From: Gerrit Renker Date: Tue, 14 Nov 2006 14:48:10 +0000 (-0200) Subject: [DCCP]: Make feature negotiation more readable X-Git-Tag: v2.6.20-rc1~34^2~40^2~379 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c02fdc0e81e9c735d8d895af1e201b235df326d8;p=linux-2.6 [DCCP]: Make feature negotiation more readable This patch replaces cryptic feature negotiation messages of type Oct 31 15:42:20 kernel: dccp_feat_change: feat change type=32 feat=1 Oct 31 15:42:21 kernel: dccp_feat_change: feat change type=34 feat=1 Oct 31 15:42:21 kernel: dccp_feat_change: feat change type=32 feat=5 into ones of type: Nov 2 13:54:45 kernel: dccp_feat_change: ChangeL(CCID (1), 3) Nov 2 13:54:45 kernel: dccp_feat_change: ChangeR(CCID (1), 3) Nov 2 13:54:45 kernel: dccp_feat_change: ChangeL(Ack Ratio (5), 2) Also, * completed the feature number list wrt RFC 4340 sec. 6.4 * annotating which ones have been implemented so far * implemented rudimentary sanity checking in feat.c (FIXMEs) * some minor fixes Commiter note: uninlined dccp_feat_name and dccp_feat_typename, for consistency with dccp_{state,packet}_name, that, BTW, should be compiled only if CONFIG_IP_DCCP_DEBUG is selected, leaving this to another cset tho. Also shortened dccp_feat_negotiation_debug to dccp_feat_debug. Signed-off-by: Gerrit Renker Signed-off-by: Arnaldo Carvalho de Melo --- diff --git a/include/linux/dccp.h b/include/linux/dccp.h index 0502dfa7f3..696319ee2d 100644 --- a/include/linux/dccp.h +++ b/include/linux/dccp.h @@ -175,18 +175,21 @@ enum { DCCPC_CCID3 = 3, }; -/* DCCP features */ -enum { - DCCPF_RESERVED = 0, - DCCPF_CCID = 1, - DCCPF_SEQUENCE_WINDOW = 3, - DCCPF_ACK_RATIO = 5, - DCCPF_SEND_ACK_VECTOR = 6, - DCCPF_SEND_NDP_COUNT = 7, +/* DCCP features (RFC 4340 section 6.4) */ + enum { + DCCPF_RESERVED = 0, + DCCPF_CCID = 1, + DCCPF_SHORT_SEQNOS = 2, /* XXX: not yet implemented */ + DCCPF_SEQUENCE_WINDOW = 3, + DCCPF_ECN_INCAPABLE = 4, /* XXX: not yet implemented */ + DCCPF_ACK_RATIO = 5, + DCCPF_SEND_ACK_VECTOR = 6, + DCCPF_SEND_NDP_COUNT = 7, DCCPF_MIN_CSUM_COVER = 8, - /* 10-127 reserved */ - DCCPF_MIN_CCID_SPECIFIC = 128, - DCCPF_MAX_CCID_SPECIFIC = 255, + DCCPF_DATA_CHECKSUM = 9, /* XXX: not yet implemented */ + /* 10-127 reserved */ + DCCPF_MIN_CCID_SPECIFIC = 128, + DCCPF_MAX_CCID_SPECIFIC = 255, }; /* this structure is argument to DCCP_SOCKOPT_CHANGE_X */ diff --git a/net/dccp/feat.c b/net/dccp/feat.c index a1b0682ee7..12cde2f2f1 100644 --- a/net/dccp/feat.c +++ b/net/dccp/feat.c @@ -12,7 +12,6 @@ #include -#include "dccp.h" #include "ccid.h" #include "feat.h" @@ -23,9 +22,17 @@ int dccp_feat_change(struct dccp_minisock *dmsk, u8 type, u8 feature, { struct dccp_opt_pend *opt; - dccp_pr_debug("feat change type=%d feat=%d\n", type, feature); + dccp_feat_debug(type, feature, *val); - /* XXX sanity check feat change request */ + if (!dccp_feat_is_valid_type(type)) { + pr_info("option type %d invalid in negotiation\n", type); + return 1; + } + if (!dccp_feat_is_valid_length(type, feature, len)) { + pr_info("invalid length %d\n", len); + return 1; + } + /* XXX add further sanity checks */ /* check if that feature is already being negotiated */ list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) { @@ -95,14 +102,14 @@ static int dccp_feat_update_ccid(struct sock *sk, u8 type, u8 new_ccid_nr) /* XXX taking only u8 vals */ static int dccp_feat_update(struct sock *sk, u8 type, u8 feat, u8 val) { - dccp_pr_debug("changing [%d] feat %d to %d\n", type, feat, val); + dccp_feat_debug(type, feat, val); switch (feat) { case DCCPF_CCID: return dccp_feat_update_ccid(sk, type, val); default: - dccp_pr_debug("IMPLEMENT changing [%d] feat %d to %d\n", - type, feat, val); + dccp_pr_debug("UNIMPLEMENTED: %s(%d, ...)