/* Returns NULL if successful, otherwise a malloc()'d string describing the
* error. The caller is responsible for freeing the returned string. */
static char * OVS_WARN_UNUSED_RESULT
learn_parse_load_immediate(union mf_subvalue *imm, const char *s,
const char *full_s, struct ofpact_learn_spec *spec,
struct ofpbuf *ofpacts)
{
struct mf_subfield dst;
char *error;
error = mf_parse_subfield(&dst, s);
if (error) {
return error;
}
if (!mf_nxm_header(dst.field->id)) {
return xasprintf("%s: experimenter OXM field '%s' not supported",
full_s, s);
}
if (!bitwise_is_all_zeros(imm, sizeof *imm, dst.n_bits,
(8 * sizeof *imm) - dst.n_bits)) {
return xasprintf("%s: value does not fit into %u bits",
full_s, dst.n_bits);
}
spec->n_bits = dst.n_bits;
spec->src_type = NX_LEARN_SRC_IMMEDIATE;
spec->dst_type = NX_LEARN_DST_LOAD;
spec->dst = dst;
/* Push value last, as this may reallocate 'spec'! */
unsigned int n_bytes = DIV_ROUND_UP(dst.n_bits, 8);
uint8_t *src_imm = ofpbuf_put_zeros(ofpacts, OFPACT_ALIGN(n_bytes));
memcpy(src_imm, &imm->u8[sizeof imm->u8 - n_bytes], n_bytes);
return NULL;
}
/* Returns NULL if successful, otherwise a malloc()'d string describing the
* error. The caller is responsible for freeing the returned string. */
static char * OVS_WARN_UNUSED_RESULT
learn_parse_load_immediate(const char *s, struct ofpact_learn_spec *spec)
{
const char *full_s = s;
const char *arrow = strstr(s, "->");
struct mf_subfield dst;
union mf_subvalue imm;
char *error;
memset(&imm, 0, sizeof imm);
if (s[0] == '0' && (s[1] == 'x' || s[1] == 'X') && arrow) {
const char *in = arrow - 1;
uint8_t *out = imm.u8 + sizeof imm.u8 - 1;
int n = arrow - (s + 2);
int i;
for (i = 0; i < n; i++) {
int hexit = hexit_value(in[-i]);
if (hexit < 0) {
return xasprintf("%s: bad hex digit in value", full_s);
}
out[-(i / 2)] |= i % 2 ? hexit << 4 : hexit;
}
s = arrow;
} else {
ovs_be64 *last_be64 = &imm.be64[ARRAY_SIZE(imm.be64) - 1];
*last_be64 = htonll(strtoull(s, (char **) &s, 0));
}
if (strncmp(s, "->", 2)) {
return xasprintf("%s: missing `->' following value", full_s);
}
s += 2;
error = mf_parse_subfield(&dst, s);
if (error) {
return error;
}
if (!mf_nxm_header(dst.field->id)) {
return xasprintf("%s: experimenter OXM field '%s' not supported",
full_s, s);
}
if (!bitwise_is_all_zeros(&imm, sizeof imm, dst.n_bits,
(8 * sizeof imm) - dst.n_bits)) {
return xasprintf("%s: value does not fit into %u bits",
full_s, dst.n_bits);
}
spec->n_bits = dst.n_bits;
spec->src_type = NX_LEARN_SRC_IMMEDIATE;
spec->src_imm = imm;
spec->dst_type = NX_LEARN_DST_LOAD;
spec->dst = dst;
return NULL;
}
static void
learn_parse_load_immediate(const char *s, struct ofpact_learn_spec *spec)
{
const char *full_s = s;
const char *arrow = strstr(s, "->");
struct mf_subfield dst;
union mf_subvalue imm;
memset(&imm, 0, sizeof imm);
if (s[0] == '0' && (s[1] == 'x' || s[1] == 'X') && arrow) {
const char *in = arrow - 1;
uint8_t *out = imm.u8 + sizeof imm.u8 - 1;
int n = arrow - (s + 2);
int i;
for (i = 0; i < n; i++) {
int hexit = hexit_value(in[-i]);
if (hexit < 0) {
ovs_fatal(0, "%s: bad hex digit in value", full_s);
