diff options
Diffstat (limited to 'sysdeps/posix/getaddrinfo.c')
| -rw-r--r-- | sysdeps/posix/getaddrinfo.c | 412 |
1 files changed, 379 insertions, 33 deletions
diff --git a/sysdeps/posix/getaddrinfo.c b/sysdeps/posix/getaddrinfo.c index fa3bbe4..fc09286 100644 --- a/sysdeps/posix/getaddrinfo.c +++ b/sysdeps/posix/getaddrinfo.c @@ -36,23 +36,27 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. /* This software is Copyright 1996 by Craig Metz, All Rights Reserved. */ #include <assert.h> +#include <ctype.h> #include <errno.h> #include <ifaddrs.h> #include <netdb.h> #include <resolv.h> #include <stdbool.h> #include <stdio.h> +#include <stdio_ext.h> #include <stdlib.h> #include <string.h> -#include <unistd.h> #include <arpa/inet.h> -#include <sys/socket.h> +#include <net/if.h> #include <netinet/in.h> +#include <sys/socket.h> +#include <sys/stat.h> #include <sys/types.h> #include <sys/un.h> #include <sys/utsname.h> -#include <net/if.h> +#include <unistd.h> #include <nsswitch.h> +#include <bits/libc-lock.h> #include <not-cancel.h> #include <nscd/nscd-client.h> #include <nscd/nscd_proto.h> @@ -1161,59 +1165,77 @@ get_scope (const struct sockaddr_storage *ss) } -/* XXX The system administrator should be able to install other - tables. We need to make this configurable. The problem is that - the kernel is also involved since it needs the same table. */ -static const struct prefixlist +struct prefixentry { struct in6_addr prefix; unsigned int bits; int val; -} default_labels[] = +}; + + +/* The label table. */ +static const struct prefixentry *labels; + +/* Default labels. */ +static const struct prefixentry default_labels[] = { /* See RFC 3484 for the details. */ - { { .in6_u = { .u6_addr16 = { 0x0000, 0x0000, 0x0000, 0x0000, - 0x0000, 0x0000, 0x0000, 0x0001 } } }, + { { .in6_u + = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01 } } }, 128, 0 }, - { { .in6_u = { .u6_addr16 = { 0x2002, 0x0000, 0x0000, 0x0000, - 0x0000, 0x0000, 0x0000, 0x0000 } } }, + { { .in6_u + = { .u6_addr8 = { 0x20, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } } }, 16, 2 }, - { { .in6_u = { .u6_addr16 = { 0x0000, 0x0000, 0x0000, 0x0000, - 0x0000, 0x0000, 0x0000, 0x0000 } } }, + { { .in6_u + = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } } }, 96, 3 }, - { { .in6_u = { .u6_addr16 = { 0x0000, 0x0000, 0x0000, 0x0000, - 0x0000, 0xffff, 0x0000, 0x0000 } } }, + { { .in6_u + = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00 } } }, 96, 4 }, - { { .in6_u = { .u6_addr16 = { 0x0000, 0x0000, 0x0000, 0x0000, - 0x0000, 0x0000, 0x0000, 0x0000 } } }, + { { .in6_u + = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } } }, 0, 1 } }; -static const struct prefixlist default_precedence[] = +/* The precedence table. */ +static const struct prefixentry *precedence; + +/* The default precedences. */ +static const struct prefixentry default_precedence[] = { /* See RFC 3484 for the details. */ - { { .in6_u = { .u6_addr16 = { 0x0000, 0x0000, 0x0000, 0x0000, - 0x0000, 0x0000, 0x0000, 0x0001 } } }, + { { .in6_u + = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01 } } }, 128, 50 }, - { { .in6_u = { .u6_addr16 = { 0x2002, 0x0000, 0x0000, 0x0000, - 0x0000, 0x0000, 0x0000, 0x0000 } } }, + { { .in6_u + = { .u6_addr8 = { 0x20, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } } }, 16, 30 }, - { { .in6_u = { .u6_addr16 = { 0x0000, 0x0000, 0x0000, 0x0000, - 0x0000, 0x0000, 0x0000, 0x0000 } } }, + { { .in6_u + = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } } }, 96, 20 }, - { { .in6_u = { .u6_addr16 = { 0x0000, 0x0000, 0x0000, 0x0000, - 0x0000, 0xffff, 0x0000, 0x0000 } } }, + { { .in6_u + = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00 } } }, 96, 100 }, - { { .in6_u = { .u6_addr16 = { 0x0000, 0x0000, 0x0000, 0x0000, - 0x0000, 0x0000, 0x0000, 0x0000 } } }, + { { .in6_u + = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } } }, 0, 40 } }; static int -match_prefix (const struct sockaddr_storage *ss, const struct prefixlist *list, - int default_val) +match_prefix (const struct sockaddr_storage *ss, + const struct prefixentry *list, int default_val) { int idx; struct sockaddr_in6 in6_mem; @@ -1277,7 +1299,7 @@ static int get_label (const struct sockaddr_storage *ss) { /* XXX What is a good default value? */ - return match_prefix (ss, default_labels, INT_MAX); + return match_prefix (ss, labels, INT_MAX); } @@ -1285,7 +1307,7 @@ static int get_precedence (const struct sockaddr_storage *ss) { /* XXX What is a good default value? */ - return match_prefix (ss, default_precedence, 0); + return match_prefix (ss, precedence, 0); } @@ -1482,6 +1504,323 @@ in6aicmp (const void *p1, const void *p2) } +/* Name of the config file for RFC 3484 sorting (for now). */ +#define GAICONF_FNAME "/etc/gai.conf" + + +/* Nozero if we are supposed to reload the config file automatically + whenever it changed. */ +static int gaiconf_reload_flag; + +/* Last modification time. */ +static struct timespec gaiconf_mtime; + + +libc_freeres_fn(fini) +{ + if (labels != default_labels) + { + const struct prefixentry *old = labels; + labels = default_labels; + free ((void *) old); + } + + if (precedence != default_precedence) + { + const struct prefixentry *old = precedence; + precedence = default_precedence; + free ((void *) old); + } +} + + +struct prefixlist +{ + struct prefixentry entry; + struct prefixlist *next; +}; + + +static void +free_prefixlist (struct prefixlist *list) +{ + while (list != NULL) + { + struct prefixlist *oldp = list; + list = list->next; + free (oldp); + } +} + + +static int +prefixcmp (const void *p1, const void *p2) +{ + const struct prefixentry *e1 = (const struct prefixentry *) p1; + const struct prefixentry *e2 = (const struct prefixentry *) p2; + + if (e1->bits < e2->bits) + return 1; + if (e1->bits == e2->bits) + return 0; + return -1; +} + + +static void +gaiconf_init (void) +{ + struct prefixlist *labellist = NULL; + size_t nlabellist = 0; + bool labellist_nullbits = false; + struct prefixlist *precedencelist = NULL; + size_t nprecedencelist = 0; + bool precedencelist_nullbits = false; + + FILE *fp = fopen (GAICONF_FNAME, "rc"); + if (fp != NULL) + { + struct stat64 st; + if (__fxstat64 (_STAT_VER, fileno (fp), &st) != 0) + { + fclose (fp); + goto no_file; + } + + char *line = NULL; + size_t linelen = 0; + + __fsetlocking (fp, FSETLOCKING_BYCALLER); + + while (!feof_unlocked (fp)) + { + ssize_t n = __getline (&line, &linelen, fp); + if (n <= 0) + break; + + /* Handle comments. No escaping possible so this is easy. */ + char *cp = strchr (line, '#'); + if (cp != NULL) + *cp = '\0'; + + cp = line; + while (isspace (*cp)) + ++cp; + + char *cmd = cp; + while (*cp != '\0' && !isspace (*cp)) + ++cp; + size_t cmdlen = cp - cmd; + + if (*cp != '\0') + *cp++ = '\0'; + while (isspace (*cp)) + ++cp; + + char *val1 = cp; + while (*cp != '\0' && !isspace (*cp)) + ++cp; + size_t val1len = cp - cmd; + + /* We always need at least two values. */ + if (val1len == 0) + continue; + + if (*cp != '\0') + *cp++ = '\0'; + while (isspace (*cp)) + ++cp; + + char *val2 = cp; + while (*cp != '\0' && !isspace (*cp)) + ++cp; + + /* Ignore the rest of the line. */ + *cp = '\0'; + + struct prefixlist **listp; + size_t *lenp; + bool *nullbitsp; + switch (cmdlen) + { + case 5: + if (strcmp (cmd, "label") == 0) + { + struct in6_addr prefix; + unsigned long int bits = 128; + unsigned long int val; + char *endp; + + listp = &labellist; + lenp = &nlabellist; + nullbitsp = &labellist_nullbits; + + new_elem: + __set_errno (0); + cp = strchr (val1, '/'); + if (cp != NULL) + *cp++ = '\0'; + if (inet_pton (AF_INET6, val1, &prefix) + && (cp == NULL + || (bits = strtoul (cp, &endp, 10)) != ULONG_MAX + || errno != ERANGE) + && *endp == '\0' + && bits <= INT_MAX + && ((val = strtoul (val2, &endp, 10)) != ULONG_MAX + || errno != ERANGE) + && *endp == '\0' + && val <= INT_MAX) + { + struct prefixlist *newp = malloc (sizeof (*newp)); + if (newp == NULL) + { + free (line); + fclose (fp); + goto no_file; + } + + memcpy (&newp->entry.prefix, &prefix, sizeof (prefix)); + newp->entry.bits = bits; + newp->entry.val = val; + newp->next = *listp; + *listp = newp; + ++*lenp; + *nullbitsp |= bits == 0; + } + } + break; + + case 6: + if (strcmp (cmd, "reload") == 0) + gaiconf_reload_flag = strcmp (val1, "yes") == 0; + break; + + case 10: + if (strcmp (cmd, "precedence") == 0) + { + listp = &precedencelist; + lenp = &nprecedencelist; + nullbitsp = &precedencelist_nullbits; + goto new_elem; + } + break; + } + } + + free (line); + + fclose (fp); + + /* Create the array for the labels. */ + struct prefixentry *new_labels; + if (nlabellist > 0) + { + if (!labellist_nullbits) + ++nlabellist; + new_labels = malloc (nlabellist * sizeof (*new_labels)); + if (new_labels == NULL) + goto no_file; + + int i = nlabellist; + if (!labellist_nullbits) + { + --i; + memset (&new_labels[i].prefix, '\0', sizeof (struct in6_addr)); + new_labels[i].bits = 0; + new_labels[i].val = 1; + } + + struct prefixlist *l = labellist; + while (i-- > 0) + { + new_labels[i] = l->entry; + l = l->next; + } + free_prefixlist (labellist); + + /* Sort the entries so that the most specific ones are at + the beginning. */ + qsort (new_labels, nlabellist, sizeof (*new_labels), prefixcmp); + } + else + new_labels = (struct prefixentry *) default_labels; + + struct prefixentry *new_precedence; + if (nprecedencelist > 0) + { + if (!precedencelist_nullbits) + ++nprecedencelist; + new_precedence = malloc (nprecedencelist * sizeof (*new_precedence)); + if (new_precedence == NULL) + { + if (new_labels != default_labels) + free (new_labels); + goto no_file; + } + + int i = nprecedencelist; + if (!precedencelist_nullbits) + { + --i; + memset (&new_precedence[i].prefix, '\0', + sizeof (struct in6_addr)); + new_precedence[i].bits = 0; + new_precedence[i].val = 40; + } + + struct prefixlist *l = precedencelist; + while (i-- > 0) + { + new_precedence[i] = l->entry; + l = l->next; + } + free_prefixlist (precedencelist); + + /* Sort the entries so that the most specific ones are at + the beginning. */ + qsort (new_precedence, nprecedencelist, sizeof (*new_labels), + prefixcmp); + } + else + new_precedence = (struct prefixentry *) default_precedence; + + /* Now we are ready to replace the values. */ + const struct prefixentry *old = labels; + labels = new_labels; + if (old != default_labels) + free ((void *) old); + + old = precedence; + precedence = new_precedence; + if (old != default_precedence) + free ((void *) old); + + gaiconf_mtime = st.st_mtim; + } + else + { + no_file: + free_prefixlist (labellist); + free_prefixlist (precedencelist); + + /* If we previously read the file but it is gone now, free the + old data and use the builtin one. Leave the reload flag + alone. */ + fini (); + } +} + + +static void +gaiconf_reload (void) +{ + struct stat64 st; + if (__xstat64 (_STAT_VER, GAICONF_FNAME, &st) != 0 + || memcmp (&st.st_mtim, &gaiconf_mtime, sizeof (gaiconf_mtime)) != 0) + gaiconf_init (); +} + + int getaddrinfo (const char *name, const char *service, const struct addrinfo *hints, struct addrinfo **pai) @@ -1661,6 +2000,13 @@ getaddrinfo (const char *name, const char *service, if (naddrs > 1) { + /* Read the config file. */ + __libc_once_define (static, once); + __typeof (once) old_once = once; + __libc_once (once, gaiconf_init); + if (old_once && gaiconf_reload_flag) + gaiconf_reload (); + /* Sort results according to RFC 3484. */ struct sort_result results[nresults]; struct addrinfo *q; |