Merge "v5: remove unused checksum helper functions" into main am: 78dd121443

Original change: https://android-review.googlesource.com/c/platform/hardware/google/apf/+/2957573

Change-Id: I429af92ed56b52d3590ffce7682bca0f29ee9b47
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

4 files changed, 3 insertions, 177 deletions

diff --git a/apf_checksum.h b/apf_checksum.h
index 057f7af..2c5468e 100644
--- a/apf_checksum.h
+++ b/apf_checksum.h
@@ -15,80 +15,6 @@ static u16 fix_udp_csum(u16 csum) {
     return csum ? csum : 0xFFFF;
 }
 
-#ifndef DO_NOT_NEED_OLD_CHECKSUM_CODE
-/**
- * Calculate the ipv4 header and tcp/udp layer 4 checksums.
- * (assumes IPv4 checksum field is set to partial sum of ipv4 options [likely 0])
- * (assumes L4 checksum field is set to L4 payload length on input)
- * Warning: TCP/UDP L4 checksum corrupts packet iff ipv4 options are present.
- * Warning: first IPV4_HLEN + TCP_HLEN == 40 bytes of ip4_pkt must be writable!
- * Returns 6-bit DSCP value [0..63], garbage on parse error.
- */
-static int calc_ipv4_csum(u8* const ip4_pkt, const s32 len) {
-    store_be16(ip4_pkt + 10, calc_csum(0xFFFF, ip4_pkt, IPV4_HLEN));
-
-    u8 proto = ip4_pkt[9];
-    u16 csum = calc_csum(proto, ip4_pkt + 12, len - 12);
-    switch (proto) {
-      case IPPROTO_ICMP:
-        /* Note: for this to work, the icmpv4 checksum field must be prefilled
-         * with non-zero negative sum of proto (1) and src/dst ips, ie:
-         * 5 * 0xFFFF - 1 - (src >> 16) - (src & 0xFFFF) - (dst >> 16) - (dst & 0xFFFF)
-         */
-        store_be16(ip4_pkt + IPV4_HLEN + 2, csum);
-        break;
-      case IPPROTO_TCP:
-        store_be16(ip4_pkt + IPV4_HLEN + 16, csum);
-        break;
-      case IPPROTO_UDP:
-        store_be16(ip4_pkt + IPV4_HLEN + 6, fix_udp_csum(csum));
-        break;
-    }
-    return ip4_pkt[1] >> 2;  /* DSCP */
-}
-
-/**
- * Calculate the ipv6 icmp6/tcp/udp layer 4 checksums.
- * (assumes L4 checksum field is set to L4 payload length on input)
- * Warning: first IPV6_HLEN + TCP_HLEN == 60 bytes of ip6_pkt must be writable!
- * Returns 6-bit DSCP value [0..63], garbage on parse error.
- */
-static int calc_ipv6_csum(u8* const ip6_pkt, const s32 len) {
-    u8 proto = ip6_pkt[6];
-    u16 csum = calc_csum(proto, ip6_pkt + 8, len - 8);
-    switch (proto) {
-      case IPPROTO_ICMPV6:
-        store_be16(ip6_pkt + IPV6_HLEN + 2, csum);
-        break;
-      case IPPROTO_TCP:
-        store_be16(ip6_pkt + IPV6_HLEN + 16, csum);
-        break;
