Merge branch 'js/test-git-installed'
[gitweb.git] / gpg-interface.c
index 0647bd6348cdedd0e32f30ed23934d390eae4122..8ed274533f87198a74a3660809c25932fa43124a 100644 (file)
@@ -7,10 +7,64 @@
 #include "tempfile.h"
 
 static char *configured_signing_key;
-static const char *gpg_program = "gpg";
+struct gpg_format {
+       const char *name;
+       const char *program;
+       const char **verify_args;
+       const char **sigs;
+};
+
+static const char *openpgp_verify_args[] = {
+       "--keyid-format=long",
+       NULL
+};
+static const char *openpgp_sigs[] = {
+       "-----BEGIN PGP SIGNATURE-----",
+       "-----BEGIN PGP MESSAGE-----",
+       NULL
+};
+
+static const char *x509_verify_args[] = {
+       NULL
+};
+static const char *x509_sigs[] = {
+       "-----BEGIN SIGNED MESSAGE-----",
+       NULL
+};
 
-#define PGP_SIGNATURE "-----BEGIN PGP SIGNATURE-----"
-#define PGP_MESSAGE "-----BEGIN PGP MESSAGE-----"
+static struct gpg_format gpg_format[] = {
+       { .name = "openpgp", .program = "gpg",
+         .verify_args = openpgp_verify_args,
+         .sigs = openpgp_sigs
+       },
+       { .name = "x509", .program = "gpgsm",
+         .verify_args = x509_verify_args,
+         .sigs = x509_sigs
+       },
+};
+
+static struct gpg_format *use_format = &gpg_format[0];
+
+static struct gpg_format *get_format_by_name(const char *str)
+{
+       int i;
+
+       for (i = 0; i < ARRAY_SIZE(gpg_format); i++)
+               if (!strcmp(gpg_format[i].name, str))
+                       return gpg_format + i;
+       return NULL;
+}
+
+static struct gpg_format *get_format_by_sig(const char *sig)
+{
+       int i, j;
+
+       for (i = 0; i < ARRAY_SIZE(gpg_format); i++)
+               for (j = 0; gpg_format[i].sigs[j]; j++)
+                       if (starts_with(sig, gpg_format[i].sigs[j]))
+                               return gpg_format + i;
+       return NULL;
+}
 
 void signature_check_clear(struct signature_check *sigc)
 {
@@ -19,49 +73,115 @@ void signature_check_clear(struct signature_check *sigc)
        FREE_AND_NULL(sigc->gpg_status);
        FREE_AND_NULL(sigc->signer);
        FREE_AND_NULL(sigc->key);
+       FREE_AND_NULL(sigc->fingerprint);
+       FREE_AND_NULL(sigc->primary_key_fingerprint);
 }
 
+/* An exclusive status -- only one of them can appear in output */
+#define GPG_STATUS_EXCLUSIVE   (1<<0)
+/* The status includes key identifier */
+#define GPG_STATUS_KEYID       (1<<1)
+/* The status includes user identifier */
+#define GPG_STATUS_UID         (1<<2)
+/* The status includes key fingerprints */
+#define GPG_STATUS_FINGERPRINT (1<<3)
+
+/* Short-hand for standard exclusive *SIG status with keyid & UID */
+#define GPG_STATUS_STDSIG      (GPG_STATUS_EXCLUSIVE|GPG_STATUS_KEYID|GPG_STATUS_UID)
+
 static struct {
        char result;
        const char *check;
+       unsigned int flags;
 } sigcheck_gpg_status[] = {
-       { 'G', "\n[GNUPG:] GOODSIG " },
-       { 'B', "\n[GNUPG:] BADSIG " },
-       { 'U', "\n[GNUPG:] TRUST_NEVER" },
-       { 'U', "\n[GNUPG:] TRUST_UNDEFINED" },
-       { 'E', "\n[GNUPG:] ERRSIG "},
-       { 'X', "\n[GNUPG:] EXPSIG "},
-       { 'Y', "\n[GNUPG:] EXPKEYSIG "},
-       { 'R', "\n[GNUPG:] REVKEYSIG "},
+       { 'G', "GOODSIG ", GPG_STATUS_STDSIG },
+       { 'B', "BADSIG ", GPG_STATUS_STDSIG },
+       { 'U', "TRUST_NEVER", 0 },
+       { 'U', "TRUST_UNDEFINED", 0 },
+       { 'E', "ERRSIG ", GPG_STATUS_EXCLUSIVE|GPG_STATUS_KEYID },
+       { 'X', "EXPSIG ", GPG_STATUS_STDSIG },
+       { 'Y', "EXPKEYSIG ", GPG_STATUS_STDSIG },
+       { 'R', "REVKEYSIG ", GPG_STATUS_STDSIG },
+       { 0, "VALIDSIG ", GPG_STATUS_FINGERPRINT },
 };
 
