diff --git a/Makefile b/Makefile index 479575d..03c2e3e 100644 --- a/Makefile +++ b/Makefile @@ -3,8 +3,9 @@ # CFLAGS += -Wall -pedantic -std=gnu99 -#CFLAGS += -g -CFLAGS += -O2 -DNDEBUG +CFLAGS += -g +CFLAGS += -O2 +#CFLAGS += -DNDEBUG LDLIBS = -lpthread ifneq ($(CROSS_COMPILE),) @@ -28,11 +29,16 @@ clean: -$(RM) $(BIN) -$(RM) libtinysvcmdns.a -mdns: mdns.o +mdns.o: mdns.h -mdnsd: mdns.o mdnsd.o +mdnsd.o: mdns.h mdnsd.h + +testmdnsd.o: mdnsd.h testmdnsd: testmdnsd.o libtinysvcmdns.a libtinysvcmdns.a: $(patsubst %, libtinysvcmdns.a(%), $(LIBTINYSVCMDNS_OBJS)) +mdnsd: testmdnsd + strip -o $@ $< + diff --git a/mdns.c b/mdns.c index e4a73f5..14912b3 100644 --- a/mdns.c +++ b/mdns.c @@ -40,9 +40,13 @@ #include #endif +/* see RFC 6762 Section 10 */ +#define DEFAULT_TTL_FOR_RECORD_WITH_HOSTNAME 120 +#define DEFAULT_TTL 4500 -#define DEFAULT_TTL 120 - +/* DETECT_CYCLE checks malformed packet you should handle the value carefully */ +/* https://www.kb.cert.org/vuls/id/23495 */ +#define DETECT_CYCLE 255 struct name_comp { uint8_t *label; // label @@ -59,7 +63,7 @@ inline uint8_t *dup_nlabel(const uint8_t *n) { return NULL; assert(n[0] <= 63); // prevent mis-use - return (uint8_t *) strdup((char *) n); + return (uint8_t *)MDNS_STRDUP((char *)n); } // duplicates a label @@ -67,7 +71,7 @@ uint8_t *dup_label(const uint8_t *label) { int len = *label + 1; if (len > 63) return NULL; - uint8_t *newlabel = malloc(len + 1); + uint8_t *newlabel = MDNS_MALLOC(len + 1); strncpy((char *) newlabel, (char *) label, len); newlabel[len] = '\0'; return newlabel; @@ -82,7 +86,7 @@ uint8_t *join_nlabel(const uint8_t *n1, const uint8_t *n2) { len1 = strlen((char *) n1); len2 = strlen((char *) n2); - s = malloc(len1 + len2 + 1); + s = MDNS_MALLOC(len1 + len2 + 1); strncpy((char *) s, (char *) n1, len1); strncpy((char *) s+len1, (char *) n2, len2); s[len1 + len2] = '\0'; @@ -92,15 +96,14 @@ uint8_t *join_nlabel(const uint8_t *n1, const uint8_t *n2) { // returns a human-readable name label in dotted form char *nlabel_to_str(const uint8_t *name) { char *label, *labelp; - const uint8_t *p; size_t buf_len = 256; if (name == NULL) return NULL; - label = labelp = malloc(buf_len); + label = labelp = MDNS_MALLOC(buf_len); - for (p = name; *p; p++) { + for (const uint8_t *p = name; *p; p++) { uint8_t label_len = *p; if (buf_len <= label_len) break; @@ -160,7 +163,7 @@ uint8_t *create_label(const char *txt) { if (len > 63) return NULL; - s = malloc(len + 2); + s = MDNS_MALLOC(len + 2); s[0] = len; strncpy((char *) s + 1, txt, len); s[len + 1] = '\0'; @@ -169,35 +172,29 @@ uint8_t *create_label(const char *txt) { } // creates a uncompressed name label given a DNS name like "apple.b.com" -// free() after use +// MDNS_FREE() after use uint8_t *create_nlabel(const char *name) { char *label; - char *p, *e, *lenpos; int len = 0; assert(name != NULL); len = strlen(name); - label = malloc(len + 1 + 1); + label = MDNS_MALLOC(len + 1 + 1); if (label == NULL) return NULL; strncpy((char *) label + 1, name, len); label[len + 1] = '\0'; - p = label; - e = p + len; - lenpos = p; - - while (p < e) { - *lenpos = 0; + char* p = label; + for (char* e = p + len; p < e; ) { + *p = 0; char *dot = memchr(p + 1, '.', e - p - 1); if (dot == NULL) dot = e + 1; - *lenpos = dot - p - 1; - + *p = dot - p - 1; p = dot; - lenpos = dot; } return (uint8_t *) label; @@ -227,29 +224,43 @@ static uint8_t *uncompress_nlabel(uint8_t *pkt_buf, size_t pkt_len, size_t off) uint8_t *e = pkt_buf + pkt_len; size_t len = 0; char *str, *sp; + uint16_t cycle = 0; if (off >= pkt_len) return NULL; // calculate length of uncompressed label - for (p = pkt_buf + off; *p && p < e; p++) { + for (p = pkt_buf + off; p + 1 < e && *p; p++) { size_t llen = 0; + if (cycle++ >= DETECT_CYCLE) { + DEBUG_PRINTF("malformed packet: DoS (loop in compressed labels)\n"); + return NULL; + } + if ((*p & 0xC0) == 0xC0) { uint8_t *p2 = pkt_buf + (((p[0] & ~0xC0) << 8) | p[1]); + if (p2 >= pkt_buf + pkt_len) { + DEBUG_PRINTF("malformed packet: heap-buffer-overflow (p2 >= pkt_buf+pkt_len)\n"); + return NULL; + } llen = *p2 + 1; p = p2 + llen - 1; } else { llen = *p + 1; p += llen - 1; + if (p + llen > pkt_buf + pkt_len) { + DEBUG_PRINTF("malformed packet: heap-buffer-overflow (p + llen > pkt_buf + pkt_len)\n"); + return NULL; + } } len += llen; } - str = sp = malloc(len + 1); + str = sp = MDNS_MALLOC(len + 1); if (str == NULL) return NULL; // FIXME: must merge this with above code - for (p = pkt_buf + off; *p && p < e; p++) { + for (p = pkt_buf + off; p + 1 < e && *p; p++) { size_t llen = 0; if ((*p & 0xC0) == 0xC0) { uint8_t *p2 = pkt_buf + (((p[0] & ~0xC0) << 8) | p[1]); @@ -291,8 +302,8 @@ void rr_entry_destroy(struct rr_entry *rr) { switch (rr->type) { case RR_PTR: if (rr->data.PTR.name) - free(rr->data.PTR.name); - // don't free entry + MDNS_FREE(rr->data.PTR.name); + // don't free entry break; case RR_TXT: @@ -300,11 +311,11 @@ void rr_entry_destroy(struct rr_entry *rr) { while (txt_rec) { struct rr_data_txt *next = txt_rec->next; if (txt_rec->txt) - free(txt_rec->txt); + MDNS_FREE(txt_rec->txt); // only free() if it wasn't part of the struct if (txt_rec != &rr->data.TXT) - free(txt_rec); + MDNS_FREE(txt_rec); txt_rec = next; } @@ -312,7 +323,12 @@ void rr_entry_destroy(struct rr_entry *rr) { case RR_SRV: if (rr->data.SRV.target) - free(rr->data.SRV.target); + MDNS_FREE(rr->data.SRV.target); + break; + + case RR_AAAA: + if (rr->data.AAAA.addr) + MDNS_FREE(rr->data.AAAA.addr); break; default: @@ -320,8 +336,8 @@ void rr_entry_destroy(struct rr_entry *rr) { break; } - free(rr->name); - free(rr); + MDNS_FREE(rr->name); + MDNS_FREE(rr); } // destroys an RR list (and optionally, items) @@ -332,7 +348,7 @@ void rr_list_destroy(struct rr_list *rr, char destroy_items) { rr_next = rr->next; if (destroy_items) rr_entry_destroy(rr->e); - free(rr); + MDNS_FREE(rr); } } @@ -348,11 +364,11 @@ struct rr_entry *rr_list_remove(struct rr_list **rr_head, struct rr_entry *rr) { if (le->e == rr) { if (pe == NULL) { *rr_head = le->next; - free(le); + MDNS_FREE(le); return rr; } else { pe->next = le->next; - free(le); + MDNS_FREE(le); return rr; } } @@ -377,27 +393,42 @@ int rr_list_append(struct rr_list **rr_head, struct rr_entry *rr) { for (; e; e = e->next) { // already in list - don't add if (e->e == rr) { - free(node); + MDNS_FREE(node); return 0; } if (e->next == NULL) taile = e; } - taile->next = node; + if (taile) + taile->next = node; } return 1; } +#define FILL_QN_ENTRY(rr, _name, _type, _unicast_query) \ + rr->name = _name; \ + rr->type = _type; \ + rr->unicast_query = _unicast_query; \ + rr->rr_class = 1; + #define FILL_RR_ENTRY(rr, _name, _type) \ - rr->name = _name; \ - rr->type = _type; \ - rr->ttl = DEFAULT_TTL; \ - rr->cache_flush = 1; \ - rr->rr_class = 1; + rr->name = _name; \ + rr->type = _type; \ + rr->ttl = DEFAULT_TTL; \ + rr->cache_flush = 1; \ + rr->rr_class = 1; + +struct rr_entry *qn_create(uint8_t *name, enum rr_type type, int unicast_query) +{ + DECL_MALLOC_ZERO_STRUCT(rr, rr_entry); + FILL_QN_ENTRY(rr, name, type, unicast_query); + return rr; +} struct rr_entry *rr_create_a(uint8_t *name, uint32_t addr) { DECL_MALLOC_ZERO_STRUCT(rr, rr_entry); FILL_RR_ENTRY(rr, name, RR_A); + rr->ttl = DEFAULT_TTL_FOR_RECORD_WITH_HOSTNAME; // 120 seconds -- see RFC 6762 Section 10 rr->data.A.addr = addr; return rr; } @@ -405,6 +436,7 @@ struct rr_entry *rr_create_a(uint8_t *name, uint32_t addr) { struct rr_entry *rr_create_aaaa(uint8_t *name, struct in6_addr *addr) { DECL_MALLOC_ZERO_STRUCT(rr, rr_entry); FILL_RR_ENTRY(rr, name, RR_AAAA); + rr->ttl = DEFAULT_TTL_FOR_RECORD_WITH_HOSTNAME; // 120 seconds -- see RFC 6762 Section 10 rr->data.AAAA.addr = addr; return rr; } @@ -414,6 +446,7 @@ struct rr_entry *rr_create_srv(uint8_t *name, uint16_t port, uint8_t *target) { FILL_RR_ENTRY(rr, name, RR_SRV); rr->data.SRV.port = port; rr->data.SRV.target = target; + rr->ttl = DEFAULT_TTL_FOR_RECORD_WITH_HOSTNAME; // 120 seconds -- see RFC 6762 Section 10 return rr; } @@ -422,6 +455,7 @@ struct rr_entry *rr_create_ptr(uint8_t *name, struct rr_entry *d_rr) { FILL_RR_ENTRY(rr, name, RR_PTR); rr->cache_flush = 0; // PTRs shouldn't have their cache flush bit set rr->data.PTR.entry = d_rr; + rr->ttl = DEFAULT_TTL_FOR_RECORD_WITH_HOSTNAME; // 120 seconds -- see RFC 6762 Section 10 return rr; } @@ -431,8 +465,62 @@ struct rr_entry *rr_create(uint8_t *name, enum rr_type type) { return rr; } +struct rr_entry *rr_duplicate(struct rr_entry *rr_src) +{ + if (rr_src == NULL) + return NULL; + + DECL_MALLOC_ZERO_STRUCT(rr, rr_entry); + memcpy(rr, rr_src, sizeof(struct rr_entry)); + if (rr_src->name) + rr->name = dup_nlabel(rr_src->name); + + switch (rr_src->type) { + case RR_PTR: + if (rr_src->data.PTR.name) + rr->data.PTR.name = dup_nlabel(rr_src->data.PTR.name); + break; + + case RR_SRV: + if (rr_src->data.SRV.target) + rr->data.SRV.target = dup_nlabel(rr_src->data.SRV.target); + break; + + case RR_TXT: { + struct rr_data_txt *txt_rec_src = &rr_src->data.TXT;; + struct rr_data_txt *txt_rec = &rr->data.TXT; + if (txt_rec_src->txt) + txt_rec->txt = dup_nlabel(txt_rec_src->txt); + txt_rec_src = txt_rec_src->next; + + while (txt_rec_src) { + txt_rec->next = (struct rr_data_txt *)MDNS_MALLOC(sizeof(struct rr_data_txt)); + memset(txt_rec->next, 0, sizeof(struct rr_data_txt)); + txt_rec = txt_rec->next; + if (txt_rec_src->txt) + txt_rec->txt = dup_nlabel(txt_rec_src->txt); + txt_rec_src = txt_rec_src->next; + } + } + break; + + case RR_AAAA: + if (rr_src->data.AAAA.addr) { + rr->data.AAAA.addr = MDNS_MALLOC(sizeof(struct in6_addr)); + memcpy(rr->data.AAAA.addr, rr_src->data.AAAA.addr, sizeof(struct in6_addr)); + } + break; + + default: + // nothing to allocate memory + break; + } + + return rr; +} + void rr_set_nsec(struct rr_entry *rr_nsec, enum rr_type type) { - assert(rr_nsec->type = RR_NSEC); + assert(rr_nsec->type == RR_NSEC); assert((type / 8) < sizeof(rr_nsec->data.NSEC.bitmap)); rr_nsec->data.NSEC.bitmap[ type / 8 ] = 1 << (7 - (type % 8)); @@ -454,7 +542,7 @@ void rr_add_txt(struct rr_entry *rr_txt, const char *txt) { for (; txt_rec->next; txt_rec = txt_rec->next); // create a new empty node - txt_rec->next = malloc(sizeof(struct rr_data_txt)); + txt_rec->next = MDNS_MALLOC(sizeof(struct rr_data_txt)); txt_rec = txt_rec->next; txt_rec->txt = create_label(txt); @@ -484,6 +572,42 @@ void rr_group_add(struct rr_group **group, struct rr_entry *rr) { *group = g; } +// deletes a record from an rr_group +void rr_group_del(struct rr_group **group, struct rr_entry *rr) +{ + struct rr_group *g; + struct rr_entry *e; + + assert(rr != NULL); + + if (*group) { + g = rr_group_find(*group, rr->name); + if (g) { + e = rr_list_remove(&g->rr, rr); + if (e) { + rr_entry_destroy(e); + } + + if (g->rr == NULL) { + if (*group == g) { + *group = g->next; + } else { + struct rr_group *grp = *group; + for (; grp; grp = grp->next) { + if (grp->next == g) { + grp->next = g->next; + break; + } + } + } + + MDNS_FREE(g->name); + MDNS_FREE(g); + } + } + } +} + // finds a rr_group matching the given name struct rr_group *rr_group_find(struct rr_group* g, uint8_t *name) { for (; g; g = g->next) { @@ -557,6 +681,32 @@ uint32_t mdns_read_u32(const uint8_t *ptr) { ((ptr[3] & 0xFF) << 0); } +// initialize the packet for query +// clears the packet of list structures but not its list items +void mdns_init_query(struct mdns_pkt *pkt, uint16_t id) +{ + // copy transaction ID + pkt->id = id; + + // query flags + pkt->flags = 0; + + rr_list_destroy(pkt->rr_qn, 0); + rr_list_destroy(pkt->rr_ans, 0); + rr_list_destroy(pkt->rr_auth, 0); + rr_list_destroy(pkt->rr_add, 0); + + pkt->rr_qn = NULL; + pkt->rr_ans = NULL; + pkt->rr_auth = NULL; + pkt->rr_add = NULL; + + pkt->num_qn = 0; + pkt->num_ans_rr = 0; + pkt->num_auth_rr = 0; + pkt->num_add_rr = 0; +} + // initialize the packet for reply // clears the packet of list structures but not its list items void mdns_init_reply(struct mdns_pkt *pkt, uint16_t id) { @@ -589,7 +739,7 @@ void mdns_pkt_destroy(struct mdns_pkt *p) { rr_list_destroy(p->rr_auth, 1); rr_list_destroy(p->rr_add, 1); - free(p); + MDNS_FREE(p); } @@ -603,39 +753,51 @@ static size_t mdns_parse_qn(uint8_t *pkt_buf, size_t pkt_len, size_t off, assert(pkt != NULL); - rr = malloc(sizeof(struct rr_entry)); - if (rr == NULL) - goto err; + if (off > pkt_len) { + DEBUG_PRINTF("Offset %zu beyond packet of length %zu\n", off, pkt_len); + return 0; + } + + rr = MDNS_MALLOC(sizeof(struct rr_entry)); + if (rr == NULL) { + DEBUG_PRINTF("Failed to allocate rr_entry\n"); + return 0; + } memset(rr, 0, sizeof(struct rr_entry)); name = uncompress_nlabel(pkt_buf, pkt_len, off); - if (name == NULL) - goto err; + if (!name) { + DEBUG_PRINTF("malformed packet bad name\n"); + MDNS_FREE(rr); + return 0; + } p += label_len(pkt_buf, pkt_len, off); rr->name = name; + if (p + 4 > pkt_buf + pkt_len) { + DEBUG_PRINTF("malformed packet buff overflow\n"); + MDNS_FREE(rr); + MDNS_FREE(name); + return 0; + } rr->type = mdns_read_u16(p); p += sizeof(uint16_t); rr->unicast_query = (*p & 0x80) == 0x80; - rr->rr_class = mdns_read_u16(p) & ~0x80; + rr->rr_class = mdns_read_u16(p) & ~0x8000; p += sizeof(uint16_t); rr_list_append(&pkt->rr_qn, rr); return p - (pkt_buf + off); - -err: - free(rr); - return 0; } // parse the MDNS RR section // stores the parsed data in the given mdns_pkt struct static size_t mdns_parse_rr(uint8_t *pkt_buf, size_t pkt_len, size_t off, - struct mdns_pkt *pkt) { + struct mdns_pkt *pkt, struct rr_list **rr_l) { const uint8_t *p = pkt_buf + off; const uint8_t *e = pkt_buf + pkt_len; struct rr_entry *rr; @@ -649,24 +811,35 @@ static size_t