}
out[-(i / 2)] |= i % 2 ? hexit << 4 : hexit;
}
s = arrow;
} else {
imm.be64[1] = htonll(strtoull(s, (char **) &s, 0));
}
if (strncmp(s, "->", 2)) {
ovs_fatal(0, "%s: missing `->' following value", full_s);
}
s += 2;
s = mf_parse_subfield(&dst, s);
if (*s != '\0') {
ovs_fatal(0, "%s: trailing garbage following destination", full_s);
}
if (!bitwise_is_all_zeros(&imm, sizeof imm, dst.n_bits,
(8 * sizeof imm) - dst.n_bits)) {
ovs_fatal(0, "%s: value does not fit into %u bits",
full_s, dst.n_bits);
}
spec->n_bits = dst.n_bits;
spec->src_type = NX_LEARN_SRC_IMMEDIATE;
spec->src_imm = imm;
spec->dst_type = NX_LEARN_DST_LOAD;
spec->dst = dst;
}
static void
check_bitwise_is_all_zeros(void)
{
int n_loops;
n_loops = 0;
for (n_loops = 0; n_loops < 100; n_loops++) {
ovs_be64 x = htonll(0);
int i;
for (i = 0; i < 64; i++) {
ovs_be64 bit;
int ofs, n;
/* Change a random 0-bit into a 1-bit. */
do {
bit = htonll(UINT64_C(1) << (random_uint32() % 64));
} while (x & bit);
x |= bit;
for (ofs = 0; ofs < 64; ofs++) {
for (n = 0; n <= 64 - ofs; n++) {
bool expect;
bool answer;
expect = (n == 64
? x == 0
: !(x & htonll(((UINT64_C(1) << n) - 1)
<< ofs)));
answer = bitwise_is_all_zeros(&x, sizeof x, ofs, n);
if (expect != answer) {
fprintf(stderr,
"bitwise_is_all_zeros(0x%016"PRIx64",8,%d,%d "
"returned %s instead of %s\n",
ntohll(x), ofs, n,
answer ? "true" : "false",
expect ? "true" : "false");
abort();
}
}
}
}
}
}
/* Returns NULL if successful, otherwise a malloc()'d string describing the
* error. The caller is responsible for freeing the returned string. */
static char * OVS_WARN_UNUSED_RESULT
learn_parse_load_immediate(const char *s, struct ofpact_learn_spec *spec)
{
const char *full_s = s;
struct mf_subfield dst;
union mf_subvalue imm;
char *error;
int err;
err = parse_int_string(s, imm.u8, sizeof imm.u8, (char **) &s);
if (err) {
return xasprintf("%s: too many bits in immediate value", full_s);
}
if (strncmp(s, "->", 2)) {
return xasprintf("%s: missing `->' following value", full_s);
}
s += 2;
error = mf_parse_subfield(&dst, s);
if (error) {
return error;
}
if (!mf_nxm_header(dst.field->id)) {
return xasprintf("%s: experimenter OXM field '%s' not supported",
full_s, s);
}
if (!bitwise_is_all_zeros(&imm, sizeof imm, dst.n_bits,
(8 * sizeof imm) - dst.n_bits)) {
return xasprintf("%s: value does not fit into %u bits",
full_s, dst.n_bits);
}
spec->n_bits = dst.n_bits;
spec->src_type = NX_LEARN_SRC_IMMEDIATE;
spec->src_imm = imm;
spec->dst_type = NX_LEARN_DST_LOAD;
spec->dst = dst;
return NULL;
}
/* Returns NULL if successful, otherwise a malloc()'d string describing the
* error. The caller is responsible for freeing the returned string. */
static char * OVS_WARN_UNUSED_RESULT
learn_parse_spec(const char *orig, char *name, char *value,
const struct ofputil_port_map *port_map,
struct ofpact_learn_spec *spec,
struct ofpbuf *ofpacts, struct match *match)
{
/* Parse destination and check prerequisites. */
struct mf_subfield dst;
char *error = mf_parse_subfield(&dst, name);
bool parse_error = error != NULL;
free(error);
if (!parse_error) {
