diff options
Diffstat (limited to 'lib/utils.c')
| -rw-r--r-- | lib/utils.c | 1398 |
1 files changed, 1398 insertions, 0 deletions
diff --git a/lib/utils.c b/lib/utils.c new file mode 100644 index 0000000..8b7e127 --- /dev/null +++ b/lib/utils.c @@ -0,0 +1,1398 @@ +/* Copyright (C) CZ.NIC, z.s.p.o. <knot-resolver@labs.nic.cz> + * SPDX-License-Identifier: GPL-3.0-or-later + */ + +#include "lib/utils.h" + +#include "contrib/cleanup.h" +#include "contrib/ucw/mempool.h" +#include "kresconfig.h" +#include "lib/defines.h" +#include "lib/generic/array.h" +#include "lib/module.h" +#include "lib/resolve.h" + +#include <libknot/descriptor.h> +#include <libknot/dname.h> +#include <libknot/rrset-dump.h> +#include <libknot/rrtype/rrsig.h> +#include <libknot/version.h> +#include <uv.h> + +#include <arpa/inet.h> +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/time.h> +#include <sys/stat.h> +#include <sys/statvfs.h> +#include <sys/un.h> + +struct __attribute__((packed)) kr_sockaddr_key { + int family; +}; + +struct __attribute__((packed)) kr_sockaddr_in_key { + int family; + char address[sizeof(((struct sockaddr_in *) NULL)->sin_addr)]; + uint16_t port; +}; + +struct __attribute__((packed)) kr_sockaddr_in6_key { + int family; + char address[sizeof(((struct sockaddr_in6 *) NULL)->sin6_addr)]; + uint32_t scope; + uint16_t port; +}; + +struct __attribute((packed)) kr_sockaddr_un_key { + int family; + char path[sizeof(((struct sockaddr_un *) NULL)->sun_path)]; +}; + +extern inline uint64_t kr_rand_bytes(unsigned int size); + +/* Logging & debugging */ +bool kr_dbg_assertion_abort = DBG_ASSERTION_ABORT; +int kr_dbg_assertion_fork = DBG_ASSERTION_FORK; + +void kr_fail(bool is_fatal, const char *expr, const char *func, const char *file, int line) +{ + const int errno_orig = errno; + if (is_fatal) + kr_log_crit(SYSTEM, "requirement \"%s\" failed in %s@%s:%d\n", expr, func, file, line); + else + kr_log_error(SYSTEM, "assertion \"%s\" failed in %s@%s:%d\n", expr, func, file, line); + + if (is_fatal || (kr_dbg_assertion_abort && !kr_dbg_assertion_fork)) + abort(); + else if (!kr_dbg_assertion_abort || !kr_dbg_assertion_fork) + goto recover; + // We want to fork and abort the child, unless rate-limited. + static uint64_t limited_until = 0; + const uint64_t now = kr_now(); + if (now < limited_until) + goto recover; + if (kr_dbg_assertion_fork > 0) { + // Add jitter +- 25%; in other words: 75% + uniform(0,50%). + // Motivation: if a persistent problem starts happening, desynchronize + // coredumps from different instances as they're not cheap. + limited_until = now + kr_dbg_assertion_fork * 3 / 4 + + kr_dbg_assertion_fork * kr_rand_bytes(1) / 256 / 2; + } + if (fork() == 0) + abort(); +recover: + errno = errno_orig; +} + +/* + * Macros. + */ +#define strlen_safe(x) ((x) ? strlen(x) : 0) + +/** + * @internal Convert 16bit unsigned to string, keeps leading spaces. + * @note Always fills dst length = 5 + * Credit: http://computer-programming-forum.com/46-asm/7aa4b50bce8dd985.htm + */ +static inline int u16tostr(uint8_t *dst, uint16_t num) +{ + uint32_t tmp = num * (((1 << 28) / 10000) + 1) - (num / 4); + for(size_t i = 0; i < 5; i++) { + dst[i] = '0' + (char) (tmp >> 28); + tmp = (tmp & 0x0fffffff) * 10; + } + return 5; +} + +char* kr_strcatdup(unsigned n, ...) +{ + if (n < 1) { + return NULL; + } + + /* Calculate total length */ + size_t total_len = 0; + va_list vl; + va_start(vl, n); + for (unsigned i = 0; i < n; ++i) { + char *item = va_arg(vl, char *); + const size_t new_len = total_len + strlen_safe(item); + if (unlikely(new_len < total_len)) { + va_end(vl); + return NULL; + } + total_len = new_len; + } + va_end(vl); + + /* Allocate result and fill */ + char *result = NULL; + if (total_len > 0) { + if (unlikely(total_len == SIZE_MAX)) return NULL; + result = malloc(total_len + 1); + } + if (result) { + char *stream = result; + va_start(vl, n); + for (unsigned i = 0; i < n; ++i) { + char *item = va_arg(vl, char *); + if (item) { + size_t len = strlen(item); + memcpy(stream, item, len + 1); + stream += len; + } + } + va_end(vl); + } + + return result; +} + +char * kr_absolutize_path(const char *dirname, const char *fname) +{ + if (kr_fails_assert(dirname && fname)) { + errno = EINVAL; + return NULL; + } + char *result; + int aret; + if (dirname[0] == '/') { // absolute path is easier + aret = asprintf(&result, "%s/%s", dirname, fname); + } else { // relative path, but don't resolve symlinks + char buf[PATH_MAX]; + const char *cwd = getcwd(buf, sizeof(buf)); + if (!cwd) + return NULL; // errno has been set already + if (strcmp(dirname, ".") == 0) { + // get rid of one common case of extraneous "./" + aret = asprintf(&result, "%s/%s", cwd, fname); + } else { + aret = asprintf(&result, "%s/%s/%s", cwd, dirname, fname); + } + } + if (aret > 0) + return result; + errno = -aret; + return NULL; +} + +int kr_memreserve(void *baton, void **mem, size_t elm_size, size_t want, size_t *have) +{ + if (*have >= want) { + return 0; + } else { + knot_mm_t *pool = baton; + size_t next_size = array_next_count(elm_size, want, *have); + void *mem_new = mm_alloc(pool, next_size * elm_size); + if (mem_new != NULL) { + if (*mem) { /* 0-length memcpy from NULL isn't technically OK */ + memcpy(mem_new, *mem, (*have)*(elm_size)); + mm_free(pool, *mem); + } + *mem = mem_new; + *have = next_size; + return 0; + } + } + return -1; +} + +static int pkt_recycle(knot_pkt_t *pkt, bool keep_question) +{ + /* The maximum size of a header + query name + (class, type) */ + uint8_t buf[KNOT_WIRE_HEADER_SIZE + KNOT_DNAME_MAXLEN + 2 * sizeof(uint16_t)]; + + /* Save header and the question section */ + size_t base_size = KNOT_WIRE_HEADER_SIZE; + if (keep_question) { + base_size += knot_pkt_question_size(pkt); + } + if (kr_fails_assert(base_size <= sizeof(buf))) return kr_error(EINVAL); + memcpy(buf, pkt->wire, base_size); + + /* Clear the packet and its auxiliary structures */ + knot_pkt_clear(pkt); + + /* Restore header and question section and clear counters */ + pkt->size = base_size; + memcpy(pkt->wire, buf, base_size); + knot_wire_set_qdcount(pkt->wire, keep_question); + knot_wire_set_ancount(pkt->wire, 0); + knot_wire_set_nscount(pkt->wire, 0); + knot_wire_set_arcount(pkt->wire, 0); + + /* Reparse question */ + knot_pkt_begin(pkt, KNOT_ANSWER); + return knot_pkt_parse_question(pkt); +} + +int kr_pkt_recycle(knot_pkt_t *pkt) +{ + return pkt_recycle(pkt, false); +} + +int kr_pkt_clear_payload(knot_pkt_t *pkt) +{ + return pkt_recycle(pkt, knot_wire_get_qdcount(pkt->wire)); +} + +int kr_pkt_put(knot_pkt_t *pkt, const knot_dname_t *name, uint32_t ttl, + uint16_t rclass, uint16_t rtype, const uint8_t *rdata, uint16_t rdlen) +{ + /* LATER(opt.): there's relatively lots of copying, but ATM kr_pkt_put() + * isn't considered to be used in any performance-critical parts (just lua). */ + if (!pkt || !name) { + return kr_error(EINVAL); + } + /* Create empty RR */ + knot_rrset_t rr; + knot_rrset_init(&rr, knot_dname_copy(name, &pkt->mm), rtype, rclass, ttl); + /* Create RDATA */ + knot_rdata_t *rdata_tmp = mm_alloc(&pkt->mm, offsetof(knot_rdata_t, data) + rdlen); + knot_rdata_init(rdata_tmp, rdlen, rdata); + knot_rdataset_add(&rr.rrs, rdata_tmp, &pkt->mm); + mm_free(&pkt->mm, rdata_tmp); /* we're always on mempool for now, but whatever */ + /* Append RR */ + return knot_pkt_put(pkt, 0, &rr, KNOT_PF_FREE); +} + +void kr_pkt_make_auth_header(knot_pkt_t *pkt) +{ + if (kr_fails_assert(pkt && pkt->wire)) return; + knot_wire_clear_ad(pkt->wire); + knot_wire_set_aa(pkt->wire); +} + +const char *kr_inaddr(const struct sockaddr *addr) +{ + if (!addr) { + return NULL; + } + switch (addr->sa_family) { + case AF_INET: return (const char *)&(((const struct sockaddr_in *)addr)->sin_addr); + case AF_INET6: return (const char *)&(((const struct sockaddr_in6 *)addr)->sin6_addr); + default: return NULL; + } +} + +int kr_inaddr_family(const struct sockaddr *addr) +{ + if (!addr) + return AF_UNSPEC; + return addr->sa_family; +} + +int kr_inaddr_len(const struct sockaddr *addr) +{ + if (!addr) { + return kr_error(EINVAL); + } + return kr_family_len(addr->sa_family); +} + +int kr_sockaddr_len(const struct sockaddr *addr) +{ + if (!addr) { + return kr_error(EINVAL); + } + switch (addr->sa_family) { + case AF_INET: return sizeof(struct sockaddr_in); + case AF_INET6: return sizeof(struct sockaddr_in6); + case AF_UNIX: return sizeof(struct sockaddr_un); + default: return kr_error(EINVAL); + } +} + +ssize_t kr_sockaddr_key(struct kr_sockaddr_key_storage *dst, + const struct sockaddr *addr) +{ + kr_require(addr); + + switch (addr->sa_family) { + case AF_INET:; + const struct sockaddr_in *addr_in = (const struct sockaddr_in *) addr; + struct kr_sockaddr_in_key *inkey = (struct kr_sockaddr_in_key *) dst; + inkey->family = AF_INET; + memcpy(&inkey->address, &addr_in->sin_addr, sizeof(inkey->address)); + memcpy(&inkey->port, &addr_in->sin_port, sizeof(inkey->port)); + return sizeof(*inkey); + + case AF_INET6:; + const struct sockaddr_in6 *addr_in6 = (const struct sockaddr_in6 *) addr; + struct kr_sockaddr_in6_key *in6key = (struct kr_sockaddr_in6_key *) dst; + in6key->family = AF_INET6; + memcpy(&in6key->address, &addr_in6->sin6_addr, sizeof(in6key->address)); + memcpy(&in6key->port, &addr_in6->sin6_port, sizeof(in6key->port)); + if (kr_sockaddr_link_local(addr)) + memcpy(&in6key->scope, &addr_in6->sin6_scope_id, sizeof(in6key->scope)); + else + in6key->scope = 0; + return sizeof(*in6key); + + case AF_UNIX:; + const struct sockaddr_un *addr_un = (const struct sockaddr_un *) addr; + struct kr_sockaddr_un_key *unkey = (struct kr_sockaddr_un_key *) dst; + unkey->family = AF_UNIX; + size_t