mdns_parse_rr(uint8_t *pkt_buf, size_t pkt_len, size_t off, if (off > pkt_len) return 0; - rr = malloc(sizeof(struct rr_entry)); - if (rr == NULL) - goto err; + rr = MDNS_MALLOC(sizeof(struct rr_entry)); memset(rr, 0, sizeof(struct rr_entry)); + if (rr == NULL) { + DEBUG_PRINTF("Failed to allocate rr_entry\n"); + return 0; + } name = uncompress_nlabel(pkt_buf, pkt_len, off); - if (name == NULL) - goto err; + if (!name) { + DEBUG_PRINTF("malformed packet bad name\n"); + MDNS_FREE(rr); + return 0; + } p += label_len(pkt_buf, pkt_len, off); rr->name = name; + if (p + 10 - pkt_buf > pkt_len) { + DEBUG_PRINTF("malformed packet buff overflow\n"); + MDNS_FREE(rr); + MDNS_FREE(name); + return 0; + } rr->type = mdns_read_u16(p); p += sizeof(uint16_t); rr->cache_flush = (*p & 0x80) == 0x80; - rr->rr_class = mdns_read_u16(p) & ~0x80; + rr->rr_class = mdns_read_u16(p) & ~0x8000; p += sizeof(uint16_t); rr->ttl = mdns_read_u32(p); @@ -677,7 +850,7 @@ static size_t mdns_parse_rr(uint8_t *pkt_buf, size_t pkt_len, size_t off, p += sizeof(uint16_t); if (p + rr_data_len > e) { - DEBUG_PRINTF("rr_data_len goes beyond packet buffer: %lu > %lu\n", rr_data_len, e - p); + DEBUG_PRINTF("rr_data_len goes beyond packet buffer: %zu > %zu\n", rr_data_len, e - p); rr_entry_destroy(rr); return 0; } @@ -688,7 +861,7 @@ static size_t mdns_parse_rr(uint8_t *pkt_buf, size_t pkt_len, size_t off, switch (rr->type) { case RR_A: if (rr_data_len < sizeof(uint32_t)) { - DEBUG_PRINTF("invalid rr_data_len=%lu for A record\n", rr_data_len); + DEBUG_PRINTF("invalid rr_data_len=%zu for A record\n", rr_data_len); parse_error = 1; break; } @@ -698,11 +871,11 @@ static size_t mdns_parse_rr(uint8_t *pkt_buf, size_t pkt_len, size_t off, case RR_AAAA: if (rr_data_len < sizeof(struct in6_addr)) { - DEBUG_PRINTF("invalid rr_data_len=%lu for AAAA record\n", rr_data_len); + DEBUG_PRINTF("invalid rr_data_len=%zu for AAAA record\n", rr_data_len); parse_error = 1; break; } - rr->data.AAAA.addr = malloc(sizeof(struct in6_addr)); + rr->data.AAAA.addr = MDNS_MALLOC(sizeof(struct in6_addr)); for (int i = 0; i < sizeof(struct in6_addr); i++) rr->data.AAAA.addr->s6_addr[i] = p[i]; p += sizeof(struct in6_addr); @@ -718,6 +891,25 @@ static size_t mdns_parse_rr(uint8_t *pkt_buf, size_t pkt_len, size_t off, p += rr_data_len; break; + case RR_SRV: + rr->data.SRV.priority = mdns_read_u16(p); + p += sizeof(uint16_t); + + rr->data.SRV.weight = mdns_read_u16(p); + p += sizeof(uint16_t); + + rr->data.SRV.port = mdns_read_u16(p); + p += sizeof(uint16_t); + + rr->data.SRV.target = uncompress_nlabel(pkt_buf, pkt_len, p - pkt_buf); + if (rr->data.SRV.target == NULL) { + DEBUG_PRINTF("unable to parse/uncompress label for SRV target\n"); + parse_error = 1; + break; + } + p += (rr_data_len - (3 * sizeof(uint16_t))); + break; + case RR_TXT: txt_rec = &rr->data.TXT; @@ -741,7 +933,7 @@ static size_t mdns_parse_rr(uint8_t *pkt_buf, size_t pkt_len, size_t off, break; // allocate another record - txt_rec->next = malloc(sizeof(struct rr_data_txt)); + txt_rec->next = MDNS_MALLOC(sizeof(struct rr_data_txt)); txt_rec = txt_rec->next; txt_rec->next = NULL; } @@ -751,6 +943,8 @@ static size_t mdns_parse_rr(uint8_t *pkt_buf, size_t pkt_len, size_t off, // skip to end of RR data p = e; } + // update time + rr->update_time = time(NULL); // if there was a parse error, destroy partial rr_entry if (parse_error) { @@ -758,24 +952,21 @@ static size_t mdns_parse_rr(uint8_t *pkt_buf, size_t pkt_len, size_t off, return 0; } - rr_list_append(&pkt->rr_ans, rr); + rr_list_append(rr_l, rr); return p - (pkt_buf + off); -err: - free(rr); - return 0; } // parse a MDNS packet into an mdns_pkt struct struct mdns_pkt *mdns_parse_pkt(uint8_t *pkt_buf, size_t pkt_len) { uint8_t *p = pkt_buf; - size_t off; struct mdns_pkt *pkt; - int i; - if (pkt_len < 12) + if (pkt_len < 12) { + DEBUG_PRINTF("malformed packet: pkt size is less than mininum mdns packet\n"); return NULL; + } MALLOC_ZERO_STRUCT(pkt, mdns_pkt); @@ -787,35 +978,56 @@ struct mdns_pkt *mdns_parse_pkt(uint8_t *pkt_buf, size_t pkt_len) { pkt->num_auth_rr = mdns_read_u16(p); p += sizeof(uint16_t); pkt->num_add_rr = mdns_read_u16(p); p += sizeof(uint16_t); - off = p - pkt_buf; + size_t off = p - pkt_buf; // parse questions - for (i = 0; i < pkt->num_qn; i++) { + for (int i = 0; i < pkt->num_qn; i++) { size_t l = mdns_parse_qn(pkt_buf, pkt_len, off, pkt); if (! l) { DEBUG_PRINTF("error parsing question #%d\n", i); - mdns_pkt_destroy(pkt); - return NULL; + goto error_with_parsing; } off += l; } // parse answer RRs - for (i = 0; i < pkt->num_ans_rr; i++) { - size_t l = mdns_parse_rr(pkt_buf, pkt_len, off, pkt); - if (! l) { + for (int i = 0; i < pkt->num_ans_rr; i++) { + size_t l = mdns_parse_rr(pkt_buf, pkt_len, off, pkt, &pkt->rr_ans); + if (!l) { DEBUG_PRINTF("error parsing answer #%d\n", i); - mdns_pkt_destroy(pkt); - return NULL; + goto error_with_parsing; } off += l; } - // TODO: parse the authority and additional RR sections + // parse authority RRs + for (int i = 0; i < pkt->num_auth_rr; i++) { + size_t l = mdns_parse_rr(pkt_buf, pkt_len, off, pkt, &pkt->rr_auth); + if (!l) { + DEBUG_PRINTF("error parsing authority rr #%d\n", i); + goto error_with_parsing; + } + off += l; + } + + // parse additional RRs + for (int i = 0; i < pkt->num_add_rr; i++) { + size_t l = mdns_parse_rr(pkt_buf, pkt_len, off, pkt, &pkt->rr_add); + if (!l) { + DEBUG_PRINTF("error parsing additional rr #%d\n", i); + goto error_with_parsing; + } + + off += l; + } return pkt; + +error_with_parsing: + mdns_pkt_destroy(pkt); + return NULL; } // encodes a name (label) into a packet using the name compression scheme @@ -848,7 +1060,8 @@ static size_t mdns_encode_name(uint8_t *pkt_buf, size_t pkt_len, size_t off, new_c->label = (uint8_t *) name; new_c->pos = p - pkt_buf; - c_tail->next = new_c; + if (c_tail) + c_tail->next = new_c; // advance to next name segment p += segment_len; @@ -863,6 +1076,29 @@ static size_t mdns_encode_name(uint8_t *pkt_buf, size_t pkt_len, size_t off, return len; } +// encode a QN entry at the given offset +// returns the size of the QN entry +static size_t mdns_encode_qn(uint8_t *pkt_buf, size_t pkt_len, size_t off, struct rr_entry *rr, struct name_comp *comp) +{ + uint8_t *p = pkt_buf + off; + size_t l; + + assert(off < pkt_len); + + // name + l = mdns_encode_name(pkt_buf, pkt_len, off, rr->name, comp); + assert(l != 0); + p += l; + + // type + p = mdns_write_u16(p, rr->type); + + // class & unicast query + p = mdns_write_u16(p, (rr->rr_class & ~0x8000) | (rr->unicast_query << 15)); + + return p - pkt_buf - off; +} + // encodes an RR entry at the given offset // returns the size of the entire RR entry static size_t mdns_encode_rr(uint8_t *pkt_buf, size_t pkt_len, size_t off, @@ -908,8 +1144,8 @@ static size_t mdns_encode_rr(uint8_t *pkt_buf, size_t pkt_len, size_t off, case RR_PTR: label = rr->data.PTR.name ? - rr->data.PTR.name : - rr->data.PTR.entry->name; + rr->data.PTR.name : + rr->data.PTR.entry->name; p += mdns_encode_name(pkt_buf, pkt_len, p - pkt_buf, label, comp); break; @@ -961,28 +1197,30 @@ static size_t mdns_encode_rr(uint8_t *pkt_buf, size_t pkt_len, size_t off, // encodes a MDNS packet from the given mdns_pkt struct into a buffer // returns the size of the entire MDNS packet -size_t mdns_encode_pkt(struct mdns_pkt *answer, uint8_t *pkt_buf, size_t pkt_len) { +size_t mdns_encode_pkt(struct mdns_pkt *encoded_pkt, uint8_t *pkt_buf, size_t pkt_len) { struct name_comp *comp; uint8_t *p = pkt_buf; - //uint8_t *e = pkt_buf + pkt_len; size_t off; - int i; - - assert(answer != NULL); + struct rr_list *rr; + int result; + + assert(encoded_pkt != NULL); assert(pkt_len >= 12); if (p == NULL) return -1; +#if 0 /* disabled - now it *can* have qns */ // this is an Answer - number of qns should be zero assert(answer->num_qn == 0); +#endif - p = mdns_write_u16(p, answer->id); - p = mdns_write_u16(p, answer->flags); - p = mdns_write_u16(p, answer->num_qn); - p = mdns_write_u16(p, answer->num_ans_rr); - p = mdns_write_u16(p, answer->num_auth_rr); - p = mdns_write_u16(p, answer->num_add_rr); + p = mdns_write_u16(p, encoded_pkt->id); + p = mdns_write_u16(p, encoded_pkt->flags); + p = mdns_write_u16(p, encoded_pkt->num_qn); + p = mdns_write_u16(p, encoded_pkt->num_ans_rr); + p = mdns_write_u16(p, encoded_pkt->num_auth_rr); + p = mdns_write_u16(p, encoded_pkt->num_add_rr); off = p - pkt_buf; @@ -996,36 +1234,178 @@ size_t mdns_encode_pkt(struct mdns_pkt *answer, uint8_t *pkt_buf, size_t pkt_len comp->label = (uint8_t *) ""; comp->pos = 0; - // skip encoding of qn + // encode of qn + for (rr = encoded_pkt->rr_qn; rr; rr = rr->next) { + size_t l = mdns_encode_qn(pkt_buf, pkt_len, off, rr->e, comp); + off += l; + + if (off >= pkt_len) { + DEBUG_PRINTF("packet buffer too small\n"); + goto done; + } + } struct rr_list *rr_set[] = { - answer->rr_ans, - answer->rr_auth, - answer->rr_add + encoded_pkt->rr_ans, + encoded_pkt->rr_auth, + encoded_pkt->rr_add }; // encode answer, authority and additional RRs - for (i = 0; i < sizeof(rr_set) / sizeof(rr_set[0]); i++) { - struct rr_list *rr = rr_set[i]; - for (; rr; rr = rr->next) { + for (int i = 0; i < sizeof(rr_set) / sizeof(rr_set[0]); i++) { + for (rr = rr_set[i]; rr; rr = rr->next) { size_t l = mdns_encode_rr(pkt_buf, pkt_len, off, rr->e, comp); off += l; if (off >= pkt_len) { DEBUG_PRINTF("packet buffer too small\n"); - return -1; + goto done; } } } + /* result is success */ + result = 0; + +done: // free name compression list while (comp) { struct name_comp *c = comp->next; - free(comp); + MDNS_FREE(comp); comp = c; } + if (result != 0) + return -1; + return off; } +#if (MDNS_DEBUG_PRINTF == 1) && (MDNS_MEMORY_DEBUG == 1) +struct mdns_meminfo_node { + char *func; + int line; + void *addr; + unsigned int size; + struct mdns_meminfo_node *next; +}; + +static struct mdns_meminfo_node *g_mdns_meminfo_head = NULL; + +static void add_meminfo_node(const char *func, int line, void *addr, unsigned int size) +{ + struct mdns_meminfo_node *new_node = (struct mdns_meminfo_node *)malloc(sizeof(struct mdns_meminfo_node)); + if (new_node == NULL) { + DEBUG_PRINTF("ERROR: cannot allocate memory for mdns_meminfo_node\n"); + return; + } + + new_node->func = strdup(func); + new_node->line = line; + new_node->addr = addr; + new_node->size = size; + new_node->next = NULL; + + if (g_mdns_meminfo_head) { + struct mdns_meminfo_node *pnode = g_mdns_meminfo_head; + while (pnode->next) { + pnode = pnode->next; + } + + pnode->next = new_node; + } else { + g_mdns_meminfo_head = new_node; + } +} + +static void remove_meminfo_node(const char *func, int line, void *addr) +{ + int b_found = 0; + struct mdns_meminfo_node *cur_node = g_mdns_meminfo_head; + struct mdns_meminfo_node *prev_node = NULL; + + while (cur_node) { + if (cur_node->addr == addr) { + b_found = 1; + break; + } + + prev_node = cur_node; + cur_node = cur_node->next; + } + + if (b_found) { + if (cur_node == g_mdns_meminfo_head) { + g_mdns_meminfo_head = cur_node->next; + } else { + prev_node->next = cur_node->next; + } + + free(cur_node->func); + free(cur_node); + } else { + DEBUG_PRINTF("Something Wrong!!! There is no address to remove. (address=%p, %s(%d))\n", addr, func, line); + } +} + +void *mdns_malloc(const char *func_name, int line, unsigned int size) +{ + void *ptr = malloc(size); + if (ptr) { + add_meminfo_node(func_name, line, ptr, size); + } else { + DEBUG_PRINTF("ERROR: cannot allocate memory (size=%d, %s(%d))\n", size, func_name, line); + } + + return ptr; +} + +void mdns_free(const char *func_name, int line, void *ptr) +{ + if (ptr) { + remove_meminfo_node(func_name, line, ptr); + free(ptr); + } else { + DEBUG_PRINTF("ERROR: cannot release memory (ptr=%p, %s(%d))\n", ptr, func_name, line); + } +} + +char *mdns_strdup(const char *func_name, int line, const char *str) +{ + char *ptr = strdup(str); + int size = strlen(str) + 1; + if (ptr) { + add_meminfo_node(func_name, line, ptr, size); + } else { + DEBUG_PRINTF("ERROR: cannot allocate string buffer memory (size=%d, %s(%d))\n", size, func_name, line); + } + + return ptr; +} + +void mdns_show_meminfo(void) +{ + DEBUG_PRINTF("===========================================================\n"); + DEBUG_PRINTF(" MDNS Memory Information\n"); + DEBUG_PRINTF("===========================================================\n"); + if (g_mdns_meminfo_head) { + int total_size = 0; + struct mdns_meminfo_node *cur_node = g_mdns_meminfo_head; + while (cur_node) { + DEBUG_PRINTF(" [address=0x%08X] [size=%d] %s(%d)\n", (int)cur_node->addr, cur_node->size, cur_node->func, cur_node->line); + total_size += cur_node->size; + cur_node = cur_node->next; + } + + DEBUG_PRINTF("\n"); + DEBUG_PRINTF(" TOTAL SIZE = %d\n", total_size); + } + + else { + DEBUG_PRINTF(" There is Nothing...