diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/common/address.c | 53 | ||||
| -rw-r--r-- | src/common/address.h | 2 | ||||
| -rw-r--r-- | src/test/test_address.c | 4 |
3 files changed, 38 insertions, 21 deletions
diff --git a/src/common/address.c b/src/common/address.c index 3b4be1d601..dbb92759d4 100644 --- a/src/common/address.c +++ b/src/common/address.c @@ -1374,22 +1374,33 @@ 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 #endif -/** Convert <b>*ifr</b>, an ifreq structure array of size <b>buflen</b> +/** Convert <b>*buf</b>, an ifreq structure array of size <b>buflen</b>, * 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 *buf, size_t buflen) { smartlist_t *result = smartlist_new(); + char *end = buf + buflen; + + /* These acrobatics are due to alignment issues which trigger + * undefined behaviour traps on OSX. */ + struct ifreq *r = tor_malloc(IFREQ_SIZE); - struct ifreq *r = (struct ifreq *)ifr; + while (buf < end) { + /* Copy up to IFREQ_SIZE bytes into the struct ifreq, but don't overrun + * buf. */ + memcpy(r, buf, end - buf < IFREQ_SIZE ? end - buf : IFREQ_SIZE); - while ((char *)r < (char *)ifr+buflen) { const struct sockaddr *sa = &r->ifr_addr; tor_addr_t tmp; int valid_sa_family = (sa->sa_family == AF_INET || @@ -1400,9 +1411,10 @@ ifreq_to_smartlist(const struct ifreq *ifr, size_t buflen) if (valid_sa_family && conversion_success) smartlist_add(result, tor_memdup(&tmp, sizeof(tmp))); - r = (struct ifreq *)((char *)r + _SIZEOF_ADDR_IFREQ(*r)); + buf += _SIZEOF_ADDR_IFREQ(*r); } + tor_free(r); return result; } @@ -1415,8 +1427,7 @@ 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 +1437,28 @@ 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 8c6ee5abbb..df835e917a 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 7f7347fa88..424a6352b0 100644 --- a/src/test/test_address.c +++ b/src/test/test_address.c @@ -376,7 +376,7 @@ 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); @@ -399,7 +399,7 @@ 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); |