This patch makes git-imap-send CRAM-MD5 authenticate method ready. In theory, CRAM-MD5 authenticate method doesn't depend on SSL. But for easiness of maintainance, this patch uses base64 and md5 stuffs of OpenSSL. So if you want to use CRAM-MD5 authenticate method, you have to build git-imap-send with OpenSSL library. Cc: Erik Faye-Lund <kusmabite@xxxxxxxxxxxxxx> Cc: Jakub Narebski <jnareb@xxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Jeff King <peff@xxxxxxxx> Signed-off-by: Hitoshi Mitake <mitake@xxxxxxxxxxxxxxxxxxxxx> --- v3: Erik noticed that there were some garbage lines in this patch. I removed these. And 2/2 wasn't changed, I'm sending 1/2 only. v4: Based on Junio's indication, I cleaned up some points of imap-send.c . v5: Based on Erik's advice, cram() now uses die() if git-imap-send is built with NO_OPENSSL. And based on Junio's indication, some error checking code are added. Documentation/git-imap-send.txt | 4 + imap-send.c | 154 +++++++++++++++++++++++++++++++++++---- 2 files changed, 143 insertions(+), 15 deletions(-) diff --git a/Documentation/git-imap-send.txt b/Documentation/git-imap-send.txt index 57db955..6cafbe2 100644 --- a/Documentation/git-imap-send.txt +++ b/Documentation/git-imap-send.txt @@ -71,6 +71,10 @@ imap.preformattedHTML:: option causes Thunderbird to send the patch as a plain/text, format=fixed email. Default is `false`. +imap.authMethod:: + Specify authenticate method for authentication with IMAP server. + Current supported method is 'CRAM-MD5' only. + Examples ~~~~~~~~ diff --git a/imap-send.c b/imap-send.c index ba72fa4..20f18b2 100644 --- a/imap-send.c +++ b/imap-send.c @@ -25,8 +25,12 @@ #include "cache.h" #include "exec_cmd.h" #include "run-command.h" + #ifdef NO_OPENSSL typedef void *SSL; +#else +#include <openssl/evp.h> +#include <openssl/hmac.h> #endif struct store_conf { @@ -140,6 +144,20 @@ struct imap_server_conf { int use_ssl; int ssl_verify; int use_html; + char *auth_method; +}; + +static struct imap_server_conf server = { + NULL, /* name */ + NULL, /* tunnel */ + NULL, /* host */ + 0, /* port */ + NULL, /* user */ + NULL, /* pass */ + 0, /* use_ssl */ + 1, /* ssl_verify */ + 0, /* use_html */ + NULL, /* auth_method */ }; struct imap_store_conf { @@ -214,6 +232,7 @@ enum CAPABILITY { LITERALPLUS, NAMESPACE, STARTTLS, + AUTH_CRAM_MD5, }; static const char *cap_list[] = { @@ -222,6 +241,7 @@ static const char *cap_list[] = { "LITERAL+", "NAMESPACE", "STARTTLS", + "AUTH=CRAM-MD5", }; #define RESP_OK 0 @@ -949,6 +969,94 @@ static void imap_close_store(struct store *ctx) free(ctx); } +#ifndef NO_OPENSSL + +/* + * hexchar() and cram() functions are + * based on ones of isync project ... http://isync.sf.net/ + * Thanks! + */ +static char hexchar(unsigned int b) +{ + return b < 10 ? '0' + b : 'a' + (b - 10); +} + +#define ENCODED_SIZE(n) (4 * ((n + 2) / 3)) +static char *cram(const char *challenge_64, const char *user, const char *pass) +{ + int i, ret, resp_len; + HMAC_CTX hmac; + unsigned char hash[16]; + char hex[33]; + char *challenge, *response; + char *response_64; + + /* + * challenge must be shorter than challenge_64 + * because we are decoding base64 + */ + challenge = xcalloc(strlen(challenge_64) + 1, sizeof(char)); + ret = EVP_DecodeBlock((unsigned char *)challenge, + (unsigned char *)challenge_64, strlen(challenge_64)); + if (ret != strlen(challenge) + 1) { + free(challenge); + return NULL; + } + HMAC_Init(&hmac, (unsigned char *)pass, strlen(pass), EVP_md5()); + HMAC_Update(&hmac, (unsigned char *)challenge, strlen(challenge)); + HMAC_Final(&hmac, hash, NULL); + HMAC_CTX_cleanup(&hmac); + free(challenge); + + hex[32] = 0; + for (i = 0; i < 16; i++) { + hex[2 * i] = hexchar((hash[i] >> 4) & 0xf); + hex[2 * i + 1] = hexchar(hash[i] & 0xf); + } + + /* length: "<user> <digest in hex>" */ + resp_len = strlen(user) + 1 + strlen(hex) + 1; + response = xcalloc(resp_len, sizeof(char)); + snprintf(response, resp_len, "%s %s", user, hex); + + response_64 = xcalloc(ENCODED_SIZE(resp_len), sizeof(char)); + ret = EVP_EncodeBlock((unsigned char *)response_64, + (unsigned char *)response, strlen(response)); + if (ret != strlen(response_64)) { + free(response_64); + return NULL; + } + return response_64; +} + +#else + +static char *cram(const char *challenge_64, const char *user, const char *pass) +{ + die("If you want to use CRAM-MD5 authenticate method," + "you have to build git-imap-send with OpenSSL library\n"); +} + +#endif + +static int auth_cram_md5(struct imap_store *ctx, struct imap_cmd *cmd, const char *prompt) +{ + int ret; + char *response; + + response = cram(prompt, server.user, server.pass); + if (!response) + return error("IMAP error: generating response failed\n"); + + ret = socket_write(&ctx->imap->buf.sock, response, strlen(response)); + if (ret != strlen(response)) + return error("IMAP error: sending response failed\n"); + + free(response); + + return 0; +} + static struct store *imap_open_store(struct imap_server_conf *srvc) { struct imap_store *ctx; @@ -1130,9 +1238,34 @@ static struct store *imap_open_store(struct imap_server_conf *srvc) if (!imap->buf.sock.ssl) imap_warn("*** IMAP Warning *** Password is being " "sent in the clear\n"); - if (imap_exec(ctx, NULL, "LOGIN \"%s\" \"%s\"", srvc->user, srvc->pass) != RESP_OK) { - fprintf(stderr, "IMAP error: LOGIN failed\n"); - goto bail; + + if (srvc->auth_method) { + struct imap_cmd_cb cb; + + if (!strcmp(srvc->auth_method, "CRAM-MD5")) { + if (!CAP(AUTH_CRAM_MD5)) { + fprintf(stderr, "You specified" + "CRAM-MD5 as authentication method, " + "but %s doesn't support it.\n", srvc->host); + goto bail; + } + /* CRAM-MD5 */ + + memset(&cb, 0, sizeof(cb)); + cb.cont = auth_cram_md5; + if (imap_exec(ctx, &cb, "AUTHENTICATE CRAM-MD5") != RESP_OK) { + fprintf(stderr, "IMAP error: AUTHENTICATE CRAM-MD5 failed\n"); + goto bail; + } + } else { + fprintf(stderr, "Unknown authentication method:%s\n", srvc->host); + goto bail; + } + } else { + if (imap_exec(ctx, NULL, "LOGIN \"%s\" \"%s\"", srvc->user, srvc->pass) != RESP_OK) { + fprintf(stderr, "IMAP error: LOGIN failed\n"); + goto bail; + } } } /* !preauth */ @@ -1310,18 +1443,6 @@ static int split_msg(struct msg_data *all_msgs, struct msg_data *msg, int *ofs) return 1; } -static struct imap_server_conf server = { - NULL, /* name */ - NULL, /* tunnel */ - NULL, /* host */ - 0, /* port */ - NULL, /* user */ - NULL, /* pass */ - 0, /* use_ssl */ - 1, /* ssl_verify */ - 0, /* use_html */ -}; - static char *imap_folder; static int git_imap_config(const char *key, const char *val, void *cb) @@ -1361,6 +1482,9 @@ static int git_imap_config(const char *key, const char *val, void *cb) server.port = git_config_int(key, val); else if (!strcmp("tunnel", key)) server.tunnel = xstrdup(val); + else if (!strcmp("authmethod", key)) + server.auth_method = xstrdup(val); + return 0; } -- 1.7.0.rc1.52.gf7cc2.dirty -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html