diff options
| -rw-r--r-- | checksum.c | 1 | ||||
| -rw-r--r-- | tcp.c | 118 |
2 files changed, 100 insertions, 19 deletions
@@ -503,7 +503,6 @@ uint16_t csum(const void *buf, size_t len, uint32_t init) * * Return: 16-bit folded, complemented checksum */ -/* cppcheck-suppress unusedFunction */ uint16_t csum_iov(const struct iovec *iov, size_t n, size_t offset, uint32_t init) { @@ -755,36 +755,106 @@ static void tcp_sock_set_bufsize(const struct ctx *c, int s) } /** - * tcp_update_check_tcp4() - Update TCP checksum from stored one + * tcp_update_check_tcp4() - Calculate TCP checksum for IPv4 * @iph: IPv4 header - * @bp: TCP header followed by TCP payload + * @iov: Pointer to the array of IO vectors + * @iov_cnt: Length of the array + * @l4offset: IPv4 payload offset in the iovec array */ static void tcp_update_check_tcp4(const struct iphdr *iph, - struct tcp_payload_t *bp) + const struct iovec *iov, int iov_cnt, + size_t l4offset) { uint16_t l4len = ntohs(iph->tot_len) - sizeof(struct iphdr); struct in_addr saddr = { .s_addr = iph->saddr }; struct in_addr daddr = { .s_addr = iph->daddr }; - uint32_t sum = proto_ipv4_header_psum(l4len, IPPROTO_TCP, saddr, daddr); + size_t check_ofs; + __sum16 *check; + int check_idx; + uint32_t sum; + char *ptr; + + sum = proto_ipv4_header_psum(l4len, IPPROTO_TCP, saddr, daddr); + + check_idx = iov_skip_bytes(iov, iov_cnt, + l4offset + offsetof(struct tcphdr, check), + &check_ofs); + + if (check_idx >= iov_cnt) { + err("TCP4 buffer is too small, iov size %zd, check offset %zd", + iov_size(iov, iov_cnt), + l4offset + offsetof(struct tcphdr, check)); + return; + } - bp->th.check = 0; - bp->th.check = csum(bp, l4len, sum); + if (check_ofs + sizeof(*check) > iov[check_idx].iov_len) { + err("TCP4 checksum field memory is not contiguous " + "check_ofs %zd check_idx %d iov_len %zd", + check_ofs, check_idx, iov[check_idx].iov_len); + return; + } + + ptr = (char *)iov[check_idx].iov_base + check_ofs; + if ((uintptr_t)ptr & (__alignof__(*check) - 1)) { + err("TCP4 checksum field is not correctly aligned in memory"); + return; + } + + check = (__sum16 *)ptr; + + *check = 0; + *check = csum_iov(iov, iov_cnt, l4offset, sum); } /** * tcp_update_check_tcp6() - Calculate TCP checksum for IPv6 * @ip6h: IPv6 header - * @bp: TCP header followed by TCP payload + * @iov: Pointer to the array of IO vectors + * @iov_cnt: Length of the array + * @l4offset: IPv6 payload offset in the iovec array */ static void tcp_update_check_tcp6(const struct ipv6hdr *ip6h, - struct tcp_payload_t *bp) + const struct iovec *iov, int iov_cnt, + size_t l4offset) { uint16_t l4len = ntohs(ip6h->payload_len); - uint32_t sum = proto_ipv6_header_psum(l4len, IPPROTO_TCP, - &ip6h->saddr, &ip6h->daddr); + size_t check_ofs; + __sum16 *check; + int check_idx; + uint32_t sum; + char *ptr; + + sum = proto_ipv6_header_psum(l4len, IPPROTO_TCP, &ip6h->saddr, + &ip6h->daddr); + + check_idx = iov_skip_bytes(iov, iov_cnt, + l4offset + offsetof(struct tcphdr, check), + &check_ofs); + + if (check_idx >= iov_cnt) { + err("TCP6 buffer is too small, iov size %zd, check offset %zd", + iov_size(iov, iov_cnt), + l4offset + offsetof(struct tcphdr, check)); + return; + } + + if (check_ofs + sizeof(*check) > iov[check_idx].iov_len) { + err("TCP6 checksum field memory is not contiguous " + "check_ofs %zd check_idx %d iov_len %zd", + check_ofs, check_idx, iov[check_idx].iov_len); + return; + } + + ptr = (char *)iov[check_idx].iov_base + check_ofs; + if ((uintptr_t)ptr & (__alignof__(*check) - 1)) { + err("TCP6 checksum field is not correctly aligned in memory"); + return; + } - bp->th.check = 0; - bp->th.check = csum(bp, l4len, sum); + check = (__sum16 *)ptr; + + *check = 0; + *check = csum_iov(iov, iov_cnt, l4offset, sum); } /** @@ -935,10 +1005,16 @@ static size_t tcp_fill_headers4(const struct tcp_tap_conn *conn, tcp_fill_header(&bp->th, conn, seq); - if (no_tcp_csum) + if (no_tcp_csum) { bp->th.check = 0; - else - tcp_update_check_tcp4(iph, bp); + } else { + const struct iovec iov = { + .iov_base = bp, + .iov_len = ntohs(iph->tot_len) - sizeof(struct iphdr), + }; + + tcp_update_check_tcp4(iph, &iov, 1, 0); + } tap_hdr_update(taph, l3len + sizeof(struct ethhdr)); @@ -980,10 +1056,16 @@ static size_t tcp_fill_headers6(const struct tcp_tap_conn *conn, tcp_fill_header(&bp->th, conn, seq); - if (no_tcp_csum) + if (no_tcp_csum) { bp->th.check = 0; - else - tcp_update_check_tcp6(ip6h, bp); + } else { + const struct iovec iov = { + .iov_base = bp, + .iov_len = ntohs(ip6h->payload_len) + }; + + tcp_update_check_tcp6(ip6h, &iov, 1, 0); + } tap_hdr_update(taph, l4len + sizeof(*ip6h) + sizeof(struct ethhdr)); |