pathlen = strnlen(addr_un->sun_path, sizeof(unkey->path)); + if (pathlen == 0 || pathlen >= sizeof(unkey->path)) { + /* Abstract sockets are not supported - we would need + * to also supply a length value for the abstract + * pathname. + * + * UNIX socket path should be null-terminated. + * + * See unix(7). */ + return kr_error(EINVAL); + } + + pathlen += 1; /* Include null-terminator */ + strncpy(unkey->path, addr_un->sun_path, pathlen); + return offsetof(struct kr_sockaddr_un_key, path) + pathlen; + + default: + return kr_error(EAFNOSUPPORT); + } +} + +struct sockaddr *kr_sockaddr_from_key(struct sockaddr_storage *dst, + const char *key) +{ + kr_require(key); + + switch (((struct kr_sockaddr_key *) key)->family) { + case AF_INET:; + const struct kr_sockaddr_in_key *inkey = (struct kr_sockaddr_in_key *) key; + struct sockaddr_in *addr_in = (struct sockaddr_in *) dst; + addr_in->sin_family = AF_INET; + memcpy(&addr_in->sin_addr, &inkey->address, sizeof(inkey->address)); + memcpy(&addr_in->sin_port, &inkey->port, sizeof(inkey->port)); + return (struct sockaddr *) addr_in; + + case AF_INET6:; + const struct kr_sockaddr_in6_key *in6key = (struct kr_sockaddr_in6_key *) key; + struct sockaddr_in6 *addr_in6 = (struct sockaddr_in6 *) dst; + addr_in6->sin6_family = AF_INET6; + memcpy(&addr_in6->sin6_addr, &in6key->address, sizeof(in6key->address)); + memcpy(&addr_in6->sin6_port, &in6key->port, sizeof(in6key->port)); + memcpy(&addr_in6->sin6_scope_id, &in6key->scope, sizeof(in6key->scope)); + return (struct sockaddr *) addr_in6; + + case AF_UNIX:; + const struct kr_sockaddr_un_key *unkey = (struct kr_sockaddr_un_key *) key; + struct sockaddr_un *addr_un = (struct sockaddr_un *) dst; + addr_un->sun_family = AF_UNIX; + strncpy(addr_un->sun_path, unkey->path, sizeof(unkey->path)); + return (struct sockaddr *) addr_un; + + default: + kr_assert(false); + return NULL; + } +} + +bool kr_sockaddr_key_same_addr(const char *key_a, const char *key_b) +{ + const struct kr_sockaddr_in6_key *kkey_a = (struct kr_sockaddr_in6_key *) key_a; + const struct kr_sockaddr_in6_key *kkey_b = (struct kr_sockaddr_in6_key *) key_b; + + if (kkey_a->family != kkey_b->family) + return false; + + ptrdiff_t offset; + switch (kkey_a->family) { + case AF_INET: + offset = offsetof(struct kr_sockaddr_in_key, address); + break; + case AF_INET6: + if (unlikely(kkey_a->scope != kkey_b->scope)) + return false; + offset = offsetof(struct kr_sockaddr_in6_key, address); + break; + + case AF_UNIX:; + const struct kr_sockaddr_un_key *unkey_a = + (struct kr_sockaddr_un_key *) key_a; + const struct kr_sockaddr_un_key *unkey_b = + (struct kr_sockaddr_un_key *) key_b; + + return strncmp(unkey_a->path, unkey_b->path, + sizeof(unkey_a->path)) == 0; + + default: + kr_assert(false); + return false; + } + + size_t len = kr_family_len(kkey_a->family); + return memcmp(key_a + offset, key_b + offset, len) == 0; +} + +int kr_sockaddr_cmp(const struct sockaddr *left, const struct sockaddr *right) +{ + if (!left || !right) { + return kr_error(EINVAL); + } + if (left->sa_family != right->sa_family) { + return kr_error(EFAULT); + } + if (left->sa_family == AF_INET) { + struct sockaddr_in *left_in = (struct sockaddr_in *)left; + struct sockaddr_in *right_in = (struct sockaddr_in *)right; + if (left_in->sin_addr.s_addr != right_in->sin_addr.s_addr) { + return kr_error(EFAULT); + } + if (left_in->sin_port != right_in->sin_port) { + return kr_error(EFAULT); + } + } else if (left->sa_family == AF_INET6) { + struct sockaddr_in6 *left_in6 = (struct sockaddr_in6 *)left; + struct sockaddr_in6 *right_in6 = (struct sockaddr_in6 *)right; + if (memcmp(&left_in6->sin6_addr, &right_in6->sin6_addr, + sizeof(struct in6_addr)) != 0) { + return kr_error(EFAULT); + } + if (left_in6->sin6_port != right_in6->sin6_port) { + return kr_error(EFAULT); + } + } else { + return kr_error(ENOENT); + } + return kr_ok(); +} + +uint16_t kr_inaddr_port(const struct sockaddr *addr) +{ + if (!addr) { + return 0; + } + switch (addr->sa_family) { + case AF_INET: return ntohs(((const struct sockaddr_in *)addr)->sin_port); + case AF_INET6: return ntohs(((const struct sockaddr_in6 *)addr)->sin6_port); + default: return 0; + } +} + +void kr_inaddr_set_port(struct sockaddr *addr, uint16_t port) +{ + if (!addr) { + return; + } + switch (addr->sa_family) { + case AF_INET: + ((struct sockaddr_in *)addr)->sin_port = htons(port); + break; + case AF_INET6: + ((struct sockaddr_in6 *)addr)->sin6_port = htons(port); + break; + default: + break; + } +} + +int kr_inaddr_str(const struct sockaddr *addr, char *buf, size_t *buflen) +{ + if (!addr) { + return kr_error(EINVAL); + } + return kr_ntop_str(addr->sa_family, kr_inaddr(addr), kr_inaddr_port(addr), + buf, buflen); +} + +int kr_ntop_str(int family, const void *src, uint16_t port, char *buf, size_t *buflen) +{ + if (!src || !buf || !buflen) { + return kr_error(EINVAL); + } + + if (!inet_ntop(family, src, buf, *buflen)) { + return kr_error(errno); + } + const int len = strlen(buf); + const int len_need = len + 1 + 5 + 1; + if (len_need > *buflen) { + *buflen = len_need; + return kr_error(ENOSPC); + } + *buflen = len_need; + buf[len] = '#'; + u16tostr((uint8_t *)&buf[len + 1], port); + buf[len_need - 1] = 0; + return kr_ok(); +} + +char *kr_straddr(const struct sockaddr *addr) +{ + if (kr_fails_assert(addr)) return NULL; + static char str[KR_STRADDR_MAXLEN + 1] = {0}; + if (addr->sa_family == AF_UNIX) { + strncpy(str, ((struct sockaddr_un *)addr)->sun_path, sizeof(str) - 1); + return str; + } + size_t len = KR_STRADDR_MAXLEN; + int ret = kr_inaddr_str(addr, str, &len); + return ret != kr_ok() || len == 0 ? NULL : str; +} + +int kr_straddr_family(const char *addr) +{ + if (!addr) { + return kr_error(EINVAL); + } + if (addr[0] == '/') { + return AF_UNIX; + } + if (strchr(addr, ':')) { + return AF_INET6; + } + if (strchr(addr, '.')) { + return AF_INET; + } + return kr_error(EINVAL); +} + +int kr_family_len(int family) +{ + switch (family) { + case AF_INET: return sizeof(struct in_addr); + case AF_INET6: return sizeof(struct in6_addr); + default: return kr_error(EINVAL); + } +} + +struct sockaddr * kr_straddr_socket(const char *addr, int port, knot_mm_t *pool) +{ + switch (kr_straddr_family(addr)) { + case AF_INET: { + struct sockaddr_in *res = mm_alloc(pool, sizeof(*res)); + if (uv_ip4_addr(addr, port, res) >= 0) { + return (struct sockaddr *)res; + } else { + mm_free(pool, res); + return NULL; + } + } + case AF_INET6: { + struct sockaddr_in6 *res = mm_alloc(pool, sizeof(*res)); + if (uv_ip6_addr(addr, port, res) >= 0) { + return (struct sockaddr *)res; + } else { + mm_free(pool, res); + return NULL; + } + } + case AF_UNIX: { + struct sockaddr_un *res; + const size_t alen = strlen(addr) + 1; + if (alen > sizeof(res->sun_path)) { + return NULL; + } + res = mm_alloc(pool, sizeof(*res)); + res->sun_family = AF_UNIX; + memcpy(res->sun_path, addr, alen); + return (struct sockaddr *)res; + } + default: + return NULL; + } +} + +int kr_straddr_subnet(void *dst, const char *addr) +{ + if (!dst || !addr) { + return kr_error(EINVAL); + } + /* Parse subnet */ + int bit_len = 0; + int family = kr_straddr_family(addr); + if (family != AF_INET && family != AF_INET6) + return kr_error(EINVAL); + const int max_len = (family == AF_INET6) ? 128 : 32; + auto_free char *addr_str = strdup(addr); + char *subnet = strchr(addr_str, '/'); + if (subnet) { + *subnet = '\0'; + subnet += 1; + bit_len = strtol(subnet, NULL, 10); + /* Check client subnet length */ + if (bit_len < 0 || bit_len > max_len) { + return kr_error(ERANGE); + } + } else { + /* No subnet, use maximal subnet length. */ + bit_len = max_len; + } + /* Parse address */ + int ret = inet_pton(family, addr_str, dst); + if (ret != 1) { + return kr_error(EILSEQ); + } + + return bit_len; +} + +int kr_straddr_split(const char *instr, char ipaddr[static restrict (INET6_ADDRSTRLEN + 1)], + uint16_t *port) +{ + if (kr_fails_assert(instr && ipaddr && port)) return kr_error(EINVAL); + /* Find where port number starts. */ + const char *p_start = strchr(instr, '@'); + if (!p_start) + p_start = strchr(instr, '#'); + if (p_start) { /* Get and check the port number. */ + if (p_start[1] == '\0') /* Don't accept empty port string. */ + return kr_error(EILSEQ); + char *p_end; + long p = strtol(p_start + 1, &p_end, 10); + if (*p_end != '\0' || p <= 0 || p > UINT16_MAX) + return kr_error(EILSEQ); + *port = p; + } + /* Copy the address. */ + const size_t addrlen = p_start ? p_start - instr : strlen(instr); + if (addrlen > INET6_ADDRSTRLEN) + return kr_error(EILSEQ); + memcpy(ipaddr, instr, addrlen); + ipaddr[addrlen] = '\0'; + return kr_ok(); +} + +int kr_straddr_join(const char *addr, uint16_t port, char *buf, size_t *buflen) +{ + if (!addr || !buf || !buflen) { + return kr_error(EINVAL); + } + + struct sockaddr_storage ss; + int family = kr_straddr_family(addr); + if (family == kr_error(EINVAL) || inet_pton(family, addr, &ss) != 1) { + return kr_error(EINVAL); + } + + int len = strlen(addr); + if (len + 6 >= *buflen) { + return kr_error(ENOSPC); + } + + memcpy(buf, addr, len + 1); + buf[len] = '#'; + u16tostr((uint8_t *)&buf[len + 1], port); + len += 6; + buf[len] = 0; + *buflen = len; + + return kr_ok(); +} + +int kr_bitcmp(const char *a, const char *b, int bits) +{ + /* We're using the function from lua directly, so at least for now + * we avoid crashing on bogus inputs. Meaning: NULL is ordered before + * anything else, and negative length is the same as zero. + * TODO: review the call sites and probably remove the checks. */ + if (bits <= 0 || (!a && !b)) { + return 0; + } else if (!a) { + return -1; + } else if (!b) { + return 