Some rawsock changes

diff --git a/rawsock.c b/rawsock.c
index 500d3af6fa578fca82cbd3ebacca0bf81e9be009..b3d7056f689939860dfc85ee1cd6149c8b169865 100644 (file)
--- a/rawsock.c
+++ b/rawsock.c
@@ -3,6 +3,10 @@
 #include <stdio.h>
 #include <pcap.h>
 
+#ifndef MIN
+#define MIN(a, b) ((a) < (b) ? (a) : (b))
+#endif
+
 struct rawsock
 {
        pcap_t *pcap;
@@ -10,9 +14,9 @@ struct rawsock
        int fd;
 };
 
-struct rawsock *rawsock_create(const char *interface)
+struct rawsock *rawsock_create(const char *interface, uint16_t protocol)
 {
-       char errbuf[PCAP_ERRBUF_SIZE];
+       char buf[PCAP_ERRBUF_SIZE];
        struct bpf_program fp;
        struct rawsock *sock;
        int err;
@@ -23,16 +27,16 @@ struct rawsock *rawsock_create(const char *interface)
                return NULL;
        }
 
-       errbuf[0] = '\0';
+       buf[0] = '\0';
 
-       sock->pcap = pcap_open_live(interface, BUFSIZ, 1, 1, errbuf);
+       sock->pcap = pcap_open_live(interface, BUFSIZ, 1, 1, buf);
        if (!sock->pcap) {
-               fprintf(stderr, "pcap_open_live: %s\n", errbuf);
+               fprintf(stderr, "pcap_open_live: %s\n", buf);
                goto cleanup_malloc;
        }
 
-       if (*errbuf) {
-               fprintf(stderr, "Warning: %s.\n", errbuf);
+       if (*buf) {
+               fprintf(stderr, "Warning: %s.\n", buf);
        }
 
        if (pcap_datalink(sock->pcap) != DLT_EN10MB) {
@@ -40,8 +44,14 @@ struct rawsock *rawsock_create(const char *interface)
                goto cleanup_pcap;
        }
 
-       err = pcap_compile(sock->pcap, &fp, "ether proto 0x0912", 0,
-                       PCAP_NETMASK_UNKNOWN);
+       sock->fd = pcap_get_selectable_fd(sock->pcap);
+       if (sock->fd == -1) {
+               fprintf(stderr, "No selectable file descriptor available.\n");
+               goto cleanup_pcap;
+       }
+
+       snprintf(buf, sizeof(buf), "ether proto %04x", protocol);
+       err = pcap_compile(sock->pcap, &fp, buf, 0, PCAP_NETMASK_UNKNOWN);
        if (err) {
                pcap_perror(sock->pcap, "pcap_compile");
                goto cleanup_pcap;
@@ -52,12 +62,6 @@ struct rawsock *rawsock_create(const char *interface)
                goto cleanup_pcap;
        }
 
-       sock->fd = pcap_get_selectable_fd(sock->pcap);
-       if (sock->fd == -1) {
-               fprintf(stderr, "No selectable file descriptor available.\n");
-               goto cleanup_pcap;
-       }
-
        return sock;
 
 cleanup_pcap:
@@ -67,9 +71,10 @@ cleanup_malloc:
        return NULL;
 }
 
-int rawsock_recv(struct rawsock *sock, uint8_t **buffer, unsigned *size)
+ssize_t rawsock_recv(struct rawsock *sock, uint8_t *buf, size_t len)
 {
        struct pcap_pkthdr* hdr;
+       const u_char *capbuf;
        int status;
        fd_set fds;
 
@@ -86,39 +91,33 @@ int rawsock_recv(struct rawsock *sock, uint8_t **buffer, unsigned *size)
                }
        }
 
-       status = pcap_next_ex(sock->pcap, &hdr, (const u_char**)buffer);
+       status = pcap_next_ex(sock->pcap, &hdr, &capbuf);
        switch (status) {
                case 1:
-                       status = 0;
-                       *size = hdr->caplen;
-                       break;
+                       memcpy(buf, capbuf, MIN(len, hdr->caplen));
+                       return hdr->caplen;
                case 0:
-                       status = 1;
-                       break;
+                       return 0;
                case -1:
                        pcap_perror(sock->pcap, "pcap_next_ex");
-                       status = -1;
-                       break;
+                       return -1;
                default:
                        fprintf(stderr, "pcap_next_ex: returned %d.\n", status);
-                       status = -1;
-                       break;
+                       return -1;
        }
-
-       return status;
 }
 
-int rawsock_send(struct rawsock *sock, uint8_t *buffer, size_t size)
+int rawsock_send(struct rawsock *sock, uint8_t *buf, size_t len)
 {
 #if defined(_WIN32) || defined(_WIN64)
-       if (pcap_sendpacket(sock->pcap, buffer, size) == 0) {
+       if (pcap_sendpacket(sock->pcap, buf, len) == 0) {
                return 0;
        } else {
                pcap_perror(sock->pcap, "pcap_sendpacket");
                return -1;
        }
 #else
-       if (pcap_inject(sock->pcap, buffer, size) != size) {
+       if (pcap_inject(sock->pcap, buf, len) == len) {
                return 0;
        } else {
                pcap_perror(sock->pcap, "pcap_inject");

diff --git a/rawsock.h b/rawsock.h
index f0b7c08e89ced7aa0b8382442cf0fd0ad0871efd..f7b3d5b6537c2bd402a96003ad5588085201b6d9 100644 (file)
--- a/rawsock.h
+++ b/rawsock.h
@@ -2,8 +2,8 @@
 
 struct rawsock;
 
-struct rawsock *rawsock_create(const char *interface);
+struct rawsock *rawsock_create(const char *interface, uint16_t protocol);
 int rawsock_close(struct rawsock *sock);
-int rawsock_send(struct rawsock *sock, uint8_t *buffer, size_t size);
-int rawsock_recv(struct rawsock *sock, uint8_t **buffer, unsigned *size);
+int rawsock_send(struct rawsock *sock, uint8_t *buf, size_t len);
+ssize_t rawsock_recv(struct rawsock *sock, uint8_t *buf, size_t len);
 int rawsock_set_timeout(struct rawsock *sock, unsigned msec);