\n"); + } + DEBUG_PRINTF("===========================================================\n\n"); +} + +#endif /* MDNS_DEBUG_PRINTF==1 && MDNS_MEMORY_DEBUG==1 */ diff --git a/mdns.h b/mdns.h index e56fc2a..79b44c8 100644 --- a/mdns.h +++ b/mdns.h @@ -32,6 +32,7 @@ #include #include #include +#include #ifdef _WIN32 #include @@ -39,14 +40,42 @@ #include #endif +#ifndef MDNS_DEBUG_PRINTF +#define MDNS_DEBUG_PRINTF 0 +#endif + +#if MDNS_DEBUG_PRINTF==1 +#define MDNS_RR_DEBUG 0 +#define MDNS_MEMORY_DEBUG 0 +#endif + +#if MDNS_DEBUG_PRINTF==1 && MDNS_MEMORY_DEBUG==1 +void *mdns_malloc(const char *func_name, int line, unsigned int size); +void mdns_free(const char *func_name, int line, void *ptr); +char *mdns_strdup(const char *func_name, int line, const char *str); +void mdns_show_meminfo(void); + +#define MDNS_MALLOC(size) mdns_malloc(__FUNCTION__, __LINE__, size) +#define MDNS_FREE(ptr) mdns_free(__FUNCTION__, __LINE__, ptr) +#define MDNS_STRDUP(str) mdns_strdup(__FUNCTION__, __LINE__, str) + +#else +#define MDNS_MALLOC(size) malloc(size) +#define MDNS_FREE(ptr) free(ptr) +#define MDNS_STRDUP(size) strdup(size) +#endif #define MALLOC_ZERO_STRUCT(x, type) \ - x = malloc(sizeof(struct type)); \ - memset(x, 0, sizeof(struct type)); + x = MDNS_MALLOC(sizeof(struct type)); \ + memset(x, 0, sizeof(struct type)) #define DECL_MALLOC_ZERO_STRUCT(x, type) \ struct type * MALLOC_ZERO_STRUCT(x, type) -#ifndef NDEBUG +#define DECL_ZERO_STRUCT(_x, _type) \ + struct _type _x; \ + memset(&(_x), 0, sizeof(struct _type)) + +#if MDNS_DEBUG_PRINTF==1 #define DEBUG_PRINTF(...) printf(__VA_ARGS__) #else #define DEBUG_PRINTF(...) ((void) 0) @@ -118,6 +147,7 @@ struct rr_entry { struct rr_data_a A; struct rr_data_aaaa AAAA; } data; + time_t update_time; }; struct rr_list { @@ -162,8 +192,9 @@ struct mdns_pkt { struct mdns_pkt *mdns_parse_pkt(uint8_t *pkt_buf, size_t pkt_len); +void mdns_init_query(struct mdns_pkt *pkt, uint16_t id); void mdns_init_reply(struct mdns_pkt *pkt, uint16_t id); -size_t mdns_encode_pkt(struct mdns_pkt *answer, uint8_t *pkt_buf, size_t pkt_len); +size_t mdns_encode_pkt(struct mdns_pkt *encoded_pkt, uint8_t *pkt_buf, size_t pkt_len); void mdns_pkt_destroy(struct mdns_pkt *p); void rr_group_destroy(struct rr_group *group); @@ -171,17 +202,20 @@ struct rr_group *rr_group_find(struct rr_group *g, uint8_t *name); struct rr_entry *rr_entry_find(struct rr_list *rr_list, uint8_t *name, uint16_t type); struct rr_entry *rr_entry_match(struct rr_list *rr_list, struct rr_entry *entry); void rr_group_add(struct rr_group **group, struct rr_entry *rr); +void rr_group_del(struct rr_group **group, struct rr_entry *rr); int rr_list_count(struct rr_list *rr); int rr_list_append(struct rr_list **rr_head, struct rr_entry *rr); struct rr_entry *rr_list_remove(struct rr_list **rr_head, struct rr_entry *rr); void rr_list_destroy(struct rr_list *rr, char destroy_items); +struct rr_entry *qn_create(uint8_t *name, enum rr_type type, int unicast_query); struct rr_entry *rr_create_ptr(uint8_t *name, struct rr_entry *d_rr); struct rr_entry *rr_create_srv(uint8_t *name, uint16_t port, uint8_t *target); struct rr_entry *rr_create_aaaa(uint8_t *name, struct in6_addr *addr); struct rr_entry *rr_create_a(uint8_t *name, uint32_t addr); struct rr_entry *rr_create(uint8_t *name, enum rr_type type); +struct rr_entry *rr_duplicate(struct rr_entry *rr_src); void rr_set_nsec(struct rr_entry *rr_nsec, enum rr_type type); void rr_add_txt(struct rr_entry *rr_txt, const char *txt); diff --git a/mdnsd.c b/mdnsd.c index 6488a53..bfde20a 100644 --- a/mdnsd.c +++ b/mdnsd.c @@ -26,6 +26,8 @@ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ +/* mdns core and API */ + #ifdef _WIN32 #include #include @@ -51,6 +53,14 @@ #include #include #include +#include +//#include +#ifndef NSEC_PER_SEC +#define NSEC_PER_SEC (1000000000L) +#endif +#include +#include +#define get_errno() (errno) /* * Define a proper IP socket level if not already done. @@ -63,33 +73,95 @@ #include "mdns.h" #include "mdnsd.h" +#if (MDNS_DEBUG_PRINTF == 1) && (MDNS_RR_DEBUG == 1) +#define MDNSD_RR_DEBUG +#endif + +#if (MDNS_DEBUG_PRINTF == 1) && (MDNS_MEMORY_DEBUG == 1) +#define MDNSD_MEMORY_DEBUG +#endif + +#define THREAD_MAINLOOP_NAME "MDNS" +#define THREAD_MAINLOOP_STACKSIZE 4096 + +#define PIPE_SOCKET_TYPE 0 +#define PIPE_SOCKET_PORT0 65353 +#define PIPE_SOCKET_PORT1 65354 + #define MDNS_ADDR "224.0.0.251" #define MDNS_PORT 5353 -#define PACKET_SIZE 65536 +#define MDNS_SUFFIX_LOCAL ".local" +#define MDNS_SUFFIX_SITE ".site" +#define MDNS_CHECK_SUBTYPE_STR "._sub." + +#define PACKET_SIZE 1536 /* maximum packet size : */ +//#define PACKET_SIZE 65536 #define SERVICES_DNS_SD_NLABEL \ ((uint8_t *) "\x09_services\x07_dns-sd\x04_udp\x05local") +#define TIME_GET(time) gettimeofday(&time, NULL) +#define TIME_DIFF_USEC(old_time, cur_time) \ + ((cur_time.tv_sec * 1000000 + cur_time.tv_usec) - (old_time.tv_sec * 1000000 + old_time.tv_usec)) + +#define MAX_ECONNRESET_COUNT 5 + +enum mdns_cache_status { + CACHE_SLEEP = 0, + CACHE_NORMAL = 1, + CACHE_RESOLVE_HOSTNAME = 2, + CACHE_SERVICE_DISCOVERY = 3, +}; + +enum mdns_domain { + MDNS_DOMAIN_UNKNOWN = 0, + MDNS_DOMAIN_LOCAL = 1, +#if defined(CONFIG_NETUTILS_MDNS_XMDNS) + MDNS_DOMAIN_SITE = 2, +#endif +}; + struct mdnsd { pthread_mutex_t data_lock; + sem_t sendmsg_sem; int sockfd; int notify_pipe[2]; int stop_flag; + int sendmsg_requested; + int domain; + enum mdns_cache_status c_status; + char *c_filter; + struct rr_group *cache; + struct rr_list *query; +#ifndef MDNS_NO_RESPONDER_SUPPORT struct rr_group *group; struct rr_list *announce; struct rr_list *services; - uint8_t *hostname; + struct rr_list *probe; + uint8_t *hostname; /* hostname can be changed if name collision occur */ + uint8_t *hostname_org; +#endif }; +#ifndef MDNS_NO_RESPONDER_SUPPORT struct mdns_service { struct rr_list *entries; }; +#endif + +static void update_cache(struct mdnsd *svr); +static void clear_service_discovery_result(struct mdns_service_info + *service_list, int num_of_services); +static void release_mdns_context_resource(void); + +static struct mdnsd *g_svr = NULL; +static struct mdns_service_info *g_service_list = NULL; +static pthread_mutex_t g_cmd_lock; +static int g_cmd_lock_initialized = 0; ///////////////////////////////// - - static void log_message(int loglevel, char *fmt_str, ...) { va_list ap; char buf[2048]; @@ -102,51 +174,395 @@ static void log_message(int loglevel, char *fmt_str, ...) { fprintf(stderr, "%s\n", buf); } -static int create_recv_sock() { +#ifdef MDNSD_RR_DEBUG +static void print_rr_entry(struct rr_entry *rr_e) +{ + char *str1, *str2; + + if (!rr_e) { + DEBUG_PRINTF("ERROR: No RR Entry\n"); + return; + } + + if (rr_e->name) { + str1 = nlabel_to_str(rr_e->name); + } else { + str1 = NULL; + } + + if ((rr_e->type == RR_PTR) && rr_e->data.PTR.name) { + str2 = nlabel_to_str(rr_e->data.PTR.name); + } else if ((rr_e->type == RR_SRV) && rr_e->data.SRV.target) { + str2 = nlabel_to_str(rr_e->data.SRV.target); + } else { + str2 = NULL; + } + + DEBUG_PRINTF("type:%s, ttl=%d, time=%d, ca_fl=%d, rr_class=%d, name=[%s]", rr_get_type_name(rr_e->type), rr_e->ttl, (unsigned int)(time(NULL) - rr_e->update_time), (int)rr_e->cache_flush, rr_e->rr_class, str1 ? str1 : "NULL"); + + if (rr_e->type == RR_SRV || rr_e->type == RR_PTR) { + DEBUG_PRINTF(", target=[%s]\n", str2 ? str2 : "NULL"); + } else { + DEBUG_PRINTF("\n"); + } + + if (str1) { + MDNS_FREE(str1); + } + if (str2) { + MDNS_FREE(str2); + } +} + +static void print_cache(struct mdnsd *svr) +{ + struct rr_group *group = svr->cache; + struct rr_list *list = NULL; + struct rr_entry *entry = NULL; + char *pname = NULL; + + DEBUG_PRINTF("\n"); + DEBUG_PRINTF(" Multicast DNS Cache\n"); + + for (; group; group = group->next) { + if (group->name) { + pname = nlabel_to_str(group->name); + } else { + pname = NULL; + } + + DEBUG_PRINTF("==================================================\n"); + DEBUG_PRINTF(" Group: %s\n", pname ? pname : "Unknown"); + DEBUG_PRINTF("==================================================\n"); + if (pname) { + MDNS_FREE(pname); + } + + list = group->rr; + for (; list; list = list->next) { + entry = list->e; + if (entry) { + print_rr_entry(entry); + } + } + } + DEBUG_PRINTF("==================================================\n"); + DEBUG_PRINTF("\n"); +} +#endif /* MDNSD_RR_DEBUG */ + +static int check_mdns_domain(const char *name) +{ + char *str = NULL; + int domain = MDNS_DOMAIN_UNKNOWN; + + if (name == NULL) { + goto done; + } +#if defined(CONFIG_NETUTILS_MDNS_XMDNS) + str = strstr(name, MDNS_SUFFIX_SITE); + if (str && strcmp(str, MDNS_SUFFIX_SITE) == 0) { + domain = MDNS_DOMAIN_SITE; + goto done; + } +#endif + + str = strstr(name, MDNS_SUFFIX_LOCAL); + if (str && strcmp(str, MDNS_SUFFIX_LOCAL) == 0) { + domain = MDNS_DOMAIN_LOCAL; + goto done; + } + + domain = MDNS_DOMAIN_UNKNOWN; + +done: + return domain; +} + +static char *get_service_type_without_subtype(char *name) +{ + char *str = NULL; + + str = strstr(name, MDNS_CHECK_SUBTYPE_STR); + if (str) { + str += strlen(MDNS_CHECK_SUBTYPE_STR); + } else { + str = name; + } + + return str; +} + +#ifndef MDNS__NO_RESPONDER_SUPPORT +static int lookup_hostname(struct mdnsd *svr, char *hostname) +{ + int result = -1; + struct rr_group *group = svr->cache; + struct rr_list *list = NULL; + struct rr_entry *entry = NULL; + int b_found = 0; + char *e_name; + int ret; + + pthread_mutex_lock(&svr->data_lock); + + for (; group; group = group->next) { + list = group->rr; + for (; list; list = list->next) { + entry = list->e; + if (entry && entry->name) { + e_name = nlabel_to_str(entry->name); + ret = strncmp(e_name, hostname, strlen(hostname)); + MDNS_FREE(e_name); + } else { + ret = -1; + } + + if (ret == 0) { + b_found = 1; + break; + } + } + + if (b_found) { + break; + } + } + + pthread_mutex_unlock(&svr->data_lock); + + if (b_found) { + result = 0; + } + + return result; +} +#endif /* !defined MDNS_NO_RESPONDER_SUPPORT */ + +static int lookup_hostname_to_addr(struct mdnsd *svr, char *hostname, int *ipaddr) +{ + int result = -1; + struct rr_group *group = svr->cache; + struct rr_list *list = NULL; + struct rr_entry *entry = NULL; + int b_found = 0; + char *e_name; + int ret; + + update_cache(svr); + + pthread_mutex_lock(&svr->data_lock); + + for (; group; group = group->next) { + list = group->rr; + for (; list; list = list->next) { + entry = list->e; + if (entry && (entry->type == RR_A)) { // currently, support only ipv4 + if (entry->name) { + e_name = nlabel_to_str(entry->name); + ret = strncmp(e_name, hostname, strlen(hostname)); + MDNS_FREE(e_name); + } else { + ret = -1; + } + + if (ret == 0) { + *ipaddr = entry->data.A.addr; + b_found = 1; + break; + } + } + } + + if (b_found) { + break; + } + } + + pthread_mutex_unlock(&svr->data_lock); + + if (b_found) { + result = 0; + } + + return result; +} + +static int lookup_service(struct mdnsd *svr, char *type, struct mdns_service_info *service_list, int *num_of_services) +{ + int result = -1; + int result_cnt = 0; + uint8_t *type_nlabel = create_nlabel(type); + char *type_without_subtype = get_service_type_without_subtype(type); + + clear_service_discovery_result(service_list, MAX_NUMBER_OF_SERVICE_DISCOVERY_RESULT); + + update_cache(svr); + + pthread_mutex_lock(&svr->data_lock); + + struct rr_group *ptr_grp = rr_group_find(svr->cache, (uint8_t *)type_nlabel); + + MDNS_FREE(type_nlabel); + if (ptr_grp) { + struct rr_list *list = ptr_grp->rr; + struct rr_entry *entry = NULL; + for (; list; list = list->next) { + entry = list->e; + if (entry && (entry->type == RR_PTR)) { + if (entry->data.PTR.name) { /* SRV's name */ + struct rr_group *srv_grp = rr_group_find(svr->cache, + (uint8_t *)entry->data.PTR.name); + if (srv_grp) { + /* find service */ + struct rr_entry *srv_e = rr_entry_find(srv_grp->rr, entry->data.PTR.name, + RR_SRV); + if (srv_e && srv_e->name) { + char *name = nlabel_to_str(srv_e->name); /* full service name */ + char *ptr = strstr(name, + type_without_subtype); /* separate instance name and service type */ + + if (ptr && (ptr > name)) { + *(ptr - 1) = '\0'; + } else { + MDNS_FREE(name); + continue; + } + + /* set instance name */ + service_list[result_cnt].instance_name = MDNS_STRDUP(name); + /* set service type */ + service_list[result_cnt].type = MDNS_STRDUP(ptr); + + MDNS_FREE(name); + + /* set hostname */ + if (srv_e->data.SRV.target) { + struct rr_group *a_grp = NULL; + name = nlabel_to_str(srv_e->data.SRV.target); + name[strlen(name) - 1] = '\0'; + service_list[result_cnt].hostname = MDNS_STRDUP(name); + MDNS_FREE(name); + + /* ip address */ + a_grp = rr_group_find(svr->cache, (uint8_t *)srv_e->data.SRV.target); + if (a_grp) { + struct rr_entry *a_e = rr_entry_find(a_grp->rr, srv_e->data.SRV.target, RR_A); + if (a_e) { + service_list[result_cnt].ipaddr = a_e->data.A.addr; + } + } + + } + + /* port */ + service_list[result_cnt].port = srv_e->data.SRV.port; + + result_cnt++; /* increase result count */ + + if (result_cnt >= MAX_NUMBER_OF_SERVICE_DISCOVERY_RESULT) { + break; + } + + } + + } + + } + } + } + } + + pthread_mutex_unlock(&svr->data_lock); + + *num_of_services = result_cnt; + + if (*num_of_services > 0) { + result = 0; + } + + return result; +} + +static int create_recv_sock(int domain) +{ + char *addr; + int port; + int r; + + switch (domain) { +#if defined(CONFIG_NETUTILS_MDNS_XMDNS) + case MDNS_DOMAIN_SITE: + addr = CONFIG_NETUTILS_MDNS_XMDNS_MULTICAST_ADDR; + port = CONFIG_NETUTILS_MDNS_XMDNS_PORT_NUM; + break; +#endif + case MDNS_DOMAIN_LOCAL: + default: + addr = MDNS_ADDR; + port = MDNS_PORT; + break; + } + int sd = socket(AF_INET, SOCK_DGRAM, 0); if (sd < 0) { - log_message(LOG_ERR, "recv socket(): %m"); + log_message(LOG_ERR, "recv socket(): %s\n", strerror(errno)); return sd; } - int r = -1; - int on = 1; if ((r = setsockopt(sd, SOL_SOCKET, SO_REUSEADDR, (char *) &on, sizeof(on))) < 0) { - log_message(LOG_ERR, "recv setsockopt(SO_REUSEADDR): %m"); + close(sd); + log_message(LOG_ERR, "recv setsockopt(SO_REUSEADDR): %s\n", strerror(errno)); return r; } +#if !defined(WIN32) && defined(SO_REUSEPORT) + if (!getsockopt(sd, SOL_SOCKET, SO_REUSEPORT,(char*) &on, &addrlen)) { + if ((r = setsockopt(sd, SOL_SOCKET, SO_REUSEPORT,(char*) &on, sizeof(on))) < 0) { + log_message(LOG_ERR, "recv setsockopt(SO_REUSEPORT): %d; %s\n", r, strerror(errno)); + } + } +#endif + + /* bind to an address */ - struct sockaddr_in serveraddr; - memset(&serveraddr, 