if (!mf_nxm_header(dst.field->id)) {
return xasprintf("%s: experimenter OXM field '%s' not supported",
orig, name);
}
spec->dst = dst;
spec->n_bits = dst.n_bits;
spec->dst_type = NX_LEARN_DST_MATCH;
/* Parse source and check prerequisites. */
if (value[0] != '\0') {
struct mf_subfield src;
error = mf_parse_subfield(&src, value);
if (error) {
union mf_value imm;
char *imm_error = NULL;
/* Try an immediate value. */
if (dst.ofs == 0 && dst.n_bits == dst.field->n_bits) {
/* Full field value. */
imm_error = mf_parse_value(dst.field, value, port_map,
&imm);
} else {
char *tail;
/* Partial field value. */
if (parse_int_string(value, (uint8_t *)&imm,
dst.field->n_bytes, &tail)
|| *tail != 0) {
imm_error = xasprintf("%s: cannot parse integer value", orig);
}
if (!imm_error &&
!bitwise_is_all_zeros(&imm, dst.field->n_bytes,
dst.n_bits,
dst.field->n_bytes * 8 - dst.n_bits)) {
struct ds ds;
ds_init(&ds);
mf_format(dst.field, &imm, NULL, NULL, &ds);
imm_error = xasprintf("%s: value %s does not fit into %d bits",
orig, ds_cstr(&ds), dst.n_bits);
ds_destroy(&ds);
}
}
if (imm_error) {
char *err = xasprintf("%s: %s value %s cannot be parsed as a subfield (%s) or an immediate value (%s)",
orig, name, value, error, imm_error);
free(error);
free(imm_error);
return err;
}
spec->src_type = NX_LEARN_SRC_IMMEDIATE;
/* Update 'match' to allow for satisfying destination
* prerequisites. */
mf_write_subfield_value(&dst, &imm, match);
/* Push value last, as this may reallocate 'spec'! */
unsigned int imm_bytes = DIV_ROUND_UP(dst.n_bits, 8);
uint8_t *src_imm = ofpbuf_put_zeros(ofpacts,
OFPACT_ALIGN(imm_bytes));
memcpy(src_imm, &imm, imm_bytes);
free(error);
return NULL;
}
spec->src = src;
if (spec->src.n_bits != spec->dst.n_bits) {
return xasprintf("%s: bit widths of %s (%u) and %s (%u) "
"differ", orig, name, spec->src.n_bits, value,
spec->dst.n_bits);
}
} else {
spec->src = spec->dst;
}
spec->src_type = NX_LEARN_SRC_FIELD;
} else if (!strcmp(name, "load")) {
union mf_subvalue imm;
char *tail;
char *dst_value = strstr(value, "->");
if (dst_value == value) {
return xasprintf("%s: missing source before `->' in `%s'", name,
value);
}
if (!dst_value) {
return xasprintf("%s: missing `->' in `%s'", name, value);
}
if (!parse_int_string(value, imm.u8, sizeof imm.u8, (char **) &tail)
&& tail != value) {
if (tail != dst_value) {
return xasprintf("%s: garbage before `->' in `%s'",
name, value);
}
error = learn_parse_load_immediate(&imm, dst_value + 2, value, spec,
ofpacts);
if (error) {
return error;
}
} else {
struct ofpact_reg_move move;
error = nxm_parse_reg_move(&move, value);
if (error) {
return error;
}
spec->n_bits = move.src.n_bits;
spec->src_type = NX_LEARN_SRC_FIELD;
spec->src = move.src;
spec->dst_type = NX_LEARN_DST_LOAD;
spec->dst = move.dst;
}
} else if (!strcmp(name, "output")) {
error = mf_parse_subfield(&spec->src, value);
if (error) {
return error;
}
spec->n_bits = spec->src.n_bits;
spec->src_type = NX_LEARN_SRC_FIELD;
spec->dst_type = NX_LEARN_DST_OUTPUT;
} else {
return xasprintf("%s: unknown keyword %s", orig, name);
}
return NULL;
}