\n", + dccp_feat_typename(type), feat); break; } return 0; @@ -265,10 +272,10 @@ static int dccp_feat_nn(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len) u8 *copy; int rc; - /* NN features must be change L */ - if (type == DCCPO_CHANGE_R) { - dccp_pr_debug("received CHANGE_R %d for NN feat %d\n", - type, feature); + /* NN features must be Change L (sec. 6.3.2) */ + if (type != DCCPO_CHANGE_L) { + dccp_pr_debug("received %s for NN feature %d\n", + dccp_feat_typename(type), feature); return -EFAULT; } @@ -299,7 +306,8 @@ static int dccp_feat_nn(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len) return rc; } - dccp_pr_debug("Confirming NN feature %d (val=%d)\n", feature, *copy); + dccp_feat_debug(type, feature, *copy); + list_add_tail(&opt->dccpop_node, &dmsk->dccpms_conf); return 0; @@ -318,14 +326,19 @@ static void dccp_feat_empty_confirm(struct dccp_minisock *dmsk, return; } - opt->dccpop_type = type == DCCPO_CHANGE_L ? DCCPO_CONFIRM_R : - DCCPO_CONFIRM_L; + switch (type) { + case DCCPO_CHANGE_L: opt->dccpop_type = DCCPO_CONFIRM_R; break; + case DCCPO_CHANGE_R: opt->dccpop_type = DCCPO_CONFIRM_L; break; + default: pr_info("invalid type %d\n", type); return; + + } opt->dccpop_feat = feature; opt->dccpop_val = NULL; opt->dccpop_len = 0; /* change feature */ - dccp_pr_debug("Empty confirm feature %d type %d\n", feature, type); + dccp_pr_debug("Empty %s(%d)\n", dccp_feat_typename(type), feature); + list_add_tail(&opt->dccpop_node, &dmsk->dccpms_conf); } @@ -359,7 +372,7 @@ int dccp_feat_change_recv(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len) { int rc; - dccp_pr_debug("got feat change type=%d feat=%d\n", type, feature); + dccp_feat_debug(type, feature, *val); /* figure out if it's SP or NN feature */ switch (feature) { @@ -375,6 +388,8 @@ int dccp_feat_change_recv(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len) /* XXX implement other features */ default: + dccp_pr_debug("UNIMPLEMENTED: not handling %s(%d, ...)\n", + dccp_feat_typename(type), feature); rc = -EFAULT; break; } @@ -403,20 +418,27 @@ int dccp_feat_confirm_recv(struct sock *sk, u8 type, u8 feature, u8 t; struct dccp_opt_pend *opt; struct dccp_minisock *dmsk = dccp_msk(sk); - int rc = 1; + int found = 0; int all_confirmed = 1; - dccp_pr_debug("got feat confirm type=%d feat=%d\n", type, feature); - - /* XXX sanity check type & feat */ + dccp_feat_debug(type, feature, *val); /* locate our change request */ - t = type == DCCPO_CONFIRM_L ? DCCPO_CHANGE_R : DCCPO_CHANGE_L; + switch (type) { + case DCCPO_CONFIRM_L: t = DCCPO_CHANGE_R; break; + case DCCPO_CONFIRM_R: t = DCCPO_CHANGE_L; break; + default: pr_info("invalid type %d\n", type); + return 1; + + } + /* XXX sanity check feature value */ list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) { if (!opt->dccpop_conf && opt->dccpop_type == t && opt->dccpop_feat == feature) { - /* we found it */ + found = 1; + dccp_pr_debug("feature %d found\n", opt->dccpop_feat); + /* XXX do sanity check */ opt->dccpop_conf = 1; @@ -425,9 +447,7 @@ int dccp_feat_confirm_recv(struct sock *sk, u8 type, u8 feature, dccp_feat_update(sk, opt->dccpop_type, opt->dccpop_feat, *val); - dccp_pr_debug("feat %d type %d confirmed %d\n", - feature, type, *val); - rc = 0; + /* XXX check the return value of dccp_feat_update */ break; } @@ -446,9 +466,9 @@ int dccp_feat_confirm_recv(struct sock *sk, u8 type, u8 feature, inet_csk_clear_xmit_timer(sk, ICSK_TIME_RETRANS); } - if (rc) - dccp_pr_debug("feat %d type %d never requested\n", - feature, type); + if (!found) + dccp_pr_debug("%s(%d, ...) never requested\n", + dccp_feat_typename(type), feature); return 0; } @@ -583,3 +603,45 @@ out: } EXPORT_SYMBOL_GPL(dccp_feat_init); + +#ifdef CONFIG_IP_DCCP_DEBUG +const char *dccp_feat_typename(const u8 type) +{ + switch(type) { + case DCCPO_CHANGE_L: return("ChangeL"); + case DCCPO_CONFIRM_L: return("ConfirmL"); + case DCCPO_CHANGE_R: return("ChangeR"); + case DCCPO_CONFIRM_R: return("ConfirmR"); + /* the following case must not appear in feature negotation */ + default: dccp_pr_debug("unknown type %d [BUG!]\n", type); + } + return NULL; +} + +EXPORT_SYMBOL_GPL(dccp_feat_typename); + +const char *dccp_feat_name(const u8 feat) +{ + static const char *feature_names[] = { + [DCCPF_RESERVED] = "Reserved", + [DCCPF_CCID] = "CCID", + [DCCPF_SHORT_SEQNOS] = "Allow Short Seqnos", + [DCCPF_SEQUENCE_WINDOW] = "Sequence Window", + [DCCPF_ECN_INCAPABLE] = "ECN Incapable", + [DCCPF_ACK_RATIO] = "Ack Ratio", + [DCCPF_SEND_ACK_VECTOR] = "Send ACK Vector", + [DCCPF_SEND_NDP_COUNT] = "Send NDP Count", + [DCCPF_MIN_CSUM_COVER] = "Min. Csum Coverage", + [DCCPF_DATA_CHECKSUM] = "Send Data Checksum", + }; + if (feat >= DCCPF_MIN_CCID_SPECIFIC) + return "CCID-specific"; + + if (dccp_feat_is_reserved(feat)) + return feature_names[DCCPF_RESERVED]; + + return feature_names[feat]; +} + +EXPORT_SYMBOL_GPL(dccp_feat_name); +#endif /* CONFIG_IP_DCCP_DEBUG */ diff --git a/net/dccp/feat.h b/net/dccp/feat.h index 6048373c71..2c373ad7ed 100644 --- a/net/dccp/feat.h +++ b/net/dccp/feat.h @@ -12,9 +12,46 @@ */ #include +#include "dccp.h" -struct sock; -struct dccp_minisock; +static inline int dccp_feat_is_valid_length(u8 type, u8 feature, u8 len) +{ + /* sec. 6.1: Confirm has at least length 3, + * sec. 6.2: Change has at least length 4 */ + if (len < 3) + return 1; + if (len < 4 && (type == DCCPO_CHANGE_L || type == DCCPO_CHANGE_R)) + return 1; + /* XXX: add per-feature length validation (sec. 6.6.8) */ + return 0; +} + +static inline int dccp_feat_is_reserved(const u8 feat) +{ + return (feat > DCCPF_DATA_CHECKSUM && + feat < DCCPF_MIN_CCID_SPECIFIC) || + feat == DCCPF_RESERVED; +} + +/* feature negotiation knows only these four option types (RFC 4340, sec. 6) */ +static inline int dccp_feat_is_valid_type(const u8 optnum) +{ + return optnum >= DCCPO_CHANGE_L && optnum <= DCCPO_CONFIRM_R; + +} + +#ifdef CONFIG_IP_DCCP_DEBUG +extern const char *dccp_feat_typename(const u8 type); +extern const char *dccp_feat_name(const u8 feat); + +static inline void dccp_feat_debug(const u8 type, const u8 feat, const u8 val) +{ + dccp_pr_debug("%s(%s (%d), %d)\n", dccp_feat_typename(type), + dccp_feat_name(feat), feat, val); +} +#else +#define dccp_feat_debug(type, feat, val) +#endif /* CONFIG_IP_DCCP_DEBUG */ extern int dccp_feat_change(struct dccp_minisock *dmsk, u8 type, u8 feature, u8 *val, u8 len, gfp_t gfp); diff --git a/net/dccp/options.c b/net/dccp/options.c index 121e794fe4..2d0ef27f4a 100644 --- a/net/dccp/options.c +++ b/net/dccp/options.c @@ -465,8 +465,10 @@ static int dccp_insert_feat_opt(struct sk_buff *skb, u8 type, u8 feat, if (len) memcpy(to, val, len); - dccp_pr_debug("option %d feat %d len %d\n", type, feat, len); + dccp_pr_debug("%s(%s (%d), ...), length %d\n", + dccp_feat_typename(type), + dccp_feat_name(feat), feat, len); return 0; }