-      case IPPROTO_UDP:
-        store_be16(ip6_pkt + IPV6_HLEN + 6, fix_udp_csum(csum));
-        break;
-    }
-    return (read_be16(ip6_pkt) >> 6) & 0x3F;  /* DSCP */
-}
-
-/**
- * Calculate and store packet checksums and return dscp.
- *
- * @param pkt - pointer to the start of the ethernet header of the packet.
- *     WARNING: first ETHER_HLEN + max(IPV{4,6}_HLEN) + TCP_HLEN = 74 bytes
- *              of buffer pointed to my 'pkt' pointer *MUST* be writable.
- * @param len - length of the packet.
- *
- * @return 6-bit DSCP value [0..63], garbage on parse error.
- */
-int calculate_checksum_and_return_dscp(u8* const pkt, const s32 len) {
-    switch (read_be16(pkt + 12)) {  /* ethertype */
-      case ETH_P_IP:   return calc_ipv4_csum(pkt + ETH_HLEN, len - ETH_HLEN);
-      case ETH_P_IPV6: return calc_ipv6_csum(pkt + ETH_HLEN, len - ETH_HLEN);
-      default: return 0;
-    }
-}
-#endif
-
 /**
  * Calculate and store packet checksums and return dscp.
  *
diff --git a/apf_checksum_test.cc b/apf_checksum_test.cc
index 78c87cb..9fe172d 100644
--- a/apf_checksum_test.cc
+++ b/apf_checksum_test.cc
@@ -50,21 +50,11 @@ TEST(ApfChecksumTest, CalcIPv4UDPChecksum) {
         0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x01, 0x62, 0x05, 0x6c, 0x6f, 0x63, 0x61, 0x6c, 0x00, 0x00,
         0x01, 0x80, 0x01, 0x00, 0x00, 0x00, 0x78, 0x00, 0x04, 0xc0, 0xa8, 0x01, 0x09,
     }};
-    // Set the UDP checksum to UDP payload size
-    ether_ipv4_udp_pkt.pkt.udphdr.check = htons(sizeof(ether_ipv4_udp_pkt) - IPV4_HLEN - ETH_HLEN);
-    uint8_t dscp = calculate_checksum_and_return_dscp((uint8_t *)&ether_ipv4_udp_pkt, sizeof(ether_ipv4_udp_pkt));
-    EXPECT_EQ(dscp, 1);
-    // Verify IPv4 header checksum
-    EXPECT_EQ(read_be16((uint8_t *)&ether_ipv4_udp_pkt.pkt.iphdr.check), 0x9535);
-
-    // verify UDP checksum
-    EXPECT_EQ(read_be16((uint8_t *)&ether_ipv4_udp_pkt.pkt.udphdr.check), 0xa73d);
-
     // Reset IPv4 header checksum to 0
     ether_ipv4_udp_pkt.pkt.iphdr.check = 0;
     // Set the UDP checksum to UDP payload size
     ether_ipv4_udp_pkt.pkt.udphdr.check = htons(sizeof(ether_ipv4_udp_pkt) - IPV4_HLEN - ETH_HLEN);
-    dscp = csum_and_return_dscp((uint8_t *)&ether_ipv4_udp_pkt, sizeof(ether_ipv4_udp_pkt),
+    uint8_t dscp = csum_and_return_dscp((uint8_t *)&ether_ipv4_udp_pkt, sizeof(ether_ipv4_udp_pkt),
                                 ETH_HLEN /* ip_ofs */, IPPROTO_UDP /* partial_csum */,
                                 ETH_HLEN + offsetof(iphdr, saddr) /* csum_start */,
