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Diffstat (limited to 'Utilities/cmcurl/hostip4.c')
| -rw-r--r-- | Utilities/cmcurl/hostip4.c | 456 |
1 files changed, 456 insertions, 0 deletions
diff --git a/Utilities/cmcurl/hostip4.c b/Utilities/cmcurl/hostip4.c new file mode 100644 index 0000000000..1b4c3c1307 --- /dev/null +++ b/Utilities/cmcurl/hostip4.c @@ -0,0 +1,456 @@ +/*************************************************************************** + * _ _ ____ _ + * Project ___| | | | _ \| | + * / __| | | | |_) | | + * | (__| |_| | _ <| |___ + * \___|\___/|_| \_\_____| + * + * Copyright (C) 1998 - 2004, Daniel Stenberg, <daniel@haxx.se>, et al. + * + * This software is licensed as described in the file COPYING, which + * you should have received as part of this distribution. The terms + * are also available at http://curl.haxx.se/docs/copyright.html. + * + * You may opt to use, copy, modify, merge, publish, distribute and/or sell + * copies of the Software, and permit persons to whom the Software is + * furnished to do so, under the terms of the COPYING file. + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY + * KIND, either express or implied. + * + * $Id$ + ***************************************************************************/ + +#include "setup.h" + +#include <string.h> +#include <errno.h> + +#define _REENTRANT + +#if defined(WIN32) && !defined(__GNUC__) || defined(__MINGW32__) +#include <malloc.h> +#else +#ifdef HAVE_SYS_TYPES_H +#include <sys/types.h> +#endif +#ifdef HAVE_SYS_SOCKET_H +#include <sys/socket.h> +#endif +#ifdef HAVE_NETINET_IN_H +#include <netinet/in.h> +#endif +#ifdef HAVE_NETDB_H +#include <netdb.h> +#endif +#ifdef HAVE_ARPA_INET_H +#include <arpa/inet.h> +#endif +#ifdef HAVE_STDLIB_H +#include <stdlib.h> /* required for free() prototypes */ +#endif +#ifdef HAVE_UNISTD_H +#include <unistd.h> /* for the close() proto */ +#endif +#ifdef VMS +#include <in.h> +#include <inet.h> +#include <stdlib.h> +#endif +#endif + +#ifdef HAVE_SETJMP_H +#include <setjmp.h> +#endif + +#ifdef WIN32 +#include <process.h> +#endif + +#if (defined(NETWARE) && defined(__NOVELL_LIBC__)) +#undef in_addr_t +#define in_addr_t unsigned long +#endif + +#include "urldata.h" +#include "sendf.h" +#include "hostip.h" +#include "hash.h" +#include "share.h" +#include "strerror.h" +#include "url.h" + +#define _MPRINTF_REPLACE /* use our functions only */ +#include <curl/mprintf.h> + +#if defined(HAVE_INET_NTOA_R) && !defined(HAVE_INET_NTOA_R_DECL) +#include "inet_ntoa_r.h" +#endif + +#include "curl_memory.h" +/* The last #include file should be: */ +#include "memdebug.h" + +/*********************************************************************** + * Only for plain-ipv4 builds + **********************************************************************/ +#ifdef CURLRES_IPV4 /* plain ipv4 code coming up */ + +/* + * This is a function for freeing name information in a protocol independent + * way. + */ +void Curl_freeaddrinfo(Curl_addrinfo *ai) +{ + Curl_addrinfo *next; + + /* walk over the list and free all entries */ + while(ai) { + next = ai->ai_next; + free(ai); + ai = next; + } +} + +/* + * Curl_ipvalid() checks what CURL_IPRESOLVE_* requirements that might've + * been set and returns TRUE if they are OK. + */ +bool Curl_ipvalid(struct SessionHandle *data) +{ + if(data->set.ip_version == CURL_IPRESOLVE_V6) + /* an ipv6 address was requested and we can't get/use one */ + return FALSE; + + return TRUE; /* OK, proceed */ +} + +struct namebuf { + struct hostent hostentry; + char *h_addr_list[2]; + struct in_addr addrentry; + char h_name[16]; /* 123.123.123.123 = 15 letters is maximum */ +}; + +/* + * Curl_ip2addr() takes a 32bit ipv4 internet address as input parameter + * together with a pointer to the string version of the address, and it + * returns a Curl_addrinfo chain filled in correctly with information for this + * address/host. + * + * The input parameters ARE NOT checked for validity but they are expected + * to have been checked already when this is called. + */ +Curl_addrinfo *Curl_ip2addr(in_addr_t num, char *hostname, int port) +{ + Curl_addrinfo *ai; + struct hostent *h; + struct in_addr *addrentry; + struct namebuf buffer; + struct namebuf *buf = &buffer; + + h = &buf->hostentry; + h->h_addr_list = &buf->h_addr_list[0]; + addrentry = &buf->addrentry; + addrentry->s_addr = num; + h->h_addr_list[0] = (char*)addrentry; + h->h_addr_list[1] = NULL; + h->h_addrtype = AF_INET; + h->h_length = sizeof(*addrentry); + h->h_name = &buf->h_name[0]; + h->h_aliases = NULL; + + /* Now store the dotted version of the address */ + snprintf((char*)(h->h_name), 16, "%s", hostname); + + ai = Curl_he2ai(h, port); + + return ai; +} + +#ifdef CURLRES_SYNCH /* the functions below are for synchronous resolves */ + +/* + * Curl_getaddrinfo() - the ipv4 synchronous version. + * + * The original code to this function was once stolen 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, + char *hostname, + int port, + int *waitp) +{ + Curl_addrinfo *ai = NULL; + struct hostent *h = NULL; + in_addr_t in; + struct SessionHandle *data = conn->data; + struct hostent *buf = NULL; + + (void)port; /* unused in IPv4 code */ + + *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); + } + +#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; + int res=ERANGE; + + buf = (struct hostent *)calloc(CURL_HOSTENT_SIZE, 1); + 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 */ + (void)res; /* prevent compiler warning */ + 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 */ + + res=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= errno; /* 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(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 { + h = gethostbyname(hostname); + if (!h) + infof(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; +} + +#endif /* CURLRES_SYNCH */ + +/* + * Curl_he2ai() translates from a hostent struct to a Curl_addrinfo struct. + * The Curl_addrinfo is meant to work like the addrinfo struct does for IPv6 + * stacks, but for all hosts and environments. + +struct Curl_addrinfo { + int ai_flags; + int ai_family; + int ai_socktype; + int ai_protocol; + size_t ai_addrlen; + struct sockaddr *ai_addr; + char *ai_canonname; + struct addrinfo *ai_next; +}; + +struct hostent { + char *h_name; * official name of host * + char **h_aliases; * alias list * + int h_addrtype; * host address type * + int h_length; * length of address * + char **h_addr_list; * list of addresses * +} +#define h_addr h_addr_list[0] * for backward compatibility * + +*/ + +Curl_addrinfo *Curl_he2ai(struct hostent *he, int port) +{ + Curl_addrinfo *ai; + Curl_addrinfo *prevai = NULL; + Curl_addrinfo *firstai = NULL; + int i; + + union { + struct in_addr *addr; + char* list; + } curr; + union { + struct sockaddr_in* addr_in; + struct sockaddr* addr; + } address; + + if(!he) + /* no input == no output! */ + return NULL; + + for(i=0; (curr.list = he->h_addr_list[i]); i++) { + + ai = calloc(1, sizeof(Curl_addrinfo) + sizeof(struct sockaddr_in)); + + if(!ai) + break; + + if(!firstai) + /* store the pointer we want to return from this function */ + firstai = ai; + + if(prevai) + /* make the previous entry point to this */ + prevai->ai_next = ai; + + ai->ai_family = AF_INET; /* we only support this */ + ai->ai_socktype = SOCK_STREAM; /* we only support this */ + ai->ai_addrlen = sizeof(struct sockaddr_in); + /* make the ai_addr point to the address immediately following this struct + and use that area to store the address */ + ai->ai_addr = (struct sockaddr *) (ai + 1); + + /* leave the rest of the struct filled with zero */ + + address.addr = ai->ai_addr; /* storage area for this info */ + + memcpy((char *)&(address.addr_in->sin_addr), curr.addr, sizeof(struct in_addr)); + address.addr_in->sin_family = he->h_addrtype; + address.addr_in->sin_port = htons((unsigned short)port); + + prevai = ai; + } + return firstai; +} + +#endif /* CURLRES_IPV4 */ |