostname, Curl_strerror(conn, ERRNO)); error = Curl_getaddrinfo_ex(hostname, sbuf, &hints, &res); if(error) { infof(conn->data, "getaddrinfo() failed for %s:%d; %s\n", hostname, port, Curl_strerror(conn, SOCKERRNO)); return NULL; } else { Curl_addrinfo_set_port(res, port); } return res; }
/* * Curl_getaddrinfo() - the ipv4 synchronous version. * * The original code to this function was from the Dancer source code, written * by Bjorn Reese, it has since been patched and modified considerably. * * gethostbyname_r() is the thread-safe version of the gethostbyname() * function. When we build for plain IPv4, we attempt to use this * function. There are _three_ different gethostbyname_r() versions, and we * detect which one this platform supports in the configure script and set up * the HAVE_GETHOSTBYNAME_R_3, HAVE_GETHOSTBYNAME_R_5 or * HAVE_GETHOSTBYNAME_R_6 defines accordingly. Note that HAVE_GETADDRBYNAME * has the corresponding rules. This is primarily on *nix. Note that some unix * flavours have thread-safe versions of the plain gethostbyname() etc. * */ Curl_addrinfo *Curl_getaddrinfo(struct connectdata *conn, const char *hostname, int port, int *waitp) { #if defined(HAVE_GETHOSTBYNAME_R_3) int res; #endif Curl_addrinfo *ai = NULL; struct hostent *h = NULL; struct in_addr in; struct hostent *buf = NULL; #ifdef CURL_DISABLE_VERBOSE_STRINGS (void)conn; #endif *waitp = 0; /* don't wait, we act synchronously */ if(Curl_inet_pton(AF_INET, hostname, &in) > 0) /* This is a dotted IP address 123.123.123.123-style */ return Curl_ip2addr(AF_INET, &in, hostname, port); #if defined(HAVE_GETHOSTBYNAME_R) /* * gethostbyname_r() is the preferred resolve function for many platforms. * Since there are three different versions of it, the following code is * somewhat #ifdef-ridden. */ else { int h_errnop; buf = calloc(1, CURL_HOSTENT_SIZE); if(!buf) return NULL; /* major failure */ /* * The clearing of the buffer is a workaround for a gethostbyname_r bug in * qnx nto and it is also _required_ for some of these functions on some * platforms. */ #ifdef HAVE_GETHOSTBYNAME_R_5 /* Solaris, IRIX and more */ h = gethostbyname_r(hostname, (struct hostent *)buf, (char *)buf + sizeof(struct hostent), CURL_HOSTENT_SIZE - sizeof(struct hostent), &h_errnop); /* If the buffer is too small, it returns NULL and sets errno to * ERANGE. The errno is thread safe if this is compiled with * -D_REENTRANT as then the 'errno' variable is a macro defined to get * used properly for threads. */ if(h) { ; } else #endif /* HAVE_GETHOSTBYNAME_R_5 */ #ifdef HAVE_GETHOSTBYNAME_R_6 /* Linux */ (void)gethostbyname_r(hostname, (struct hostent *)buf, (char *)buf + sizeof(struct hostent), CURL_HOSTENT_SIZE - sizeof(struct hostent), &h, /* DIFFERENCE */ &h_errnop); /* Redhat 8, using glibc 2.2.93 changed the behavior. Now all of a * sudden this function returns EAGAIN if the given buffer size is too * small. Previous versions are known to return ERANGE for the same * problem. * * This wouldn't be such a big problem if older versions wouldn't * sometimes return EAGAIN on a common failure case. Alas, we can't * assume that EAGAIN *or* ERANGE means ERANGE for any given version of * glibc. * * For now, we do that and thus we may call the function repeatedly and * fail for older glibc versions that return EAGAIN, until we run out of * buffer size (step_size grows beyond CURL_HOSTENT_SIZE). * * If anyone has a better fix, please tell us! * * ------------------------------------------------------------------- * * On October 23rd 2003, Dan C dug up more details on the mysteries of * gethostbyname_r() in glibc: * * In glibc 2.2.5 the interface is different (this has also been * discovered in glibc 2.1.1-6 as shipped by Redhat 6). What I can't * explain, is that tests performed on glibc 2.2.4-34 and 2.2.4-32 * (shipped/upgraded by Redhat 7.2) don't show this behavior! * * In this "buggy" version, the return code is -1 on error and 'errno' * is set to the ERANGE or EAGAIN code. Note that 'errno' is not a * thread-safe variable. */ if(!h) /* failure */ #endif/* HAVE_GETHOSTBYNAME_R_6 */ #ifdef HAVE_GETHOSTBYNAME_R_3 /* AIX, Digital Unix/Tru64, HPUX 10, more? */ /* For AIX 4.3 or later, we don't use gethostbyname_r() at all, because of * the plain fact that it does not return unique full buffers on each * call, but instead several of the pointers in the hostent structs will * point to the same actual data! This have the unfortunate down-side that * our caching system breaks down horribly. Luckily for us though, AIX 4.3 * and more recent versions have a "completely thread-safe"[*] libc where * all the data is stored in thread-specific memory areas making calls to * the plain old gethostbyname() work fine even for multi-threaded * programs. * * This AIX 4.3 or later detection is all made in the configure script. * * Troels Walsted Hansen helped us work this out on March 3rd, 2003. * * [*] = much later we've found out that it isn't at all "completely * thread-safe", but at least the gethostbyname() function is. */ if(CURL_HOSTENT_SIZE >= (sizeof(struct hostent)+sizeof(struct hostent_data))) { /* August 22nd, 2000: Albert Chin-A-Young brought an updated version * that should work! September 20: Richard Prescott worked on the buffer * size dilemma. */ res = gethostbyname_r(hostname, (struct hostent *)buf, (struct hostent_data *)((char *)buf + sizeof(struct hostent))); h_errnop = SOCKERRNO; /* we don't deal with this, but set it anyway */ } else res = -1; /* failure, too smallish buffer size */ if(!res) { /* success */ h = buf; /* result expected in h */ /* This is the worst kind of the different gethostbyname_r() interfaces. * Since we don't know how big buffer this particular lookup required, * we can't realloc down the huge alloc without doing closer analysis of * the returned data. Thus, we always use CURL_HOSTENT_SIZE for every * name lookup. Fixing this would require an extra malloc() and then * calling Curl_addrinfo_copy() that subsequent realloc()s down the new * memory area to the actually used amount. */ } else #endif /* HAVE_GETHOSTBYNAME_R_3 */ { infof(conn->data, "gethostbyname_r(2) failed for %s\n", hostname); h = NULL; /* set return code to NULL */ free(buf); } #else /* HAVE_GETHOSTBYNAME_R */ /* * Here is code for platforms that don't have gethostbyname_r() or for * which the gethostbyname() is the preferred() function. */ else { #if (defined(NETWARE) && !defined(__NOVELL_LIBC__)) h = gethostbyname((char*)hostname); #else h = gethostbyname(hostname); #endif if(!h) infof(conn->data, "gethostbyname(2) failed for %s\n", hostname); #endif /*HAVE_GETHOSTBYNAME_R */ } if(h) { ai = Curl_he2ai(h, port); if(buf) /* used a *_r() function */ free(buf); } return ai; }
/* * Curl_getaddrinfo() - when using ares * * Returns name information about the given hostname and port number. If * successful, the 'hostent' is returned and the forth argument will point to * memory we need to free after use. That memory *MUST* be freed with * Curl_freeaddrinfo(), nothing else. */ Curl_addrinfo *Curl_getaddrinfo(struct connectdata *conn, const char *hostname, int port, int *waitp) { char *bufp; struct SessionHandle *data = conn->data; struct in_addr in; int family = PF_INET; #ifdef ENABLE_IPV6 /* CURLRES_IPV6 */ struct in6_addr in6; #endif /* CURLRES_IPV6 */ *waitp = FALSE; /* First check if this is an IPv4 address string */ if(Curl_inet_pton(AF_INET, hostname, &in) > 0) { /* This is a dotted IP address 123.123.123.123-style */ return Curl_ip2addr(AF_INET, &in, hostname, port); } #ifdef ENABLE_IPV6 /* CURLRES_IPV6 */ /* Otherwise, check if this is an IPv6 address string */ if (Curl_inet_pton (AF_INET6, hostname, &in6) > 0) { /* This must be an IPv6 address literal. */ return Curl_ip2addr(AF_INET6, &in6, hostname, port); } switch(data->set.ip_version) { default: #if ARES_VERSION >= 0x010601 family = PF_UNSPEC; /* supported by c-ares since 1.6.1, so for older c-ares versions this just falls through and defaults to PF_INET */ break; #endif case CURL_IPRESOLVE_V4: family = PF_INET; break; case CURL_IPRESOLVE_V6: family = PF_INET6; break; } #endif /* CURLRES_IPV6 */ bufp = strdup(hostname); if(bufp) { Curl_safefree(conn->async.hostname); conn->async.hostname = bufp; conn->async.port = port; conn->async.done = FALSE; /* not done */ conn->async.status = 0; /* clear */ conn->async.dns = NULL; /* clear */ /* areschannel is already setup in the Curl_open() function */ ares_gethostbyname(data->state.areschannel, hostname, family, (ares_host_callback)Curl_addrinfo4_callback, conn); *waitp = TRUE; /* please wait for the response */ } return NULL; /* no struct yet */ }