tpws: support android versions 5+

tpws/Makefile

@@ -2,12 +2,17 @@ CC ?= gcc
 CFLAGS += -std=gnu99 -Os
 CFLAGS_BSD = -Wno-address-of-packed-member
 LIBS = -lz -lpthread
+LIBS_ANDROID = -lz
 SRC_FILES = *.c
+SRC_FILES_ANDROID = $(SRC_FILES) andr/*.c
 
 all: tpws
 
 tpws: $(SRC_FILES)
-	$(CC) -s $(CFLAGS) -o $@ $(SRC_FILES) $(LDFLAGS) $(LIBS)
+	$(CC) -s $(CFLAGS) -o tpws $(SRC_FILES) $(LDFLAGS) $(LIBS)
+
+android: $(SRC_FILES)
+	$(CC) -s $(CFLAGS) -o tpws $(SRC_FILES_ANDROID) $(LDFLAGS) $(LIBS_ANDROID)
 
 bsd: $(SRC_FILES)
 	$(CC) -s $(CFLAGS) $(CFLAGS_BSD) -Iepoll-shim/include -o tpws $(SRC_FILES) epoll-shim/src/*.c $(LDFLAGS) $(LIBS)

tpws/andr/_musl_license.txt

@@ -0,0 +1,26 @@
+Code in this dir is taken from musl libc to support old android versions <7.0
+
+musl as a whole is licensed under the following standard MIT license:
+
+----------------------------------------------------------------------
+Copyright © 2005-2020 Rich Felker, et al.
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+----------------------------------------------------------------------