-void parse_gpg_output(struct signature_check *sigc)
+static void parse_gpg_output(struct signature_check *sigc)
 {
        const char *buf = sigc->gpg_status;
-       int i;
-
-       /* Iterate over all search strings */
-       for (i = 0; i < ARRAY_SIZE(sigcheck_gpg_status); i++) {
-               const char *found, *next;
-
-               if (!skip_prefix(buf, sigcheck_gpg_status[i].check + 1, &found)) {
-                       found = strstr(buf, sigcheck_gpg_status[i].check);
-                       if (!found)
-                               continue;
-                       found += strlen(sigcheck_gpg_status[i].check);
-               }
-               sigc->result = sigcheck_gpg_status[i].result;
-               /* The trust messages are not followed by key/signer information */
-               if (sigc->result != 'U') {
-                       sigc->key = xmemdupz(found, 16);
-                       /* The ERRSIG message is not followed by signer information */
-                       if (sigc-> result != 'E') {
-                               found += 17;
-                               next = strchrnul(found, '\n');
-                               sigc->signer = xmemdupz(found, next - found);
+       const char *line, *next;
+       int i, j;
+       int seen_exclusive_status = 0;
+
+       /* Iterate over all lines */
+       for (line = buf; *line; line = strchrnul(line+1, '\n')) {
+               while (*line == '\n')
+                       line++;
+               /* Skip lines that don't start with GNUPG status */
+               if (!skip_prefix(line, "[GNUPG:] ", &line))
+                       continue;
+
+               /* Iterate over all search strings */
+               for (i = 0; i < ARRAY_SIZE(sigcheck_gpg_status); i++) {
+                       if (skip_prefix(line, sigcheck_gpg_status[i].check, &line)) {
+                               if (sigcheck_gpg_status[i].flags & GPG_STATUS_EXCLUSIVE) {
+                                       if (seen_exclusive_status++)
+                                               goto found_duplicate_status;
+                               }
+
+                               if (sigcheck_gpg_status[i].result)
+                                       sigc->result = sigcheck_gpg_status[i].result;
+                               /* Do we have key information? */
+                               if (sigcheck_gpg_status[i].flags & GPG_STATUS_KEYID) {
+                                       next = strchrnul(line, ' ');
+                                       free(sigc->key);
+                                       sigc->key = xmemdupz(line, next - line);
+                                       /* Do we have signer information? */
+                                       if (*next && (sigcheck_gpg_status[i].flags & GPG_STATUS_UID)) {
+                                               line = next + 1;
+                                               next = strchrnul(line, '\n');
+                                               free(sigc->signer);
+                                               sigc->signer = xmemdupz(line, next - line);
+                                       }
+                               }
+                               /* Do we have fingerprint? */
+                               if (sigcheck_gpg_status[i].flags & GPG_STATUS_FINGERPRINT) {
+                                       next = strchrnul(line, ' ');
+                                       free(sigc->fingerprint);
+                                       sigc->fingerprint = xmemdupz(line, next - line);
+
+                                       /* Skip interim fields */
+                                       for (j = 9; j > 0; j--) {
+                                               if (!*next)
+                                                       break;
+                                               line = next + 1;
+                                               next = strchrnul(line, ' ');
+                                       }
+
+                                       next = strchrnul(line, '\n');
+                                       free(sigc->primary_key_fingerprint);
+                                       sigc->primary_key_fingerprint = xmemdupz(line, next - line);
+                               }
+
+                               break;
                        }
                }
        }
+       return;
+
+found_duplicate_status:
+       /*
+        * GOODSIG, BADSIG etc. can occur only once for each signature.
+        * Therefore, if we had more than one then we're dealing with multiple
+        * signatures.  We don't support them currently, and they're rather
+        * hard to create, so something is likely fishy and we should reject
+        * them altogether.
+        */
+       sigc->result = 'E';
+       /* Clear partial data to avoid confusion */
+       FREE_AND_NULL(sigc->primary_key_fingerprint);
+       FREE_AND_NULL(sigc->fingerprint);
+       FREE_AND_NULL(sigc->signer);
+       FREE_AND_NULL(sigc->key);
 }
 
