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Diffstat (limited to 'libcurl/src/lib/hostip4.c')
| -rw-r--r-- | libcurl/src/lib/hostip4.c | 307 |
1 files changed, 307 insertions, 0 deletions
diff --git a/libcurl/src/lib/hostip4.c b/libcurl/src/lib/hostip4.c new file mode 100644 index 0000000..fe6d749 --- /dev/null +++ b/libcurl/src/lib/hostip4.c @@ -0,0 +1,307 @@ +/***************************************************************************
+ * _ _ ____ _
+ * Project ___| | | | _ \| |
+ * / __| | | | |_) | |
+ * | (__| |_| | _ <| |___
+ * \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2015, 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.
+ *
+ ***************************************************************************/
+
+#include "curl_setup.h"
+
+#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 __VMS
+#include <in.h>
+#include <inet.h>
+#endif
+
+#ifdef HAVE_PROCESS_H
+#include <process.h>
+#endif
+
+#include "urldata.h"
+#include "sendf.h"
+#include "hostip.h"
+#include "hash.h"
+#include "share.h"
+#include "strerror.h"
+#include "url.h"
+#include "inet_pton.h"
+#include "curl_printf.h"
+#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 */
+/*
+ * Curl_ipvalid() checks what CURL_IPRESOLVE_* requirements that might've
+ * been set and returns TRUE if they are OK.
+ */
+CURL_STATIC bool Curl_ipvalid(struct connectdata *conn)
+{
+ if(conn->ip_version == CURL_IPRESOLVE_V6)
+ /* An IPv6 address was requested and we can't get/use one */
+ return FALSE;
+
+ return TRUE; /* OK, proceed */
+}
+
+#ifdef CURLRES_SYNCH
+
+/*
+ * 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_STATIC Curl_addrinfo *Curl_getaddrinfo(struct connectdata *conn,
+ const char *hostname,
+ int port,
+ int *waitp)
+{
+ Curl_addrinfo *ai = NULL;
+
+#ifdef CURL_DISABLE_VERBOSE_STRINGS
+ (void)conn;
+#endif
+
+ *waitp = 0; /* synchronous response only */
+
+ ai = Curl_ipv4_resolve_r(hostname, port);
+ if(!ai)
+ infof(conn->data, "Curl_ipv4_resolve_r failed for %s\n", hostname);
+
+ return ai;
+}
+#endif /* CURLRES_SYNCH */
+#endif /* CURLRES_IPV4 */
+
+#if defined(CURLRES_IPV4) && !defined(CURLRES_ARES)
+
+/*
+ * Curl_ipv4_resolve_r() - ipv4 threadsafe resolver function.
+ *
+ * This is used for both synchronous and asynchronous resolver builds,
+ * implying that only threadsafe code and function calls may be used.
+ *
+ */
+Curl_addrinfo *Curl_ipv4_resolve_r(const char *hostname,
+ int port)
+{
+#if !defined(HAVE_GETADDRINFO_THREADSAFE) && defined(HAVE_GETHOSTBYNAME_R_3)
+ int res;
+#endif
+ Curl_addrinfo *ai = NULL;
+ struct hostent *h = NULL;
+ struct in_addr in;
+ struct hostent *buf = NULL;
+
+ 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_GETADDRINFO_THREADSAFE)
+ else {
+ struct addrinfo hints;
+ char sbuf[12];
+ char *sbufptr = NULL;
+
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_family = PF_INET;
+ hints.ai_socktype = SOCK_STREAM;
+ if(port) {
+ snprintf(sbuf, sizeof(sbuf), "%d", port);
+ sbufptr = sbuf;
+ }
+
+ (void)Curl_getaddrinfo_ex(hostname, sbufptr, &hints, &ai);
+
+#elif 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.
+ */
+
+#if defined(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
+#elif defined(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 */
+#elif defined(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_...BYNAME_R_5 || HAVE_...BYNAME_R_6 || HAVE_...BYNAME_R_3 */
+ {
+ h = NULL; /* set return code to NULL */
+ free(buf);
+ }
+#else /* HAVE_GETADDRINFO_THREADSAFE || HAVE_GETHOSTBYNAME_R */
+ /*
+ * Here is code for platforms that don't have a thread safe
+ * getaddrinfo() nor gethostbyname_r() function or for which
+ * gethostbyname() is the preferred one.
+ */
+ else {
+ h = gethostbyname((void*)hostname);
+#endif /* HAVE_GETADDRINFO_THREADSAFE || HAVE_GETHOSTBYNAME_R */
+ }
+
+ if(h) {
+ ai = Curl_he2ai(h, port);
+
+ if(buf) /* used a *_r() function */
+ free(buf);
+ }
+
+ return ai;
+}
+#endif /* defined(CURLRES_IPV4) && !defined(CURLRES_ARES) */
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