0, sizeof(serveraddr)); + struct sockaddr_in serveraddr = {0}; serveraddr.sin_family = AF_INET; - serveraddr.sin_port = htons(MDNS_PORT); + serveraddr.sin_port = htons(port); serveraddr.sin_addr.s_addr = htonl(INADDR_ANY); /* receive multicast */ if ((r = bind(sd, (struct sockaddr *)&serveraddr, sizeof(serveraddr))) < 0) { - log_message(LOG_ERR, "recv bind(): %m"); + log_message(LOG_ERR, "recv bind(): %s\n", strerror(errno)); } // add membership to receiving socket - struct ip_mreq mreq; - memset(&mreq, 0, sizeof(struct ip_mreq)); + DECL_ZERO_STRUCT(mreq, ip_mreq); mreq.imr_interface.s_addr = htonl(INADDR_ANY); - mreq.imr_multiaddr.s_addr = inet_addr(MDNS_ADDR); + mreq.imr_multiaddr.s_addr = inet_addr(addr); if ((r = setsockopt(sd, IPPROTO_IP, IP_ADD_MEMBERSHIP, (char *) &mreq, sizeof(mreq))) < 0) { - log_message(LOG_ERR, "recv setsockopt(IP_ADD_MEMBERSHIP): %m"); + close(sd); + log_message(LOG_ERR, "recv setsockopt(IP_ADD_MEMBERSHIP): %s\n", strerror(errno)); return r; } +#ifdef MDNS_ENABLE_LOOPBACK // enable loopback in case someone else needs the data - if ((r = setsockopt(sd, IPPROTO_IP, IP_MULTICAST_LOOP, (char *) &on, sizeof(on))) < 0) { - log_message(LOG_ERR, "recv setsockopt(IP_MULTICAST_LOOP): %m"); + int flag = 1; +#else + // disable loopback + int flag = 0; +#endif + if ((r = setsockopt(sd, IPPROTO_IP, IP_MULTICAST_LOOP, (char *)&flag, sizeof(flag))) < 0) { + close(sd); + log_message(LOG_ERR, "recv setsockopt(IP_MULTICAST_LOOP): %s\n", strerror(errno)); return r; } #ifdef IP_PKTINFO if ((r = setsockopt(sd, SOL_IP, IP_PKTINFO, (char *) &on, sizeof(on))) < 0) { - log_message(LOG_ERR, "recv setsockopt(IP_PKTINFO): %m"); + close(sd); + log_message(LOG_ERR, "recv setsockopt(IP_PKTINFO): %s\n", strerror(errno)); return r; } #endif @@ -154,18 +570,77 @@ static int create_recv_sock() { return sd; } -static ssize_t send_packet(int fd, const void *data, size_t len) { +static ssize_t send_packet(int fd, const void *data, size_t len, int domain) { static struct sockaddr_in toaddr; - if (toaddr.sin_family != AF_INET) { - memset(&toaddr, 0, sizeof(struct sockaddr_in)); - toaddr.sin_family = AF_INET; - toaddr.sin_port = htons(MDNS_PORT); - toaddr.sin_addr.s_addr = inet_addr(MDNS_ADDR); + char *addr; + int port; + + switch (domain) { +#if defined(CONFIG_NETUTILS_MDNS_XMDNS) + case MDNS_DOMAIN_SITE: + addr = CONFIG_NETUTILS_MDNS_XMDNS_MULTICAST_ADDR; + port = CONFIG_NETUTILS_MDNS_XMDNS_PORT_NUM; + break; +#endif + case MDNS_DOMAIN_LOCAL: + default: + addr = MDNS_ADDR; + port = MDNS_PORT; + break; } + memset(&toaddr, 0, sizeof(struct sockaddr_in)); + toaddr.sin_family = AF_INET; + toaddr.sin_port = htons(port); + toaddr.sin_addr.s_addr = inet_addr(addr); + return sendto(fd, data, len, 0, (struct sockaddr *) &toaddr, sizeof(struct sockaddr_in)); } +// populate the specified list which matches the RR name and type +static int populate_query(struct mdnsd *svr, struct rr_list **rr_head) +{ + int num_qns = 0; + struct rr_entry *qn_e = NULL; + + // check if we have the records + pthread_mutex_lock(&svr->data_lock); + + while (svr->query) { + qn_e = rr_list_remove(&svr->query, svr->query->e); + if (qn_e == NULL) { + break; + } + num_qns += rr_list_append(rr_head, qn_e); + } + + pthread_mutex_unlock(&svr->data_lock); + + return num_qns; +} + +#ifndef MDNS_NO_RESPONDER_SUPPORT + +// populate the specified list which matches the RR name and type +static int populate_probe(struct mdnsd *svr, struct rr_list **rr_head) +{ + int num_qns = 0; + + // check if we have the records + pthread_mutex_lock(&svr->data_lock); + + for (struct rr_entry *qn_e = NULL; svr->probe; ) { + qn_e = rr_list_remove(&svr->probe, svr->probe->e); + if (qn_e == NULL) { + break; + } + num_qns += rr_list_append(rr_head, qn_e); + } + + pthread_mutex_unlock(&svr->data_lock); + + return num_qns; +} // populate the specified list which matches the RR name and type // type can be RR_ANY, which populates all entries EXCEPT RR_NSEC @@ -175,20 +650,16 @@ static int populate_answers(struct mdnsd *svr, struct rr_list **rr_head, uint8_t // check if we have the records pthread_mutex_lock(&svr->data_lock); struct rr_group *ans_grp = rr_group_find(svr->group, name); - if (ans_grp == NULL) { - pthread_mutex_unlock(&svr->data_lock); - return num_ans; - } + if (ans_grp != NULL) { + // decide which records should go into answers + for (struct rr_list *n = ans_grp->rr; n; n = n->next) { + // exclude NSEC for RR_ANY + if (type == RR_ANY && n->e->type == RR_NSEC) + continue; - // decide which records should go into answers - struct rr_list *n = ans_grp->rr; - for (; n; n = n->next) { - // exclude NSEC for RR_ANY - if (type == RR_ANY && n->e->type == RR_NSEC) - continue; - - if ((type == n->e->type || type == RR_ANY) && cmp_nlabel(name, n->e->name) == 0) { - num_ans += rr_list_append(rr_head, n->e); + if ((type == n->e->type || type == RR_ANY) && cmp_nlabel(name, n->e->name) == 0) { + num_ans += rr_list_append(rr_head, n->e); + } } } @@ -237,11 +708,13 @@ static void add_related_rr(struct mdnsd *svr, struct rr_list *list, struct mdns_ static void announce_srv(struct mdnsd *svr, struct mdns_pkt *reply, uint8_t *name) { mdns_init_reply(reply, 0); + /* announce hostname and address */ + reply->num_ans_rr += populate_answers(svr, &reply->rr_ans, name, RR_A); + reply->num_ans_rr += populate_answers(svr, &reply->rr_ans, name, RR_AAAA); reply->num_ans_rr += populate_answers(svr, &reply->rr_ans, name, RR_PTR); - + // remember to add the services dns-sd PTR too - reply->num_ans_rr += populate_answers(svr, &reply->rr_ans, - SERVICES_DNS_SD_NLABEL, RR_PTR); + reply->num_ans_rr += populate_answers(svr, &reply->rr_ans, SERVICES_DNS_SD_NLABEL, RR_PTR); // see if we can match additional records for answers add_related_rr(svr, reply->rr_ans, reply); @@ -250,13 +723,196 @@ static void announce_srv(struct mdnsd *svr, struct mdns_pkt *reply, uint8_t *nam add_related_rr(svr, reply->rr_add, reply); } +static void process_for_probe(struct mdnsd *svr, struct mdns_pkt *mdns_packet) +{ + mdns_init_query(mdns_packet, 0); + + mdns_packet->num_qn += populate_probe(svr, &mdns_packet->rr_qn); +} + +#endif /* !defined MDNS_NO_RESPONDER_SUPPORT */ + +static void process_for_query(struct mdnsd *svr, struct mdns_pkt *mdns_packet) +{ + mdns_init_query(mdns_packet, 0); + + mdns_packet->num_qn += populate_query(svr, &mdns_packet->rr_qn); + +#ifndef MDNS_NO_RESPONDER_SUPPORT + // advertisement of my address to mdns neighbor + mdns_packet->num_ans_rr += populate_answers(svr, &mdns_packet->rr_add, svr->hostname, RR_A); + mdns_packet->num_ans_rr += populate_answers(svr, &mdns_packet->rr_add, svr->hostname, RR_AAAA); +#endif +} + +static void update_cache(struct mdnsd *svr) +{ + struct rr_list *remove_list = NULL; + + pthread_mutex_lock(&svr->data_lock); + for (struct rr_group *group = svr->cache; group; group = group->next) { + for (struct rr_list *list = group->rr; list; list = list->next) { + struct rr_entry *entry = list->e; + if (entry) { + /* if ttl is expired or rr is RR_PTR or RR_SRV, remove rr from cache */ + if (((time(NULL) - entry->update_time) > entry->ttl) || (svr->c_status != CACHE_SERVICE_DISCOVERY && (entry->type == RR_PTR || entry->type == RR_SRV))) { + rr_list_append(&remove_list, entry); + } + } + } + } + + /* remove ttl expired entry */ + for (struct rr_list *list = remove_list; list; list = list->next) { + struct rr_entry *entry = list->e; + if (entry) { + rr_group_del(&svr->cache, entry); + } + } + rr_list_destroy(remove_list, 0); /* destroy remove list */ + + pthread_mutex_unlock(&svr->data_lock); +} + +static void add_rr_to_cache(struct mdnsd *svr, struct mdns_pkt *pkt) +{ + struct rr_list *filtered_rr_list = NULL; + struct rr_list *srv_list = NULL; + struct rr_entry *a_e = NULL; + int b_found = 0; + + pthread_mutex_lock(&svr->data_lock); + + if (svr->c_status == CACHE_SLEEP) { + goto out_with_mutex; + } + + /* filtering */ + struct rr_list *rr_set[] = { + pkt->rr_ans, + pkt->rr_auth, + pkt->rr_add + }; + for (int i = 0; i < sizeof(rr_set) / sizeof(rr_set[0]); i++) { + for (struct rr_list *rr_l = rr_set[i]; rr_l; rr_l = rr_l->next) { + struct rr_entry *rr_e = rr_l->e; + if (rr_e) { + if (rr_e->type == RR_A || rr_e->type == RR_AAAA) { +#ifndef MDNS_NO_RESPONDER_SUPPORT + b_found = 1; + rr_list_append(&filtered_rr_list, rr_e); +#else + if (svr->c_status == CACHE_RESOLVE_HOSTNAME) { + if (svr->c_filter) { + char *name = nlabel_to_str(rr_e->name); + if (strncmp(name, svr->c_filter, strlen(svr->c_filter)) == 0) { + b_found = 1; + rr_list_append(&filtered_rr_list, rr_e); + } + MDNS_FREE(name); + } + } else if (svr->c_status == CACHE_SERVICE_DISCOVERY) { + rr_list_append(&filtered_rr_list, rr_e); + } +#endif /* !defined MDNS_NO_RESPONDER_SUPPORT */ + } else if (rr_e->type == RR_PTR) { + if (svr->c_status == CACHE_SERVICE_DISCOVERY) { + if (svr->c_filter) { + char *name = nlabel_to_str(rr_e->name); + if (strncmp(name, svr->c_filter, strlen(svr->c_filter)) == 0) { + b_found = 1; + rr_list_append(&filtered_rr_list, rr_e); + } + MDNS_FREE(name); + } + } + } else if (rr_e->type == RR_SRV) { + if (svr->c_status == CACHE_SERVICE_DISCOVERY) { + rr_list_append(&filtered_rr_list, rr_e); + } + } + } + } + } + + if (!b_found) { + if (filtered_rr_list) { + rr_list_destroy(filtered_rr_list, 0); + filtered_rr_list = NULL; + } + goto out_with_mutex; + } + + for (struct rr_list *rr_l = filtered_rr_list; rr_l; rr_l = rr_l->next) { + struct rr_entry *rr_e = rr_l->e; + + if (rr_e) { + struct rr_entry *cached_rr_e = NULL; + struct rr_group *group = rr_group_find(svr->cache, rr_e->name); + if (group) { + struct rr_entry *rr_e_in_cache = rr_entry_match(group->rr, rr_e); + if (rr_e_in_cache) { + rr_group_del(&svr->cache, rr_e_in_cache); + if (rr_e->ttl > 0) { + cached_rr_e = rr_duplicate(rr_e); + rr_group_add(&svr->cache, cached_rr_e); + } + } else { + cached_rr_e = rr_duplicate(rr_e); + rr_group_add(&svr->cache, cached_rr_e); + } + } else { + cached_rr_e = rr_duplicate(rr_e); + rr_group_add(&svr->cache, cached_rr_e); + } + + /* if SRV's target is null, add RR_A 's hostname to SRV's target */ + if (cached_rr_e) { + if (cached_rr_e->type == RR_SRV) { + rr_list_append(&srv_list, cached_rr_e); + } else if ((a_e == NULL) && (cached_rr_e->type == RR_A || cached_rr_e->type == RR_AAAA)) { + a_e = cached_rr_e; + } + } + } + } + + /* if SRV's target is null, add RR_A 's hostname to SRV's target */ + if (srv_list) { + if (a_e && a_e->name) { + for (struct rr_list *rr_l = srv_list; rr_l; rr_l = rr_l->next) { + struct rr_entry *rr_e = rr_l->e; + if (rr_e && (rr_e->data.SRV.target == NULL)) { + rr_e->data.SRV.target = dup_nlabel(a_e->name); + } + } + } + + rr_list_destroy(srv_list, 0); + srv_list = NULL; + } + + if (filtered_rr_list) { + rr_list_destroy(filtered_rr_list, 0); + filtered_rr_list = NULL; + } + +out_with_mutex: + pthread_mutex_unlock(&svr->data_lock); + + return; + +} + + // processes the incoming MDNS packet // returns >0 if processed, 0 otherwise static int process_mdns_pkt(struct mdnsd *svr, struct mdns_pkt *pkt, struct mdns_pkt *reply) { - int i; + int result; assert(pkt != NULL); +#ifndef MDNS_NO_RESPONDER_SUPPORT // is it standard query? if ((pkt->flags & MDNS_FLAG_RESP) == 0 && MDNS_FLAG_GET_OPCODE(pkt->flags) == 0) { @@ -270,13 +926,13 @@ static int process_mdns_pkt(struct mdnsd *svr, struct mdns_pkt *pkt, struct mdns // loop through questions struct rr_list *qnl = pkt->rr_qn; - for (i = 0; i < pkt->num_qn; i++, qnl = qnl->next) { + for (int i = 0; i < pkt->num_qn; i++, qnl = qnl->next) { struct rr_entry *qn = qnl->e; int num_ans_added = 0; char *namestr = nlabel_to_str(qn->name); DEBUG_PRINTF("qn #%d: type %s (%02x) %s - ", i, rr_get_type_name(qn->type), qn->type, namestr); - free(namestr); + MDNS_FREE(namestr); // check if it's a unicast query - we ignore those if (qn->unicast_query) { @@ -300,14 +956,14 @@ static int process_mdns_pkt(struct mdnsd *svr, struct mdns_pkt *pkt, struct mdns if (known_ans != NULL && known_ans->ttl >= ans->e->ttl / 2) { char *namestr = nlabel_to_str(ans->e->name); DEBUG_PRINTF("removing answer for %s\n", namestr); - free(namestr); + MDNS_FREE(namestr); // check if list item is head if (prev_ans == NULL) reply->rr_ans = ans->next; else prev_ans->next = ans->next; - free(ans); + MDNS_FREE(ans); ans = prev_ans; @@ -329,129 +985,304 @@ static int process_mdns_pkt(struct mdnsd *svr, struct mdns_pkt *pkt, struct mdns DEBUG_PRINTF("\n"); return reply->num_ans_rr; + } else { + result = 0; } +#else + result = 0; +#endif - return 0; + // if there is answer, add rr cache + if (pkt->num_ans_rr || pkt->num_auth_rr || pkt->num_add_rr) { + update_cache(svr); + add_rr_to_cache(svr, pkt); + } +#ifdef MDNSD_RR_DEBUG + print_cache(svr); +#endif +#ifdef MDNSD_MEMORY_DEBUG + mdns_show_meminfo(); +#endif + return result; } int create_pipe(int handles[2]) { -#ifdef _WIN32 - SOCKET sock = socket(AF_INET, SOCK_STREAM, 0); - if (sock == INVALID_SOCKET) { - return -1; - } +//#ifdef _WIN32 +#if (PIPE_SOCKET_TYPE == 1) + int result = -1; struct sockaddr_in serv_addr; + + handles[0] = -1; + handles[1] = -1; + + /* create 1st socket */ + handles[0] = socket(AF_INET, SOCK_DGRAM, 0); + if (handles[0] == -1) + goto errout; + memset(&serv_addr, 0, sizeof(serv_addr)); serv_addr.sin_family = AF_INET; - serv_addr.sin_port = htons(0); + serv_addr.sin_port = htons(PIPE_SOCKET_PORT0); serv_addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK); - if (bind(sock, (struct sockaddr*)&serv_addr, sizeof(serv_addr)) == SOCKET_ERROR) { - closesocket(sock); - return -1; + if (bind(handles[0], (struct sockaddr *)&serv_addr, sizeof(serv_addr)) == -1) + goto errout; + + if ((handles[1] = socket(PF_INET, SOCK_DGRAM, 0)) < 0) { + goto errout; +#if 0 /* this can be enabled for supporting bi-directional pipe */ + /* create 2nd socket */ + memset(&serv_addr, 0, sizeof(serv_addr)); + serv_addr.sin_family = AF_INET; + serv_addr.sin_port = htons(PIPE_SOCKET_PORT1); + serv_addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK); + + if (bind(handles[1], (struct sockaddr *)&serv_addr, sizeof(serv_addr)) == -1) + goto errout; +#endif + + /* success */ + result = 0; + return result; +errout: + for (int i = 0; i < 2; ++i) { + if (handles[i] != -1) { + close(handles[i]); + handles[i] = -1; + } } - if (listen(sock, 1) == SOCKET_ERROR) { - closesocket(sock); - return -1; - } - int len = sizeof(serv_addr); - if (getsockname(sock, (SOCKADDR*)&serv_addr, &len) == SOCKET_ERROR) { - closesocket(sock); - return -1; - } - if ((handles[1] = socket(PF_INET, SOCK_STREAM, 0)) == INVALID_SOCKET) { - closesocket(sock); - return -1; - } - if (connect(handles[1], (struct sockaddr*)&serv_addr, len) == SOCKET_ERROR) { - closesocket(sock); - return -1; - } - if ((handles[0] = accept(sock, (struct sockaddr*)&serv_addr, &len)) == INVALID_SOCKET) { - closesocket((SOCKET)handles[1]); - handles[1] = INVALID_SOCKET; - closesocket(sock); - return -1; - } - closesocket(sock); - return 0; + + return result; #else return pipe(handles); #endif } int read_pipe(int s, char* buf, int len) { -#ifdef _WIN32 - int ret = recv(s, buf, len, 0); - if (ret < 0 && WSAGetLastError() == WSAECONNRESET) { - ret = 0; - } - return ret; +//#ifdef _WIN32 +#if (PIPE_SOCKET_TYPE == 1) + struct sockaddr_in fromaddr; + socklen_t sockaddr_size = sizeof(struct sockaddr_in); + return recvfrom(s, buf, len, 0, (struct sockaddr *)&fromaddr, &sockaddr_size); #else return read(s, buf, len); #endif } -int write_pipe(int s, char* buf, int len) { -#ifdef _WIN32 - return send(s, buf, len, 0); +int write_pipe(int s, char *buf, int len, int port) { +//#ifdef _WIN32 +#if (PIPE_SOCKET_TYPE == 1) + static struct sockaddr_in toaddr; + + memset(&toaddr, 0, sizeof(struct sockaddr_in)); + toaddr.sin_family = AF_INET; + toaddr.sin_port = htons(port); + toaddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK); + + return sendto(s, buf, len, 0, (struct sockaddr *)&toaddr, sizeof(struct sockaddr_in)); #else return write(s, buf, len); #endif } int close_pipe(int s) { -#ifdef _WIN32 - return closesocket(s); -#else return close(s); -#endif +} + +static int request_sendmsg(struct mdnsd *svr) +{ + int ret; + struct timespec abstime; + const int wait_sec = 1; + const int wait_nsec = 0; + const int max_try_count = 3; + int try_count = 0; + int timeout = 0; + + do { + ret = write_pipe(svr->notify_pipe[1], ".", 1, PIPE_SOCKET_PORT0); + if (ret == -1) { + log_message(LOG_ERR, "write_pipe() failed. (ret=%d)\n", ret); + continue; + } + + (void)clock_gettime(CLOCK_REALTIME, &abstime); + abstime.tv_sec += wait_sec; + abstime.tv_nsec += wait_nsec; + if (abstime.tv_nsec >= NSEC_PER_SEC) { + abstime.tv_sec++; + abstime.tv_nsec -= NSEC_PER_SEC; + } + + timeout = 0; + while (sem_timedwait(&svr->sendmsg_sem, &abstime) != 0) { + int err = get_errno(); + assert(err == EINTR || err == ETIMEDOUT); + + if (err == ETIMEDOUT) { + timeout = 1; + break; + } + } + if (timeout) { + log_message(LOG_ERR, "sem_timedwait() timeout.\n"); + continue; + } + + break; + } while (++try_count < max_try_count); + + if (try_count == max_try_count) { + log_message(LOG_ERR, "request_sendmsg() failed.\n"); + return -1; + } + + return 0; } // main loop to receive, process and send out MDNS replies // also handles MDNS service announces static void main_loop(struct mdnsd *svr) { fd_set sockfd_set; - int max_fd = svr->sockfd; + int max_fd = 0; char notify_buf[2]; // buffer for reading of notify_pipe + int ret; + int econnreset_count = 0; + struct mdns_pkt *mdns_packet = NULL; - void *pkt_buffer = malloc(PACKET_SIZE); + void *pkt_buffer = MDNS_MALLOC(PACKET_SIZE); + if (pkt_buffer == NULL) { + log_message(LOG_ERR, "memory allocation : pkt_buffer\n"); + goto out; + } + mdns_packet = MDNS_MALLOC(sizeof(struct mdns_pkt)); + if (mdns_packet == NULL) { + log_message(LOG_ERR, "memory allocation : mdns_packet\n"); + goto out; + } + memset(mdns_packet, 0, sizeof(struct mdns_pkt)); + + max_fd = svr->sockfd; if (svr->notify_pipe[0] > max_fd) max_fd = svr->notify_pipe[0]; - struct mdns_pkt *mdns_reply = malloc(sizeof(struct mdns_pkt)); - memset(mdns_reply, 0, sizeof(struct mdns_pkt)); + while (1) { + svr->sendmsg_requested = 0; - while (! svr->stop_flag) { FD_ZERO(&sockfd_set); FD_SET(svr->sockfd, &sockfd_set); FD_SET(svr->notify_pipe[0], &sockfd_set); - select(max_fd + 1, &sockfd_set, NULL, NULL, NULL); + ret = select(max_fd + 1, &sockfd_set, NULL, NULL, NULL); - if (FD_ISSET(svr->notify_pipe[0], &sockfd_set)) { - // flush the notify_pipe - read_pipe(svr->notify_pipe[0], (char*)¬ify_buf, 1); - } else if (FD_ISSET(svr->sockfd, &sockfd_set)) { - struct sockaddr_in fromaddr; - socklen_t sockaddr_size = sizeof(struct sockaddr_in); + if (ret > 0) { + if (FD_ISSET(svr->notify_pipe[0], &sockfd_set)) { + svr->sendmsg_requested = 1; + // flush the notify_pipe + if (read_pipe(svr->notify_pipe[0], (char *)¬ify_buf, 1) == -1) + log_message(LOG_ERR, "read_pipe() failed; %m\n"); + } else if (FD_ISSET(svr->sockfd, &sockfd_set)) { + struct sockaddr_in fromaddr; + socklen_t sockaddr_size = sizeof(struct sockaddr_in); - ssize_t recvsize = recvfrom(svr->sockfd, pkt_buffer, PACKET_SIZE, 0, - (struct sockaddr *) &fromaddr, &sockaddr_size); - if (recvsize < 0) { - log_message(LOG_ERR, "recv(): %m"); - } + ssize_t recvsize = recvfrom(svr->sockfd, pkt_buffer, PACKET_SIZE, 0, + (struct sockaddr *) &fromaddr, &sockaddr_size); + if (recvsize < 0) { + int errval = errno; + log_message(LOG_ERR, "recv failed(): recvsize: %d; %s\n", recvsize, strerror(errno)); + if (errval == ECONNRESET) { + econnreset_count++; + if (econnreset_count >= MAX_ECONNRESET_COUNT) { + int remaining_cnt; + log_message(LOG_ERR, "ECONNRESET occurred %d times. recv socket will be recreated.\n", econnreset_count); - DEBUG_PRINTF("data from=%s size=%ld\n", inet_ntoa(fromaddr.sin_addr), (long) recvsize); - struct mdns_pkt *mdns = mdns_parse_pkt(pkt_buffer, recvsize); - if (mdns != NULL) { - if (process_mdns_pkt(svr, mdns, mdns_reply)) { - size_t replylen = mdns_encode_pkt(mdns_reply, pkt_buffer, PACKET_SIZE); - send_packet(svr->sockfd, pkt_buffer, replylen); - } else if (mdns->num_qn == 0) { - DEBUG_PRINTF("(no questions in packet)\n\n"); + /* close and recreate recv socket */ + close(svr->sockfd); + remaining_cnt = 3; + while (remaining_cnt) { + svr->sockfd = create_recv_sock(svr->domain); + if (svr->sockfd != -1) { + /* succeed to create recv socket */ + break; + } + remaining_cnt--; + } + if (svr->sockfd == -1) { + log_message(LOG_ERR, "fail to recreate recv socket. mdnsd main_loop will be terminated.\n"); + break; /* exit loop */ + } + + if (svr->sockfd > max_fd) { + max_fd = svr->sockfd; + } + econnreset_count = 0; + } + } + + continue; } - mdns_pkt_destroy(mdns); + DEBUG_PRINTF("data from=%s size=%ld\n", inet_ntoa(fromaddr.sin_addr), (long) recvsize); + struct mdns_pkt *mdns = mdns_parse_pkt(pkt_buffer, recvsize); + if (mdns != NULL) { + if (process_mdns_pkt(svr, mdns, mdns_packet)) { +#ifdef MDNS_NO_RESPONDER_SUPPORT + size_t replylen = mdns_encode_pkt(mdns_packet, pkt_buffer, PACKET_SIZE); + if (send_packet(svr->sockfd, pkt_buffer, replylen, svr->domain) == -1) + log_message(LOG_ERR, "send_packet() failed; %m\n"); +#endif + } else if (mdns->num_qn == 0) { + DEBUG_PRINTF("(no questions in packet)\n\n"); + } + mdns_pkt_destroy(mdns); + } + } + } else { + log_message(LOG_ERR, "select() failed (ret: %d); %m\n", ret); + continue; + } + + // send out query + while (1) { + if (!svr->query) { + break; + } + + process_for_query(svr, mdns_packet); + if (mdns_packet->num_qn > 0) { + + DEBUG_PRINTF("sending query : (num of qn = %d)\n", mdns_packet->num_qn); + + size_t replylen = mdns_encode_pkt(mdns_packet, pkt_buffer, PACKET_SIZE); + if (send_packet(svr->sockfd, pkt_buffer, replylen, svr->domain) == -1) { + log_message(LOG_ERR, "send_packet() failed. (errno: %d)\n", errno); + } + + if (mdns_packet->rr_qn) { + rr_list_destroy(mdns_packet->rr_qn, 1); + mdns_packet->rr_qn = NULL; + } + } + } + +#ifndef MDNS_NO_RESPONDER_SUPPORT + // send out probe + while (1) { + if (!svr->probe) { + break; + } + + process_for_probe(svr, mdns_packet); + if (mdns_packet->num_qn > 0) { + DEBUG_PRINTF("sending query for probe : (num of qn = %d)\n", mdns_packet->num_qn); + size_t replylen = mdns_encode_pkt(mdns_packet, pkt_buffer, PACKET_SIZE); + if (send_packet(svr->sockfd, pkt_buffer, replylen, svr->domain) == -1) { + log_message(LOG_ERR, "send_packet() failed; %m\n"); + } + + if (mdns_packet->rr_qn) { + rr_list_destroy(mdns_packet->rr_qn, 1); + mdns_packet->rr_qn = NULL; + } } } @@ -470,48 +1301,887 @@ static void main_loop(struct mdnsd *svr) { char *namestr = nlabel_to_str(ann_e->name); DEBUG_PRINTF("sending announce for %s\n", namestr); - free(namestr); + MDNS_FREE(namestr); - announce_srv(svr, mdns_reply, ann_e->name); + announce_srv(svr, mdns_packet, ann_e->name); - if (mdns_reply->num_ans_rr > 0) { - size_t replylen = mdns_encode_pkt(mdns_reply, pkt_buffer, PACKET_SIZE); - send_packet(svr->sockfd, pkt_buffer, replylen); + if (mdns_packet->num_ans_rr > 0) { + size_t replylen = mdns_encode_pkt(mdns_packet, pkt_buffer, PACKET_SIZE); + if (send_packet(svr->sockfd, pkt_buffer, replylen, svr->domain) == -1) + log_message(LOG_ERR, "send_packet() failed; %s\n", strerror(errno)); + } + } +#endif /* !defined MDNS_NO_RESPONDER_SUPPORT */ + + if (svr->sendmsg_requested) { + if (svr->stop_flag) + break; /* exit main_loop */ + sem_post(&svr->sendmsg_sem); + } + } + + if (svr->sendmsg_requested && svr->stop_flag) { + // sem_post() should be executed in order to awaken mdnsd_stop(), + // because main_loop is terminated before executing sem_post() + sem_post(&svr->sendmsg_sem); + } + // main thread terminating. send out "goodbye packets" for services + mdns_init_reply(mdns_packet, 0); + +#ifndef MDNS_NO_RESPONDER_SUPPORT + pthread_mutex_lock(&svr->data_lock); + for (struct rr_list *svc_le = svr->services; svc_le; svc_le = svc_le->next) { + // set TTL to zero + svc_le->e->ttl = 0; + mdns_packet->num_ans_rr += rr_list_append(&mdns_packet->rr_ans, svc_le->e); + } + pthread_mutex_unlock(&svr->data_lock); +#endif + + // send out packet + if (mdns_packet->num_ans_rr > 0) { + if (svr->sockfd != -1) { + size_t replylen = mdns_encode_pkt(mdns_packet, pkt_buffer, PACKET_SIZE); + if (send_packet(svr->sockfd, pkt_buffer, replylen, svr->domain) == -1) { + log_message(LOG_ERR, "send_packet() failed; %s\n", strerror(errno)); } } } - // main thread terminating. send out "goodbye packets" for services - mdns_init_reply(mdns_reply, 0); - - pthread_mutex_lock(&svr->data_lock); - struct rr_list *svc_le = svr->services; - for (; svc_le; svc_le = svc_le->next) { - // set TTL to zero - svc_le->e->ttl = 0; - mdns_reply->num_ans_rr += rr_list_append(&mdns_reply->rr_ans, svc_le->e); - } - pthread_mutex_unlock(&svr->data_lock); - - // send out packet - if (mdns_reply->num_ans_rr > 0) { - size_t replylen = mdns_encode_pkt(mdns_reply, pkt_buffer, PACKET_SIZE); - send_packet(svr->sockfd, pkt_buffer, replylen); - } - +out: // destroy packet - mdns_init_reply(mdns_reply, 0); - free(mdns_reply); + if (mdns_packet) { + mdns_init_reply(mdns_packet, 0); + MDNS_FREE(mdns_packet); + mdns_packet = NULL; + } - free(pkt_buffer); + if (pkt_buffer) { + MDNS_FREE(pkt_buffer); + pkt_buffer = NULL; + } - close_pipe(svr->sockfd); + if (svr->sockfd != -1) { + close(svr->sockfd); + svr->sockfd = -1; + } svr->stop_flag = 2; } +#ifndef MDNS_NO_RESPONDER_SUPPORT +static int probe_hostname(struct mdnsd *svr, char *hostname) +{ + int result = 1; + int i; + + struct rr_entry *probe_e = NULL; + uint8_t *name; + + pthread_mutex_lock(&svr->data_lock); + svr->c_status = CACHE_RESOLVE_HOSTNAME; + if (svr->c_filter) { + MDNS_FREE(svr->c_filter); + svr->c_filter = MDNS_STRDUP(hostname); + } + pthread_mutex_unlock(&svr->data_lock); + + for (i = 0; i < 3; i++) { + /* make query with RR_ANY for probe hostname */ + name = create_nlabel(hostname); + probe_e = qn_create(name, RR_ANY, 0); + + pthread_mutex_lock(&svr->data_lock); + + rr_list_append(&svr->probe, probe_e); + + pthread_mutex_unlock(&svr->data_lock); + + request_sendmsg(svr); + + usleep(250 * 1000); // 250ms delay + + if (lookup_hostname(svr, hostname) == 0) { + result = 0; + break; + } + } + + pthread_mutex_lock(&svr->data_lock); + svr->c_status = CACHE_NORMAL; + if (svr->c_filter) { + MDNS_FREE(svr->c_filter); + svr->c_filter = NULL; + } + pthread_mutex_unlock(&svr->data_lock); + + return result; +} +#endif + +static void init_service_discovery_result(struct mdns_service_info + *service_list, int num_of_services) +{ + if (service_list == NULL) { + log_message(LOG_ERR, "mdns_service_info is null.\n"); + return; + } + + for (int i = 0; i < num_of_services; i++) { + service_list[i].type = NULL; + service_list[i].instance_name = NULL; + service_list[i].hostname = NULL; + service_list[i].ipaddr = 0; + service_list[i].port = 0; + } +} + +static void clear_service_discovery_result(struct mdns_service_info + *service_list, int num_of_services) +{ + if (service_list == NULL) { + log_message(LOG_ERR, "service_list is null.