 int check_signature(const char *payload, size_t plen, const char *signature,
@@ -81,12 +201,13 @@ int check_signature(const char *payload, size_t plen, const char *signature,
        sigc->gpg_output = strbuf_detach(&gpg_output, NULL);
        sigc->gpg_status = strbuf_detach(&gpg_status, NULL);
        parse_gpg_output(sigc);
+       status |= sigc->result != 'G' && sigc->result != 'U';
 
  out:
        strbuf_release(&gpg_status);
        strbuf_release(&gpg_output);
 
-       return sigc->result != 'G' && sigc->result != 'U';
+       return !!status;
 }
 
 void print_signature_buffer(const struct signature_check *sigc, unsigned flags)
@@ -101,12 +222,6 @@ void print_signature_buffer(const struct signature_check *sigc, unsigned flags)
                fputs(output, stderr);
 }
 
-static int is_gpg_start(const char *line)
-{
-       return starts_with(line, PGP_SIGNATURE) ||
-               starts_with(line, PGP_MESSAGE);
-}
-
 size_t parse_signature(const char *buf, size_t size)
 {
        size_t len = 0;
@@ -114,7 +229,7 @@ size_t parse_signature(const char *buf, size_t size)
        while (len < size) {
                const char *eol;
 
-               if (is_gpg_start(buf + len))
+               if (get_format_by_sig(buf + len))
                        match = len;
 
                eol = memchr(buf + len, '\n', size - len);
@@ -131,6 +246,9 @@ void set_signing_key(const char *key)
 
 int git_gpg_config(const char *var, const char *value, void *cb)
 {
+       struct gpg_format *fmt = NULL;
+       char *fmtname = NULL;
+
        if (!strcmp(var, "user.signingkey")) {
                if (!value)
                        return config_error_nonbool(var);
@@ -138,13 +256,28 @@ int git_gpg_config(const char *var, const char *value, void *cb)
                return 0;
        }
 
-       if (!strcmp(var, "gpg.program")) {
+       if (!strcmp(var, "gpg.format")) {
                if (!value)
                        return config_error_nonbool(var);
-               gpg_program = xstrdup(value);
+               fmt = get_format_by_name(value);
+               if (!fmt)
+                       return error("unsupported value for %s: %s",
+                                    var, value);
+               use_format = fmt;
                return 0;
        }
 
+       if (!strcmp(var, "gpg.program") || !strcmp(var, "gpg.openpgp.program"))
+               fmtname = "openpgp";
+
+       if (!strcmp(var, "gpg.x509.program"))
+               fmtname = "x509";
+
+       if (fmtname) {
+               fmt = get_format_by_name(fmtname);
+               return git_config_string(&fmt->program, var, value);
+       }
+
        return 0;
 }
 
@@ -163,7 +296,7 @@ int sign_buffer(struct strbuf *buffer, struct strbuf *signature, const char *sig
        struct strbuf gpg_status = STRBUF_INIT;
 
        argv_array_pushl(&gpg.args,
-                        gpg_program,
+                        use_format->program,
                         "--status-fd=2",
                         "-bsau", signing_key,
                         NULL);
@@ -201,6 +334,7 @@ int verify_signed_buffer(const char *payload, size_t payload_size,
                         struct strbuf *gpg_output, struct strbuf *gpg_status)
 {
        struct child_process gpg = CHILD_PROCESS_INIT;
+       struct gpg_format *fmt;
        struct tempfile *temp;
        int ret;
        struct strbuf buf = STRBUF_INIT;
@@ -216,10 +350,14 @@ int verify_signed_buffer(const char *payload, size_t payload_size,
                return -1;
        }
 
+       fmt = get_format_by_sig(signature);
+       if (!fmt)
+               BUG("bad signature '%s'", signature);
+
+       argv_array_push(&gpg.args, fmt->program);
+       argv_array_pushv(&gpg.args, fmt->verify_args);
        argv_array_pushl(&gpg.args,
-                        gpg_program,
                         "--status-fd=1",
-                        "--keyid-format=long",
                         "--verify", temp->filename.buf, "-",
                         NULL);