From 482c119186987110bfccf705a5ac75d399b08766 Mon Sep 17 00:00:00 2001 From: "brian m. carlson" Date: Thu, 11 Feb 2021 02:08:03 +0000 Subject: gpg-interface: improve interface for parsing tags We have a function which parses a buffer with a signature at the end, parse_signature, and this function is used for signed tags. However, we'll need to store values for multiple algorithms, and we'll do this by using a header for the non-default algorithm. Adjust the parse_signature interface to store the parsed data in two strbufs and turn the existing function into parse_signed_buffer. The latter is still used in places where we know we always have a signed buffer, such as push certs. Adjust all the callers to deal with this new interface. Signed-off-by: brian m. carlson Signed-off-by: Junio C Hamano diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c index d49d050..b89ce31 100644 --- a/builtin/receive-pack.c +++ b/builtin/receive-pack.c @@ -764,7 +764,7 @@ static void prepare_push_cert_sha1(struct child_process *proc) memset(&sigcheck, '\0', sizeof(sigcheck)); - bogs = parse_signature(push_cert.buf, push_cert.len); + bogs = parse_signed_buffer(push_cert.buf, push_cert.len); check_signature(push_cert.buf, bogs, push_cert.buf + bogs, push_cert.len - bogs, &sigcheck); @@ -2050,7 +2050,7 @@ static void queue_commands_from_cert(struct command **tail, die("malformed push certificate %.*s", 100, push_cert->buf); else boc += 2; - eoc = push_cert->buf + parse_signature(push_cert->buf, push_cert->len); + eoc = push_cert->buf + parse_signed_buffer(push_cert->buf, push_cert->len); while (boc < eoc) { const char *eol = memchr(boc, '\n', eoc - boc); diff --git a/builtin/tag.c b/builtin/tag.c index ecf0117..7162f4c 100644 --- a/builtin/tag.c +++ b/builtin/tag.c @@ -174,11 +174,17 @@ static void write_tag_body(int fd, const struct object_id *oid) { unsigned long size; enum object_type type; - char *buf, *sp; + char *buf, *sp, *orig; + struct strbuf payload = STRBUF_INIT; + struct strbuf signature = STRBUF_INIT; - buf = read_object_file(oid, &type, &size); + orig = buf = read_object_file(oid, &type, &size); if (!buf) return; + if (parse_signature(buf, size, &payload, &signature)) { + buf = payload.buf; + size = payload.len; + } /* skip header */ sp = strstr(buf, "\n\n"); @@ -187,9 +193,11 @@ static void write_tag_body(int fd, const struct object_id *oid) return; } sp += 2; /* skip the 2 LFs */ - write_or_die(fd, sp, parse_signature(sp, buf + size - sp)); + write_or_die(fd, sp, buf + size - sp); - free(buf); + free(orig); + strbuf_release(&payload); + strbuf_release(&signature); } static int build_tag_object(struct strbuf *buf, int sign, struct object_id *result) diff --git a/commit.c b/commit.c index d2908cb..d9ccbae 100644 --- a/commit.c +++ b/commit.c @@ -1136,8 +1136,10 @@ static void handle_signed_tag(struct commit *parent, struct commit_extra_header struct merge_remote_desc *desc; struct commit_extra_header *mergetag; char *buf; - unsigned long size, len; + unsigned long size; enum object_type type; + struct strbuf payload = STRBUF_INIT; + struct strbuf signature = STRBUF_INIT; desc = merge_remote_util(parent); if (!desc || !desc->obj) @@ -1145,8 +1147,7 @@ static void handle_signed_tag(struct commit *parent, struct commit_extra_header buf = read_object_file(&desc->obj->oid, &type, &size); if (!buf || type != OBJ_TAG) goto free_return; - len = parse_signature(buf, size); - if (size == len) + if (!parse_signature(buf, size, &payload, &signature)) goto free_return; /* * We could verify this signature and either omit the tag when @@ -1165,6 +1166,8 @@ static void handle_signed_tag(struct commit *parent, struct commit_extra_header **tail = mergetag; *tail = &mergetag->next; + strbuf_release(&payload); + strbuf_release(&signature); return; free_return: diff --git a/fmt-merge-msg.c b/fmt-merge-msg.c index 9a664a4..7fd99f0 100644 --- a/fmt-merge-msg.c +++ b/fmt-merge-msg.c @@ -509,22 +509,28 @@ static void fmt_merge_msg_sigs(struct strbuf *out) for (i = 0; i < origins.nr; i++) { struct object_id *oid = origins.items[i].util; enum object_type type; - unsigned long size, len; + unsigned long size; char *buf = read_object_file(oid, &type, &size); + char *origbuf = buf; + unsigned long len = size; struct signature_check sigc = { NULL }; - struct strbuf sig = STRBUF_INIT; + struct strbuf payload = STRBUF_INIT, sig = STRBUF_INIT; if (!buf || type != OBJ_TAG) goto next; - len = parse_signature(buf, size); - if (size == len) - ; /* merely annotated */ - else if (check_signature(buf, len, buf + len, size - len, &sigc) && - !sigc.gpg_output) - strbuf_addstr(&sig, "gpg verification failed.\n"); - else - strbuf_addstr(&sig, sigc.gpg_output); + if (!parse_signature(buf, size, &payload, &sig)) + ;/* merely annotated */ + else { + buf = payload.buf; + len = payload.len; + if (check_signature(payload.buf, payload.len, sig.buf, + sig.len, &sigc) && + !sigc.gpg_output) + strbuf_addstr(&sig, "gpg verification failed.\n"); + else + strbuf_addstr(&sig, sigc.gpg_output); + } signature_check_clear(&sigc); if (!tag_number++) { @@ -547,9 +553,10 @@ static void fmt_merge_msg_sigs(struct strbuf *out) strlen(origins.items[i].string)); fmt_tag_signature(&tagbuf, &sig, buf, len); } + strbuf_release(&payload); strbuf_release(&sig); next: - free(buf); + free(origbuf); } if (tagbuf.len) { strbuf_addch(out, '\n'); diff --git a/gpg-interface.c b/gpg-interface.c index b499270..c6274c1 100644 --- a/gpg-interface.c +++ b/gpg-interface.c @@ -345,7 +345,7 @@ void print_signature_buffer(const struct signature_check *sigc, unsigned flags) fputs(output, stderr); } -size_t parse_signature(const char *buf, size_t size) +size_t parse_signed_buffer(const char *buf, size_t size) { size_t len = 0; size_t match = size; @@ -361,6 +361,17 @@ size_t parse_signature(const char *buf, size_t size) return match; } +int parse_signature(const char *buf, size_t size, struct strbuf *payload, struct strbuf *signature) +{ + size_t match = parse_signed_buffer(buf, size); + if (match != size) { + strbuf_add(payload, buf, match); + strbuf_add(signature, buf + match, size - match); + return 1; + } + return 0; +} + void set_signing_key(const char *key) { free(configured_signing_key); diff --git a/gpg-interface.h b/gpg-interface.h index f4e9b4f..80567e4 100644 --- a/gpg-interface.h +++ b/gpg-interface.h @@ -38,12 +38,19 @@ struct signature_check { void signature_check_clear(struct signature_check *sigc); /* + * Look at a GPG signed tag object. If such a signature exists, store it in + * signature and the signed content in payload. Return 1 if a signature was + * found, and 0 otherwise. + */ +int parse_signature(const char *buf, size_t size, struct strbuf *payload, struct strbuf *signature); + +/* * Look at GPG signed content (e.g. a signed tag object), whose * payload is followed by a detached signature on it. Return the * offset where the embedded detached signature begins, or the end of * the data when there is no such signature. */ -size_t parse_signature(const char *buf, size_t size); +size_t parse_signed_buffer(const char *buf, size_t size); /* * Create a detached signature for the contents of "buffer" and append diff --git a/log-tree.c b/log-tree.c index 7e0335e..b025c8d 100644 --- a/log-tree.c +++ b/log-tree.c @@ -548,7 +548,8 @@ static int show_one_mergetag(struct commit *commit, struct strbuf verify_message; struct signature_check sigc = { 0 }; int status, nth; - size_t payload_size; + struct strbuf payload = STRBUF_INIT; + struct strbuf signature = STRBUF_INIT; hash_object_file(the_hash_algo, extra->value, extra->len, type_name(OBJ_TAG), &oid); @@ -571,13 +572,11 @@ static int show_one_mergetag(struct commit *commit, strbuf_addf(&verify_message, "parent #%d, tagged '%s'\n", nth + 1, tag->tag); - payload_size = parse_signature(extra->value, extra->len); status = -1; - if (extra->len > payload_size) { + if (parse_signature(extra->value, extra->len, &payload, &signature)) { /* could have a good signature */ - status = check_signature(extra->value, payload_size, - extra->value + payload_size, - extra->len - payload_size, &sigc); + status = check_signature(payload.buf, payload.len, + signature.buf, signature.len, &sigc); if (sigc.gpg_output) strbuf_addstr(&verify_message, sigc.gpg_output); else @@ -588,6 +587,8 @@ static int show_one_mergetag(struct commit *commit, show_sig_lines(opt, status, verify_message.buf); strbuf_release(&verify_message); + strbuf_release(&payload); + strbuf_release(&signature); return 0; } diff --git a/ref-filter.c b/ref-filter.c index 606f638..a4c68cf 100644 --- a/ref-filter.c +++ b/ref-filter.c @@ -1215,7 +1215,13 @@ static void find_subpos(const char *buf, size_t *nonsiglen, const char **sig, size_t *siglen) { + struct strbuf payload = STRBUF_INIT; + struct strbuf signature = STRBUF_INIT; const char *eol; + const char *end = buf + strlen(buf); + const char *sigstart; + + /* skip past header until we hit empty line */ while (*buf && *buf != '\n') { eol = strchrnul(buf, '\n'); @@ -1228,14 +1234,15 @@ static void find_subpos(const char *buf, buf++; /* parse signature first; we might not even have a subject line */ - *sig = buf + parse_signature(buf, strlen(buf)); - *siglen = strlen(*sig); + parse_signature(buf, end - buf, &payload, &signature); + *sig = strbuf_detach(&signature, siglen); + sigstart = buf + parse_signed_buffer(buf, strlen(buf)); /* subject is first non-empty line */ *sub = buf; /* subject goes to first empty line before signature begins */ if ((eol = strstr(*sub, "\n\n"))) { - eol = eol < *sig ? eol : *sig; + eol = eol < sigstart ? eol : sigstart; /* check if message uses CRLF */ } else if (! (eol = strstr(*sub, "\r\n\r\n"))) { /* treat whole message as subject */ @@ -1253,7 +1260,7 @@ static void find_subpos(const char *buf, buf++; *body = buf; *bodylen = strlen(buf); - *nonsiglen = *sig - buf; + *nonsiglen = sigstart - buf; } /* @@ -1291,6 +1298,7 @@ static void grab_sub_body_contents(struct atom_value *val, int deref, void *buf) struct used_atom *atom = &used_atom[i]; const char *name = atom->name; struct atom_value *v = &val[i]; + if (!!deref != (*name == '*')) continue; if (deref) @@ -1336,7 +1344,9 @@ static void grab_sub_body_contents(struct atom_value *val, int deref, void *buf) v->s = strbuf_detach(&s, NULL); } else if (atom->u.contents.option == C_BARE) v->s = xstrdup(subpos); + } + free((void *)sigpos); } /* diff --git a/tag.c b/tag.c index 1ed2684..3e18a41 100644 --- a/tag.c +++ b/tag.c @@ -13,26 +13,27 @@ const char *tag_type = "tag"; static int run_gpg_verify(const char *buf, unsigned long size, unsigned flags) { struct signature_check sigc; - size_t payload_size; + struct strbuf payload = STRBUF_INIT; + struct strbuf signature = STRBUF_INIT; int ret; memset(&sigc, 0, sizeof(sigc)); - payload_size = parse_signature(buf, size); - - if (size == payload_size) { + if (!parse_signature(buf, size, &payload, &signature)) { if (flags & GPG_VERIFY_VERBOSE) - write_in_full(1, buf, payload_size); + write_in_full(1, buf, size); return error("no signature found"); } - ret = check_signature(buf, payload_size, buf + payload_size, - size - payload_size, &sigc); + ret = check_signature(payload.buf, payload.len, signature.buf, + signature.len, &sigc); if (!(flags & GPG_VERIFY_OMIT_STATUS)) print_signature_buffer(&sigc, flags); signature_check_clear(&sigc); + strbuf_release(&payload); + strbuf_release(&signature); return ret; } -- cgit v0.10.2-6-g49f6