\n"); + return; + } + + for (int i = 0; i < num_of_services; i++) { + if (service_list[i].type) { + MDNS_FREE(service_list[i].type); + service_list[i].type = NULL; + } + + if (service_list[i].instance_name) { + MDNS_FREE(service_list[i].instance_name); + service_list[i].instance_name = NULL; + } + + if (service_list[i].hostname) { + MDNS_FREE(service_list[i].hostname); + service_list[i].hostname = NULL; + } + + service_list[i].ipaddr = 0; + service_list[i].port = 0; + } +} + +static void destroy_service_discovery_result(struct mdns_service_info + *service_list, int num_of_services) +{ + if (service_list == NULL) { + log_message(LOG_ERR, "service_list is null.\n"); + return; + } + + clear_service_discovery_result(service_list, num_of_services); + + MDNS_FREE(service_list); +} + +#ifndef MDNS_NO_RESPONDER_SUPPORT +static int mdnsd_set_host_info(struct mdnsd *svr, const char *hostname, uint32_t ipaddr) +{ + int result = -1; + struct rr_entry *a_e = NULL, *nsec_e = NULL; + int domain; + char mdns_suffix[16]; + + if (svr == NULL) { + log_message(LOG_ERR, "mdnsd instance handle is null.\n"); + goto done; + } + + domain = check_mdns_domain(hostname); + if (domain == MDNS_DOMAIN_LOCAL) { + snprintf(mdns_suffix, sizeof(mdns_suffix), MDNS_SUFFIX_LOCAL); + } +#if defined(CONFIG_NETUTILS_MDNS_XMDNS) + else if (domain == MDNS_DOMAIN_SITE) { + snprintf(mdns_suffix, sizeof(mdns_suffix), MDNS_SUFFIX_SITE); + } +#endif + else { + log_message(LOG_ERR, "mdnsd hostname is invalid.\n"); + goto done; + } + + if (ipaddr == 0) { + log_message(LOG_ERR, "mdnsd ip address is not set.\n"); + goto done; + } + + int need_probe = 1; + uint8_t *hname_nlabel = create_nlabel(hostname); + if (svr->hostname && svr->hostname_org) { + if ((strcmp((char *)hname_nlabel, (char *)svr->hostname_org) == 0) || (strcmp((char *)hname_nlabel, (char *)svr->hostname) == 0)) { + need_probe = 0; + } + } + MDNS_FREE(hname_nlabel); + + char hname[128]; + if (need_probe) { + // probe hostname collision + char *str; + snprintf(hname, sizeof(hname), hostname); + int alternative_hostname = 0; + int no = 2; + while (probe_hostname(svr, hname) == 0) { + /* when name conflict occurs */ + snprintf(hname, sizeof(hname), hostname); + str = strstr(hname, mdns_suffix); + if (str) { + snprintf(str, sizeof(hname), "(%d)%s", no++, mdns_suffix); + alternative_hostname = 1; + } else { + log_message(LOG_ERR, "cannot set an alternative hostname.\n"); + } + } + + // if there is previous hostname information, delete it + if (svr->hostname) { + if (svr->hostname == svr->hostname_org) { + MDNS_FREE(svr->hostname); + svr->hostname = NULL; + svr->hostname_org = NULL; + } else { + MDNS_FREE(svr->hostname); + svr->hostname = NULL; + + MDNS_FREE(svr->hostname_org); + svr->hostname_org = NULL; + } + } + // set hostname information + if (alternative_hostname) { + svr->hostname = create_nlabel(hname); + svr->hostname_org = create_nlabel(hostname); + } else { + svr->hostname = create_nlabel(hname); + svr->hostname_org = svr->hostname; + } + } + + char *hname_str = nlabel_to_str(svr->hostname); + int hname_strlen = strlen(hname_str); + hname_str[hname_strlen - 1] = '\0'; + + a_e = rr_create_a(create_nlabel(hname_str), ipaddr); + nsec_e = rr_create(create_nlabel(hname_str), RR_NSEC); + rr_set_nsec(nsec_e, RR_A); + MDNS_FREE(hname_str); + + pthread_mutex_lock(&svr->data_lock); + rr_group_add(&svr->group, a_e); + rr_group_add(&svr->group, nsec_e); + + // append RR_A entry to announce list + rr_list_append(&svr->announce, a_e); + + pthread_mutex_unlock(&svr->data_lock); + + request_sendmsg(svr); + + /* success */ + result = 0; + +done: + return result; +} + +/* +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + + +static const char * flags(int sd, const char * name) +{ + static char buf[1024]; + + static struct ifreq ifreq; + strcpy(ifreq.ifr_name, name); + + int r = ioctl(sd, SIOCGIFFLAGS, (char *)&ifreq); + assert(r == 0); + + int l = 0; +#define FLAG(b) if(ifreq.ifr_flags & b) l += snprintf(buf + l, sizeof(buf) - l, #b " ") + FLAG(IFF_UP); + FLAG(IFF_BROADCAST); + FLAG(IFF_DEBUG); + FLAG(IFF_LOOPBACK); + FLAG(IFF_POINTOPOINT); + FLAG(IFF_RUNNING); + FLAG(IFF_NOARP); + FLAG(IFF_PROMISC); + FLAG(IFF_NOTRAILERS); + FLAG(IFF_ALLMULTI); + FLAG(IFF_MASTER); + FLAG(IFF_SLAVE); + FLAG(IFF_MULTICAST); + FLAG(IFF_PORTSEL); + FLAG(IFF_AUTOMEDIA); + FLAG(IFF_DYNAMIC); +#undef FLAG + + return buf; +} +*/ + +int netlib_get_ipv4addr(const char *ifname, struct in_addr *addr) { + int result = -1; + int sd; + + struct ifreq ifreqs[8]; + struct ifconf ifconf = {0}; + + ifconf.ifc_req = ifreqs; + ifconf.ifc_len = sizeof(ifreqs); + + sd = socket(PF_INET, SOCK_STREAM, 0); + do { + if (sd < 0) break; + + int r = ioctl(sd, SIOCGIFCONF, (char *)&ifconf); + if (r != 0) break; + + for (int i = 0; i < ifconf.ifc_len/sizeof(struct ifreq); ++i) + { + /* printf("%s: %s\n", ifreqs[i].ifr_name, inet_ntoa(((struct sockaddr_in *)&ifreqs[i].ifr_addr)->sin_addr)); + printf(" flags: %s\n", flags(sd, ifreqs[i].ifr_name)); + */ + if (0 == strcmp( ifname, ifreqs[i].ifr_name)) { + *addr = ((struct sockaddr_in *)&ifreqs[i].ifr_addr)->sin_addr; + result = 0; + break; + } + } + } while (0); + + close(sd); + return result; +} + +static int mdnsd_set_host_info_by_netif(struct mdnsd *svr, const char *hostname, const char *netif_nameOrAddress) +{ + int result = -1; + struct in_addr ipaddr; + + if (svr == NULL) { + log_message(LOG_ERR, "mdnsd instance handle is null.\n"); + goto done; + } + + if ((in_addr_t)(-1) == (ipaddr.s_addr = inet_addr(netif_nameOrAddress))) { + result = netlib_get_ipv4addr(netif_nameOrAddress, &ipaddr); + if (result < 0) + return result; + } + + result = mdnsd_set_host_info(svr, hostname, ipaddr.s_addr); + +done: + return result; +} +#endif /* !defined MDNS_NO_RESPONDER_SUPPORT */ + +static int init_mdns_context(int domain) +{ + int result = -1; + pthread_t tid; + pthread_attr_t attr; + + if (g_svr) { + log_message(LOG_ERR, "mdnsd is running.\n"); + goto out; + } + + g_svr = MDNS_MALLOC(sizeof(struct mdnsd)); + if (g_svr == NULL) { + log_message(LOG_ERR, "memory allocation failed.\n"); + goto errout; + } + + /* initialize struct mdnsd instance */ + memset(g_svr, 0, sizeof(struct mdnsd)); + g_svr->stop_flag = 0; + g_svr->sockfd = -1; + g_svr->notify_pipe[0] = -1; + g_svr->notify_pipe[1] = -1; + + switch (domain) { +#if defined(CONFIG_NETUTILS_MDNS_XMDNS) + case MDNS_DOMAIN_SITE: +#endif + case MDNS_DOMAIN_LOCAL: + g_svr->domain = domain; + break; + case MDNS_DOMAIN_UNKNOWN: + default: + log_message(LOG_ERR, "invalid domain type.\n"); + goto errout; + } + + if (create_pipe(g_svr->notify_pipe) != 0) { + log_message(LOG_ERR, "create_pipe() failed.\n"); + goto errout; + } + + g_svr->sockfd = create_recv_sock(domain); + if (g_svr->sockfd < 0) { + log_message(LOG_ERR, "create_recv_sock() failed.\n"); + goto errout; + } + + /* memory allocation for service discovery */ + if (g_service_list == NULL) { + g_service_list = (struct mdns_service_info *)MDNS_MALLOC(sizeof(struct mdns_service_info) * MAX_NUMBER_OF_SERVICE_DISCOVERY_RESULT); + if (g_service_list == NULL) { + goto errout; + } + init_service_discovery_result(g_service_list, MAX_NUMBER_OF_SERVICE_DISCOVERY_RESULT); + } + + pthread_mutex_init(&g_svr->data_lock, NULL); + sem_init(&g_svr->sendmsg_sem, 0, 0); + g_svr->sendmsg_requested = 1; + + /* init thread */ + if (pthread_attr_init(&attr) != 0) { + log_message(LOG_ERR, "pthread_attr_init() failed.\n"); + goto errout_with_mutex; + } +#ifdef PTHREAD_CREATE_DETACHED_SUPPORTED /* PTHREAD_CREATE_DETACHED is not supported in tinyara */ + pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); +#endif + + size_t stksiz; + if (pthread_attr_getstacksize(&attr, &stksiz) == 0 && stksiz < THREAD_MAINLOOP_STACKSIZE) { + if (pthread_attr_setstacksize(&attr, THREAD_MAINLOOP_STACKSIZE) != 0) { + log_message(LOG_ERR, "pthread_attr_setstacksize() failed.\n"); + goto errout_with_mutex; + } + } + + /* create main_loop thread */ + if ((pthread_create(&tid, &attr, (void * (*)(void *))main_loop, (void *)g_svr) != 0)) { + log_message(LOG_ERR, "pthread_create() failed.\n"); + goto errout_with_mutex; + } + +#ifdef PTHREAD_SETNAME_SUPPORTED + pthread_setname_np(tid, THREAD_MAINLOOP_NAME); +#endif +#ifndef PTHREAD_CREATE_DETACHED_SUPPORTED + if (pthread_detach(tid) != 0) { + log_message(LOG_ERR, "pthread_detach() failed.\n"); + } +#endif + + /* wait until main_loop starts */ + while (g_svr->sendmsg_requested == 1) { + if (g_svr->stop_flag) { + goto errout_with_mutex; + } + + usleep(10 * 1000); + } + +#ifndef MDNS_NO_RESPONDER_SUPPORT + g_svr->c_status = CACHE_NORMAL; +#else + g_svr->c_status = CACHE_SLEEP; +#endif + + /* success */ + result = 0; + +out: + return result; + +errout_with_mutex: + if (g_svr) { + pthread_mutex_destroy(&g_svr->data_lock); + sem_destroy(&g_svr->sendmsg_sem); + } + +errout: + if (g_svr) { + if (g_svr->sockfd != -1) { + close(g_svr->sockfd); + g_svr->sockfd = -1; + } + + if (g_svr->notify_pipe[0] != -1) { + close_pipe(g_svr->notify_pipe[0]); + g_svr->notify_pipe[0] = -1; + } + + if (g_svr->notify_pipe[1] != -1) { + close_pipe(g_svr->notify_pipe[1]); + g_svr->notify_pipe[1] = -1; + } + + MDNS_FREE(g_svr); + g_svr = NULL; + } + + if (g_service_list) { + destroy_service_discovery_result(g_service_list, MAX_NUMBER_OF_SERVICE_DISCOVERY_RESULT); + g_service_list = NULL; + } + + return result; +} + +static void release_mdns_context_resource(void) +{ + if (g_svr->notify_pipe[0] != -1) { + close_pipe(g_svr->notify_pipe[0]); + g_svr->notify_pipe[0] = -1; + } + if (g_svr->notify_pipe[1] != -1) { + close_pipe(g_svr->notify_pipe[1]); + g_svr->notify_pipe[1] = -1; + } + + pthread_mutex_destroy(&g_svr->data_lock); + sem_destroy(&g_svr->sendmsg_sem); + + rr_group_destroy(g_svr->cache); + g_svr->cache = NULL; + + rr_list_destroy(g_svr->query, 0); + g_svr->query = NULL; + + if (g_svr->c_filter) { + MDNS_FREE(g_svr->c_filter); + g_svr->c_filter = NULL; + } +#ifndef MDNS_NO_RESPONDER_SUPPORT + rr_group_destroy(g_svr->group); + g_svr->group = NULL; + + rr_list_destroy(g_svr->announce, 0); + g_svr->announce = NULL; + + rr_list_destroy(g_svr->services, 0); + g_svr->services = NULL; + + rr_list_destroy(g_svr->probe, 0); + g_svr->probe = NULL; + + if (g_svr->hostname == g_svr->hostname_org) { + if (g_svr->hostname) { + MDNS_FREE(g_svr->hostname); + g_svr->hostname = NULL; + g_svr->hostname_org = NULL; + } + } else { + if (g_svr->hostname) { + MDNS_FREE(g_svr->hostname); + g_svr->hostname = NULL; + } + if (g_svr->hostname_org) { + MDNS_FREE(g_svr->hostname_org); + g_svr->hostname_org = NULL; + } + } + + if (g_service_list) { + /* free memory for service discovery */ + destroy_service_discovery_result(g_service_list, MAX_NUMBER_OF_SERVICE_DISCOVERY_RESULT); + g_service_list = NULL; + } +#endif /* !defined MDNS_NO_RESPONDER_SUPPORT */ + + g_svr->domain = MDNS_DOMAIN_UNKNOWN; + + MDNS_FREE(g_svr); + g_svr = NULL; +} + +static int destroy_mdns_context(void) +{ + int result = -1; + + if (g_svr == NULL) { + log_message(LOG_ERR, "mdnsd is not running.\n"); + goto done; + } + + g_svr->stop_flag = 1; + + request_sendmsg(g_svr); + + while (g_svr->stop_flag != 2) { + usleep(500 * 1000); + } + + release_mdns_context_resource(); + + /* success */ + result = 0; + +done: +#ifdef MDNSD_MEMORY_DEBUG + mdns_show_meminfo(); +#endif + + return result; +} + +static void mdns_cmd_mutex_lock(void) +{ + if (!g_cmd_lock_initialized) { + if (pthread_mutex_init(&g_cmd_lock, NULL) != 0) { + log_message(LOG_ERR, "pthread_mutex_init() failed.\n"); + return; + } + g_cmd_lock_initialized = 1; + } + + if (g_cmd_lock_initialized) { + pthread_mutex_lock(&g_cmd_lock); + } +} + +static void mdns_cmd_mutex_unlock(void) +{ + if (g_cmd_lock_initialized) { + pthread_mutex_unlock(&g_cmd_lock); + } +} + +///////////////////////////////////////////////////// +// Public Functions ///////////////////////////////////////////////////// +#ifndef MDNS_NO_RESPONDER_SUPPORT + +/**************************************************************************** + * Name: mdnsd_start + * + * Description: + * Starts the MDNS daemon. + * + * Parameters: + * desired_hostname : the desired host name as string type. if same name is in the network, + * an alternative name will be set as hostname. + * netif_name : network interface name as string type + * + * Returned Value: + * On success, 0 is returned. On failure, a negative value is returned. + * + ****************************************************************************/ +int mdnsd_start(const char *desired_hostname, const char *netif_nameOrAddress) +{ + int result = -1; + int domain; + + mdns_cmd_mutex_lock(); + + domain = check_mdns_domain(desired_hostname); + if (init_mdns_context(domain) != 0) { + goto out_with_mutex; + } + + /* set hostname and ip address */ + if (mdnsd_set_host_info_by_netif(g_svr, desired_hostname, netif_nameOrAddress) != 0) { + if (destroy_mdns_context() != 0) { + log_message(LOG_ERR, "mdnsd_set_host_info_by_netif() and destroy_mdns_context() failed.\n"); + } + + goto out_with_mutex; + } + + /* success */ + result = 0; + +out_with_mutex: + mdns_cmd_mutex_unlock(); + return result; +} + +/**************************************************************************** + * Name: mdnsd_stop + * + * Description: + * Stops the MDNS daemon. + * + * Returned Value: + * On success, 0 is returned. On failure, a negative value is returned. + * + ****************************************************************************/ +int mdnsd_stop(void) +{ + int result = -1; + + mdns_cmd_mutex_lock(); + + if (destroy_mdns_context() != 0) { + goto out_with_mutex; + } + + /* success */ + result = 0; + +out_with_mutex: + mdns_cmd_mutex_unlock(); + return result; +} + +/**************************************************************************** + * Name: mdnsd_get_hostname + * + * Description: + * Gets the current host name as MDNS type. + * + * Parameters: + * hostname_result : 32-bytes string buffer for the host name result + * + * Returned Value: + * On success, 0 is returned. On failure, a negative value is returned. + * + ****************************************************************************/ +int mdnsd_get_hostname(char *hostname_result) +{ + int result = -1; + if (g_svr == NULL) { + log_message(LOG_ERR, "mdnsd is not running.