tpws/andr/getifaddrs.c

@@ -0,0 +1,216 @@
+#define _GNU_SOURCE
+#include <errno.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <ifaddrs.h>
+#include <syscall.h>
+#include <net/if.h>
+#include <netinet/in.h>
+#include "netlink.h"
+
+#define IFADDRS_HASH_SIZE 64
+
+/* getifaddrs() reports hardware addresses with PF_PACKET that implies
+ * struct sockaddr_ll.  But e.g. Infiniband socket address length is
+ * longer than sockaddr_ll.ssl_addr[8] can hold. Use this hack struct
+ * to extend ssl_addr - callers should be able to still use it. */
+struct sockaddr_ll_hack {
+	unsigned short sll_family, sll_protocol;
+	int sll_ifindex;
+	unsigned short sll_hatype;
+	unsigned char sll_pkttype, sll_halen;
+	unsigned char sll_addr[24];
+};
+
+union sockany {
+	struct sockaddr sa;
+	struct sockaddr_ll_hack ll;
+	struct sockaddr_in v4;
+	struct sockaddr_in6 v6;
+};
+
+struct ifaddrs_storage {
+	struct ifaddrs ifa;
+	struct ifaddrs_storage *hash_next;
+	union sockany addr, netmask, ifu;
+	unsigned int index;
+	char name[IFNAMSIZ+1];
+};
+
+struct ifaddrs_ctx {
+	struct ifaddrs *first;
+	struct ifaddrs *last;
+	struct ifaddrs_storage *hash[IFADDRS_HASH_SIZE];
+};
+
+void freeifaddrs(struct ifaddrs *ifp)
+{
+	struct ifaddrs *n;
+	while (ifp) {
+		n = ifp->ifa_next;
+		free(ifp);
+		ifp = n;
+	}
+}
+
+static void copy_addr(struct sockaddr **r, int af, union sockany *sa, void *addr, size_t addrlen, int ifindex)
+{
+	uint8_t *dst;
+	int len;
+
+	switch (af) {
+	case AF_INET:
+		dst = (uint8_t*) &sa->v4.sin_addr;
+		len = 4;
+		break;
+	case AF_INET6:
+		dst = (uint8_t*) &sa->v6.sin6_addr;
+		len = 16;
+		if (IN6_IS_ADDR_LINKLOCAL(addr) || IN6_IS_ADDR_MC_LINKLOCAL(addr))
+			sa->v6.sin6_scope_id = ifindex;
+		break;
+	default:
+		return;
+	}
+	if (addrlen < len) return;
+	sa->sa.sa_family = af;
+	memcpy(dst, addr, len);
+	*r = &sa->sa;
+}
+
+static void gen_netmask(struct sockaddr **r, int af, union sockany *sa, int prefixlen)
+{
+	uint8_t addr[16] = {0};
+	int i;
+
+	if (prefixlen > 8*sizeof(addr)) prefixlen = 8*sizeof(addr);
+	i = prefixlen / 8;
+	memset(addr, 0xff, i);
+	if (i < sizeof(addr)) addr[i++] = 0xff << (8 - (prefixlen % 8));
+	copy_addr(r, af, sa, addr, sizeof(addr), 0);
+}
+
+static void copy_lladdr(struct sockaddr **r, union sockany *sa, void *addr, size_t addrlen, int ifindex, unsigned short hatype)
+{
+	if (addrlen > sizeof(sa->ll.sll_addr)) return;
+	sa->ll.sll_family = AF_PACKET;
+	sa->ll.sll_ifindex = ifindex;
+	sa->ll.sll_hatype = hatype;
+	sa->ll.sll_halen = addrlen;
+	memcpy(sa->ll.sll_addr, addr, addrlen);
+	*r = &sa->sa;
+}
+
+static int netlink_msg_to_ifaddr(void *pctx, struct nlmsghdr *h)
+{
+	struct ifaddrs_ctx *ctx = pctx;
+	struct ifaddrs_storage *ifs, *ifs0;
+	struct ifinfomsg *ifi = NLMSG_DATA(h);
+	struct ifaddrmsg *ifa = NLMSG_DATA(h);
+	struct rtattr *rta;
+	int stats_len = 0;
+
+	if (h->nlmsg_type == RTM_NEWLINK) {
+		for (rta = NLMSG_RTA(h, sizeof(*ifi)); NLMSG_RTAOK(rta, h); rta = RTA_NEXT(rta)) {
+			if (rta->rta_type != IFLA_STATS) continue;
+			stats_len = RTA_DATALEN(rta);
+			break;
+		}
+	} else {
+		for (ifs0 = ctx->hash[ifa->ifa_index % IFADDRS_HASH_SIZE]; ifs0; ifs0 = ifs0->hash_next)
+			if (ifs0->index == ifa->ifa_index)
+				break;
+		if (!ifs0) return 0;
+	}
+
+	ifs = calloc(1, sizeof(struct ifaddrs_storage) + stats_len);
+	if (ifs == 0) return -1;
+
+	if (h->nlmsg_type == RTM_NEWLINK) {
+		ifs->index = ifi->ifi_index;
+		ifs->ifa.ifa_flags = ifi->ifi_flags;
+
+		for (rta = NLMSG_RTA(h, sizeof(*ifi)); NLMSG_RTAOK(rta, h); rta = RTA_NEXT(rta)) {
+			switch (rta->rta_type) {
+			case IFLA_IFNAME:
+				if (RTA_DATALEN(rta) < sizeof(ifs->name)) {
+					memcpy(ifs->name, RTA_DATA(rta), RTA_DATALEN(rta));
+					ifs->ifa.ifa_name = ifs->name;
+				}
+				break;
+			case IFLA_ADDRESS:
+				copy_lladdr(&ifs->ifa.ifa_addr, &ifs->addr, RTA_DATA(rta), RTA_DATALEN(rta), ifi->ifi_index, ifi->ifi_type);
+				break;
+			case IFLA_BROADCAST:
+				copy_lladdr(&ifs->ifa.ifa_broadaddr, &ifs->ifu, RTA_DATA(rta), RTA_DATALEN(rta), ifi->ifi_index, ifi->ifi_type);
+				break;
+			case IFLA_STATS:
+				ifs->ifa.ifa_data = (void*)(ifs+1);
+				memcpy(ifs->ifa.ifa_data, RTA_DATA(rta), RTA_DATALEN(rta));
+				break;
+			}
+		}
+		if (ifs->ifa.ifa_name) {
+			unsigned int bucket = ifs->index % IFADDRS_HASH_SIZE;
+			ifs->hash_next = ctx->hash[bucket];
+			ctx->hash[bucket] = ifs;
+		}
+	} else {
+		ifs->ifa.ifa_name = ifs0->ifa.ifa_name;
+		ifs->ifa.ifa_flags = ifs0->ifa.ifa_flags;
+		for (rta = NLMSG_RTA(h, sizeof(*ifa)); NLMSG_RTAOK(rta, h); rta = RTA_NEXT(rta)) {
+			switch (rta->rta_type) {
+			case IFA_ADDRESS:
+				/* If ifa_addr is already set we, received an IFA_LOCAL before
+				 * so treat this as destination address */
+				if (ifs->ifa.ifa_addr)
+					copy_addr(&ifs->ifa.ifa_dstaddr, ifa->ifa_family, &ifs->ifu, RTA_DATA(rta), RTA_DATALEN(rta), ifa->ifa_index);
+				else
+					copy_addr(&ifs->ifa.ifa_addr, ifa->ifa_family, &ifs->addr, RTA_DATA(rta), RTA_DATALEN(rta), ifa->ifa_index);
+				break;
+			case IFA_BROADCAST:
+				copy_addr(&ifs->ifa.ifa_broadaddr, ifa->ifa_family, &ifs->ifu, RTA_DATA(rta), RTA_DATALEN(rta), ifa->ifa_index);
+				break;
+			case IFA_LOCAL:
+				/* If ifa_addr is set and we get IFA_LOCAL, assume we have
+				 * a point-to-point network. Move address to correct field. */
+				if (ifs->ifa.ifa_addr) {
+					ifs->ifu = ifs->addr;
+					ifs->ifa.ifa_dstaddr = &ifs->ifu.sa;
+					memset(&ifs->addr, 0, sizeof(ifs->addr));
+				}
+				copy_addr(&ifs->ifa.ifa_addr, ifa->ifa_family, &ifs->addr, RTA_DATA(rta), RTA_DATALEN(rta), ifa->ifa_index);
+				break;
+			case IFA_LABEL:
+				if (RTA_DATALEN(rta) < sizeof(ifs->name)) {
+					memcpy(ifs->name, RTA_DATA(rta), RTA_DATALEN(rta));
+					ifs->ifa.ifa_name = ifs->name;
+				}
+				break;
+			}
+		}
+		if (ifs->ifa.ifa_addr)
+			gen_netmask(&ifs->ifa.ifa_netmask, ifa->ifa_family, &ifs->netmask, ifa->ifa_prefixlen);
+	}
+
+	if (ifs->ifa.ifa_name) {
+		if (!ctx->first) ctx->first = &ifs->ifa;
+		if (ctx->last) ctx->last->ifa_next = &ifs->ifa;
+		ctx->last = &ifs->ifa;
+	} else {
+		free(ifs);
+	}
+	return 0;
+}
+
+int getifaddrs(struct ifaddrs **ifap)
+{
+	struct ifaddrs_ctx _ctx, *ctx = &_ctx;
+	int r;
+	memset(ctx, 0, sizeof *ctx);
+	r = __rtnetlink_enumerate(AF_UNSPEC, AF_UNSPEC, netlink_msg_to_ifaddr, ctx);
+	if (r == 0) *ifap = ctx->first;
+	else freeifaddrs(ctx->first);
+	return r;
+}