                                 ETH_HLEN + IPV4_HLEN + offsetof(udphdr, check) /* csum_ofs */,
@@ -105,14 +95,7 @@ TEST(ApfChecksumTest, CalcIPv6UDPChecksum) {
     }};
     // Set the UDP checksum to UDP payload size
     ether_ipv6_udp_pkt.pkt.udphdr.check = htons(sizeof(ether_ipv6_udp_pkt) - IPV6_HLEN - ETH_HLEN);
-    uint8_t dscp = calculate_checksum_and_return_dscp((uint8_t *)&ether_ipv6_udp_pkt, sizeof(ether_ipv6_udp_pkt));
-    EXPECT_EQ(dscp, 6);
-    // verify UDP checksum
-    EXPECT_EQ(read_be16((uint8_t *)&ether_ipv6_udp_pkt.pkt.udphdr.check), 0x1cbd);
-
-    // Set the UDP checksum to UDP payload size
-    ether_ipv6_udp_pkt.pkt.udphdr.check = htons(sizeof(ether_ipv6_udp_pkt) - IPV6_HLEN - ETH_HLEN);
-    dscp = csum_and_return_dscp((uint8_t *)&ether_ipv6_udp_pkt, sizeof(ether_ipv6_udp_pkt),
+    uint8_t dscp = csum_and_return_dscp((uint8_t *)&ether_ipv6_udp_pkt, sizeof(ether_ipv6_udp_pkt),
                                 ETH_HLEN /* ip_ofs */, IPPROTO_UDP /* partial_csum */,
                                 ETH_HLEN + offsetof(ipv6hdr, saddr) /* csum_start */,
                                 ETH_HLEN + IPV6_HLEN + offsetof(udphdr, check) /* csum_ofs */,
@@ -150,14 +133,7 @@ TEST(ApfChecksumTest, CalcICMPv6Checksum) {
     }};
     // Set the ICMPv6 checksum to ICMPv6 payload size
     ether_ipv6_icmp6_pkt.pkt.icmp6hdr.icmp6_cksum = htons(sizeof(ether_ipv6_icmp6_pkt) - IPV6_HLEN - ETH_HLEN);
-    uint8_t dscp = calculate_checksum_and_return_dscp((uint8_t *)&ether_ipv6_icmp6_pkt, sizeof(ether_ipv6_icmp6_pkt));
-    EXPECT_EQ(dscp, 6);
-    // verify layer 4 checksum
-    EXPECT_EQ(read_be16((uint8_t *)&ether_ipv6_icmp6_pkt.pkt.icmp6hdr.icmp6_cksum), 0x8a09);
-
-    // Set the ICMPv6 checksum to ICMPv6 payload size
-    ether_ipv6_icmp6_pkt.pkt.icmp6hdr.icmp6_cksum = htons(sizeof(ether_ipv6_icmp6_pkt) - IPV6_HLEN - ETH_HLEN);
-    dscp = csum_and_return_dscp((uint8_t *)&ether_ipv6_icmp6_pkt, sizeof(ether_ipv6_icmp6_pkt),
+    uint8_t dscp = csum_and_return_dscp((uint8_t *)&ether_ipv6_icmp6_pkt, sizeof(ether_ipv6_icmp6_pkt),
                                 ETH_HLEN /* ip_ofs */, IPPROTO_ICMPV6 /* partial_csum */,
                                 ETH_HLEN + offsetof(ipv6hdr, saddr) /* csum_start */,
                                 ETH_HLEN + IPV6_HLEN + offsetof(icmp6hdr, icmp6_cksum) /* csum_ofs */,
diff --git a/v5/apf_interpreter.c b/v5/apf_interpreter.c
index b297be9..b546f2a 100644
--- a/v5/apf_interpreter.c
+++ b/v5/apf_interpreter.c
@@ -26,7 +26,6 @@
 
