diff options
Diffstat (limited to 'src/libnm-glib-aux/nm-inet-utils.c')
| -rw-r--r-- | src/libnm-glib-aux/nm-inet-utils.c | 151 |
1 files changed, 111 insertions, 40 deletions
diff --git a/src/libnm-glib-aux/nm-inet-utils.c b/src/libnm-glib-aux/nm-inet-utils.c index 7f710f3527..87fe3ce050 100644 --- a/src/libnm-glib-aux/nm-inet-utils.c +++ b/src/libnm-glib-aux/nm-inet-utils.c @@ -6,6 +6,7 @@ #include <netinet/in.h> #include <arpa/inet.h> +#include <dlfcn.h> /*****************************************************************************/ @@ -266,34 +267,118 @@ nm_ip6_addr_same_prefix_cmp(const struct in6_addr *addr_a, /*****************************************************************************/ -static gboolean -_parse_legacy_addr4(const char *text, in_addr_t *out_addr, GError **error) +static int +_inet_aton(const char *text, in_addr_t *out_addr) { - gs_free char *s_free = NULL; - struct in_addr a1; - guint8 bin[sizeof(a1)]; - char *s; - int i; + /* Call inet_aton() via dlopen. + * + * The inet_aton() API is discouraged, and ABI checkers warn when we call + * it. + * + * We want to use this function, but only for testing/asserting. To avoid + * the ABI checker's complain, dlopen() the symbol. This is not used for + * production. + */ + static gpointer mod_handle = NULL; + static gpointer fcn_sym = NULL; + static gsize initialized = 0; + int (*fcn)(const char *text, struct in_addr *out_addr); + int r; + in_addr_t a; + + if (g_once_init_enter(&initialized)) { + mod_handle = dlopen(NULL, RTLD_LAZY); + if (mod_handle) { + fcn_sym = dlsym(mod_handle, "inet_aton"); + if (!fcn_sym) + dlclose(g_steal_pointer(&mod_handle)); + } + g_once_init_leave(&initialized, 1); + } - if (inet_aton(text, &a1) != 1) { - g_set_error_literal(error, - NM_UTILS_ERROR, - NM_UTILS_ERROR_INVALID_ARGUMENT, - "address invalid according to inet_aton()"); - return FALSE; + if (!fcn_sym) + return -ENOSYS; + + g_assert(mod_handle); + + fcn = fcn_sym; + r = fcn(text, (gpointer) &a); + + if (r != 1) + return -EINVAL; + + NM_SET_OUT(out_addr, a); + return 0; +} + +int +nmtst_inet_aton(const char *text, in_addr_t *out_addr) +{ + return _inet_aton(text, out_addr); +} + +static void +_nm_assert_legacy_addr4(const char *text, in_addr_t addr) +{ +#if NM_MORE_ASSERTS > 20 + char buf1[NM_INET_ADDRSTRLEN]; + char buf2[NM_INET_ADDRSTRLEN]; + int r; + in_addr_t a; + + /* Our legacy parser accepted "text" as "addr". + * + * However, we want to ensure that whatever we parse is also parsed by old + * inet_aton(). So we want to be strictly more strict than inet_aton() in + * what we accept. + */ + + r = _inet_aton(text, &a); + + if (r != 0) { + if (r == -ENOSYS) + return; + g_error("inet_aton(\"%s\") failed with \"%s\", but we expected %s", + text, + nm_strerror_native(-r), + nm_inet4_ntop(addr, buf2)); } - /* OK, inet_aton() accepted the format. That's good, because we want - * to accept IPv4 addresses in octal format, like 255.255.000.000. - * That's what "legacy" means here. inet_pton() doesn't accept those. + if (a != addr) { + g_error("inet_aton(\"%s\") parsed %s, but we expected %s", + text, + nm_inet4_ntop(a, buf1), + nm_inet4_ntop(addr, buf2)); + } +#endif +} + +static gboolean +_parse_legacy_addr4(const char *text, in_addr_t *out_addr, GError **error) +{ + gs_free char *s_free = NULL; + union { + guint8 b[sizeof(in_addr_t)]; + in_addr_t a; + } addr; + char *s; + int i; + + /* inet_pton() does strict parsing of IPv4 address. Good. * - * But inet_aton() also ignores trailing garbage and formats with fewer than - * 4 digits. That is just too crazy and we don't do that. Perform additional checks - * and reject some forms that inet_aton() accepted. + * However, inet_aton() used to accept much more relaxed forms (e.g. octal + * and hex numbers, not having 4 components but fewer, ignore any trailing + * garbage). + * + * Some places where we accept input, we want to be slightly more forgiving + * than inet_pton() and accept some (not all!) forms of what inet_aton() + * would accept. For example, we want to accept 255.000.000.000. + * + * We reimplement that below. * * Note that we still should (of course) accept everything that inet_pton() - * accepts. However this code never gets called if inet_pton() succeeds - * (see below, aside the assertion code). */ + * accepts. This is ensured because the caller only calls this function + * after inet_pton() failed. */ if (NM_STRCHAR_ANY(text, ch, (!(ch >= '0' && ch <= '9') && !NM_IN_SET(ch, '.', 'x')))) { /* We only accepts '.', digits, and 'x' for "0x". */ @@ -306,7 +391,7 @@ _parse_legacy_addr4(const char *text, in_addr_t *out_addr, GError **error) s = nm_memdup_maybe_a(300, text, strlen(text) + 1, &s_free); - for (i = 0; i < G_N_ELEMENTS(bin); i++) { + for (i = 0; i < G_N_ELEMENTS(addr.b); i++) { char *current_token = s; gint32 v; @@ -316,7 +401,7 @@ _parse_legacy_addr4(const char *text, in_addr_t *out_addr, GError **error) s++; } - if ((i == G_N_ELEMENTS(bin) - 1) != (s == NULL)) { + if ((i == G_N_ELEMENTS(addr.b) - 1) != (s == NULL)) { /* Exactly for the last digit, we expect to have no more following token. * But this isn't the case. Abort. */ g_set_error(error, @@ -344,26 +429,12 @@ _parse_legacy_addr4(const char *text, in_addr_t *out_addr, GError **error) return FALSE; } - bin[i] = v; + addr.b[i] = v; } - if (memcmp(bin, &a1, sizeof(bin)) != 0) { - /* our parsing did not agree with what inet_aton() gave. Something - * is wrong. Abort. */ - g_set_error( - error, - NM_UTILS_ERROR, - NM_UTILS_ERROR_INVALID_ARGUMENT, - "inet_aton() result 0x%08x differs from computed value 0x%02hhx%02hhx%02hhx%02hhx", - a1.s_addr, - bin[0], - bin[1], - bin[2], - bin[3]); - return FALSE; - } + _nm_assert_legacy_addr4(text, addr.a); - *out_addr = a1.s_addr; + *out_addr = addr.a; return TRUE; } |