--- embedaddon/dnsmasq/contrib/lease-tools/dhcp_release6.c 2021/03/17 00:56:46 1.1.1.2 +++ embedaddon/dnsmasq/contrib/lease-tools/dhcp_release6.c 2023/09/27 11:02:07 1.1.1.3 @@ -318,6 +318,12 @@ void usage(const char* arg, FILE* stream) fprintf (stream, "Usage: %s %s\n", arg, usage_string); } +static void fail_fatal(const char *errstr, int exitcode) +{ + perror(errstr); + exit(exitcode); +} + int send_release_packet(const char* iface, struct dhcp6_packet* packet) { struct sockaddr_in6 server_addr, client_addr; @@ -343,18 +349,19 @@ int send_release_packet(const char* iface, struct dhcp client_addr.sin6_port = htons(DHCP6_CLIENT_PORT); client_addr.sin6_flowinfo = 0; client_addr.sin6_scope_id =0; - inet_pton(AF_INET6, "::", &client_addr.sin6_addr); - bind(sock, (struct sockaddr*)&client_addr, sizeof(struct sockaddr_in6)); - inet_pton(AF_INET6, DHCP6_MULTICAST_ADDRESS, &server_addr.sin6_addr); + if (inet_pton(AF_INET6, "::", &client_addr.sin6_addr) <= 0) + fail_fatal("inet_pton", 5); + if (bind(sock, (struct sockaddr*)&client_addr, sizeof(struct sockaddr_in6)) != 0) + perror("bind"); /* continue on bind error */ + if (inet_pton(AF_INET6, DHCP6_MULTICAST_ADDRESS, &server_addr.sin6_addr) <= 0) + fail_fatal("inet_pton", 5); server_addr.sin6_port = htons(DHCP6_SERVER_PORT); - int16_t recv_size = 0; + ssize_t recv_size = 0; + int result; for (i = 0; i < 5; i++) { if (sendto(sock, packet->buf, packet->len, 0, (struct sockaddr *)&server_addr, sizeof(server_addr)) < 0) - { - perror("sendto failed"); - exit(4); - } + fail_fatal("sendto failed", 4); recv_size = recvfrom(sock, response, sizeof(response), MSG_DONTWAIT, NULL, 0); if (recv_size == -1) @@ -367,16 +374,18 @@ int send_release_packet(const char* iface, struct dhcp else { perror("recvfrom"); + result = UNSPEC_FAIL; } } - - int16_t result = parse_packet(response, recv_size); - if (result == NOT_REPLY_CODE) + else { - sleep(1); - continue; + result = parse_packet(response, recv_size); + if (result == NOT_REPLY_CODE) + { + sleep(1); + continue; + } } - close(sock); return result; }