 typedef enum { false, true } bool;
 
-#define DO_NOT_NEED_OLD_CHECKSUM_CODE
 /* Begin include of apf_defs.h */
 typedef int8_t s8;
 typedef int16_t s16;
@@ -496,80 +495,6 @@ static u16 fix_udp_csum(u16 csum) {
     return csum ? csum : 0xFFFF;
 }
 
-#ifndef DO_NOT_NEED_OLD_CHECKSUM_CODE
-/**
- * Calculate the ipv4 header and tcp/udp layer 4 checksums.
- * (assumes IPv4 checksum field is set to partial sum of ipv4 options [likely 0])
- * (assumes L4 checksum field is set to L4 payload length on input)
- * Warning: TCP/UDP L4 checksum corrupts packet iff ipv4 options are present.
- * Warning: first IPV4_HLEN + TCP_HLEN == 40 bytes of ip4_pkt must be writable!
- * Returns 6-bit DSCP value [0..63], garbage on parse error.
- */
-static int calc_ipv4_csum(u8* const ip4_pkt, const s32 len) {
-    store_be16(ip4_pkt + 10, calc_csum(0xFFFF, ip4_pkt, IPV4_HLEN));
-
-    u8 proto = ip4_pkt[9];
-    u16 csum = calc_csum(proto, ip4_pkt + 12, len - 12);
-    switch (proto) {
-      case IPPROTO_ICMP:
-        /* Note: for this to work, the icmpv4 checksum field must be prefilled
-         * with non-zero negative sum of proto (1) and src/dst ips, ie:
-         * 5 * 0xFFFF - 1 - (src >> 16) - (src & 0xFFFF) - (dst >> 16) - (dst & 0xFFFF)
-         */
-        store_be16(ip4_pkt + IPV4_HLEN + 2, csum);
-        break;
-      case IPPROTO_TCP:
-        store_be16(ip4_pkt + IPV4_HLEN + 16, csum);
-        break;
-      case IPPROTO_UDP:
-        store_be16(ip4_pkt + IPV4_HLEN + 6, fix_udp_csum(csum));
-        break;
-    }
-    return ip4_pkt[1] >> 2;  /* DSCP */
-}
-
-/**
- * Calculate the ipv6 icmp6/tcp/udp layer 4 checksums.
- * (assumes L4 checksum field is set to L4 payload length on input)
- * Warning: first IPV6_HLEN + TCP_HLEN == 60 bytes of ip6_pkt must be writable!
- * Returns 6-bit DSCP value [0..63], garbage on parse error.
- */
-static int calc_ipv6_csum(u8* const ip6_pkt, const s32 len) {
-    u8 proto = ip6_pkt[6];
-    u16 csum = calc_csum(proto, ip6_pkt + 8, len - 8);
-    switch (proto) {
-      case IPPROTO_ICMPV6:
-        store_be16(ip6_pkt + IPV6_HLEN + 2, csum);
-        break;
-      case IPPROTO_TCP:
-        store_be16(ip6_pkt + IPV6_HLEN + 16, csum);
-        break;
-      case IPPROTO_UDP:
-        store_be16(ip6_pkt + IPV6_HLEN + 6, fix_udp_csum(csum));
-        break;
-    }
-    return (read_be16(ip6_pkt) >> 6) & 0x3F;  /* DSCP */
-}
-
-/**
- * Calculate and store packet checksums and return dscp.
- *
- * @param pkt - pointer to the start of the ethernet header of the packet.
- *     WARNING: first ETHER_HLEN + max(IPV{4,6}_HLEN) + TCP_HLEN = 74 bytes
- *              of buffer pointed to my 'pkt' pointer *MUST* be writable.
- * @param len - length of the packet.
- *
- * @return 6-bit DSCP value [0..63], garbage on parse error.
- */
-int calculate_checksum_and_return_dscp(u8* const pkt, const s32 len) {
-    switch (read_be16(pkt + 12)) {  /* ethertype */
-      case ETH_P_IP:   return calc_ipv4_csum(pkt + ETH_HLEN, len - ETH_HLEN);
-      case ETH_P_IPV6: return calc_ipv6_csum(pkt + ETH_HLEN, len - ETH_HLEN);
-      default: return 0;
-    }
-}
-#endif
-
 /**
  * Calculate and store packet checksums and return dscp.
  *
diff --git a/v5/apf_interpreter_source.c b/v5/apf_interpreter_source.c
index f120b1f..810e543 100644
--- a/v5/apf_interpreter_source.c
+++ b/v5/apf_interpreter_source.c
@@ -26,7 +26,6 @@
 
 typedef enum { false, true } bool;
 
-#define DO_NOT_NEED_OLD_CHECKSUM_CODE
 #include "apf_defs.h"
 #include "apf.h"
 #include "apf_utils.h"