diff options
Diffstat (limited to 'resolv/res_init.c')
| -rw-r--r-- | resolv/res_init.c | 93 |
1 files changed, 64 insertions, 29 deletions
diff --git a/resolv/res_init.c b/resolv/res_init.c index 49fc94595b..e604a0212f 100644 --- a/resolv/res_init.c +++ b/resolv/res_init.c @@ -100,6 +100,7 @@ #include <sys/time.h> #include <sys/types.h> #include <inet/net-internal.h> +#include <errno.h> static void res_setoptions (res_state, const char *, const char *); static uint32_t net_mask (struct in_addr); @@ -121,14 +122,11 @@ is_sort_mask (char ch) return ch == '/' || ch == '&'; } -/* Set up default settings. If the /etc/resolv.conf configuration - file exist, the values there will have precedence. Otherwise, the - server address is set to INADDR_LOOPBACK and the default domain - name comes from gethostname. The RES_OPTIONS and LOCALDOMAIN - environment variables can be used to override some settings. - Return 0 if completes successfully, -1 on error. */ -int -__res_vinit (res_state statp, int preinit) +/* Internal helper function for __res_vinit, to aid with resource + deallocation and error handling. Return true on success, false on + failure. */ +static bool +res_vinit_1 (res_state statp, bool preinit, FILE *fp) { char *cp, **pp; char buf[BUFSIZ]; @@ -203,7 +201,6 @@ __res_vinit (res_state statp, int preinit) && (line[sizeof (name) - 1] == ' ' \ || line[sizeof (name) - 1] == '\t')) - FILE *fp = fopen (_PATH_RESCONF, "rce"); if (fp != NULL) { /* No threads use this stream. */ @@ -302,26 +299,26 @@ __res_vinit (res_state statp, int preinit) struct sockaddr_in6 *sa6; sa6 = malloc (sizeof (*sa6)); - if (sa6 != NULL) - { - sa6->sin6_family = AF_INET6; - sa6->sin6_port = htons (NAMESERVER_PORT); - sa6->sin6_flowinfo = 0; - sa6->sin6_addr = a6; - - sa6->sin6_scope_id = 0; - if (__glibc_likely (el != NULL)) - /* Ignore errors, for backwards - compatibility. */ - __inet6_scopeid_pton - (&a6, el + 1, &sa6->sin6_scope_id); - - statp->nsaddr_list[nserv].sin_family = 0; - statp->_u._ext.nsaddrs[nserv] = sa6; - statp->_u._ext.nssocks[nserv] = -1; - have_serv6 = true; - nserv++; - } + if (sa6 == NULL) + return -1; + + sa6->sin6_family = AF_INET6; + sa6->sin6_port = htons (NAMESERVER_PORT); + sa6->sin6_flowinfo = 0; + sa6->sin6_addr = a6; + + sa6->sin6_scope_id = 0; + if (__glibc_likely (el != NULL)) + /* Ignore errors, for backwards + compatibility. */ + __inet6_scopeid_pton + (&a6, el + 1, &sa6->sin6_scope_id); + + statp->nsaddr_list[nserv].sin_family = 0; + statp->_u._ext.nsaddrs[nserv] = sa6; + statp->_u._ext.nssocks[nserv] = -1; + have_serv6 = true; + nserv++; } } continue; @@ -410,6 +407,44 @@ __res_vinit (res_state statp, int preinit) return 0; } +/* Set up default settings. If the /etc/resolv.conf configuration + file exist, the values there will have precedence. Otherwise, the + server address is set to INADDR_LOOPBACK and the default domain + name comes from gethostname. The RES_OPTIONS and LOCALDOMAIN + environment variables can be used to override some settings. + Return 0 if completes successfully, -1 on error. */ +int +__res_vinit (res_state statp, int preinit) +{ + FILE *fp = fopen (_PATH_RESCONF, "rce"); + if (fp == NULL) + switch (errno) + { + case EACCES: + case EISDIR: + case ELOOP: + case ENOENT: + case ENOTDIR: + case EPERM: + /* Ignore these errors. They are persistent errors caused + by file system contents. */ + break; + default: + /* Other errors refer to resource allocation problems and + need to be handled by the application. */ + return -1; + } + if (!res_vinit_1 (statp, preinit, fp)) + { + /* Deallocate the name server addresses which have been + allocated. */ + for (int n = 0; n < MAXNS; n++) + free (statp->_u._ext.nsaddrs[n]); + return -1; + } + return 0; +} + static void res_setoptions (res_state statp, const char *options, const char *source) { |