commit 87a95b02363508dd6d9ce4094801c55d3b364ebf Author: Sebastian Hahn sebastian@torproject.org Date: Thu Feb 12 13:59:31 2015 +0100

Actually get all interface addresses

If we guessed a buffer size too small, we never increased the buffer and tried again

Also simplify the interface of ifreq_to_smartlist a little --- src/common/address.c | 37 +++++++++++++++++++++++-------------- src/common/address.h | 2 +- src/test/test_address.c | 4 ++-- 3 files changed, 26 insertions(+), 17 deletions(-)

diff --git a/src/common/address.c b/src/common/address.c index 3b4be1d..8cdcd84 100644 --- a/src/common/address.c +++ b/src/common/address.c @@ -1374,6 +1374,10 @@ get_interface_addresses_win32(int severity)

#ifdef HAVE_IFCONF_TO_SMARTLIST

+/* Guess how much space we need. There shouldn't be any struct ifreqs + * larger than this, even on OS X where the struct's size is dynamic. */ +#define IFREQ_SIZE 4096 + /* This is defined on Mac OS X */ #ifndef _SIZEOF_ADDR_IFREQ #define _SIZEOF_ADDR_IFREQ sizeof @@ -1383,7 +1387,7 @@ get_interface_addresses_win32(int severity) * into smartlist of <b>tor_addr_t</b> structures. */ STATIC smartlist_t * -ifreq_to_smartlist(const struct ifreq *ifr, size_t buflen) +ifreq_to_smartlist(char *ifr, size_t buflen) { smartlist_t *result = smartlist_new();

@@ -1415,8 +1419,7 @@ get_interface_addresses_ioctl(int severity) { /* Some older unixy systems make us use ioctl(SIOCGIFCONF) */ struct ifconf ifc; - int fd, sz; - void *databuf = NULL; + int fd; smartlist_t *result = NULL;

/* This interface, AFAICT, only supports AF_INET addresses */ @@ -1426,22 +1429,28 @@ get_interface_addresses_ioctl(int severity) goto done; }

- /* Guess how much space we need. */ - ifc.ifc_len = sz = 4096; - databuf = tor_malloc_zero(sz); - ifc.ifc_buf = databuf; + int mult = 1; + ifc.ifc_buf = NULL; + do { + mult *= 2; + ifc.ifc_len = mult * IFREQ_SIZE; + ifc.ifc_buf = tor_realloc(ifc.ifc_buf, ifc.ifc_len);

- if (ioctl(fd, SIOCGIFCONF, &ifc) < 0) { - tor_log(severity, LD_NET, "ioctl failed: %s", strerror(errno)); - close(fd); - goto done; - } + tor_assert(ifc.ifc_buf);

- result = ifreq_to_smartlist(databuf, ifc.ifc_len); + if (ioctl(fd, SIOCGIFCONF, &ifc) < 0) { + tor_log(severity, LD_NET, "ioctl failed: %s", strerror(errno)); + close(fd); + goto done; + } + /* Ensure we have least IFREQ_SIZE bytes unused at the end. Otherwise, we + * don't know if we got everything during ioctl. */ + } while (mult * IFREQ_SIZE - ifc.ifc_len <= IFREQ_SIZE); + result = ifreq_to_smartlist(ifc.ifc_buf, ifc.ifc_len);

done: close(fd); - tor_free(databuf); + tor_free(ifc.ifc_buf); return result; } #endif diff --git a/src/common/address.h b/src/common/address.h index 8c6ee5a..df835e9 100644 --- a/src/common/address.h +++ b/src/common/address.h @@ -287,7 +287,7 @@ STATIC smartlist_t *get_interface_addresses_win32(int severity); #endif

#ifdef HAVE_IFCONF_TO_SMARTLIST -STATIC smartlist_t *ifreq_to_smartlist(const struct ifreq *ifr, +STATIC smartlist_t *ifreq_to_smartlist(char *ifr, size_t buflen); STATIC smartlist_t *get_interface_addresses_ioctl(int severity); #endif diff --git a/src/test/test_address.c b/src/test/test_address.c index f98cc12..c739587 100644 --- a/src/test/test_address.c +++ b/src/test/test_address.c @@ -375,7 +375,7 @@ test_address_ifreq_to_smartlist(void *arg) ifc->ifc_len = sizeof(struct ifreq); ifc->ifc_ifcu.ifcu_req = ifr;

- results = ifreq_to_smartlist((struct ifreq *)ifc->ifc_buf,ifc->ifc_len); + results = ifreq_to_smartlist(ifc->ifc_buf,ifc->ifc_len); tt_int_op(smartlist_len(results),==,1);

tor_addr = smartlist_get(results, 0); @@ -398,7 +398,7 @@ test_address_ifreq_to_smartlist(void *arg) SMARTLIST_FOREACH(results, tor_addr_t *, t, tor_free(t)); smartlist_free(results);

- results = ifreq_to_smartlist((struct ifreq *)ifc->ifc_buf,ifc->ifc_len); + results = ifreq_to_smartlist(ifc->ifc_buf,ifc->ifc_len); tt_int_op(smartlist_len(results),==,2);

tor_addr = smartlist_get(results, 0);