\n"); + goto out; + } + + mdns_cmd_mutex_lock(); + + char *hname = nlabel_to_str(g_svr->hostname); + int hname_len = strlen(hname); + hname_len = (hname_len > 32) ? 32 : hname_len; + hname[hname_len - 1] = '\0'; + strncpy(hostname_result, hname, 32); + MDNS_FREE(hname); + + /* success */ + result = 0; + + mdns_cmd_mutex_unlock(); + +out: + return result; +} + +static void mdns_service_destroy(struct mdns_service *srv) +{ + assert(srv != NULL); + rr_list_destroy(srv->entries, 0); + MDNS_FREE(srv); +} + +int mdnsd_register_service(const char *instance_name, + const char *type, uint16_t port, const char *hostname, const char *txt[]) { + struct rr_entry *txt_e = NULL, + *srv_e = NULL, + *ptr_e = NULL, + *bptr_e = NULL; + uint8_t *target; + uint8_t *inst_nlabel, *type_nlabel, *nlabel; + struct mdns_service *service = NULL; + if (g_svr == NULL) { + log_message(LOG_ERR, "mdnsd is not running.\n"); + goto out; + } + + if (check_mdns_domain(type) == MDNS_DOMAIN_UNKNOWN) { + log_message(LOG_ERR, "service type is invalid. service type should be " +#if defined(CONFIG_NETUTILS_MDNS_XMDNS) + "%s or %s domain.\n", MDNS_SUFFIX_LOCAL, MDNS_SUFFIX_SITE); +#else + "%s domain.\n", MDNS_SUFFIX_LOCAL); +#endif + goto out; + } + + mdns_cmd_mutex_lock(); + + service = (struct mdns_service *)MDNS_MALLOC(sizeof(struct mdns_service)); + if (service == NULL) { + log_message(LOG_ERR, "memory allocation failed.\n"); + goto out_with_mutex; + } + memset(service, 0, sizeof(struct mdns_service)); + + // combine service name + type_nlabel = create_nlabel(type); + inst_nlabel = create_nlabel(instance_name); + nlabel = join_nlabel(inst_nlabel, type_nlabel); + + // create TXT record + if (txt && *txt) { + txt_e = rr_create(dup_nlabel(nlabel), RR_TXT); + rr_list_append(&service->entries, txt_e); + + // add TXTs + for (; *txt; txt++) + rr_add_txt(txt_e, *txt); + } + + // create SRV record + assert(hostname || g_svr->hostname); // either one as target + target = hostname ? + create_nlabel(hostname) : + dup_nlabel(g_svr->hostname); + + srv_e = rr_create_srv(dup_nlabel(nlabel), port, target); + rr_list_append(&service->entries, srv_e); + + // create PTR record for type + ptr_e = rr_create_ptr(type_nlabel, srv_e); + + // create services PTR record for type + // this enables the type to show up as a "service" + bptr_e = rr_create_ptr(dup_nlabel(SERVICES_DNS_SD_NLABEL), ptr_e); + + // modify lists here + pthread_mutex_lock(&g_svr->data_lock); + + if (txt_e) + rr_group_add(&g_svr->group, txt_e); + rr_group_add(&g_svr->group, srv_e); + rr_group_add(&g_svr->group, ptr_e); + rr_group_add(&g_svr->group, bptr_e); + + // append PTR entry to announce list + rr_list_append(&g_svr->announce, ptr_e); + rr_list_append(&g_svr->services, ptr_e); + + pthread_mutex_unlock(&g_svr->data_lock); + + // don't free type_nlabel - it's with the PTR record + MDNS_FREE(nlabel); + MDNS_FREE(inst_nlabel); + + // notify server + request_sendmsg(g_svr); + + mdns_service_destroy(service); + + /* result is success */ + int result = 0; + +out_with_mutex: + mdns_cmd_mutex_unlock(); + +out: + return result; +} void mdnsd_set_hostname(struct mdnsd *svr, const char *hostname, uint32_t ip) { struct rr_entry *a_e = NULL, @@ -538,140 +2208,289 @@ void mdnsd_add_rr(struct mdnsd *svr, struct rr_entry *rr) { rr_group_add(&svr->group, rr); pthread_mutex_unlock(&svr->data_lock); } +#endif /* !defined MDNS_NO_RESPONDER_SUPPORT */ -struct mdns_service *mdnsd_register_svc(struct mdnsd *svr, const char *instance_name, - const char *type, uint16_t port, const char *hostname, const char *txt[]) { - struct rr_entry *txt_e = NULL, - *srv_e = NULL, - *ptr_e = NULL, - *bptr_e = NULL; - uint8_t *target; - uint8_t *inst_nlabel, *type_nlabel, *nlabel; - struct mdns_service *service = malloc(sizeof(struct mdns_service)); - memset(service, 0, sizeof(struct mdns_service)); +/**************************************************************************** + * Name: mdnsd_resolve_hostname + * + * Description: + * Gets ip address with the given hostname. + * + * Parameters: + * hostname : host name as string type + * ipaddr : the pointer of ip address result + * + * Returned Value: + * On success, 0 is returned. On failure, a negative value is returned. + * + ****************************************************************************/ +int mdnsd_resolve_hostname(char *hostname, int *ipaddr) +{ + int result = -1; + struct timeval old_time, cur_time; + unsigned int time_diff; + int try_count; + int domain; - // combine service name - type_nlabel = create_nlabel(type); - inst_nlabel = create_nlabel(instance_name); - nlabel = join_nlabel(inst_nlabel, type_nlabel); +#ifndef MDNS_NO_RESPONDER_SUPPORT + if (g_svr == NULL) { + log_message(LOG_ERR, "mdnsd is not running.\n"); + goto out; + } +#endif - // create TXT record - if (txt && *txt) { - txt_e = rr_create(dup_nlabel(nlabel), RR_TXT); - rr_list_append(&service->entries, txt_e); - - // add TXTs - for (; *txt; txt++) - rr_add_txt(txt_e, *txt); + domain = check_mdns_domain(hostname); + if (domain == MDNS_DOMAIN_UNKNOWN) { + log_message(LOG_ERR, "hostname is invalid. hostname should be " +#if defined(CONFIG_NETUTILS_MDNS_XMDNS) + "%s or %s domain.\n", MDNS_SUFFIX_LOCAL, MDNS_SUFFIX_SITE); +#else + "%s domain.\n", MDNS_SUFFIX_LOCAL); +#endif + goto out; } - // create SRV record - assert(hostname || svr->hostname); // either one as target - target = hostname ? - create_nlabel(hostname) : - dup_nlabel(svr->hostname); + mdns_cmd_mutex_lock(); - srv_e = rr_create_srv(dup_nlabel(nlabel), port, target); - rr_list_append(&service->entries, srv_e); - - // create PTR record for type - ptr_e = rr_create_ptr(type_nlabel, srv_e); - - // create services PTR record for type - // this enables the type to show up as a "service" - bptr_e = rr_create_ptr(dup_nlabel(SERVICES_DNS_SD_NLABEL), ptr_e); - - // modify lists here - pthread_mutex_lock(&svr->data_lock); - - if (txt_e) - rr_group_add(&svr->group, txt_e); - rr_group_add(&svr->group, srv_e); - rr_group_add(&svr->group, ptr_e); - rr_group_add(&svr->group, bptr_e); - - // append PTR entry to announce list - rr_list_append(&svr->announce, ptr_e); - rr_list_append(&svr->services, ptr_e); - - pthread_mutex_unlock(&svr->data_lock); - - // don't free type_nlabel - it's with the PTR record - free(nlabel); - free(inst_nlabel); - - // notify server - write_pipe(svr->notify_pipe[1], ".", 1); - - return service; -} - -void mdns_service_destroy(struct mdns_service *srv) { - assert(srv != NULL); - rr_list_destroy(srv->entries, 0); - free(srv); -} - -struct mdnsd *mdnsd_start() { - pthread_t tid; - pthread_attr_t attr; - - struct mdnsd *server = malloc(sizeof(struct mdnsd)); - memset(server, 0, sizeof(struct mdnsd)); - - if (create_pipe(server->notify_pipe) != 0) { - log_message(LOG_ERR, "pipe(): %m\n"); - free(server); - return NULL; +#ifndef MDNS_NO_RESPONDER_SUPPORT + if (g_svr->stop_flag == 2) { + /* mdnsd main_loop has terminated by itself */ + log_message(LOG_ERR, "main_loop has been terminated. mdnsd will stop.\n"); + release_mdns_context_resource(); + goto out_with_mutex; + } +#else + if (init_mdns_context(domain) != 0) { + log_message(LOG_ERR, "init_mdns_context() failed.\n"); + goto out_with_mutex; } - server->sockfd = create_recv_sock(); - if (server->sockfd < 0) { - log_message(LOG_ERR, "unable to create recv socket"); - free(server); - return NULL; + pthread_mutex_lock(&g_svr->data_lock); + g_svr->c_status = CACHE_RESOLVE_HOSTNAME; + if (g_svr->c_filter) { + MDNS_FREE(g_svr->c_filter); + g_svr->c_filter = NULL; + } + g_svr->c_filter = MDNS_STRDUP(hostname); + pthread_mutex_unlock(&g_svr->data_lock); +#endif + + if (lookup_hostname_to_addr(g_svr, hostname, ipaddr) == 0) { + result = 0; +#ifndef MDNS_NO_RESPONDER_SUPPORT + goto out_with_mutex; +#else + goto out_with_context; +#endif } - pthread_mutex_init(&server->data_lock, NULL); + try_count = 0; + TIME_GET(old_time); + while (1) { + TIME_GET(cur_time); + time_diff = TIME_DIFF_USEC(old_time, cur_time); + if (time_diff > (MDNS_HOSTNAME_RESOLVER_TIMEOUT_MSEC * 1000)) { + break; + } - // init thread - pthread_attr_init(&attr); - pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); + if (try_count < MDNS_HOSTNAME_RESOLVER_MAX_TRY_COUNT) { + struct rr_entry *a_e = NULL; + struct rr_entry *aaaa_e = NULL; - if (pthread_create(&tid, &attr, (void *(*)(void *)) main_loop, (void *) server) != 0) { - pthread_mutex_destroy(&server->data_lock); - free(server); - return NULL; + a_e = qn_create(create_nlabel(hostname), RR_A, 0); + aaaa_e = qn_create(create_nlabel(hostname), RR_AAAA, 0); + + pthread_mutex_lock(&g_svr->data_lock); + + rr_list_append(&g_svr->query, a_e); + rr_list_append(&g_svr->query, aaaa_e); + + pthread_mutex_unlock(&g_svr->data_lock); + + request_sendmsg(g_svr); + + try_count++; + } + + usleep(MDNS_HOSTNAME_RESOLVER_WAIT_TIME_MSEC * 1000); + + if (lookup_hostname_to_addr(g_svr, hostname, ipaddr) == 0) { + result = 0; + break; + } } - return server; +#ifdef MDNS_NO_RESPONDER_SUPPORT +out_with_context: + pthread_mutex_lock(&g_svr->data_lock); + g_svr->c_status = CACHE_SLEEP; + if (g_svr->c_filter) { + MDNS_FREE(g_svr->c_filter); + g_svr->c_filter = NULL; + } + pthread_mutex_unlock(&g_svr->data_lock); + + if (destroy_mdns_context() != 0) { + log_message(LOG_ERR, "destroy_mdns_context() failed.\n"); + } +#endif + +out_with_mutex: + mdns_cmd_mutex_unlock(); + +out: + return result; } -void mdnsd_stop(struct mdnsd *s) { - assert(s != NULL); +/**************************************************************************** + * Name: mdnsd_discover_service + * + * Description: + * Discovers services with the given service type string + * + * Parameters: + * service_type : mdns service type string + * discover_time_msec : time in milliseconds for discovering service + * service_list : the array of service list + * num_of_services : number of services + * + * Returned Value: + * On success, 0 is returned. On failure, a negative value is returned. + * + ****************************************************************************/ +int mdnsd_discover_service(char *service_type, int discover_time_msec, struct mdns_service_info **service_list, int *num_of_services) +{ + int result = -1; + struct timeval old_time, cur_time; + unsigned int time_diff; + int try_count; + int domain; + char service_type_str[128]; - struct timeval tv = { - .tv_sec = 0, - .tv_usec = 500 * 1000, - }; + if (discover_time_msec <= 0 || discover_time_msec > MAX_SERVICE_DISCOVERY_TIME_MS) { + log_message(LOG_ERR, "discover_time_msec (%d) is invalid. (valid range : 0 < x <= %d)\n", discover_time_msec, MAX_SERVICE_DISCOVERY_TIME_MS); + goto out; + } - s->stop_flag = 1; - write_pipe(s->notify_pipe[1], ".", 1); + domain = check_mdns_domain(service_type); - while (s->stop_flag != 2) - select(0, NULL, NULL, NULL, &tv); +#ifndef MDNS_NO_RESPONDER_SUPPORT + if (g_svr == NULL) { + log_message(LOG_ERR, "mdnsd is not running.\n"); + goto out; + } - close_pipe(s->notify_pipe[0]); - close_pipe(s->notify_pipe[1]); + if (domain == MDNS_DOMAIN_UNKNOWN) { + switch (g_svr->domain) { + case MDNS_DOMAIN_LOCAL: + domain = MDNS_DOMAIN_LOCAL; + snprintf(service_type_str, sizeof(service_type_str), "%s%s", service_type, MDNS_SUFFIX_LOCAL); + break; +#if defined(CONFIG_NETUTILS_MDNS_XMDNS) + case MDNS_DOMAIN_SITE: + domain = MDNS_DOMAIN_SITE; + snprintf(service_type_str, sizeof(service_type_str), "%s%s", service_type, MDNS_SUFFIX_SITE); + break; +#endif + default: + log_message(LOG_ERR, "current mdns domain is invalid.\n"); + goto out; + } + } else { + snprintf(service_type_str, sizeof(service_type_str), "%s", service_type); + } - pthread_mutex_destroy(&s->data_lock); - rr_group_destroy(s->group); - rr_list_destroy(s->announce, 0); - rr_list_destroy(s->services, 0); +#else + if (domain == MDNS_DOMAIN_UNKNOWN) { + domain = MDNS_DOMAIN_LOCAL; + snprintf(service_type_str, sizeof(service_type_str), "%s%s", service_type, MDNS_SUFFIX_LOCAL); + } else { + snprintf(service_type_str, sizeof(service_type_str), "%s", service_type); + } +#endif - if (s->hostname) - free(s->hostname); + mdns_cmd_mutex_lock(); - free(s); +#ifndef MDNS_NO_RESPONDER_SUPPORT + if (g_svr->stop_flag == 2) { + /* mdnsd main_loop has terminated by itself */ + log_message(LOG_ERR, "main_loop has terminated. mdnsd will stop.\n"); + release_mdns_context_resource(); + goto out_with_mutex; + } +#else + if (init_mdns_context(domain) != 0) { + log_message(LOG_ERR, "init_mdns_context() failed.\n"); + goto out_with_mutex; + } +#endif + + pthread_mutex_lock(&g_svr->data_lock); + g_svr->c_status = CACHE_SERVICE_DISCOVERY; + if (g_svr->c_filter) { + MDNS_FREE(g_svr->c_filter); + g_svr->c_filter = NULL; + } + g_svr->c_filter = MDNS_STRDUP(service_type_str); + pthread_mutex_unlock(&g_svr->data_lock); + + /* query PTR for service discovery */ + struct rr_entry *ptr_e = NULL; + + try_count = 0; + TIME_GET(old_time); + while (1) { + TIME_GET(cur_time); + time_diff = TIME_DIFF_USEC(old_time, cur_time); + if (time_diff > (discover_time_msec * 1000)) { + break; + } + + if (try_count < MDNS_HOSTNAME_RESOLVER_MAX_TRY_COUNT) { + + ptr_e = qn_create(create_nlabel(service_type_str), RR_PTR, 0); + + pthread_mutex_lock(&g_svr->data_lock); + rr_list_append(&g_svr->query, ptr_e); + pthread_mutex_unlock(&g_svr->data_lock); + + request_sendmsg(g_svr); + + try_count++; + } + + usleep(MDNS_SERVICE_DISCOVERY_WAIT_TIME_MSEC * 1000); + } + + if (lookup_service(g_svr, service_type_str, g_service_list, num_of_services) == 0) { + *service_list = g_service_list; + result = 0; + } else { + *service_list = NULL; + } + + pthread_mutex_lock(&g_svr->data_lock); + if (g_svr->c_filter) { + MDNS_FREE(g_svr->c_filter); + g_svr->c_filter = NULL; + } +#ifndef MDNS_NO_RESPONDER_SUPPORT + g_svr->c_status = CACHE_NORMAL; +#else + g_svr->c_status = CACHE_SLEEP; +#endif + pthread_mutex_unlock(&g_svr->data_lock); + +#ifdef MDNS_NO_RESPONDER_SUPPORT + if (destroy_mdns_context() != 0) { + log_message(LOG_ERR, "destroy_mdns_context() failed.