tpws/andr/ifaddrs.h

@@ -0,0 +1,8 @@
+#pragma once
+
+#include <ifaddrs.h>
+
+#if __ANDROID_API__ < 24
+void freeifaddrs(struct ifaddrs *);
+int getifaddrs(struct ifaddrs **);
+#endif

tpws/andr/netlink.c

@@ -0,0 +1,54 @@
+#include <errno.h>
+#include <string.h>
+#include <syscall.h>
+#include <sys/socket.h>
+#include <unistd.h>
+
+#include "netlink.h"
+
+static int __netlink_enumerate(int fd, unsigned int seq, int type, int af,
+	int (*cb)(void *ctx, struct nlmsghdr *h), void *ctx)
+{
+	struct nlmsghdr *h;
+	union {
+		uint8_t buf[8192];
+		struct {
+			struct nlmsghdr nlh;
+			struct rtgenmsg g;
+		} req;
+		struct nlmsghdr reply;
+	} u;
+	int r, ret;
+
+	memset(&u.req, 0, sizeof(u.req));
+	u.req.nlh.nlmsg_len = sizeof(u.req);
+	u.req.nlh.nlmsg_type = type;
+	u.req.nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST;
+	u.req.nlh.nlmsg_seq = seq;
+	u.req.g.rtgen_family = af;
+	r = send(fd, &u.req, sizeof(u.req), 0);
+	if (r < 0) return r;
+
+	while (1) {
+		r = recv(fd, u.buf, sizeof(u.buf), MSG_DONTWAIT);
+		if (r <= 0) return -1;
+		for (h = &u.reply; NLMSG_OK(h, (void*)&u.buf[r]); h = NLMSG_NEXT(h)) {
+			if (h->nlmsg_type == NLMSG_DONE) return 0;
+			if (h->nlmsg_type == NLMSG_ERROR) return -1;
+			ret = cb(ctx, h);
+			if (ret) return ret;
+		}
+	}
+}
+
+int __rtnetlink_enumerate(int link_af, int addr_af, int (*cb)(void *ctx, struct nlmsghdr *h), void *ctx)
+{
+	int fd, r;
+
+	fd = socket(PF_NETLINK, SOCK_RAW|SOCK_CLOEXEC, NETLINK_ROUTE);
+	if (fd < 0) return -1;
+	r = __netlink_enumerate(fd, 1, RTM_GETLINK, link_af, cb, ctx);
+	if (!r) r = __netlink_enumerate(fd, 2, RTM_GETADDR, addr_af, cb, ctx);
+	close(fd);
+	return r;
+}