1; + } + + kr_require((a && b && bits >= 0) || bits == 0); + /* Compare part byte-divisible part. */ + const size_t chunk = bits / 8; + int ret = memcmp(a, b, chunk); + if (ret != 0) { + return ret; + } + a += chunk; + b += chunk; + bits -= chunk * 8; + /* Compare last partial byte address block. */ + if (bits > 0) { + const size_t shift = (8 - bits); + ret = ((uint8_t)(*a >> shift) - (uint8_t)(*b >> shift)); + } + return ret; +} + +void kr_bitmask(unsigned char *a, size_t a_len, int bits) +{ + if (bits < 0 || !a || !a_len) { + return; + } + + size_t i = bits / 8; + const size_t mid_bits = 8 - (bits % 8); + const unsigned char mask = 0xFF << mid_bits; + if (i < a_len) + a[i] &= mask; + + for (++i; i < a_len; ++i) + a[i] = 0; +} + +int kr_rrkey(char *key, uint16_t class, const knot_dname_t *owner, + uint16_t type, uint16_t additional) +{ + if (!key || !owner) { + return kr_error(EINVAL); + } + uint8_t *key_buf = (uint8_t *)key; + int ret = u16tostr(key_buf, class); + if (ret <= 0) { + return ret; + } + key_buf += ret; + ret = knot_dname_to_wire(key_buf, owner, KNOT_DNAME_MAXLEN); + if (ret <= 0) { + return ret; + } + knot_dname_to_lower(key_buf); + key_buf += ret - 1; + ret = u16tostr(key_buf, type); + if (ret <= 0) { + return ret; + } + key_buf += ret; + ret = u16tostr(key_buf, additional); + if (ret <= 0) { + return ret; + } + key_buf[ret] = '\0'; + return (char *)&key_buf[ret] - key; +} + +/** Return whether two RRsets match, i.e. would form the same set; see ranked_rr_array_t */ +static inline bool rrsets_match(const knot_rrset_t *rr1, const knot_rrset_t *rr2) +{ + bool match = rr1->type == rr2->type && rr1->rclass == rr2->rclass; + if (match && rr2->type == KNOT_RRTYPE_RRSIG) { + match = match && knot_rrsig_type_covered(rr1->rrs.rdata) + == knot_rrsig_type_covered(rr2->rrs.rdata); + } + match = match && knot_dname_is_equal(rr1->owner, rr2->owner); + return match; +} + +/** Ensure that an index in a ranked array won't cause "duplicate" RRsets on wire. + * + * Other entries that would form the same RRset get to_wire = false. + * See also rrsets_match. + */ +static int to_wire_ensure_unique(ranked_rr_array_t *array, size_t index) +{ + if (kr_fails_assert(array && index < array->len)) return kr_error(EINVAL); + + const struct ranked_rr_array_entry *e0 = array->at[index]; + if (!e0->to_wire) { + return kr_ok(); + } + + for (ssize_t i = array->len - 1; i >= 0; --i) { + /* ^ iterate backwards, as the end is more likely in CPU caches */ + struct ranked_rr_array_entry *ei = array->at[i]; + if (ei->qry_uid == e0->qry_uid /* assumption: no duplicates within qry */ + || !ei->to_wire /* no use for complex comparison if @to_wire */ + ) { + continue; + } + if (rrsets_match(ei->rr, e0->rr)) { + ei->to_wire = false; + } + } + return kr_ok(); +} + +/* Implementation overview of _add() and _finalize(): + * - for rdata we just maintain a list of pointers (in knot_rrset_t::additional) + * - we only construct the final rdataset at the end (and thus more efficiently) + */ +typedef array_t(knot_rdata_t *) rdata_array_t; +int kr_ranked_rrarray_add(ranked_rr_array_t *array, const knot_rrset_t *rr, + uint8_t rank, bool to_wire, uint32_t qry_uid, knot_mm_t *pool) +{ + /* From normal packet parser we always get RRs one by one, + * but cache and prefil modules (also) feed us larger RRsets. */ + kr_assert(rr->rrs.count >= 1); + /* Check if another rrset with the same + * rclass/type/owner combination exists within current query + * and merge if needed */ + for (ssize_t i = array->len - 1; i >= 0; --i) { + ranked_rr_array_entry_t *stashed = array->at[i]; + if (stashed->yielded) { + break; + } + if (stashed->qry_uid != qry_uid) { + break; + /* We do not guarantee merging RRs "across" any point that switched + * to processing a different upstream packet (i.e. qry_uid). + * In particular, iterator never returns KR_STATE_YIELD. */ + } + if (!rrsets_match(stashed->rr, rr)) { + continue; + } + /* Found the entry to merge with. Check consistency and merge. */ + if (kr_fails_assert(stashed->rank == rank && !stashed->cached && stashed->in_progress)) + return kr_error(EEXIST); + + /* It may happen that an RRset is first considered useful + * (to_wire = false, e.g. due to being part of glue), + * and later we may find we also want it in the answer. */ + stashed->to_wire = stashed->to_wire || to_wire; + + /* We just add the reference into this in_progress RRset. */ + rdata_array_t *ra = stashed->rr->additional; + if (ra == NULL) { + /* RRset not in array format yet -> convert it. */ + ra = stashed->rr->additional = mm_alloc(pool, sizeof(*ra)); + if (!ra) { + return kr_error(ENOMEM); + } + array_init(*ra); + int ret = array_reserve_mm(*ra, stashed->rr->rrs.count + rr->rrs.count, + kr_memreserve, pool); + if (ret) { + return kr_error(ret); + } + knot_rdata_t *r_it = stashed->rr->rrs.rdata; + for (int ri = 0; ri < stashed->rr->rrs.count; + ++ri, r_it = knot_rdataset_next(r_it)) { + kr_require(array_push(*ra, r_it) >= 0); + } + } else { + int ret = array_reserve_mm(*ra, ra->len + rr->rrs.count, + kr_memreserve, pool); + if (ret) { + return kr_error(ret); + } + } + /* Append to the array. */ + knot_rdata_t *r_it = rr->rrs.rdata; + for (int ri = 0; ri < rr->rrs.count; + ++ri, r_it = knot_rdataset_next(r_it)) { + kr_require(array_push(*ra, r_it) >= 0); + } + return i; + } + + /* No stashed rrset found, add */ + int ret = array_reserve_mm(*array, array->len + 1, kr_memreserve, pool); + if (ret) { + return kr_error(ret); + } + + ranked_rr_array_entry_t *entry = mm_calloc(pool, 1, sizeof(*entry)); + if (!entry) { + return kr_error(ENOMEM); + } + + knot_rrset_t *rr_new = knot_rrset_new(rr->owner, rr->type, rr->rclass, rr->ttl, pool); + if (!rr_new) { + mm_free(pool, entry); + return kr_error(ENOMEM); + } + rr_new->rrs = rr->rrs; + if (kr_fails_assert(rr_new->additional == NULL)) { + mm_free(pool, entry); + return kr_error(EINVAL); + } + + entry->qry_uid = qry_uid; + entry->rr = rr_new; + entry->rank = rank; + entry->to_wire = to_wire; + entry->in_progress = true; + if (array_push(*array, entry) < 0) { + /* Silence coverity. It shouldn't be possible to happen, + * due to the array_reserve_mm call above. */ + mm_free(pool, entry); + return kr_error(ENOMEM); + } + + ret = to_wire_ensure_unique(array, array->len - 1); + if (ret < 0) return ret; + return array->len - 1; +} + +/** Comparator for qsort() on an array of knot_data_t pointers. */ +static int rdata_p_cmp(const void *rp1, const void *rp2) +{ + /* Just correct types of the parameters and pass them dereferenced. */ + const knot_rdata_t + *const *r1 = rp1, + *const *r2 = rp2; + return knot_rdata_cmp(*r1, *r2); +} +int kr_ranked_rrarray_finalize(ranked_rr_array_t *array, uint32_t qry_uid, knot_mm_t *pool) +{ + for (ssize_t array_i = array->len - 1; array_i >= 0; --array_i) { + ranked_rr_array_entry_t *stashed = array->at[array_i]; + if (stashed->qry_uid != qry_uid) { + continue; /* We apparently can't always short-cut the cycle. */ + } + if (!stashed->in_progress) { + continue; + } + rdata_array_t *ra = stashed->rr->additional; + if (!ra) { + /* No array, so we just need to copy the rdataset. */ + knot_rdataset_t *rds = &stashed->rr->rrs; + knot_rdataset_t tmp = *rds; + int ret = knot_rdataset_copy(rds, &tmp, pool); + if (ret) { + return kr_error(ret); + } + } else { + /* Multiple RRs; first: sort the array. */ + stashed->rr->additional = NULL; + qsort(ra->at, ra->len, sizeof(ra->at[0]), rdata_p_cmp); + /* Prune duplicates: NULL all except the last instance. */ + int dup_count = 0; + for (int i = 0; i + 1 < ra->len; ++i) { + if (knot_rdata_cmp(ra->at[i], ra->at[i + 1]) == 0) { + ra->at[i] = NULL; + ++dup_count; + kr_log_q(NULL, ITERATOR, "deleted duplicate RR\n"); + } + } + /* Prepare rdataset, except rdata contents. */ + knot_rdataset_t *rds = &stashed->rr->rrs; + rds->size = 0; + for (int i = 0; i < ra->len; ++i) { + if (ra->at[i]) { + rds->size += knot_rdata_size(ra->at[i]->len); + } + } + rds->count = ra->len - dup_count; + if (rds->size) { + rds->rdata = mm_alloc(pool, rds->size); + if (!rds->rdata) { + return kr_error(ENOMEM); + } + } else { + rds->rdata = NULL; + } + /* Everything is ready; now just copy all the rdata. */ + uint8_t *raw_it = (uint8_t *)rds->rdata; + for (int i = 0; i < ra->len; ++i) { + if (ra->at[i] && rds->size/*linters*/) { + const int size = knot_rdata_size(ra->at[i]->len); + memcpy(raw_it, ra->at[i], size); + raw_it += size; + } + } + if (kr_fails_assert(raw_it == (uint8_t *)rds->rdata + rds->size)) + return kr_error(EINVAL); + } + stashed->in_progress = false; + } + return kr_ok(); +} + + +int kr_ranked_rrarray_set_wire(ranked_rr_array_t *array, bool to_wire, + uint32_t qry_uid, bool check_dups, + bool (*extraCheck)(const ranked_rr_array_entry_t *)) +{ + for (size_t i = 0; i < array->len; ++i) { + ranked_rr_array_entry_t *entry = array->at[i]; + if (entry->qry_uid != qry_uid) { + continue; + } + if (extraCheck != NULL && !extraCheck(entry)) { + continue; + } + entry->to_wire = to_wire; + if (check_dups) { + int ret = to_wire_ensure_unique(array, i); + if (ret) return ret; + } + } + return kr_ok(); +} + + +static char *callprop(struct kr_module *module, const char *prop, const char *input, void *env) +{ + if (!module || !module->props || !prop) { + return NULL; + } + for (const struct kr_prop *p = module->props; p && p->name; ++p) { + if (p->cb != NULL && strcmp(p->name, prop) == 0) { + return p->cb(env, module, input); + } + } + return NULL; +} + +char *kr_module_call(struct kr_context *ctx, const char *module, const char *prop, const char *input) +{ + if (!ctx || !ctx->modules || !module || !prop) { + return NULL; + } + module_array_t *mod_list = ctx->modules; + for (size_t i = 0; i < mod_list->len; ++i) { + struct kr_module *mod = mod_list->at[i]; + if (strcmp(mod->name, module) == 0) { + return callprop(mod, prop, input, ctx); + } + } + return NULL; +} + +static void flags_to_str(char *dst, const knot_pkt_t *pkt, size_t maxlen) +{ + int offset = 0; + int ret = 0; + struct { + uint8_t (*get) (const uint8_t *packet); + char name[3]; + } flag[7] = { + {knot_wire_get_qr, "qr"}, + {knot_wire_get_aa, "aa"}, + {knot_wire_get_rd, "rd"}, + {knot_wire_get_ra, "ra"}, + {knot_wire_get_tc, "tc"}, + {knot_wire_get_ad, "ad"}, + {knot_wire_get_cd, "cd"} + }; + for (int i = 0; i < 7; ++i) { + if (!flag[i].get(pkt->wire)) { + continue; + } + ret = snprintf(dst + offset, maxlen, "%s ", flag[i].name); + if (ret <= 0 || ret >= maxlen) { + dst[0] = 0; + return; + } + offset += ret; + maxlen -= ret; + } + dst[offset] = 0; +} + +static char *print_section_opt(struct mempool *mp, char *endp, const knot_rrset_t *rr, const uint8_t rcode) +{ + uint8_t errcode = knot_edns_get_ext_rcode(rr); + uint16_t ext_rcode_id = knot_edns_whole_rcode(errcode, rcode); + const char *ext_rcode_str = "Unused"; + const knot_lookup_t *ext_rcode; + + if (errcode > 0) { + ext_rcode = knot_lookup_by_id(knot_rcode_names, ext_rcode_id); + if (ext_rcode != NULL) { + ext_rcode_str = ext_rcode->name; + } else { + ext_rcode_str = "Unknown"; + } + } + + return mp_printf_append(mp, endp, + ";; EDNS PSEUDOSECTION:\n;; " + "Version: %u; flags: %s; UDP size: %u B; ext-rcode: %s\n\n", + knot_edns_get_version(rr), + (knot_edns_do(rr) != 0) ? "do" : "", + knot_edns_get_payload(rr), + ext_rcode_str); + +} + +/** + * Detect if qname contains an uppercase letter. + */ +static bool qname_has_uppercase(const knot_dname_t *qname) { + const int len = knot_dname_size(qname) - 1; /* skip root label at the end */ + for (int i = 1; i < len; ++i) { /* skip first length byte */ + /* Note: this relies on the fact that correct label lengths + * can't pass this test by "luck" and that correctness + * is checked earlier by packet parser. */ + if (qname[i] >= 'A' && qname[i] <= 'Z') + return true; + } + return false; +} + +char *kr_pkt_text(const knot_pkt_t *pkt) +{ + if (!pkt) { + return NULL; + } + + struct mempool *mp = mp_new(512); + + static const char * snames[] = { + ";; ANSWER SECTION", ";; AUTHORITY SECTION", ";; ADDITIONAL SECTION" + }; + char flags[32]; + uint8_t pkt_rcode = knot_wire_get_rcode(pkt->wire); + uint8_t pkt_opcode = knot_wire_get_opcode(pkt->wire); + const char *rcode_str = "Unknown"; + const char *opcode_str = "Unknown"; + const knot_lookup_t *rcode = knot_lookup_by_id(knot_rcode_names, pkt_rcode); + const knot_lookup_t *opcode = knot_lookup_by_id(knot_opcode_names, pkt_opcode); + uint16_t qry_id = knot_wire_get_id(pkt->wire); + uint16_t qdcount = knot_wire_get_qdcount(pkt->wire); + + if (rcode != NULL) { + rcode_str = rcode->name; + } + if (opcode != NULL) { + opcode_str = opcode->name; + } + flags_to_str(flags, pkt, sizeof(flags)); + + char *ptr = mp_printf(mp, + ";; ->>HEADER<<- opcode: %s; status: %s; id: %hu\n" + ";; Flags: %s QUERY: %hu; ANSWER: %hu; " + "AUTHORITY: %hu; ADDITIONAL: %hu\n\n", + opcode_str, rcode_str, qry_id, + flags, + qdcount, + knot_wire_get_ancount(pkt->wire), + knot_wire_get_nscount(pkt->wire), + knot_wire_get_arcount(pkt->wire)); + + if (knot_pkt_has_edns(pkt)) { + ptr = print_section_opt(mp, ptr, pkt->opt_rr, knot_wire_get_rcode(pkt->wire)); + } + + if (qdcount == 1) { + KR_DNAME_GET_STR(qname, knot_pkt_qname(pkt)); + KR_RRTYPE_GET_STR(rrtype, knot_pkt_qtype(pkt)); + const char *qnwarn; + if (qname_has_uppercase(knot_pkt_qname(pkt))) + qnwarn = \ +"; WARNING! Uppercase letters indicate positions with letter case mismatches!\n" +"; Normally you should see all-lowercase qname here.\n"; + else + qnwarn = ""; + ptr = mp_printf_append(mp, ptr, ";; QUESTION SECTION\n%s%s\t\t%s\n", qnwarn, qname, rrtype); + } else if (qdcount > 1) { + ptr = mp_printf_append(mp, ptr, ";; Warning: unsupported QDCOUNT %hu\n", qdcount); + } + + for (knot_section_t i = KNOT_ANSWER; i <= KNOT_ADDITIONAL; ++i) { + const knot_pktsection_t *sec = knot_pkt_section(pkt, i); + if (sec->count == 0) { + continue; + } + + ptr = mp_printf_append(mp, ptr, "\n%s\n", snames[i - KNOT_ANSWER]); + for (unsigned k = 0; k < sec->count; ++k) { + const knot_rrset_t *rr = knot_pkt_rr(sec, k); + if (rr->type == KNOT_RRTYPE_OPT) { + continue; + } + auto_free char *rr_text = kr_rrset_text(rr); + ptr = mp_printf_append(mp, ptr, "%s", rr_text); + } + } + + /* Close growing buffer and duplicate result before deleting */ + char *result = strdup(ptr); + mp_delete(mp); + return result; +} + +const knot_dump_style_t KR_DUMP_STYLE_DEFAULT = { /* almost all = false, */ + .show_ttl = true, +#if KNOT_VERSION_HEX >= 0x030200 + .human_timestamp = true, +#else + .human_tmstamp = true, +#endif +}; + +char *kr_rrset_text(const knot_rrset_t *rr) +{ + if (!rr) { + return NULL; + } + + /* Note: knot_rrset_txt_dump will double the size until the rrset fits */ + size_t bufsize = 128; + char *buf = malloc(bufsize); + int ret = knot_rrset_txt_dump(rr, &buf, &bufsize, &KR_DUMP_STYLE_DEFAULT); + if (ret < 0) { + free(buf); + return NULL; + } + + return buf; +} + +uint64_t kr_now(void) +{ + return uv_now(uv_default_loop()); +} + +void kr_uv_free_cb(uv_handle_t* handle) +{ + free(handle->data); +} + +const char *kr_strptime_diff(const char *format, const char *time1_str, + const char *time0_str, double *diff) { + if (kr_fails_assert(format && time1_str && time0_str && diff)) return NULL; + + struct tm time1_tm; + time_t time1_u; + struct tm time0_tm; + time_t time0_u; + + char *err = strptime(time1_str, format, &time1_tm); + if (err == NULL || err != time1_str + strlen(time1_str)) + return "strptime failed for time1"; + time1_tm.tm_isdst = -1; /* determine if DST is active or not */ + time1_u = mktime(&time1_tm); + if (time1_u == (time_t)-1) + return "mktime failed for time1"; + + err = strptime(time0_str, format, &time0_tm); + if (err == NULL || err != time0_str + strlen(time0_str)) + return "strptime failed for time0"; + time0_tm.tm_isdst = -1; /* determine if DST is active or not */ + time0_u = mktime(&time0_tm); + if (time0_u == (time_t)-1) + return "mktime failed for time0"; + *diff = difftime(time1_u, time0_u); + + return NULL; +} + +int knot_dname_lf2wire(knot_dname_t * const dst, uint8_t len, const uint8_t *lf) +{ + knot_dname_t *d = dst; /* moving "cursor" as we write it out */ + if (kr_fails_assert(d && (len == 0 || lf))) return kr_error(EINVAL); + /* we allow the final zero byte to be omitted */ + if (!len) { + goto finish; + } + if (lf[len - 1]) { + ++len; + } + /* convert the name, one label at a time */ + int label_end = len - 1; /* index of the zero byte after the current label */ + while (label_end >= 0) { + /* find label_start */ + int i = label_end - 1; + while (i >= 0 && lf[i]) + --i; + const int label_start = i + 1; /* index of the first byte of the current label */ + const int label_len = label_end - label_start; + kr_assert(label_len >= 0); + if (label_len > 63 || label_len <= 0) + return kr_error(EILSEQ); + /* write the label */ + *d = label_len; + ++d; + memcpy(d, lf + label_start, label_len); + d += label_len; + /* next label */ + label_end = label_start - 1; + } +finish: + *d = 0; /* the final zero */ + ++d; + return d - dst; +} + +static void rnd_noerror(void *data, uint size) +{ + int ret = gnutls_rnd(GNUTLS_RND_NONCE, data, size); + if (ret) { + kr_log_error(SYSTEM, "gnutls_rnd(): %s\n", gnutls_strerror(ret)); + abort(); + } +} +void kr_rnd_buffered(void *data, uint size) +{ + /* static circular buffer, from index _begin (inclusive) to _end (exclusive) */ + static uint8_t buf[512/8]; /* gnutls_rnd() works on blocks of 512 bits (chacha) */ + static uint buf_begin = sizeof(buf); + + if (unlikely(size > sizeof(buf))) { + rnd_noerror(data, size); + return; + } + /* Start with contiguous chunk, possibly until the end of buffer. */ + const uint size1 = MIN(size, sizeof(buf) - buf_begin); + uint8_t *d = data; + memcpy(d, buf + buf_begin, size1); + if (size1 == size) { + buf_begin += size1; + return; + } + d += size1; + size -= size1; + /* Refill the whole buffer, and finish by another contiguous chunk. */ + rnd_noerror(buf, sizeof(buf)); + memcpy(d, buf, size); + buf_begin = size; +} + +void kr_rrset_init(knot_rrset_t *rrset, knot_dname_t *owner, + uint16_t type, uint16_t rclass, uint32_t ttl) +{ + if (kr_fails_assert(rrset)) return; + knot_rrset_init(rrset, owner, type, rclass, ttl); +} +bool kr_pkt_has_wire(const knot_pkt_t *pkt) +{ + return pkt->size != KR_PKT_SIZE_NOWIRE; +} +bool kr_pkt_has_dnssec(const knot_pkt_t *pkt) +{ + return knot_pkt_has_dnssec(pkt); +} +uint16_t kr_pkt_qclass(const knot_pkt_t *pkt) +{ + return knot_pkt_qclass(pkt); +} +uint16_t kr_pkt_qtype(const knot_pkt_t *pkt) +{ + return knot_pkt_qtype(pkt); +} +uint32_t kr_rrsig_sig_inception(const knot_rdata_t *rdata) +{ + return knot_rrsig_sig_inception(rdata); +} +uint32_t kr_rrsig_sig_expiration(const knot_rdata_t *rdata) +{ + return knot_rrsig_sig_expiration(rdata); +} +uint16_t kr_rrsig_type_covered(const knot_rdata_t *rdata) +{ + return knot_rrsig_type_covered(rdata); +} + +time_t kr_file_mtime (const char* fname) { + struct stat fstat; + + if (stat(fname, &fstat) != 0) { + return 0; + } + + return fstat.st_mtime; +} + +long long kr_fssize(const char *path) +{ + if (!path) + return kr_error(EINVAL); + + struct statvfs buf; + if (statvfs(path, &buf) != 0) + return kr_error(errno); + + return buf.f_frsize * buf.f_blocks; +} + +const char * kr_dirent_name(const struct dirent *de) +{ + return de ? de->d_name : NULL; +} + |