\n"); + } +#endif + +out_with_mutex: + mdns_cmd_mutex_unlock(); + +out: + return result; } diff --git a/mdnsd.h b/mdnsd.h index 99f1b86..b24ed9d 100644 --- a/mdnsd.h +++ b/mdnsd.h @@ -25,6 +25,7 @@ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ +/* APIs for Multicast DNS */ #ifndef __MDNSD_H__ #define __MDNSD_H__ @@ -34,12 +35,76 @@ struct mdnsd; struct mdns_service; -// starts a MDNS responder instance -// returns NULL if unsuccessful -struct mdnsd *mdnsd_start(); +#define MAX_NUMBER_OF_SERVICE_DISCOVERY_RESULT 10 +#define MAX_SERVICE_DISCOVERY_TIME_MS (60 * 1000) -// stops the given MDNS responder instance -void mdnsd_stop(struct mdnsd *s); +#define MDNS_HOSTNAME_RESOLVER_TIMEOUT_MSEC (3 * 1000) +#define MDNS_HOSTNAME_RESOLVER_MAX_TRY_COUNT 5 +#define MDNS_HOSTNAME_RESOLVER_WAIT_TIME_MSEC 250 + +#define MDNS_SERVICE_DISCOVERY_MAX_TRY_COUNT 5 +#define MDNS_SERVICE_DISCOVERY_WAIT_TIME_MSEC 250 + +/* Structure of MDNS service information */ +struct mdns_service_info { + char *type; + char *instance_name; + char *hostname; + unsigned int ipaddr; /* ipv4 */ + unsigned int port; +}; + +#ifdef __cplusplus +#define EXTERN extern "C" +extern "C" +{ +#else +#define EXTERN extern +#endif + +#ifndef MDNS_NO_RESPONDER_SUPPORT + +/** + * starts the MDNS daemon. + * + * [in] desired_hostname the desired host name as string type; if same name is in the network, an alternative name will be set as hostname. + * [in] netif_name network interface name as string type + * On success, 0 is returned. On failure, a negative value is returned. + * + */ +int mdnsd_start(const char *desired_hostname, const char *netif_name); + +/** + * mdnsd_stop() stops the MDNS daemon. + * + * On success, 0 is returned. On failure, a negative value is returned. + * + */ +int mdnsd_stop(void); + +/** + * mdnsd_get_hostname() gets the current host name as MDNS type. + * + * [out] hostname_result 32-bytes string buffer for the host name result + * On success, 0 is returned. On failure, a negative value is returned. + * + */ +int mdnsd_get_hostname(char *hostname_result); + +/** + * mdnsd_register_service() register a service to expose through mDNS-SD. + * + * [in] instance instance name to expose + * [in] type type of service. e.g. _http._tcp.local + * [in] port port to which the service is reachable + * [in] hostname if NULL, use the hostname configured when starting the daemon, + * or use this parameter otherwise + * [in] txt text records to add to the service announcement. Can be NULL. + * On success, 0 is returned. On failure, a negative errno value is returned. + * + */ +int mdnsd_register_service(const char *instance, const char *type, + uint16_t port, const char *hostname, const char *txt[]); // sets the hostname for the given MDNS responder instance void mdnsd_set_hostname(struct mdnsd *svr, const char *hostname, uint32_t ip); @@ -48,11 +113,41 @@ void mdnsd_set_hostname(struct mdnsd *svr, const char *hostname, uint32_t ip); void mdnsd_add_rr(struct mdnsd *svr, struct rr_entry *rr); // registers a service with the MDNS responder instance -struct mdns_service *mdnsd_register_svc(struct mdnsd *svr, const char *instance_name, - const char *type, uint16_t port, const char *hostname, const char *txt[]); +//struct mdns_service *mdnsd_register_svc(struct mdnsd *svr, const char *instance_name, +// const char *type, uint16_t port, const char *hostname, const char *txt[]); // destroys the mdns_service struct returned by mdnsd_register_svc() -void mdns_service_destroy(struct mdns_service *srv); +//void mdns_service_destroy(struct mdns_service *srv); + +#endif /* !defined MDNS_NO_RESPONDER_SUPPORT */ + +/** + * mdnsd_resolve_hostname() gets ip address with the given hostname. + * + * [in] hostname host name as string type + * [out] ipaddr the pointer of ip address result + * On success, 0 is returned. On failure, a negative value is returned. + * + */ +int mdnsd_resolve_hostname(char *hostname, int *ipaddr); + +/** + * mdnsd_discover_service() discovers services with the given service type string + * + * [in] service_type mdns service type string + * [in] discover_time_msec time in milliseconds for discovering service + * [out] service_list the array of service list + * [out] num_of_services number of services + * On success, 0 is returned. On failure, a negative value is returned. + * + */ +int mdnsd_discover_service(char *service_type, int discover_time_msec, struct mdns_service_info **service_list, int *num_of_services); -#endif/*!__MDNSD_H__*/ +#undef EXTERN +#ifdef __cplusplus +} +#endif + +#endif /*!__MDNSD_H__ */ + diff --git a/testmdnsd.c b/testmdnsd.c index 89652cc..554b0b4 100644 --- a/testmdnsd.c +++ b/testmdnsd.c @@ -25,6 +25,13 @@ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include #ifdef _WIN32 #include @@ -36,16 +43,15 @@ #include #endif -#include -#include -#include -#include -#include -#include - #include "mdns.h" #include "mdnsd.h" +#define HOSTFILE "/tmp/hosts" + +#if 0 +#include +#include + void background() { @@ -75,55 +81,287 @@ background() setsid(); } +#endif + +void freehostents( struct hostent * h) { + for (struct hostent *p = h; p->h_name; ++p) { + free(p->h_name); + free(p->h_addr_list); + } + free(h); +} + +struct hostent * add_host(struct hostent * hosts, const char * hostname, struct in_addr ip) { + struct hostent * p; + + int newname = 1; + for (p=hosts;p->h_name;++p) { + newname = 1; + if (p->h_length == 0 || + 0 == (newname = strcasecmp(p->h_name, hostname))) + break; + } + if (p->h_name) { + if (0 != newname) { + free(p->h_name); + p->h_name = strdup(hostname); + } + } else { + p->h_name = strdup(hostname); + (p+1)->h_name = 0; + } + p->h_aliases = 0; + p->h_addrtype = AF_INET; + p->h_length = sizeof(in_addr_t); + p->h_addr_list = (char **) realloc(p->h_addr_list, sizeof(struct in_addr)+2*sizeof(struct in_addr*)); + p->h_addr_list[0] = (char *)(p->h_addr_list + 2); + *(struct in_addr *)(p->h_addr_list[0]) = ip; + p->h_addr_list[1] = NULL; + return ++p; +} + +struct hostent * realloc_hosts(struct hostent * p, size_t n) { + struct hostent * new = (struct hostent *) realloc(p,n*sizeof(struct hostent)); + if (!new) { + fprintf(stderr, "Failed to allocate hostent: %s\n", strerror(errno)); + } + return new; +} + +struct hostent * read_hosts(unsigned int extra) { + FILE * hosts = fopen( HOSTFILE, "r"); + if (!hosts) { + fprintf(stderr, "Failed to open hosts file: %s\n", strerror(errno)); + return NULL; + } + size_t nhost = extra; + while (0 <= fscanf(hosts, "%*[^\n]") && !ferror(hosts)) { + if (0 <= fscanf(hosts,"%*c")) + ++nhost; + } + if (ferror(hosts) || -1 == fseek(hosts, 0L, SEEK_SET)) { + fprintf(stderr, "Failed to read hosts file: %s\n", strerror(errno)); + fclose(hosts); + return NULL; + } + + struct hostent * hostents = (struct hostent *) realloc_hosts(NULL,++nhost); + if (!hostents) { + fclose(hosts); + return NULL; + } else { + memset(hostents,0,nhost*sizeof(struct hostent)); + } + + char ip[256]; + char name[256]; + char fmt[32]; + + /* a format for [the beginning of] a /etc/hosts line */ + int n = 0; + if (snprintf( fmt, sizeof fmt - 1, "%%%zus %%%zus%%n%n", sizeof ip - 1, sizeof name - 1, &n) != n) { + fprintf(stderr, "Format length %d inadequate\n", n); + } + /* and for further hostnames */ + char * nfmt = strchr(fmt,' ')+1; + char * line = NULL; + size_t linesz = 0; + size_t nleft = nhost; + hostents->h_name = 0; + for (struct hostent * p = hostents;;) { + int ret = getline( &line, &linesz, hosts); + int pos = 0; + if (ret == -1) { + if (!feof(hosts)) { + fprintf(stderr, "Failure reading hosts file: %s\n", strerror(errno)); + freehostents(hostents); + hostents = NULL; + } + break; + } + /* skip initial space and any comment line */ + ret = sscanf( line, " %n", &pos ); + if (0 <= ret) { + int n = 0; + ret = sscanf( line+pos, "#%*[^\n]%n", &n); + if (n > 0) continue; + } + + if (0 <= ret) { + int n = 0; + ret = sscanf( line+pos, fmt, ip, name, &n); + // printf( "Read: %.255s\t%.32s\t%d\n", name, ip, ret); + pos += n; + } + if (ret == 2) { + struct in_addr it; + it.s_addr = inet_addr(ip); + do { + struct hostent * pp = add_host(p, name, it); + char * dot = strrchr(p->h_name, '.'); + if (dot && 0 == strcasecmp(dot, ".local")) + /* flag as expendable */ + p->h_length = 0; + p = pp; + + /* running out of space? try for more */ + if (--nleft < extra + 1) { + size_t n = 2*nhost; + struct hostent * new = (struct hostent *) realloc_hosts(hostents,n); + if (!new) { + free(line); + fclose(hosts); + free(hostents); + return NULL; + } + /* zero the new space and adjust counts and pointers */ + memset(new+nhost,0,(n-nhost)*sizeof(struct hostent)); + nleft += n - nhost; + nhost = n; + p += new - hostents; + hostents = new; + } + + /* allow for ip name [name ...] */ + int n = 0; + ret = sscanf( line+pos, " %n", &n); + pos += n; + /* skip comment */ + if (0 <= ret) { + n = 0; + ret = sscanf( line+pos, "#%*[^\n]%n", &n); + if (n > 0) break; + } + if (0 <= ret) { + n = 0; + ret = sscanf( line+pos, nfmt, name, &n); + pos += n; + } + } while (ret == 1); + p->h_name = 0; + } else if (ret >= 0) { + fprintf(stderr, "Unexpected format in hosts file; line was\n%s\n", line); + } + } + free(line); + fclose(hosts); + return hostents; +} + +int write_hosts(const struct hostent * hostents) { + int ret = -1; + FILE * hosts = fopen( HOSTFILE, "w"); + if (!hosts) { + fprintf(stderr, "Failed to open hosts file: %s\n", strerror(errno)); + return ret; + } + for (const struct hostent * p = hostents;p->h_name;++p) { + //printf( "writing %.255s\n", p->h_name); + if (p->h_length > 0) { + for (struct in_addr ** pa = (struct in_addr **)(p->h_addr_list); *pa; ++pa) { + ret = fprintf( hosts, "%s\t%s\n", inet_ntoa(**pa), p->h_name); + } + } + } + fclose(hosts); + return ret; +} + +void dump_hosts(const struct hostent * hostents) { + for (const struct hostent * p = hostents;p->h_name;++p) { + printf( "Host: %.255s\t%.32s\t%d\n", p->h_name, + inet_ntoa(*(struct in_addr *)(p->h_addr_list[0])), + p->h_length); + } +} int main(int argc, char **argv) { - char hostname[0x100], ifname[0x100]; - struct hostent *hp; + char hostname[0x100], ifname[0x120], fullname[0x108]; + struct in_addr saddr; + int notrunning = 1; if (gethostname(hostname, sizeof(hostname) - 1) == -1) { - printf("Couldn't retrieve humax hostname.\n"); + fprintf(stderr, "Couldn't retrieve humax hostname.\n"); return 1; } - if (!(hp = gethostbyname(hostname))) - { - printf("Couldn't retrieve humax IP address.\n"); - return 1; + int n = 0; + if (snprintf(fullname, sizeof fullname - 1, "%s.local%n", hostname, &n) != n || + (n = 0, sprintf(ifname, "Humax Fox T2 (%s) Web Interface%n", hostname, &n) != n)) { + fprintf( stderr, "Format length %d inadeqate\n", n); } - memmove((char *)&saddr.s_addr, (char *)hp->h_addr, - sizeof(saddr.s_addr)); - printf("Hostname: %s (%s)\n", hostname, inet_ntoa(saddr)); - - struct mdnsd *svr = mdnsd_start(); - if (svr == NULL) { - printf("mdnsd_start() error\n"); - return 1; - } - printf("Started MDNS Service\n"); - - mdnsd_set_hostname(svr, hostname, saddr.s_addr); - - sprintf(ifname, "Humax Fox T2 (%s) Web Interface", hostname); const char *txt[] = { "path=/", NULL }; - struct mdns_service *svc = mdnsd_register_svc( - svr, ifname, "_http._tcp.local", 80, - NULL, txt); - //mdns_service_destroy(svc); - printf("Registered name.\n"); + for (saddr.s_addr = 0;;sleep(61)) { + struct hostent *hp = gethostbyname(hostname); + char * ip_addr; + + if (!hp || hp->h_length != sizeof(saddr.s_addr)) + { + fprintf(stderr, "Couldn't retrieve humax IP address.\n"); + return 1; + } + + if (saddr.s_addr != *(in_addr_t *)(hp->h_addr_list[0])) { + if ((notrunning == 0) && (0 > mdnsd_stop())) { + fprintf(stderr, "mdnsd_stop() error\n"); + return 1; + } + + saddr.s_addr = *(in_addr_t *)(hp->h_addr_list[0]); - for (;;) - sleep(3600); + ip_addr = inet_ntoa(saddr); - // mdnsd_stop(svr); + printf("Hostname: %s (%s)\n", hostname, ip_addr); + + if (mdnsd_start(fullname, ip_addr) < 0) { + fprintf(stderr, "mdnsd_start() error\n"); + return 1; + } + notrunning = 0; + + if (0 <= mdnsd_register_service( + ifname, "_http._tcp.local", 80, + hostname, txt)) + printf("Registered name.\n"); + } + + int numserv = 0; + struct mdns_service_info * svcinfo; + + if (0 <= mdnsd_discover_service("_http._tcp.local", 5000, &svcinfo, &numserv)) { + + struct hostent * hosts = read_hosts(numserv); + if (!hosts) { + fprintf(stderr,"null hosts\n"); + return 1; + } + //dump_hosts(hosts); + struct hostent * p = hosts; + for (int i = 0; i < numserv; ++i) { + struct in_addr it; + it.s_addr = svcinfo[i].ipaddr; + printf("Host %d: %s (%s)\n", i, svcinfo[i].hostname, inet_ntoa(it)); + p = add_host(p, svcinfo[i].hostname, it); + } + p->h_name = 0; + //dump_hosts(hosts); + write_hosts(hosts); + freehostents(hosts); + } + } + + if ((notrunning == 0) && (0 > mdnsd_stop())) { + fprintf(stderr,"mdnsd_stop() error\n"); + } return 0; }