tpws/andr/netlink.h

@@ -0,0 +1,94 @@
+#include <stdint.h>
+
+/* linux/netlink.h */
+
+#define NETLINK_ROUTE 0
+
+struct nlmsghdr {
+	uint32_t	nlmsg_len;
+	uint16_t	nlmsg_type;
+	uint16_t	nlmsg_flags;
+	uint32_t	nlmsg_seq;
+	uint32_t	nlmsg_pid;
+};
+
+#define NLM_F_REQUEST	1
+#define NLM_F_MULTI	2
+#define NLM_F_ACK	4
+
+#define NLM_F_ROOT	0x100
+#define NLM_F_MATCH	0x200
+#define NLM_F_ATOMIC	0x400
+#define NLM_F_DUMP	(NLM_F_ROOT|NLM_F_MATCH)
+
+#define NLMSG_NOOP	0x1
+#define NLMSG_ERROR	0x2
+#define NLMSG_DONE	0x3
+#define NLMSG_OVERRUN	0x4
+
+/* linux/rtnetlink.h */
+
+#define RTM_NEWLINK	16
+#define RTM_GETLINK	18
+#define RTM_NEWADDR	20
+#define RTM_GETADDR	22
+
+struct rtattr {
+	unsigned short	rta_len;
+	unsigned short	rta_type;
+};
+
+struct rtgenmsg {
+	unsigned char	rtgen_family;
+};
+
+struct ifinfomsg {
+	unsigned char	ifi_family;
+	unsigned char	__ifi_pad;
+	unsigned short	ifi_type;
+	int		ifi_index;
+	unsigned	ifi_flags;
+	unsigned	ifi_change;
+};
+
+/* linux/if_link.h */
+
+#define IFLA_ADDRESS	1
+#define IFLA_BROADCAST	2
+#define IFLA_IFNAME	3
+#define IFLA_STATS	7
+
+/* linux/if_addr.h */
+
+struct ifaddrmsg {
+	uint8_t		ifa_family;
+	uint8_t		ifa_prefixlen;
+	uint8_t		ifa_flags;
+	uint8_t		ifa_scope;
+	uint32_t	ifa_index;
+};
+
+#define IFA_ADDRESS	1
+#define IFA_LOCAL	2
+#define IFA_LABEL	3
+#define IFA_BROADCAST	4
+
+/* musl */
+
+#define NETLINK_ALIGN(len)	(((len)+3) & ~3)
+#define NLMSG_DATA(nlh)		((void*)((char*)(nlh)+sizeof(struct nlmsghdr)))
+#define NLMSG_DATALEN(nlh)	((nlh)->nlmsg_len-sizeof(struct nlmsghdr))
+#define NLMSG_DATAEND(nlh)	((char*)(nlh)+(nlh)->nlmsg_len)
+#define NLMSG_NEXT(nlh)		(struct nlmsghdr*)((char*)(nlh)+NETLINK_ALIGN((nlh)->nlmsg_len))
+#define NLMSG_OK(nlh,end)	((char*)(end)-(char*)(nlh) >= sizeof(struct nlmsghdr))
+
+#define RTA_DATA(rta)		((void*)((char*)(rta)+sizeof(struct rtattr)))
+#define RTA_DATALEN(rta)	((rta)->rta_len-sizeof(struct rtattr))
+#define RTA_DATAEND(rta)	((char*)(rta)+(rta)->rta_len)
+#define RTA_NEXT(rta)		(struct rtattr*)((char*)(rta)+NETLINK_ALIGN((rta)->rta_len))
+#define RTA_OK(rta,end)		((char*)(end)-(char*)(rta) >= sizeof(struct rtattr))
+
+#define NLMSG_RTA(nlh,len)	((void*)((char*)(nlh)+sizeof(struct nlmsghdr)+NETLINK_ALIGN(len)))
+#define NLMSG_RTAOK(rta,nlh)	RTA_OK(rta,NLMSG_DATAEND(nlh))
+
+int __rtnetlink_enumerate(int link_af, int addr_af, int (*cb)(void *ctx, struct nlmsghdr *h), void *ctx);

tpws/helpers.c

@@ -7,11 +7,16 @@
 #include <errno.h>
 #include <sys/socket.h>
 #include <arpa/inet.h>
-#include <ifaddrs.h>
 #include <time.h>
 #include <sys/stat.h>
 #include <libgen.h>
 
+#ifdef __ANDROID__
+#include "andr/ifaddrs.h"
+#else
+#include <ifaddrs.h>
+#endif
+
 #include "helpers.h"
 
 int unique_size_t(size_t *pu, int ct)

tpws/tpws.c

@@ -7,7 +7,6 @@
 #include <netinet/in.h>
 #include <netinet/ip.h>
 #include <net/if.h>
-#include <ifaddrs.h>
 #include <netdb.h>
 #include <unistd.h>
 #include <arpa/inet.h>
@@ -25,6 +24,12 @@
 #include <time.h>
 #include <syslog.h>
 
+#ifdef __ANDROID__
+#include "andr/ifaddrs.h"
+#else
+#include <ifaddrs.h>
+#endif
+
 #include "tpws.h"
 
 #ifdef BSD