From 781164e25bdf3e99233ab585f02c72525cfb79c5 Mon Sep 17 00:00:00 2001 From: David Gibson Date: Thu, 18 Jul 2024 15:26:41 +1000 Subject: [PATCH] flow: Helper to create sockets based on flowside We have upcoming use cases where it's useful to create new bound socket based on information from the flow table. Add flowside_sock_l4() to do this for either PIF_HOST or PIF_SPLICE sockets. Signed-off-by: David Gibson Signed-off-by: Stefano Brivio --- flow.c | 93 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ flow.h | 3 ++ util.c | 6 ++-- util.h | 3 ++ 4 files changed, 102 insertions(+), 3 deletions(-) diff --git a/flow.c b/flow.c index 8eea861..6ba8a62 100644 --- a/flow.c +++ b/flow.c @@ -5,9 +5,11 @@ * Tracking for logical "flows" of packets. */ +#include #include #include #include +#include #include #include "util.h" @@ -143,6 +145,97 @@ static void flowside_from_af(struct flowside *side, sa_family_t af, side->eport = eport; } +/** + * struct flowside_sock_args - Parameters for flowside_sock_splice() + * @c: Execution context + * @fd: Filled in with new socket fd + * @err: Filled in with errno if something failed + * @type: Socket epoll type + * @sa: Socket address + * @sl: Length of @sa + * @data: epoll reference data + */ +struct flowside_sock_args { + const struct ctx *c; + int fd; + int err; + enum epoll_type type; + const struct sockaddr *sa; + socklen_t sl; + const char *path; + uint32_t data; +}; + +/** flowside_sock_splice() - Create and bind socket for PIF_SPLICE based on flowside + * @arg: Argument as a struct flowside_sock_args + * + * Return: 0 + */ +static int flowside_sock_splice(void *arg) +{ + struct flowside_sock_args *a = arg; + + ns_enter(a->c); + + a->fd = sock_l4_sa(a->c, a->type, a->sa, a->sl, NULL, + a->sa->sa_family == AF_INET6, a->data); + a->err = errno; + + return 0; +} + +/** flowside_sock_l4() - Create and bind socket based on flowside + * @c: Execution context + * @type: Socket epoll type + * @pif: Interface for this socket + * @tgt: Target flowside + * @data: epoll reference portion for protocol handlers + * + * Return: socket fd of protocol @proto bound to the forwarding address and port + * from @tgt (if specified). + */ +/* cppcheck-suppress unusedFunction */ +int flowside_sock_l4(const struct ctx *c, enum epoll_type type, uint8_t pif, + const struct flowside *tgt, uint32_t data) +{ + const char *ifname = NULL; + union sockaddr_inany sa; + socklen_t sl; + + ASSERT(pif_is_socket(pif)); + + pif_sockaddr(c, &sa, &sl, pif, &tgt->faddr, tgt->fport); + + switch (pif) { + case PIF_HOST: + if (inany_is_loopback(&tgt->faddr)) + ifname = NULL; + else if (sa.sa_family == AF_INET) + ifname = c->ip4.ifname_out; + else if (sa.sa_family == AF_INET6) + ifname = c->ip6.ifname_out; + + return sock_l4_sa(c, type, &sa, sl, ifname, + sa.sa_family == AF_INET6, data); + + case PIF_SPLICE: { + struct flowside_sock_args args = { + .c = c, .type = type, + .sa = &sa.sa, .sl = sl, .data = data, + }; + NS_CALL(flowside_sock_splice, &args); + errno = args.err; + return args.fd; + } + + default: + /* If we add new socket pifs, they'll need to be implemented + * here + */ + ASSERT(0); + } +} + /** flow_log_ - Log flow-related message * @f: flow the message is related to * @pri: Log priority diff --git a/flow.h b/flow.h index e3a778a..bf6b845 100644 --- a/flow.h +++ b/flow.h @@ -164,6 +164,9 @@ static inline bool flowside_eq(const struct flowside *left, left->fport == right->fport; } +int flowside_sock_l4(const struct ctx *c, enum epoll_type type, uint8_t pif, + const struct flowside *tgt, uint32_t data); + /** * struct flow_common - Common fields for packet flows * @state: State of the flow table entry diff --git a/util.c b/util.c index 1569f1c..6b51fc5 100644 --- a/util.c +++ b/util.c @@ -45,9 +45,9 @@ * * Return: newly created socket, negative error code on failure */ -static int sock_l4_sa(const struct ctx *c, enum epoll_type type, - const void *sa, socklen_t sl, - const char *ifname, bool v6only, uint32_t data) +int sock_l4_sa(const struct ctx *c, enum epoll_type type, + const void *sa, socklen_t sl, + const char *ifname, bool v6only, uint32_t data) { sa_family_t af = ((const struct sockaddr *)sa)->sa_family; union epoll_ref ref = { .type = type, .data = data }; diff --git a/util.h b/util.h index 1d479dd..826614c 100644 --- a/util.h +++ b/util.h @@ -144,6 +144,9 @@ struct ctx; /* cppcheck-suppress funcArgNamesDifferent */ __attribute__ ((weak)) int ffsl(long int i) { return __builtin_ffsl(i); } +int sock_l4_sa(const struct ctx *c, enum epoll_type type, + const void *sa, socklen_t sl, + const char *ifname, bool v6only, uint32_t data); int sock_l4(const struct ctx *c, sa_family_t af, enum epoll_type type, const void *bind_addr, const char *ifname, uint16_t port, uint32_t data);